Examining disconnection strategies and Functional Group Interconversion (FGI) Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Molecular blueprints: the art of synthetic planning Last updated: 05/03/26, 14:47 Published: 19/02/26, 08:00 Examining disconnection strategies and Functional Group Interconversion (FGI) This is article no. 1 in a two-part series on retrosynthesis. Next article: Synthesis of ibuprofen . Introduction Science is often seen as rigid, driven solely by facts and logic. Yet, in the world of chemical synthesis, molecular design and retrosynthetic analysis can be considered an art form. Synthetic creativity can be measured by the number of steps, environmental considerations, or the clever assembly of chemical building blocks. Widely used in the pharmaceutical industry and responsible for many Nobel Prize‑winning discoveries, retrosynthetic planning is central to modern synthetic chemistry. 1. Disconnection Strategy Retrosynthesis begins with deconstructing a target molecule into simpler starting materials known as synthons. A synthon is hypothetical but represents a fragment that could react to form a target molecule. Chemists then match synthons to real‑life equivalents (R.L.E.) which can be used in the lab. For example, if a target molecule contains an ester group, cleaving the oxygen–carbonyl bond produces four possible synthons ( Figure 1 ). Of these synthons, the positively charged oxygen has no R.L.E., so pairing the negatively charged oxygen with a carbonyl‑containing R.L.E., such as a carboxylic acid or acid chloride, and an alcohol will effectively synthesise the desired ester. 2. Functional Group Interconversion (FGI) FGIs are exploited by chemists when a functional group is difficult to manipulate directly. In these cases, the target functional group is converted to another functional group which is easier to work with. For instance, this strategy is commonly used to synthesise alkene and carboxylic acid fragments. As alkenes mainly participate in addition reactions, forming C–C bonds can prove difficult; therefore, converting the alkene to an alkyne can make this simpler. As an alkyne‑to‑alkene transformation is relatively simple, using either Lindlar’s catalyst (Z‑alkene) or Na/NH₃ (E‑alkene), alkynes can be used to build up the carbon chain before a final reduction. This is done by simple nucleophilic substitutions promoted by base deprotonation (NaNH₂) of the alkyne. The same idea is used for installing carboxylic acids, as a common FGI is to use a nitrile group (CN). These can be easily transformed back to the target carboxylic acid using acid in aqueous conditions. 3. Synthesis of Aspirin Retrosynthetic analysis can be used to design synthetic routes to common pharmaceuticals. For aspirin, a good disconnection strategy would be to break the ester bond and derive R.L.E. as shown above. To install the carboxylic acid, an FGI can be used. In Figure 3, two possible syntheses are highlighted utilising these strategies. While the synthetic methods presented previously will produce aspirin in high yields, they often create large amounts of waste and use harsh acidic conditions. Bhuyan et al. have proposed a more sustainable synthesis using blue LED light to catalyse the reaction under an O₂ atmosphere ( Figure 4) . Conclusion In conclusion, retrosynthesis and synthetic planning are essential tools for designing complex molecules. While the disconnection strategy and FGIs are relatively simple concepts, their application is used routinely in both industry and academia, regardless of the complexity of the target molecule. While one strategy may be used routinely, there are often many more ways to synthesise a particular compound more efficiently or with more flair. Stay tuned for Part 2, where the techniques discussed here are applied to the synthesis of ibuprofen. Written by Antony Lee Project Gallery

The lunar terrain Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link A love letter from outer space: Lonar Lake, India Last updated: 09/10/25, 11:05 Published: 10/04/25, 08:00 The lunar terrain Around 50,000 years ago, outer space gifted the earth with a crater that formed the foundations of the world’s third largest natural saltwater lake, situated within a flat volcanic area known as the Deccan Plateau. This resulted from a 2 million tonne meteorite tunnelling through the earth’s atmosphere at the velocity of 90,000km/hour and colliding into the Deccan Plateau. As time slipped away, pressure and heat melted the basalt rock tucked underneath the impact, and the accumulation of rainwater filled the crater with water. These foundations curated what is famously known today as the ‘Lonar Lake’. What is unique about the Lonar Lake is that it is the only meteorite-crater formed in basaltic terrain - synonymous to a lunar terrain. Additionally, the remnants bear similarities to the terrestrial composition of Mercury, which contains craters, basaltic rock and smooth plains resulting from volcanic activity. Many speculations have arisen to prove the theory of the crater forming from the impact of a meteorite. One such collaborative study conducted by The Smithsonian Institute of Washington D.C. USA, the Geological Survey of India and the US Geological Survey involved drilling holes at the bottom of the crater and scrutinising the compositions of rock samples sourced from the mining. When tested in the laboratory, it was found that the rock samples contained leftovers of the basaltic rock that were modified from the crater collision under high heat and pressure. In addition, shattered cone-shaped fractures, due to high velocity shock waves being transmitted into the rocks, were identified. These two observations align with the meteorite impact phenomenon. Additionally, along with its fascinating astronomical properties, scientists have been intrigued by the chemical composition of the lake within the crater. Its dark green colour results from the presence of the blue-green algae Spirulina. The water also has a pH of 10, making the water alkaline in nature, supporting the development of marine systems. One explanation for the alkalinity of the water is that it is a result of immediate sulphide formation, where the groundwater of meteorite origin contains CO2 undergoes a precipitation reaction with alkaline ions, leaving a carbonate precipitate with an alkaline nature. What is also striking about the composition of the water as well is its saline nature, which coexists with the alkaline environment - a rare phenomenon to occur in ecological sciences. The conception of the lake, from the matrimony of Earth with the debris within outer space, has left its imprints within the physical world. It's a love letter, written in basaltic stone and saline water, fostering innovation in ecology. The inscription of the meteorite’s journey within the crater has branched two opposing worlds, one originating millions of miles away from humans with one that resides in the natural grounds of our souls. Written by Shiksha Teeluck Related articles: Are aliens on Earth? / JWST / The celestial blueprint of time: Stonehenge REFERENCES Taiwade, V. S. (1995). A study of Lonar lake—a meteorite-impact crater in basalt rock. Bulletin of the Astronomical Society of India, 23, 105–111. Tambekar, D. H., Pawar, A. L., & Dudhane, M. N. (2010). Lonar Lake water: Past and present. Nature Environment and Pollution Technology, 9(2), 217–221. Project Gallery

