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Reservoir computing (RC) is a computational architecture capable of efficiently processing temporal information, which allows low-cost hardware implementation. However, the previously reported memristor-based RC mostly utilized binarized data sets to reduce the difficulty of signal processing of the memristor, which inevitably induces data distortion to a certain extent, leading to poor network computing performance. Here, we report on a RC system in a fully memristive architecture based on solution-processed perovskite memristors. The perovskite memristor exhibits 10000 conductance states with a modulation range of more than 4 orders of magnitude. The obtained tens of thousands of finely spaced conductance states with a near-ideal analog property provide a sufficiently large dynamic range and enough intermediate states, which were further applied as a reservoir to map the feature information on different sequential inputs in an analog way. The computing capability of the image classification task of a Fashion-MNIST data set with a high recognition accuracy of up to 90.1% shows that the excellent analog and short-term properties of our perovskite memristor allow the hardware implementation of neuromorphic computing with a reduced training cost.

Two primitive metal-organic frameworks (MOFs), NiL1 and NiL2, based on Ni8O6-cluster and ditopic pyrazolate linkers, L1 (with rigid alkyne arms) and L2 (with flexible alkyne chains), were prepared. The proton conductivities of these MOFs in pristine form and imidazole-encapsulated forms, Im@NiL1 and Im@NiL2, were measured and compared. Upon introduction of imidazole molecules, the proton conductivity could be increased by 3 to 5 orders of magnitude and reached as high as 1.72 × 10−2 S/cm (at 98% RH and 80 °C). Also, whether imidazole molecules were introduced or not, Ni8O6-MOFs with L2 in general gave better proton conductivity than those with L1 signifying that flexible side arms indeed assist proton conduction probably via establishment of efficient proton-conducting channels along with formation of highly ordered domains of water/imidazole molecules within the network cavities. Beyond the active Ni8O6-cluster, tuning flexibility of linker pendants serves as an alternative approach to regulate/modulate the proton conductivity of MOFs.

Objectives: This study explores the specialized nursing requirements of different clinical departments and their influence on the design of nursing units, which ultimately improves the nursing staff’s efficiency and work experience. Background: Specialization of nursing work is important in the provision of quality of healthcare. Most of the research related to nursing units has focuses on general medical–surgical nursing units and has not differentiated between clinical departments. Method: This study was conducted in one inpatient building at a large general hospital in China. Survey data were collected from 11 clinical departments via questionnaire, and interviews were conducted in 10 of the clinical departments. Results: All 11 clinical departments had significant differences in their evaluations of and requirements for the arrangement of their physical space. Specialized requirements were found in three areas: nursing work processes, arrangement and needs of clinical spaces, and allocation of facilities and equipment. Conclusion: Evaluation of the specialized requirements of different clinical departments would contribute to the body of knowledge on nursing unit design and has a positive effect on the development and improvement of design theory. Suggestions for how the design of nursing units could be improved to support the specialized demands of different departments are provided.

Memory and synaptic devices based on three IDTT-based copolymers were investigated.

Exploitation of bamboo-derived biochar offers a lucrative opportunity for using moso bamboo due to its short growth cycle, large quantity and universality.

The innovative exploration of the floating body effect in a 2D WSe2 dual-gate transistor for the potential implementation of single-transistor capacitor-less dynamic random access memory.

Vitrimer based moist-electric generators that produce high and sustained voltage outputs at high temperature and high moisture conditions, and simultaneously exhibit outstanding mechanical properties and excellent self-healing ability.

Vegetation phenology changes are able to reveal climate-change-associated ecosystem feedback mechanisms. In this study, Qinghai–Tibet Plateau (QTP) alpine vegetation phenological information was extracted from the normalised difference vegetation index of the MOD13Q1 product collected from 2001 to 2020 using TIMESAT3.3 and S-G filtering and threshold dynamics methods. An analysis of data from the start of growth (SOG) and end of growth (EOG) seasons using a Theil–Sen median slope trend and partial correlation analyses revealed spatial and temporal variations in vegetation phenology related to climate change and topography, including: (1) significant spatial variation, gradually increasing southeast-to-northwest SOG delays and northeast-to-southwest EOG delays, with significant variations across vegetation types; (2) significant altitude-associated variations in the meadow, steppe, and shrub alpine vegetation types with high-altitude boundaries of 2400 m, 2800 m, and 2600 m, respectively, with delayed and earlier SOG and EOG below and above each boundary, respectively; and (3) spatial variations in relationships between vegetation phenology changes and climatic factors, where SOG negatively and EOG positively correlated with temperature and precipitation. The mean temperature in the 30 days before SOG and mean total precipitation in the 30 days before EOG were significantly correlated with SOG and EOG timing both negatively and positively, respectively. These results provide guidance for the monitoring of the alpine vegetation phenology on the QTP.

