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Mechanical metamaterials exhibit interesting properties such as high stiffness at low density1–3, enhanced energy absorption3,4, shape morphing5–7, sequential deformations8–11, auxeticity12–14 and robust waveguiding15,16. Until now, metamaterial design has primarily relied on geometry, and materials nonlinearities such as viscoelasticity, fracture and plasticity have been largely left out of the design rationale. In fact, plastic deformations have been traditionally seen as a failure mode and thereby carefully avoided1,3,17,18. Here we embrace plasticity instead and discover a delicate balance between plasticity and buckling instability, which we term ‘yield buckling’. We exploit yield buckling to design metamaterials that buckle sequentially in an arbitrary large sequence of steps whilst keeping a load-bearing capacity. We make use of sequential yield buckling to create metamaterials that combine stiffness and dissipation—two properties that are usually incompatible—and that can be used several times. Hence, our metamaterials exhibit superior shock-absorption performance. Our findings add plasticity to the metamaterial toolbox and make mechanical metamaterials a burgeoning technology with serious potential for mass production.By not treating plasticity as a mode of failure and instead using it in balance with buckling instability, mechanical metamaterials can be designed that buckle sequentially and show superior shock-absorption performance. [ABSTRACT FROM AUTHOR]

Lactate has a novel function different from previously known functions despite its traditional association with hypoxia in skeletal muscle. It plays various direct and indirect physiological functions. It is a vital energy source within the central nervous system (CNS) and a signal transmitter regulating crucial processes, such as angiogenesis and inflammation. Activating lactate and its associated receptors elicits effects like synaptic plasticity and angiogenesis alterations. These effects can significantly influence the astrocyte-neuron lactate shuttle, potentially impacting cognitive performance. Decreased cognitive function relates to different neurodegenerative conditions, including Alzheimer's disease (AD), ischemic brain injury, and frontotemporal dementia. Therefore, lactic acid has significant potential for treating neurodegenerative disorders. Exercise is a method that induces the production of lactic acid, which is similar to the effect of lactate injections. It is a harmless and natural way to achieve comparable results. Animal experiments demonstrate that high-intensity intermittent exercise can increase vascular endothelial growth factor (VEGF) levels, thus promoting angiogenesis. In vivo, lactate receptor-hydroxycarboxylic acid receptor 1 (HCAR1) activation can occur by various stimuli, including variations in ion concentrations, cyclic adenosine monophosphate (cAMP) level elevations, and fluctuations in the availability of energy substrates. While several articles have been published on the benefits of physical activity on developing Alzheimer's disease in the CNS, could lactic acid act as a bridge? Understanding how HCAR1 responds to these signals and initiates associated pathways remains incomplete. This review comprehensively analyzes lactate-induced signaling pathways, investigating their influence on neuroinflammation, neurodegeneration, and cognitive decline. Consequently, this study describes the unique role of lactate in the progression of Alzheimer's disease. [ABSTRACT FROM AUTHOR]

The goal of this study was to evaluate the performance of a convolutional neural network (CNN) with preoperative MRI and clinical factors in predicting the treatment response of unresectable hepatocellular carcinoma (HCC) patients receiving hepatic arterial infusion chemotherapy (HAIC). A total of 191 patients with unresectable HCC who underwent HAIC in our hospital between May 2019 and March 2022 were retrospectively recruited. We selected InceptionV4 from three representative CNN models, AlexNet, ResNet, and InceptionV4, according to the cross-entropy loss (CEL). We subsequently developed InceptionV4 to fuse the information from qualified pretreatment MRI data and patient clinical factors. Radiomic information was evaluated based on several constant sequences, including enhanced T1-weighted sequences (with arterial, portal, and delayed phases), T2 FSE sequences, and dual-echo sequences. The performance of InceptionV4 was cross-validated in the training cohort (n = 127) and internally validated in an independent cohort (n = 64), with comparisons against single important clinical factors and radiologists in terms of receiver operating characteristic (ROC) curves. Class activation mapping was used to visualize the InceptionV4 model. The InceptionV4 model achieved an AUC of 0.871 (95% confidence interval [CI] 0.761–0.981) in the cross-validation cohort and an AUC of 0.826 (95% CI 0.682–0.970) in the internal validation cohort; these two models performed better than did the other methods (AUC ranges 0.783–0.873 and 0.708–0.806 for cross- and internal validations, respectively; P < 0.01). The present InceptionV4 model, which integrates radiomic information and clinical factors, helps predict the treatment response of unresectable HCC patients receiving HAIC treatment. [ABSTRACT FROM AUTHOR]

Background: Fine particular matter (PM2.5) has been associated with dementia, but limited information is available regarding the association between PM2.5 components and dementia. Aims: We aimed to identify the major components of PM2.5 that affect cognitive function to further investigate its mechanism of action, and develop a prevention strategy for dementia. Methods: In this study, we included 7804 participants aged ≥ 60 years recruited from seven counties in Zhejiang province, eastern China. The participants completed the baseline survey between 2014 and 2015, and were followed up until the end of 2020. We adopted single-component robust Poisson regression models for analyses, and estimated relative risks and 95% confidence intervals describing associations between the chemical constituents of PM2.5 exposure and incident cognitive impairment in those who were free from cognitive impairment at baseline. Results: Significantly positive associations were observed between sulfate, nitrate, ammonium, and organic matter in PM2.5 and incident cognitive impairment across different exposure periods; the relative risks of 10-year exposure before enrollment ranged from 1.01 to 1.02. However, we did not find a significant association between black carbon and cognitive impairment. The point estimates of the relative risk values did not change substantially after performing the sensitivity analyses. Conclusions: Our findings strengthen the idea that long-term exposure to PM2.5 mass and its chemical components is associated with an elevated risk of incident cognitive impairment among older adults. [ABSTRACT FROM AUTHOR]