Investigating the different mechanisms that can lead to high blood pressure Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link What really happens inside the body during high blood pressure Last updated: 08/10/26, 18:55 Published: 08/10/26, 08:00 Investigating the different mechanisms that can lead to high blood pressure Introduction Hypertension is often described in simple terms - a number on a screen or a diagnosis made in clinical practice. Yet behind these readings lies a complex network of underlying biological processes. Long before complications arise, subtle changes in the kidneys, blood vessels, and hormonal systems begin to disrupt the body’s ability to regulate blood pressure. Understanding these mechanisms reveals how hypertension develops and why it remains one of the most pressing challenges in modern health. Cardiac output and peripheral resistance Blood pressure is maintained through a balance between cardiac output and peripheral resistance. Cardiac output is the volume of blood pumped per minute, and peripheral resistance is the resistance to blood flow in the peripheral vasculature. In most individuals with hypertension, cardiac output remains relatively normal. Instead, the problem lies with increased resistance in circulation. This resistance is primarily controlled by small blood vessels known as arterioles, which have muscular walls that can constrict or relax to regulate blood flow. Contraction of these muscles is driven partly by increased intracellular calcium, which causes the vessels to narrow and increases resistance. Excess sodium intake further contributes by increasing fluid volume and making blood vessels more likely to constrict ( Figure 1 ). Over time, persistent vasoconstriction can lead to structural changes in the vessel walls, causing them to thicken and become less flexible. Hormones such as angiotensin contribute to this process, resulting in a sustained and often irreversible increase in peripheral resistance. Renin-angiotensin system One of the most important hormonal systems involved in blood pressure regulation is the renin-angiotensin system. This system is activated when the body senses a drop in blood flow, reduced salt intake, or increased sympathetic activity. In response, the kidneys release renin, an enzyme that converts angiotensinogen to angiotensin I ( Figure 2 ). Angiotensin I is then converted to angiotensin II in the lungs. Angiotensin II plays a central role in raising blood pressure and stimulates the release of the hormone aldosterone from the adrenal gland, which promotes sodium and water retention in the kidneys. Together, these effects increase both vascular resistance and blood volume, leading to a rise in blood pressure. People with high blood pressure do not always have low renin levels. Some have normal renin levels because the kidneys are not strongly activated to change renin release. In contrast, others have high renin levels because reduced blood flow to parts of the kidney stimulates renin release. In some cases, this can be due to underlying kidney or hormonal diseases. Autonomic nervous system The autonomic nervous system (ANS) also plays an important role in regulating blood pressure by controlling how wide or narrow blood vessels are. During stress or physical activity, the sympathetic nervous system (SNS), one division of the autonomic nervous system, is activated, causing the release of noradrenaline and adrenaline. These hormones increase heart rate and cause blood vessels to narrow (vasoconstriction), resulting in an increase in blood pressure. Although this response is important for short-term blood pressure regulation, it is not the main cause of chronic hypertension. However, overactivity of the SNS can contribute to persistently high blood pressure. Their role still remains significant, as drugs that reduce sympathetic activity are effective in lowering blood pressure. For example, adrenergic drugs such as beta-blockers act as sympatholytics by blocking the effects of noradrenaline at adrenergic receptors in the heart and blood vessels, reducing heart rate and how strongly the heart pumps, which decreases blood pressure. This highlights the contribution of the autonomic nervous system to hypertension. Endothelium dysfunction The endothelium, the inner lining of the blood vessels, is another key regulator of vascular function. In hypertension, the endothelium becomes dysfunctional, both contributing to and resulting from high blood pressure. Factors such as smoking, diabetes, and high cholesterol can contribute to this process. A key feature of endothelial dysfunction is reduced production of nitric oxide, a molecule that promotes vasodilation. With less nitric oxide available, blood vessels are less able to dilate, which increases resistance and sustains high blood pressure. Oxidative stress further worsens this process by generating reactive oxygen species (ROS) that damage the endothelium and reduce the availability of nitric oxide, creating a cycle that reinforces hypertension. ROS are generated as by-products of mitochondrial metabolism, and their levels increase under conditions of inflammation and metabolic stress. Insulin resistance Insulin resistance is also strongly associated with hypertension. It contributes through several mechanisms, including increased sympathetic activity, sodium retention, and structural changes in blood vessels. Importantly, insulin normally promotes vasodilation, but in individuals with hypertension, this effect is impaired, leading to increased vascular resistance. Genetic and lifestyle factors In addition to these physiological mechanisms, genetic and environmental factors play a significant role in the development of hypertension, including lifestyle influences such as diet, physical activity, electrolyte imbalance and obesity. Conclusion Overall, hypertension is a multifactorial condition that arises from the interaction of vascular, renal and hormonal systems, influenced by both genetic predisposition and environmental factors. These interconnected processes create a cycle that sustains and progressively worsens elevated blood pressure over time, highlighting the complexity of its pathophysiology. Written by Michelle Amoah Related articles: Hypertension / Cardiac regeneration REFERENCES Adua, E. (2022). Decoding the mechanism of hypertension through multiomics profiling. Journal of Human Hypertension, 37(4), 253–264. Beevers, G., Lip, G. Y. H., and O’Brien, E. (2001). The pathophysiology of hypertension. BMJ, 322(7291), 912.1-916. Hayat, M. A. (2015). Introduction to Autophagy. In Autophagy: Cancer, Other Pathologies, Inflammation, Immunity, Infection, and Aging (pp. 1–53). Elsevier. Klabunde, R.E. (2024). Centrally Acting Sympatholytics. CV Pharmacology. Available at: https://cvpharmacology.com/vasodilator/central-acting . Accessed 4th July, 2026. Nadar, S. (2015). Pathophysiology of hypertension. In Hypertension (pp. 9–14). Oxford University Press. Nepali, P., Suresh, S., Pikale, G., Jhaveri, S., Avanthika, C.,Bansal, M., Islam, R., and Chanpura, A. (2022). Hypertension and the Role of Dietary Fiber. Current Problems in Cardiology, 47(7), 101203. Sahay, M., and Sahay, R. (2012). Low renin hypertension. Indian Journal of Endocrinology and Metabolism, 16(5), 728. Project Gallery

'Manis pentadactyla' is the dominant pangolin species in China Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Pangolins: from poached to protected Last updated: 27/03/25, 11:15 Published: 27/02/25, 08:00 'Manis pentadactyla' is the dominant pangolin species in China This is article no. 4 in a series on animal conservation. Next article: How Gorongosa National Park went from conflict to community . Previous article: Beavers are back in Britain Pangolins are a group of eight scaled mammal species from Asia and Africa. They are being poached mainly for their scales and meat, driving them to dangerously low numbers. Although commercial trade is banned for all species, pangolins are the most illegally trafficked animals in the world. One pangolin species has a fascinating story because of its appeal to traditional medicine and demand in a populated country. That species is the Chinese pangolin Manis pentadactyla , and this article will describe its threats and conservation efforts. About pangolins in China Manis pentadactyla is the dominant pangolin species in China, living south of the Yangtze River ( Figure 1 ). The Sunda pangolin Manis javanica has a tiny habitat in southwest China ( Figure 1 ). Pangolins prefer natural forests, with an ambient temperature of 18-27°C and plenty of termites and ants to eat. Both Chinese species were classified as critically endangered in 2014, though accurately estimating pangolins' distribution and population size is complex. This is because they are nocturnal, solitary, and live underground. Pangolins