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Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Allergies 06/01/25, 13:55 Last updated: 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

Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Digital innovation in rural farming 24/09/24, 11:00 Last updated: Transforming agriculture with computer science With their rich agricultural heritage and significant contribution to the national economy, rural farming communities have always been at the forefront of agricultural innovation. Today, as the world undergoes rapid digital transformation, the integration of computer science has emerged as a game-changer in the agricultural sector. By harnessing the power of emerging technologies and data-driven approaches, farmers can enhance productivity, optimize resource allocation, and foster sustainable farming practices. This article delves into the role of computer science in revolutionizing agriculture and farming practices in rural areas. From precision agriculture and data analytics to the utilization of IoT, drones, and decision support tools, we explore how technology-driven solutions are shaping a new era of agriculture, promising increased efficiency, reduced environmental impact, and improved livelihoods for farmers. A recent report revealed that farmers in various regions, specifically rural and eastern regions such as Punjab, India have faced significant challenges, including crop failures, leading to distress and financial difficulties. It is important to address these issues and prevent the associated consequences. Digitalization within the farming industry can play a vital role in mitigating these challenges and fostering resilience. So how exactly can rural farming benefit from digitalization? Precision agriculture and data analytics: the implementation of precision agriculture techniques, supported by data analytics, can enable farmers to optimize resource utilization, improve crop management, and mitigate agricultural risks. By analysing data related to weather patterns, soil conditions, and crop health, farmers can make informed decisions, enhance productivity, and reduce the incidence of crop failures. Market intelligence and price forecasting: computer science tools can facilitate better market intelligence and price forecasting, empowering farmers to make informed decisions about crop selection, timing of harvest, and market strategies. Access to real-time market data, coupled with predictive analytics, can help farmers negotiate fair prices and reduce financial vulnerability caused by market instability. Remote sensing and drone technology: utilizing remote sensing and drone technology can enable efficient crop monitoring, early detection of diseases, and targeted interventions. High-resolution imagery and computer vision algorithms can identify crop stress, nutrient deficiencies, or pest outbreaks, allowing farmers to take timely action, reduce crop losses, and enhance yield. Decision support systems: the introduction of decision support systems can provide customized recommendations to farmers, incorporating data from multiple sources such as weather forecasts, market trends, and agronomic best practices. These systems can assist farmers in making well-informed decisions regarding crop selection, input usage, and resource allocation, ultimately improving their profitability, and reducing financial distress. The integration of computer science offers promising avenues for addressing the complex challenges faced by farmers in rural areas. By harnessing the power of data analytics, IoT, drones, and decision support tools, farmers can benefit from enhanced agricultural practices, improved market access, and financial stability. However, it is crucial to ensure the accessibility and affordability of these technologies, coupled with comprehensive support systems and policy reforms, to truly empower farmers and create sustainable change. By Jaspreet Mann Related article: Revolutionising sustainable agriculture through AI Project Gallery

Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Anticancer Metal Compounds 03/06/24, 14:57 Last updated: How metal compounds can be used as anti-cancer agents Metal compounds such as Platinum, Cobalt and Ruthenium are used as anticancer agents. Anticancer metal compound research is important as chemotherapy is not selective, being very toxic to patients damaging normal DNA cells. Such metal compounds act as anti-cancer agents with the metals being able to vary in oxidation states. Selectivity of metal compounds to target only cancer cells arises from the metals properties of varying oxidation states for redox reactions. As cancer exists in hypoxic environments, the oxidation state of the metal is able to vary releasing the cancer drug only in the cancer environment. For example prodrugs are relatively inert metal complexes with relatively high oxidation states. PtIV, and CoIII are selective carriers undergoing reduction by varying the metals oxidation state in cancerous hypoxic environments releasing anticancer drugs. CoIII reduced to CoII, PtIV reduced to PtII in hypoxic environments. CoIII two oxidation states: Cobalt (III) is kinetically inert with low-spin 3d6 configuration, CoII is labile (high-spin 3d7). When CoIII is reduced to CoII in hypoxic environments, the active molecule is released then restored to its active form killing cancer cells. Cobalt can also bind to ligands like nitrogen mustards and curcumin ligands, exhibiting redox reactivity for cancer therapy. Nitrogen mustards are highly toxic due to their DNA alkylation and cross-linking activity. In vivo they are not selective for tumour tissue however can be deactivated by coordination to CoIII, released on reduction to CoII in hypoxic tumour tissue. This reduces systemic toxicity concluding an efficient anticancer drug. Platinum anticancer metal compounds treat ovarian, cervical and neck cancer. Platinum ( Pt IV) (cisplatin) exhibits redox-mediated anticancer activity, highly effective towards tumours. Platinum causes severe side-effects for patients so PtIV prodrug is used selectively reducing tumour sites. Ruthenium is used for cancer therapy as a less toxic metal over platinum. Ruthenium targeted therapy selectively disrupts specific cellular pathways where cancer cells rely for growth and metastasis. Reduction of Ru (III) to Ru(II) selectively occurs in hypoxic reducing environments where tumours over express transferrin receptors, ruthenium binding to. Overall metal compounds for cancer treatment attracted high interest due to redox activity properties. Metal compounds are selective to cancer cells, limiting patients' side effects. Such therapy shows how inorganic chemistry is important to medicine. By Alice Davey Related article: MOFs in cancer drug delivery Project Gallery

Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Exposing medication to extreme heat 08/10/23, 16:18 Last updated: And its chemical effects Introduction The majority of us look forward to when summer is just around the corner. It is a time for parents to start planning days off to be able to go on holiday with their kids to relax from their studies and enjoy sunsets at the beach. But for people who take medication, whether this just be a week-long course of antibiotics or for long-term conditions, summer may also be a chance for some negligence to occur. Specifically, alongside making sure you have applied SPF to protect your skin from the sun’s rays, you should also protect your medicine as well. This applies to both oral and non-oral drugs. Experts at The Montreal Children’s Hospital say that “many prescription drugs are very sensitive to changes in temperature and humidity”; in this article, we will therefore discuss the effect of extreme heat on drugs from a medicinal chemistry perspective. Factors affecting drug activity due to heat Certain drugs may begin to degrade before their expiry date if not stored appropriately. This affects the efficacy, which is the maximum biological response that is achievable with a certain drug. A dose-response curve can be plotted (see Figure 1 ) to show the relationship between the two variables; the label Emax refers to the efficacy. During hot weather, the structure of the drug can change and therefore unable to bind to its target, causing a lowered and shifted Emax to be seen. Simply put, the medication will not relieve your symptoms as effectively. Another physiochemical property of a drug that can be altered in the heat is the potency. Many people confuse this term with efficacy, but potency refers to the concentration of a drug required to achieve 50% of its maximum therapeutic effect i.e., half the Emax. Potency is therefore also known as EC50, which abbreviates for ‘half maximal effective concentration’. The lower the concentration needed, the more potent your drug is. Like reduced efficacy, the drug’s potency will also decrease in the heat due to altered chemical structure. For drugs like antibiotics, it is crucial to note that if potency is reduced significantly, it could risk infection spreading to other parts of the body as the medication will not fight off bacteria as well as it should. Potentially dangerous! Finally, drug absorption is when a drug moves into the bloodstream after being administered. The chemical structure of the drug and the environment in which it is present hugely affects this; for example, if a lipophilic (‘fat loving’) drug is also present in a lipophilic surrounding, fast absorption is seen as they work well with each other. As you have probably guessed, high temperatures outside of the body can reduce drug absorption due to the above factors mentioned, as the drug is not in its optimal structure to be absorbed effectively. Examples of medicine that are heat sensitive Here is a list of some medicines that require extra care to prevent the above: 1) Nitroglycerin – used to treat chest pains for those with cardiovascular disease. It is especially sensitive to heat or light as it degrades very fast. Dr. Sarah Westberg, a professor at The University of Minnesota College of Pharmacy, says you should follow the storage instructions and replace them regularly. 2) Some antibiotics – research has shown that ampicillin, erythromycin, and furosemide show a reduction in activity in the heat, although this was found after storing them for a year in a car with a temperature exceeding 25 degrees Celsius. Other antibiotics such as cefoxitin are shown to have some “stability in warmer climates”. 3) Levothyroxine – used to treat an underactive thyroid, also known as hypothyroidism. This drug should be stored between 15 to 30 degrees Celsius, although even 30 is quite high so the lower the temperature the better. Interestingly, levothyroxine isn’t heat sensitive itself, it is the fact that the body becomes sensitive to the drug and may make a person feel strange in the heat. 4) Metoprolol succinate – used to treat high blood pressure, also known as hypertension, and heart failure in emergencies . The ideal storage conditions for this drug are 15 to 30 degrees Celsius, like Levothyroxine. Key things to look out for with your medicine in the heat Below are the 2 main things you should be checking for before taking your medicine in the summer: 1) Change in colour – Light can initiate all sorts of reactions, such as oxidation. If, for example, your medicine that is normally white has now changed into a different colour, this suggests that a reaction has taken place within your drug and will not be effective when administered. 2) Change in texture – Similar to change in colour, if a normally solid, oral tablet has become soft then this also suggests that the medication will not be as effective when consumed. How you can prevent your medicine from degrading To make sure you do not contribute to wasting medicine, you should do the following: 1) Check storage information – for any medication that you take, this will let you know how to store them correctly. 