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A new theory suggests intelligence develops through reciprocal interactions between abilities Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link A primer on the Mutualism theory of general intelligence 11/12/25, 14:15 Last updated: Published: 10/10/24, 14:19 A new theory suggests intelligence develops through reciprocal interactions between abilities Introduction One of the most replicated findings in psychology is that if a sufficiently large and diverse battery of cognitive tests is administered to a representative sample of people, an all-positive correlation matrix will be produced. For a century, psychometricians have explained this occurrence by proposing the existence of g, a latent biological variable that links all abilities. G is statistically represented by the first factor derived from a correlation matrix using a method called factor analysis, which reduces the dimensionality of data into clusters of covariance between tests called factors. Early critics of g pointed out that nothing about the statistical g-factor required the existence of a real biological factor and that the overlap of uncorrelated mental processes sampled by subtests was sufficient. While the strength of correlations between subtests does generally correspond to intuitive beliefs about processes shared between them, this is not universally the case, and for this reason, sampling theory has never seen widespread acceptance. A new theory called mutualism has been proposed that explains the positive manifold without positing the existence of g. In mutualism the growth of abilities is coupled, meaning improvement in one domain causes growth in another, inducing correlations between abilities over time. The authors of the introductory paper demonstrated in a simulation that when growth in abilities is coupled the interaction between baseline ability, growth speed and limited developmental resources is sufficient to create a statistical general factor from abilities that are initially uncorrelated, offering a novel explanation for why abilities like vocabulary that are ‘inexpensive’ in terms of developmental resources explain the most variance in other abilities. Empirical evidence In the field of intelligence, mutualism has been tested twice among neurotypical children in the lab and once in a naturalistic setting with data from a gamified maths revision platform. Alongside these, a lone study exists comparing coupling in children with a language disorder and neurotypical children, however methodological issues related to attrition preclude it from discussion here. All studies used latent change score modelling (LCSM) to compare competing models of how intelligence develops over time. LCSM is a subset of structural equation modelling in which researchers compare the discrepancy between models of proposed causal connections between variables and their values in the real data using model fit indices. Three parameters resembling those used in the introductory paper’s simulations were used to represent causal connections between variables: the change score - wave #2 score minus wave #1 score of the same ability, the self-feedback parameter – the regression coefficient of baseline ability on the change score of the same ability and the coupling effect parameter – the regression coefficient of one ability at wave #1 on the change score of the other ability. The following models were compared: the g-factor model defined by the absence of coupling and growth driven by change in the g-factor, the investment model defined by coupling from matrix reasoning to vocabulary and the mutualism model defined by bidirectional coupling. Mutualism in the lab The first two lab studies investigated coupling between vocabulary and matrix reasoning in samples of 14-25 year olds and 6-8 year olds respectively. The mutualism model showed the best model fit in both studies albeit less decisively in the three wave younger sample, suggesting the stronger model fit of the first study may have been an artefact of regression to the mean. I think it’s problematic to interpret this as empirical support for mutualism due to issues that follow from only using two abilities. A g-factor extracted from two abilities may reflect specific non-g variance shared between tests as much as it does common variance caused by g. Adding to this ambiguity is the fact that the correlations between the change scores of the two tests after controlling for coupling and self-feedback effects were positive, reflecting the influence of an unmodelled third variable, be that g or unmeasured coupling. Another problematic feature of the studies comes from their model specification of the g-factor as being without coupling. This is despite the fact no latent change score modelling study of childhood development has ruled out that g may develop in a coupled or partially coupled manner. Studies using the methodology to study cognitive ageing have shown that some abilities are coupled whereas others are not suggesting that only sampling abilities that do show coupling may lead to a biassed comparison. Mutualism in the classroom Mutualism showed a marginally better fit than the investment model in explaining the development of counting, addition, multiplication and division over three years in a study featuring a sample of 12,000 Dutch 6-10 year olds using the revision platform Mathgarden. The change scores of each ability showed strong correlations after controlling for coupling and self-feedback effects. When considered in relation to the good model fit of the investment model, I believe this may reflect the standardised effect of the curriculum on the development of abilities independent of coupling and baseline ability. A finding with negative implications for mutualism from this study is the fact that the number of games played was not associated with any greater strength in coupling. This could reflect that coupling is a passive mechanism of development with little environmental input but it could equally reflect sorting of high ability students into a niche combined with self-feedback effects of their baseline ability impeding coupling. To observe the causal effect of effort on coupling after controlling for cognitive aging and the tendency of high ability people to train harder a randomised control trial of cognitive training is needed. Cognitive training Unfortunately, no cognitive training study has used latent change score modelling, meaning coupling must be inferred from the presence of far transfer (gains on untrained abilities), rather than directly estimated. COGITO’s youth sample resembled the first lab study to test mutualism in its age range and choice of fluid reasoning as a far transfer measure. Participants underwent 100 days of hour-long training sessions of working memory, processing speed and episodic memory. The authors found no near or far transfer gains for working memory and processing speed, possibly indicating developmental limits on their improvement. However, moderate effect sizes were found for fluid reasoning and episodic memory. The study’s results are lacklustre and developmentally bound but they offer an example of experimentally induced far transfer in a literature – in which it is a rarity – leaving open the possibility that the coupling effects observed in the lab studies were not mere passive effects of development. In contrast to COGITO which targeted young people at the tail end of their cognitive development, the Abecedarian Project started almost as soon as the subjects were born. Conceived of as a pre-school intervention to improve the educational outcomes of African Americans in North Carolina, the Abecedarian Project consisted of an experimental group that received regular guided educational play for infants aimed at building early language and a control condition which only received nutritional supplementation. At the entry of primary school, the experimental group showed a 7 point difference in IQ, which persisted in a diminished capacity at 4.4 IQ points by age 21. In contrast to previous early life interventions, in cognitive training studies and studies on the cognitive outcomes of adoption the gains were domain general rather than improvements on specific abilities. This provides causal evidence that if interventions are sufficiently early and target highly g-loaded abilities such as vocabulary they can induce cascades of domain-general improvement, a finding in line with the predictions of mutualism. It would be unfair to end this segment without mentioning perhaps the most standardised cognitive training regime there is: schooling. The causal effect of a year of schooling on IQ can be teased apart from the developmental effects of ageing by using a method called regression discontinuity analysis. In this method, the distance of a student’s birthday from the year cutoff for two year groups is used as a predictor variable alongside the school year in a multiple regression predicting IQ. A recent paper reanalysing data from a study using this method found that the subtest gains from a year of schooling showed a moderate negative correlation with their g loading. As mutualism states that g develops through coupling, this would lend credence to the view that coupling effects are passive mechanisms of g’s development rather than being inseparable from experience. Conclusion I believe that it’s more accurate to say there is evidence for coupling effects than it is to say there is evidence for mutualism. There is convergent evidence from a year of schooling effect, coupling effects not rising with the amount of maths games played and the COGITO intervention’s results that the environment has little causal role in coupling effects and their strength. Opposing evidence comes from the Abecedarian Project, however this is not an environmental stimulus to which most people will be exposed to. Therefore, more weight should be placed on the effects of a year of schooling because it is generalisable. To reconcile this conflicting evidence, future authors should seek to replicate the COGITO intervention in an early adolescent identical twin sample with co-twin controls. This would allow researchers to observe coupling effects while executive functions are still in development and give them a more concrete understanding of the self-feedback parameter grounded in developmental cascades of gene expression. A more readily available alternative would be to apply latent change score modelling to the Abecedarian Project dataset. I will end with a quote from a critic of mutualism, Gilles Gignac: I conclude with the suggestion that belief in the plausibility of the g factor (or mutualism) may be impacted significantly by individual differences in personality, attitudes, and worldviews, rather than rely strictly upon logical and/or empirical evidence. As the current evidence stands, this may be true, but with the availability of new developmental studies such as the Adolescent Brain Cognitive Development study and old ones like the Louisville twin study there’s less of an excuse than ever. Written by James Howarth Related articles: Nature vs nurture in childhood intelligence / Does being bilingual make you smarter? REFERENCES Carroll, J. B. (1993). Human cognitive abilities: A Survey of Factor-Analytic Studies . Cambridge University Press Rindermann, H., Becker, D., & Coyle, T. R. (2020). Survey of expert opinion on intelligence: Intelligence research, experts’ background, controversial issues, and the media. Intelligence , 78 , 101406. https://doi.org/10.1016/j.intell.2019.101406 Spearman, C. (1904). “General intelligence,” objectively determined and measured. The American Journal of Psychology , 15 (2), 201. https://doi.org/10.2307/1412107 Thomson, G. H. (1916). A hierarchy without a general factor. British Journal of Psychology 1904-1920 , 8 (3), 271–281. https://doi.org/10.1111/j.2044-8295.1916.tb00133.x Jensen, A. R. (1998). The g factor: The science of mental ability. Praeger Publishers/Greenwood Publishing Group Van Der Maas, H. L. J., Dolan, C. V., Grasman, R. P. P. P., Wicherts, J. M., Huizenga, H. M., & Raijmakers, M. E. J. (2006). A dynamical model of general intelligence: The positive manifold of intelligence by mutualism. Psychological Review, 113 (4), 842–861. https://doi.org/10.1037/0033-295X.113.4.842 Johnson, W., Nijenhuis, J. T., & Bouchard, T. J. (2008). Still just 1 g: Consistent results from five test batteries. Intelligence , 36 (1), 81–95. https://doi.org/10.1016/j.intell.2007.06.001 Project Gallery

The utilisation of Stonehenge as an astronomical calculator Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link The celestial blueprint of time: Stonehenge, United Kingdom Last updated: 08/10/25, 16:22 Published: 09/10/25, 07:00 The utilisation of Stonehenge as an astronomical calculator This is Article 3 in a series about astro-archaeology. Next article coming soon. Previous article: The astronomical symbolism of the Giza Pyramids . Stonehenge, located within the south-west of England, is one of the UK’s most notable man-made structures, built during the neolithic period around 3100BC. Not only is this famous UNESCO heritage site a breakthrough in engineering, but the sandstone architecture also holds an enigmatic connection between the land and the sky. Its location and stone arrangement mirrors a blueprint that can be analysed to predict the timings of astronomical phenomena. The utilisation of Stonehenge as an astronomical calculator was established by astronomer Gerald Hawkins in 1965. Using computer software, Hawkins discovered that the location of Stonehenge aligned with several solar and lunar positions. He theorised that Stonehenge was built to predict astronomical events, such as eclipses, and to determine the position of summer and winter solstices. From the shape and positions of the 19 stones that comprise Stonehenge, its ‘horseshoe’ shape could predict the lunar eclipses. A booklet titled Stonehenge: Sun, Moon, Wandering Stars , written by M.W. Postins further detailed the significance of Stonehenge in archaeoastronomy. Postins suggested two scale models, the ‘Temple model’ and the ‘Enclosure model’, which detailed the significance of each stone and its relation to different events. For example, the booklet notes that the Altar Stone, a large sandstone located in the centre of Stonehenge, was placed across the solstice axis and represents the ‘Summer solstice sunrise’. Additionally, Postins