Category: The Conversation

Source: The Conversation – UK – By Aleh Cherp, Professor, Department of Environmental Sciences and Policy, Central European University

Just 1% of the world’s coastal waters could, in theory, generate enough offshore wind and solar power to provide a third of the world’s electricity by 2050. That’s the promise highlighted in a new study by a team of scientists in Singapore and China, who systematically mapped the global potential of renewables at sea.

But turning that potential into reality is another story. Scaling up offshore renewables fast enough to seriously dent global emissions faces formidable technical, economic and political hurdles.

To reach global climate targets, the world’s electricity systems must be fully decarbonised within a couple of decades if not sooner. Wind and solar power have grown at record-breaking rates, yet further expansion on land is increasingly constrained by a scarcity of good sites and conflicts over land use.

Moving renewables offshore is therefore tempting. The sea is vast, windy and sunny, with few residents around to object. The team behind the new study identified coastal areas with enough wind or sunlight, and water shallower than 200 metres, that are relatively ice-free and within 200 kilometres of population centres.

They estimate that using just 1% of these areas could generate over 6,000 terawatt hours (TWh) of offshore wind power and 14,000TWh of offshore solar power each year. Together that’s roughly one-third of the electricity the world is expected to use in 2050, while avoiding 9 billion tonnes of CO₂ annually.

That sounds impressive as 1% of suitable ocean seems small. Many European countries, such as Denmark, Germany, Belgium and the UK, already allocate between 7% and 16% of their coastal waters for offshore wind farms. Yet what matters for climate mitigation is not only how much low-carbon energy could eventually be produced, but how fast that could happen.

At present, offshore wind generates less than 200TWh per year, less than 1% of global electricity. By 2030, that might rise to around 900TWh. Hitting 6,000TWh by 2050 would require annual installations – each year, for two decades – to be about seven times larger than they were last year.

Offshore solar requires an even steeper climb. The technology is still experimental, producing only negligible amounts of electricity today.

Even if 15TWh a year (an equivalent of some 15GW capacity) can be generated by 2030, to reach the estimated potential of 14,000TWh by 2050 would require sustained annual growth of over 40% for two decades. Such a rate that has never been achieved for any energy technology, not even during the recent record-breaking growth of land solar.

Achieving techno-economic viability

Around 90% of existing offshore wind capacity is located in the shallow, sheltered waters of northwestern Europe and China, where most turbines are directly fixed to the seabed. Yet most of the untapped potential lies in deeper waters, where fixed foundations are impossible.

That means turning to floating turbines, a technology that currently accounts for just 0.3% of global offshore wind capacity. Floating wind power faces serious engineering challenges, from mooring and anchoring, to undersea cabling and maintenance in rougher seas.

It currently costs far more than fixed-bottom systems, and will need substantial subsidies for at least the next decade. Only if early projects prove successful and drive down costs could floating wind become commercially viable.

Offshore solar is even further behind. The International Energy Agency rates its technology readiness at only level three to five on an 11-point scale — barely beyond prototype stage. The new study refers to research saying offshore solar could become commercially viable in the Netherlands only around 2040-2050, by which time the world’s power system should already be largely decarbonised.

Overcoming growth barriers

Even when low-carbon technologies become commercially competitive, their growth rarely continues exponentially. Our own research shows manufacturing bottlenecks, logistics and grid integration eventually slow expansion. And these challenges are likely to be even tougher for offshore projects.

Social opposition and the need for permits can also slow progress. Moving wind and solar offshore avoids some land-use conflicts, but it does not eliminate them. Coastal space close to populated areas is already crowded with shipping, fishing, leisure and military activities.

In Europe, approval and construction of offshore wind farms can a decade or more. Permits are not guaranteed: Sweden recently rejected 13 proposed wind farms in the Baltic Sea due to national security concerns.

What is realistic?

Offshore renewables will undoubtedly play an important role in the global energy transition. Offshore wind, in particular, could become a major contributor by mid-century if its growth follows the same trajectory as onshore wind has since the early 2000s.

However, that would require floating turbines to quickly become competitive, and for political commitment to be secured in the Americas, Australia, Russia and other areas with lots of growth potential.