also make no obvious sounds, or leave no apparent traces, for scientists to detect their presence. Despite these challenges, Chinese scientists are learning more about pangolin habitat to improve conservation strategies. Threats facing Chinese pangolins Chinese pangolins are critically endangered for various human-caused reasons ( Figure 2 ). The biggest reason is poaching because pangolin meat is a local delicacy, and its scales, bones, and blood are used in traditional Chinese medicine. Pangolin scales have recently been removed from the official list of ingredients for Chinese medicine, but that has not stopped hospitals from selling them. In a recent study, only a third of Chinese hospitals selling roasted pangolin scales had the required permit. Permits are also needed to sell or manufacture patented medicines containing pangolin scales, considered the gold standard for treating many conditions. Because these medicines and pangolin meat are so revered, one hunted pangolin sells for up to 90,000 yuan (≈£9800). This has incentivised the hunting and illegal trafficking of non-native pangolin species into China - where they could outcompete, or spread diseases to native species. Thus, illicit trade for traditional medicine threatens Chinese pangolins. Habitat destruction has made Chinese pangolins more vulnerable to poaching. Natural forests are being destroyed to grow crops, grow economic trees like rubber, or build human infrastructure. Farms or rubber plantations have fewer ants and termites than natural forests, so pangolins cannot survive there. As a result, in some parts of China, the pangolin geographical range halved in 30 years. With acres of this unsuitable habitat separating fragments of forest, pangolins may struggle to find mates, and inbreeding could be an issue. Thus, habitat loss is contributing to the decline of the Chinese pangolin. Conservation Conservation measures were taken in the last few decades in response to the pangolin population decline. In China, hunting pangolins was first restricted in 1987, and they were given legal protection in 1989. The Chinese government tightened this protection in 2020 after suggestions that pangolins were an intermediate species for SARS-CoV-2 to transmit from bats to humans. In addition to national restrictions, international authorities restricted pangolin trade, and the Chinese government ran public awareness campaigns about their endangered status ( Figure 3 ). Pangolins also have 100,000 squared kilometres of protected habitat in China, though this is only 9% of what models predict as a suitable pangolin habitat. Habitat protection and trade restrictions are essential to protect pangolins because captive breeding has either failed or acted as a front for illegal trafficking. Although Chinese pangolin conservation has come far in the last 40 years, more can be done. Conclusion Humans have driven Chinese pangolins to near extinction, mainly by hunting for traditional medicine ingredients and destroying native habitats. Conservation efforts have primarily involved legal and habitat protection, but pangolins are challenging to monitor and impossible to breed in captivity. Hopefully, public awareness and a clampdown on illegal trafficking will help to save this unique mammal species. Written by Simran Patel Related articles: Conservation of marine iguanas / Galapagos tortoises REFERENCES Challender, D. et al. (2013) IUCN Red List of Threatened Species: Manis pentadactyla . IUCN Red List of Threatened Species . Available from: https://www.iucnredlist.org/en (Accessed 23rd October 2024). Convention On International Trade In Endangered Species Of Wild Fauna And Flora (2017) Appendices I, II and III valid from 4 October 2017 . Available from: https://cites.org/sites/default/files/eng/app/2017/E-Appendices-2017-10-04.pdf . Mammoser, G. (20th February 2017) Chinese Police Go After ‘Pangolin Princess’ Who Proudly Eats Endangered Species. VICE . Available from: https://www.vice.com/en/article/chinese-police-go-after-pangolin-princess-who-proudly-eats-endangered-species/ (Accessed 23rd October 2024). Wang, Y., Turvey, S.T. & Leader-Williams, N. (2023) The scale of the problem: understanding the demand for medicinal pangolin products in China. Nature Conservation . 52: 47–61. Available from: https://doi.org/10.3897/natureconservation.52.95916 (Accessed 23rd October 2024). Xinhua News Agency (2015) Opinions of the Central Committee of the Communist Party of China and the State Council on Accelerating the Construction of Ecological Civilization . Beijing: The Central Government of the People’s Republic of China. Available from: https://www.gov.cn/xinwen/2015-05/05/content_2857363.htm (Accessed 23rd October 2024). Zhang, F., Chen, Y., Tang, X., Xi, F., Cen, P., Pan, Z., Ye, W. & Wu, S. (2024) Predicting the distribution and characteristics of Chinese pangolin habitat in China: Implications for conservation. Global Ecology and Conservation . 51: e02907. Available from: https://www.sciencedirect.com/science/article/pii/S2351989424001112 (Accessed 23rd October 2024). Zhang, F., Wang, W., Mahmood, A., Wu, S., Li, J. & Xu, N. (2021) Observations of Chinese pangolins ( Manis pentadactyla ) in mainland China. Global Ecology and Conservation . 26: e01460. Available from: https://www.sciencedirect.com/science/article/pii/S235198942100010X (Accessed 23rd October 2024). Zhang, F., Wu, S. & Cen, P. (2022) The past, present and future of the pangolin in Mainland China. Global Ecology and Conservation . 33: e01995. Available from: https://www.sciencedirect.com/science/article/pii/S235198942100545X (Accessed 19th October 2024). Project Gallery

The web of geopolitics surrounding the Rohingyas, and how this impacts their health Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Addressing the health landscape of Bangladesh’s Rohingya community Last updated: 05/03/26, 15:04 Published: 18/09/25, 08:00 The web of geopolitics surrounding the Rohingyas, and how this impacts their health This is article no. 6 in a series about global health injustices. Previous article: Health gaps in conflict-affected Kashmir. Next article: A deep, critical reflection . Introduction Welcome to the sixth article of the Global Health Injustices Series, a collaboration with Nasif Mahmood . This article focuses on the ongoing injustices and health issues affecting the Rohingya refugees in Bangladesh. This community leads a vulnerable life and suffering that it is becoming one of the most significant South Asian crises in the 21st century. Due to Bangladesh's inadequate resources and geopolitical situation, the overall health and well-being of the country and the migratory population are severely hampered. A brief history of Bangladesh and the Rohingya population Bangladesh's history is intricate and has been influenced by many cultures. After India was divided in 1947, the area, previously part of ancient Bengal, was ruled by the British and became East Pakistan. Demands for autonomy resulted from tensions between West and East Pakistan. The Bangladesh Liberation War in 1971, culminating in these tensions, led to the country's independence. Bangladesh has made great strides in education, health, and economic growth since gaining its autonomy, despite facing economic hardship, political turmoil, and natural disasters. Rohingya, the Muslim ethnic minority from the state of Rakhine, were denied citizenship by the Myanmar Government, leaving them homeless. They endured years of persecution, discrimination, and violence. In 2017, an inhuman, violent crackdown by the military of the Myanmar government forced over 70,000 Rohingya to flee to Bangladesh. Over 1 million refugees live in Bangladesh, primarily in the Cox Bazar area. A lot of refugees cause overcrowding situations, and limited resources lead to a high rate of nutritional problems and spread of disease, specifically infectious diseases and mental health disorders in the refugee camp. Connecting geopolitics and health: impacts on the Rohingya population The Rohingya crisis is more than just a humanitarian issue; it is a tangled web of geopolitical challenges. The Myanmar government’s ongoing