hypothesised that the five trilithons, which are the vertical stones that form the structure of Stonehenge, represented planets that can be viewed with the naked eye. These include the two lowest trilithons on the East and Northern sides of the structure, representing Mercury and Venus. There has been new research, currently underway by the universities of Oxford, Leicester and Bournemouth in collaboration with the Royal Astronomical Society, linking the Stonehenge monument to a unique lunar phenomenon, called the ‘Major Lunar Standstill’. Right from the early construction of Stonehenge, researchers note that the major lunar standstill may have influenced the design of the monument. Four of the stones at Stonehenge align with two of the Moon’s positions, which aid to indicate moonrise and moonset. This would have allowed individuals to use the moonlight for longer periods of activity, such as night time hunting, as well as visualise the cycle of the lunar phases as a method of time watching for farming and celebratory purposes. Potentially, there is speculation that this made the positioning and construction of Stonehenge intentional. The timeless effect of the Stonehenge landmark, which shaped life in the past and continues to be of astronomical interest to determine the future, is a remarkable example of the functions of built structures for the analysis of astronomical events. It truly is a celestial blueprint for the relationship between the earth and cosmology. Written by Shiksha Teeluck Related article: Astro-geography of Lonar Lake REFERENCES English Heritage. (2024). Stonehenge: Major Lunar Standstill . https://www.english-heritage.org.uk/visit/places/stonehenge/things-to-do/major-lunar-standstill/ OSR. (2009). Stonehenge: An Astronomical Calculator . https://osr.org/blog/astronomy/stonehenge-an-astronomical-calculator/?srsltid=AfmBOopNQnJ-XUZSyLY_Aqu3L2nOJgSoAceRzQJIVZbsIsFhW6s3U_NT Tiverton & Mid Devon Astronomy Society. (n.d.). Astro-Archaeology at Stonehenge . http://www.tivas.org.uk/stonehenge/stone_ast.html Project Gallery

Is bacteria the key to unlocking this treatment? Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link A breakthrough in endometriosis treatment 27/03/25, 12:05 Last updated: Published: 29/06/23, 09:16 Is bacteria the key to unlocking this treatment? In a giant leap forward, scientists have linked a specific bacterial infection to endometriosis for the very first time. Endometriosis is a condition in which the endometrium (lining of the uterus wall) grows outside of the uterus. For many women, the condition is characterised by debilitating pain, fatigue and infertility. The average time span for an accurate diagnosis is 7.5 years, with some women opting for a complete hysterectomy (removal of the uterus) to curb the pain. Unfortunately, the pathogenesis (the process by which a disease develops) of endometriosis is still relatively unknown. With previous scientific theories including retrograde menstruation, immune dysregulation, hormonal imbalance, stem cells and benign metastasis- this is the first time a bacterial theory has been forwarded. Dr Muraoka and his team theorised a link between bacterial localisation within the female reproductive tract and endometriosis- following promising research carried out on mice models. The Japanese study discovered a bacterium known as Fusobacterium to be present in the uteruses of 65% of women suffering from endometriosis, compared to less than 7% of women without the disease. Fusobacterium is a bacterium which is mostly found within the microbe of the mouth, gut and vagina. This bacterium has been linked to other inflammatory diseases such as gum disease. Follow-up studies- undertaken on mice- discovered that those treated with antibiotics saw a significant reduction in both size and frequency of lesions associated with the disease. Clinical trials are now forging ahead to investigate the effects of antimicrobials as a viable treatment option for endometriosis patients. This revolutionary study is the first of its kind and could see patient disease management progress away from medieval invasive procedures and decades of pain. For more information on Dr Muraoka and his team's work check out his study . Written by Kellie Leonard Related articles: Underreporting of endometriosis / Are PCOS and endometriosis sisters? / Gynaecology Project Gallery

Looking at caspase-8’s inability to trigger cell death Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link CEDS: a break in cell death Last updated: 12/09/25, 11:08 Published: 11/09/25, 07:00 Looking at caspase-8’s inability to trigger cell death This is article no. 11 in a series on rare diseases. Next article coming soon. Previous article: Ehlers-Danlos syndrome . Cell death, as we know it, is a crucial phenomenon by which our bodies remove unnecessary or damaged cells to maintain internal stability, a process known as homeostasis. Cell death can occur in many ways, but the mechanisms by which cells die follow two main paths. It may occur as naturally programmed, as in apoptosis, or as a result of toxic trauma or physical damage, like necrosis. While cell death due to trauma can often be more noticeable and dramatic, programmed cell death happens continually, not only because of cell damage but also because it is a normal part of development, and inducing it is a core function of immune system cells. In essence, cell death comes naturally, removing cells that are possibly damaged or infected to maintain the body as a whole. But what if cell death stops? As many fiction stories will tell you, immortality is never a good thing, and this is accurate for our cells, too. Although excessive cell death is also destructive, cell death in its natural controlled manner not only stops the spread of infection but also prevents the survival of cancer cells and auto-reactive immune cells, which can damage the body by forming cancerous tumours and triggering autoimmune diseases, respectively. This demonstrates that a careful balance of life and death must always be in place to maintain homeostatic conditions and allow our unimpeded survival. However, as cell death is a multi-step mechanism, it can go wrong in several ways. Furthermore, diseases causing faults in the cell death process can be challenging to diagnose. Not only can there be numerous reasons for patients to exhibit symptoms associated with the loss of cell death, but some of these reasons may also be rare disorders and, therefore, difficult for healthcare professionals to identify. One rare disease that researchers recently recognised is Caspase-8 Deficiency Syndrome (CEDS). This disease, stemming from a genetic mutation in the gene coding for caspase-8, results in extensive issues related to immunodeficiency, and they are all caused by caspase-8’s inability to trigger cell death. So what is Caspase-8? Caspase-8 is a pivotal regulator of the apoptotic pathway. Essentially, apoptosis can happen through two key pathways: the extrinsic pathway, when triggers originate outside the cell; and the intrinsic pathway, when the cell itself activates the cell death pathway. Whilst there are several key players in apoptosis, caspase-8 is a central mediator of the extrinsic apoptotic pathway. Caspase-8 can be activated