2) Travel with care – do not pack prescription drugs into your luggage, as it will almost always become very warm due to the surrounding environment. Instead, carry your medicine with you with the labels still on. 3) Do not leave medicine in any vehicle – everyday vehicles such as cars tend to get warm after a period , which can affect the colour and texture of your medicine. 4) Careful deliveries – for those who have their medicine delivered to them, you can request for your local pharmacy to deliver your medicine in temperature-controlled packages. Summary As discussed, chemicals in the majority of over-the-counter prescription drugs are heat sensitive and should therefore be handled with care, to prevent degradation of the drug. Changes in colour and texture are signs of degradation, which result in loss of efficacy, absorption, and potency. However, many other pharmacological factors interfere, so scientists especially involved in drug synthesis should (or continue to) take great precautions with the manufacturing process. Drugs are costly to make and require a lot of time, so the takeaway is to store them correctly! You should contact your pharmacist if you are still unsure about your prescription(s). Written by Harsimran Kaur Sarai Project Gallery

Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Behavioural Economics I 06/01/25, 13:59 Last updated: The role of honesty This article is part 1 in a four-part series on behavioural economics. Next article: The endowment effect . In the classical realm of economic theory, consumers are said to be utility maximisers. These economic agents will always prefer a situation where they can increase their utility (a measure of well-being or happiness) and will achieve this by any means necessary. Given the opportunity, economic agents will take advantage of others and abuse their power, and although this can be true in many aspects of life, in this article we will explore why people are intrinsically honest, defying classical economic theory, giving a brief insight into how we can explain economic behaviour through the power of behavioural economics. ‘Lost Wallets’ In an effort to measure civic honesty around the globe, Cohn et al. devised a comprehensive study to measure whether people's own material incentives were able to overpower their innate sense of honesty and altruism all together. By distributing over 17,000 ‘lost wallets’ in over 40 countries, Cohn et al. were able to surprisingly prove that people are more honest than we take each other to be. The experiment was simple but comprehensive. A group of people in many different countries would hand in a ‘lost’ wallet to a desk in public areas, for example at a hotel desk or at a library. The wallet contained three business cards - a way to contact the owner, a grocery list, and a key to make it seem more legitimate. Another important detail was that the wallets were transparent, so the receiver did not have to open the wallet to see its contents. The reason why this is important is because some wallets contained money in them, and we wanted to see if this impacted the decision to hand the wallets in or not. In classic economic theory, we would expect that wallets with money in them would not be returned, but instead the receiver would take the money freely. They may be more inclined to return the wallet without money as there would be little benefit in keeping them. However, in real life, this could not be any further from the truth. In 38/40 of the countries, lost wallets were handed back more often when they contained money. Civic honesty was found to be statistically higher when the wallets were not empty. So why are people more likely to hand back their wallets when they contain money? Surely that’s counterintuitive? Well, in fact, one strong explanation is that people value honesty due to their own self-image. If we take the money, our own view of our perfect self becomes threatened, so that the psychological effect of taking the money is greater than the money’s value itself. Similarly, when the wallet contains only business cards, the receiver cannot see any intrinsic value in the wallet. The psychological value of handing the wallet back is now far less worth the effort of making contact with the owner. We disregard the wallet before we even know its contents. Another interesting fact is that when there is a big money condition (7x what was used initially), we find that people are even more likely to report the missing wallet. One explanation may be that with a greater stake, there is also a greater psychological reward for handing the wallet back. When doing an act of kindness as simple as this, people often feel good about themselves, boosting their own ego, and this could be perceived to be greater than the value of their wallet. If the combination of threatened self-image with the positive psychological value of returning the item is much greater than the monetary value of the ‘lost wallet’, then people are likely to return the wallet. In fact, the study showed that over 70% of the wallets were returned when it contained a substantial sum of money. ‘Dice in a Cup’ The second study that I wish to use to describe the effect honesty has on society, is one that involves an extremely simple setup. There is a benefit to having simple experiments in a lab setting. When people volunteer to participate in a lab-controlled experiment, they realise they are being watched (unlike with the previous experiment, which was performed on unsuspecting subjects). This often means that people put in fake answers—the answers they think we wish to hear—which aren’t useful to us. The way we get around this is by putting incentives in place and encouraging people to act the way they would in real life and by ensuring that the experiment is simple, there is no chance that a subject could misinterpret the rules of the experiment. The die-in-the cup experiment run by Gachter and Schulz did just that. Subjects were told to enter a room, and in the middle of the room sat a table with a die placed on top. The subjects were instructed before they entered the room to roll the die twice and then report the first roll of the die only. The number they reported then corresponded to a payout of the following: 1 = £1, 2 = £2... 