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An explanation of how cumulus clouds form and grow in the atmosphere Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link The physics behind cumulus clouds 14/07/25, 14:58 Last updated: Published: 07/10/23, 12:51 An explanation of how cumulus clouds form and grow in the atmosphere When you think of a cloud, it is most likely a cumulus cloud that pops into your head, with its distinct fluffy, cauliflower-like shape. The word ‘cumulus’ means ‘heaped’ in Latin, and aptly describes the clumpy shape of these detached clouds. They are one of the lowest clouds in the sky at altitudes of approximately 600 to 1000 metres, while the highest clouds form nearly 14 km up in the atmosphere. Depending on the position of the clouds in relation to the sun, they can appear in a brilliant white colour, or in a more foreboding grey colour. Cumulus clouds are classified into four different species: cumulus humilis clouds which are wider than they are tall, cumulus mediocris which have similar widths and heights, cumulus congestus which are taller than they are wide, and finally, cumulus fractus which have blurred edges as this is the cloud in its decaying form. Cumulus clouds are often associated with fair weather, with cumulus congestus being the only species that produces rain. So, how do cumulus clouds form, and why are they associated with fair weather? To understand the formation of these clouds, think of a sunny day. The sun shines on the land and causes surface heating. The warm surface heats the air above it which causes this air to rise in thermals, or convection currents. The air in the thermal expands and becomes less dense as it rises through surrounding cool air. The water vapour that is carried upwards in the convection current condenses when it gets cool enough and forms a cumulus cloud. Due to the varying properties of different surface types, some types are better at causing thermals than others. For example, the sun’s radiation will warm the surface of land more efficiently than the sea, leading to the formation of cumulus clouds over land rather than the sea. This is because water has a higher heat capacity than land, meaning it will take more heat to warm the water than the land. As cumulus clouds form on the top of independent thermals, they appear as individual floating puffs. But, what happens when cumulus clouds are knocked off the perch of their thermal by a breeze? How do they keep growing from an innocent, lazy cumulus humilis to a dark cumulus congestus, threatening rain showers? Latent heat gives us the answer. This is the energy that is absorbed, or released, by a body when it changes state. A cumulus cloud forms at the top of a thermal as the water molecules condense (changing state from a gas to a liquid) to form water droplets. When this happens, the warmth given off by the latent heat of condensation heats up the surrounding air causing it to expand and rise further, repeating the cycle and forming the characteristic cauliflower mounds of the cloud. The development of a cumulus humilis to cumulus congestus depends on the available moisture in the atmosphere, the strength of the sun’s radiation to form significant thermals, and whether there is a layer of warmer air higher up in the atmosphere that can halt the rising thermals. If the conditions are right, a cumulus congestus can keep growing and form a cumulonimbus cloud, which is an entirely different beast, more than deserving of its own article. So, the next time you see a cumulus cloud wandering through the sky, you will know how it came to be there. Written by Ailis Hankinson Related article: The physics of LIGO Project Gallery

The effect on sleep on nutrition (nutrition timing) Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link The interaction between circadian rhythms and nutrition Last updated: 27/04/25, 11:20 Published: 01/05/25, 07:00 The effect on sleep on nutrition (nutrition timing) The circadian system regulates numerous biological processes with roughly a 24-hour cycle, helping the organism adapt to the day-night rhythm. Among others, circadian rhythms regulate metabolism, energy expenditure, and sleep, for which meal timing is an excellent inducer. Evidence has shown that meal timing has a profound impact on health, gene expression, and lifespan. Proper timed feeding in accordance with the natural circadian rhythms of the body might improve metabolic health and reduce chronic disease risk. Circadian rhythms Circadian rhythms are controlled by the central clock of the brain, which coordinates biological functions with the light-dark cycle. Along with meal timing, circadian rhythms influence key elements of metabolism such as insulin sensitivity, fat storage, and glucose metabolism. When meal timing is not synchronised with the body's natural rhythm, it can cause circadian misalignment, disrupting metabolic processes and contributing to obesity, diabetes, and cardiovascular diseases. Literature has indicated that one should eat best during the daytime, particularly synchronised with the active phase of the body. Eating late at night or in the evening when the circadian rhythm of the body is directed towards sleep could impair metabolic function and lead to weight gain, insulin resistance, and numerous other diseases. Also, having larger meals in the morning and smaller meals later in the evening has been linked to improved metabolic health, sleep quality, and even lifespan. A time-restricted eating window, in which individuals eat all meals within a approximately 10–12 hour window, holds promise for improving human health outcomes like glucose metabolism, inflammation, harmful gene expression, and weight loss ( Figure 1 ). It is necessary to consider the impact of meal timing on gene expression. Our genes react to a number of stimuli, including environmental cues like food and light exposure. Gene expression of the body's metabolic, immune, and DNA repair processes are regulated by the body's circadian clock. Disturbances in meal timing influence the expression of these genes, which may result in greater susceptibility to diseases and reduced lifespan. Certain nutrients, such as melatonin in cherries and grapes, and magnesium in leafy greens and