Impact of war and geopolitics on health in Palestine Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Life under occupation: the health and well-being of Palestinians Last updated: 08/01/26, 18:56 Published: 13/03/25, 08:00 Impact of war and geopolitics on health in Palestine This is article no. 1 in a series about global health injustices. Next article: Civil war in Sudan . Introduction Welcome to the Global Health Injustices Series, which will focus on critically examining the health inequalities and inequities faced by vulnerable populations within different countries and regions worldwide and even put forward actionable steps to improve their health and wellbeing. This series will begin with Palestine, as it has been an enduring crisis that should be addressed to include long-lasting benefits and outcomes for the Palestinians. Palestine: from a rich history to current occupation Palestine is a country in the Middle East (West Asia) mainly bordered by Israel. Palestine is unique in its various cultures and knowledge, moulded by multifaceted events and geopolitical shifts over centuries. The multidimensional cultural landscape of Palestine illustrates the impact of civilisations, such as the Romans, Byzantines, and Ottomans, who each had their religions, languages, and cultures, which still exist in various forms today. The resilience of the Palestinians is evident through their distinct traditions, art, food and environment, which are essential to their identity. With these testaments in mind, Palestinians are facing consistent strife because they are under constant occupation, blockade and cutting off of needed supplies carried out by Israel, as noted by several humanitarian and human rights non-governmental organisations (NGOs) like Amnesty International and Save the Children. These actions are facilitated by nations, notably the United States and the United Kingdom, through arms and weapons trade. Hence, the struggle for the Palestinians to have autonomy and freedom, among other human rights within their own homeland, is a consistent fight that requires ongoing international cooperation and solidarity. Geopolitics: its detrimental impacts on the Palestinians Given the currently divisive geopolitical landscape, it is essential to bring attention to the health outcomes of the Palestinian population, especially since at least half of them are children. A report from the Global Nutrition Cluster called “Nutrition Vulnerability and Situation Analysis / Gaza” had several key findings and tables (see Tables 1 and 2 ). Firstly, more than 90% of children less than a year old, along with pregnant and breastfeeding women, encounter high under-nutrition due to poverty. Another finding was that approximately 90% of children under five are impacted by at least one infectious disease, and 81% of households in Gaza lack clean and safe water. However, the authors noted limitations in their analysis, such as limited data sources because collecting it is difficult within the context of Gaza, and this was true for screening. Another report from the organisation Medical Aid For Palestinians (MAP), titled “Health Under Occupation” from 2017, discussed healthcare access and outcomes more broadly. For example, they noted that in 2016, up to one-third of patients’ permits to exit Gaza for healthcare access were either denied or delayed. Moreover, they stated that 40% of people in Gaza live below the poverty line. Given the recent geopolitical shifts in power, these findings from both reports will likely be higher now. This brings forthcoming uncertainty about whether the health outcomes of Palestinians will improve. In a recent qualitative study involving the views of Palestinian physicians in the West Bank, they shared their experiences of violence, threats of violence, issues with healthcare access for themselves and patients, financial difficulties to support their families, struggle to help their patients and limited access to education due to harsher life under occupation. Thinking more largely about emergency care in Palestine, one scoping review reported the depletion of healthcare resources such as medical equipment and medications. The authors even related how human rights violations and the destruction of the Palestinian healthcare system, including emergencies, have exacerbated outcomes; the most notable were stroke, myocardial infarction and traumatic injury, among other non-infectious diseases. Although the authors included this information from a human rights standpoint, they called for additional interventions and research to fill in and learn gaps within emergency care to enhance health outcomes for Palestinians. This review was published in 2022, and again, many geopolitical shifts in power have taken place within a few years. Therefore, it can be deduced that emergency care is drastically needed for the Palestinians; this is primarily compelled by the blockade in Gaza and occupation in the West Bank. Focusing on the mental health outcomes among Palestinians, they have become worse. In another scoping review, researchers focused on trauma among young Palestinian people in Gaza; the authors noted that events, such as exposure to devastation and violence, as well as the death or loss of friends and family, have contributed to mental health outcomes ranging from post-traumatic stress disorder (PTSD) to depression. Nevertheless, the authors stated that further qualitative research is vital to addressing gaps in knowledge and enhancing mental health outcomes among the Palestinian youth and the wider population. Connecting back to how the modern geopolitical landscape is very dynamic, the poorer mental health outcomes among Palestinians have conceivably increased. Urgent calls to action: recommendations from NGOs to upholding human rights Given all of these detrimental impacts on the health and wellbeing of Palestinians, there are recommendations from organisations, notably the United Nations (UN), for ways forward towards upholding the human rights of Palestinians: Immediately end all practices of collective punishment, including lifting its blockade and closures – and the “complete siege”- of Gaza, and urgently ensure immediate access to humanitarian and commercial goods throughout Gaza, commensurate with the immense humanitarian needs. Ensure that all Palestinians forcibly displaced from Gaza are allowed to return to their homes creating safe conditions and fulfil its responsibilities as an occupying Power in this regard. End the 56-year occupation of the Occupied Palestinian Territory, including East Jerusalem as part of a broader process towards achieving equality, justice, democracy, non-discrimination, and the fulfilment of all human rights for all Palestinians. These recommendations, among others mentioned in the report from the United Nations (UN) High Commissioner for Human Rights, were divulged in 2024; the year had been a challenging time, particularly in Gaza, due to the complete blockade of food, water and essentials like medical supplies; in addition to this, many explosives were dropped on Gaza, killing thousands of men, women and children. Finally, buildings, such as hospitals and homes, were destroyed. Conclusion: moving forward towards a equitable and equal future for Palestinians Reflecting on everything discussed in this article, the numerous injustices happening to Palestinians must not go on; they have been suppressed for nearly 75 years by governments and the mainstream media before receiving closer attention, examination and debate within Western society recently. Therefore, we need to take actionable steps by initiating more open discussions of justice and advocacy involving the voices of Palestinians, such as myself and others. Furthermore, it is crucial always to nudge those in positions of power worldwide to fulfil their responsibilities as civil servants and defend human rights for everyone. Both of these actions uphold the health and wellbeing of Palestinians living in Gaza and the West Bank, especially as enabling the recommendations from the UN and other NGOs. As for the wider international community, we must continue upholding human rights to maintain our health and wellbeing. In my next article, I will discuss Sudan because this population has also encountered many injustices, primarily the civil war that has been occurring since 2023. This has impacted the health and wellbeing of the Sudanese population, which requires thorough attention and discussion. Written by Sam Jarada Related articles: Gentrification and well-being / Health Inequalities / Impacts of global warming on NTDs / Global health injustices- Bangladesh , Sri Lankan Tamils REFERENCES Human rights in Israel and the Occupied Palestinian Territory. Amnesty International. 2022. Available from: https://www.amnesty.org/en/location/middle-east-and-north-africa/middle-east/israel-and-the-occupied-palestinian-territory/report-israel-and-the-occupied-palestinian-territory/ Occupied Palestinian Territory. Save the Children International. 2024. Available from: https://www.savethechildren.net/occupied-palestinian-territory Nutrition Vulnerability and Situation Analysis / Gaza. 2024. Available from: https://www.nutritioncluster.net/sites/nutritioncluster.com/files/2024-02/GAZA-Nutrition-vulnerability-and-SitAn-v7.pdf HEALTH UNDER OCCUPATION. Medical Aid For Palestinians. 