Since the outbreak of coronavirus disease 2019 (COVID-19), the epidemic has been spreading around the world for more than 2 years. Rapid, safe, and on-site detection methods of COVID-19 are in urgent demand for the control of the epidemic. Here, we established an integrated system, which incorporates a machine-learning-based Fourier transform infrared spectroscopy technique for rapid COVID-19 screening and air-plasma-based disinfection modules to prevent potential secondary infections. A partial least-squares discrimination analysis and a convolutional neural network model were built using the collected infrared spectral dataset containing 857 training serum samples. Furthermore, the sensitivity, specificity, and prediction accuracy could all reach over 94% from the results of the field test regarding 968 blind testing samples. Additionally, the disinfection modules achieved an inactivation efficiency of 99.9% for surface and airborne tested bacteria. The proposed system is conducive and promising for point-of-care and on-site COVID-19 screening in the mass population.

Long noncoding RNAs (lncRNAs) have been reported to exert important roles in tumors, including clear cell renal cell carcinoma (ccRCC). PVT1 is an important oncogenic lncRNA which has critical effects on onset and development of various cancers, however, the underlying mechanism of PVT1 functioning in ccRCC remains largely unknown. VHL deficiency-induced HIF2α accumulation is one of the major factors for ccRCC. Here, we identified the potential molecular mechanism of PVT1 in promoting ccRCC development by stabilizing HIF2α. PVT1 was significantly upregulated in ccRCC tissues and high PVT1 expression was associated with poor prognosis of ccRCC patients. Both gain-of-function and loss-of function experiments revealed that PVT1 enhanced ccRCC cells proliferation, migration, and invasion and induced tumor angiogenesis in vitro and in vivo. Mechanistically, PVT1 interacted with HIF2α protein and enhanced its stability by protecting it from ubiquitination-dependent degradation, thereby exerting its biological significance. Meanwhile, HIF2α bound to the enhancer of PVT1 to transactivate its expression. Furthermore, HIF2α specific inhibitor could repress PVT1 expression and its oncogenic functions. Therefore, our study demonstrates that the PVT1/ HIF2α positive feedback loop involves in tumorigenesis and progression of ccRCC, which may be exploited for anticancer therapy.

As a kind of renewable energy, the development and utilization of solar energy is valued by many countries. To accurately provide a basis for the use of solar energy in mainland China, the optimized empirical model is adopted to analyze the variation trends and spatial patterns in solar radiation (SR) during 1961–2016 based on the data of 31 SR sites and 500 sunshine duration (SD) stations. The results indicate that there are obvious discrepancies in the variation trends of annual SR and SD during 1961–2016, with trend conversion occurring in 1992 (SR) and 1980 (SD), respectively. Overall, annual SR decreases at the rate of -3.68 MJ/m²·a in China. Notably, SR declines at the rate of -16.95 MJ/m²·a during 1961–1989 (“dimming” stage), while it increases at the rate of 5.34 MJ/m²·a for 1990–2016 (“brightening” period). In addition, all seasons show a tendency of dimming first and then brightening except for autumn. Compared with SD, SR is more sensitive to changes in pollution, leading to a marked recovery with the reduction of pollution after the 1990s. This study provides a new perspective for the trend difference between SR and SD after the 1990s.

Objectives: This study examines the physical environment in the outpatient waiting area and its effects on overall satisfaction, experience, perceived waiting time, and behavior. Background: Waiting can be a frustrating experience for patients. Previous studies on waiting areas in hospitals have been rooted mainly in the Western cultural context, and research focusing on the impact of the physical environment on the waiting experience with the denser patient concentration in China is important. Methods: Physical environment measurements, observations, and questionnaire surveys were employed. Results: The actual lighting intensity and sound level did not meet the national standards. Sound level and satisfaction with the size of the waiting area, signage system, and visual art on the wall were significant predictors ( R 2 = .463, p = .000) for overall satisfaction. Experiences related to the size of the waiting area, seating, signage system, and restrooms were significant predictors ( R 2 = .373, p = .000) of overall waiting experience. The experience related to the acoustic environment (β = −.184, p = .006) had a significant relationship with perceived waiting time. The increase in participants’ behaviors of looking out of a window and the decrease in looking at other people, looking around, dozing, and looking at a wall might result from a substantial increase in lighting and the availability of a nature view from the window. Conclusions: The effect of the physical setting of waiting areas may positively impact patient satisfaction, waiting experience, perceived waiting time, and behavior, which has implications for patient-centered design.

