Search

High temperature and drought are widely known to cause a reduction of crop yield, but the simultaneously occurring risks in major producing countries and the associated uncertainty across various climate change scenarios remain unclear at the global scale. Here, we evaluate global maize yield loss risk (i.e., the probability of yield reduction by over 10% relative to historical trend yield during 1981–2010) across 30 hot and dry scenarios using regression, machine learning and process‐based models. Besides examining yield loss risk in a single country, we predict the potential risks simultaneously occurring in the top two and top ten producing countries. The three approaches agree on the aggravation of yield loss risk under dry and hot scenarios, but show large discrepancy in the magnitude and sensitivities. Specifically, 2°C warming alone could lead to a global yield loss risk of 73%, 100% and 62% based on regression, long‐short term memory (LSTM) and process‐based models, respectively, and warming‐induced risks can be further aggravated by droughts especially in process models. Global yield loss by over 10% would even become the new norm (i.e., yield loss probability is 100%) when temperature increases by over 2°C in some models. Importantly, the probabilities of yield loss simultaneously occurring in the top two countries (i.e., United States and China) and top ten countries are unexpectedly high and could even become 100% under extreme hot and dry scenarios. Our results highlight the large risks that future climate change may bring to multiple exporting and importing countries simultaneously, thus threating global food market and security. We also emphasize the important value of using different types of prediction approaches for yield projection under hot and dry scenarios, which enables more realistic estimation of uncertainty range than a single type of model. [ABSTRACT FROM AUTHOR]

Benthic invertebrate communities are deeply influenced by hydrological variability in surface freshwater habitats. However, the responses of macroinvertebrates composing stygofauna in aquifers and unsaturated groundwater environments are not well understood nor specifically studied. Here, we present two new cases of resistance to drying in groundwater‐dwelling animals: planarians of the genus Dendrocoelum and the isopod crustacean Monolistra pavani. Multiple surveys were performed in 53 caves of the Italian Alps and Apennines, sampling different stable and unstable subterranean aquatic environments. Planarians and crustaceans were searched visually and by distressing the substrate. When we detected individuals in dry sectors, we photographed them, observed their features, and released them in pools or streams of the same cave. We rinsed dry individuals of M. pavani in small tanks and recorded the time of reactivation. In a dried subterranean stream, we observed a Dendrocoelum planarian encapsulated in a thick mucus layer, which after a total of 5 min started gliding slowly and reached a length of 18 mm. During the drought of January–April 2022, we detected several individuals of M. pavani in dry areas of two caves. In total, 72% of the tested individuals were able to reactivate. This percentage decreased to 42% after 20 days of dryness. Time to reactivate ranged between 0 and 30 s. Living individuals were observed even after 39 days of drought. Our observations provide new insights into the natural history of groundwater‐dwelling invertebrate taxa that are often neglected in the studies of freshwater ecology. Resistance of groundwater‐dwelling animals to droughts has several implications for global climatic changes and could be species‐ and site‐specific, as previously observed in surface macroinvertebrates. [ABSTRACT FROM AUTHOR]

Wildfires devastated communities in Oregon and Washington in September 2020, burning almost as much forest west of the Cascade Mountain crest ("the westside") in 2 weeks (~340,000 ha) as in the previous five decades (~406,00 ha). Unlike dry forests of the interior western United States, temperate rain forests of the Pacific Northwest have experienced limited recent fire activity, and debates surrounding what drove the 2020 fires, and management strategies to adapt to similar future events, necessitate a scientific evaluation of the fires. We evaluate five questions regarding the 2020 Labor Day fires: (1) How do the 2020 fires compare with historical fires? (2) How did the roles of weather and antecedent climate differ geographically and from the recent past (1979–2019)? (3) How do fire size and severity compare to other recent fires (1985–2019), and how did forest management and prefire forest structure influence burn severity? (4) What impact will these fires have on westside landscapes? and (5) How can we adapt to similar fires in the future? Although 5 of the 2020 fires were much larger than any others in the recent past and burned ~10 times the area in high‐severity patches >10,000 ha, the 2020 fires were remarkably consistent with historical fires. Reports from the early 1900s, along with paleo‐ and dendro‐ecological records, indicate similar and potentially even larger wildfires over the past millennium, many of which shared similar seasonality (late August/early September), weather conditions, and even geographic locations. Consistent with the largest historical fires, strong east winds and anomalously dry conditions drove the rapid spread of high‐severity wildfire in 2020. We found minimal difference in burn severity among stand structural types related to previous management in the 2020 fires. Adaptation strategies for similar fires in the future could benefit by focusing on ignition prevention, fire suppression, and community preparedness, as opposed to fuel treatments that are unlikely to mitigate fire severity during extreme weather. While scientific uncertainties remain regarding the nature of infrequent, high‐severity fires in westside forests, particularly under climate change, adapting to their future occurrence will require different strategies than those in interior, dry forests. [ABSTRACT FROM AUTHOR]