Offshore wind (green) is tracking the growth rate of onshore wind (orange):

Offshore solar, by contrast, would need to achieve viability and then grow at an unprecedented rate to reach the potential outlined in the new study. It may be promising for niche uses, but is unlikely to deliver large-scale climate benefits before 2050.

Its real contribution may come later in the century, when we will still need to expand low-carbon energy for industries, transport and heating once the initial decarbonisation of power generation is complete.

For now, the world’s best bet remains to accelerate onshore wind and solar power as well as proven offshore wind technologies, while preparing offshore solar and floating wind power options for the longer run.

Aleh Cherp receives funding from Swedish Foundation for Strategic Environmental Research (MISTRA) and Swedish Energy Agency.

Jessica Jewell receives funding from the European Union’s H2020 ERC Starting Grant programme under grant agreement no. 950408 project Mechanisms and Actors of Feasible Energy Transitions (MANIFEST), Mistra Environmental Research (MISTRA), and the Swedish Energy Agency.

Tsimafei Kazlou receives funding from the European Union’s H2020 ERC Starting Grant programme under grant agreement no. 950408 project Mechanisms and Actors of Feasible Energy Transitions (MANIFEST).

– ref. Just 1% of coastal waters could power a third of the world’s electricity – but can we do it in time? – https://theconversation.com/just-1-of-coastal-waters-could-power-a-third-of-the-worlds-electricity-but-can-we-do-it-in-time-268237

Source: The Conversation – UK – By Kate Spencer, Professor of Environmental Geochemistry, Queen Mary University of London

Think of ocean plastic and you may picture bottles and bags bobbing on the waves, slowly drifting out to sea. Yet the reality is more complex and far more persistent.

Even if we stopped all plastic pollution today, our new research shows that fragments of buoyant plastic would continue to pollute the ocean’s surface for more than a century. These fragments break down slowly, releasing microplastics that sink through the water column at a glacial pace. The result is a “natural conveyor belt” of pollution that links the surface to the deep sea.

Our new study set out to understand what happens to large pieces of floating plastic once they enter the ocean. We developed a computer model to simulate how these plastics degrade, fragment and interact with the sticky suspended particles known as “marine snow” which help transport matter to the seafloor.

Marine snow is the ocean’s natural snowfall: tiny, sticky flakes of dead plankton and other organic particles that clump together and slowly sink, carrying anything that sticks, like microplastics, down into the deep.

The new model builds on our previous work understanding the long-term fate of microplastics smaller than 1mm, which showed that plastics would only interact with suspended fine organic particles once they had broken down and reached a critical size threshold. But that simple one-dimensional model didn’t consider other physical processes, such as ocean currents.

By linking plastic degradation to ocean processes including marine snow settling, we have now provided a more complete picture of how small plastic particles move through the ocean system, and why some floating plastic appears to vanish from the surface.

The ‘missing plastic’ problem

When large plastics such as food wrappers or fragments of fishing gear reach the ocean, they can remain afloat for years, slowly battered by sunlight and waves and colonised by marine biofilm – microbial communities that live on the plastic surface.

Over time, they break into smaller and smaller pieces, eventually becoming small enough to attach to marine snow and sink. But this is a slow transformation. After 100 years, around 10% of the original material can still be found at the ocean’s surface.

Read more:
We’re witnessing last-ditch talks to secure a global plastic pollution treaty

As for the rest, scientists have long noticed a puzzling mismatch between the amount of plastic entering the ocean and the much smaller quantities found floating at the surface. Floating plastics must be removed from the ocean’s surface layer through degradation and sinking, but so far the numbers have not quite added up. Our findings help explain this “missing plastic” problem.

We are not the first scientists to report the sinking of microplastics. But by combining experimental work on how microplastics associate with fine suspended sediments, with our modelling of plastic degradation and marine snow settling processes, we provide realistic estimates of how microplastics are removed from the ocean surface which account for the missing plastic.

The ocean’s natural biological pump, often described as a conveyor belt, moves carbon and nutrients from the surface to the deep sea. Our research suggests this same process also moves plastics.

However, there is a potential cost. As global plastic production continues to rise, the biological pump could become overloaded. If too many microplastics attach to marine snow, they may interfere with how efficiently the ocean stores carbon – an effect that could have consequences for marine ecosystems and even climate regulation.

A conveyor belt for pollution

Microplastic pollution is not a short-term problem. Even if we achieved zero plastic waste today, the ocean’s surface would remain contaminated for decades.