The identification and detection of various types of explosives are essential for human health and environmental monitoring. Array-based sensing approach offers significant advantages in detecting multi-analytes simultaneously, thereby holding great potential in identifying multiple explosives. Here, we report a tri-channel fluorescence array composed of three distinct fluorescence probes based on gold nanoclusters and nicotinamide adenine dinucleotide with well-separated emission colors. Through the specific interactions of explosives with different fluorescent probes and the yielded response patterns, seven explosives can be successfully distinguished with 100% accuracy. In particular, the sensor array exhibits excellent performance in the quantitative analysis of individual explosive and the differentiation of multiple explosive mixtures. To facilitate the field detection towards practical application, the tri-channel fluorescence array was further integrated with polymer hydrogels. The fabricated portable hydrogel-based array sensors can not only visually identify seven different explosives by their distinct fluorescence color change, but also enable quantitative detection based on linear discriminant analysis (LDA) together with a smartphone. This study illustrates the great potential of hydrogel-based fluorescence sensor array as robust sensors for explosives, which also holds significant promise for the development of portable explosive devices towards practical application. [ABSTRACT FROM AUTHOR]

Due to their responsiveness to modulation by external direct current fields, dielectric tunable materials are extensively utilized in integrated components, such as ferroelectric phase shifters. Barium strontium titanate ceramics have been considered the most potential tunable materials for a long time. However, the significant dielectric loss and high voltage drive have limited their further applications. Recently, Bi6Ti5WO22 ceramic has regained attention for its high dielectric tunability with low loss. In this study, we judiciously introduce Nb5+ with a larger ionic radius, replacing Ti4+ and W6+. This successful substitution enables the modulation of the phase transition temperature of Bi6Ti5WO22 ceramics to room temperature, resulting in superior tunable properties. Specifically, the 0.7Bi6Ti5WO22−0.3Bi6Ti4Nb2O22 ceramics exhibit giant tunability (~75.6%) with ultralow loss (<0.002) under a low electric field (1.5 kV/mm). This tunability is twice that of barium strontium titanate ceramics with a similar dielectric constant and only one-tenth of the loss. Neutron powder diffraction and transmission-electron-microscopy illustrate the nanodomains and micro-strains influenced by ion substitution. Density functional theory simulation calculations reveal the contribution of ion substitution to polarization. The research provides an ideal substitute for tunable material and a general strategy for adjusting phase transition temperature to improve dielectric properties. The authors realize composite optimization in dielectric tunable materials by simultaneously achieving low electric field, large tunability, and low loss through ion substitution design in ferroelectric tunable materials. [ABSTRACT FROM AUTHOR]

Carbo- and heterocycles are frequently used as crucial scaffolds in natural products, fine chemicals, and biologically and pharmaceutically active compounds. Transition-metal-catalyzed cyclization of 1,6-enynes has emerged as a powerful strategy for constructing functionalized carbo- and heterocycles. Despite significant progress, the regioselectivity of alkyne functionalization is entirely substrate-dependent. And only exo-cyclization/cross-coupling products can be obtained, while endo-selective cyclization/cross-coupling remains elusive and still poses a formidable challenge. In this study, we disclose a nickel-catalyzed switchable arylation/cyclization of 1,6-enynes in which the nature of the ligand dictates the regioselectivity of alkyne arylation, while the electrophilic trapping reagents determine the selectivity of the cyclization mode. Specifically, using a commercially available 1,10-phenanthroline as a ligand facilitates trans-arylation/cyclization to obtain seven-membered ring products, while a 2-naphthyl-substituted bisbox ligand promotes cis-arylation/cyclization to access six-membered ring products. Diastereoselective cyclizations have also been developed for the synthesis of enantioenriched piperidines and azepanes, which are core structural elements of pharmaceuticals and natural products possessing important biological activities. Furthermore, experimental and density functional theory studies reveal that the regioselectivity of the alkyne arylation process is entirely controlled by the steric hindrance of the ligand; the reaction mechanism involves exo-cyclization followed by Dowd-Beckwith-type ring expansion to form endo-cyclization products. Divergent functionalizations of pi bonds allow for synthetic chemists to move from simplicity to complexity. Here, the authors report a nickel-catalyzed switchable arylation/cyclization of 1,6-enynes in which the nature of the ligand dictates the regioselectivity of alkyne arylation, while the electrophilic trapping reagents determine the selectivity of the cyclization mode. [ABSTRACT FROM AUTHOR]

Brainbow is a genetic cell-labeling technique that allows random colorization of multiple cells and real-time visualization of cell fate within a tissue, providing valuable insights into understanding complex biological processes. However, fluorescent proteins (FPs) in Brainbow have distinct excitation spectra with peak difference greater than 35 nm, which requires sequential imaging under multiple excitations and thus leads to long acquisition times. In addition, they are not easily used together with other fluorophores due to severe spectral bleed-through. Here, we report the development of a single-wavelength excitable Brainbow, UFObow, incorporating three newly developed blue-excitable FPs. We have demonstrated that UFObow enables not only tracking the growth dynamics of tumor cells in vivo but also mapping spatial distribution of immune cells within a sub-cubic centimeter tissue, revealing cell heterogeneity. This provides a powerful means to explore complex biology in a simultaneous imaging manner at a single-cell resolution in organs or in vivo. UFObow is a single-wavelength excitable Brainbow technique, incorporating three newly developed blue-excitable fluorescent proteins. This method facilitates mapping of immune cells' spatial distribution at a single-cell resolution. [ABSTRACT FROM AUTHOR]

In this study, the (Ni50Mn34.75In15.25)0.9/(Tb0.3Dy0.7Fe1.92)0.1 composites were prepared by spark plasma sintering method, and the influence of different sintering temperatures on the magnetocaloric effect of the composites was studied. For the composite sintered at 923 K, the adiabatic temperature change at a 1.5-T magnetic field is as high as − 2.8 K, and the effective refrigeration capacity at a 5-T magnetic field reaches up to 190 Jkg−1. This is attributed to the fact that internal stresses generated by the magnetostriction of the Tb0.3Dy0.7Fe1.92 particles assist in the magnetic field-driven inverse martensitic transformation and reduce the critical field for phase transition. As the sintering temperature increases to 1023 K, the thermoelastic martensitic transformation characteristic of the composite disappears, which is attributed to the generation of more Fe-rich and In-poor phases in the composite. [ABSTRACT FROM AUTHOR]