2017. Available from: https://www.map.org.uk/downloads/health-under-occupation---map-report-2017.pdf Husam Dweik, Hadwan AA, Beesan Maraqa, Taher A, Zink T. Perspectives of Palestinian physicians on the impact of the Gaza War in the West Bank. SSM - Qualitative Research in Health. 2024 Nov 14;6:100504–4. Available from: https://www.sciencedirect.com/science/article/pii/S2667321524001136 Rosenbloom R, Leff R. Emergency Care in the Occupied Palestinian Territory: A Scoping Review. Health and Human Rights. 2022 Dec;24(2):255. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC9790939/ Abdallah Abudayya, Fugleberg T, Nyhus HB, Radwan Aburukba, Tofthagen R. Consequences of war-related traumatic stress among Palestinian young people in the Gaza Strip: A scoping review. Mental Health & Prevention. 2023 Nov 25;32:200305–5. Available from: https://www.sciencedirect.com/science/article/pii/S2212657023000478 M.I. Human rights situation in the Occupied Palestinian Territory, including East Jerusalem, and the obligation to ensure accountability and justice - Report of the United Nations High Commissioner for Human Rights - Advance unedited version (A/HRC/55/28) - Question of Palestine. United Nations. Available from: https://www.un.org/unispal/document/human-rights-situation-in-opt-unohchr-23feb-2024/ Project Gallery

Dysregulation of this pathway occurs in many different types of cancers Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link The MAPK/ERK signalling pathway in cancer Last updated: 24/02/25, 11:29 Published: 20/02/25, 08:00 Dysregulation of this pathway occurs in many different types of cancers Introduction The mitogen-activated protein kinase (MAPK) signalling pathway is an important pathway in apoptosis, proliferation, differentiation, angiogenesis and metastasis. It is a protein kinase pathway (causes phosphorylation) with between 3-5 sets of kinases and is known to be activated via Ras, KC-mediated (Kupffer cells/liver macrophages), Ca2+, or G protein-coupled receptors. The MAPK/ERK pathway, also known as the Ras-Raf-MEK-ERK pathway, is conserved in mammals, and dysregulation of this pathway occurs in many different types of cancers. MAPK/ERK function Ras (GTPase) activates Raf (serine/threonine kinase), which activates MEK1/2 (tyrosine & serine/threonine kinases) and ERK1/2 (serine/threonine kinases), which controls certain transcription factors. ERK1/2 also phosphorylates various substrates in the cytoplasm (not shown). This results in gene expression, which can cause apoptosis, cell cycle regulation, differentiation, proliferation, etc. (Fig. 1). It is estimated that there are more than 150 target substrates of ERK1/2, either directly or indirectly. Furthermore, Ras and RAF have several different subtypes which have different functions. Ras has four different subtypes, which are the GTPases: HRAS, KRAS4A/4B, and NRAS, with KRAS being the common form found in human cancers. RAF has subtypes, which are the kinases: ARAF, BRAF, and CRAF (in humans). Ras is activated when GRB2 (growth-factor-receptor bound protein 2) binds to SOS (son of sevenless). This occurs via the complex moving to the cell membrane upon activation of a transmembrane receptor, such as EGFR (epidermal growth factor receptor). SOS transports the signal from the receptor to RAS and aids in the conversion of RAS-GDP to RAS-GTP. This switches ‘on’ RAF, which leads to the phosphorylation of MEK and ERK (Fig. 1). ERK is then able to move into the nucleus and alter gene expression, of genes such as CREB, MYC, FOS, MSK, ELK, JUN, etc., which are involved in processes such as metabolism, proliferation, angiogenesis (formation of blood vessels), haematopoiesis (formation of blood cells), wound healing, differentiation, inflammation, and cancer. However, ERK is also able to activate other substrates in the cytoplasm, such as BIM, RSK, MNK, and MCL, which are involved in processes such as apoptosis and blood pressure regulation. A regular level of ERK expression is needed for activation of genes involved in the cell cycle and to inhibit negative cell cycle control. ERK phosphorylates Cyclin D and Cdk4/6, which are bound together and aid the cell in the movement from G1 (gap) to the S phase (DNA synthesis/repair) of the cell cycle. MAPK/ERK pathway in cancer The MAPK/ERK pathway has been linked with many cancers, such as colon, thyroid, melanoma, pancreatic, lung, and glioblastoma. Mutations in epidermal growth factor receptor (EGFR), Ras, and Raf are well-known to cause cancer, with an estimated 33% of cancers containing Ras mutations, and an estimated 8% being caused by Raf mutations. It is also estimated that 85% of cancers have elevated activity of MEK. The MAPK/ERK pathway has also been shown to interact with the PI3K/Akt pathway, which controls the cell cycle and causes increased cell proliferation, which is obviously an important factor in tumourigenesis (tumour initiation). Regulation of the MAPK/ERK pathway There is a negative feedback mechanism of ERK1/2 on RAS/RAF/MEK, by ERK1/2 phosphorylating SOS, which causes the RAF-RAS link to be disrupted. ERK also inhibits MEK via the phosphorylation of BRAF and CRAF. There are inhibitors for Ras/Raf/MEK/ERK, but not all of these inhibitors work well/are without issues. ERK is problematic, in that their ATP-binding sites are very like cell cycle proteins, so are more difficult to inhibit. Also, it is difficult to target Ras due to its high GTP binding affinity, profuse cellular GTP, and lack of appropriate binding pockets. Therefore, the main focus currently appears to be on Raf/MEK inhibition. Raf inhibitors include drugs such as sorafenib, vemurafenib, encorafenib, and dabrafenib (these drugs are used on specific BRAF mutations). On the other hand, MEK inhibitors include drugs such as trametinib, cobimetinib, binimetinib, and selumetinib (these drugs can be used on specific mutations in Ras and Ras/Raf). Negative feedback mechanisms tightly control the MEK/ERK pathway and therefore great care is taken with inhibitor drug doses. To illustrate, if the doses are too low, the negative feedback loops are activated, which can lead to drug resistance/ poor therapeutic outcome. Conclusion The MAPK/ERK pathway is essential for several cellular processes, such as apoptosis, cell cycle regulation, differentiation, and proliferation. Therefore, it has a critical role in tumourigenesis. Raf and MEK in particular are susceptible to inhibition, which has led to the production of several different drugs for use in various types of cancer. There are currently other clinical trials in progress, and these will hopefully lead to further therapies for other cancers involved in this pathway. Written by Eleanor R Markham Related articles: HIPPO signalling pathway / Thyroid cancer REFERENCES Lake, D., Corrêa, S.A.L. & Müller, J. Negative feedback regulation of the ERK1/2 MAPK pathway. Cell. Mol. Life Sci. 73 , 4397–4413 (2016). https://doi.org/10.1007/s00018-016-2297-8 Song Y, Bi Z, Liu Y, Qin F, Wei Y, Wei X. Targeting RAS-RAF-MEK-ERK signaling pathway in human cancer: Current status in clinical trials. Genes Dis. 2022 May 20;10(1):76-88. doi: 10.1016/j.gendis.2022.05.006. PMID: 37013062; PMCID: PMC10066287 Ullah R, Yin Q, Snell AH, Wan L. RAF-MEK-ERK pathway in cancer evolution and treatment. Semin Cancer Biol. 2022 Oct;85:123-154. doi: 10.1016/j.semcancer.2021.05.010. Epub 2021 May 13. PMID: 33992782. Project Gallery

Using toxins for pain management Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Anthrax Toxin Last updated: 18/09/25, 09:45 Published: 03/04/25, 08:00 Using toxins for pain management Introduction Pain is a response and signal to organisms that there is damage to the body. This could be due to an infection, tissue damage or organ damage. Different types of pain medication have been manufactured in the last decade. This includes the artificial manufacture of opioids, non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen, using pathogens like bacteria and other substances. Bacteria have been investigated for managing and treating pain, with varying levels of effectiveness. Research by Yang et al. (2021) has shown that bacteria can interact with organisms and communicate with the nervous system, leading to analgesia (pain relief). Bacteria can also activate nociceptors, receptors that respond to pain, to alert the organism of damage. These nociceptors can also detect bacterial processes that release pain-producing toxins. Yang et al.’s research specifically looked at the bacterial toxin Bacillus anthracis ( Figure 1 ). It is a significant factor in the spread of anthrax, an infectious disease, and their experiments showed that it can lead to analgesia, as Bacillus anthracis and nociceptors can work together to suppress pain. The experiment The experiment by Yang et al. looked at different methods to target and suppress specific nociceptive neurons to decrease pain in mammals using bacteria. The study focused on the interactions between nociceptors and Bacillus anthracis . The researchers found that Bacillus anthracis toxin was made up of three substances: protective