refusal to grant citizenship and fundamental rights to the Rohingya people not only deepens their suffering but also fuels instability in the region. They have not taken the necessary steps to ensure their safety, leaving the crisis unresolved. As refugees continue to pour into neighbouring countries, tensions have escalated, placing a heavy burden on host nations like Bangladesh. This crisis worsens existing socio-economic problems and stretches resources thin in areas struggling to care for their citizens. The international community has responded in various ways; some countries are pushing for tougher sanctions against Myanmar, while others are focused on delivering aid to those affected. However, the underlying issues driving this crisis will unlikely be resolved without a coordinated and sustained political effort ( Table 1, Figure 1 ). Addressing them can lead to improved outcomes for the Rohinyga population. On top of that, the health challenges faced by the Rohingya people go beyond just infectious diseases. The lack of access to essential health services has not only worsened physical health problems but has also led to a growing mental health crisis. Many Rohingya individuals are grappling with post-traumatic stress disorder (PTSD), anxiety, and depression stemming from their traumatic experiences of violence, loss, trauma, isolation, and forced displacement. Yet, mental health services in the refugee camps are severely lacking. A study showed that the prevalence of emotional and behavioural disorders is high among forcefully migrated refugee children, because of traumatic exposure like the unexpected death of parents, forceful displacement, and the witnessing of family violence and abuse. The stigma surrounding mental health in many cultures, including in the Rohingya community, creates additional hurdles for those seeking help. Enhancing access to mental health support is crucial, not just for the immediate well-being of the refugees, but also for their long-term healing and successful integration into the societies that host them. Moreover, providing humanitarian aid and hosting such a large population in Bangladesh is becoming difficult. The national and international NGOs maintain healthcare for the Rohingya population. However, the funding shortage and inadequate infrastructure hinder the provision of adequate medical services. For this reason, the refugee camps have reported significant outbreaks of diphtheria, cholera, and COVID-19. Given the challenges, developing innovative solutions and working collaboratively on a global or regional scale is needed. By empowering local health workers and training them to offer basic healthcare and mental health support, to close the service delivery gaps. Additionally, building partnerships among NGOs, governments, and international organisations can help ensure that resources are allocated more effectively and that comprehensive health programs are created to meet the unique needs of the Rohingya population. It's crucial to engage the community; by listening to the voices and experiences of the Rohingya, we can develop interventions that truly respect their dignity and cultural context. Additionally, raising global awareness about the struggles faced by the Rohingya can lead to stronger advocacy efforts. Involving the media, educational institutions, and civil society can foster a deeper understanding of the interconnected issues of geopolitics and health. Initiatives that share personal stories and experiences can rally public support and drive meaningful change. Ultimately, tackling the Rohingya crisis calls for a multifaceted approach that blends immediate humanitarian aid with long-term strategies aimed at ending their statelessness and ensuring their rights as human beings are upheld and protected. Recommendations from NGOs National NGOs: Several national NGOs play an essential role in supporting the healthcare needs of the Rohingya population: Bangladesh Rural Advancement Committee (BRAC), one of the world's largest NGOs, provides comprehensive health care services, including maternal and child health, immunisation programmes, disease prevention initiatives, and arranges many health campaigns for refugees. Gonoshasthaya Kendra established a field hospital and free clinic in the Cox Bazar area near the refugee camp, focusing on primary health care and emergency medical support. International NGOs MedGlobal, an international NGO, responds to this global crisis by delivering medical assistance within the refugee camp. Support hospitals and clinics for affected refugees between 2017 and 2019. This organisation's volunteers contributed over 17,000 hours of aid, assisting more than 80,000 individuals. Medair is another international NGO offering health and nutritional support to the Rohingya refugees. Migrant Offshore Aid focuses on sea rescue operations and delivering medical aid and assistance to surfers. Together, these national and international organisations make meaningful contributions to the healthcare needs of the Rohingya population, handling both immediate medical concerns and long-term health support in a challenging environment. Their collaborative efforts help ensure that essential services reach those in critical need, facilitating better health outcomes for refugees. Although they address the healthcare needs of the Rohingya, several challenges can limit their effectiveness. For example, coordination issues may lead to overlapping efforts or service gaps, resulting in inequitable and unequal healthcare access. Also, limited resources and funding can slow extensive long-term support, leaving specific medical needs unaddressed. Additionally, the intricate political and social conditions restrict these organisations' capacity to operate effectively, impacting immediate care and sustainable health initiatives for the Rohingya population. Moving forward, it is crucial for host countries to: finance extra healthcare facilities in refugee camps to enhance access and reduce diseases, launch culturally appropriate mental health initiatives with locally trained workers to decrease stigma and provide community-based support, integrate nutrition programmes to address different forms of malnutrition in vulnerable communities and encourage further international support to maintain health initiatives among the Rohingya population. Conclusion The Rohingya crisis is an example of global health injustice exacerbated by geopolitical and humanitarian challenges. At the same time, Bangladesh is trying to provide temporary shelter for the refugees to minimise the crisis. However, this crisis also requires international cooperation, policy support, and increased funding. Solving this issue is essential for global public health and human rights. Notably, finding sustainable solutions will help the Rohingya people recover and thrive, and enhance stability and security in the region. Their future goes beyond humanitarian aid; it is about upholding inclusion, justice, and respect for human dignity, which should guide all efforts to link geopolitics with health outcomes. To truly tackle the health issues faced by the Rohingya community, we need to take a comprehensive approach that looks at the political, social, and economic factors at play. By adopting such all-encompassing systems, we can work towards a brighter and fairer future for the Rohingya community and other vulnerable groups around the globe who are facing similar challenges. The next article will be the final one reflecting on everything discussed in this series. Written by Nasif Mahmood and Sam Jarada Related articles: Health and well-being in- Palestine , Kashmir / South Asian famine / South Asian mental health / Ethnic health inequalities REFERENCES Tinker HR. History of Bangladesh | Events, People, Dates, & Facts [Internet]. Encyclopedia Britannica. 2023 [cited 2025 Jul 15]. Available from: https://www.britannica.com/topic/history-of-Bangladesh Rahman MM, Bhuiyan MR, Ali MZ, Rahman MS, Hossain MA. Insecurity feelings and mental health status of Rohingya orphan children in BangladeshResearchGate; 2021 https://www.researchgate.net/publication/348521935_Insecurity_Feelings_and_Mental_Health_Status_of_Rohingya_Orphan_Children_in_Bangladesh UNHCR. Rohingya refugee crisis – Bangladesh. 