nuts, can improve sleep quality and circadian entrainment. Omega-3 fatty acids in fatty fish and flax seeds also have been shown to regulate circadian genes and improve metabolic functions. Other species Meal timing is quite varied among species, and animals have adapted such that food-seeking behavior is entrained into circadian rhythm and environmental time cues. There are nocturnal animals which eat at night, when they are active ( Figure 2 ). These nocturnal animals have evolved to align their meal time with their period of activity to maximise metabolic efficiency and lifespan. Meal timing is optimised in these animals for night activity and digestion. Humans, and most other animals, are diurnal and consume food during the day. In these animals, consuming most of their calories during the day is conducive to metabolic processes like glucose homeostasis and fat storage. These species tend to have better metabolic health when they are on a feeding regimen that is synchronized with the natural light-dark cycle. Conclusion Meal timing is important in human health, genetics, and life expectancy. Synchronising meal times with the body's circadian rhythms optimises metabolic function, reduces chronic disease incidence, and potentially increases longevity by reducing inflammatory genes and upregulating protective ones. This altered gene expression affects the way food is metabolised and metabolic signals are acted upon by the body. Humans naturally gravitate towards eating during daytime hours, while other creatures have feeding habits that are adaptively suited to their own distinct environmental needs. It is important to consider this science and incorporate it into our schedules to receive the best outcome from an activity that we do not normally think about. Written by B. Esfandyare Related article: The chronotypes REFERENCES Meléndez-Fernández, O.H., Liu, J.A. and Nelson, R.J. (2023). Circadian Rhythms Disrupted by Light at Night and Mistimed Food Intake Alter Hormonal Rhythms and Metabolism. International Journal of Molecular Sciences , [online] 24(4), p.3392. doi: https://doi.org/10.3390/ijms24043392 . Paoli, A., Tinsley, G., Bianco, A. and Moro, T. (2019). The Influence of Meal Frequency and Timing on Health in Humans: The Role of Fasting. Nutrients , [online] 11(4), p.719. Available at: https://www.ncbi.nlm.nih.gov/pubmed/30925707 . Potter, G.D.M., Cade, J.E., Grant, P.J. and Hardie, L.J. (2016). Nutrition and the circadian system. British Journal of Nutrition , [online] 116(3), pp.434–442. doi: https://doi.org/10.1017/s0007114516002117 . St-Onge MP, Ard J, Baskin ML, et al. Meal timing and frequency: implications for obesity prevention. Am J Lifestyle Med. 2017;11(1):7-16. Patterson RE, Sears DD. Metabolic effects of intermittent fasting. Annu Rev Nutr. 2017;37:371-393. Zhdanova IV, Wurtman RJ. Melatonin treatment for age-related insomnia. Endocrine. 2012;42(3):1-12. Prabhat, A., Batra, T. and Kumar, V. (2020). Effects of timed food availability on reproduction and metabolism in zebra finches: Molecular insights into homeostatic adaptation to food-restriction in diurnal vertebrates.Hormones and Behavior, 125, p.104820. Project Gallery

Natural substances and their treatment potential Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Using Natural Substances to Tackle Infectious Diseases 14/07/25, 15:11 Last updated: Published: 06/06/23, 17:06 Natural substances and their treatment potential Introduction There is increased concern of antimicrobial resistance, especially when referring to bacteria with superbugs such as Methicillin-resistant Staphylococcus aureus (MRSA) and Carbapenem-resistant Enterobacteriaceae (CRE) as they impact lives globally, mainly through fatalities. Given this predicament, It seems that humanity is losing as a result of this pressing issue. However, it is possible for healthcare professionals to utilise more natural products, which are chemicals made by plants, animals and even microorganisms. This includes resources such as wood and cotton aside from food like milk and cacao. In the context of medicinal treatments, an important justification for using more natural products is because although synthetic or partially synthetic drugs are effective for treating countless diseases, an article found that 8% of hospital admissions in the United States and approximately 100,000 fatalities per year were due to people experiencing unfortunate side effects from these drugs. This article explores three specific natural products, where each have similar and unique health properties that can be harnessed to tackle infectious diseases and its subsequent consequences when left sufficiently unaddressed (i.e. antimicrobial resistance). Honey One of the most famous natural products that has been referenced in various areas of research and has been a food and remedial source for thousands of years is honey. It has properties ranging from antibacterial to antioxidant, suggesting that when honey is applied clinically, they have the potential to stop pathogenic bacteria. For example, honey can protect the gastrointestinal system against Helicobacter pylori , which causes stomach ulcers. In disc diffusion assays, the inhibitive properties of honey were shown when honey samples were evaluated holistically as opposed to its individual ingredients. This implies that the macromolecules in honey (carbohydrates, proteins and lipids) work in unison with other biomolecules, illustrating that honey is a distinctive remedy for preventing bacterial growth. For tackling infectious diseases, particularly against wound infections among others, honey’s medicinal properties provide a lot of applications and because it is a natural product, honey would not present any drastic side effects to a patient upon its administration. Garlic Another natural product that can be effective against microorganisms is garlic because similar to honey, it has antimicrobial and antioxidative compounds. A study judged different garlic phenotypes originating from Greece and discovered that they were beneficial against Proteus mirabilis and Escherichia coli aside from inhibiting Candida albicans and C. kruzei . As for fresh garlic juice (FGJ), it increases the zone of inhibition in various pathogens at 10% and