Capillary forces result in the trapping of the oleic phase in porous media even after extensive flushing with brine. Alkali‐surfactant‐polymer formulations drastically diminish capillary forces, whereas adding polymer to the water phase increases viscous forces, resulting in highly efficient extraction of the residual oil. However, by virtue of its scale, the above process requires a large quantity of chemicals, which poses a threat to the environment. Here, we demonstrate that replacing the polymer with a gas such as nitrogen, flue gas, or carbon dioxide achieves equally superior oil extraction efficiency when using a much smaller amount of chemicals. Mobilized oil is first displaced as a continuous phase (oil‐bank) and then as an oil‐in‐water dispersion. Microflow visualization experiments reveal that dispersed oil spreads at the gas–liquid interface (surfactant solutions) due to the presence of adsorbed surfactant molecules. Our dry‐cleaning extraction of hydrocarbons has a wide spectrum of applications and is particularly useful for the production of hydrocarbons from underground formations while mitigating the impact of chemicals on the environment. [ABSTRACT FROM AUTHOR]

This paper analyses the water, the degree of saturation, and the void content effects on the fatigue behaviour of hot mix asphalt (HMA) samples mixed in the laboratory. Some results on stiffness are also given. Fatigue characterization was carried out through a uniaxial tension‐compression (T‐C) test performed in a controlled‐strain mode, at 10°C and 10 Hz, on cylindrical samples. Our results show that the stiffness is not significantly affected by the water. This finding could be attributed to the short period of immersion of samples in water, low testing temperature, low void content of tested samples, and high viscosity of bitumen used. Furthermore, the fatigue resistance of HMA partially saturated with water (PSW) is lower than the one obtained for dry materials. [ABSTRACT FROM AUTHOR]

Objective: To assess the response to topical and/or systemic pilocarpine in dogs with neurogenic dry eye. Method: Medical records of dogs diagnosed with dry eye between 2015 and 2018 were reviewed. Cases were excluded if STT values were decreased bilaterally, if dogs were lost to follow‐up, or if surgical measures (parotid duct transposition) were undertaken within thirty days of presentation. Dogs were on treatment with topical pilocarpine (0.1%, every 6 hours) and/or oral pilocarpine (starting dose 2%, one drop per 10 kg every twelve hours). Results: Eleven cases were included in the study, seven females and four males with mean age of 10 years. Seven cases had xeromycteria, two cases had facial nerve paralysis, and one case had Horner's syndrome. Seven cases (63.6%) had successful outcome following pilocarpine treatment, return to normal STT (15‐25mm/minute), in an average of 24 ± 5.1 days. Of these cases, five had both systemic and topical treatment, one had just topical treatment, and one had just systemic treatment. The average time to normal tear production on treatment with topical pilocarpine ± systemic was 23 days (range 9‐48 days). The number of systemic drops until a positive response varied between individuals from 0.8drops/10kg to 7drops/10kg. Conclusion: Pilocarpine treatment (topical ± systemic) is an effective therapy for unilateral dry eye disease in cases suspected to be neurogenic in origin. Most cases responded within 30 days. Side effects included topical irritation to the ophthalmic solution and systemic effects from oral pilocarpine, such as diarrhea and regurgitation. [ABSTRACT FROM AUTHOR]

In recent decades, energy efficiency has been the priority for masonry buildings in order to keep up with ever more stringent requirements. For the evaluation of the sustainability of building solutions, however, the embodied energy to produce a building and finally to dispose of it at the end of its lifecycle are also important. The energy used for the disposal of a building and the processing of the residues are also important for the overall energy balance since the handling of natural resources is increasingly the centre point of thought and action. A research team at the Chair of Structural Design of TU Dresden has thus been working since 2012 on demountable solutions in masonry, which can be dismantled at the end of a building lifetime and sorted for recycling, which fully complies with the requirement for the reduction of rubbish and waste products. The high precision of block production today permits us to omit the levelling effect of mortar and to build dry buildings in the future, i.e. to do without the bonding principle. The associated strength reductions can be suffered without problems. The appropriate basics of such a dry building method have been researched in a collaboration between the ILEK in Stuttgart and the Xella Technologie‐ und Forschungsgesellschaft mbH in Emstal. In this research project with the abbreviation "REMOMAB", the basics of an energy‐efficient dry building method suitable for recycling were collected and made available for practical application. In a follow‐up project, these basics are being implemented and tested on an experimental building. Cost aspects are also to be taken into account and if possible, construction solutions available on the market will be used – modified if necessary. Another aim is for the first time to dismantle such a building and to rebuild it at another location. This is intended to demonstrate that a reuse is possible after dismantling and such a building method can react to changing demands in the housing market. [ABSTRACT FROM AUTHOR]