Food allergen labelling is an important tool to reduce the risk of exposure to food allergens, especially for highly processed pre-packed snack foods. In order to understand the current status of allergen labelling on pre-packed snack foods in China, this study conducted a stratified random sampling on 9 major categories of pre-packed snack foods in Nanchang, Jiangxi Province, China. 1497 pre-packed snack foods from 15 pre-packed food sale points were collected for information analysis of allergen labelling. It was found that the prevalence of the allergen labelling and precautionary allergen labelling for pre-packed snack foods was 66.93% and 18.77%, respectively, while the overall unqualified rate of the allergen labelling was 29.14%, with the unqualified rate of micro enterprises being as high as 36.88%. This inspires us to strengthen the food safety management concept of food enterprises, accelerate the establishment of mandatory food allergen labelling and standardized management systems in China, and ultimately better protect the health and rights of consumers. [ABSTRACT FROM AUTHOR]

Transition metal-catalyzed asymmetric cyclization of 1,6-enynes is a powerful tool for the construction of chiral nitrogen-containing heterocycles. Despite notable achievements, these transformations have been largely limited to the use of aryl or alkenyl metal reagents, and stereoselective or stereospecific alkylative cyclization of 1,6-enynes remains unexploited. Herein, we report Ni-catalyzed enantioselective reductive anti-arylative cyclization of 1,6-enynes with aryl iodides, providing enantioenriched six-membered carbo- and heterocycles in good yields with excellent enantioselectivities. Additionally, we have realized Ni-catalyzed enantiospecific reductive cis-alkylative cyclization of 1,6-enynes with alkyl bromides, furnishing chiral five-membered heterocycles with high regioselectivity and stereochemical fidelity. Mechanistic studies reveal that the arylative cyclization of 1,6-enynes is initiated by the oxidative addition of Ni(0) to aryl halides and the alkylative cyclization is triggered by the oxidative addition of Ni(0) to allylic acetates. The utility of this strategy is further demonstrated in the enantioselective synthesis of the antiepileptic drug Brivaracetam. Transition metal-catalyzed asymmetric cyclization of 1,6-enynes is a powerful tool for the construction of chiral nitrogen-containing heterocycles, but limiting to the use of aryl or alkenyl metal reagents. Here, the authors report Ni-catalyzed enantioselective anti-arylative cyclization and enantiospecific cis-alkylative cyclization of 1,6-enynes. [ABSTRACT FROM AUTHOR]

Background: Rheumatoid arthritis (RA) is an autoimmune inflammation disease characterized by imbalance of immune homeostasis. p53 mutants are commonly described as the guardian of cancer cells by conferring them drug-resistance and immune evasion. Importantly, p53 mutations have also been identified in RA patients, and this prompts the investigation of its role in RA pathogenesis. Methods: The cytotoxicity of disease-modifying anti-rheumatic drugs (DMARDs) against p53 wild-type (WT)/mutant-transfected RA fibroblast-like synoviocytes (RAFLSs) was evaluated by MTT assay. Adeno-associated virus (AAV) was employed to establish p53 WT/R211* adjuvant-induced arthritis (AIA) rat model. The arthritic condition of rats was assessed by various parameters such as micro-CT analysis. Knee joint samples were isolated for total RNA sequencing analysis. The expressions of cytokines and immune-related genes were examined by qPCR, ELISA assay and immunofluorescence. The mechanistic pathway was determined by immunoprecipitation and Western blotting in vitro and in vivo. Results: Among p53 mutants, p53R213* exhibited remarkable DMARD-resistance in RAFLSs. However, AAV-induced p53R211* overexpression ameliorated inflammatory arthritis in AIA rats without Methotrexate (MTX)-resistance, and our results discovered the immunomodulatory effect of p53R211* via suppression of T-cell activation and T helper 17 cell (Th17) infiltration in rat joint, and finally downregulated expressions of pro-inflammatory cytokines. Total RNA sequencing analysis identified the correlation of p53R211* with immune-related pathways. Further mechanistic studies revealed that p53R213*/R211* instead of wild-type p53 interacted with TANK-binding kinase 1 (TBK1) and suppressed the innate immune TBK1–Interferon regulatory factor 3 (IRF3)–Stimulator of interferon genes (STING) cascade. Conclusions: This study unravels the role of p53R213* mutant in RA pathogenesis, and identifies TBK1 as a potential anti-inflammatory target. [ABSTRACT FROM AUTHOR]

Scaffold diversity is a key feature of a compound library and plays a pivotal role in its success in biological screening. Therefore, it is highly desirable to develop efficient strategies to rapidly construct structurally distinct and diverse "privileged" molecular scaffolds, thereby giving rise to compound libraries with selective and differing biological activities. This review covers recent efforts in this emerging field of Ni-catalyzed divergent and selective synthesis, and will focus on reactions using the same substrate to generate structurally diverse molecular scaffolds by varying the ligand backbone under otherwise almost identical reaction conditions. We hope that the field will be encouraged by the progress achieved, drawing attention to the design and development of new selective catalytic systems, and revealing new modes of catalytic transformation for broader synthetic applications. [ABSTRACT FROM AUTHOR]

The immense potential of lead-free dielectric capacitors in advanced electronic components and cutting-edge pulsed power systems has driven enormous investigations and evolutions heretofore. One of the significant challenges in lead-free dielectric ceramics for energy-storage applications is to optimize their comprehensive characteristics synergistically. Herein, guided by phase-field simulations along with rational composition-structure design, we conceive and fabricate lead-free Bi0.5Na0.5TiO3-Bi0.5K0.5TiO3-Sr(Sc0.5Nb0.5)O3 ternary solid-solution ceramics to establish an equitable system considering energy-storage performance, working temperature performance, and structural evolution. A giant Wrec of 9.22 J cm−3 and an ultra-high ƞ ~ 96.3% are realized in the BNKT-20SSN ceramic by the adopted repeated rolling processing method. The state-of-the-art temperature (Wrec ≈ 8.46 ± 0.35 J cm−3, ƞ ≈ 96.4 ± 1.4%, 25–160 °C) and frequency stability performances at 500 kV cm−1 are simultaneously achieved. This work demonstrates remarkable advances in the overall energy storage performance of lead-free bulk ceramics and inspires further attempts to achieve high-temperature energy storage properties. One of the key challenges in dielectric ceramics for energy storage lies in the comprehensive optimization of their properties. Here, the authors establish an equitable system considering performance and structure evolution in a lead-free ceramic capacitor, achieving a broad-high temperature performance. [ABSTRACT FROM AUTHOR]

