Regulation of Ionic Bond in GroupⅡB Transition Metal Iodides

Using a swarm intelligence structure search method combining with first-principles calculations,three new structures of Zn-I and Hg-I compounds are discovered and pressure-composition phase diagrams are determined.An interesting phenomenon is found,that is,the compounds that are stable at 0 GPa in both systems will decompose into their constituent elements under certain pressure,which is contrary to the general intuition that pressure always makes materials more stability and density.A detailed analysis of the decomposition mechanism reveals the increase of formation enthalpy with the increase of pressure due to contributions from bothΔU andΔ[P V].Pressure-dependent studies of theΔV demonstrate that denser materials tend to be stabilized at higher pressures.Additionally,charge transfer calculations show that external pressure is more effective in regulating the ionic bond of Hg-I,resulting in a lower decomposition pressure for HgI_(2)than for ZnI_(2).These findings have important implications for designs and syntheses of new materials,as they challenge the conventional understanding on how pressure affects stability.

A new transition metal diphosphideα-MoP_(2) synthesized by a high-temperature and high-pressure technique

Monoclinicα-MoP_(2),with the OsGe2-type structure(space group C2/m,Z=4)and lattice parameters a=8.7248(11)Å,b=3.2322(4)Å,c=7.4724(9)Å,andβ=119.263°,was synthesized under a pressure of 4~GPa at a temperature between 1100℃and 1200℃.The structure ofα-MoP_(2) and its relationship to other transition metal diphosphides are discussed.Surprisingly,the ambient pressure phase orthorhombicβ-MoP_(2)(space group Cmc21)is denser in structure thanα-MoP_(2).Room-temperature high-pressure x-ray diffraction studies exclude the possibility of phase transition fromβ-MoP_(2) to α-MoP_(2),suggesting thatα-MoP_(2) is a stable phase at ambient conditions;this is also supported by the total energy and phonon calculations.

Comparative metabolomics analysis in the clean label ingredient of NFC spine grape juice processed by mild heating vs high pressure processing

Not from concentrate(NFC)fruit juice is the crucial clean label ingredient for new-style tea-making due to its pleasant color and fresh aroma.Here,we compared the effects of mild heating(MH)and high pressure processing(HPP)on physicochemical characters and phytochemicals in NFC spine grape juice based on metabolomics analysis.Similar compound profiles were observed between HPP-treated and fresh juices.The richer phytochemical compounds comprised malvidin-3-O-glucoside,malvidin-3,5-di-O-glucoside,quercetin-3-O-rhamnoside,quercetin-3-Oglucuronide,catechin,caffeic acid,ferulic acid,procyanidin B1,procyanidin B2 were obtained after MH treatment.Nine marker phenolics and two marker tripeptides(i.e.,Glu-Val-Phe and Leu-Leu-Tyr)were identified to differentiate MH from HPP treatment,of which higher contents occurred in the MH group.Storage time experiments showed that the Glu-Val-Phe could serve as potential markers for monitoring storage of spine grape juice.These results provide new insights into the effects of processing on individual phytochemical changes and the guide for commercial application of production of spine grape NFC juice.

Near‑Instantaneously Self‑Healing Coating toward Stable and Durable Electromagnetic Interference Shielding

Durable electromagnetic interference(EMI)shielding is highly desired,as electromagnetic pollution is a great concern for electronics’stable performance and human health.Although a superhydrophobic surface can extend the service lifespan of EMI shielding materials,degradation of its protection capability and insufficient self-healing are troublesome issues due to unavoidable physical/chemical damages under long-term application conditions.Here,we report,for the first time,an instantaneously self-healing approach via microwave heating to achieve durable shielding performance.First,a hydrophobic 1H,1H,2H,2H-perfluorooctyltriethoxysilane(POTS)layer was coated on a polypyrrole(PPy)-modified fabric(PPy@POTS),enabling protection against the invasion of water,salt solution,and corrosive acidic and basic solutions.Moreover,after being damaged,the POTS layer can,for the first time,be instantaneously self-healed via microwave heating for a very short time,i.e.,4 s,benefiting from the intense thermal energy generated by PPy under electromagnetic wave radiation.This self-healing ability is also repeatable even after intentionally severe plasma etching,which highlights the great potential to achieve robust and durable EMI shielding applications.Significantly,this approach can be extended to other EMI shielding materials where heat is a triggering stimulus for healing thin protection layers.We envision that this work could provide insights into fabricating EMI shielding materials with durable performance for portable and wearable devices,as well as for human health care.