more along with it displaying minimum inhibitory concentrations (MICs) in the 4-16% range. Therefore, garlic in solid or liquid form does show potential as a natural antimicrobial agent, especially against pathogenic bacteria and fungi. With this in mind, it too has multiple applications like honey and should be further studied to best isolate the chemical compounds that could be involved in fighting infectious diseases. Turmeric Curcuma longa (also known as turmeric) is one other natural product with unique properties like garlic and honey, making it a suitable candidate against various microbes. One specific pigment that is part of the ginger family and found in turmeric is curcumin, which can tackle diverse microbes through numerous mechanisms illustrated below in Figure 2 . With this said, curcumin has drawbacks: it is highly hydrophobic, has low bioavailability and quickly breaks down. Although when paired with nanotechnology for delivery into the human body, its clinical applications can be advantageous and an additional observation about curcumin is that it can work collaboratively with other plant derived chemicals to stop antibiotic resistant bacteria. One specific bacterial strain that turmeric can attack is Clostridium difficile, a superbug that causes diarrhoea. A study had 27 strains to measure the MICs of turmeric constituents, particularly curcuminoids and curcumin. The results showed reduced C. difficile growth in the concentration range 4-32 μg/mL. Moreover, they had no negative impacts on the gut microbiome and curcumin had more efficacy in stopping C. difficile toxin production compared to fidaxomicin. Thus, turmeric is efficacious as a natural antimicrobial chemical and with further experimentation (same as honey and garlic), it can be harnessed to prevent infectious diseases besides their impact on human lives. Conclusion Considering the above examples of natural products in this article and others not mentioned, it is clear that they can be powerful in the battle against infectious diseases and the problems associated with them, mainly antimicrobial resistance. They are readily available to purchase in markets and shops at low cost, making them convenient. Moreover, populations in Eastern countries like China and India traditionally have used, and are still using these materials for curing pain and illness. In turn, manufacturing medicines from natural products on a larger scale has the prospect of preventing infectious diseases and even alleviating those that patients currently have. Written by Sam Jarada Related article: Mechanisms of pathogen evasion Project Gallery

An engineering case study Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Silicon hydrogel contact lenses 17/07/25, 11:08 Last updated: Published: 29/04/24, 10:59 An engineering case study Introduction Contact lenses have a rich and extensive history dating back over 500 years; when, in 1508, Leonardo Di Vinci first conceived the idea. It was not until the late 19th century that the concept of contact lenses as we know them now were realised. In 1887 F.E.Muller was credited with making the first eye covering that could improve vision without causing any irritation. This eventually led to the first generation of hydrogel-based lenses as the development of the polymer, hydroxyethyl methacrylate (HEMA), allowed Rishi Agarwal to conceive the idea of disposable soft contact lenses. Silicon hydrogel contact lenses dominate the contemporary market. Their superior properties have extended wear options and have transformed the landscape of vision correction. These small but complex items continue to evolve, benefiting wearers worldwide. This evolution is such that the most recent generation of silicon hydrogel lenses have recently been released and aim to phase out all the existing products. Benefits of silicon hydrogel lenses There are many benefits to this material’s use in this application. For example, the higher oxygen permeability improves user comfort and experience through relatively increased oxygen transmissibility that the material offers. These properties are furthered by the lens’ moisture retention which allows for longer wear times without compromising on comfort or eye health. Hence, silicon hydrogel lenses aimed to eradicate the drawbacks of traditional hydrogel lenses including: low oxygen permeability, lower lens flexibility and dehydration causing discomfort and long-term issues. This groundbreaking invention has revolutionised convenience and hygiene for users. The structure of silicon hydrogel lenses Lenses are fabricated from a blend of the two materials: silicon and hydrogel. The silicon component provides high oxygen permeability, while the hydrogel component contributes to comfort and flexibility. Silicon is a synthetic polymer and is inherently oxygen-permeable; it facilitates more oxygen to reach the cornea, promoting eye health and avoiding hypoxia-related symptoms. Its polymer chains form a network, creating pathways for oxygen diffusion. Whereas hydrogel materials are hydrophilic polymers that retain water, keeping the lens moist and comfortable as it contributes to the lens’s flexibility and wettability. Both materials are combined using cross-linking techniques which stabilise the matrix to make the most of both properties and prevent dissolution. (See Figure 1 ). There are two forms of cross-linking that enable the production of silicon hydrogel lenses: chemical and physical. Chemical cross-linking involves covalent bonds between polymer chains, enhancing the lens’s mechanical properties and stability. Additionally, physical cross-links include ionic interactions, hydrogen bonding, and crystallisation. Both techniques contribute to the lens’s structure and properties and can be enhanced with polymer modifications. In fact, silicon hydrogel macromolecules have been modified to optimise properties such as: improved miscibility with hydrophilic components, clinical performance and wettability. The new generation of silicon hydrogel contact lenses Properties Studies show that wearers of silicon hydrogel lenses report higher comfort levels throughout the day and at the end of the day compared to conventional hydrogel lenses. This is attributed to the fact that they allow around 