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A diamond shatters easily, despite it being the hardest natural material. Atomically disordered forms of diamond made from buckyballs might not only overcome this problem, but also allow other properties to be optimized. Syntheses of amorphous and paracrystalline forms of diamond., Author(s): Alfonso San-Miguel Author Affiliations: How to make macroscale non-crystalline diamonds The brilliant facets of diamonds have entranced people throughout history and are a result of the ordered atomic structure [...]

Pressure and temperature phase transitions of nanomaterials often differ significantly from those of their bulk parents, offering novel approaches for the engineering of original materials. The importance or even the dominance of surface atoms in the nanoworld enhances the effects of environment, geometry, and intercalation. In the present article, we explore the current knowledge of these effects, as evidenced in the high pressure phase diagrams of nanomaterials such as nanocrystals, carbon nanotubes, fullerites, graphene, and other 2D systems, as well as nanoporous structures like clathrates or zeolites. Recent advances and future challenges in the use of extreme thermodynamic conditions to develop new functional nanomaterials, composites, or devices will be reviewed, along with the specificities of the experimental environment required for these investigations. [ABSTRACT FROM AUTHOR]

In Mediterranean areas, severe drought events are expected to intensify in forthcoming years as a consequence of climate change. These events may increase physiological and reproductive stress of wild populations producing demographic changes and distribution shifts. We used retrospective life tables to understand demographic changes on a wild population after severe drought events. We studied the impact of two extreme events (2003 and 2005) on the population dynamics of our model species, the red deer (Cervus elaphus). During both years, population density was high (40 and 36 ind/100 ha, respectively). Thus, we reconstructed retrospectively the age structure of the female part of the population for the period 2000–2010 by using data of known‐age individuals culled during the period 2000–2019 (n = 4176). Also, based on previous study results, we aimed to validate this methodology. Both extremely dry years, 2003 and 2005, produced marked and lasting cohort effects on population demography. Age pyramid the following years (2004 and 2006) revealed that the extreme drought caused the female fawn cohort to be similar or even smaller than the yearling cohort. Furthermore, these cohort effects were still perceptible 3 years after these severe events. Results agree with previous findings that showed a negative effect of severe drought events on female pregnancy rates and conception dates. Although simple, this study provides an empirical quantification of the demographic effects of severe drought events for a wild population which might be useful to understand future demographic changes under the context of climate change. [ABSTRACT FROM AUTHOR]

Human–elephant coexistence remains a major conservation and livelihood challenge across elephant Loxodonta africana range in Africa. This study investigates the extent of elephant crop damage on 66 farms in the Selous–Niassa corridor (Tanzania), to search for potential management solutions to this problem. We found that the relative abundance of highly preferred crops (area covered by preferred crops divided by the total area of each farm) was by far the most important factor determining crop damage by elephants. Eighteen crop types were ranked according to their preference by elephants. Sweet potatoes, bananas, peanuts, onions, pumpkins and maize were the most preferred crops, with maize the most common crop among those highly preferred. On average elephants damaged 25.7% of the cultivated farmland they entered. A beta regression model suggests that a reduction in the cultivation of preferred crops from 75 to 25% of the farmland area decreases elephant crop damage by 64%. Water availability (distance to the nearest waterhole) and the presence of private investors (mostly hunting tourism companies) were of lower importance in determining elephant crop damage. Thus, damage by elephants increased with shorter distances to waterholes and decreased in areas with private investors. However, further studies are required, particularly of the perceived costs and benefits of elephants to local communities. Farm aggregation and the use of non-preferred crops that also require less water would potentially reduce elephant damage but would be a major lifestyle change for some local communities. [ABSTRACT FROM AUTHOR]

Field-effect transistors based on individual carbon nanotubes with reduced Schottky barriers are studied up to pressures of 0.9 GPa and down to temperatures of less than 10 K. At ambient temperature and high pressure, complex effects are observed in a small bundle of tubes stemming from either the intrinsic modifications of the nanotubes at their ovalization, the evolution of barriers at the tube/electrodes contacts, or even both processes. Variations of the nanotube transport characteristics related to changes in the tube environment are most possibly also involved. Despite the highly complex pressure induced changes occurring in our device, low temperature measurements (<10 K) at high pressure (4.5 kbar) provide the first experimental evidence of Coulomb blockade at high pressure and the conservation of the ballistic behaviour of charges carriers in nanotubes under important stress-induced strain. [ABSTRACT FROM AUTHOR]