2023. https://www.unhcr.org International Crisis Group (ICG). The health crisis in Rohingya refugee camps. 2022. https://www.crisisgroup.org Tay AK, Riley A, Islam R, Welton-Mitchell C, Duchesne B, Waters V, et al. The culture, mental health and psychosocial wellbeing of Rohingya refugees: a systematic review. Epidemiology and Psychiatric Sciences [Internet]. 2019 Apr 22 [cited 2025 Sep 10];28(5):489–94. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC6998923/ Human Rights Watch. The plight of Rohingya refugees in Bangladesh. 2023. https://www.hrw.org . Nivedita Sudheer, Banerjee D. The Rohingya refugees: a conceptual framework of their psychosocial adversities, cultural idioms of distress and social suffering. Cambridge Prisms Global Mental Health [Internet]. 2021 Jan 1 [cited 2025 Sep 10];8. Available from: https://www.cambridge.org/core/journals/global-mental-health/article/rohingya-refugees-a-conceptual-framework-of-their-psychosocial-adversities-cultural-idioms-of-distress-and-social-suffering/F4D229807D4ED7667EA16195FDF5C787 World Health Organization (WHO). Health challenges in Rohingya refugee camps. 2022. https://www.who.int Médecins Sans Frontières (MSF). Medical response in Rohingya refugee settlements. 2022. https://www.msf.org Project Gallery

This requires a strategy accounting for different factors, as well as other wider determinants of health Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Addressing Health Inequalities Last updated: 03/05/26, 18:09 Published: 02/04/26, 08:00 This requires a strategy accounting for different factors, as well as other wider determinants of health This is the fourth and final article in a series on health inequalities. Previous article: Ethnic health equalities. Welcome to the final article in a series of articles about health inequalities. This article will look more in detail at how to address health inequalities. Introduction Health inequalities are systematic and avoidable differences in health outcomes. They carry heavy human and economic costs, including over £31bn in lost productivity annually. Previous articles in this series explored how factors like geography, income, and ethnicity drive these disparities. However, addressing healthcare inequalities requires a strategy accounting for these factors, as well as other wider determinants of health. The impact of the environment Scientists have published research which found that environmental factors, including smoking, physical activity, and socioeconomic status, have a greater impact on a person’s health and premature death compared to their genes. They analysed data from the UK Biobank, a dataset of biological, health and lifestyle information. Their analysis showed that environmental exposure explains 17% of the variation in risk of death, while genetic predisposition explains less than 2%. Of the 25 factors that were analysed, smoking was linked to 21 diseases, followed by 19 diseases for socioeconomic factors like household income, home ownership, and employment status. While genetics still dominates for specific conditions like dementia and breast cancer, these findings emphasise that the vast majority of health outcomes are determined by our environment rather than our biology. Therefore, to address health inequalities, targeted strategies and collaborative methods like co-design need to be used to ensure interventions meet the genuine needs of the most vulnerable communities. Core20PLUS5 The NHS’s Core20PLUS5 is one of these targeted strategies, defining a target population (the “Core20PLUS”) and identifying 5 areas of healthcare that require improvement. For both groups (adults, children and young people), the target population is the same: CORE20 refers to the most deprived 20% of the population identified by the national Index of Multiple Deprivation, while the PLUS population includes those who experience health inequalities the most, such as ethnic minority groups, individuals with a learning disability, autistic individuals, and individuals with multiple long-term health conditions. The differences between the strategy for adults and that for children and young people are in the 5 areas of healthcare requiring improvement. As seen in Figure 1 , for adults, the 5 areas are continuity and improvement of maternity care (specifically for women from Black, Asian and ethnic minority groups and from the most deprived groups), improved services for individuals with severe mental illness, improved services for those with chronic respiratory disease, early cancer diagnosis, and improved management of hypertension. Smoking cessation is another area of focus that covers all the 5 priorities. For children and young people, the 5 areas of healthcare improvement are specific to this population: asthma care, diabetes care, epilepsy care, oral health, and mental health, as seen in Figure 2 . Co-design for addressing health inequalities Another method to address health inequalities is through co-design, which is a participatory methodology where stakeholders, including service users (e.g., patients, their carers, etc) and providers (healthcare professionals and other staff), collaborate to jointly create and refine services, products, or solutions. A diagram of three key factors needed in co-design can be seen in Figure 3 . This joint approach helps to ensure that interventions align with the genuine needs and preferences of the people who will be using that service, and the findings that providers see coming up frequently from comments by service users. Co-design can be used to address health inequalities by co-producing strategies with people from those communities and backgrounds. For example, individuals from ethnic minority groups can participate, so researchers can genuinely understand and try to address racism's impact on health. This is supported by research published in the BMJ , where co-design with service users and providers from ethnic minority groups found that more culturally appropriate mental healthcare was needed, and that there needed to be more open discussions about the impacts of ethnicity, culture and racism in mental health. In the context of Figure 3 , this study involved “committed” ethnic minority groups with the “capability” of sharing their lived experience with researchers. This shows how co-design can be used as a tool that allows others to share their experiences for the benefit of themselves and others. Conclusion There needs to be a cross-government strategy that aligns current policy, funding, and practice around health equity. Because these inequalities are systematic and avoidable failures, they require a holistic approach that moves beyond clinical care to address the PLUS populations who experience the greatest disadvantage. Trust in the healthcare system has been eroded among ethnic minority groups due to repeated negative experiences, cultural insensitivity, and discriminatory treatment. To rebuild it, lived experiences need to be accounted for, and solutions need to be co-designed. Furthermore, determinants of good health, like stable housing, fair pay, and high-quality education, must be provided to the people most affected by health inequalities. These inequalities must be addressed to ensure everyone has the ability and opportunity to have a long and healthy life. Written by Naoshin Haque Related article: Reflection on global health injustices Project Gallery