antigen (PA), lethal factor (LF), and edema factor (EF), as shown in Figure 2 . They created edema toxin (ET) using PA and EF, and administered the ET to mice via the intrathecal route (through the spinal canal, also shown in Figure 2 ). The scientists used different doses of PA, LF and EF. The intrathecal route was used to limit the diffusion of ET to the spinal cord and sensory neurons, preventing ET from moving into other organs. The researchers then analysed the mouse neurons to compare the sequences before and after the experiments and determine the effectiveness of the treatments. The results indicated high levels of ANTXR2 receptors (high-affinity receptors for anthrax toxins), meaning the response to pain was faster. The results The researchers examined the mechanical sensitivity and thermal latency. Mechanical sensitivity is the ability to differentiate between and respond to mechanical stimuli, and thermal latency is the ability to differentiate between and respond to heat stimuli. In mammals, signs of pain can be quantified using these indicators. The higher the threshold, the lower the pain. The threshold levels of these factors were compared up to 24 hours after the injections of the PA, PA + LF and PA + EF, as shown in Figure 3. Figure 3 : Line graphs showing the results of the intrathecal injections. (A) Line graph of mechanical sensitivity thresholds after intrathecal administration. (B) Line graph of thermal sensitivity thresholds after intrathecal administration. (C) Line graph of mechanical sensitivity thresholds on the day and 24 hours after the second injection. After administration of the injections via the intrathecal route, thresholds of mechanical sensitivity, Figure 3A , were increased significantly for several hours. The injection of PA + EF resulted in the highest threshold, remaining at 1.0 g 6 hours post-injection, compared to the injections of PA and PA + LF, which both had a threshold of below 0.5 g 6 hours post-injection. The thresholds of thermal latency, shown in Figure 3B , also increased significantly for several hours. Again, the injection of PA + EF resulted in the highest latency, remaining for more than 20 seconds 6 hours post-injection, compared to the injections of PA and PA + LF, which both had a latency of below 20 seconds 6 hours post-injection. The results from Figures 3A and 3B suggest that the injections of PA + EF were the most effective in increasing the thresholds of both mechanical sensitivity and thermal latency. A second injection of ET was administered, and thresholds of mechanical sensitivity were again elevated, as shown in Figure 3C . After the second injection, the effects of pain relief were more potent. In the graph, at D2, the threshold of mechanical sensitivity 6 hours after the second injection was above 1.5 g for mice given ET, compared to below 1.0 g 6 hours after the first injection for mice given ET. This could be due to the upregulation of the ANTXR2 receptors induced by ET. Upregulation is when hormone secretion is suppressed, and the number of receptors (in this case, ANTXR2) increases, causing a faster response to the stimulus (in this case, pain). This suggests that ET can result in pain receptors being affected, leading to a faster analgesic response. The researchers concluded that this experiment did result in analgesia in mice as ET targeted specific nociceptors. The results from this experiment are significant because they indicate that pain behaviour can be blocked by intrathecal administration of a harmful bacterial toxin such as Bacillus anthracis . Conclusion Yang et al. (2021) found that the injection of the ET via the intrathecal route results in blocked pain behaviour in mice. The experiment is significant as it has shown that a harmful toxin can have positive effects. However, it is difficult to know if the effects will be replicated in humans as human trials have not yet been carried out. In addition, the sample size was very small, with a maximum of eight mice observed after each injection. This could result in high variability (the data points would be more spread out from the mean and, therefore, less consistent) and inconclusive results. Nevertheless, with further study, experimentation, and refinement of the ET via the intrathecal method, new therapies for people with pain, especially chronic pain, could be created in the future. Different dosages of the ET could be experimented upon to see whether a higher dosage has better results, with a bigger sample size, and human trials. The results from Yang et al. (2021) showed that intrathecal ET injections are promising, and if successful in humans, this method would ease the burden on healthcare systems worldwide. Written by Naoshin Haque Related articles: Ibuprofen / The Pain Gate Theory Project Gallery

The emperor penguin's life cycle is intertwined with sea ice freezing and melting over the year Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Emperor penguins, the kings of the ice Last updated: 29/03/26, 16:57 Published: 24/04/25, 08:00 The emperor penguin's life cycle is intertwined with sea ice freezing and melting over the year This is article no. 6 in a series on animal conservation. Next article: Protecting rock-wallabies in Australia . Previous article: Gorongosa National Park . In November 2024, a malnourished emperor penguin was spotted in Australia, over 2000 miles from its home in Antarctica. It is said to be the furthest north a wild emperor has ever been seen. While scientists do not know why or how the penguin ended up there, it sparked conversations about climate change and the survival of this fascinating species. This article will describe the characteristics of the emperor penguin, and how climate change could affect it. Introduction to emperor penguins Emperor penguins ( Aptenodytes forsteri ) are the largest living penguin species, weighing 20-40 kilograms and standing about 1 metre tall. It is estimated that there are around 260,000 breeding pairs of emperor penguins across 61 colonies, which are spread out along the entire coast of Antarctica. Their diet consists of krill, fish, and squid - and they can dive over 500m deep to find food. Emperor penguins are the only warm-blooded animal to breed during the Antarctic winter, one of the world's coldest and darkest times of the year. Therefore, they are adapted to the cold days, harsh winds, and high water pressure in which they live. For example, they have over 20 kinds of feathers - some of which help with waterproofing while swimming, and others help with thermal insulation. Many penguin species huddle together as juveniles to conserve body heat, but emperors are the only species to do so as adults. Thus, emperor penguins are a unique and ecologically fascinating species. Life cycle and fast ice The emperor penguin's life cycle is intertwined with sea ice freezing and melting over the year ( Figure 1 ). For most of the year, emperors live on fast ice, which are ice sheets floating on the sea but attached to the coast. The first reason they need fast ice is moulting, when emperor penguins replace all their feathers in late summer. They moult on ice because they cannot swim until their new layer of waterproof feathers has grown. Emperor penguins return to fast ice at the onset of winter to mate, lay eggs, and raise chicks. While one parent stays on the fast ice to look after the chick, the other parent goes to sea to find food for the family. The chick grows waterproof adult feathers for fast ice to break up in summer. At this point, the penguins live at sea until moulting time. This way, emperor penguin survival is linked to fast ice availability. Threat from climate change Because emperor penguins are so heavily dependent on fast ice, scientists are concerned about the potential impacts of global warming. Rising sea surface temperatures mean fast ice may not form long enough in the year for emperor penguins to complete their life cycle. In late 2022, sea ice was dramatically reduced in the Bellingshausen Sea in Antarctica, and 4 of the 5 nearby emperor penguin colonies had a failed breeding season. These failed seasons may become more common in the future with climate change. A 2020 study predicted that in the worst case climate scenario, 80% of penguin colonies will see population declines of over 90% by 2100. If international climate targets are met, only 19% of colonies are expected to decline that badly ( Figure 2 ). Because the International Union for Conservation of Nature classified emperors as Near Threatened, they do not meet Antarctica's criteria for being a protected species. Scientists have requested this conservation status be upgraded to better reflect the inability of emperor penguins to adapt or disperse away from the effects of climate change. Emperor penguins face no threats from humans other than global warming, so reducing greenhouse gas emissions is crucial to protect them. Conclusion Emperor penguins are charismatic creatures with unique adaptations to live during the cold Antarctic winter. Their survival is strongly linked to the availability of sea ice because they moult, breed, and care for their offspring on ice sheets. Global warming is making these ice sheets disappear, so emperor penguins must be monitored and protected to ensure survival through a changing climate. Written by Simran Patel Related articles: The Arctic Springtail / California Condors / Brain-climate connection REFERENCES CBS News. (2024) Malnourished emperor penguin that swam ashore in Australia 2,000 miles from home a quandary for rescuers. CBS News . Available from: https://www.cbsnews.com/news/emperor-penguin-australia-2000-miles-from-antarctic-ice-melting-climate-change/ (Accessed 11th November 2024). Fretwell, P.T., Boutet, A. & Ratcliffe, N. (2023) Record low 2022 Antarctic sea ice led to catastrophic breeding failure of emperor penguins. Communications Earth & Environment . 