The study, recently published online in Scientific Reports, found that in a mouse model of human type 2 diabetes, Rhodiola rosea lowered fasting blood sugar levels, improved response to insulin injections, modulated the composition of bacteria in the gastrointestinal tract and decreased several biomarkers of inflammation.

“The prevalence of type 2 diabetes and the associated health costs have risen steadily in recent decades. Humans have used plants and natural products for thousands of years to treat diseases, and our study shows Rhodiola rosea is a good candidate for further investigation,” said corresponding author Dr. Mahtab Jafari, UCI professor of pharmaceutical sciences. “Current treatment recommendations include lifestyle changes as well as oral and intravenous medications. However, these drugs have significant limitations or side effects, increasing the need for new therapeutic interventions.”

The team utilized a genetically engineered mouse model that develops obesity, insulin resistance and high blood sugar, similar to advanced human type 2 diabetes, to test whether Rhodiola rosea could improve glucose homeostasis. In the study, cohorts of age-matched male and female mice were randomly assigned to one of two groups: control, which received water, or experimental, which were administered Rhodiola rosea extract.

“Our findings suggest that Rhodiola rosea might be beneficial for treating type 2 diabetes, acting through changes in the microbiome that result in increased gut barrier integrity and decreased translocation of inflammatory molecules into the blood circulation,” Jafari said. “Gut barrier integrity influences body weight and insulin response, and this botanical product may improve the responses of liver and muscle tissues to insulin produced by the pancreas.”

The team’s next steps are to perform a larger follow-up study in a different mouse model of obesity-induced diabetes to confirm these findings and to investigate the molecular mechanisms involved. Ultimately, Jafari hopes to conduct Rhodiola rosea clinical trials in patients with type 2 diabetes.

“Our research presents a solid case for the importance of conducting high-quality pre-clinical studies based on sound methodologies to evaluate the efficacy of standardized plant extracts. We have set the stage for human clinical studies, with the ultimate goal of improving health outcomes for type 2 diabetes patients,” Jafari said.

The team included students and faculty members from UCI, UCI Health and Brigham Young University in Provo, Utah.

This work was supported by the UCI School of Medicine-Pharmaceutical Sciences Collaborative Research Funds and Mr. and Mrs. John P. and Lois C. Wareham.

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Species declines are strongly associated with Human Development Index

An international research team led by iDiv, MPI-EVA, and the University of Bonn, in collaboration with the UFZ, Leipzig University, the Friedrich Schiller University Jena and many other institutions has now investigated the biodiversity conservation effectiveness of 114 national parks in 25 countries in Africa and Europe on the basis of changes in abundances of 464 mammal and bird species. Within the surveyed ten-year period from 2007 to 2017, they found that the effectiveness of the 66 African and 48 European parks strongly depended on the respective local and national economic and societal conditions — which are reflected in the Human Development Index (HDI). A likely explanation is that resource demand from national parks is higher and less regulated when the HDI is low, making the parks less effective. The parks located in countries with highest HDI values showed average declines in species abundance of about 10% compared to more than 25% in parks located in countries with lowest HDI.

National parks do not guarantee 100% protection

“But we also found that seemingly effective national parks embedded in favourable socioeconomic context (such as high HDI) are not necessarily a generic solution for ideal national park management,” says lead author Dr Tsegaye Gatiso, researcher at the University of Bonn and iDiv. “Finally, no socioeconomic conditions and no set of currently implemented conservation measures can guarantee the elimination of threats to biodiversity. Species may still decline in the same national park under less favourable conditions because protected areas are an inseparable part of a dynamic, complex social-ecological system.”

Better design of national parks network needed

The researchers, therefore, conclude that a marginal gap to fully effective national parks remains. A critical need is an improved design of the national park network and associated management to reduce threats and make it ecologically functional. Concerted actions that include expanding the national park network, establishing corridors between protected areas to facilitate the dispersal of species between them, and, very importantly, improving conditions for biodiversity outside national parks are the most critical elements to halt biodiversity loss.

“Many national parks have become ‘islands in a desert of industrial agriculture, forestry and infrastructure’. The poor ecological conditions outside national parks reduce the species’ abundance. After all, they do not orient their distribution areas to national park boundaries set by humans. If they are then exposed to a variety of negative living conditions outside the parks, this also affects their abundance inside the parks,” adds the study’s senior author, Dr Hjalmar Kühl, a scientist at iDiv and MPI-EVA. “It is therefore important that the ecological conditions outside the parks are significantly improved. Protected areas, and especially national parks, are sensors for the state of our planet’s biodiversity. The lack of effectiveness of observed parks must be taken very seriously, and we must make great efforts to significantly improve the network of protected areas in terms of its ecological functionality.”

The study was funded by the German Center for Integrative Biodiversity Research (iDiv) (DFG FZT 118, 202548816; T.T.G. and H.S.K.) and the Robert Bosch Foundation (grant number 32.5.8043.0016.0; H.S.K.).