through numerous ways, but it is often through so-called death receptors, which are typically members of the Tumour Necrosis Factor Receptor (TNFR) family of transmembrane proteins. Upon their activation, a chain reaction occurs, involving the recruitment of caspase-8 into a complex, known as the death-inducing signalling complex (DISC). This complex then cleaves further downstream caspases or the BH3 Bcl2-interacting protein. This cascade leads to DNA fragmentation, degradation of the cytoskeleton, formation of apoptotic bodies, expression of ligands for phagocytic cell receptors, and finally, uptake by phagocytes, thus completing the death of the cell and its cleanup ( Figure 2. ). Caspase-8 therefore plays a crucial role in completing the death inducing pathway. While there are other methods of cell death, the loss of Caspase-8 undoubtedly leads to significant consequences. Caspase-8 deficiency syndrome (CEDS) Scientists first discovered CEDs in the early 2000s. By this time, there had already been extensive research into a similar disease known as Autoimmune Lymphoproliferative Syndrome (ALPS), which results from defective apoptosis leading to abnormal immune cell survival. However, at the time of ALPS discovery, there was no identified link to a loss of Caspase-8. Furthermore, there was a lack of available mouse models to study, as inducing homozygous caspase-8 deficiency caused embryonic lethality in mice, significantly limiting research. Therefore, a loss of caspase-8 was also considered to have the same effect in humans. This train of thought continued until 2002, when Chun et al. conducted major studies into apoptosis-related diseases. During one of their many trials, two siblings—a 12-year-old girl and an 11-year-old boy—were found to exhibit symptoms similar to those of ALPS (lymphadenopathy, splenomegaly, and defective CD95-induced apoptosis of peripheral blood lymphocytes). However, unlike ALPS, the siblings were also immunodeficient and suffered from recurrent sinopulmonary and herpes simplex virus (HSV) infections, as well as a poor response to immunisation. Following the discovery of these additional symptoms in the siblings, researchers examined their other family members but were surprised to find that neither the parents nor another sibling suffered in a similar fashion. The only symptom they had was a partial defect in apoptosis mediated by CD95. It was determined that the mother, father, sibling, and several other extended family members were potentially heterozygous carriers of the mutation found in the affected siblings. Subsequently, a DNA analysis was conducted, and a mutation was found in the CASP8 gene. This mutation was a homozygous deletion, which ultimately led to a loss of function of the caspase-8 protein. This loss of function in caspase-8 resulted in defective interleukin 2 production and diminished T-cell proliferation, explaining the immunodeficiency associated with CEDS and highlighting the important role caspase-8 plays in regulating cell death and immune responses. Since CEDS was first identified in the 2002 study, very few cases have been reported in medical literature. However, despite this, research continues, and it has allowed further insights into caspase-8’s pathophysiology and, in many studies, new genetic variants have been identified. One such variant is a homozygous missense mutation resulting in significant immune dysregulation in an affected individual, which results in immune responses and inflammatory conditions associated with the disease. Alongside research into the causes of this disease, focus has also shifted to how we might best diagnose and treat the disease and provide patients with the good quality of life they deserve. Diagnosis As with all rare diseases, one of the main issues stopping correct diagnosis of CEDS and delaying treatment is the fact healthcare providers are not familiar with disease symptoms, let alone the genetic basis of the disease. To make matters worse, the presentation of disease varies depending on the age of onset, which makes it even more difficult to recognise CEDS as the common underlying cause. For instance, early-onset often results in symptoms, such as severe infections and organomegaly, while adult-onset patients may present with neurological issues, multi-organ failure and chronic inflammatory conditions. Further adding to these diagnostic difficulties is the fact CEDS overlaps with other conditions, such as the previously mentioned ALPs. As a result, a patient could receive multiple different diagnoses before CEDS is identified as the cause of their suffering. For effective CEDS diagnosis, expertise in immunology, genetics and infectious diseases is required. However, this specialised knowledge is hard to come by, and as with all diseases, the familiarity the healthcare provider has with it contributes greatly to whether you will get diagnoses, and this familiarity does not exist for rare diseases. Furthermore, diagnostic methods in general are tricky for this disease, with multiple tests often being required including an analysis of patient history alongside genetic testing through methods like whole exome sequencing and immunological tests analysing the types and states of immune cells and abnormal levels of immunoglobulins. Each of these diagnostic methods takes time, in an often-strained healthcare system, which can lead to a sense of helplessness in disease sufferers who only suffer more the longer they do not know what is wrong. Treatments Unfortunately for patients, a difficult diagnosis is not the only challenge they face, as there is currently no cure for CEDS, and no specific treatments. However, there are more general treatments available that could potentially alleviate symptoms and help individuals achieve some level of normality in their lives. The best possible way to approach treatment of CEDS, as with most immunodeficiency related diseases, would be to treat both the immune dysfunction and prevent recurrent infections. This could involve a multifaceted treatment plan tailored to the individual, aiming to avoid complications from immune dysfunction and improve quality of life. Potential treatment plans could include the use of antibiotic and antiviral medications for recurrent infections, and also more complex treatments such as Immunoglobulin replacement therapy (IVIG). IVIG provides necessary antibodies to bolster patients’ immune system, when they are not able to themselves, which both helps avoid overuse of antibiotic and antiviral treatments and prevents infections in the first place before treatment is required. Alongside these treatment methods, due to it being a relatively unknown disease, CEDS patients will also require a great deal of supportive and hands on care. As part of this care patients could potentially be provided with a specialised diet plan with all the correct nutrition to help them combat any gastrointestinal issues (GI’s) associated with CEDS, as primary immunodeficiency patients have found this method to help with control of GIs. In addition to current therapies several innovative approaches to treatment of genetic diseases are in development which could be used in CEDS treatment. Recent advances in gene therapy research offer new