4 (1): 1–6. Garnier, J., Clucas, G., Younger, J., Sen, B., Barbraud, C., Larue, M., Fraser, A.D., Labrousse, S. & Jenouvrier, S. (2023) Massive and infrequent informed emigration events in a species threatened by climate change: the emperor penguins . Available from: https://hal.science/hal-03822288 (Accessed 10th November 2024). Hooper, S. (11th November 2024) Experts baffled after penguin shows up on beach 2,200 miles away from home Metro . Available from: https://metro.co.uk/2024/11/11/experts-baffled-penguin-shows-beach-2-200-miles-away-home-21970144/ (Accessed 11th November 2024). Fretwell, P. (2024) Four unreported emperor penguin colonies discovered by satellite. Antarctic Science , 36(4), 277–279. Jenouvrier, S. et al. (2020) The Paris Agreement objectives will likely halt future declines of emperor penguins. Global Change Biology . 26 (3): 1170–1184. Labrousse, S., Nerini, D., Fraser, A.D., Salas, L., Sumner, M., Le Manach, F., Jenouvrier, S., Iles, D. & LaRue, M. (2023) Where to live? Landfast sea ice shapes emperor penguin habitat around Antarctica. Science Advances . 9 (39): eadg8340. LaRue, M. et al. (2024) Advances in remote sensing of emperor penguins: first multi-year time series documenting trends in the global population. Proceedings of the Royal Society B: Biological Sciences . 291 (2018): 20232067. Le Maho, Y. (1977) The Emperor Penguin: A Strategy to Live and Breed in the Cold: Morphology, physiology, ecology, and behavior distinguish the polar emperor penguin from other penguin species, particularly from its close relative, the king penguin. American Scientist . 65 (6): 680–693. Trathan, P.N. et al. (2020) The emperor penguin - Vulnerable to projected rates of warming and sea ice loss. Biological Conservation . 241: 108216. Williams, C.L., Hagelin, J.C. & Kooyman, G.L. (2015) Hidden keys to survival: the type, density, pattern and functional role of emperor penguin body feathers. Proceedings of the Royal Society B: Biological Sciences . 282 (1817): 20152033. Project Gallery

Raymond et. al (1992), Shapiro (1994), and other studies Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link An exploration of the attentional blink in rapid serial visual presentation studies Last updated: 24/06/25, 15:01 Published: 03/07/25, 08:00 Raymond et. al (1992), Shapiro (1994), and other studies Attention is a cognitive mechanism that helps us select and process vital information while ignoring irrelevant information, enabling us to consolidate our memories. Attentional blink typically refers to the finding of a severe impairment for detection or identification of the second target (T2) of the two masked visual targets that occurs when the targets are presented within less than 500 milliseconds of each other. In this context, T1 refers to the first target, which captures attention and temporarily limits the ability to detect or identify T2 if they are presented too closely in time. Raymond et al. (1992) suggested that the attentional blink phenomenon is observed in rapid serial visual presentation (RSVP) conditions in which stimuli such as letters, digits or pictures are presented in a rapid sequence mostly at a single location. Typically, the target from the RSVP stimulus stream is differentiated (e.g. presented in a different colour), and the participant’s task is to identify the target. The RSVP procedure is a widely employed paradigm used to examine the temporal characteristics of perceptual and attentional processes. Shapiro (1994) proposed the interference theory as an explanation for attentional blink. According to the interference theory, there is a temporal buffer if many distractors are present. Due to the limitations of visual short-term memory, multiple items compete to be retrieved from this hypothetical temporal buffer, which can affect recall accuracy. As a result, attentional blink occurs due to competition over which target, T1 or T2, receives attentional processing. Supporting evidence comes from Isaak (1999), who presented combinations of letter and false-font stimuli per trial, and claimed that attentional blink magnitude increases if the competitors arise from the same conceptual category, for example, digits. Alternatively, Chun and Potter (1995) introduced their two-stage model to account for attentional blink. The aim of their research was to investigate whether attentional blink occurs in a Rapid Serial Visual Presentation (RSVP) task. Their hypothesis stated that participants’ ability to detect T2 would be reduced if it appeared approximately 300 milliseconds after T1. They also sought to examine whether attentional blink reflects a limited-capacity processing mechanism. The model suggests that stage 1 is where stimuli are processed and features and meanings are registered, but not at a sufficient level for report. In stage 2, the stimulus is consolidated for a response. The researchers reported that attentional blink occurs at stage 2, where identification and consolidation of T1 are slowed when there is a following item, delaying the processing of T2 after the onset of T1. Discussion Many RSVP studies hypothesise that presenting T2 300-700 milliseconds after T1, with multiple distractor items, increases the likelihood of attentional blink and impairs the ability to detect T2. This outcome aligns with Shapiro et al.’s (1999) interference theory, as participants faced significant difficulty retrieving stimuli from the temporal buffer during the dual task. However, participants demonstrated a higher success rate in identifying the target during the single task, even with rapid stimulus presentation. Additional support for the interference theory is provided by Raffone et al. (2014), who argued that T2 must be masked by a distractor, and if T1 appears within 500 milliseconds of T2, T2 often goes undetected, leading to attentional blink. The unified model further suggests that in RSVP tasks, attention allocation to T1 reduces the attention available for T2, leaving T2 susceptible to decay or substitution. This implies that attentional blink may result from T1 monopolising attentional resources and thus limiting the capacity to process T2, which explains the poorer performance observed in the dual task. Conclusions Despite their insights, both theories of attentional blink have notable shortcomings. There is contradicting evidence for the interference theory from Olivers and Meeter (2008), who believe that once attentional blink is induced by a first target, it can be alleviated if T2 is preceded by a non-target that shares a target-defining feature, such as having the same colour. Whereas, Reeves and Sperling (1986) postulate that an attentional gate is opened after T1 is detected and continues to remain open until target identification is complete. This can amplify the processing of the stimuli, enabling the identification of T1 and aiding T2 in receiving attentional processes and being identified accurately. A main limitation of the two-stage model for attentional blink studies is its difficulty in explaining the full spectrum of attentional blink effects, particularly the T1-sparing’ phenomenon and the impact of task demands on T2 processing. For instance, the two-stage model often assumes that T2 processing is solely impaired due to the attentional load of T1, but research suggests that the difficulty of the T2 task itself can influence the attentional blink. For example, if T2 requires a more complex or demanding response, the attentional blink effect may be more pronounced, even if T1 processing is relatively simple. Future research should investigate if attentional blink exists within other modalities, such as cross-modal perception (visual T1, auditory T2). This will enable us to get a deeper insight into how the attention mechanisms operate. Future research should also explore alternative explanations for the attentional blink. Some studies suggest it may not be solely attributable to resource limitations or processing bottlenecks but could instead reflect a more dynamic process involving attentional re-engagement or the interaction between perceptual and attentional systems. Written by Pranavi Rastogi REFERENCES Chun, M. M., & Potter, M. C. (1995). A two-stage model for multiple target detection in rapid serial visual presentation. Journal of Experimental Psychology: Human Perception and Performance, 21 (1), 109-127. doi:10.1037/0096-1523.21.1.109 Isaak, M. I., Shapiro, K. L., & Martin, J. (1999). The attentional blink reflects retrieval competition among multiple rapid serial visual presentation items: Tests of an interference model. Journal of Experimental Psychology: Human Perception and Performance, 25 (6), 1774-1792. doi:10.1037/0096-1523.25.6.1774 Olivers, C. N., & Meeter, M. (2008). A boost and bounce theory of temporal attention. Psychological Review, 115 (4), 836-863. doi:10.1037/a0013395 Raffone, A., Srinivasan, N., & Van Leeuwen, C. (2014). The interplay of attention and consciousness in visual search, attentional blink and working memory consolidation. Philosophical Transactions of the Royal Society B: Biological Sciences, 369 (1641), 20130215. doi:10.1098/rstb.2013.0215 Reeves, A., & Sperling, G. (1986). Attention gating in short-term visual memory. Psychological Review, 93 (2), 180-206. doi:10.1037/0033-295x.93.2.180 Raymond, J. E., Shapiro, K. L., & Arnell, K. M. (1992). Temporary suppression of visual processing in an RSVP task: An attentional blink? Journal of Experimental Psychology: Human Perception and Performance, 18 (3), 849-860. doi:10.1037/0096-1523.18.3.849 Shapiro, K. L., Raymond, J. E., & Arnell, K. M. (1994). Attention to visual pattern information produces the attentional blink in rapid serial visual presentation. Journal of Experimental Psychology: Human Perception and Performance,20 (2), 357-371. doi:10.1037/0096-1523.20.2.357 Project Gallery