5 times more oxygen to reach the cornea. This is significant as reduced oxygen supply can lead to dryness, redness, blurred vision, discomfort, and even corneal swelling. What’s more, the most recent generation of lenses have further improved material properties, the first of which is enhanced durability and wear resistance. This is attributed to their complex and unique material composition, maintaining their shape and making them suitable for various lens designs. Additionally, they exhibit a balance between hydrophilic and hydrophobic properties which have traditionally caused an issue with surface wettability. This generation of products have overcome this through surface modifications improving comfort by way of improving wettability. Not only this, but silicon hydrogel materials attract relatively fewer protein deposits. Reduced protein buildup leads to better comfort and less frequent lens replacement. Manufacturing There are currently two key manufacturing processes that silicon hydrogel materials are made with. Most current silicon hydrogel lenses are produced using either cast moulding or lathe cutting techniques. In lathe cutting, the material is polymerised into solid rods, which are then cut into buttons for further processing in computerised lathe - creating the lenses. Furthermore, surface modifications are employed to enhance this concept. For example, plasma surface treatments enhance biocompatibility and improve surface wettability compared to earlier silicon elastomer lenses. Future innovations There are various future expansions related to this material and this application. Currently, researchers are exploring ways to create customised and personalised lenses tailored to an individual’s unique eye shape, prescription, and lifestyle. One of the ways they are aiming to do this is by using 3D printing and digital scanning to allow for precise fitting. Although this is feasible, there are some challenges relating to scalability and cost-effectiveness while ensuring quality. Moreover, another possible expansion is smart contact lenses which aim to go beyond just improving the user's vision. For example, smart lenses are currently being developed for glucose and intraocular pressure monitoring to benefit patients with diseases including diabetes and glaucoma respectively. The challenges associated with this idea are data transfer, oxygen permeability and therefore comfort. (See Figure 2 ). Conclusion In conclusion, silicon hydrogel lenses represent a remarkable fusion of material science and engineering. Their positive impact on eye health, comfort, and vision correction continues to evolve. As research progresses, we can look forward to even more innovative solutions benefiting visually-impaired individuals worldwide. Written by Roshan Gill Related articles: Semi-conductor manufacturing / Room-temperature superconductor / Titan Submersible / Nanogels REFERENCES Optical Society of India, Journal of Optics, Volume 53, Issue 1, Springer, 2024 February Lamb J, Bowden T. The history of contact lenses. Contact lenses. 2019 Jan 1:2-17. Ţălu Ş, Ţălu M, Giovanzana S, Shah RD. A brief history of contact lenses. Human and Veterinary Medicine. 2011 Jun 1;3(1):33-7. Brennan NA. Beyond flux: total corneal oxygen consumption as an index of corneal oxygenation during contact lens wear. Optometry and vision science. 2005 Jun 1;82(6):467-72. Dumbleton K, Woods C, Jones L, Fonn D, Sarwer DB. Patient and practitioner compliance with silicon hydrogel and daily disposable lens replacement in the United States. Eye & Contact Lens. 2009 Jul 1;35(4):164-71. Nichols JJ, Sinnott LT. Tear film, contact lens, and patient-related factors associated with contact lens–related dry eye. Investigative ophthalmology & visual science. 2006 Apr 1;47(4):1319-28. Jacinto S. Rubido, Ocular response to silicone-hydrogel contact lenses, 2004. Musgrave CS, Fang F. Contact lens materials: a materials science perspective. Materials. 2019 Jan 14;12(2):261. Shaker LM, Al-Amiery A, Takriff MS, Wan Isahak WN, Mahdi AS, Al-Azzawi WK. The future of vision: a review of electronic contact lenses technology. ACS Photonics. 2023 Jun 12;10(6):1671-86. Kim J, Cha E, Park JU. Recent advances in smart contact lenses. Advanced Materials Technologies. 2020 Jan;5(1):1900728. Project Gallery

The lunar terrain Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link A love letter from outer space: Lonar Lake, India Last updated: 09/10/25, 10:05 Published: 10/04/25, 07:00 The lunar terrain Around 50,000 years ago, outer space gifted the earth with a crater that formed the foundations of the world’s third largest natural saltwater lake, situated within a flat volcanic area known as the Deccan Plateau. This resulted from a 2 million tonne meteorite tunnelling through the earth’s atmosphere at the velocity of 90,000km/hour and colliding into the Deccan Plateau. As time slipped away, pressure and heat melted the basalt rock tucked underneath the impact, and the accumulation of rainwater filled the crater with water. These foundations curated what is famously known today as the ‘Lonar Lake’. What is unique about the Lonar Lake is that it is the only meteorite-crater formed in basaltic terrain - synonymous to a lunar terrain. Additionally, the remnants bear similarities to the terrestrial composition of Mercury, which contains craters, basaltic rock and smooth plains resulting from volcanic activity. Many speculations have arisen to prove the theory of the crater forming from the impact of a meteorite. One such collaborative study conducted by The Smithsonian Institute of Washington D.C. USA, the Geological Survey of India and the US Geological Survey involved drilling holes at the bottom of the crater and scrutinising the compositions of rock samples sourced from the mining. When tested in the laboratory, it was found that the rock samples contained leftovers of the basaltic rock that were modified from the crater collision under high heat and pressure. In addition, shattered cone-shaped fractures, due to high velocity shock waves being transmitted into the rocks, were identified. These two observations align with the meteorite impact phenomenon. Additionally, along with its fascinating astronomical properties, scientists have been