To tackle the problem effectively, we need long-term thinking, not just beach or ocean cleanups. Policies need to address plastic production, use and disposal at every stage. Understanding how plastic moves through the ocean system is a crucial step towards that goal.

Read more:
‘Everywhere we looked we found evidence’: the godfather of microplastics on 20 years of pollution research and the fight for global action

Large, buoyant plastic items degrade over decades, shedding microplastics as they go. These tiny fragments may eventually sink to the ocean floor, but only after going through multiple cycles of attachment and release from marine snow, a process that can take generations.

This means plastics lost at sea decades ago are still breaking down today, creating a persistent source of new microplastics.

The ocean connects everything: what floats today will one day sink, fragment and reappear in new forms. Our task is to make sure that what we leave behind is less damaging than what we have already set adrift.

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Kate Spencer receives funding from NERC, Lloyd’s Register Foundation and EU Interreg IV programme Preventing Plastic Pollution

Nan Wu works for Queen Mary University of London and the British Antarctic Survey. Nan Wu receives funding from Lloyds Register Foundation, UK, Queen Mary University of London Principal Studentships, EU INTERREG France (Channel) England project ‘Preventing Plastic Pollution’ co-financed by the European Regional Development Fund’.

– ref. Scientists have puzzled over what happens to plastic as it breaks down in the ocean – our new study helps explain the mystery – https://theconversation.com/scientists-have-puzzled-over-what-happens-to-plastic-as-it-breaks-down-in-the-ocean-our-new-study-helps-explain-the-mystery-268305

Source: The Conversation – UK – By David Cornell, Senior Lecturer in Philosophy, University of Lancashire

As far back as 1980, the American philosopher John Searle distinguished between strong and weak AI. Weak AIs are merely useful machines or programs that help us solve problems, whereas strong AIs would have genuine intelligence. A strong AI would be conscious.

Searle was sceptical of the very possibility of strong AI, but not everyone shares his pessimism. Most optimistic are those who endorse functionalism, a popular theory of mind that takes conscious mental states to be determined solely by their function. For a functionalist, the task of producing a strong AI is merely a technical challenge. If we can create a system that functions like us, we can be confident it is conscious like us.

Recently, we have reached the tipping point. Generative AIs such as Chat-GPT are now so advanced that their responses are often indistinguishable from those of a real human – see this exchange between Chat-GPT and Richard Dawkins, for instance.

This issue of whether a machine can fool us into thinking it is human is the subject of a well-known test devised by English computer scientist Alan Turing in 1950. Turing claimed that if a machine could pass the test, we ought to conclude it was genuinely intelligent.

Back in 1950 this was pure speculation, but according to a pre-print study from earlier this year – that’s a study that hasn’t been peer-reviewed yet – the Turing test has now been passed. Chat-GPT convinced 73% of participants that it was human.

What’s interesting is that nobody is buying it. Experts are not only denying that Chat-GPT is conscious but seemingly not even taking the idea seriously. I have to admit, I’m with them. It just doesn’t seem plausible.

The key question is: what would a machine actually have to do in order to convince us?

Experts have tended to focus on the technical side of this question. That is, to discern what technical features a machine or program would need in order to satisfy our best theories of consciousness. A 2023 article, for instance, as reported here in The Conversation, compiled a list of 14 technical criteria or “consciousness indicators”, such as learning from feedback (Chat-GPT didn’t make the grade).

But creating a strong AI is as much a psychological challenge as a technical one. It is one thing to produce a machine that satisfies the various technical criteria that we set out in our theories, but it is quite another to suppose that, when we are finally confronted with such a thing, we will believe it is conscious.

The success of Chat-GPT has already demonstrated this problem. For many, the Turing test was the benchmark of machine intelligence. But if it has been passed, as the pre-print study suggests, the goalposts have shifted. They might well keep shifting as technology improves.

Myna difficulties

This is where we get into the murky realm of an age-old philosophical quandary: the problem of other minds. Ultimately, one can never know for sure whether anything other than oneself is conscious. In the case of human beings, the problem is little more than idle scepticism. None of us can seriously entertain the possibility that other humans are unthinking automata, but in the case of machines it seems to go the other way. It’s hard to accept that they could be anything but.