About phosphate-solubilising micro-organisms and their role in the phosphorus cycle Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Meet the microbes that feed phosphorus to plants Last updated: 15/01/26, 19:00 Published: 27/11/25, 08:00 About phosphate-solubilising micro-organisms and their role in the phosphorus cycle Plants need phosphorus to make biological molecules like DNA, ATP, and the phospholipid bilayers that form cell membranes. Most phosphorus on Earth is found in its most oxidised form, phosphate (PO 4 3- ). Plant roots can only absorb soluble phosphate ions, but 80% of the phosphate in soil is insoluble and therefore unavailable for plant growth. Enter phosphate-solubilising micro-organisms. What are phosphate-solubilising micro-organisms? Phosphate solubilisation is the process by which micro-organisms convert insoluble phosphorus sources, like rocks or the biomass of dead organisms, into bioavailable phosphate ions (Figure 1). Examples of phosphate-solubilising bacteria come from the genera Bacillus , Pseudomonas , Rhizobium, Escherichia , Streptomyces , and Micromonospora , as well as some cyanobacteria. Phosphate-solubilising fungi include Aspergillus , Penicillium , Mucor , Rhizopus , Rhizophagus, and Glomus . The latter two fungal genera are arbuscular mycorrhizal (AM) fungi - more on them later. The chemistry underpinning phosphate solubilisation is complex but can broadly be split into inorganic and organic processes ( Figure 1 ). Some of these inorganic and organic processes are described in the rest of this article. Solubilising inorganic phosphate Inorganic insoluble phosphate is solubilised by microbial acids. When phosphate-containing rocks like apatite are broken down by weathering, the resulting smaller rock particles enter the soil. Micro-organisms secrete organic acids – usually gluconic acid but occasionally lactic, citric, oxalic, or other acids – to solubilise these rock particles. Acids work on inorganic phosphate in two ways. Firstly, they dissolve weathered rock pieces due to their low pH. Secondly, negatively charged acid anions (lactate, citrate, etc) displace the phosphate captured by aluminium, iron, magnesium, and calcium minerals in the rock. Organic acids are just some of the chemicals secreted by microbes to solubilise inorganic phosphate. Solubilising organic phosphorus On the other hand, microbial enzymes solubilise organic phosphorus during the decomposition of organic matter. The two types of phosphate-solubilising enzymes are phosphatases, which solubilise 90% of organic phosphorus, and phytases, which solubilise the remaining 10%. Both types of enzyme break the ester bonds linking a PO 4 3- group to the rest of a biological molecule. By expressing genes encoding phytases and phosphatases, soil micro-organisms make phosphorus available for plants. Arbuscular mycorrhizae (AM) AM fungi provide plants with phosphorus in a symbiotic relationship. These fungi consist of hyphae, which are long, thin strands of cells that extend a plant’s root network and access phosphorus where roots cannot (Figure 2). AM fungi have a three-pronged approach to improving a plant’s phosphorus uptake: firstly, they absorb phosphate from the soil and give it to the plant in exchange for carbon. Secondly, they solubilise phosphate by secreting acids and phosphatases. Finally, AM fungi recruit phosphate-solubilising bacteria to the root system by feeding them sugars and amino acids. Conclusion Phosphate-solubilising bacteria and fungi provide plants with phosphorus, an essential element for making nucleic acids and ATP. Most phosphate is inaccessible to plants, locked up in rocks and biomass. By secreting organic acids and enzymes, soil micro-organisms convert this inaccessible phosphate into a form that plant roots can absorb and incorporate into their own biomass. When that plant dies, the organic phosphorus is solubilised again for another plant to use, so phosphorus never runs out. Therefore, phosphate-solubilising microbes are a small part of the invisible world that keeps our planet green. Written by Simran Patel Related article: Human activity and the phosphorus cycle REFERENCES Silva LI da, Pereira MC, Carvalho AMX de, et al. Phosphorus-Solubilizing Microorganisms: A Key to Sustainable Agriculture. Agriculture 2023; 13: 462. Pang F, Li Q, Solanki MK, et al. Soil Phosphorus Transformation and Plant Uptake Driven by Phosphate-solubilizing Microorganisms. Front Microbiol ; 15. Epub ahead of print 27 March 2024. DOI: 10.3389/fmicb.2024.1383813 . Schipanski ME, Bennett EM. Chapter 9 - The Phosphorus Cycle. In: Weathers KC, Strayer DL, Likens GE (eds) Fundamentals of Ecosystem Science (Second Edition) . Academic Press, pp. 189–213. Tian J, Ge F, Zhang D, et al. Roles of Phosphate Solubilizing Microorganisms from Managing Soil Phosphorus Deficiency to Mediating Biogeochemical P Cycle. Biology 2021; 10: 158. Project Gallery

Looking at silicon dioxide Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link The effects of nanoparticles on health Last updated: 17/07/25, 11:50 Published: 01/05/25, 08:00 Looking at silicon dioxide There are around 100 trillion harmless and beneficial microbes in the gut, representing as many as 5,000 different species! They are called the gut microbiota and are essential for regulating brain function through the microbiota-gut-brain axis, controlling intestinal inflammation and more. Nanoparticles may alter the gut microbiota, posing a risk to health and well-being. Read on to find out more about how. What are nanoparticles? Nanoparticles are small particles that are usually less than 100 nm in diameter. One example of a common nanoparticle is silicon dioxide, which can be found as the food additive E551. Silicon dioxide nanoparticles (SiO2NPs) are commonly used as anti-caking agents in free-flowing powdery food products, such as spices and coffee. These nanoparticles can be toxic, damaging cells, tissues, and organs including the liver, kidneys, and lungs. The damage is primarily due to the way SiO2NPs react in the body as a result of their size: even though SiO2NPs are bigger than 100 nm in the form of E551, when the SiO2NPs are in the gastrointestinal tract, they can clump together and degrade into a smaller size of 10-50 nm. The experiment Researchers completed several experiments to examine the effects of exposure to SiO2NPs on health. This article will specifically talk about one experiment where they looked at the impacts of SiO2NPs on the gut microbiota. For this experiment, the researchers hypothesised that oral exposure to SiO2NPs will cause changes in the gut microbiota, affecting diversity and function in mice. 20 healthy male 4-week-old mice were used, weighing 8 to 12 grams. Researchers administered either SiO2NPs solution or vehicle solution for 28 days. The vehicle solution can be considered the control and was created out of a sterile saline solution. All bacteria contain the 16S rRNA gene which is highly conserved, meaning that the sequence remains mostly unchanged across different species. After 28 days, the researchers took faecal samples from the mice and conducted 16S rRNA gene sequencing of the bacterial DNA in the faeces to analyse the gut microbiota. Figure 1 shows the process of 16S rRNA gene sequencing, a method used to identify and compare bacterial diversity without needing to grow bacterial cultures. Because it is culture-free, 16S sequencing can survey complex microbiomes or difficult environments to study. This technique is commonly used to identify bacteria down to the genus or species level, depending on the needs of the experiments. Researchers looked at the alpha diversity of the gut microbiota, with Sob, Ace, Chao, Simpson, and Shannon indices being used. Sob, Ace and Chao give information about the number of species, while Simpson and Shannon give information about the community diversity, including the species evenness. The results The results of this experiment, as seen in Figure 2 , show that there was a significant increase in Sob, Ace, and Chao indices, but there was no substantial change in Simpson or Shannon indices. This suggests that SiO2NPs can change the diversity of gut microbiota, which could impact their biological functions. For example, if there are changes to the gut microbiota, it could result in increased inflammation in the intestine. This could potentially lead to the immune system’s defences in the gut being weaker, allowing harmful pathogens to pass through the epithelial barrier more easily. Conclusion One of the main weaknesses of this experiment is that it was conducted on mice. Because of this, the study's findings cannot be directly translated to humans. In addition, the study was conducted over only 28 days, meaning we don’t know the long-term effects and consequences of the impacts of SiO2NPs on the gut microbiota. Nevertheless, this is still a critical study as it shows that SiO2NPs do impact the gut microbiota. It also shows that maintaining healthy gut microbiota is important. This can be done by being mindful of what we eat. So next time, instead of having instant noodles full of additives, think about making a home-made soup with your favourite vegetables! Eating unprocessed whole foods is not just good for us, but also for our gut microbiota! Written by Naoshin Haque Related articles: Nanomedicine / Nanoparticles as diabetes treatment / Nanogels / Nanocarriers / Silicon hydrogel lenses / Microbiota Project Gallery