intrigued by the chemical composition of the lake within the crater. Its dark green colour results from the presence of the blue-green algae Spirulina. The water also has a pH of 10, making the water alkaline in nature, supporting the development of marine systems. One explanation for the alkalinity of the water is that it is a result of immediate sulphide formation, where the groundwater of meteorite origin contains CO2 undergoes a precipitation reaction with alkaline ions, leaving a carbonate precipitate with an alkaline nature. What is also striking about the composition of the water as well is its saline nature, which coexists with the alkaline environment - a rare phenomenon to occur in ecological sciences. The conception of the lake, from the matrimony of Earth with the debris within outer space, has left its imprints within the physical world. It's a love letter, written in basaltic stone and saline water, fostering innovation in ecology. The inscription of the meteorite’s journey within the crater has branched two opposing worlds, one originating millions of miles away from humans with one that resides in the natural grounds of our souls. Written by Shiksha Teeluck Related articles: Are aliens on Earth? / JWST / The celestial blueprint of time: Stonehenge REFERENCES Taiwade, V. S. (1995). A study of Lonar lake—a meteorite-impact crater in basalt rock. Bulletin of the Astronomical Society of India, 23, 105–111. Tambekar, D. H., Pawar, A. L., & Dudhane, M. N. (2010). Lonar Lake water: Past and present. Nature Environment and Pollution Technology, 9(2), 217–221. Project Gallery

Contributions include artificial radioactive atoms, atomic structure, ribosome research Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Female Nobel Prize Winners in Chemistry 02/05/25, 11:30 Last updated: Published: 03/06/23, 17:37 Contributions include artificial radioactive atoms, atomic structure, ribosome research Women contributing their innovative ideas has strengthened the knowledge held in the scientific world. It is important to realise that women in STEM need to be celebrated all year round – they need to be given the recognition they deserve. A total of 60 women have been awarded the Nobel Prize between 1901 and 2022. Specifically looking at the Female Nobel Prize winners in Chemistry – all of whom have changed the way society views women but also puts a spotlight on the progress that can still be made if we have more women in the field of STEM. There have been eight women to receive this prestigious award: Carolyn R. Bertozzi, Emmanuelle Charpentier, Jennifer A. Doudna, Frances H. Arnold, Ada E., Dorothy Crowfoot Hodgkin, Yonath, Irène Joliot-Curie and Marie Curie. This article celebrates their ground-breaking discoveries and contributions to the world of science and is a way to serve as an inspiration to young girls and women in the hope to raise a generation where more women are studying STEM subjects and acquiring high-ranked roles to reduce the gender gap. Nobel Prizes won in- 2022: Carolyn R. Bertozzi was awarded for her development of biorthogonal reactions which has allowed scientists to explore and track biological processes without disrupting the chemistry of the original cells. 2020: Emmanuelle Charpentier and Jennifer Doudna were awarded for their development of a method for high-precision genome editing: CRISPR/Cas9 genetic scissors. They used the immune system of a bacterium, which disables viruses by cutting their DNA up with a type of genetic scissors. The CRISPR/Cas9 genetic scissors has led to many exciting discoveries and new ways to fight against cancer and genetic diseases. 2018: Frances Arnold was awarded because of her work on directed evolution of enzymes. In 1993, Arnold conducted the first directed evolution of enzymes, which are proteins that catalyse chemical reactions. This has led to the manufacturing of environmentally friendly chemical substances such as pharmaceuticals, and the production of renewable fuels. 2009: Ada Yonath was awarded the Nobel Prize for her studies on the structure and functions of the ribosome. In the 1970s, Ada began a project that concluded in her successful mapping of the structure of ribosomes, which consisted of thousands of atoms, using x-ray crystallography. This has been important in the production of antibiotics. 1964: Dorothy Hodgkin was awarded the 1964 Nobel Prize in Chemistry for solving the atomic structure of molecules such as penicillin and insulin, using X-ray crystallography. 1935: Irène Joliot-Curie was awarded for her discovery that radioactive atoms could be created artificially. Written by Khushleen Kaur Related articles: Female Nobel prize winners in physics / African-American women in cancer research Project Gallery

Beavers alter their landscape through dams, canals, and felling trees Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Beavers are back in Britain, ‘wood’ you like to know why? 09/07/25, 10:58 Last updated: Published: 03/12/24, 12:05 Beavers alter their landscape through dams, canals, and felling trees This is article no. 3 in a series on animal conservation. Next article: Pangolins: from poached to protected . Previous article: Conserving the California condor Eurasian beavers ( Castor fiber ) transform freshwater habitats so dramatically that they are nicknamed ‘ecosystem engineers’. Their dam-building and tree-felling activities could reduce flood risk and increase biodiversity. After being hunted to extinction centuries ago, beavers have been reintroduced to Britain in both organised and illicit ways. This article will describe where they have been reintroduced in Britain, and the impact they could have. Ecological importance of beavers By building dams, Eurasian beavers alter their habitat - often for the better. Beaver dams are made from wood, stones, and mud. They control the flow of river water, reducing the risk of floods and droughts. The resulting slower water is a good place for amphibians to lay eggs and undergo the aquatic part of their life cycle. As water builds up behind the dam, it converts the area into a wetland - a source of drinking water for animals like bats and an excellent carbon sink. Meanwhile, invertebrates can lay eggs or hide from predators in the spaces within beaver