5 = £5, and 6 = £0. (The pay-out for different countries were in their corresponding currency of equivalent value.) The aim of this experiment is to examine the amount of honesty in a society, and in this paper, they compared this with the presence of rule violations across different societies and looked for a relationship. They discovered that the inhabitants of wealthier countries are more honest on average. In classical economics, if everyone was ‘rational’, they would lie to get the maximum payout every time. This would give an average payout of £5. On the other hand, if everyone was completely honest, the average payout would be £2.50. In the experiment, the mean payout across all countries was around £3 (around £2.90 for the richer nations and up to as high as £4 for the poorer nations). What this tells us is that people are dishonest, but not fully dishonest. One possible explanation is that people would ‘justify dishonesty’. By choosing the higher of the two rolls, people feel less bad about lying completely and bend the rules in their favour. Another explanation is that people take the second-best outcome. In the fear of people being suspicious of them, subjects may decide to say 3 or 4 instead of 5 if, for example, they rolled a 1. But why don’t people lie and say they get a 5 every time? One theory is that people’s desires conflict with their perception of an honest self-image. Like with the lost wallets experiment, people feel guilty by lying completely, but by changing the rules slightly or not taking the highest payout, the benefit of lying is greater than any negative self-perception as in their eyes, they are not lying completely. People are only as dishonest as they can be whilst maintaining a ‘honest’ self-image. So, as we have shown, the foundation of economics can indeed fall short. The basis that people are utility maximisers is not necessarily true in all circumstances, such as when maximising utility violates self-perception. However, this is not to say that we have disproved all of economics. Economics provides an insight into how people and systems in society interact in an ideal setting, which is still beneficial for understanding what a policy is needed to achieve, but behavioural economics can be used to develop the policy further so that its implementation is more seamless. To learn even more about the developments in this ongoing discipline, be sure to follow Scientia News on social media and don’t forget to look out for Part 2 in this new 4-part series discussing the realm of behavioural economics! Written by George Chant Related article: Mathematical models in cognitive decision-making REFERENCES Alain Cohn et al., Civic honesty around the globe. Science 365,70-73(2019) Gächter , S., Schulz, J. Intrinsic honesty and the prevalence of rule violations across societies. Nature 531 , 496–499 (2016) Project Gallery

Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Artificial intelligence in space 21/11/24, 12:08 Last updated: AI in developing space technologies Artificial intelligence or AI has become an important force or a tool that drives the evolution of technologies that improve human life and helps unlock the secrets of the universe beyond the influence of our planet. In simple words, AI is something that enables a computer/ robot to mimic human intelligence and it is revolutionizing the way we explore and utilize space, enhancing everything from spacecraft navigation and autonomous decision-making to data analysis and mission planning. This article explores the profound impact of AI in the development of space related technologies. Mission planning and design Space mission planning and payload, instrument designs rely on the gathered previous mission data. However, access to all the historic mission data is only provided to individuals with a higher authority access at the space agency which requires a lot of paper works and approvals. But recently NASA came up with a solution and they named it as the “Data Acquisition Processing and Handling Network Environment” (DAPHNE) system. Daphne is an AI assistant which can access millions of previous mission data including the most restricted ones and provide the scientists an insight about their mission without the need of a higher authority access or security clearance. It can also compute and analyze countless input variables to determine the most efficient routes and schedules for missions, which is crucial for long-duration missions or missions with multiple objectives. Manufacturing Manufacturing processes usually involves complex tasks that requires high precision and attention to detail when it comes to space related applications. The use of AI in spacecraft manufacturing not only accelerates production but also increases precision and reliability. Ai assistants like collaborative bots (cobots) interacts with the engineers and help them to make the right decisions, reduce the overall assembly process time and also provide insights about the final product which ensures that the spacecrafts are built to the highest standards. Data processing Space missions generate vast amounts of data, from images and telemetry to instrument readings. AI algorithms are capable in sifting through this data, identifying patterns, and extracting meaningful insights. An example is the estimation of planetary wind speed which requires a combination of the satellite imagery and meteorological data. AI tools can rapidly analyze these large datasets