Health inequalities and inequities amid the ongoing civil war Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Healthcare challenges during civil war in Sudan Last updated: 03/05/26, 18:15 Published: 17/04/25, 08:00 Health inequalities and inequities amid the ongoing civil war This is article no. 2 in a series about global health injustices. Next article: Yemen: a neglected humanitarian crisis . Previous article: Life under occupation in Palestine Introduction Welcome to the second article of the Global Health Injustices Series. My previous article focused on the Palestinians and the injustices they face, notably the blockade of food, water and medical supplies in Gaza. This one will focus on Sudan by examining the health inequalities and inequities the wider Sudanese population faces, mainly due to the ongoing civil war between the Sudanese Armed Forces (SAF) and the Rapid Support Forces (RSF). This carries direct and indirect consequences ( Figure 1 ); some of these will be discussed in this article, along with ways forward to advocate and support the Sudanese people after an overview of Sudan’s history and current state. Sudan: a rich history to modern challenges Sudan is a country in North Africa bordered by South Sudan, Egypt, the Central African Republic, Libya, Chad to the northwest, Eritrea and Ethiopia. Sudan has had shifts in political power over centuries, notably the joint Egyptian-Ottoman rule beginning over 200 years ago, before the British government took control of Sudan during the first half of the 20th century. After that, Sudan became independent, and South Sudan gained independence in the 21st century. Through these different shifts, there has been a struggle for representation and power in Sudan, leading to various crises, including the current civil war ( Figure 2 ). Despite this, Sudan maintains its multiple languages and cultural traditions through its resilient population. Aside from the SAF and RSF, the civil war in Sudan has arms trade and exports from external governments, particularly the United Arab Emirates (UAE), Russia, and China, have accelerated the civil war. This expansion is crucial because it illustrates how much geopolitics has severe consequences on the health and wellbeing of the Sudanese people. Health in Sudan: the consequences of civil war and geopolitics In a public health situation analysis (PHSA) by the World Health Organisation (WHO) published in 2026, they highlighted four major emergencies in Sudan: food insecurity, displacement, epidemics and conflicts, which are intrinsically linked to detrimental health outcomes like non-communicable diseases (NCDs), trauma and injury, measles and malaria. Moreover, several mortality indicators were noted in the PHSA. For example, the mortality rate among infants is 39.1 per 1000 people and for children, it is 50.1 per 1000, both originating from the United Nations Children's Fund (UNICEF). These outcomes among infants and children are attributed to health conditions, such as those occurring neonatally and lower respiratory infections. Nonetheless, there has been increased vaccine coverage in Sudan to fight the spread of infectious diseases. For example, COVID-19 vaccination reached approximately 12.6 million people (28% of the population) in March 2023, along with improved polio and rotavirus vaccination. However, all of these outcomes highlight the magnitude of the civil war in Sudan, with the impact of the arms trade adding fuel to it. Looking at Sudan’s healthcare system, there are several pressures to highlight. One commentary article noted that in conflict areas, less than one third of hospitals are operational, while 70% of them are not. Additionally, the operating hospitals stopped for various reasons, mainly shortages in electricity, medical equipment and healthcare workers. With the aforementioned geopolitical context, these gaps in the healthcare system are amplified and lead to the worsening health outcomes outlined in the PHSA, such as the rise in NCDs. Not only are NCDs rising in Sudan, but infectious diseases are exacerbated in Sudan with the civil war. One of them is drug-resistant tuberculosis (DR-TB), caused by bacteria. One systematic review found that the prevalence of TB with resistance to drugs was 47%; the ones that are not working on TB with the highest resistance include isoniazid at 32.3%, streptomycin at 31.7% and rifampicin at 29.2% resistance. These values are likely to be higher nowadays, given that arms trade exports into Sudan are increasing and leading to more patients not getting sufficient care to manage or treat DR-TB. Another infectious disease that is a significant health problem in Sudan is schistosomiasis, which is caused by parasites. One systematic review included two categories of the disease: Schistosoma haematobium (S. haematobium) and Schistosoma mansoni (S. mansoni) . S. haematobium prevalence was 24.83%, and for S. mansoni , it was 19.13%. These signify that although devising preventative strategies against these infections is crucial, it is paramount to consider the broader picture in Sudan: tackling schistosomiasis and other infections begins with understanding the geopolitical context. Looking at undernutrition among children in Sudan it is another significant health problem. For instance, a meta-analysis found that Sudan had the highest prevalence of stunting among North African countries at 36%; this was also true for wasting, where Sudan had a prevalence of wasting at 14.1% and a prevalence of underweight at 24.6%. Therefore, in a similar sentiment to tackling infectious diseases, understanding the geopolitical context in Sudan is vital to minimising the prevalence of undernutrition among children. Reflecting on all the data and sources I used above, gaps and perspectives still need to be addressed and highlighted, specifically in places within Sudan where the ongoing civil war severely impacts research. This signifies the importance of obtaining reliable information to support communities in Sudan facing numerous injustices. In turn, filling these information and perspective gaps may apply to other crises similar to Sudan. Protecting health in Sudan: crucial ways forward from NGOs To move forward, several NGOs, particularly Amnesty International, have made recommendations to protect the Sudanese people: As a part of their obligation to respect and ensure respect for international humanitarian law (IHL), all states are prohibited from transferring or permitting private actors to transfer weapons to a party to an armed conflict In light of the substantial risk that all arms and ammunition being transferred to Sudan….. will be used by parties to the conflict to commit grave human rights abuses, companies must immediately cease their involvement in this supply of arms to avoid causing or contributing to these abuses. If a company identifies that the products they sold have contributed to such abuses, they should provide for or cooperate in the remediation process to any persons harmed as a result. Therefore, taking these steps on board is essential to upholding human rights and ensuring that the health and wellbeing of the Sudanese people are sustained, particularly during the ongoing civil war. If not, these health inequities and inequalities will only be exacerbated. Moreover, the health outcomes from infectious and chronic diseases outlined are likely worse now, given how much weapons