A Study of Transcranial magnetic stimulation For Extinction about Early Traumatic Memory Description

Individuals will experience strong traumatic memories after traumatic events such as earthquakes,car accidents,or loss of loved ones,the most common of which is fear memory.In this experiment,a multisensory compound stimulation model(electric stimulation+picture)was used as the conditional stimulus,and the skin electrical response was used as the index of fear response.The effect of retrievalextinction paradigm on the conditional fear extinction was tested.In addition,high-frequency rTMS was introduced as a treatment.To explore the therapeutic effect of TMS on conditional fear,with the aim of providing new measures for the treatment of PTSD.

Programmable photonic RF filters based on an integrated Fabry-Pérot laser with a saturable absorber

We propose and experimentally demonstrate the programmable photonic radio frequency(RF)filters based on an integrated Fabry-Pérot laser with a saturable absorber(FP-SA).Owing to the high output power and the relative flatness spectrum of the FP-SA laser,only a waveshaper and an erbium-doped fiber amplifier(EDFA)were needed,which can greatly reduce the complexity of the system.The sinc filter employed 87 taps,representing a record-high tap number and resulting in a 3-d B bandwidth of 0.27 GHz and a quality factor of 148.Furthermore,Gaussian apodization enabled the out-of-band rejection of the filter to reach 34 d B and the center frequency to be finely tuned over a wide range,spanning from 4 to 14 GHz.These results indicate that the proposed scheme could provide a promising guideline for the photonic RF filters that demand both high reconfigurability and greatly reduced size and complexity.

Experimental demonstration of coherent photonic neural computing based on a Fabry–Perot laser with a saturable absorber

As Moore’s law has reached its limits,it is becoming increasingly difficult for traditional computing architectures to meet the demands of continued growth in computing power.Photonic neural computing has become a promising approach to overcome the von Neuman bottleneck.However,while photonic neural networks are good at linear computing,it is difficult to achieve nonlinear computing.Here,we propose and experimentally demonstrate a coherent photonic spiking neural network consisting of Mach–Zehnder modulators(MZMs)as the synapse and an integrated quantum-well Fabry–Perot laser with a saturable absorber(FP-SA)as the photonic spiking neuron.Both linear computation and nonlinear computation are realized in the experiment.In such a coherent architecture,two presynaptic signals are modulated and weighted with two intensity modulation MZMs through the same optical carrier.The nonlinear neuron-like dynamics including temporal integration,threshold,and refractory period are successfully demonstrated.Besides,the effects of frequency detuning on the nonlinear neuron-like dynamics are also explored,and the frequency detuning condition is revealed.The proposed hardware architecture plays a foundational role in constructing a large-scale coherent photonic spiking neural network.

Electrospinning Technique Meets Solar Energy: Electrospun Nanofiber‑Based Evaporation Systems for Solar Steam Generation

The huge gap between inadequate clean water supply and demanding human needs can be narrowed by sustainable and green methods of solar-driven evaporation,which effectively converts solar energy into thermal energy to purify seawater and wastewater.Electrospun materials produced from a facile electrospinning technique can be combined with functional photothermal materials,giving rise to various superior advantages in solar water evaporation.However,to date,few reviews have focused on this topic.This article reviews the recent progress of electrospun nanofiber-based evaporation systems focusing on polymer selection,available solar materials,incorporation strategies of solar materials,system configurations,factors influencing the performance,and applications of electrospun nanofiber evaporation systems.The incorporation strategies of solar materials and system configurations in electrospun nanofiber evaporators are classified and systematically discussed.Finally,the challenges and perspectives of the electrospun nanofiber evaporation systems are also presented.This review updates the progress of electrospun nanofiber evaporation systems and simultaneously stimulates attractive research on designing electrospun nanofiber-based photothermal systems for applications in solar water evaporation,photothermal therapy,electricity generation,and other related areas.