and help scientists in understanding these planetary phenomena and easily uncover its secrets. This capability is also valuable in missions to study distant galaxies, black holes, and exoplanets. Navigation & guidance systems One of the critical applications of AI in space technology is autonomous navigation. Spacecraft traveling vast distances through the cosmos must constantly adjust their trajectories to avoid collisions with celestial bodies and maximize their fuel efficiency. Advanced AI systems can process data in real-time and autonomously adjust a spacecraft's course. This not only reduces the need for constant human intervention from the ground station but also allows for more precise and efficient missions. Astronaut health monitoring Astronauts in space face a range of health issues like bone density loss, cardiovascular issues etc. The AI systems can continuously monitor physiological data and provide an insight into the astronaut’s health condition including sleep patterns. This allows early detection of health issues and timely intervention which reduces the need for immediate communication with ground mission control, ultimately safeguard the safety of the astronauts on long-duration missions. In summary, AI is a tool that represents a transformative shift in how we explore and understand our cosmos and its secrets. One day AI will play an even more significant role in the future that pushes the boundaries of space and bring us closer to answering some of humanity’s most profound questions. Written by Arun Sreeraj Related articles: Astronauts in space / AI in drug discovery / Evolution of AI / Chemistry in space exploration Project Gallery

Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Hubble Tension 15/06/24, 13:27 Last updated: Why the fuss over a couple of km/s/Mpc? You have probably heard that the universe is expanding, and perhaps even that this expansion is accelerating. A consequent observation of this is that distant objects such as galaxies appear to recede from Earth faster if they are further away. Here is a helpful analogy: imagine a loaf of raisin bread that is rising as it is baked. A pair of raisins on opposite sides of the loaf will move away from one another at a greater rate than a pair of raisins near the center. The more dough (universe) there is between a pair of raisins (galaxies), the faster they recede from one another. See Figure 1 . This phenomenon is encapsulated in Hubble’s Law, which relates specifically to the recessional velocity due to the expansion of space. Hubble’s Law is given by the equation v = H0 D . Where: v is the recessional velocity D is the distance to the receding object H0 is the Hubble constant It is worth noting that distant objects will often have velocities of their own due to gravitational forces - so-called ‘peculiar velocities’. In order to clarify the meaning of the title of this article, we must explore the unit in which the Hubble constant H0 is most often quoted: km/s/Mpc. This describes the speed (in kilometers per second) at which a distant object, such as a galaxy, is receding for every megaparsec of distance that galaxy is from Earth. Edwin Hubble is the name most often associated with this cosmological paradigm shift; however, physicists Alexander Friedmann and Georges Lemaître worked independently on the notion of an expanding universe, deriving similar results before Hubble verified them experimentally in 1929 at the Mount Wilson Observatory, California. What is the Hubble Tension? Hopefully the above discussion of units and raisin bread convinced you that the Hubble constant H0 is linked to the expansion rate of the universe. The larger H0 is, the faster galaxies are receding at a given distance, thus indicating a more quickly expanding universe. Therefore, cosmologists wish to accurately measure H0 in order to draw conclusions about the age and size of the universe. The Hubble Tension arises from the contradicting measurements of H0 obtained from different experiments. See Figure 2 of Edwin Hubble. CMB measurement One of these experiments uses the Cosmic Microwave Background (CMB), which can be thought of as an afterglow of light from near the time of the Big Bang. The wavelength of this light has expanded with the universe ever since the period of recombination - which I mentioned in my previous article on the DESI instrument. Our current best model of the universe, called ΛCDM, can describe how the universe evolved from a hot, dense state to the universe we see today, subject to a specifically balanced energy budget between ordinary matter, dark matter, and dark energy. From fitting this ΛCDM model to CMB data from missions such as ESA’s Planck Mission, one can derive a value for the expansion rate of the universe, i.e., a value for H0 . The Planck Mission measured temperature variations (anisotropies) across the CMB with unprecedented angular resolution and sensitivity. The most recent estimate for the Hubble constant using this method gave H0 = 67.4 ± 0.5 km/s/Mpc . Local Distance Ladder measurement Another technique to determine the value of H0 uses the distance-redshift relation. This is a wholly observational approach. It relies on the fact that the faster an object recedes from Earth, the more the light from that object is shifted towards longer wavelengths (redshifted). Hubble’s Law relates this recessional velocity to a distance; therefore, one can expect a similar relation between distance and redshift. A ‘ladder’ is invoked since astronomers wish to use objects that are visible from a vast range of distances; the rungs of the ladder represent greater and greater distances to the astronomical light source. Each rung of the ladder contains a different kind of ‘standard candle’, which are sources with reliable, well-constrained luminosities that translate to an accurate distance from Earth. I encourage you to look into these different types; some examples are Cepheid variables, Type Ia Supernovae, and RR Lyrae variables. When this method was employed using the Hubble Space Telescope and SH0ES (Supernova H0 for the Equation of State), a value of H0 = 73.04 ± 1.04 km/s/Mpc was obtained. The disagreement Clearly, these two values for the Hubble constant do not agree, nor do their uncertainty ranges overlap. Figure 3 shows some of the 21st-century measurements of H0 ; an excellent illustration of how the uncertainty has decreased for both methods, therefore making their disagreement more statistically significant. Many sources of scientific engagement with the public cite this disagreement as the ‘Crisis in Cosmology!’