trading has occurred. Conclusion: call to action for the international community Overall, the civil war in Sudan has had devastating impacts on the health and wellbeing of the whole population, particularly the infants and children, among the other injustices. Unfortunately, this crisis has not received a lot of mainstream attention compared to others currently, such as Palestine, which is also a significant injustice. Therefore, Sudan must be addressed just as openly through discussions of justice and advocacy through the voices of the Sudanese people. Moreover, my statement in the previous article on Palestine rings true: 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. This is essential to maintain the health and wellbeing of the Sudanese people, particularly to facilitate the recommendations from NGOs such as Amnesty International. In my next article, I will discuss Yemen because this population is also encountering civil war as one of the many injustices which have been occurring for more than a decade, and Yemen is considered to be going through one of the worst humanitarian crises of our time. Similarly, these impacts on the health and wellbeing of the Yemeni people still need awareness and discussion. Written by Sam Jarada Related articles: A perspective on well-being / Understanding health through different stances / Impacts of global warming on dengue fever REFERENCES Crisis in Sudan: What is happening and how to help. The IRC. 2025. Available from: https://www.rescue.org/article/crisis-sudan-what-happening-and-how-help Khogali A, Homeida A. Impact of the 2023 armed conflict on Sudan’s healthcare system. Public Health Challenges. 2023 Oct 28;2(4). Available from: https://onlinelibrary.wiley.com/doi/full/10.1002/puh2.134 Elamin A, Abdullah S, ElAbbadi A, Abdellah A, Hakim A, Wagiallah N, et al. Sudan: from a forgotten war to an abandoned healthcare system. BMJ Global Health. 2024 Oct;9(10):e016406. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC11529772/ New weapons fuelling the Sudan conflict. Amnesty International. 2024. Available from: https://www.amnesty.org/en/latest/research/2024/07/new-weapons-fuelling-the-sudan-conflict/#:~:text=Shipment%2Dlevel%20trade%20data%20indicates,into%20lethal%20weapons%20in%20Sudan . PHSA -Sudan Complex Emergency 030424 SUDAN CONFLICT. World Health Organisation (WHO); 2024. Available from: https://cdn.who.int/media/docs/default-source/documents/emergencies/phsa--sudan-complex-emergency-030424.pdf?sfvrsn=81039842_1&download=true Alaa Dafallah, Osman, Ibrahim ME, Elsheikh RE, Blanchet K. Destruction, disruption and disaster: Sudan’s health system amidst armed conflict. Conflict and Health. 2023 Sep 27;17(1). Available from: https://conflictandhealth.biomedcentral.com/articles/10.1186/s13031-023-00542-9 Hajissa, K., Marzan, M., Idriss, M.I. and Islam, M.A. (2021). Prevalence of Drug-Resistant Tuberculosis in Sudan: A Systematic Review and Meta-Analysis. Antibiotics, 10(8), p.932. doi: https://doi.org/10.3390/antibiotics10080932 . Yousef Alsaafin, Omer, A., Osama Felemban, Sarra Modawi, Ibrahim, M., Mohammed, A., Ammar Elfaki, Abushara, A. and SalahEldin, M.A. (2024). Prevalence and Risk Factors of Schistosomiasis in Sudan: A Systematic Review and Meta-Analysis. Cureus. doi: https://doi.org/10.7759/cureus.73966 . Nagwa Farag Elmighrabi, Catharine, Dhami, M.V., Elmabsout, A.A. and Agho, K.E. (2023). A systematic review and meta-analysis of the prevalence of childhood undernutrition in North Africa. PLoS ONE, 18(4), pp.e0283685–e0283685. doi: https://doi.org/10.1371/journal.pone.0283685 . Project Gallery

Simplifying light: photons, wave-particle duality and the Observer Effect Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Light: one of the biggest mysteries in physics Last updated: 20/10/25, 15:28 Published: 23/10/25, 08:00 Simplifying light: photons, wave-particle duality and the Observer Effect Light is one of those few topics where physicists have to say, ‘We don’t yet know why it is the way it is, we just know that it is that way.’ Let’s start simple. Question 1: What is light? When we think of light, we automatically think of visible light- what we can see with our eyes. But that is only 0.0035% of the total light, or electromagnetic, spectrum. The rest of the spectrum includes non-visible light, such as infrared radiation (what we feel as heat), x-rays (what the medical field’s X-ray machine uses to capture images of bones) or ultraviolet radiation (what causes sunburn). Every kind of light is made up of photons. They are tiny little pockets of energy that travel across space at 3 x 10 8 meters/second at different wavelengths and frequencies. Imagine someone tosses you a tennis ball, but instead of it travelling straight towards you, it oscillates up and down in a wave pattern as it travels. If you take a measurement from peak to peak, this distance is called a wavelength. The tennis ball can move up and down in the wave pattern at different speeds. This speed is called the frequency. Photons can travel at different wavelengths and different frequencies depending on where it originated. The unique wavelength and frequency pair of each photon determines what kind of light it is- where it falls on the electromagnetic spectrum. For example, photons with much shorter wavelengths and therefore much higher frequencies fall towards the right-hand side of the spectrum and are likely gamma-rays or x-rays. On the other hand, photons with much longer wavelengths and much lower frequencies are on the left-hand side, meaning the photons are probably radio waves or microwaves. So far, so good. All of this makes sense, and physicists are fairly confident in this information. So, what’s the problem? Question 2: Why is light so problematic? The trouble with light is its behaviour. Remember those little pockets of energy that move up and down in a wave pattern? Well, that’s not exactly what happens. Light has a property that physicists call ‘wave-particle duality’, which is a fancy term for meaning that sometimes light behaves like a particle (photons) and other times it behaves like a wave. When it behaves as a wave, we get the electromagnetic spectrum. As mentioned above, the wave can have different peak-to-peak lengths and travelling speeds that we read as different types of light across the spectrum. But when the photon behaves as a particle, we get this tiny pocket of energy rocketing across the cosmos. It is the fastest thing in the known universe. To understand the difference a little bit better, imagine you put the tennis ball in one of those pitching machines used for baseball players to practice their swing. It shoots the ball straight out of the front in a direct line and incredibly fast. This is light acting like a photon particle. Now, imagine you and a friend have a rope and each of you are holding on to either end. Your friend starts swinging their end up and down creating waves that travel down the rope towards you. The faster your friend swings their end, the faster the waves travel and the smaller the peak-to-peak distances (wavelengths) of the waves get, and vice versa if your friend slowly swings their end. This is light acting like a wave. The tricky bit is that physicists don’t know why the same pocket of energy can act like a photon particle in one instance, yet like a wave in another! The famous Double-Slit Experiment performed by Thomas Young in 1801 demonstrated this behaviour. Since then, the physics sub-field of quantum mechanics has developed and physicists now think that this behaviour is because of what they call the ‘Observer Effect’, which means that particles behave differently depending on whether or not they are observed. How does the particle know when it is being observed? Well, that is still a mystery to all. Written by Amber Elinsky Related articles: Laser Interferometric Gravitational-wave Observatory (LIGO) / Dark Energy Spectroscopic Instrument (DESI) REFERENCES Wavelength/Frequency Image ref: BYJU’s educational tech company Electromagnetic Image ref: Space.com Baclawski, Kenneth. (2018). The Observer Effect. 83-89. 10.1109/COGSIMA.2018.8423983. Project Gallery