dams ( Figure 1 ). Further up the food chain, beaver dams have complex effects on fish. Although the still water provides habitat for overwintering and rearing young, dams restrict the movement of fish species like salmon. However, most studies have concluded that beaver dams benefit freshwater biodiversity. Dams are not the only way Eurasian beavers improve their landscape. To access food and construction materials easily, beavers dig canals – which make the habitat better drained and more complex. Moreover, beavers gnaw at tree trunks and branches, sometimes knocking over entire trees. This creates deadwood where terrestrial invertebrates can live. Felling trees also allow sunlight to reach the river surface, promoting aquatic plant growth. When beavers gnaw at willow trees, they create propagules, which disperse along the beaver-made canal network and grow downstream. These new willow trees stabilise the river bank and further reduce the flood risk. Humans often trim back trees to stimulate their growth – called coppicing – but beavers do this free of charge. Coppicing, dam building, and canal digging are just a few ways beavers save the human costs of restoring and protecting natural habitats. Extinction and reintroduction However, Eurasian beavers used to be more exploited than appreciated. They were hunted for their fur, meat, and a secretion called castoreum, which is used in perfume and pharmaceuticals. Exactly when and how the beaver population went extinct from Britain is unclear, but the last written record of a beaver is from 1526 in Scotland and 1780 in England. Since then, the British turned wetlands into farmland and forgot about beavers … until recently. After centuries, beavers returned to Scotland in the late 2000s. A handful of beavers were spotted in River Tay about 15 years ago, after either an enclosure escape or an illegal release. There are 114 families in this illegal population, which has genetic origins in Germany. The first official beaver reintroduction occurred in Knapdale Forest, Scotland, in 2009 – but this population did not grow as quickly as the River Tay one. With scepticism, the reintroduction of Eurasian beavers to Scotland was deemed a success, and they became a ‘European Protected Species’ in Scotland in 2019. Seeing Eurasian beavers thriving in Scotland encouraged reintroduction plans in England. In the English county of Devon, River Otter showed signs of beaver presence since 2008 and breeding since 2013. Authorities were worried these illegally released beavers would spread foreign diseases to local wildlife, but the public campaigned to let the beavers be. Public affection for beavers led to the River Otter Beaver Trial in 2015, where two breeding pairs were released into the river after thorough health checks. By 2019, the number of breeding pairs grew to seven ( Figure 2 ). Therefore, beavers have successfully returned to England. Conclusion Beavers alter their landscape through dams, canals, and felling trees. However, in Britain, they were hunted to extinction a long time ago. Although beavers first returned to England and Scotland illegally, they now live in healthy, growing populations. Hopefully they will remain protected and loved by the public, helping us to restore wetlands and improve British freshwater biodiversity. Written by Simran Patel Related article: Vicuna conservation REFERENCES Andersen, L.H. et al. (2023) ‘Can reintroduction of beavers improve insect biodiversity?’, Journal of Environmental Management , 337, p. 117719. Available at: https://doi.org/10.1016/j.jenvman.2023.117719 . Brazier, R.E., Elliott, M., Andison, E., Auster, R.E., Bridgewater, S., Burgess, P., Chant, J., Graham, H., Knott, E., Puttock, A.K., Sansum, P., Vowles, A., (2020) ‘River Otter Beaver Trial: Science and Evidence Report’. Brazier, R.E. et al. (2021) ‘Beaver: Nature’s ecosystem engineers’, WIREs Water , 8(1), p. e1494. Available at: https://doi.org/10.1002/wat2.1494 . Campbell-Palmer, R. et al. (2020) ‘Beaver genetic surveillance in Britain’, Global Ecology and Conservation , 24, p. e01275. Available at: https://doi.org/10.1016/j.gecco.2020.e01275 . Gaywood, M., Batty, D. and Galbraith, C. (2008) ‘Reintroducing the European Beaver in Britain’, British Wildlife , 19, pp. 381–391. Halley, D.J., Saveljev, A.P. and Rosell, F. (2021) ‘Population and distribution of beavers Castor fiber and Castor canadensis in Eurasia’, Mammal Review , 51(1), pp. 1–24. Available at: https://doi.org/10.1111/mam.12216 . Hooker, J. et al. (2024) ‘Re-establishing historic ecosystem links through targeted species reintroduction: Beaver-mediated wetlands support increased bat activity’, Science of The Total Environment , 951, p. 175661. Available at: https://doi.org/10.1016/j.scitotenv.2024.175661 . Wilson, J.B., Bradley, J. and Bremner-Harrison, S. (2024) ‘The short-term impact of Eurasian beavers ( Castor fiber ) post-reintroduction on amphibian abundance and diversity in a lentic environment’, The Glasgow Naturalist , 28(2). Available at: https://doi.org/10.37208/tgn28224 . Project Gallery

Applications of ancient DNA analysis Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Are aliens on Earth? 09/07/25, 10:52 Last updated: Published: 04/10/23, 17:13 Applications of ancient DNA analysis During a recent congressional hearing regarding UFOs held by Mexico, two alleged alien corpses were presented by UFO enthusiast Jaime Maussan. These artefacts were met with scepticism due to Maussan’s previous five claims to have found aliens, all debunked as mummified human remains. To verify the newly found remains as alien, various lab tests have been performed, one being a carbon-14 analysis by researchers at the Autonomous National University of Mexico. This analysis estimated the corpses to be approximately 1000 years old. Determination of the corpses’ genetic make-up is another essential technique for the verification of the supposed alien remains, but is it possible for these ancient remains to undergo DNA analysis? Yes; in fact, there are methods specialised for cases such as these that enable ancient DNA (aDNA) analysis. The relatively recent advent of high throughput sequencing technology has streamlined DNA sequencing into becoming a more rapid and inexpensive process. However, aDNA