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Materials provided by German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig. Original written by Urs Moesenfechtel. Note: Content may be edited for style and length.

Solar panels are typically a deep black color because their job is to absorb light, whereas a red car looks red because the finish reflects red light instead of absorbing it. Most attempts to give these devices color, then, will decrease their ability to absorb light and generate power. One alternative is to use structural sources of color that take advantage of microscopic shapes to only reflect a very narrow, selective portion of light, like the scales on butterfly wings. However, previous technologies attempting to incorporate structural color gave panels an undesirable iridescence or were expensive to implement at a large scale. So, Tao Ma, Ruzhu Wang, and colleagues wanted to develop a way of giving solar panels color using a structural material that would be easy and inexpensive to apply, and that would maintain their ability to produce energy efficiently.

The team sprayed a thin layer of a material called a photonic glass onto the surfaces of solar cells. The glass was made of a thin, disorderly layer of dielectric microscopic zinc sulfide spheres. Although most light could pass through the photonic glass, selective colors were reflected back based on the sizes of the spheres. Using this approach, the researchers created solar panels that took on blue, green and purple hues while only dropping the efficiency of power generation from 22.6% to 21.5%. They also found that solar panels manufactured with this photonic glass layer maintained their color and performance during standard durability tests, and that the fabrication could be scaled up. The researchers plan to explore ways to make the colors more saturated, as well as methods to achieve a wider range of colors.

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The finding comes from the study of hillsides in a far north region of Russia, where the researchers also found a significant and rapid increase of collapsed hillsides. The collapses feature landslides that gradually expose more of the permafrost for thawing — and more carbon for release.

Global climate models don’t account for the once-frozen carbon set free by these collapsing hillsides. The researchers say that needs to change.

The findings were published July 15 in The Cryosphere, a journal of the European Geosciences Union. They are the first based on the use of satellite imagery to estimate carbon release from slumping Arctic hillsides.

“Permafrost landscapes are expected to change profoundly over the next decades,” said Simon Zwieback, a University of Alaska Fairbanks Geophysical Institute assistant professor and one of the research paper’s authors. “Among the many consequences of this is the release of greenhouse gasses such as carbon dioxide, which can exacerbate climate change.”

Similar thaw slumps are also widespread in Russia’s Yamal Peninsula in Siberia, in northwestern Canada and in Canada’s Arctic archipelago.

Doctoral student Philipp Bernhard of the Swiss Federal Institute of Technology in Zürich and Irena Hajnsek of the Zürich institute and the German Aerospace Center also worked on the research. Zwieback and Hajnsek were Bernhard’s Ph.D. advisors.

The work focused on 10,500 square miles in the northern Taymyr Peninsula of Russia’s Siberia, an area bounded by the Byrranga Mountains to the south and the Kara Sea to the north.

The researchers compared satellite images from two time periods — 2010-2017 and 2018-2021 — to note elevation changes and movement of debris and of the slump’s exposed leading edge. They then incorporated a soil organic carbon map and made assumptions about the ground’s ice content and its carbon stores to calculate the amount of organic carbon released.

An ice sheet covered the entire study region around 130,000 years ago, with subsequent periods of ice retreat and advance covering a smaller and smaller area.The most recent retreat occurred at the end of the last ice age and was largely completed 12,000 years ago.

Satellite images revealed the spread of thaw slumps in areas containing remnants of that long-ago ice sheet.

A retreating sheet usually leaves behind substantial quantities of ice covered by clay, sand, gravel and rocks, particularly along the ice sheet’s edges. The retreating sheet that once covered the present-day Taymyr region created several of these ice-rich zones, referred to as ice-marginal zones. Two of those zones are in the researchers’ study area.

Images of the study area showed an increase in slumps from 82 in the 2010-2017 study period to 1,404 in the 2018-2021 period, with nearly all of that increase occurring during the region’s extremely warm 2020.

The images also showed that the annual volume of affected material increased by about 43 times from the first to second periods.

“The extreme warmth was compounded by there being a lot of ground ice close to the surface,” Zwieback said. “This is due to the long-term legacy of past ice ages but also to the fact that so much of this old ice is still there because summers are usually cool and there are no fires.

“And the ice is not well protected by insulating organic layers because there’s not much life in the harsh climate,” he said.

Alaska has thaw slumps but not nearly as many as those in Canada and Russia. Alaska also has other hillslide deformations caused by thawing permafrost, and these may contribute to climate change, Zwieback said.

Little research on such a large geographic scale as that in the Taymyr Peninsula exists about thaw slumps. The work of Zwieback, Bernhard and Hajnsek shows that the carbon release from thawing Arctic hillsides must be accounted for in assessing the Arctic’s carbon cycle. Researchers also need to quantify how much of it is turned into greenhouse gasses such as carbon dioxide.

“The big challenge is to quantify and predict where, when and how much carbon dioxide is released,” Zwieback said.