In recent years, the prevalence of allergic diseases has increased significantly, causing great concern, and wheat, as one of the top 8 food allergens, is a common allergy trigger. Nevertheless, reliable estimates of the positivity rate of wheat allergens in the allergic population in China are still lacking. The systematic review and meta-analysis aims to evaluate the positive detection rate of wheat allergens in the Chinese allergic population and further provide a reference for the prevention of allergy. CNKI, CQVIP, WAN-FANG DATA, Sino Med, PubMed, Web of Science, Cochrane Library, and Embase databases were retrieved. Related research and case reports about the positive rate of wheat allergen in the Chinese allergic population published from inception to June 30, 2022, were searched, and meta-analysis was performed using Stata software. The pooled positive rate of wheat allergens and 95% confidence interval were calculated by random effect models, and the publication bias was evaluated using Egger's test. A total of 13 articles were included for the final meta-analysis, in which wheat allergen detection methods involved only serum sIgE testing and SPT assessment. The results showed that the wheat allergen positivity detection rate in Chinese allergic patients was 7.30% (95% CI 5.68–8.92%). Subgroup analysis showed that the positivity rate of wheat allergens was influenced by region, but hardly by age and assessment method. The positive rates of wheat allergy in the population with allergic diseases were 2.74% (95% CI 0.90–4.58%) and 11.47% (95% CI 7.08–15.87%) in southern and northern China, respectively. In particular, the positive rates of wheat allergens were greater than 10% in Shaanxi, Henan and Nei Mongol, all of which belong to the northern region. These results suggest that wheat allergens are an important cause of sensitization in allergic populations from northern China, and therefore attention should be paid to early prevention in high-risk populations. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) play a critical role in the regulation of atherosclerosis. Here, we investigated the role of the lncRNA growth arrest-specific 5 (lncR-GAS5) in atherogenesis. We found that the enforced expression of lncR-GAS5 contributed to the development of atherosclerosis, which presented as increased plaque size and reduced collagen content. Moreover, impaired autophagy was observed, as shown by a decreased LC3II/LC3I protein ratio and an elevated P62 level in lncR-GAS5-overexpressing human aortic endothelial cells. By contrast, lncR-GAS5 knockdown promoted autophagy. Moreover, serine/arginine-rich splicing factor 10 (SRSF10) knockdown increased the LC3II/LC3I ratio and decreased the P62 level, thus enhancing the formation of autophagic vacuoles, autolysosomes, and autophagosomes. Mechanistically, lncR-GAS5 regulated the downstream splicing factor SRSF10 to impair autophagy in the endothelium, which was reversed by the knockdown of SRSF10. Further results revealed that overexpression of the lncR-GAS5-targeted gene miR-193-5p promoted autophagy and autophagic vacuole accumulation by repressing its direct target gene, SRSF10. Notably, miR-193-5p overexpression decreased plaque size and increased collagen content. Altogether, these findings demonstrate that lncR-GAS5 partially contributes to atherogenesis and plaque instability by impairing endothelial autophagy. In conclusion, lncR-GAS5 overexpression arrested endothelial autophagy through the miR-193-5p/SRSF10 signaling pathway. Thus, miR-193-5p/SRSF10 may serve as a novel treatment target for atherosclerosis. [ABSTRACT FROM AUTHOR]

Diabetes mellitus, associated with α-glucosidase, has been considered as a chronic metabolic disorder, seriously affecting human health. Thus, searching natural α-glucosidase inhibitors and investigating their inhibition mechanism are urgently important. In this study, sixty-two essential oils (EOs), derived from aromatic plants, were found to exert different inhibition on α-glucosidase. The further study revealed that the most potent EOs against α-glucosidase were chuan-xiong, fructus cnidii, sacha inchi, aloe, ganoderma lucidum spore and ginger with IC50 values of 3.02, 2.88, 7.37, 5.06, 5.32 and 7.40 μg/mL. Moreover, the inhibitory mechanism and kinetics studies found that chuan-xiong and sacha inchi were reversible and mixed-type inhibitors. Fructus cnidii, aloe, ganoderma lucidum spore and ginger were reversible and uncompetitive-type inhibitors. It is suggested that EOs, being of natural origin, would be promising anti-α-glucosidase agents. [ABSTRACT FROM AUTHOR]

cAMP is a key second messenger that regulates diverse cellular functions including neural plasticity. However, the spatiotemporal dynamics of intracellular cAMP in intact organisms are largely unknown due to low sensitivity and/or brightness of current genetically encoded fluorescent cAMP indicators. Here, we report the development of the new circularly permuted GFP (cpGFP)-based cAMP indicator G-Flamp1, which exhibits a large fluorescence increase (a maximum ΔF/F0 of 1100% in HEK293T cells), decent brightness, appropriate affinity (a Kd of 2.17 μM) and fast response kinetics (an association and dissociation half-time of 0.20 and 0.087 s, respectively). Furthermore, the crystal structure of the cAMP-bound G-Flamp1 reveals one linker connecting the cAMP-binding domain to cpGFP adopts a distorted β-strand conformation that may serve as a fluorescence modulation switch. We demonstrate that G-Flamp1 enables sensitive monitoring of endogenous cAMP signals in brain regions that are implicated in learning and motor control in living organisms such as fruit flies and mice. The second messenger cAMP modulates a wide range of important biological processes. Here, the authors developed a fluorescent indicator termed G-Flamp1, which can accurately report levels of cAMP in living cells. [ABSTRACT FROM AUTHOR]