The approval of targeted monoclonal antibodies starting in 2019 established a new standard of care for long-term relapse prevention. Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Comparing types of treatments for NMO Last updated: 30/09/26, 14:44 Published: 08/10/26, 08:00 The approval of targeted monoclonal antibodies starting in 2019 established a new standard of care for long-term relapse prevention. This is article no. 12 in a series on rare diseases. Next article coming soon. Previous article: CEDS: a break in cell death. Neuromyelitis optica spectrum disorder (NMOSD) is a rare and disabling autoimmune condition of the central nervous system that primarily attacks the optic nerves and spinal cord (see previous article for more). Symptoms include eye pain, blurred vision, weakness or paralysis in the limbs, muscle spasms, bowel disruptions etc. Before 2019, treatment options were limited to acute relapse management and off-label broad immunosuppression. This is done by stopping acute inflammatory attacks and using targeted maintenance therapies, such as monoclonal antibodies, to prevent relapses. However, the approval of targeted monoclonal antibodies starting in 2019 established a new standard of care for long-term relapse prevention. What are monoclonal antibodies? How does monoclonal antibody therapy work for NMOSD? Monoclonal antibodies (mAbs) are specialised, laboratory-engineered proteins designed to bind to precise cell surface receptors or soluble immune molecules, thereby interrupting specific pathogenic pathways responsible for driving neuroinflammation and tissue injury. In NMOSD, aquaporin-4 autoantibodies (AQP4-IgG) bind directly to astrocytes in the optic nerves and spinal cord, triggering severe localised inflammation, complement protein activation, and irreversible cell damage. Monoclonal antibody therapies block this destructive cascade through three distinct immunological mechanisms: Agents, such as inebilizumab and rituximab, target and deplete B-cell populations responsible for generating AQP4-IgG autoantibodies, thereby lowering circulating pathogenic antibody titers. Drugs like satralizumab and tocilizumab inhibit interleukin-6 (IL-6) receptors, stopping downstream inflammatory cascades that recruit damaging immune cells to central nervous system tissue. Terminal complement inhibitors, such as eculizumab and ravulizumab, block the C5 complement protein cascade, preventing antibody-mediated destruction of astrocytes and surrounding tissues. See Table 1 on the types of monoclonal antibody treatment for NMOSD, including mechanisms and efficacy. As of now, the above four monoclonal antibodies (apart from rituximab) (Table 1) have received U.S. Food and Drug Administration (FDA) approval for treating anti-aquaporin-4 (AQP4) antibody-positive NMOSD. Inebilizumab (Uplizna) is a humanized monoclonal antibody targeting CD19 on B cells, delivering broad depletion across early and mature B-cell populations. Satralizumab (Enspryng) acts as an interleukin-6 receptor antagonist that suppresses pro-inflammatory cytokine signaling networks. Complement inhibitors eculizumab (Soliris) and ravulizumab (Ultomiris) target the terminal complement C5 protein to stop the assembly of the membrane attack complex. Additionally, rituximab is a chimeric anti-CD20 monoclonal antibody widely prescribed off-label as a first-line preventive therapy due to extensive long-term clinical experience and documented real-world efficacy. When evaluating clinical efficacy and safety considerations, these targeted monoclonal therapies display their highest certainty of clinical benefit in patients who test positive for AQP4-IgG autoantibodies, though they are also utilised across the broader NMOSD spectrum. The primary safety concern associated with these biologic therapies is an increased risk of severe infections; notably, patients initiating complement inhibitor therapy require mandatory prior vaccination against meningococcal infection. Ultimately, selecting an appropriate monoclonal antibody depends on individual patient safety profiles, route and frequency of administration, drug availability, and cost factors. Future directions Despite the growing hope for the NMOSD community, it is necessary to be cautiously optimistic when interpreting these treatment options, as all currently approved monoclonal antibody therapies were tested and validated specifically for anti-aquaporin-4 antibody-positive (AQP4-IgG+) NMOSD. Broadly speaking, patients presenting with NMOSD-like syndromes fall into three distinct diagnostic categories based on autoantibody status. Approximately 70% to 80% of patients test positive for AQP4-IgG, representing a distinct astrocytopathy that responds exceptionally well to targeted complement and B-cell blockade. Another 10% to 20% of individuals with NMOSD-like presentations test positive for myelin oligodendrocyte glycoprotein antibodies (MOGAD), an entity involving primary oligodendrocyte damage that shows lower responsiveness to standard B-cell therapies. The remaining 10% to 20% are classified as double-seronegative NMOSD, a heterogeneous group lacking definitive biomarkers where monoclonal antibodies exhibit significantly reduced relative efficacy compared to AQP4-positive cases. While biologics have transformed care for AQP4-IgG positive disease, we still have a long way to go in uncovering the underlying mechanisms and developing targeted therapies for non-AQP4+ NMOSD. Written by Chloe Kam Related article: Introduction to NMO REFERENCES Pittock, S. J., Berthele, A., Fujihara, K., Kim, H. J., Levy, M., Palacio, A. J., ... & Wingerchuk, D. M. (2019). Eculizumab in Aquaporin-4–Positive Neuromyelitis Optica Spectrum Disorder. New England Journal of Medicine , 381(7), 614-625. Cree, B. A., Bennett, J. L., Kim, H. J., Weinshenker, B. G., Pittock, S. J., Wingerchuk, D. M., ... & N-MOmentum Study Group. (2019). Inebilizumab for the treatment of neuromyelitis optica spectrum disorder (N-MOmentum): a double-blind, randomised placebo-controlled phase 2/3 trial. The Lancet , 394(10206), 1352-1363. Yamamura, T., Kleiter, I., Fujihara, K., Palace, J., Greenberg, B., Zakrzewska-Pniewska, B., ... & SAkuraSky Study Group. (2019). Trial of Satralizumab in Neuromyelitis Optica Spectrum Disorder. New England Journal of Medicine , 381(22), 2114-2124. de Melo, A., et al. (2026). Monoclonal antibodies in neuromyelitis optica spectrum disorder: A systematic review and meta-analysis. BMC Neurology , 26 (1), 185. Häußler, V., Trebst, C., Engels, D., Pellkofer, H., Havla, J., Duchow, A., Schindler, P., Schwake, C., Pakeerathan, T., Fischer, K., Ringelstein, M., Lindenblatt, G., Hümmert, M. W., Tkachenko, D., Bütow, F., Giglhuber, K., Flaskamp, M., Schiffmann, I., Korporal-Kuhnke, M., Jarius, S., Dawin, E., Revie, L., Senel, M., Herfurth, M., & Walter, A. (2024). Real-world multicentre cohort study on choices and effectiveness of immunotherapies in NMOSD and MOGAD. Journal of Neurology, Neurosurgery & Psychiatry , 96 (6), 582. Zammar, K., Safan, A., Abushalbak, D. J., et al. (2026). Monoclonal antibody efficacy in seropositive vs seronegative NMOSD: Systematic review and meta-analysis. Journal of Neuroimmunology , 417 , 578945. Project Gallery