Transcriptome Profiling Reveals Auxin and Cytokinin Regulating Somatic Embryogenesis in Different Sister Lines of Cotton Cultivar CCRI24

To get a broader view on the molecular mechanisms underlying somatic embryogenesis （SE） in cotton （Gossypium hirsutum L.）, global analysis of cotton transcriptome dynamics during SE in different sister lines was performed using RNA-Seq. A total of 204 349 unigenes were detected by de novo assembly of the 214 977 462 Illumina reads. The quantitative reverse transcription-polymerase chain reaction （qRT-PCR） measurements were positively correlated with the RNA-Seq results for almost all the tested genes （R2 -- 0.841, correlation was significant at the 0.01 level）. Different phytohormone （auxin and cytokinin） concentration ratios in medium and the endogenous content changes of these two phytohormones at two stages in different sister lines suggested the roles of auxin and cytokinin during cotton SE. On the basis of global gene regulation of phytohormone-related genes, numerous genes from all the differentially expressed transcripts were involved in auxin and cytokinin biosynthesis and signal transduction pathways. Analyses of differentially expressed genes that were involved in these pathways revealed the substantial changes in gene type and abundance between two sister lines. Isolation, cloning and silencing/ overexpressing the genes that revealed remarkable up- or down-expression during cotton SE were important. Furthermore, auxin and cytokinin play a primary role in SE, but potential cross-talk with each other or other factors remains unclear.

Prediction of VIGS efficiency by the Sfold program and its reliability analysis in Gossypium hirsutum

Genetic transformation in some plant species, including cotton （Gossypium hirsutum）, is hampered by laborious and time-consuming processes and often unachievable. Virus-induced gene silencing （VIGS） by double-stranded RNAs can serve as a reverse-genetics tool to determine gene function. However, knockdown levels vary greatly when using a tobacco rattle virus-based vector that carries different cDNA fragments of a gene. How to choose the optional target fragment for high interference efficiency is very challenging. Addressing this challenge requires increasing the efficacy of small interference RNA （siRNA） in target fragment. Here, we describe a method to assess VIGS efficiency by comparing the following parameters of siRNA in target sequence： the disruptionenergy of the target （△Gdisruption）, the differential stability of siRNA duplex ends （DSSE）, and the internal stability at positions 9-14 of the siRNA antisense strand （AIS）, which are calculated by Sfold program （http：//sfold.wadsworth. org）. We find that the siRNAs with low mGdisruption, high DSSE and high AIS have high activity and easily result in high VIGS efficiency by experimentally testing the actual knockdown levels of the four target genes, GhPDS, GhCLA1, GhAOS1, and GhCXE1 via choosing different target sequences for each gene. Therefore, the Sfold pro- gram can be used to analyze target sequences when car- rying out VIGS design to increase gene-silencing effects in plants.

High-efficiency and broadband four-wave mixing in a silicon-graphene strip waveguide with a windowed silica top layer

We experimentally demonstrate high-efficiency and broadband four-wave mixing in a silicon-graphene strip waveguide. A four-wave mixing conversion efficiency of -38.7 d B and a 3-dB conversion bandwidth of 35 nm are achieved in the silicon-graphene strip waveguide with an optimized light-graphene interaction length of 60 μm. The interaction length is controlled by a windowed area of silica layer on the silicon waveguide.Numerical simulations and experimental studies are carried out and show a nonlinear parameter γGOSas large as 10~4 W^(-1)· m^(-1).