A particular problem with AIs like Chat-GPT is that they seem like mere mimicry machines. They’re like the myna bird who learns to vocalise words with no idea of what it is doing or what the words mean.

This doesn’t mean we will never make a conscious machine, of course, but it does suggest that we might find it difficult to accept it if we did. And that might be the ultimate irony: succeeding in our quest to create a conscious machine, yet refusing to believe we had done so. Who knows, it might have already happened.

So what would a machine need to do to convince us? One tentative suggestion is that it might need to exhibit the kind of autonomy we observe in many living organisms.

Current AIs like Chat-GPT are purely responsive. Keep your fingers off the keyboard and they’re as quiet as the grave. Animals are not like this, at least not the ones we commonly take to be conscious, like chimps, dolphins, cats and dogs. They have their own impulses and inclinations (or at least appear to), along with the desires to pursue them. They initiate their own actions on their own terms, for their own reasons.

Perhaps if we could create a machine that displayed this type of autonomy – the kind of autonomy that would take it beyond a mere mimicry machine – we really would accept it was conscious?

It’s hard to know for sure. Maybe we should ask Chat-GPT.

David Cornell does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. The hardest part of creating conscious AI might be convincing ourselves it’s real – https://theconversation.com/the-hardest-part-of-creating-conscious-ai-might-be-convincing-ourselves-its-real-268123

Source: The Conversation – UK – By Stefano Arlaud, PhD candidate in Time Processing and Metacognition of Time Processing, SBBS, Queen Mary University of London

Most animals, including humans, carry an internal lunar clock, tuned to the 29.5-day rhythm of the Moon. It guides sleep, reproduction and migration of many species. But in the age of artificial light, that ancient signal is fading – washed out by the glow of cities, screens and satellites.

Just as the circadian rhythm keeps time with the 24-hour rotation of the Earth, many organisms also track the slower rhythm of the Moon. Both systems rely on light cues, and a recent study analysing women’s menstrual cycles shows that as the planet brightens from artificial light, the natural contrasts that once structured biological time are being blurred.

Read more:
Five animals that behave differently in moonlight

Plenty of research suggests the lunar cycle still influences human sleep. A 2021 study found that in Toba (also known as Qom) Indigenous communities in Argentina, people went to bed 30-80 minutes later and slept 20-90 minutes less in the three-to-five nights before the full Moon.

Similar, though weaker, patterns appeared among more than 400 Seattle students in the same study, even amid the city’s heavy light pollution. This suggests that electric light may dampen but not erase this lunar effect.

The researchers found that sleep patterns varied not only with the full-Moon phase but also with the new- and half-Moon phases. This 15-day rhythm may reflect the influence of the Moon’s changing gravitational pull, which peaks twice per lunar month, during both the full and new Moons, when the Sun, Earth and Moon align. Such gravitational cycles could subtly affect biological rhythms alongside light-related cues.

Laboratory studies have supported these findings. In a 2013 experiment, during the full Moon phase participants took about five minutes longer to fall asleep, slept 20 minutes less, and secreted less melatonin (a hormone that helps regulate the sleep-wake cycle). They also showed a 30% reduction in EEG slow-wave brain activity – an indicator of deep sleep.

Their sleep was monitored over several weeks covering a lunar cycle. The participants also reported poorer sleep quality around the full Moon, despite being unaware that their data was being analysed against lunar phases.

Perhaps the most striking evidence of a lunar rhythm in humans comes from the recent study analysing long-term menstrual records of 176 women across Europe and the US.

Before around 2010 – when LED lighting and smartphone use became widespread – many women’s menstrual cycles tended to begin around the full Moon or new Moon phases. Afterwards, that synchrony largely vanished, persisting only in January, when the Moon-Sun-Earth gravitational effects are strongest.

The researchers propose that humans may still have an internal Moon clock, but that its coupling to lunar phases has been weakened by artificial lighting.

A metronome for other species

The Moon acts as a metronome for other species. For example, coral reefs coordinate mass spawning events with precision, releasing eggs and sperm under specific phases of Moonlight.

In a 2016 laboratory study, researchers working with reef-building corals (for example A. millepora) replaced the natural night light cycle with regimes of constant light or constant darkness. They found that the normal cycling of clock-genes (such as the cryptochromes) was flattened or lost, and the release of sperm and eggs fell out of sync. These findings suggest lunar light cues are integral to the genetic and physiological rhythms that underlie synchronised reproduction.