. In the author’s opinion, this is unnecessarily hyperbolic and plays on the human instinct to pick a side between two opposing viewpoints. In fact, new methods to measure H0 have been implemented using the tip of the Red-Giant branch (TRGB) as a standard candle, which demonstrate closer agreement with the value derived from the CMB. Some cosmologists believe that eventually this Hubble Tension will dissipate as our calibration of astronomical distances improves with the next generation of telescopes. Constraining the value of the Hubble constant is by no means low-hanging fruit for cosmologists, nor is the field in crisis. To see the progress we have made, one has to look back in time to 1929 when Edwin Hubble’s first estimate using a trend line and 46 galaxies gave H0 = 500 km/s/Mpc ! We must remain hopeful that the future holds a consistent approximation for the expansion rate and, with it, the age of our universe. Written by Joseph Brennan Project Gallery

Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link How to excel in maths 06/01/25, 13:46 Last updated: Strategies for success and mathematical mastery Mathematics is a subject that can be both daunting and rewarding. While some individuals seem to effortlessly grasp mathematical concepts, most of us need to put in extra effort to excel. This article is dedicated to the majority—the ones willing to work hard to achieve success in their A-level maths exams and beyond. By following a structured approach and embracing a growth mindset, you can unlock your mathematical potential and reach heights you may have never thought possible. Understanding the concepts Fundamentally, to be able to get anywhere in mathematics, you need to understand what you are doing with numbers and why. There is no point in knowing how to differentiate if you don’t know why you want to differentiate and why it works. Now, I am a strong believer that anyone can learn anything if they approach it with an open mind and determination to succeed. This is called having a growth mindset. However, there is a caveat with how maths is taught at school. When maths is taught, it is taught by someone who understands a concept in a particular way. We are all inherently different, and similarly, our minds all work slightly differently. So when your teacher explains how they understand something, it does not mean that you should also understand it as you both think differently. Now for some, they manage to grasp what their teacher is saying easily as they think similarly, but for others this may need an alternative approach. Some examples could be supplementary lessons with a tutor, buying a subscription to online lessons or asking for some 1-on-1 time with your teacher. But sometimes this may still not even work. If my teacher can’t help me, how can I learn? Well, for A-Levels and GCSEs, we are extremely blessed that there is a plethora of different resources that we can use, both written and in video format! Some of my favourites include, but are not limited to, TLMaths (Youtube), BBC Bitesize (GCSE only), and Khan Academy. (Also see: Extra Resources for more maths resources). YouTube really can be your best friend. There are thousands of videos explaining mathematical concepts, and they are not all as trivial as those shared by Numberphile. By simply searching for a topic that you are stuck on, you can get many different professionals to explain the same problem; with enough grit and determination, you’ll be able to find a video that you can easily understand! If, however, that does not seem to work, it may be an indicator that you need to step back and learn the fundamentals a bit better. There is little point in using the integral to calculate the area under a line graph if you don’t know what a line graph actually shows. Practice the concepts Once you’ve got the concepts down to the tee, there is only one option to go with. Practice. Practice. Practice. I foolishly made the mistake during my year 10 final exams, where instead of doing practice questions, I made notes from watching videos and thought that was enough. Not only is this not engaging, but when it comes to maths, practice is the only way to revise. Truthfully, I would never recommend taking notes in maths as it is not only quicker to look something up, but I believe the time spent making notes could be spent better elsewhere. The best way to practice for an exam is through practice papers. You may now be dashing off to find practice papers for your exam board; however, I would recommend not touching these until you are around 1 month away from your exam. If you are as crazy as I am, you could even leave it until the last week and complete 2 or 3 per day, but maybe for your sanity, I’d advise against this. Instead, use all of the resources that you are fortunate enough to have available to you thanks to the internet. Complete every question in your textbook and revision guide; complete predicted papers; do it all! This is the surefire way to get top marks and become a competent mathematician. But maybe you’re not studying for a big A-level exam just yet. By completing the questions that you may not have done in class and researching topic-specific questions (Math’s Genie and Physics and Maths Tutor are both excellent resources for this), you will, with