Cu(I)-based cyclic trinuclear complexes (CTCs) represent one of the most intensively investigated candidates in coinage metal-derived CTCs because of their rich photoluminescence properties. Beyond the molecular level, coordination polymers built upon Cu(I)-based CTCs have developed rapidly in recent times. However, most of the secondary building units (SBUs) on pyrazolyl moieties reported to-date have been centralized on pyrazoles, pyridines and carboxylates and most of the nodes for bridging linkers have been based on copper-halide clusters. This work presents the use of a thioether-functionalized pyrazole to construct Cu(I)-based CTC, 1, which was allowed to react with CuI and BiBr3 for constructing coordination polymers, 2 and 3, respectively. Successful isolation of 2 and 3 highlights that the thioether pendant on the pyrazole can act as a novel class of SBUs on Cu(I)-based CTCs to assemble coordination polymers with a soft Lewis acid and not limited to copper-halide clusters.

With the miniaturization of silicon-based electronic components, power consumption is becoming a fundamental issue for micro-nano electronic circuits. The main reason for this is that the scaling of the supply voltage in the ultra-large-scale integrated circuit cannot keep up with the shrinking of the characteristic size of conventional transistors due to the physical limit termed "Boltzmann Tyranny", in which a gate voltage of at least 60 mV is required to modulate the drain current by one order of magnitude. Accordingly, to solve this problem, several new transistor architectures have been designed to reduce the subthreshold swing (SS) to lower than the fundamental limitation, thus lowering the supply voltage and reducing the power consumption. In this review, we first analytically formulate the SS, summarize the methods for reducing the SS, and propose four new transistor concepts, including tunnelling field-effect transistor, negative capacitance field-effect transistor, impact ionization field-effect transistor, and cold source field-effect transistor. Then, we review their physical mechanisms and optimization methods and consider the potential and drawbacks of these four new transistors. Finally, we discuss the challenges encountered in the investigation of these steep-slope transistors and present the future outlook.

Resistive random access memory (RRAM) based on hybrid organic–inorganic halide perovskite (HOIP) materials has recently gained significant interest due to its low activation energy of ion migration. HOIP RRAM has been reported to exhibit outstanding performance, but they still suffer from issues of high operating voltage and poor uniformity. Here, we provide an efficient method for improving the resistive switching characteristics of HOIP RRAM by integrating an Au tip in the bottom electrode to regulate the growth of conductive filaments (CFs). The Ag/polymethylmethacrylate/CH3NH3PbI3/Au tip/indium tin oxide RRAM exhibits a lower set voltage of −0.11 V, a larger ON/OFF ratio of 108, excellent durability (up to 4 × 103 times), low power consumption, and good non-volatility. Moreover, the time-dependent resistive switching characteristics were investigated by a statistical analysis of the data on the turn-on time based on the Weibull distribution. Tests using transmission electron microscopy, electron energy depletion spectroscopy, and energy dispersive spectroscopy have demonstrated that the formation and rupture of CFs occur mainly in the CH3NH3PbI3 layer and that the CFs should be composed of Ag atoms and I vacancies. Our research offers a strategy for enhancing the stability of perovskite devices and promoting the application of low-power, high-density non-volatile memory devices.

The strong, stable radical signal is forged from two levels of structural design. On the molecular level, we fused terephthalic acid with two 1,4-dithiin (-S-CH = CH-S-) units to afford a polycyclic (3-ring), sulfur-rich linker (TTA) with versatile reactivity—e.g., for generating stable radicals. On the solid-state level, the linker was crystallized with Eu(III) to form EuTTA as a 3D metal-organic framework (MOF) featuring stacks of TTA molecules along the Eu-carboxyl rod domain. As revealed by single-crystal X-ray diffraction, the slightly loosened packing of the TTA molecules allows wiggle room for uniquely selective thermal reactions: among the repeat of three TTA molecules along the stack, one first transforms into benzodithiophene (by extruding one S atom from each of the dithiin wings) at 230°C, while the other two TTA molecules only react at higher temperatures (e.g., 300–350°C)—to form bis(dithiole) and other sulfur-stabilized radicals, as well as covalent crosslinks thereof. Aside from the highest thermal stability observed of its radicals (above 300°C), the black MOF product (i.e., EuTTA-350; obtained from heating at 350°C) remain crystalline, and water/air-stable, and features strong broad absorption in the visible and near IR region. As a result, EuTTA-350 achieves highest efficiencies in both photothermal conversion and solar-driven water evaporation among MOF materials, holding promise in solar steam generation.