hope for treating immune deficiencies resulting from genetic defects, which means these therapies could potentially benefit CEDS patients. One promising method for gene therapy utilises CRISPR-Cas9 to correct the genetic mutations, such as those in CASP8 leading to CEDS. Another approach uses viral vectors to deliver functional genes into patients’ cells, and this could potentially deliver a functional CASP8 gene. Additionally, another very promising therapy, previously used for ALPS patients, involves genetically modifying stem cells to correct a faulty gene (such as the faulty CASP8 gene) before re-infusing them into the patient to produce healthy immune cells. These treatments could revolutionise the management of rare genetic diseases like CEDS. The future for CEDS as a rare disease Rare diseases like CEDS are often chronic and, in many cases, life threatening. Due to the scarcity of information on these conditions, few if any treatments exist. Furthermore, due to their rarity, patients of rare diseases are not only small in number but also dispersed worldwide, leading to a feeling of isolation as they rarely meet someone who shares in their experiences. However, as scientific research progresses, treatments and therapies become more effective and accessible, and with 72% of rare diseases, including CEDS, having a genetic basis, gene therapies appear incredibly promising. Yet, there is still a long way to go to fully realize their potential, and even more that can be done to help and support those who continue to suffer alone with rare diseases. Written by Faye Boswell REFERENCES Telford WG. Multiparametric analysis of apoptosis by flow cytometry. Methods Mol Biol. 2018;1678:167–202. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC8063493/ Smith C. Monitoring apoptosis by flow cytometry. Biocompare. 2017 Jan 17. Available from: https://www.biocompare.com/Editorial-Articles/332620-Monitoring-Apoptosiby-Flow-Cytometry/ Tummers B, Green DR. Caspase-8; regulating life and death. Immunol Rev. 2017 May;277(1):76–89. doi: 10.1111/imr.12541. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC5417704/ Leeies M, Flynn E, Turgeon AF, Paunovic B, Loewen H, Rabbani R, Abou-Setta AM, Ferguson ND, Zarychanski R. High-flow oxygen via nasal cannulae in patients with acute hypoxemic respiratory failure: a systematic review and meta-analysis. Syst Rev. 2017 Oct 18;6(1):202. doi: 10.1186/s13643-017-0607-1. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4439260/ Goyal A, Moitra D, Goldstein DB, Savage H, Lisco A, Rosenzweig SD, et al. Caspase-8 deficiency presenting as a novel immune dysregulation syndrome: case report and literature review. Allergy Asthma Clin Immunol. 2023;19(1):57. doi:10.1186/s13223-023-00778-3. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10084589/ Chun HJ, Zheng L, Ahmad M, Wang J, Speirs CK, Siegel RM, et al. Pleiotropic defects in lymphocyte activation caused by caspase-8 mutations lead to human immunodeficiency. Nature. 2002 Sep 26;419(6905):395–9. doi:10.1038/nature01063. Available from: https://pubmed.ncbi.nlm.nih.gov/12353035/ Khan S, Saha S, Saha S, et al. Early and frequent exposure to antibiotics in early childhood and risk of overweight: a systematic review and dose-response meta-analysis. Obes Rev. 2021;22(3):e13113. doi:10.1111/obr.13113. Available from: https://www.gastrojournal.org/article/S0016-5085(18)35036-4/fulltext Casanova JL, Abel L. Caspase-8 deficiency syndrome. Front Immunol. 2019;10:104. doi:10.3389/fimmu.2019.00104. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7750663/ Castiello MC, Villa A. Stem cell editing repairs severe immunodeficiency. The Scientist. 2024 Mar 6. Available from: https://www.the-scientist.com/stem-cell-editing-repairs-severe-immunodeficiency-71733 Ha TC, Morgan M, Schambach A. Base editing: a novel cure for severe combined immunodeficiency. Signal Transduct Target Ther. 2023;8(1):354. doi:10.1038/s41392-023-01586-2. Available from: https://www.nature.com/articles/s41392-023-01586-2https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7750663/ Project Gallery

Deconstructing allergies: mechanisms, treatments, and prevention Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Allergies 08/07/25, 16:24 Last updated: Published: 13/05/24, 14:27 Deconstructing allergies: mechanisms, treatments, and prevention Modern populations have witnessed a dramatic surge in the number of people grappling with allergies, a condition that can lead to a myriad of health issues such as eczema, asthma, hives, and, in severe cases, anaphylaxis. For those who are allergic, these substances can trigger life-threatening reactions due to their abnormal immune response. Common allergens include antibiotics like penicillin, as well as animals, insects, dust, and various foods. The need for strict dietary restrictions and the constant fear of accidental encounters with allergens often plague patients and their families. Negligent business practices and mislabelled food have even led to multiple reported deaths, underscoring the gravity of allergies and their alarming rise in prevalence. The primary reason for the global increase in allergies is believed to be the lack of exposure to microorganisms during early childhood. The human microbiome, a collection of microorganisms that live in and on our bodies, is a key player in our immune system. The rise in sanitation practices is thought to reduce the diversity of the microbiome, potentially affecting immune function. This lack of exposure to infections may cause the immune system to overreact to normally harmless substances like allergens. Furthermore, there is speculation about the impact of vitamin D deficiency, which is becoming more common due to increased indoor time. Vitamin D is known to support a healthy immune response, and its deficiency could worsen allergic reactions. Immune response Allergic responses occur when specific proteins within an allergen are encountered, triggering an immune response that is typically used to fight infections. The allergen's proteins bind to complementary antigens on macrophage cells, causing these cells to engulf the foreign substance. Peptide fragments from the allergen are then presented on the cell surface via major histocompatibility complexes (MHCs), activating receptors on T helper cells. These activated T cells stimulate B cells to produce immunoglobulin E (IgE) antibodies against the allergen. This sensitizes the immune system to the allergen, making the individual hypersensitive. Upon re-exposure to the allergen, IgE antibodies bind to allergen peptides, activating receptors on mast cells and triggering the release of histamines into the bloodstream. Histamines cause vasodilation and increase vascular permeability, leading to inflammation and erythema. In milder cases, patients may experience itching, hives, and runny nose; however, in severe allergic reactions, intense swelling can cause airway constriction, potentially leading to respiratory compromise or even cessation. At this critical point, conventional antihistamine therapy may not be enough, necessitating the immediate use of an EpiPen to alleviate symptoms and prevent further deterioration. EpiPens administer a dose of epinephrine, also known as adrenaline, directly