Symmetry in spectroscopy, reaction mechanisms and bonding Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link The importance of symmetry in chemistry Last updated: 02/04/26, 18:25 Published: 08/01/26, 08:00 Symmetry in spectroscopy, reaction mechanisms and bonding Introduction Symmetry is everywhere- in snowflakes, flowers and even art. Chemistry is no different and the symmetrical properties of a molecule often dictate its behaviour. From interpreting spectra, to predicting reaction pathways and understanding bonding, symmetry shapes all chemical disciplines. 1. Symmetry in spectroscopy Firstly, understanding the symmetry of molecules is essential in a range of characterisation techniques. In 1 H NMR spectroscopy, the number of peaks seen in a spectrum correspond to the number of unique chemical environments. For example, dibenzylidene acetone has a plane of symmetry and a rotational axis (C 2 ) through the centre of the carbonyl. This explains why the spectrum only has 5 different proton environments. In IR spectroscopy, infrared radiation is absorbed by a molecule causing stretching and bending of bonds when they vibrate. The total number of vibrational modes can be predicted using: • 3N – 5 rule for linear molecules • 3N – 6 rule for non-linear molecules (where N = no. of atoms) However, only vibrations which cause a change in dipole moment are seen in IR spectra. This explains why CO 2 only shows 3 main absorption peaks, despite having 4 vibrational modes. 2. Symmetry in reaction mechanisms Considering the symmetry of molecules also helps chemists predict the stereochemical outcome of organic reactions. A common example is the E2 elimination of a halogenoalkane, where an alkene is formed via elimination of a halogen. For an E2 elimination to occur, the H and the leaving group must be 180 ° from each other, in an ‘anti-periplanar’ conformation. To predict which groups, have this relationship, Newman projections are used to easily assign and rotate bonds. A Newman projection is a perspective of a molecule, typically by imagining you are looking down a specific C-C bond. See Figure 3 . 3. Symmetry in bonding Lastly, considering the symmetry of a molecule is vital for understanding Molecular Orbital (MO) Theory. MO theory explains how covalent bonding occurs by considering the symmetry elements of the valence orbitals. For example, in H 2 , the two valence 1s orbitals are completely symmetric and therefore can overlap effectively to form a σ molecular orbital. However, in HF, the introduction of 2p orbitals means the shape and symmetry has changed. The 2p x and 2p y orbitals can no longer overlap with the 1s H orbital as their symmetries are incompatible. Using this information, a MO diagram can be constructed to show how the orbitals combine, explaining why H 2 has a single bond. In essence, symmetry determines which orbitals can ‘match up’ to form bonds. See Figure 4 . Conclusion Symmetry influences every aspect of chemistry and is frequently employed to rationalise observed molecular characteristics. While sometimes overlooked, considering the symmetry of a molecule underpins any chemistry undertaken across industry and academia. If you enjoyed this article, future articles could build on this topic by introducing Group Theory and showing how you can predict an entire vibrational spectrum, or the molecular geometry of a compound based entirely on its symmetry. Written by Antony Lee Related article: Diels-Alder reaction REFERENCES S. Civis, M. Ferus, A. Knizek, in The Chemistry of CO 2 and TiO 2 : From Breathing Minerals to Life on Mars, ed. S. Civis, M. Ferus, A. Knizek, Springer Nature, Switzerland, 1 st edn., 2019, vol. 1, ch. 1, pp. 1-7 A. Burrows, J. Holman, S. Lancatser, T. Overton, A. Parsons, G. Pilling, G. Price, in Chemistry 3 , Oxford University Press, Oxford, 3 rd edn., 2017, ch.4, pp. 172-219 Project Gallery

Considering how non-covalent interactions can govern the way molecules recognise and organise themselves Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Chemistry Beyond the Molecule (Supramolecular Chemistry) Last updated: 06/09/26, 11:47 Published: 17/09/26, 08:00 Considering how non-covalent interactions can govern the way molecules recognise and organise themselves Introduction How many times have you performed a reaction and ignored the solvent? Or failed to consider the potential interactions between each reagent, or between the solvent and reagents? As chemists, we are often guilty of focusing on the molecules undergoing the reaction and treating everything else as background. Although this approach is intuitive, molecular behaviour is also influenced by interactions with surrounding molecules. To truly understand a system, we must therefore look ‘beyond the molecule’. Supramolecular chemistry, or ‘chemistry beyond the molecule’, was described by Jean- Marie Lehn as the ‘chemistry of the intermolecular bond’. Broadly, this means considering how non-covalent interactions can govern the way molecules recognise and organise themselves. Although these interactions are individually weaker than covalent bonds, their combined effects can have profound consequences, from stabilising the structures of proteins and DNA to directing the assembly of larger molecular systems. Choosing solvents Perhaps the most common synthetic application of supramolecular chemistry regards the selection of solvents. While frequently overlooked, selecting the correct solvent can have a direct impact on reaction kinetics and success, particularly with regards to SN1 and SN2 reactions. For example, let’s consider a simple SN1 reaction between 2-bromo-2-methylpropane and sodium chloride in water. Water is considered a polar protic solvent and is therefore well suited to facilitating an SN1 mechanism. Mechanistically, the first step involves the loss of the bromide leaving group to form a carbocation intermediate. Water facilitates this process through its intermolecular interactions with the charged species involved. As a polar protic solvent, water can act as a hydrogen bond donor and solvate the departing bromide ion. More importantly, water can stabilise the developing positive charge via ion-dipole interactions with the oxygen lone pairs orientated towards the carbocation. This stabilises the transition state, reducing the activation barrier of the rate determining step ( Figure 1 ). Note- competing reaction: Although water stabilises the carbocation intermediate and solvates the bromide leaving group, it is also a nucleophile. In an aqueous solution, water is present at a very high concentration and can directly trap the tert-butyl carbocation. Consequently, 2-bromo-2-methylpropane undergoes solvolysis, producing 2-methyl-2-propanol (tert-butanol). Chloride ions from NaCl can potentially compete as nucleophiles. Alternatively, SN2 reactions are known to be accelerated by polar aprotic solvents. This is not surprising when you consider the differences in reaction mechanism. Unlike protic solvents, aprotic solvents cannot act as hydrogen bond donors. Therefore, the nucleophile is less strongly solvated, accelerating the rate of nucleophilic attack ( Figure 2 ). Introducing crown ethers and cryptands In 1987, the Nobel Prize in chemistry was awarded to Cram, Pedersen and Lehn for their work on supramolecular chemistry. This section will focus on the development of crown ethers and cryptands by Pedersen and Lehn, respectively. A crown ether is a macrocyclic molecule containing multiple oxygen atoms within its ring. The arrangement of these atoms creates a specific sized cavity which can selectively bind alkali metal ions through ion-dipole interactions. The size and geometry of this cavity play an important role in determining which ions can be most effectively accommodated. For example, consider the molecule 18-crown-6, known for effectively binding potassium ions. The name 18-crown-6 refers to its 18-membered ring, of which 6 atoms are oxygen. Its cavity diameter of 2.60-3.20 Å matches the diameter of a potassium cation (2.66 Å) favouring strong binding. However, the strength of this interaction is also dependent on the surrounding solvent ( Figure 3 ). The selectivity of crown ethers can be demonstrated by comparing 18-crown-6 with 15- crown-5. The smaller cavity of 15-crown-5 is better suited to the smaller sodium ion, illustrating how subtle changes in molecular structure can influence which ions a molecule recognises and binds. Cryptands take this principle a step further. Like crown ethers, they can bind alkali metal ions, but their 3D macrocyclic structure creates a more enclosed cavity ( Figure 4 ). The 3D structure of the cryptand provides significant advantages over the crown ether. Its donor atoms are preorganised around the cavity, reducing the structural rearrangement required to bind the ion. Once bound, the metal ion is encapsulated within a cage, making dissociation more difficult. Synthetically, crown ethers and cryptands can exploit this strong binding to separate an alkali metal cation from its counterion. This is particularly useful for reactions involving bases. By selectively complexing the cation, the nucleophilicity of the base increases, improving its efficiency within a given reaction ( Figure 5 ). Mechanically interlocked molecules The power of supramolecular chemistry is often the ability to direct molecular self-assembly through several simultaneous intermolecular interactions. Synthetically, this has been exploited to create a range of interesting molecular structures and topologies, including catenanes and rotaxanes. A catenane is a mechanically interlocked molecule (MIM) formed when two or more macrocyclic rings become intertwined. The rings are described as interlocked because they cannot separate without breaking a covalent bond. The ring structures form selectively through favourable intermolecular interactions. One example is Stoddart’s synthesis of a catenane containing a cyclobis(paraquat-p- phenylene) ring, commonly