Potential benefits of limiting global warming for the mitigation of temperature extremes in China

In this study, we attempt to quantify the potential impacts of two global warming levels (i.e., 1.5 °C and 2.0 °C) on extreme temperature indices across China. The CMIP6 dataset is first evaluated against the CN05.1 observation for the historical period of 1995–2014. Then, future spatiotemporal patterns of changes in extreme temperature at two global warming levels under two shared socio-economic pathway scenarios (SSP245 and SSP585) are further analyzed. Overall, China will experience more frequent and intense high temperature events, such as summer days (SU), tropical nights (TR), warm days (TX90p) and nights (TN90p). On the other hand, under the SSP585, the number of icing days and frost days is projected to decrease at two global warming levels, with the maximal days of decrease (exceeding 20 days) seen in the west of China. Our results suggest that limiting global warming to 1.5 °C rather than 2.0 °C is beneficial to reduce extreme temperature risks. As temperature increases to 1.5 °C and then 2.0 °C above preindustrial levels, the most extreme temperature indices are expected to increase proportionately more during the final 0.5° than during the first 1.5° across most regions of China. For some warm indices, such as the warmest day (TXx), summer days (SU), and warm days (TX90p), the largest incremental changes (from 1.5° to 2.0°) tend to be found in the southwest. Under the SSP585, the incremental changes are similar to the change in the SSP245, but smaller magnitude and spatial extent

Aberrant posterior cingulate connectivity classify first-episode schizophrenia from controls: A machine learning study

Background Posterior cingulate cortex (PCC) is a key aspect of the default mode network (DMN). Aberrant PCC functional connectivity (FC) is implicated in schizophrenia, but the potential for PCC related changes as biological classifier of schizophrenia has not yet been evaluated. Methods We conducted a data-driven approach using resting-state functional MRI data to explore differences in PCC-based region- and voxel-wise FC patterns, to distinguish between patients with first-episode schizophrenia (FES) and demographically matched healthy controls (HC). Discriminative PCC FCs were selected via false discovery rate estimation. A gradient boosting classifier was trained and validated based on 100 FES vs. 93 HC. Subsequently, classification models were tested in an independent dataset of 87 FES patients and 80 HC using resting-state data acquired on a different MRI scanner. Results Patients with FES had reduced connectivity between PCC and frontal areas, left parahippocampal regions, left anterior cingulate cortex, and right inferior parietal lobule, but hyperconnectivity with left lateral temporal regions. Predictive voxel-wise clusters were similar to region-wise selected brain areas functionally connected with PCC in relation to discriminating FES from HC subject categories. Region-wise analysis of FCs yielded a relatively high predictive level for schizophrenia, with an average accuracy of 72.28% in the independent samples, while selected voxel-wise connectivity yielded an accuracy of 68.72%. Conclusion FES exhibited a pattern of both increased and decreased PCC-based connectivity, but was related to predominant hypoconnectivity between PCC and brain areas associated with DMN, that may be a useful differential feature revealing underpinnings of neuropathophysiology for schizophrenia

Enhanced nitrogen removal in constructed wetlands: Effects of dissolved oxygen and step-feeding

Four horizontal subsurface flow constructed wetlands (HSFCWs), named HSFCW1 (three-stage, without step-feeding), HSFCW2 (three-stage, with step-feeding), HSFCW3 (five-stage, without step-feeding) and HSFCW4 (five-stage, with step-feeding) were designed to investigate the effects of dissolved oxygen (DO) and step-feeding on nitrogen removal. High removal of 90.9% COD, 99.1% ammonium nitrogen and 88.1% total nitrogen (TN) were obtained simultaneously in HSFCW4 compared with HSFCW1-3. The excellent TN removal of HSFCW4 was due to artificial aeration provided sufficient DO for nitrification and the favorable anoxic environment created for denitrification. Step-feeding was a crucial factor because it provided sufficient carbon source (high COD: nitrate ratio of 14.3) for the denitrification process. Microbial activities and microbial abundance in HSFCW4 was found to be influenced by DO distribution and step-feeding, and thus improve TN removal. These results suggest that artificial aeration combined with step-feeding could achieve high nitrogen removal in HSFCWs. © 2014 Elsevier Ltd

Enhanced production of intracellular dextran dextrinase from Gluconobacter oxydans using statistical experimental methods

Optimization of the fermentation medium for DDase production by Gluconaobacter oxydans M5 was carried out in the shake flasks using two kinds of statistical methods. Four variables, namely glucose, tryptone, yeast extract and sodium chloride, were found to influence DDase production significantly by the Plackett-Burman screening. A four-factor five-level central composite design (CCD) was chosen to explain the combined effects of the four medium constituents. The optimum medium consisted of glucose (17.670 g/L), maltobiose (30 g/L), tryptone (12.198 g/L), yeast extract (13.528 g/L), ammonium nitrate (15 g/L), copper sulfate (0.01 g/L), zinc sulfate (0.01 g/L), and sodium chloride (0.009 g/L); the initial pH 6.0 was set prior to sterilization. The DDase yield obtained from optimized medium increased by 17-fold (0.238 U/mL) or so. Under these optimal conditions, the experimental values agreed with the predicted values, indicating that the chosen method of optimization of medium composition was efficient, relatively simple, time reducing and material saving

Mechanism for the Pseudoelastic Behavior of FCC Shape Memory Nanowires

Abstract Pseudoelasticity and shape memory have been recently discovered in single-crystalline FCC nanowires of Cu, Ni, Au and Ag. The deformation mechanism responsible for this novel behavior is surface-stress-driven reorientations of the FCC lattice structure. A mechanismbased continuum model has been developed for the lattice reorientation process during loading through the propagation of a single twin boundary. Here, this model is extended to the nucleation, propagation and annihilation of multiple twin boundaries associated with the reverse reorientation process during unloading. The extended model captures the major characteristics of the loading and unloading behavior and highlights the dominating effect of the evolution of twin boundary structure on the pseudoelasticity