中国环境治理:国家和非国家行为体的互动

在西方国家,由于政府解决环境问题的能力有限,催生了各种作为政府行政补充或提供解决环境问题替代机制的"非国家行为体"的崛起。类似的,中国的治理过程也模糊了国家和其他主体之间的区别,"国家的影子"是影响解决环境问题行动的重要因素。在西方体系中的非国家行为体对应到中国是事业单位、社会团体和电子平台,这些组织都和国家紧密相关。同时,国际非政府组织和跨国公司也是重要参与者。因此,在中国起作用的影响机制很大程度上不同于西方经验中所熟悉的机制。鉴于中国经济增长和新兴贸易关系网络的重要性,这一结论对寻求全球环境问题的解决具有深远影响。

Polarity-activated super-resolution imaging probe for the formation and morphology of amyloid fibrils

The formation of amyloid plaques usually occurs in the early-stage of Alzheimer’s disease(AD).Stimulated emission depletion(STED)imaging provided a powerful tool for visualizing amyloid structures on the nanometer scale.However,many commercial probes adopted in detecting amyloid fibrils are inapplicable to STED imaging,owing to their unmatched absorption and emission wavelengths,small Stokes'shift,easy photo-bleaching,etc.Herein,we demonstrated a polarity-activated STED probe based on an intramolecular charge transfer donor(D)-7c-acceptor(A)compound.The electron-rich carbazole group and the electron-poor pyridinium bromide group,linked by 7i-conjugated thiophen-bridge,ensure strong near infrared(NIR)emission with a Stokes'shift larger than 200 nm.The tiny change in polarity before and after binding with amyloid plaques leads to a transition from weakly emission charge-transfer(CT)state(Φ<0.04)to highly emissive locally-excited(LE)state(Φ=0.57),giving rise to a fluorescence Turn-On probe.Together with large Stokes'shift,good photostability and high depletion efficiency,the super-resolution imaging of the formation and morphology of amyloid fibrils in vitro based on this probe was realized with a lateral spatial resolution better than 33 nm at an extremely low depletion power.Moreover,the ex-vivo super-resolution imaging of(E)-1-butyl-4(2-(5-(9-ethyl-9Hcarbazol-3-yl)thiophen-2-yl)vinyl)pyridinium bromide(CTPB)probe in Aβ plaques in the brain slices of a Tg mouse was demonstrated.This research provides a demonstration of the super resolution imaging probe of amyloid fibrils based on polarity-response mechanism,providing a new approach to the development of future amyloid probes.

Genome sequence of Gossypium anomalum facilitates interspecific introgression breeding

Crop wild relatives are an important reservoir of natural biodiversity. However, incorporating wild geneticdiversity into breeding programs is often hampered by reproductive barriers and a lack of accurate genomicinformation. We assembled a high-quality, accurately centromere-anchored genome of Gossypium anomalum, a stress-tolerant wild cotton species. We provided a strategy to discover and transfer agronomicallyvaluable genes from wild diploid species to tetraploid cotton cultivars. With a (Gossypium hirsutum 3 G.anomalum)2 hexaploid as a bridge parent, we developed a set of 74 diploid chromosome segment substitution lines (CSSLs) of the wild cotton species G. anomalum in the G. hirsutum background. This set of CSSLsincluded 70 homozygous substitutions and four heterozygous substitutions, and it collectively containedabout 72.22% of the G. anomalum genome. Twenty-four quantitative trait loci associated with plant height,yield, and fiber qualities were detected on 15 substitution segments. Integrating the reference genome withagronomic trait evaluation of the CSSLs enabled location and cloning of two G. anomalum genes thatencode peroxiredoxin and putative callose synthase 8, respectively, conferring drought tolerance andimproving fiber strength. We have demonstrated the power of a high-quality wild-species reference genomefor identifying agronomically valuable alleles to facilitate interspecific introgression breeding in crops.