into the bloodstream when an individual experiences anaphylactic shock. Anaphylactic shock is typically characterised by breathing difficulties. The primary function of the EpiPen is to relax the muscles in the airway, facilitating easier breathing. Additionally, they counteract the decrease in blood pressure associated with anaphylaxis by narrowing the blood vessels, which helps prevent symptoms such as weakness or fainting. EpiPens are the primary treatment for severe allergic reactions leading to anaphylaxis and have been proven effective. However, the reliance on EpiPens underscores the necessity for additional preventative measures for individuals with allergies before a reaction occurs. Preventative treatment Young individuals may have a genetic predisposition to developing allergies, a condition referred to as atopy. Many atopic individuals develop multiple hypersensitivities during childhood, but some may outgrow these allergies by adulthood. However, for high-risk atopic children, preventive measures may offer a promising solution to reduce the risk of developing severe allergies. Clinical trials conducted on atopic infants explored the concept of immunotherapy treatments, involving continuous exposure to small doses of peanut allergens to prevent the onset of a full-blown allergy. Initially, skin prick tests for peanut allergens were performed, and only children exhibiting negative or mild reactions were selected for the trial. Those with severe reactions were excluded due to the high risk of anaphylactic shock with continued exposure. The remaining participants were randomly assigned to either consume peanuts or follow a peanut-free diet. Monitoring these infants as they aged revealed that continuous exposure to peanuts reduced the prevalence of peanut allergies by the age of 5. Specifically, only 3% of atopic children exposed to peanuts developed an allergy compared to 17% of those in the peanut-free group. The rise in severe allergies poses a growing concern for global health. Once an atopic individual develops an allergy, mitigating their hypersensitivity can be challenging. Current approaches often involve waiting for children to outgrow their allergies, overlooking the ongoing challenges faced by adults who remain highly sensitive to allergens. Implementing preventive measures, such as early exposure through immunotherapy, could enhance the quality of life for future generations and prevent sudden deaths in at-risk individuals. In conclusion, a dramatic surge in the prevalence of allergies in modern populations requires more attention from researchers and health care providers. Living with allergies can bring many complexities into someone’s life even before they potentially have a serious reaction. Currently treatments are focused on post-reaction emergency care, however preventative strategies are still a pressing need. With cases of allergies predicted to rise further, research into this global health issue will become increasingly important. There are already promising results from early trials of immunotherapy treatments, and with further research and implementation these treatments could improve the quality of life of future generations. Written by Charlotte Jones Related article: Mechanisms of pathogen evasion Project Gallery

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

Treatment based on the individual's genetics Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Personalised medicine 10/07/25, 10:28 Last updated: Published: 29/04/24, 10:44 Treatment based on the individual's genetics In modern medicine, the concept of genetic risk factors is well understood. Certain individuals will be predisposed to disease based on their family history and DNA. Similar to how we inherit traits like eye colour from our parents, susceptibility to conditions such as diabetes or cancer can also be inherited. However, it is only recently that we have begun to understand that an individual's genetic makeup will affect not only their risk for disease but also their reaction to treatment. Understanding risk factors is crucial for diagnosing disease and implementing preventative measures to maintain a patient's health. Utilising a person’s unique DNA could provide insights into their genetic predisposition towards different health conditions, thus accelerating the diagnostic process. Giving patients the ability to make informed decisions about their health based on their genetic risk could help them prevent disease. For example, women carrying the BRCA1 gene may opt for mastectomies to reduce the risk of breast cancer later in life. Personalised medicine doesn’t only focus on risk; it can also directly influence how treatments are administered. Genomic data can indicate which medicines are most likely to be effective and whether there may be associated side effects. The Human Genome Project has made tremendous advancements in the last decade. Combining this data with medical records could provide doctors with insights into the molecular-level interactions of different drugs with individual patients. Personalised medicine in practice Cancer serves as the best example of the importance of personalised medicine. Patients have a unique combination of risk factors from their DNA and lifestyle. However, the same treatments are often offered to everyone with the same type of cancer. The specific mutations that cause a cell to become cancerous are unique to each patient. The genetic makeup of cancer cells may determine which treatment should be focused on, and this is where personalised medicine plays a critical role. An example of personalised medicine already in use is for lung cancer, particularly for cancers with mutated Epidermal Growth Factor Receptors (EGFRs). EGFRs are surface proteins involved in cell growth and division. If there is a mutation, it can result in unpredictable and uncontrollable cell proliferation. There are drugs specifically designed to treat lung cancer cells carrying this EGFR mutation, with their mechanism of action based on this. These drugs would likely be ineffective for lung cancers with different mutations, as they have different mechanisms of action. Personalised medicine tailors treatment to the genetic makeup of a person to achieve a bespoke and hopefully improved outcome. Transcriptomics, the study of RNA and its alterations instead of DNA, may be a future avenue of investigation in understanding cancer biology. Tumours can arise due to mutated RNA or abnormal transcription events, indicating that DNA is not the only genetic material relevant to oncology. There have been promising innovations in personalised vaccines tailored to each patient. Tissue from an individual is biopsied and studied, and using identified biomarkers, a custom mRNA vaccine can prime the immune system to attack cancer cells. Future potential Genetic variation in a patient’s response to drugs can significantly affect their reactions to treatment. By combining genomic data and AI technology, scientists are developing predictive algorithms to create individualised medication plans for patients, potentially eliminating the guesswork in prescriptions. Personalised precision medication holds great potential. However, the primary limitation currently lies in the cost of treatment. Medical services are stretched thin across the population, making bespoke treatments currently unfeasible. Personalised medicine is expected to improve as new genetic biomarkers are discovered and catalogued, leading to more sophisticated genomic databases over time. As sequencing technology becomes more mainstream, associated costs are likely to decrease, possibly making personalised medicine standard practice in the future. Written by Charlotte Jones Related article: mRNA vaccines Project Gallery