ABSTRACT The study investigated the dominant atmospheric circulation patterns associated with abnormal rainfall over Rwanda during the March-May ( MAM) rainfall season in 1981-2010. The data sets used in this study include: rainfall, wind, sea surface temperature ( SST), and humidity. Correlation and composite analysis and Percent of Normal Index ( PNI) were deployed in this study. In the wet years (1987, 1988, and 1998), the country was dominated by moisture convergence, which is in line with wind anomalies that exhibits strong westerly winds from the Atlantic Ocean and southeasterly winds originated from the Indian Ocean. These winds carry moist air mass passing over Congo to the study area, leading to wet events. On the other hand, easterly winds were noted over the study area during the dry years (1984, 2000, 2007, and 2008). The observed wet years coincided with the El Niño events, while the dry years are noted during the La Niña episodes. The dry years exhibited a wide spread of moisture divergence anomaly at the low level and were characterized by the sinking motion as opposed to the wet years with the rising motion. The anomalies of velocity potential/divergence further showed that the wet (dry) years were characterized by convergence (divergence) at the low level. The results also show that there exists a low positive correlation between mean MAM rainfall and SST over the Indian Ocean, which shows minimum influence of the Ocean. On the other hand, it was noted that rainfall amounts is significantly correlated at 95% confidence level with the elevation (altitude) of a given station. This study improves the understanding of the occurrence of wet and dry events in Rwanda, which is helpful in future monitoring of these events. [ABSTRACT FROM AUTHOR]

The present study verified how hydrological regime affects the temporal variability of zooplankton communities in floodplains. Multidimensional methods were employed to characterise community variability, and the temporal trend of the community was also evaluated using a matrices comparison procedure. In connected ponds from the main river, the absence of floods (drought) modified the variability of the zooplankton community by increasing temporal dissimilarity of community. In these environments, the periodic input of water due to floods maintained a lower variability of environmental characteristics, sustaining a lower temporal variability of the community. This observation suggests that, in floodplains, flooding is a component of the system that assists with both the maintenance of ecological processes (temporal variability of the community) and the high biodiversity of these environments. This study therefore suggests that the temporal variability of communities in floodplains is increased by extended droughts, and emphasises the importance of flood dynamics to maintain temporal stability of zooplankton communities in river floodplain systems. [ABSTRACT FROM AUTHOR]

Shape memory effect (SME) was achieved for cellulose-polyurethane (PU) blends of different compositions in wet-dry cycles, featuring that the amorphous cellulose and the PU content served as the fixing phase and the recovery phase, respectively. The dependence on the compositions of the fixity ratio and the recovery ratio was quantitatively measured by tensile tests. The morphological and thermal properties of the blends were further investigated by scanning electron microscopy and thermogravimetric analysis. The storage modulus of the blends varied reversibly in the wet-dry cycles, as determined by dynamic mechanical analysis. Furthermore, the microstructure of the blends reversibly changed correspondingly, as determined by wide-angle X-ray scattering diffraction and Fourier transform infrared. It was predicted that the reversible transition in different amorphous cellulose structures triggered by water led to the reversible variation in modulus as well as the wet-dry SME of the blends. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

Dry environmental conditions induce a variety of skin pathologies and a recent report indicating that cortisol synthesis in epidermis was increased during wound healing led us to hypothesize that environmental dryness might induce increased cortisol secretion in epidermis. Therefore, we incubated a skin equivalent model under dry (relative humidity: less than 10%) and humid (relative humidity: approximately 100%) conditions for 48 hours and evaluated cortisol secretion and mRNA levels of cortisol-synthesizing enzyme (steroid 11β-hydroxylase, CYP11B1) and IL-1β. Cortisol secretion was increased threefold, and CYP11B1 and IL-1β mRNAs were increased 38-fold and sixfold, respectively, in the dry condition versus the humid condition. Occlusion with a water-impermeable plastic membrane partially blocked the increases in cortisol secretion and CYP11B1 and IL-1β mRNA expression in the dry condition. Thus, environmental dryness might induce increased cortisol secretion in epidermis of diseased skin characterized by epidermal barrier dysfunction, potentially influencing mental state and systemic physiology. [ABSTRACT FROM AUTHOR]