In the study, published in the journal Communications Biology, researchers examined over 800 places in the human genome known to be associated with adult height and also evaluated data suggesting that lower height increases the risk of developing type 2 diabetes and coronary heart disease.

The authors found no evidence of a causal link between height and type 2 diabetes risk once an individual’s body mass index was taken into account but reported a causal relationship between height and heart disease risk.

Many traditional risk factors for heart disease were investigated including, cholesterol, triglycerides, blood pressure, fat percentage, and socio-economic parameters including education and income, but results showed that they only account for a very small part of the effect of height on heart disease risk. The way our lungs function accounted for most of this effect.

Lead author, Dr Eirini Marouli from Queen Mary University of London said: “Understanding the causal relationship behind an observation such as the inverse relationship between adult height and heart disease risk is important in advancing our knowledge about the disease and has the potential to point towards lifestyle interventions that can impact disease prevention.

“Our results suggest that we need to assess lung function alongside someone’s height to have a better handle in predicting their risk in developing heart disease.”

Heart attacks are one of the most common causes of death worldwide. Nearly one in six men and one in ten women die from heart disease, therefore identifying heart disease risk factors, especially those that could be modified through early lifestyle interventions, is specifically important.

According to Professor Panos Deloukas from Queen Mary University of London, senior author of the study: “Individuals of shorter statute can consider regular exercise and the avoidance of a sedentary lifestyle and smoking to reduce their risk of heart disease given that, as we showed in this study, the effect of shorter height on the risk of heart disease is mediated by lung function.

“Our findings and further studies of this nature, empower efforts to promote a healthy lifestyle and in particular physical activity that can lead to improved lung function.”

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The research group recently engineered a silicon-graphene device that can transmit radiofrequency waves in less than a picosecond at a sub-terahertz bandwidth — that’s a lot of information, fast. Their work is described in a new paper published in the journal ACS Applied Electronic Materials.

“In this work, we explored the bandwidth limitation of the graphene-integrated silicon photonics for future optoelectronic applications,” said graduate student Dun Mao, the first author of the paper.

Silicon is a naturally occurring, plentiful material commonly used as a semiconductor in electronic devices. However, researchers have exhausted the potential of devices with semiconductors made of silicon only. These devices are limited by silicon’s carrier mobility, the speed at which a charge moves through the material, and indirect bandgap, which limits its ability to release and absorb light.

Now, Gu’s team is combining silicon with a material with more favorable properties, the 2D material graphene. 2D materials get their name because they are just a single layer of atoms. Compared to silicon, graphene has better carrier mobility and direct bandgap and allows for faster electron transmission and better electrical and optical properties. By combining silicon with graphene, scientists may be able to continue utilize technologies that are already used with silicon devices — they would just work faster with the silicon-graphene combination.

“Looking at the materials properties, can we do more than what we’re working with? That’s what we want to figure out,” said doctoral student Thomas Kananen.

To combine silicon with graphene, the team used a method they developed and described in a paper published in 2018 in npj 2D Materials and Application. The team placed the graphene in a special place known as the p-i-n junction, an interface between the materials. By placing the graphene at the p-i-n junction, the team optimized the structure in a way that improves the responsivity and speed of the device.

This method is robust and could be easily applied by other researchers. This process takes place on a 12-inch wafer of thin material and utilizes components that are smaller than a millimeter each. Some components were made at a commercial foundry. Other work took place in UD’s Nanofabrication Facility, of which Matt Doty, associate professor of materials science and engineering, is the director.

“The UD Nanofabrication Facility (UDNF) is a staff-supported facility that enables users to fabricate devices on length scales as small as 7 nm, which is approximately 10,000 times smaller than the diameter of a human hair,” said Doty. “The UDNF, which opened in 2016, has enabled new research directions in fields ranging from optoelectronics to biomedicine to plant science.”

The combination of silicon and graphene can be used as a photodetector, which senses light and produces current, with more bandwidth and a lower response time than current offerings. All this research could add up to cheaper, faster wireless devices in the future. “It can make the network stronger, better and cheaper,” said postdoctoral associate and the first author of the npj 2D Materials and Application article Tiantian Li. “That is a key point of photonics.”

Now the team is thinking about ways to expand the applications of this material. “We’re looking at more components based on a similar structure,” said Gu.

This work is funded by grants from AFOSR and NASA, and the team has a partial collaboration with Bell Labs.

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A team of researchers in the McKelvey School of Engineering and the School of Medicine at Washington University in St. Louis wanted to determine how length affected the mechanical efficiency of beating cilia. They found that most mechanical metrics, including force, torque and power, increased in proportion to the length of the cilia, but there was a “sweet spot” in terms of efficiency. The findings give insight into cilia in humans and how defects lead to disease, such as primary ciliary dyskinesia, which is associated with chronic respiratory infections, changes in the right-left axis and heart defects. The results will be published in the April 9 issue of Biophysical Journal.

The study was led by Mathieu Bottier, a postdoctoral researcher in the lab of Philip Bayly, the Lilyan & E. Lisle Hughes Professor of Mechanical Engineering and chair of the Department of Mechanical Engineering & Materials Science; and the lab of Susan K. Dutcher, professor of genetics and of cell biology and physiology at the School of Medicine. The researchers used high-speed video microscopy to analyze a model for cilia to determine their mechanical metrics. After analyzing nearly 400 videos, the team found that the most efficient beating of cilia was at its natural length of 10-12 microns, or about one-fifth the width of a human hair.

“Something we did not expect is that the short cilia would not be periodic,” Bottier said. “The cilia are all moving, but we find no actual pattern of beating — nothing was synchronized — and that was our first discovery.”