Wildlife corridors are connecting habitats previously divided by roads Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Wildlife corridors: why did the sloth cross the road? Last updated: 16/09/25, 16:49 Published: 06/11/25, 08:00 Wildlife corridors are connecting habitats previously divided by roads Have you ever run over an animal while driving, or had to suddenly hit the brakes so an animal could cross the road? Engineers and ecologists have come up with genius solutions, collectively called wildlife corridors, so that this happens less often. This article is about two such solutions - green bridges, which are big vegetated overpasses, and rope bridges between trees. More than just roadkill Roads threaten animals because of a concept called habitat fragmentation. This is when big animal populations are split into two smaller populations with less resources and less genetic diversity than the original populations. Animals may try to move between habitat fragments in search of new food or mates, but die trying to cross the road. Either they walk directly onto the road and collide with cars, or they cross by walking over power lines and get electrocuted. Wildlife corridors allow animals to safely walk over roads, un-doing the habitat fragmentation and reducing their chance of extinction. Wolves in Germany A 2021 study analysed the activity of animals crossing a green bridge in Germany. This bridge, one of seven in the state of Brandenburg, was built in 2012 over the important A12 highway ( Figure 1 ). Using camera footage over a year, researchers found that grey wolves were more likely to use the bridge at dusk, at night, and in the winter. The deer and wild boars eaten by wolves were also more likely to use the bridge at dusk and at night, so the presence of wolves on the bridge did not deter their prey. Since 76% of wolves in Germany die in road-related incidents, bridges like this one are crucial for effective wolf conservation. Rope bridges in Costa Rica While Germany’s wolves and deer walk straight onto roads, Costa Rica’s tree-dwelling animals cross the road using power lines. This means the tree dwellers, including monkeys and sloths, are at risk of electrocution - in fact, nearly 1000 animals died of electrocution in Costa Rica in 2018-19. To reduce this risk, Costa Ricans have built rope bridges across the country as a safer alternative for wildlife to cross roads. Most bridges consist of a single blue nylon rope ( Figure 2a ), while researchers at the University of Costa Rica built rope bridges specially designed for howler monkeys ( Figure 2b ). Howler monkeys were targeted because of their endangered status and ecological role as seed and pollen dispersers. While the specialised bridges doubled howler monkey populations between 2015 and 2021, both them and classic rope bridges were used by squirrels, opossums, and kinkajous. However, a 2021 study found that animals use telephone lines to cross roads as frequently as they use rope bridges, and telephone lines are dangerously close to power lines. Some species still are not crossing using rope bridges, many years after their construction. Although the rope bridges are helping to reduce electrocution, they are not perfect. Heathland in the UK Closer to home, a brand-new green bridge called Cockrow Bridge will soon open in Surrey ( Figure 3 ). Surrey has lost 85% of its lowland heath in the last two centuries, but Ockham and Wisley Commons continue to support rare heathland species like the nightjar and sand lizard. These two commons, on either side of the A3/M25 junction, will be connected by the Cockrow Bridge into a 3 km-long stretch. Although existing heathland needs to be destroyed for construction, tree stumps and soil from the destroyed habitat will be repurposed on the bridge. Tree stumps will provide shelter to small animals, while the soil contains native roots and seeds to kickstart the bridge ecosystem. Since the public will be allowed on this bridge, it will improve our access to green spaces and bring revenue to local organisations. Therefore, Cockrow Bridge is expected to benefit wildlife and the public. Conclusion Wildlife corridors could be an important conservation tool by undoing habitat fragmentation, reducing roadkill, and preventing electrocution on power lines. Examples in Germany and Costa Rica look promising, and a unique heathland bridge is under construction here in the UK. Green bridges and rope bridges prove that modern infrastructure does not need to harm biodiversity, and humans can coexist with nature. Written by Simran Patel Related articles: Gorongosa National Park / Protecting rock-wallabies in Australia REFERENCES The Sloth Conservation Foundation. Connected Gardens: facilitating the peaceful co-existence of sloths and people. [Internet]. [cited 2025 Apr 13]. Available from: https://slothconservation.org/what-we-do/habitat-connectivity/ Tobias N. Swinging to safety: How canopy bridges may save Costa Rica’s howlers. Mongabay Environmental News [Internet]. 2023 Feb 15 [cited 2025 Apr 13]; Available from: https://news.mongabay.com/2023/02/swinging-to-safety-how-canopy-bridges-may-save-costa-ricas-howlers/ Gilbey V, Petty R. UK’s first heathland green bridge. Proceedings of the Institution of Civil Engineers - Civil Engineering. 2024 Nov 1;177(6):99–110. Laidlaw K, Broadbent E, Eby S. Effectiveness of aerial wildlife crossings: Do wildlife use rope bridges more than hazardous structures to cross roads? Rev Biol Trop. 2021 Oct 1;69(3):1138–48. Plaschke M, Bhardwaj M, König HJ, Wenz E, Dobiáš K, Ford AT. Green bridges in a re‐colonizing landscape: Wolves ( Canis lupus ) in Brandenburg, Germany. Conservat Sci and Prac. 2021 Mar;3(3):e364. Project Gallery