Climate change is expected to profoundly affect key food production sectors, including fisheries and agriculture. However, the potential impacts of climate change on these sectors are rarely considered jointly, especially below national scales, which can mask substantial variability in how communities will be affected. Here, we combine socioeconomic surveys of 3,008 households and intersectoral multi-model simulation outputs to conduct a sub-national analysis of the potential impacts of climate change on fisheries and agriculture in 72 coastal communities across five Indo-Pacific countries (Indonesia, Madagascar, Papua New Guinea, Philippines, and Tanzania). Our study reveals three key findings: First, overall potential losses to fisheries are higher than potential losses to agriculture. Second, while most locations (> 2/3) will experience potential losses to both fisheries and agriculture simultaneously, climate change mitigation could reduce the proportion of places facing that double burden. Third, potential impacts are more likely in communities with lower socioeconomic status. Responses of agriculture and fisheries to climate change are interlinked, yet rarely studied together. Here, the authors analyse more than 3000 households from 5 tropical countries and forecast mid-century climate change impacts, finding that communities with higher fishery dependence and lower socioeconomic status communities face greater losses. [ABSTRACT FROM AUTHOR]

Direct ink writing (DIW) has recently emerged as an appealing method for designing and fabricating three-dimensional (3D) objects. Complex 3D structures can be built layer-by-layer via digitally controlled extrusion and deposition of aqueous-based colloidal pastes. The formulation of well-dispersed suspensions with specific rheological behaviors is a prerequisite for the use of this route. In this review article, the fundamental concepts of DIW are presented, including the operation principles and basic features. Typical strategies used for ink formulation are discussed with a focus on the most widely used electrode materials, including graphene, Mxenes, and carbon nanotubes. The recent progress in printing design of emerging energy storage systems, encompassing rechargeable batteries, supercapacitors, and hybrid capacitors, is summarized. Challenges and future perspectives are also covered to provide guidance for the future development of DIW. [ABSTRACT FROM AUTHOR]

The present work investigated the effects of the zeolite 4A on the flame retardancy and thermal stability of aluminum β-(p-nitrobenzamide) ethyl methyl phosphinate (AlNP) in acrylonitrile–butadiene–styrene copolymer (ABS). The synergistic effect between AlNP and zeolite 4A was assessed with cone calorimeter test (CCT), thermogravimetric measurement (TG), Fourier transform infrared spectroscopy (FTIR) analysis of the gaseous products, and scanning electron microscopy (SEM) characterization of the residues char. Keep the total loading of the additives at 25 wt.%; ABS filled with 22 wt.% AlNP and 3 wt.% zeolite 4A (ABS-AlNP22-A3) reaches a UL94 V0 classification with LOI value of 29.3%. By comparison, ABS with 25 wt.% AlNP alone (ABS-AlNP25) only passes the UL 94 V 1 rating with LOI value of 26.0%. CCT results verify that the zeolite 4A can depress the heat and smoke release of combustion. The peak heat release rate, total heat release, and total smoke release of ABS-AlNP22-A3 are reduced by 13.84%, 14.35%, and 20.4%, respectively, compared to ABS-AlNP25. The TG/FTIR analysis and morphology of the char residues from scanning electron microscopy further demonstrate that zeolite 4A could retard the volatilization of hydrocarbons and promote the char formation in the combustion process of ABS. The mechanism of synergistic effect of the zeolite 4A is proposed based on the experiment and related previous study. [ABSTRACT FROM AUTHOR]

Protein prenylation is a post-translational lipid modification that governs a variety of important cellular signaling pathways, including those regulating synaptic functions and cognition in the nervous system. Two enzymes, farnesyltransferase (FT) and geranylgeranyltransferase type I (GGT), are essential for the prenylation process. Genetic reduction of FT or GGT ameliorates neuropathology but only FT haplodeficiency rescues cognitive function in transgenic mice of Alzheimer's disease. A follow-up study showed that systemic or forebrain neuron-specific deficiency of GGT leads to synaptic and cognitive deficits under physiological conditions. Whether FT plays different roles in shaping neuronal functions and cognition remains elusive. This study shows that in contrast to the detrimental effects of GGT reduction, systemic haplodeficiency of FT has little to no impact on hippocampal synaptic plasticity and cognition. However, forebrain neuron-specific FT deletion also leads to reduced synaptic plasticity, memory retention, and hippocampal dendritic spine density. Furthermore, a novel prenylomic analysis identifies distinct pools of prenylated proteins that are affected in the brain of forebrain neuron-specific FT and GGT knockout mice, respectively. Taken together, this study uncovers that physiological levels of FT and GGT in neurons are essential for normal synaptic/cognitive functions and that the prenylation status of specific signaling molecules regulates neuronal functions. [ABSTRACT FROM AUTHOR]

Irrigation is the largest sector of human water use and an important option for increasing crop production and reducing drought impacts. However, the potential for irrigation to contribute to global crop yields remains uncertain. Here, we quantify this contribution for wheat and maize at global scale by developing a Bayesian framework integrating empirical estimates and gridded global crop models on new maps of the relative difference between attainable rainfed and irrigated yield (ΔY). At global scale, ΔY is 34 ± 9% for wheat and 22 ± 13% for maize, with large spatial differences driven more by patterns of precipitation than that of evaporative demand. Comparing irrigation demands with renewable water supply, we find 30–47% of contemporary rainfed agriculture of wheat and maize cannot achieve yield gap closure utilizing current river discharge, unless more water diversion projects are set in place, putting into question the potential of irrigation to mitigate climate change impacts. There are big uncertainties in the contribution of irrigation to crop yields. Here, the authors use Bayesian model averaging to combine statistical and process-based models and quantify the contribution of irrigation for wheat and maize yields, finding that irrigation alone cannot close yield gaps for a large fraction of global rainfed agriculture. [ABSTRACT FROM AUTHOR]

This paper uses the finite element method for numerical simulation and builds a transient global model to simulate polycrystalline silicon ingot growing process in CGsim software. The transient global model is verified through experiments. In addition, the influence of the width and height of the bottom of the side insulation on the temperature field, power consumption and melt-crystal interface (m/c interface) of the solidification process are analyzed. And a new hot zone design method is proposed to protect seed crystal silicon. The results show that the residual height of the seed crystal is increased by 4.5 mm through this design. And increasing the width and height of the side insulation bottom can effectively reduce the power consumption by 5 kW and improve the crystal growth interface, which helps to improve the crystal quality and reduce the cost. This study will provide some references for the optimization of polycrystalline silicon ingot growing process. [ABSTRACT FROM AUTHOR]