time, start to develop your skills and put the theory into practice. By better applying these concepts, you begin to understand them and maybe even start to enjoy them. (Bonus tip: do your homework. It’s given out for a reason.) Apply the concepts to unfamiliar situations Now that you have mastered the concepts and put them to the test by answering every question you can get your hands on, comes the trickiest part of mathematical mastery: These are the questions that separate the A’s and the A*’s. The geniuses and the sedulous, but more importantly, those who can do maths, and those who understand maths. By applying the mathematical concepts that you’ve learned to unfamiliar situations, you start to develop an extremely sought-after skill. Problem solving. By using maths in an unfamiliar context, most students are hasty to give up, and this is why the last question on the test is so ‘difficult’, but in fact it's the same as the prior questions but in disguise. To conquer these questions, you have to be able to decipher what the question is asking and then apply the appropriate techniques to solve it. The only way that you will know which techniques to use is by attempting similar questions that push you, and in time, your brain's pattern recognition will kick in and you’ll start to find that you just know what to do. You can't explain it; you just want to differentiate here, factor out here, and expand these brackets here, and bam! You’ve got the answer. But the only way you can get there is by putting in the hours and attempting questions that are outside your comfort zone. At the beginning of the article, I said it would be tough, but maths does not require you to spend 4 hours every night (until you are smack in the middle of your A-level exams), but instead a mere 20 minutes, maybe only 5 days a week, but I promise you that this small amount of time after school, before bed, or during break, if uninterrupted and follows the rules that I have just suggested, will work absolute wonders on your mathematical ability. Imagine the impact of dedicating just 20 minutes a day to math starting right now. If you're in year 13, with your first math paper 38 weeks away on June 4th, time will fly. By committing to 20 minutes daily, five days a week, you'll accumulate over 63 hours of revision. Bump it up to half an hour, and you'll hit almost 100 hours. This early start saves you precious time closer to exams, allowing you to focus on other subjects. Unlike some subjects, math doesn't require rote memorisation. Building these skills gradually pays off. Yes, 20 minutes daily may seem modest, but consistency can be challenging. Skipping just one day can turn into a week, then a month. Dedication, determination, and discipline are essential for success. If you maintain this routine, you can achieve remarkable results, even surpassing natural mathematical geniuses. Now with the three steps to mathematical freedom: Understand the concepts. Practice the concepts. Apply the concepts to unfamiliar situations. Go out there and give it your best shot! I wish you all the best of luck in your journey to mathematical mastery! Written by George Chant Related articles: The game of life / Teaching maths / Topology Project Gallery

Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Antiretroviral therapy: a key to helping HIV patients 28/11/24, 12:01 Last updated: Most research studies are now being diverted to Antiretroviral Therapy (ART) Human Immunodeficiency Virus, commonly called HIV, is a sexually transmitted disease that affects approximately 40 million people worldwide and is mostly common in ages 15-49 years. It is spread through direct contact with the blood, semen, pre-seminal fluid, and vaginal fluids of an infected person through mucous membranes—contact with male and female genital tracks. Additionally, HIV can be spread through breast milk from mother to child—studies have shown that infants likely contract the virus when the milk makes contact with the mucous membranes of the gut. How does HIV affect immune cells? HIV is a retrovirus—enveloped RNA viruses that can evade the immune defense system and live within host cells indefinitely. To infect cells HIV uses several mechanisms to make contact with the host cell's membrane. This involves the binding of HIV envelope protein (Env) with the cell receptor CD4 of an immune cell (T-helper cells). Env then binds to a co-receptor on the surface of the cell membrane, triggering membrane fusion. Membrane fusion leads to formation of a fusion pore where HIV successfully enters into the cell's cytoplasm through. Following this, HIV converts its RNA to DNA using enzyme reverse transcriptase and then uses integrase enzymes to become a permanent part of the host cell’s DNA. This allows HIV to replicate at a rapid rate, eventually causing the cells to bloat and rupture, killing the cell all while also “hiding” from the immune defense system and going into latency. Such a process is what weakens the immune system as there is a significant depletion in T-helper cells—cells that fight off infections and diseases. The evolution of ART For the reasons above, HIV is almost impossible to cure. While research is still being conducted to find a cure for HIV, most studies are now being diverted to Antiretroviral Therapy (ART). ART is a revolutionary treatment introduced in the late 198 0s that aims to prevent transmission of HIV, prolong survival, improve immune function and increase CD4 cell count, and improve overall mortality. The first drug released in the late 1980’s was Zidovudine, a nucleoside reverse transcriptase inhibitor (NRTI) that essentially prevents HIV’s RNA from being converted to DNA. This restricted replication hence increasing T-helper cell count. However, while shown to improve the condition of HIV patients, zidovudine did not work well on its own and caused drug resistance from prolonged use. Combination therapy was later