Other species, such as the marine midge Clunio marinus, use an internal “coincidence detector” that integrates circadian and lunar signals to time their reproduction precisely with low tides. Genetic studies have shown this lunar timing is linked to several clock-related genes – suggesting that the influence of lunar cycles extends down to the molecular level.

However, a 2019 study found that the synchrony of wild coral spawning is breaking down. Scientists think this may be due to pollutants and rising sea temperatures as well as light pollution. But we know that light pollution is causing disruption for many wildlife species that use the Moon to navigate or time their movements.

Near-permanent brightness

For most of human history, moonlight was the brightest light of night. Today, it competes with an artificial glow visible from space. According to the World Atlas of Artificial Night Sky Brightness, more than 80% of the global population – and nearly everyone in Europe and the US – live under a light-polluted sky (one that is bright enough to hide the Milky Way).

Read more:
For medieval people, the Moon was both a riddle and a blessing

In some countries such as Singapore or Kuwait, there is literally nowhere without significant light pollution. Constant sky-glow from dense urban lighting keeps the sky so bright that night never becomes truly dark.

This near-permanent brightness is a by-product of these countries’ high population density, extensive outdoor illumination, and the reflection of light off buildings and the atmosphere. Even in remote national parks far from cities, the glow of distant lights can still be detected hundreds of kilometres away.

In cognitive neuroscience, time perception is often described by pacemaker–accumulator models, in which an internal “pacemaker” emits regular pulses that the brain counts to estimate duration. The stability of this system depends on rhythmic environmental cues – daylight, temperature, social routines – that help tune the rate of those pulses.

Losing the slow, monthly cue of moonlight may mean that our internal clocks now run in a flatter temporal landscape, with fewer natural fluctuations to anchor them. Previous psychological research has found disconnection from nature can warp our sense of time.

The lunar clock still ticks within us – faint but measurable. It shapes tides, sleep and the rhythms of countless species. Yet as the night sky brightens, we risk losing not only the stars, but the quiet cadence that once linked life on Earth to the turning of the Moon.

Stefano Arlaud does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. Humans have an internal lunar clock – but light pollution is disrupting it – https://theconversation.com/humans-have-an-internal-lunar-clock-but-light-pollution-is-disrupting-it-266717

Source: The Conversation – UK – By Gerda Wielander, Professor of Chinese Studies, University of Westminster

Chinese authorities detained Ezra Jin, the leader of the Zion Church, on October 10 alongside more than 30 church staff and pastors. The arrests come amid the largest crackdown on Christian churches in China in recent years, and have put renewed light on Beijing’s attempts to curb religious activities in China.

The Zion Church, a large unregistered church with congregations across China, has been on the authorities’ radar for many years. So the question is not why the crackdown is happening, but why it is happening now. China’s tense relations with the US have as much to do with this as domestic religious policy.

China’s relationship with Christianity is complex, and has been marked by periods of tolerance and persecution. The country officially recognises five religions: Buddhism, Daoism, Islam, Catholicism and Protestantism. Of these, only Buddhism and Daoism are regarded as indigenous religions and central to Han Chinese culture.

Together with Confucianism, they formed the so-called three teachings that provided the spiritual and ethical foundation of Chinese society throughout much of its imperial history (from 200BC to 1911).

Other religions flourished alongside these, including Islam and Christianity, both of which found their way into China centuries ago via trade routes. The earliest historical sources date the arrival of Nestorian Christians in China in the 7th century.

But the first major growth spurt of Chinese Christianity only occurred in the 19th century. This period saw China sign various treaties with western powers, which opened the doors for Protestant missionaries and led to the establishment of Protestant charitable institutions.

At the same time, the presence of western missionaries in China fuelled xenophobic movements. These movements ultimately contributed to the downfall of the empire. Christanity’s association with western imperialism continues to cloud Beijing’s view of the faith to this day.

After the founding of the People’s Republic of China in 1949, all foreign Christians were expelled from the country and state-run self-governing bodies were created for all main religions.

Dissatisfaction with these bodies – which was related to, among other things, the requirement to cut ties with churches and religious authorities outside China – led to the formation of unregistered churches. These churches, which are also known as house churches, have existed outside of state control ever since.