The team used Chlamydomonas reinhardtii, a single-cell green alga that normally swims with two propulsive tails and is frequently used as a model for mammalian cilia. Bottier and Kyle Thomas, a senior undergraduate student majoring in biomedical engineering, used a mutant with only one cilium that spins in place, allowing longer video recording. They removed the cilium, then recorded the regrowth by video. The cilium took about 90 minutes to return to its normal length, and while its waveform varied slightly from that of the standard cilia, its key characteristics were similar.

“We wanted to see the cilium beating, which we did with the video,” Bottier said. “Then we asked how we could describe it, and the best way was to look at the average beat. We recorded five or six cycles of beating that repeat periodically, and from those five or six, we can reconstruct one average, which will remove the eventual outliers.”

The cilium’s beating takes place via a series of bends that begin at its base and extend to the tip. The team found that periodic beating begins when cilia become longer than two to four microns, which means that a critical length is necessary for the cilia to beat. In previous research, scientists had not studied cilia shorter than five or six microns, Bottier said. Another new observation is that the beat frequency in periodically-beating cilia is quite consistent over the normal range of cilium length, although it decreases slightly as length increases from four microns to 12 microns, Bayly said.

This work may help to understand human mutations that make cilia short and how short cilia will impact the patient’s outcome, Dutcher said.

Thomas said the research provides a better understanding of how cilia operate and what causes the oscillations.

“There are a lot of different models presented on what drives this bending pattern, so this study helped to learn which models are more accurate and which may have inaccuracies, so we can understand when there is a cilia dysfunction, what causes it because that could spark some conversations on how we go about treating it,” Thomas said.

Researchers used state-of-the-art tools to help identify the most suitable location for lynx reintroduction in Scotland — and how this choice might affect the size of a population and its expansion over subsequent decades. Significantly, they believe their model will inform and enhance decision-making around large carnivore reintroductions worldwide.

The study was led by University of Stirling PhD researcher Tom Ovenden as part of his Masters in Environmental Forestry at Bangor University, with support from the University of Aberdeen.

Mr Ovenden said: “Reintroducing large carnivores is often complicated and expensive, meaning that getting things right first time is extremely important. Therefore, advances in modelling approaches, as utilised during our study, are extremely valuable.

“Our research considered several proposed reintroduction sites, showing how these models can be used as a safe and relatively inexpensive way of assessing the suitability of reintroduction proposals and providing the evidence required to inform decision-making at an early stage.

“Recent advances in both ecological theory and modelling approaches have made the incorporation of individual species’ complex behaviours in novel environments more realistic. We applied this approach to the potential reintroduction of Eurasian lynx in Scotland — and demonstrated the power of this new, sophisticated model. Our research demonstrates the potential of this approach to be applied elsewhere to help improve reintroduction success in large carnivores, from the safety of a modelling environment.”

The lynx is thought to have become extinct in the UK during the medieval period, around 1,300 years ago. In recent years, its potential reintroduction has been widely debated.

Using current land cover data, Mr Ovenden conducted an initial desk-based study to establish the current location and extent of suitable forest habitat for lynx in Scotland, updating historic work. Further research to identify the demographic and dispersal characteristics of the lynx elsewhere in Europe, provided the model with the necessary parameters.

The team used this information to investigate the suitability of three proposed release sites: the Scottish component of Kielder Forest, in the Borders; Aberdeenshire; and the Kintyre Peninsula. They used the model to assess how the lynx would establish a population, spread and colonise new habitat from each potential reintroduction site over a period of 100 years.

The results showed that Scotland possesses sufficient, connected habitat to offer a realistic chance of population establishment and that some sites are more suitable than others.

Of the three sites considered, the study indicated that the Kintyre Peninsula was the most suitable, with the population spreading across the Highlands in the 100 years following release. Significantly, the Central Belt would act as a barrier to colonisation between the Highlands and Southern Uplands providing evidence for two distinct habitat networks.

“This initial research is encouraging and suggests that Scotland is indeed ecologically suitable for the reintroduction of Eurasian lynx — but this suitability is highly dependent on where reintroduction takes place and more modelling work is required,” Mr Ovenden said. “Our research informs one aspect of a complex decision-making process that must involve a wide range of stakeholders and, as a result, it does not recommend whether we should, or should not, reintroduce Eurasian lynx to Scotland.

“We have established a solid foundation upon which more modelling can now be conducted, however, further research is required to assess other important issues — such as socio-economic factors and public attitudes — to enable informed, comprehensive decision-making. It is our hope that this tool will not only provide evidence to guide the current debate in Scotland, but can be used more widely in discussions around large carnivore reintroductions globally.”

Jo Pike, Director of Public Affairs at the Scottish Wildlife Trust, said: “Returning the lynx to our landscape as a top predator could help restore the health of Scotland’s natural ecosystems. Any future reintroduction would have to be carefully planned, widely consulted on, and rigorously assessed against national and international guidelines. This research is a useful contribution to the evidence base that needs to be developed over the coming years.”

Notably, Mr Ovenden wrote his entire dissertation using solar power, while running the Handa Island nature reserve, in the Inner Hebrides, for the Scottish Wildlife Trust. He worked under the supervision of Professor John Healey, of Bangor University, and collaborated with Dr Steve Palmer and Professor Justin Travis, of the University of Aberdeen.

Mr Ovenden is now working towards a PhD at Stirling, in collaboration with Forest Research and The Scottish Forestry Trust, on the resilience of UK forests to extreme climatic events.

The study, Improving reintroduction success in large carnivores through individual-based modelling: how to reintroduce Eurasian lynx (Lynx lynx) to Scotland, is published in Biological Conservation.