known as the ‘blue box’. The electron-deficient bipyridinium units within the ‘blue box’ interact favourably with electron-rich aromatic groups in the second macrocycle. These favourable donor-acceptor interactions help orient each component before the final covalent bonds are formed ( Figure 6 ). Another example of a MIM is the rotaxane. Rather than two rings being interlocked, a rotaxane consists of a macrocyclic ring threaded onto a linear molecular ‘axle’. Bulky groups are used at the ends of the ‘axle’ to prevent the ring slipping off. Again, the macrocyclic ring can move along the ‘axle’, with its position determined by favourable intermolecular interactions ( Figure 7) . Conclusion Supramolecular chemistry broadens our understanding of how intermolecular interactions influence chemical behaviour, extending this perspective from the bulk properties of matter to the behaviour and organisation of individual molecules. From solvent selection to molecular topology, supramolecular chemistry is a powerful tool to understand reaction outcomes and design complex molecular structures. This article serves as an introduction to a broad field of active research, with exciting applications in dynamic combinatorial synthesis and molecular machinery. Written by Antony Lee Related article: Chemistry beyond carbon REFERENCES The Nobel Prize - https://www.nobelprize.org/prizes/chemistry/1987/summary/ (Accessed August 2026) VedPrep - https://www.vedprep.com/exams/uppsc/crown-ethers-in-s-block- elements/ (Accessed August 2026) S. Massa et al., Archiv der Pharmazie, 1993, 326, 539-546 G.G. Ramirez et al., Angew. Chem. Int. Ed. Engl., 2015, 54, 6110-6150 F. Stoddart et al., Eur. J. Org. Chem., 1998, 45, 2565-2571 Project Gallery

Civil wars and arms trade Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Yemen- a neglected humanitarian crisis Last updated: 03/05/26, 18:20 Published: 15/05/25, 08:00 Civil wars and arms trade This is article no. 3 in a series about global health injustices. Previous article: Civil war in Sudan . Next article: Injustices in Lebanon and Syria . Introduction Welcome to the third article of the Global Health Injustices Series. Building on the last article on Sudan , the focus is now on Yemen, by analysing the health inequalities and inequities the broader Yemeni population encounters. Similar to Sudan, there is a civil war between the government and the Houthis, among other political factions in Yemen, producing detrimental population health outcomes that will be delved into after an overview of Yemen's history and current state. Yemen: a distinct past and its current challenges Yemen is a country in the Middle East bordered by Saudi Arabia and Oman. Like Palestine and Sudan, Yemen is noteworthy for its distinct culture, languages and traditions. Moreover, Yemen has been part of trade routes with other surrounding countries for centuries and even now, as it is adjacent to the Red and Arabian Seas. However, as far back as the 1990s, when Yemen gained independence after varying degrees of resisting colonialism, internal friction within the government has led to civil wars even before this current one. At the moment, Yemen has one of the highest rates of mal- and undernutrition in the Middle East due to approximately half of the Yemeni people living in poverty and lacking access to clean water. Additionally, around 4.5 billion people are displaced in Yemen, and have been displaced in many instances since 2015. Furthermore, in spite of the ongoing civil war, Yemen has at least 97,000 asylum seekers and refugees from countries like Somalia and Ethiopia. Taking into account this important context, it is vital to support the Yemeni population as well as the refugees and asylum seekers. This is because they are facing injustices, which then lead to worsening outcomes for numerous people in Yemen. Although this crisis is ongoing, the Yemeni people, the refugees and asylum seekers stay resilient within their communities. Civil war and the consequences of the arms trade Unfortunately, Yemen has been noted by the WHO as an ignored humanitarian crisis, where approximately 20 million people need emergency healthcare. Specifically, 17.3 million people are driven to starvation, including 1.15 million children under 5 years old being acutely malnourished, having a 30-50% mortality risk. Although these statistics are driven by the ongoing civil war fueled by the arms trade between the Yemeni government, others in the Middle East and notably the United States, it is essential to highlight the other factors in Yemen driving childhood malnutrition. One study found that as maternal education, social and economic status increase, the likelihood of malnutrition in children decreases. Moreover, cigarette smoking during pregnancy increased the number of children with malnutrition. It could be inferred that there was a lot of internal instability within Yemen when this study occurred, leading to these health outcomes for the children, which have been currently worsened by the ongoing civil war, with further fuel from the arms trade. Regarding mental health in Yemen, one article noted how the COVID-19 pandemic, on top of the civil war, has impacted access to mental health care. Approximately 20% of Yemenis suffer from at least one mental health disorder, which includes anxiety, depression and schizophrenia. However, seeking help for mental health has been hindered by stigma and superstition, notably how people with these concerns may be described as dangerous. These gaps underline a lack of resources and facilities in Yemen attributed to damage from the ongoing civil war. Shifting to infectious diseases, the civil war in Yemen has contributed to a high burden of neglected tropical diseases (NTDs), which are diseases affecting low-income countries that lack healthcare resources, infrastructure and sanitation and hygiene facilities. The most notable include dengue fever, salmonella, and schistosomiasis ( Figure 1 ). The exact epidemiological data of NTDs in Yemen is difficult to find because there is a lack of infectious disease surveillance, and the healthcare system is fractured. Focusing on Yemen’s healthcare system, one review noted six key areas from the World Health Organisation that are involved in a strong healthcare system: health information systems, health workforce, governance, service delivery, access to essential medicines, and financing. Each area is weakened by the civil war, but here is a glimpse of each area, with some of the steps forward. Firstly, the review suggested that health information systems are deficient, so the authors urged the creation of a health survey system for Yemen. Since 2015, the health workforce has decreased by 50%, where more than half of workers left their jobs as they were not getting paid; retaining them could be through voucher programs and payment contracts. Also, access to essential medicines, particularly for chronic diseases, is scarce due to lack of funding, limited imports and damage to infrastructure. As for service delivery, at least 50% of healthcare buildings are operating, with airstrikes destroying more than 500 buildings, leaving vital services like emergency obstetric care very restricted. Although financing on healthcare has increased from 0.8% in 2004 to approximately 2.9-4.1%, with further investment to up to 12%, the population still has to pay out-of-pocket for healthcare. To move forward, the author noted how crucial it is to increase government spending on health. However, enhancing these areas must begin with improving governance, or the key leaders in Yemen congregating to make decisions that lead to a more robust healthcare system. Currently, there are issues due to bureaucracy, top-down management and friction between the Yemeni government, the Houthis and the other political factions. As mentioned above, one area of service delivery severely impacted by the ongoing war is obstetric care, along with newborn and child health. One case study noted that although these areas are a priority, there were instances, like tackling cholera outbreaks ( Figure 2 ) and treating malnutrition, which were offered priority over other forms of care. This imbalance reflects that more funding is required for all of the healthcare service areas to run optimally. One way forward is to include not only the leaders in Yemen, but also international NGOs to bring in their expertise to support the re-development of the healthcare system. The role of NGOs in supporting the Yemeni population NGOs have a vital role in supporting vulnerable populations, especially in Yemen. In a 2025 report from Amnesty International, they noted several breaches of international law and human rights: Parties to the conflict in Yemen continued to arbitrarily detain, forcibly disappear and unjustly prosecute people who criticized their human rights records and policies, including human rights defenders, journalists and humanitarian workers. All parties to the conflict failed to protect economic and social rights amid international funding cuts that further worsened the humanitarian crisis. Parties to the conflict contributed to environmental degradation. Other NGOs, such as the United Nations