A change in soil temperature (ST) is a significant indicator of climate change, so understanding the variations in ST is required for studying the changes of the Qinghai–Tibet Plateau (QTP) permafrost. We investigated the performance of three reanalysis ST products at three soil depths (0–10 cm, 10–40 cm, and 40–100 cm) on the permafrost regions of the QTP: the European Centre for Medium-Range Weather Forecasts interim reanalysis (ERA-Interim), the second version of the National Centers for Environmental Prediction Climate Forecast System (CFSv2), and the Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2). Our results indicate that all three reanalysis ST products underestimate observations with negative mean bias error values at all three soil layers. The MERRA-2 product performed best in the first and second soil layers, and the ERA-Interim product performed best in the third soil layer. The spatiotemporal changes of annual and seasonal STs on the QTP from 1980 to 2017 were investigated using Sen's slope estimator and the Mann–Kendall test. There was an increasing trend of ST in the deeper soil layer, which was less than that of the shallow soil layers in the spring and summer as well as annually. In contrast, the first-layer ST warming rate was significantly lower than that of the deeper soil layers in the autumn and winter. The significantly (P < 0.01) increasing trend of the annual ST indicates that the QTP has experienced climate warming during the past 38 years, which is one of the factors promoting permafrost degradation of the QTP. [ABSTRACT FROM AUTHOR]

A simple route to synthesize the polyaniline (PANI) nanofibers with diameter about 150 nm was reported. In this strategy, the PANI nanofibers were fabricated by electrochemical deposition by using two-electrode configuration in 0.01 M aniline and 0.01 M H2SO4 electrolytes. The as-prepared materials were characterized by scanning electron microscopy (SEM), infrared spectroscopy (FTIR), Raman spectroscopy and thermogravimetric analysis (TGA). The electrochemical properties of the PANI nanofibers electrode as supercapacitor materials were investigated. The PANI nanofibers electrode showed high capacitance of 485 F·g-1 at 0.1 A·g-1, and the decrease in the specific capacitance is about 3.5% in 1 000 cycles. The results indicate that the PANI nanofibers electrode shows high stability and retains its electrochemical capacitance property over 1 000 cycles, suggesting PANI nanofibers have promising applications in high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

The role of alkali metal elements in ZnO varistor is of interest because of the small ion radius and valence state. They are expected to form acceptor state and convert the n-type ZnO grain to p-type. However, researches to manufacture p-type ZnO semi-donductor by using alkali metal elements have failed. In the present work, the effects of lithium element on the defect structures, microstructures and corresponding electrical performances of ZnO varistors is investigated. According to the obtained results, the influences of lithium element on the defect structures of ZnO varistors will vary with the amount of lithium. Lithium ion occupies the interstitial site of ZnO grain at first and then occupies the substitutional site. Trace amount of lithium (0.0005-0.002 wt%) can reduce the residual voltage of ZnO varistors while the E-J characteristics at low current region remain stable. [ABSTRACT FROM AUTHOR]

Under the impacts of climate variability and human activities, there is violent fluctuation for streamflow in the large basins in China. Therefore, it is crucial to separate the impacts of climate variability and human activities on streamflow fluctuation for better water resources planning and management. In this study, the Three Rivers Headwater Region (TRHR) was chosen as the study area. Long-term hydrological data for the TRHR were collected in order to investigate the changes in annual runoff during the period of 1956-2012. The nonparametric Mann-Kendall test, moving t test, Pettitt test, Mann-Kendall-Sneyers test, and the cumulative anomaly curve were used to identify trends and change points in the hydro-meteorological variables. Change point in runoff was identified in the three basins, which respectively occurred around the years 1989 and 1993, dividing the long-term runoff series into a natural period and a human-induced period. Then, the hydrologic sensitivity analysis method was employed to evaluate the effects of climate variability and human activities on mean annual runoff for the human-induced period based on precipitation and potential evapotranspiration. In the human-induced period, climate variability was the main factor that increased (reduced) runoff in LRB and YARB (YRB) with contribution of more than 90 %, while the increasing (decreasing) percentage due to human activities only accounted for less than 10 %, showing that runoff in the TRHR is more sensitive to climate variability than human activities. The intra-annual distribution of runoff shifted gradually from a double peak pattern to a single peak pattern, which was mainly influenced by atmospheric circulation in the summer and autumn. The inter-annual variation in runoff was jointly controlled by the East Asian monsoon, the westerly, and Tibetan Plateau monsoons. [ABSTRACT FROM AUTHOR]

Climate change has great impacts on hydrological processes worldwide. The Tibetan Plateau (TP), the 'Water Tower' of Asia, poses significant influences on Asian climate and is also one of the most sensitive areas to climate change. Therefore, it is of importance to investigate the plausible future hydrological regimes in the TP based on the climate scenarios provided by General Circulation Models (GCMs). In this study, the Variable Infiltration Capacity model was coupled with Shuffled Complex Evolution developed at the University of Arizona to explore the responses of hydrological processes to climate change in the Lhasa River basin, the tributary of the Yarlung Zangbo River in the southern TP. A downscaling framework based on Automatic Statistical Downscaling was used to generate the future climate data from two GCMs (Echam5 and Miroc3.2_Medres) under three scenarios (A1B, A2 and B1) for the period of 2046-2065. Results show increases for both air temperature and annual precipitation in the future climate. Evaporation, runoff and streamflow will experience a rising trend, whereas spring snow cover will reduce dramatically. These changes present significant spatial and temporal variations. The alteration of hydrological processes may challenge the local water resource management. This study is helpful for policy makers to tackle climate change related issues in terms of mitigation and adaptation. [ABSTRACT FROM AUTHOR]