Objective To identify novel biomarkers and therapeutic targets for primary melanoma using network-based microarray data analysis. Methods Eligible microarray datasets from the Gene Expression Omnibus (GEO) database were used to identify differentially expressed genes (DEGs). The protein-protein interaction (PPI) network, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to identify hub genes and pathways that might affect the survival of melanoma patients. Immunohistochemistry results obtained from the Human Protein Atlas (HPA) database confirmed the protein expression levels of hub genes. The Cancer Genome Atlas (TCGA) database was used to further verify the gene expression levels and conduct survival analysis. Results Three microarray datasets (GSE3189, GSE15605, and GSE46517) containing 122 melanoma and 30 normal skin tissue samples were included. A total of 262 common differentially expressed genes (cDEGs) were identified based on three statistical approaches (Fisher's method, the random effects model (REM), and vote counting) with strict criteria. Of these, two upregulated genes, centromere protein F (CENPF) and pituitary tumor-transforming gene 1 (PTTG1), were selected as hub genes. HPA and TCGA database analyses confirmed that CENPF and PTTG1 were overexpressed in melanoma. Survival analysis showed that high expression levels of CENPF were significantly correlated with decreased overall survival (OS) (P=0.028). Conclusion The expression level of CENPF was significantly upregulated in melanoma and correlated with decreased OS. Thus, CENPF may represent a novel biomarker and therapeutic target for melanoma patients.

Functionalized polypeptides have attracted tremendous interest in recent years and found many stimulating applications owing to their tunable physicochemical characteristics including hydrophilicity and stimuli-responsive behavior. The development of new strategies to produce these polymers without metallic contaminants is crucial for their applications in high-value and sensitive domains, such as biomedical, microelectronic, food-packaging, and personal beauty care fields. Herein, a highly efficient strategy to access well-defined site-specific functionalized polypeptides is developed by combining Michael reaction with hydrogen-bonding organocatalytic ROP of NCA. A library of chain-end and chain-middle functionalized polypeptides (14 examples) with predesigned molecular weights and low polydispersities are readily prepared with this approach. Specifically, the whole synthetic process is metal-free, fulfilling high activity and selectivity at room temperature.

Organic luminogens have extensive applications due to their unique photophysical properties. In recent years, nonconjugated organic luminogens, in contrast to traditional conjugated luminogens, have gained much attention because of their facile preparation, environmental friendliness, and biocompatibility. In this study, a new kind of nonconventional luminogen based on dynamic covalent cross-linked polyhydroxyurethane is reported for the first time. The new luminogen not only exhibits intrinsic strong fluorescent emission in the solid state but also possesses high mechanical properties along with good shape memory and self-healing properties. In addition, the new luminogens are synthesized from aliphatic polyfunctional cyclic carbonate and amines via a much more straightforward method, avoiding the use of toxic isocyanates. Investigations indicated that the intrinsic luminescence of the resultant luminogens was induced by the cross-linking of polymer chains and could be well tuned by controlling the degree of cross-linking. By taking advantage of the unique characteristics of the resultant polymer luminogens, we further developed a facile method, named "light-mediated ink-free screen printing", for anticounterfeiting paper fabrication. Different from traditional ink-based printing technology, the new method used UV-light instead of expensive security ink to encode anticounterfeiting information on natural cellulose paper. The anticounterfeiting information is stable under various wet conditions, showing promising applications in the fast-growing counterfeiting of pharmaceuticals, packaging, and the food industry.

The ecological security pattern is an important way to coordinate the contradiction between regional economic development and ecological protection and is conducive to promoting regional sustainable development. This study examines Guangxi, a karst region in China. The ecosystem service function and ecological environment sensitivity were both selected to evaluate the ecological conservation importance, and based on the results of the ecological conservation importance evaluation, suitable patches were selected as ecological sources. Meanwhile, resistance factors were selected from both natural factors and human activities to construct a comprehensive resistance surface, circuit theory was used to identify ecological corridors, ecological pinch points, and ecological barrier points, and ecological protection suggestions were then proposed. The results show that there are 50 patches of ecological sources in Guangxi, with a total area of 60,556.99 km2; 115 ecological corridors, with the longest corridor reaching 194.97 km; 301 ecological pinch points, whose spatial distribution is fragmented; and 286 ecological barrier points, most of which are concentrated in the central part of Guangxi. The results of this study provide a reference for the construction of ecological security patterns and ecological conservation in developing countries and karst areas.