A news picture geo-localization pipeline based on deep learning and street view images

Numerous news or event pictures are taken and shared on the internet every day that have abundant information worth being mined,but only a small fraction of them are geotagged.The visual content of the news image hints at clues of the geographical location because they are usually taken at the site of the incident,which provides a prerequisite for geo-localization.This paper proposes an automated pipeline based on deep learning for the geo-localization of news pictures in a large-scale urban environment using geotagged street view images as a reference dataset.The approach obtains location information by constructing an attention-based feature extraction network.Then,the image features are aggregated,and the candidate street view image results are retrieved by the selective matching kernel function.Finally,the coordinates of the news images are estimated by the kernel density prediction method.The pipeline is tested in the news pictures in Hong Kong.In the comparison experiments,the proposed pipeline shows stable performance and generalizability in the large-scale urban environment.In addition,the performance analysis of components in the pipeline shows the ability to recognize localization features of partial areas in pictures and the effectiveness of the proposed solution in news picture geo-localization.

无气管内插管麻醉电视胸腔镜辅助肺切除术后患者快速康复的临床疗效观察

目的评价无气管内插管麻醉电视胸腔镜手术(VATS)肺切除术后患者快速康复的临床疗效。方法回顾性队列研究。纳入2018年9月—2020年12月云南省第一人民医院胸外科行肺切除术患者228例,其中男118例、女110例,年龄30~76岁。根据麻醉方式不同分为无插管组(119例)和插管组(109例)。对比观察两组患者的基线资料、手术时间、术中出血量和手术相关并发症情况,以及术后快速康复相关指标,包括术后恢复经口饮食时间、通气时间、下床活动和住院时间、术后胸腔引流量及术后24 h疼痛视觉模拟评分法(VAS)评分等。结果两组患者年龄、性别、体质量指数(BMI)、病变类型和基础病史等基线资料比较,差异均无统计学意义(P值均>0.05)。无插管组患者手术时间[120.0(60.0,150.0)min]、术中出血量[40.0(20.0,50.0)mL]、术后VAS评分[3.0(3.0,4.0)分]、术后胸腔引流量[300.0(150.0,545.0)mL]均低于插管组[130.0(90.0,175.0)min、50.0(20.0,100.0)mL、4.0(4.0,4.0)分、510.0(90.0,777.5)mL],术后恢复经口进食时间[1.5(1.0,2.0)h]、下床活动时间[2.0(2,2.5)h]和通气时间[1.0(1.0,1.0)d]早于插管组[4.5(4.0,5.0)h、12.0(10.0,12.0)h和1.0(1.0,1.0)d],差异均有统计学意义(Z=-2.229、-3.278、-8.000、-4.019、-13.310、-13.076和-3.297,P值均<0.05)。两组患者住院时间、术后住院期间及出院后30 d内并发症发生率比较,差异无统计学意义(Z=-0.178,χ^(2)=2.127、3.648,P值均>0.05)。结论与插管麻醉相比,无气管内插管麻醉VATS肺切除术后患者早期快速康复的临床效果更好,值得临床外科推广。

MCA-TFP Model:A Short-Term Traffic Flow Prediction Model Based on Multi-characteristic Analysis

With the urbanization,urban transportation has become a key factor restricting the development of a city.In a big city,it is important to improve the efficiency of urban transportation.The key to realize short-term traffic flow prediction is to learn its complex spatial correlation,temporal correlation and randomness of traffic flow.In this paper,the convolution neural network(CNN)is proposed to deal with spatial correlation among different regions,considering that the large urban areas leads to a relatively deep Network layer.First three gated recurrent unit(GRU)were used to deal with recent time dependence,daily period dependence and weekly period dependence.Considering that each historical period data to forecast the influence degree of the time period is different,three attention mechanism was taken into GRU.Second,a twolayer full connection network was applied to deal with the randomness of short-term flow combined with additional information such as weather data.Besides,the prediction model was established by combining these three modules.Furthermore,in order to verify the influence of spatial correlation on prediction model,an urban functional area identification model was introduced to identify different functional regions.Finally,the proposed model was validated based on the history of New York City taxi order data and reptiles for weather data.The experimental results show that the prediction precision of our model is obviously superior to the mainstream of the existing prediction methods.