The effect of sintering temperature (ranging from 1055 to 1200 °C) on the phase ingredient and dielectric property of the nominal BaTiO ceramics (starting with the Ba/Ti of 1:2) fabricated by a spark plasma sintering method were systematically studied. At the first stage, BaTiO component was enhanced in the sintering temperature range of 1055-1120 °C; it turned out to be the dominant phase. For these BaTiO phase dominated ceramics, the Curie temperature T rised on increasing the sintering temperature and saturated around 440 °C with the maximum dielectric constant of 500. Further increasing the sintering temperature, the decomposition of the obtained BaTiO into BaTiO extensively happened; the ceramics turned to be the BaTiO and BaTiO coexisting state. These ceramics can be characterized by two dielectric anomalies. One at ~420 °C stood for the phase transition of BaTiO while the other at ~150 °C stood for the transition of BaTiO, which is exceptionally high as the normal BaTiO ceramics. Further increasing the sintering temperature (until 1200 °C) would dramatically enhance the BaTiO phase; the ceramics showed T at 130 °C with the maximum dielectric constant of 1800. [ABSTRACT FROM AUTHOR]

In this study, we investigated an acute outbreak of porcine hemagglutinating encephalomyelitis on a farm of 127 pigs in Jilin province, China. Porcine hemagglutinating encephalomyelitis virus (PHEV) was detected in suckling and weaning pigs by RT-PCR assays. Coronavirus-like particles were observed by electron microscopy. The virus isolate was designated PHEV-JT06. The clinical signs, nervous symptoms and positive labeling of neurons in the cerebral cortex with an immunohistochemical stain in PHEV-JT06-infected BALB/c mice supported the diagnosis of PHEV infection. The five full-length PHEV-JT06 structural genes were cloned, sequenced and analyzed. Phylogenetic studies based on the nucleotide and amino acid sequences of the five genes in the outbreak showed that PHEV remained genetically stable. PHEV shares 95.3-99.3 % amino acid sequence identity with American strains (AY078417), suggesting that the Chinese isolate is most likely derived from the North American strain. Additionally, PHEV, HCoV-OC43 and BCoV were genetically close. These results may provide some insights into the genotype of the etiological agent responsible for the porcine hemagglutinating encephalomyelitis outbreak and could also provide a comparative view of the genomics of the five structural proteins of PHEV. [ABSTRACT FROM AUTHOR]

The Tibetan Plateau (TP) is the 'water tower of Asia' and it plays a key role on both hydrology and climate for southern and eastern Asia. It is critical to explore the impact of climate change on runoff for better water resources management in the TP. However, few studies pay attention to the runoff response to climate change in large river systems on the TP, especially in data-sparse upstream area. To complement the current body of work, this study uses two rainfall-runoff models (SIMHYD and GR4J) to simulate the monthly and annual runoff in the upstream catchments of the Yarlung Tsangpo River basin (YTR) under historical (1962-2002) and future (2046-2065 A1B scenario) climate conditions. The future climate series are downscaled from a global climate model (MIROC3.2_hires) by a high resolution regional climate model (RegCM3). The two rainfall-runoff models successfully simulate the historical runoff for the eight catchments in the YTR basin, with median monthly runoff Nash-Sutcliffe Efficiency of 0.86 for SIMHYD and 0.83 for GR4J. The mean annual future temperature in eight catchments show significant increase with the median of +3.8 °C. However, the mean annual future precipitation shows decrease with the median of −5.8 % except in Lhatse (+2.0 %). The two models show similar modeling results that the mean annual future runoff in most of catchments (seven in eight) shows decrease with the median of −13.9 % from SIMHYD and −15.2 % from GR4J. The results achieved in this study are not only helpful for local water resources management, but also for future water utilization planning in the lower reaches region of the Brahmaputra. [ABSTRACT FROM AUTHOR]

Dense BaTiO are fabricated from the conventional calcined powder by using spark plasma sintering and by adding MnO as a dopant. The effects of the sintering temperature and the amount of MnO on the phase purity are symmetrically investigated. A pure BaTiO phase is obtained under a condition with the sintering temperature of 1,055 °C and the amount of MnO doping of 0.2 wt% from the conventional powder calcined at 950 °C. The relative density of that ceramics is 98 %. The temperature dependence of dielectric property shows the Curie temperature ( T) of 446 °C with the peak value of 450. Besides, the ceramics polarization of 0.63 μC/cm and the coercive field of 2.0 kV/cm at room temperature, respectively. [ABSTRACT FROM AUTHOR]

Land cover is closely related to environmental changes and socioeconomic development. Land-cover change in the Tibetan Plateau (TP) is different from that in the lowlands; however, a detailed land-cover change in areas such as the Yarlung Tsangpo River (YTR) basin in the TP has not been reported. To fill this gap, the current study explores the land-cover change between 1985 and 2005 in the YTR basin. The results show that only 1 % of the land cover in the YTR basin changed during this time period. The most significant land-cover changes included increases in forest and built-up areas as well as decreases in grassland, water and wetland areas. By percentage, the most rapid land-cover change occurred for built-up areas with an annual variation of 2.07 %. There was an obvious vertical distribution pattern for land-cover types in the YTR basin; from low to high, the average altitudes were forest, farmland, built-up, grassland, water and wetland, and bare land. The average altitude and slope for most land-cover types did not vary over the past 20 years. However, the average altitude and slope of built-up significantly decreased, especially in the zone between 3,500 and 4,000 m. The water and wetland area in altitudes above 4,500 m increased; however, they decreased in the zone between 3,500 and 4,000 m. Natural factors cause most land-cover changes, whereas the increasing intensity of human activities cause some changes to built-up and farmland. Additional attention should be paid to the study of the mechanism of land-cover change in the TP. [ABSTRACT FROM AUTHOR]

For finite-dimensional quantum systems, we propose a quantum control scheme based on a multi-step unitary evolution and quantum projective measurements. The objective is to design a control law to steer the system to a target eigenstate of the measurement operator in the least number of steps. Within each control step, unitary evolution and quantum projective measurement are performed in turn until the system reaches the target state. The control process can be modeled as a finite-state Markov chain with an absorbing state. We prove that the controlled system will converge to the target eigenstate with probability one after a finite number of control steps and find a minimal-step-number condition that would steer the system to the target eigenstate in the least number of steps. [ABSTRACT FROM AUTHOR]