introduced where scientists discovered zidovudine to be effective when used alongside another NRTI (dideoxycytidine). This combination did improve CD4 cell count and the overall condition of most patients, not in patients with advanced HIV who had prior use of zidovudine alone. Now, several medications such as NRTI’s, non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors, and integrase inhibitors have been introduced and are used in a combination of three (Triple-Drug Therapy) to help suppress viral load to undetectable levels in the blood and improve the overall quality of life for patients. Triple-drug therapy can be tailored by doctors to improve the patient's condition. HIV is a sexually transmitted, chronic condition that affects less than 1% of the world's population. There is no cure for HIV, however, treatments (ART) have been introduced to reduce the viral load of HIV as well as improve the overall quality of life of patients. Compared to the past where these medications had to be taken multiple times a day, often causing severe side effects, patients can now take just a single tablet daily. This has changed the course of HIV treatment, allowing people to live lengthy, normal lives with the disease. Written by Sherine A Latheef Related article: CRISPR-Cas9 to potentially treat HIV REFERENCES Guha D, Ayyavoo V. Innate immune evasion strategies by human immunodeficiency virus type 1. ISRN AIDS . 2013;2013:954806. Published 2013 Aug 12. doi:10.1155/2013/954806 AlBurtamani N, Paul A, Fassati A. The Role of Capsid in the Early Steps of HIV-1 Infection: New Insights into the Core of the Matter. Viruses . 2021;13(6):1161. Published 2021 Jun 17. doi:10.3390/v13061161 Pau AK, George JM. Antiretroviral therapy: current drugs. Infect Dis Clin North Am . 2014;28(3):371-402. doi:10.1016/j.idc.2014.06.001 Mayers, Douglas L. “Prevalence and Incidence of Resistance to Zidovudine and Other Antiretroviral Drugs.” The American Journal of Medicine , vol. 102, no. 5, May 1997, pp. 70–75, https://doi.org/10.1016/s0002-9343(97)00067-3 . Accessed 5 Dec. 2021. “Antiretroviral Drug Discovery and Development | NIH: National Institute of Allergy and Infectious Diseases.” Www.niaid.nih.gov , www.niaid.nih.gov/diseases-conditions/antiretroviral-drug-development#:~:text=D urable%20HIV%20Suppression%20with%20Triple%2DDrug%20Therapy&text=In %20December%201995%2C%20saquinavir%20became. CDC. “How HIV Spreads.” HIV , 14 May 2024, www.cdc.gov/hiv/causes/index.html . clinicalinfo.hiv.gov . (n.d.). Protease Inhibitor (PI) | NIH . [online] Available at: https://clinicalinfo.hiv.gov/en/glossary/protease-inhibitor-pi . www.who.int . (n.d.). HIV . [online] Available at: https://www.who.int/data/gho/data/themes/hiv-aids#:~:text=Globally%2C%2039.9 %20million%20%5B36.1%E2%80%93. Project Gallery

Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Chirality in drugs 24/09/24, 10:55 Last updated: Why chirality is important in developing drugs Nearly 90% of the drugs currently on the market are racemates, which are composed of an equimolar mixture of two enantiomers, and approximately half of all drugs are chiral compounds. Chirality is the quality of an item that prevents it from superimposing on its mirror counterpart, similar to left and right hands. Chirality, a generic characteristic of "handedness,"plays a significant role in the creation of several pharmaceutical drugs. It's interesting to note that 20 of the 35 drugs the Food and Drug Administration (FDA) authorised in 2020 are chiral drugs. For example, Ibuprofen, a chiral 2-aryl propionic acid derivative, is a common over-the-counter analgesic, antipyretic, and anti-inflammatory medication. However, Ibuprofen and other medications from similar families can have side effects and risks related to their usage. Drugs of the chiral class have the drawback that only one of the two enantiomers may be active, while the other may be ineffective or have some negative effects. The inactive enantiomer can occasionally interact with the active enantiomer, lowering its potency or producing undesirable side effects. Additionally, Ibuprofen and other members of the chiral family of pharmaceuticals can interact with other drugs, including over-the-counter and prescription ones. To guarantee that only the active enantiomer is present in chiral-class medications, it is crucial for pharmaceutical companies to closely monitor their production and distribution processes. Lessening the toxicity or adverse effects linked to the inactive enantiomer, medical chemistry has recently seen an increase in the use of enantiomerically pure drugs. In any instance, the choice of whether to utilise a single enantiomer or a combination of enantiomers of a certain medicine should be based on clinical trial results and clinical competence. In addition to requests to determine and control the enantiomeric purity of the enantiomers from a racemic mixture, the use of single enantiomer drugs may result in simpler and more selective pharmacological profiles, improved therapeutic indices, simpler pharmacokinetics, and fewer drug interactions. Although, there have been instances where the wrong enantiomer results in unintended side effects, many medications are still used today as racemates with their associated side effects; this issue is probably brought on by both the difficulty of the chiral separation technique and the high cost of production. In conclusion, Ibuprofen and other medications in the chiral family, including those used to treat pain and inflammation, can be useful, but they also include a number of dangers and adverse effects. It's critical to follow a doctor's instructions when using these medications and to be aware of any possible interactions, allergic reactions, and other hazards. To maintain the security and efficacy of medicines in the chiral class, pharma producers also have a duty to closely monitor their creation and distribution. By Navnidhi Sharma Project Gallery