has fundamental qualities that complicate its analysis such as postmortem damage, extraneous co-extracted DNA and the presence of other contaminants. Therefore, extra steps are essential in the bioinformatics workflow to make sure that the aDNA is sequenced and analysed as accurately as possible. So, let’s talk about the importance of aDNA analysis in various areas and how looking at the genetics of the past, and potentially space, can unearth information for modern research. Applications of aDNA sequencing and analysis Analysis of ancient DNA is a useful technique for the discovery of human migration events from hundreds of centuries ago. For example, analyses of mitochondrial DNA (mtDNA) have repeatedly substantiated the “Recent African Origin” theory of modern human origins; the most common ancestor of human mtDNA was found to exist in Africa about 100,000-200,000 years ago. There have also been other recent studies within phylogeography; an aDNA study on skeletal remains of ancient northwestern Europeans carried out in 2022 showed that mediaeval society in England was likely the result of mass migration across the North Sea from the Netherlands, Germany and Denmark. Thus, these phylogeographic discoveries improve our knowledge of the historic evolution and migration of human populations. Paleopathology, the study of disease in antiquity, is another area for which ancient DNA analysis is important. Analysis of DNA from the victims of the Plague of Justinian and the Black Death facilitated the identification of Yersinia Pestis and determined it as the causal agent in these pandemics. The contribution of aDNA analysis is consequently important to reveal how diseases have affected past populations and this derived genetic information can be used to identify their prevalence in modern society. Exciting yet debatably ethical plans for the de-extinction of species have also been announced. The biotech company Colossal announced plans in 2021 to resurrect the woolly mammoth among other species such as the Tasmanian tiger and the dodo bird. Other groups plan to resurrect the Christmas Island rat and Steller’s sea cow. In theory, this is exciting, or scary from certain ecological perspectives, but is complicated in practice. Even though the number of nuclear genomes sequenced from extinct species exceeds 20, there has been no restoration of species to date. Are aliens on Earth? Thus, ancient DNA analysis can be applied to a multitude of areas to give historical information that we are able to carry into the modern world. But, finally, are these ‘alien’ corpses legitimately from outer space? José Zalce Benitez is the director of the Health Sciences Research Institute in the secretary of the Mexican Navy’s office and he reports on the scientists’ findings. The DNA tests were allegedly compared with over one million species and found not to be genetically related to “what is known or described up to this moment by science.” In essence, genetic testing has not conflicted with Maussan’s claim that these remains are alien so the possibility of their alien identity cannot yet be dismissed. However, this genetic testing does not appear to be peer-reviewed; NASA is reportedly interested in the DNA analysis of these corpses, so we await further findings. Ancient DNA analysis will undoubtedly provide intriguing information about life from outer space or, alternatively, how this DNA code was faked. Whatever the outcome, ancient DNA analysis remains an exciting area of research about life preceding us. Written by Isobel Cunningham Related article: Astro-geology of Lonar Lake Project Gallery

What they are, uses, and future outlook Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Advancements in Semiconductor Laser Technology 08/07/25, 16:19 Last updated: Published: 23/06/24, 09:39 What they are, uses, and future outlook Lasers have revolutionised many fields starting from the telecommunications, data storage to medical diagnostics and consumer electronics. And among the semiconductor laser technologies, Edge Emitting Lasers (EEL) and Vertical Cavity Surface Emitting Lasers (VCSEL) emerged as critical components due to their unique properties and performance. These lasers generate light through the recombination of electrons and holes in a semiconductor material. EELs are known for their high power and efficiency and they are extensively used in fiber optic communications and laser printing. VCSELs on the other hand are compact and are used for applications like 3D sensing. Traditionally VCSELs have struggled to match the efficiency levels of EELs however a recent breakthrough particularly in multi junction VCSEL, has demonstrated remarkable efficiency improvements which place the VCSELs to surpass EELs in various applications. This article focuses on the basics of these laser technologies and their recent advancements. EELs are a type of laser where light is emitted from the edge of the semiconductor wafer. This design contrasts with the VCSELs which emit light perpendicular to the wafer surface. EELs are known for their high power output and efficiency which makes them particularly suitable for applications that require long-distance light transmission such as fiber optic communications, laser printing and industrial machining. EELs consist of an active region where electron hole recombination occurs to produce light. This region is sandwiched between two mirrors forming a resonant optical cavity. The emitted light travels parallel to the plane of the semiconductor layers and exits from the edge of the device. This design allows EELs to achieve high gain and power output which makes them effective for transmitting light over long distances with minimal loss. VCSELs are a type of semiconductor laser that emits light perpendicular to the surface of the semiconductor wafer unlike the EELs which emit light from the edge. VCSELs have gained popularity due to their lower threshold currents and ability to form high density arrays. VCSELs consist of an active region where electron-hole recombination occurs to produce light. This region is situated between two highly reflective mirrors which forms a vertical resonant optical cavity. The light is emitted perpendicular to the wafer surface which allows