Glucose-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49) was purified from the leaves of 8-week-old Populus suaveolens cuttings. The enzyme activity in the absence and presence of reduced dithiothreitol (DTTred) was determined. The results show that the G6PDH activity is not inactivated by pre-incubation with DTTred, indicating that the purified enzyme probably presented in cytosol of P. suaveolens. The catalytic characteristics and kinetic parameters of cytosolic G6PDH purified from P. suaveolens cuttings were also studied. The results show that G6PDH is characterized by K m value of 360 µmol·L−1 for G6P and 16 µmol·L−1 for NADP, a pH range of 7.3-8.9, and the maximum activity around pH 8.2. The enzyme activity is inhibited by various metabolites such as NADPH, NADH, GTP, UTP, ATP, AMP, ADP, CoA, acetyl CoA, fructose-6-phosphate (F6P), erythrose-4-phosphate (E4P), ribose-5-phosphate (R5P) and 3-phosphoglycerate (3-PG) (all at 1 mmol·L−1 except for NADPH and NADH) to different extents. NADPH is the most effective inhibitor of enzyme activity, with an inhibition of 72.0%. The addition of metal ions such as MgCl2, CaCl2 and KCl (all 1.0 mmol·L−1) to the standard reaction mixture has no remarkable influence on the cytosolic G6PDH activity. However, CdCl2 (1.0 mmol·L−1) causes high inhibitory effect on the enzyme activity. To explore the role of G6PDH on the enhancement of freezing resistance induced by freezing acclimation, the changes in the cytosolic G6PDH activity and freezing resistance (expressed as LT50) of P. suaveolens cuttings during freezing acclimation at −20 °C were investigated. The results reveal that freezing acclimation decreases LT50 of cuttings, and increases the activity of cytosolic G6PDH compared with control ones, while 2 d of de-acclimation at 25 °C result in a decrease in cytosolic G6PDH activity, and caused an increase in LT50. Furthermore, the change in cytosolic G6PDH activity is found to be closely correlated to the degree of freezing resistance of cuttings during freezing acclimation. It is suggested that cytosolic G6PDH may be involved in the induction of freezing resistance of cuttings. [ABSTRACT FROM AUTHOR]

To explore the physiological and biochemical mechanism of the occurrence of vitrified shoots of Populus suaveolens in tissue culture, the changes in water, chlorphyll, lignin, H2O2, phenylalanine ammonialyase (PAL), malonaldehyde (MDA), protective enzymatic systems, and some key enzymes involved in the ascorbate- glutathione cycle were comparatively studied in both normal and vitrified shoots of P. suaveolens. The results show that the lower activities of peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), glutathione reductase (GR) and PAL, and the less contents of chlorphyll, lignin, ascorbate (ASA) and reduced glutathione (GSH) as well as the lower ratios of ASA / DHA and GSH / GSSG are observed in vitrified shoots than in normal ones during the whole culture period. While in comparison with normal shoots, the higher activity of superoxide dismutase (SOD) and the more concentrations of water, H2O2, MDA, dehydroascorbate (DHA) and oxidized glutathione (GSSG) are found in vitrified shoots. Statistical analysis indicates that the enhanced activity of SOD and the decreased activities of CAT and POD as well as some enzymes involved in the ascorbate-glutathione cycle might be closely correlated to the accumulation of H2O2. The less regeneration of ASA and GSH and the lower capacity of the ascorbate-glutathione cycle observed in vitrified shoots might be due to a significant decrease in APX, MDAR, DHAR and GR activities and a decline in redox status of ASA and GSH. The decreases in chlorphyll content might result in a decline in photosynthesis. The lower activities of POD and PAL could result in the decrease of lignin synthesis and cell wall ligination, which might be the key factor leading to the increase in water content. It is concluded that the deficiency of detoxification capacity caused by the lower capacity of the ascorbate-glutathione pathway and the decreased activity of protective enzymatic system might lead to the large accumulation of H2O2 and the enhancement of membrane lipid peroxidation, which might be the main cause leading to the occurrence of vitrifying shoots of P. suaveolens in tissue culture. [ABSTRACT FROM AUTHOR]

The Global Gridded Crop Model Intercomparison (GGCMI) phase 1 dataset of the Agricultural Model Intercomparison and Improvement Project (AgMIP) provides an unprecedentedly large dataset of crop model simulations covering the global ice-free land surface. The dataset consists of annual data fields at a spatial resolution of 0.5 arc-degree longitude and latitude. Fourteen crop modeling groups provided output for up to 11 historical input datasets spanning 1901 to 2012, and for up to three different management harmonization levels. Each group submitted data for up to 15 different crops and for up to 14 output variables. All simulations were conducted for purely rainfed and near-perfectly irrigated conditions on all land areas irrespective of whether the crop or irrigation system is currently used there. With the publication of the GGCMI phase 1 dataset we aim to promote further analyses and understanding of crop model performance, potential relationships between productivity and environmental impacts, and insights on how to further improve global gridded crop model frameworks. We describe dataset characteristics and individual model setup narratives. Design Type(s) modeling and simulation objective • data integration objective • software variation design • time series design Measurement Type(s) cultivated environment Technology Type(s) computational modeling technique Factor Type(s) crop • atmospheric weather • atmospheric wind speed • atmospheric water vapour • atmospheric carbon dioxide • agricultural environmental material • agricultural feature Sample Characteristic(s) land Machine-accessible metadata file describing the reported data (ISA-Tab format) [ABSTRACT FROM AUTHOR]

Flashover is a crucial issue in both high-voltage engineering and surface physics. It not only challenges the existing theories about its dynamic evolution, but also inhibits the clean energy revolution by limiting the accessible voltage rating of power equipment. It is of significance to elucidate the microscopic process along the interface to improve the flashover performance. In the present study, the synergic effect of adsorbed gas and surface charging is investigated, which reveals a long ignored factor for determining the flashover voltage. Depending on the relative amount of adsorbed gas, the flashover voltage varies, which exhibit different behavior from the bulk breakdown of the same gas. The amount of N2 gas adsorbed on epoxy resin (EP) surface is much larger than that on Al2O3 ceramic surface, corresponding to the observed higher flashover voltage on EP. It is proposed that the adsorbed gas molecules not only modify the local surface charging state via their interaction with the trapped charges, but also capture free electrons due to the distortion of their electronic distribution. Both effects suppress the free path length of electrons in the gas-solid interface. This work explores another possibility to improve the surface flashover performance. [ABSTRACT FROM AUTHOR]