High Commissioner for Refugees (UNHCR), stated their provision of lifesaving aid to refugees, asylum seekers and displaced Yemenis, along with other forms of support through cash and essential supplies. The first way forward towards upholding the health and wellbeing of the broader population is to establish clearer governance among the leaders in Yemen. This could be facilitated by NGOs and other stakeholders, perhaps the other governments too, by stopping arms trade and increasing humanitarian aid. Conclusion: looking ahead at clearer governance Throughout this article, evidence indicates that the civil war in Yemen has devastating impacts on the health and wellbeing of the population. From individuals unable to seek appropriate mental health support, to a divided healthcare system with limited funding and other deficits. Consequently, the leaders in Yemen must come together to uphold international law and human rights, while NGOs are vital in facilitating this dynamic. My previous words on holding people in power worldwide accountable to human rights and international law are very relevant for Yemen. This is because they are responsible for enabling the ongoing civil war through the arms trade, so urging these people in power, particularly in Western countries, to stop would be a major step forward in de-escalating the humanitarian crisis. For the next article in the Global Health Injustices Series, it will be a collaborative endeavour that focuses on both Syria and Lebanon, two bordering countries that have diverging yet connected struggles; by understanding them, we can ensure that the populations in both countries obtain as much support as possible to improve their health outcomes. Written by Sam Jarada Related article: Understanding health through different stances REFERENCES UNHCR. Yemen Crisis Explained. 2024. Available from: https://www.unrefugees.org/news/yemen-crisis-explained/ WHO. Achieving health for all in Yemen. 2023. Available from: https://www.emro.who.int/images/stories/yemen/achieving-health-for-all-in-yemen.pdf Capitalizing on Conflict: How U.S. arm sales fuel the humanitarian crisis in Yemen. OpenSecrets. 2024. Available from: https://www.opensecrets.org/news/reports/capitalizing-on-conflict/yemen-case-study Sunil TS. Effects of socio‐economic and behavioural factors on childhood malnutrition in Yemen. Maternal and Child Nutrition. 2009 Feb 3;5(3):251–9. Available from: https://onlinelibrary.wiley.com/doi/epdf/10.1111/j.1740-8709.2008.00174.xm Waleed Alhariri, Mcnally A, Knuckey S. The Right to Mental Health in Yemen: A Distressed and Ignored Foundation for Peace. Health and Human Rights. 2021 Jun;23(1):43. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC8233030/ Ahmed A, Rahmat Dapari, Dom NC. Neglected tropical diseases in Yemen: a systematic review of epidemiology and public health challenges. BMC Public Health. 2025 Feb 7;25(1). Available from: https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-025-21700-z#Fig3 Ali Alraimi A, Shelke A. Strengthening Health Systems in Conflict: Evidence-Based Policies for Quality Care in Yemen. Journal of Cardiovascular and Cardiology. 2024 Mar 31;1–4. Available from: https://oaskpublishers.com/assets/article-pdf/strengthening-health-systems-in-conflict-evidence-based-policies-for-quality-care-in-yemen.pdf Tappis H, Elaraby S, Shatha Elnakib, Abdulghani A, Huda BaSaleem, Saleh A, et al. Reproductive, maternal, newborn and child health service delivery during conflict in Yemen: a case study. Conflict and Health. 2020 May 27;14(1). Available from: https://conflictandhealth.biomedcentral.com/articles/10.1186/s13031-020-00269-x Human rights in Yemen. Amnesty International. 2023. Available from: https://www.amnesty.org/en/location/middle-east-and-north-africa/middle-east/yemen/report-yemen/ Project Gallery

Exploring the microscopic world of molecules Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Quantum Chemistry Last updated: 05/02/26, 10:12 Published: 06/02/25, 08:00 Exploring the microscopic world of molecules Quantum chemistry provides a glimpse into the strange and fascinating world of molecules and atoms, where the principles of traditional chemistry and physics no longer apply. While classical chemistry can explain molecular interactions and bonding, it cannot fully account for particles' unusual, frequently contradictory behaviour at the atomic and subatomic levels. Quantum mechanics provides scientists with a powerful framework for understanding the complicated behaviour of electrons and nuclei in molecules. The basics of quantum chemistry The notion of wave-particle duality, which states that particles, such as electrons, act not just like objects with mass but also like waves, is central to quantum chemistry. Because the exact position and momentum of an electron cannot be known at the same time (according to the Heisenberg Uncertainty Principle), probability distributions are used to describe electrons rather than accurate orbits. These distributions are represented by mathematical functions known as wave functions, which describe the probability of finding an electron in a specific location surrounding the nucleus. This fundamentally affects our understanding of chemical bonding. Instead of conceiving a bond as a solid connection between two atoms, quantum chemistry defines it as the overlap of electron wave functions, which can result in a variety of molecular topologies depending on their energy levels. Quantum mechanics and bonding theories Quantum mechanics has fundamentally altered our knowledge of chemical bonding. The classic Lewis structure model, which explains bonding as the sharing or transfer of electrons, is effective for simple molecules but fails to convey the complexities of real-world interactions. In contrast, quantum chemistry introduces the concept of molecular orbitals. In molecular orbital theory, electrons are not limited to individual atoms but can spread across a molecule in molecular orbitals, which are combinations of atomic orbitals from the participating atoms. These molecular orbitals provide a more detailed explanation for bonding, especially in compounds that do not match simple bonding models, such as delocalised systems like benzene or metals. For example, quantum chemistry explains why oxygen is paramagnetic (it possesses unpaired electrons), a characteristic that classical bonding theories cannot explain. Quantum chemistry and quantum computing One of the most interesting frontiers in quantum chemistry is its application to the development of quantum computers. Traditional computers, despite their enormous processing power, struggle to model the complicated behaviour of molecules, particularly large ones. This is because simulating molecules at the quantum level necessitates tracking all conceivable interactions between electrons and nuclei, which can quickly become computationally challenging. Quantum computers use fundamentally different ideas. They employ qubits, which, unlike classical bits, can exist in a state of both 0 and 1. This enables quantum computers to execute several calculations concurrently and manage the complexity of molecular systems considerably more effectively. This could lead to advancements in quantum chemistry, such as drug discovery, where precisely modelling molecular interactions is critical. Instead of depending on trial and error, scientists may utilise quantum computers to model how possible pharmaceuticals interact with biological molecules at the atomic level, thereby speeding up the creation of novel therapies. Similarly, quantum chemistry could help in the development of novel materials with desirable qualities, such as stronger alloys and more efficient energy storage devices. Why quantum chemistry matters The consequences of quantum chemistry go well beyond the lab. Understanding molecular behaviour at its most fundamental level allows us to create new technologies and materials that have an impact on everyday life. Nanotechnology, for example, relies largely on quantum principles to generate innovative materials with applications in medicine, electronics, and clean energy. Catalysis, the technique of speeding up reactions, also benefits from quantum chemistry insights, making industrial operations more efficient, such as cleaner fuel generation and more effective environmental remediation. Furthermore, quantum chemistry provides insights into biological processes. Enzymes, the proteins that catalyse processes in living organisms, work with a precision that frequently defies standard chemistry. Tunnelling, quantum phenomena in which particles slip past energy barriers, helps to explain these extraordinarily efficient biological processes. In brief, quantum chemistry provides the fundamental understanding required to push the limits of chemistry and physics by exposing how molecules interact and react in ways that traditional theories cannot fully explain. Quantum chemistry has the potential to radically alter our understanding of the microscopic world, whether through theoretical models, practical applications, or future technology advancements. Written by Laura K Related articles: Quantum computing / Topology / Computational organic chemistry Project Gallery