for efficient vertical emission and easy integration into arrays. Recent advancements in VCSEL technology marked a significant milestone in the field of semiconductor lasers. And in particular the development of multi junction VCSEL which led to the improvements in power conversion efficiency (PCE) of the laser. Research conducted by Yao Xiao et al. and team has demonstrated the potential of a multi junction VCSELs to achieve efficiency levels which were previously thought unattainable. This research focuses on cascading multiple active regions within a single VCSEL to enhance gain and reduce threshold current which leads to higher overall efficiency. The study employed a multi-junction design where several active regions are stacked vertically within the VCSEL. This design increases the volume of the gain region and lowers the threshold current density resulting in higher efficiency. Experimental results from the study revealed that a 15-junction VCSEL achieved a PCE of 74% at room temperature when driven by nanosecond pulses. This efficiency is the highest ever reported for VCSELs and represents a significant leap forward from previous records. Simulations conducted as part of the study indicated that a 20-junction VCSEL could potentially reach a PCE exceeding 88% at room temperature. This suggests that further optimization and refinement of the multi-junction approach could yield even greater efficiencies. The implications of this research are profound for the future of VCSEL technology. Achieving such high efficiencies places VCSELs as strong competitors to EELs particularly in applications where energy efficiency and power density are critical. The multi junction VCSELs demonstrated in the study shows promise for a wide range of applications and future works may focus on optimizing the fabrication process, reducing thermal management issues and exploring new materials to further enhance performance. Integrating these high-efficiency VCSELs into commercial products could revolutionize industries reliant on laser technology. Written by Arun Sreeraj Related articles: The future of semi-conductor manufacturing / The search for a room-temperature superconductor / Advances in mass spectrometry Project Gallery

The future of precision healthcare: nanocarriers Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Nanomedicine and targeted drug delivery Last updated: 17/07/25, 10:53 Published: 17/07/25, 07:00 The future of precision healthcare: nanocarriers In recent years, nanomedicine - the application of nanotechnology in healthcare - has emerged as a powerful and versatile area of research and is rapidly developing with many promising opportunities in the medical sciences. Nanocarriers are being developed for pharmaceuticals for example, with uses in cancer treatment and in particular targeted drug delivery. In nanomedicine, the materials are engineered at the nanoscale, with sizes ranging from 100 to 1000 nm, and can be used to perform specific biomedical tasks. These nanomaterials, such as nanoparticles, are often made from crosslinked polymer chains and can encapsulate therapeutic molecules for delivery within the body. Their small sizes give them unique properties, as they can interact with cells at a molecular level, and be designed to respond at specific times and locations, which can be directed to specific tissues or environments. Since the coronavirus disease (COVID-19) pandemic, nanoparticle-based drug delivery platforms have been widely studied - lipid nanoparticles were used in the vaccine to combat the virus. Being highly successful, and looking ahead, research and development in nanomedicine-based drug delivery is expected to keep growing, as the interest in more precise and effective treatments continues to rise. How can nanoparticles be used for drug delivery? A significant challenge in conventional drug therapies lies in their limited solubility, which can reduce the effectiveness of a drug and cause harmful side effects. Nanoparticles offer a solution to this: they can encapsulate poorly soluble drugs, protecting them from degradation in the body, and this allows them to be carried safely to the targeted tissues. This localised delivery improves the drugs’ biodistribution, and reduces systemic toxicity, which is a common concern in treatments such as chemotherapy, where healthy tissues in the body are damaged. Nanoparticles in particular are exciting as they have tuneable surface properties and a high surface to area volume ratio. This means their physical and chemical behaviours can be adjusted - for example through changing their sizes, shapes, or surface chemistries - to match a specific medical application or target. In addition to this, nanoparticles undergo the enhanced permeability and retention (EPR) effect; a phenomenon where they naturally accumulate in tumour tissues due to the leaky nature of tumour blood vessels. This effect improves the targeting precision, and drugs can be delivered more efficiently to cancer cells, while sparing healthy ones one, avoiding unnecessary damage and side effects to the patient. While drug delivery is a major focus, nanomedicine research also plays a role in diagnostics. Nanoparticles can be engineered to function as contrast agents in medical imaging, helping doctors detect diseases earlier and monitor treatments more accurately. There is also a growing interest in using nanomaterials for tissue regeneration, by creating scaffolds that support the repair and regrowth of damaged tissues. As research continues, nanomedicine holds promise for tacking some of the most pressing challenges in modern healthcare - from treating cancer more safely to developing new vaccines and personalised therapies. Though there are some hurdles, particularly around large-scale manufacturing and regularly approval, the path ahead for nanomedicine has huge potential. As the field of nanomedicine continues to grow, it shows great promise in reshaping healthcare with treatments that are smarter, safer, and more effective - ultimately improving patient outcomes and transforming the way we fight disease. Written by Saanchi Agarwal Related articles: Nanomedicine / Nanoparticles and diabetes treatment / Nanoparticles and health / Nanogels Project Gallery