Arrests and severe persecutions of Christians started in the 1950s and continued, as for all other religious practices, during the Cultural Revolution. This was a ten-year period between 1966 and 1976 of extreme political upheaval and violence.

But, as the country emerged from the Cultural Revolution, it became clear that religious belief had survived in a sustained fashion despite severe repression. And the more liberal 1980s enabled the second growth spurt of Chinese Christianity.

The new political climate allowed more space to practice religion. This more open climate also meant that ties with churches abroad could be informally reinstated and that foreign missionaries, often in the form of English teachers on campus, returned to China.

The rapid growth of Christianity during this period led some observers to argue that Chinese Christians could be a decisive factor in the global balance of power.

Cracking down on religion

It’s hard to estimate how many Christians there are in China today. Official estimates are generally considered too low, while predictions by international Christian organisations are probably too high.

The generally accepted figure settled at around 90 million earlier this millennium, which puts the number of Christians in China in line with the number of Communist party members. This number is unlikely to have grown significantly since then. Research from January 2025 suggests that the number of Chinese Christians has been plateauing for the past 20 years.

The reasons for this are complex. The main concern of pastors and church leaders in the 2000s was how to retain new converts, especially among the younger generation. But China’s religious policy under Xi Jinping will also have been a factor.

From the start of his leadership in 2013, Xi has struck a fundamentalist tone. He has promoted elements of traditional Chinese culture paired with socialist values as orthodox state doctrine. At the same time, he has severely repressed religions considered a potential threat to the state. This has played out most starkly in the persecution of Uyghur Muslims in Xinjiang, but it has also affected Chinese Christians.

New regulations on religion were passed in 2015, which involved tighter state control of religious sites, church finances and involvement in charitable activities. One year later, Xi formally introduced the need for “sinicisation” of religion – the closer assimilation of all religions to Chinese state ideology.

This policy came with five-year plans that heralded the destruction of religious statues and the visual alteration of religious buildings. It also introduced more emphasis on the commonality between socialism and Christianity in doctrine.

The forcible removal of crosses from church buildings and the 2018 detention and subsequent sentencing to nine years in prison of Wang Yi, a prominent church leader, were further signs of the severity of the crackdown.

One particular bone of contention that further blights the lives of ordinary Christians in China is the close link between some unregistered churches, or individual people within them, and evangelist lobbying groups in the US.

Chinese-American Christians close to the Republican party are often instrumental in providing support for prominent exiled figures. They also ensure that the prosecution of Chinese Christians remains high on the agenda in bilateral relations. In turn, repressive measures tend to intensify when relations between China and the US deteriorate.

It is in this context that the timing of the recent crackdown needs to be understood. Sweeping in on a well-known unregistered church like the Zion Church, whose founder’s daughter is a US Senate staffer, is as much about Xi sending a signal to Washington as it is about controlling religious activity at home.

Unless US-China relations improve, Chinese Christians have to expect that more such signals may follow.

Gerda Wielander received funding from the UK’s Arts and Humanities Research Council (AHRC) to conduct research for her book Christian Values in Communist China (Routledge 2013).

– ref. Why Beijing is looking to exert tighter control over Chinese Christians   – https://theconversation.com/why-beijing-is-looking-to-exert-tighter-control-over-chinese-christians-267571

Source: The Conversation – UK – By Dan Baumgardt, Senior Lecturer, School of Psychology and Neuroscience, University of Bristol

Trick or treat? Something I won’t be hearing at my own door this Halloween. Myself and the other misers of our village will once again be shunning anyone ringing the bell in search of sugar. Apparently, placing a pumpkin outside your house is the standard invitation to call — as much effort as buying the wretched sweets in the first place. Bah humbug (and, since you ask, there won’t be any of those in the house, either).

And just as well, really. Not just because of my general curmudgeonliness, but have you seen what all that sugar does to you? A lot more than cavities in your teeth and hyperactive kids climbing the curtains — try gut inflammation, kidney damage and heart disease. Literally.

Take the case of one unfortunate chap in the news recently who consumed a whole 3kg bag of jelly cola bottles over three days. He ended up in hospital, blocked up with gelatine and overloaded with sugar that caused acute diverticulitis: inflammation of small pouches in the colon, which generates severe abdominal pain, fever and sometimes even rectal bleeding.