What they are, which groups are affected, and pandemic and economic impacts Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link What are health inequalities? Last updated: 27/12/25, 17:42 Published: 08/01/26, 08:00 What they are, which groups are affected, and pandemic and economic impacts This is Article 1 in a series on health inequalities. Next article: Socioeconomic health equalities (coming soon). Welcome to the first article in a series of articles about health inequalities. This first article will look more in detail at exactly what health inequalities are. Introduction Imagine that you lived in Blackpool, and that your friends or family lived in Kensington. Your life expectancy would be 76 years, while theirs would be 86 years, a full decade of difference! Or consider the fact that even though men have shorter life-spans compared to women, women spend longer living with ill health or major illnesses. These are some examples of health inequalities, which are health differences between different groups of people. They aren’t just random variations in health outcomes between different groups or people: instead, they’re systematic and avoidable. What groups are affected by health inequalities? Health inequalities can be seen across various populations. A person’s health can be impacted by socioeconomic factors, like income or wealth, and geographic factors, like where they live. Other characteristics affecting health include ethnicity or gender. These factors don’t act in isolation. For individuals who experience multiple levels of disadvantage, the effects of inequalities are worsened. For example, ethnic minority groups who live in deprived areas, or socioeconomically disadvantaged women, experience even worse health outcomes. This interconnectedness means that understanding health inequalities and addressing them requires a holistic approach. Health status and health inequalities Differences in health outcomes can manifest in different ways. One indicator is health status, which includes overall life expectancy and healthy life expectancy, which is the time people live in good health. In England, there’s an almost 10-year gap in life expectancy between the most and least deprived areas, shown by the example above, where the life expectancy is 76 years in Blackpool and 86 years in Kensington. Differences in healthy life expectancy between the most and least deprived areas are even more pronounced. Healthy life expectancy is more than 18 years lower for the most deprived areas compared to the least deprived areas, as shown in Figure 1 . Males living in the most deprived areas can expect to live 52.3 years in good health, while for males living in the least deprived areas, this number increases to 70.5 years. For females, it’s 51.9 years in the most deprived areas, compared to 70.7 years in the least deprived. The impact of the COVID-19 pandemic on health inequalities The COVID-19 pandemic has exacerbated health inequalities, with those living in the most deprived areas and people from ethnic minority backgrounds being the worst impacted. For example, as the pandemic strained healthcare services, more deprived areas had longer waiting lists, highlighting issues of unequal access and quality of care. In addition, death rates in the most deprived areas were higher compared to the least deprived areas: at a deprivation level of 1 (most deprived), deaths from COVID-19 were 566.2 per 100,000, with this number decreasing to 228.7 deaths per 100,000 at a deprivation level of 10 (least deprived), as seen in Figure 2 . The economic impact of health inequalities Health inequalities can have economic impacts as a result of the added costs needed to address them. The persistence of health inequalities, particularly among the working-age population, is a challenge to economic growth, as increasing levels of ill health can lead to economic inactivity. For example, data from before COVID-19 suggests that health inequalities cost the UK £31bn to £33bn per year in lost productivity, £20bn to £32bn per year in lost tax revenue and higher benefits payments and £4.8bn of the NHS budget. This is equivalent to almost a fifth of the NHS budget. As the pandemic exacerbated inequalities, these numbers have only increased: for example, the long-term impacts of COVID-19 have varied between demographics. Given that at least 2.5 million working-age adults are unable to work due to long-term sickness, as per the Office for National Statistics estimates, this is a significant economic challenge for the country, as well as a health issue. Conclusion Health inequalities have been shown to affect different groups disproportionately, with deprivation, ethnicity, socioeconomic status and other social factors having compounding effects, resulting in poorer health and shorter healthy lives. The COVID-19 pandemic further exacerbated these inequalities, with the most marginalised communities being the most affected. Failure to address these differences has resulted in not only human costs but also billions in lost productivity and increased burdens on health services. Socioeconomic status is one specific factor that influences health outcomes: as mentioned above, people in the most deprived areas face a gap of approximately ten years in life expectancy compared to the least deprived, seen when comparing life expectancy in Blackpool and Kensington. The next article in this series will look more in detail at socioeconomic inequalities, so watch out for that! Written by Naoshin Haque Related article: Global Health Injustices (series) Project Gallery

This experiment was to find out the dynamic liquid viscosity of castor oil using stainless steel spheres of different radii at room temperature. Viscosity is a fluid’s resistance to flow and is formally defined as the ratio of the shearing stress to the shearing velocity. Viscosity arises due to the friction between the particles in a fluid, Go back Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Summary of a liquid viscosity experiment Last updated: 07/11/24 Published: 26/01/23 For this experiment the liquid viscosity of castor oil was determined by dropping steel spherical balls into a tube of castor oil. By considering the forces acting on the ball whilst in the fluid, it was found that the viscosity was 1.37±0.01 Pa s with a percentage error of 71.25% to the literature value of castor oil’s viscosity. This experiment was to find out the dynamic liquid viscosity of castor oil using stainless steel spheres of different radii at room temperature. Viscosity is a fluid’s resistance to flow and is formally defined as the ratio of the shearing stress to the shearing velocity. Viscosity arises due to the friction between the particles in a fluid, because as the particles slide past each other there will be work done to slide over another particle which will produce heat. For this experiment, laminar flow was a valid model for the sphere falling down the castor oil tube, because the terminal velocity of the sphere is quite small and was reached quickly so there will not be any turbulence effects. Laminar flow is defined when liquids flow smoothly with layers that do not mix, however when the layers do mix then the flow is turbulent with different layers of the fluid swirling and mixing. As the sphere was travelling through the fluid there were three forces acting on it: drag force, weight and buoyancy. This investigation can be furthered as viscosity is vital in the field of medicine. There are certain drugs that are directly injected into patients so by knowing the optimal path for the drug to be administered, the drug can reach the patient’s vital areas as quickly as possible. Overall, this experiment was interesting as it led to numerous insights as to what may have affected the motion of a sphere falling down the tube of a viscous fluid, regardless of the simplicity of the experiment. Even though the uncertainties did not overlap with the literature value and the percentage differences were very high (in part due to calculations of the momentum), the experiment was not a failure due to the scientific insight it provided to make a carry out a more accurate experiment. Written by Siam Sama Related article: Pendulum and its relation to gravity experiment