Luckily he recovered, though with a new and healthy aversion to cola bottles, which is probably for the best. It just goes to show that too much of a good thing can be dreadful.

Let’s take a peek at some of the other perils associated with confectionery. As you’ll see, sugar isn’t the only enemy.

It might help the medicine go down, but Mary Poppins never had to take Jane and Michael to the dentist, did she? Most of us are taught from an early age that sugar is the enemy – and, in truth, it can be.

Sugar starts its damage the moment it hits your mouth. It feeds the many colonies of bacteria living there, which proliferate and release acids that corrode tooth enamel. Prolonged exposure then wears through to the deeper layers of the tooth, causing cavities and hidden decay. Bacterial plaque development also generates gum irritation – otherwise known as gingivitis, which can also lead to persistent bad breath as bacteria release unpleasant sulphur compounds.

Once absorbed from the gut, sugar spikes blood glucose levels. These cause short-term bursts of hyperactivity and anxiety, followed by fatigue and irritability as levels crash – setting up a vicious circle of cravings and overconsumption.

Many blame sugar for diabetes mellitus – the medical term for disorders that affect how the body processes blood glucose – and in the case of Type 2 diabetes, they’re not wrong. High-sugar diets can drive weight gain and insulin resistance, the hallmarks of the disease. It doesn’t, however, cause Type 1 diabetes, where the pancreas stops producing insulin. But the effects of too much sugar reach far beyond diabetes, contributing to heart and liver disease, high cholesterol and high blood pressure, to name but a few.

Liquorice all-sorts of issues

Nigella Lawson is well known for showcasing her black toolbox compendium of liquorice-related goodies – some decidedly more palatable than others. What many may be surprised to learn is that the traditional black stuff can pack quite a punch.

It’s made from the root of the plant Glycyrrhiza glabra – and the aromatic extract mixed with sugar, gelatine or starch to create the chewy confection we all recognise. Its active ingredient, glycyrrhizin, doesn’t just bring that distinctive anise taste; it can also meddle with your hormones.

In small doses, liquorice can help relieve indigestion and may have some anti-inflammatory properties. I’m quite partial to it myself, so imagine my shock in a renal lecture at medical school years ago to learn it can cause high blood pressure and low potassium levels. Glycyrrhizin mimics the effects of adrenal hormones such as cortisol and aldosterone, which regulate blood pressure, and fluid and electrolyte balance. In excess, this mimicry can trigger fluid retention, muscle breakdown, and even heart, liver or kidney failure.

Advisory bodies have actually set recommended limits for consumption: less than 100mg of glycyrrhizin a day for adults – roughly 50g of traditional black liquorice. It’s also best avoided altogether if you suffer from significant heart or kidney disease. So if you’re knocking back the allsorts, do so sparingly.

Sherbets and super sours

One of my own childhood favourites was the sherbet Dip Dab – a bag of mouth-puckering powder with a strawberry lolly for dipping. It seemed like magic: sweet, sour and fizzy all at the same time. What I’ve since discovered is that it’s very easy to make – just sugar and citric acid from the chemist’s shop.

Citric acid also gives those “super sour” bonbons their face-contorting power. Several studies have found such sweets possess a pH as low as 2.3 – intensely acidic – and can drastically alter the acidity of saliva, stripping enamel from teeth. The erosive potential of some commercially available sweets, especially on milk teeth, is staggering.

Beyond the mouth, the effects are less clear. There are media reports of mouth ulcers from sour sweets, and we also know that acidic irritation of the stomach lining is known to trigger inflammation and ulceration. The impact of sherbets and sours on the gut remains to be seen — but I wouldn’t volunteer to find out.

So, while candies and chocolates can be enjoyed responsibly, it’s worth remembering their wider effects — especially in children, whose sweet tooth is more pronounced. Consider ways to limit sugar intake, so the occasional treat doesn’t quickly become a double-trouble trick. And from there a longer-term issue.

After all, it’s Halloween — and the last thing you want is your own digestive system playing nasty tricks on you.

Dan Baumgardt does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. Is Halloween more trick than treat? The dangers of overeating sugar, liquorice and sherbet – https://theconversation.com/is-halloween-more-trick-than-treat-the-dangers-of-overeating-sugar-liquorice-and-sherbet-267554

Source: The Conversation – UK – By Michael Rowe, Reader in European History, King’s College London

The Napoleonic wars were fought on a bigger scale than any conflict that had gone before. Though concentrated in Europe, their impact was global. They conjure up images of huge battles fought between armies in colourful and flamboyant uniforms. Given all this, it is unsurprising that Napoleonic-era military history still looms large in our cultural imagination.

It is the wider social and cultural effects of those wars, however, that dominates current historical research. This includes the impact of those wars on attitudes towards race.

The National Army Museum in London has recently identified the likely subject of a portrait of a black soldier in its collection as Private Thomas James. Speaking to the Guardian to mark both the identification and restoration of the portrait, curator Anna Lavelle highlighted the British army as a place of racial equality. Meanwhile, the museum’s director, Justin Maciejewski, suggests that the painting underscores the shared sense of purpose historically held by British soldiers when facing common enemies such as Napoleon.

The vast majority of ordinary privates who fought and died in the Napoleonic wars have left no record, irrespective of their ethnicity. This in itself makes the recent identification – though not with a 100% degree of certainty – of the subject of this portrait important. It might be taken as evidence for an argument already made by Napoleonic specialists: that the demands of war provided an opportunity for previously marginalised groups to improve their status.

This applied not only to enslaved men of African heritage, but to other groups including, for example, Jewish people in Central Europe who fought against Napoleon in the armies of Austria and Prussia. Like Irish Catholics in the British armed forces, they and their supporters used their patriotic engagement to justify greater equality in the emancipation debates that followed the end of the Napoleonic wars.

James’s experience was therefore far from unusual. Within the British armed forces of the time, the majority of black men served in the so-called West India Regiments, formed in the 1790s to fight the French in the Caribbean. These men were, in practice, “purchased” by a British government desperate for additional manpower. They served in an environment infamous for its horrendous attrition rates caused by tropical diseases. Whether this process can be heralded as a model of modern diversity and inclusion practices seems doubtful, to say the least.

That said, these black soldiers were by virtue of their military service freed from slavery. While wearing the king’s coat, they were subject to military disciplinary codes that were ostensibly colour-blind, unlike the colonial codes that had previously regulated their lives.

From their perspective, the British military effort in the Americas undoubtedly led to an improvement in status. At the same time, vast investments in naval infrastructure in the Caribbean created new economic opportunities for freed black people – both women and men. These opportunities were especially significant in the islands of that strategically vital region.

There is a further dimension to the portrait of James. The white colour of his uniform deviates from that of most of the regiment, which would have been dark blue. Taken together with the prominently displayed cymbals, this suggests James was part of the military band common to regiments in all the armies that fought the Napoleonic Wars.

Music was a feature not only of ceremonial occasions but an important ingredient to good morale. It even played a role in communications. Black musicians were often prominent in military bands in this period, and not only in the British army.

They were also common in the armies of German states even before the Napoleonic wars – somewhat surprisingly, given that these states, unlike Britain, did not possess any African or Caribbean colonies. The background to this fashion derives from the Ottoman origins of modern military music, and its adoption by European armies during the 18th century. Initially, western armies employed Turkish musicians in these bands, but over time they were replaced by men of African origin.

African musicians were much prized and respected. They added lustre to the regiment and prestige to the colonel. More widely, they fed into a wider societal demand for the “exotic”.

Within Napoleonic-era armies, this was manifested in the undue prominence given to military units that fed Orientalism – including, most famously, the Mamelukes of the Imperial Guard, who served close to the emperor himself, and who appear in almost every Napoleonic-era battle painting. Other examples include the Russian Cossacks, whose attire was so exotic that it inspired innovations in civilian fashion when the Tsarist army occupied Paris after Napoleon’s defeat.

Armies reflect the societies from which they are drawn. And while Napoleonic-era armies provided unusual, if not unique, opportunities for those otherwise on the margins, they also reinforced notions of difference that were fairly common at the time.

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Michael Rowe does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. What a newly identified portrait of a black Napoleonic soldier reveals about British Army diversity – https://theconversation.com/what-a-newly-identified-portrait-of-a-black-napoleonic-soldier-reveals-about-british-army-diversity-268230