红光诱导菠菜叶提取物催化对羟基苯甲腈的绿色合成——药学类本科生新创实验的研究与探索

在现代有机化学合成反应中,光照是一种重要的反应条件,但是在现行的有机化学实验教材中很少涉及。本新创实验采用微量化方法,借鉴自然界中的光合作用原理,尝试利用可见光红光诱导菠菜叶中的叶绿素,催化对氰基苯硼酸与空气中的氧气发生氧化反应合成对羟基苯甲腈。在我校有机化学实验教学中引入该综合实验,具有如下优点:(1)所用催化剂绿色环保、简单易得,合成过程安全可靠,实验成本低;(2)微量化实验有利于减少环境污染,提高实验安全,节省试剂和时间,减少仪器损耗,有利于培养学生严谨细致的实验作风和习惯;(3)在拓宽学生的知识面和眼界的同时,激发学生的学习兴趣,调动学生的学习积极性。

Ultrahigh performance passive radiative cooling by hybrid polar dielectric metasurface thermal emitters

Real-world passive radiative cooling requires highly emissive,selective,and omnidirectional thermal emitters to maintain the radiative cooler at a certain temperature below the ambient temperature while maximizing the net cooling power.Despite various selective thermal emitters have been demonstrated,it is still challenging to achieve these conditions sim-ultaneously because of the extreme difficulty in controlling thermal emission of photonic structures in multidimension.Here we demonstrated hybrid polar dielectric metasurface thermal emitters with machine learning inverse design,en-abling a high emissivity of~0.92 within the atmospheric transparency window 8-13μm,a large spectral selectivity of~1.8 and a wide emission angle up to 80 degrees,simultaneously.This selective and omnidirectional thermal emitter has led to a new record of temperature reduction as large as~15.4°C under strong solar irradiation of~800 W/m2,signific-antly surpassing the state-of-the-art results.The designed structures also show great potential in tackling the urban heat island effect,with modelling results suggesting a large energy saving and deployment area reduction.This research will make significant impact on passive radiative cooling,thermal energy photonics and tackling global climate change.

Debt,sleep deprivation and psychological distress among online ride-hailing drivers:evidence from China

An online ride-hailing driver(ORHD)refers to a driver who takes orders and provides rental car services to passengers via an online service platform.1 ORHD plays a significant role in the urban transport system worldwide,operating through many platforms.According to official data from the Chinese Ministry of Transport,a total of 1.6 million vehicle transport permits were issued by the end of March 2022.

Double-tract reconstruction is superior to esophagogastrostomy in controlling reflux esophagitis and enhancing quality of life after proximal gastrectomy:Results from a prospective randomized controlled clinical trial in China

Objective:The aim of this study was to prospectively compare double-tract reconstruction(DTR)and esophagogastrostomy(EG)after proximal gastrectomy(PG)regarding the incidence of reflux esophagitis,quality of life(QOL),nutritional status and surgical safety.Methods:This study was a randomized controlled trial.Patients eligible for PG were enrolled and randomly assigned to the EG group and DTR group.The characteristics of patients,parameters for surgical safety,incidence of reflux esophagitis,nutrition status and QOL were collected and compared between the two groups.Univariate analysis and multivariate analysis were performed to determine the significant factors affecting the incidence of reflux esophagitis after PG.Results:Thirty-seven patients of the EG group and 36 patients of the DTR group were enrolled.The incidence of reflux esophagitis was significantly lower in the DTR group than in the EG group(8.3%vs.32.4%,P=0.019).The DTR group demonstrated a more favorable QOL than the EG group after PG.The nutritional status was balanced within the EG group and the DTR group.The operation time was longer in the DTR group than in the EG group(191 min vs.221 min,P=0.001),while surgical safety was similar in the two groups.Conclusions:Our research demonstrated that DTR is superior to EG after PG in terms of the incidence of reflux esophagitis and provides a more satisfactory QOL without increasing surgical complications or sacrificing nutritional status.

常用肿瘤基因分析方法及基于TCGA数据库的分析应用

随着二代测序技术的快速发展,数据量不断累积,肿瘤学家的目光逐渐由多物种测序转移至高通量测序数据的分析和比对。基因数据分析方法层出不穷,高通量的组学分析手段不断优化和创新,基因数据的挖掘和分析工作正处于飞速发展的时期。以肿瘤病人样本为核心的数据库The Cancer Genome Atlas (TCGA)由此应运而生,该数据库全方位记录了从临床肿瘤病人样本得到的基因数据如DNA序列、转录本信息、表观遗传学修饰等。本文主要从数据分析方法、TCGA数据库及其应用实例等3个方面详细介绍了肿瘤相关基因数据的深入挖掘和生物信息学分析方法的最新研究进展,以期为研究人员利用大数据发现肿瘤防治相关的新靶点提供借鉴和参考。

Construction and external validation of a nomogram that predicts lymph node metastasis in early gastric cancer patients using preoperative parameters

Objective: To create a nomogram to predict the incidence of lymph node metastasis(LNM) in early gastric cancer(EGC) patients and to externally validate the nomogram.Methods: To construct the nomogram,we retrospectively analyzed a primary cohort of 272 EGC patients.Univariate analysis and a binary logistic regression were performed.A nomogram predicting the incidence of LNM in EGC patients was created.The discrimination ability of the nomogram was measured using the concordance index(c-index),and the nomogram was also calibrated.Then,another prospective cohort of 81 patients was analyzed to validate the nomogram.Results: In the primary cohort,LNM was pathologically confirmed in 37(13.6%) patients.In multivariate analysis,the presence of an ulcer,the maximum lesion diameter observed via gastroscopy,the thickness of the lesion observed via endoscopic ultrasonography,and the presence of enlarged lymph nodes on computed tomography(CT) were independent risk factors for LNM.A nomogram was then created based on the regression model with the c-index of 0.905,and the calibration curve of the nomogram fell approximately on the ideal 45-degree line.The cut-off score of the nomogram was 110,and the sensitivity,specificity,positive predictive and negative predictive values of the nomogram in the primary cohort were 81.1%,86.0%,47.6% and 96.7%,respectively,and in the prospective validation cohort were 75.0%,91.0%,60.0% and 95.5%,respectively.The calibration curve of the external validation cohort was almost on the 45-degree line.Conclusions: We developed an effective nomogram predicting the incidence of LNM for EGC patients.

Band structure engineering in metal halide perovskite nanostructures for optoelectronic applications

Metal halide perovskite nanostructures have emerged as low-dimensional semiconductors of great significance in many fields such as photovoltaics,photonics,and optoelectronics.Extensive efforts on the controlled synthesis of perovskite nanostructures have been made towards potential device applications.The engineering of their band structures holds great promise in the rational tuning of the electronic and optical properties of perovskite nanostructures,which is one of the keys to achieving efficient and multifunctional optoelectronic devices.In this article,we summarize recent advances in band structure engineering of perovskite nanostructures.A survey of bandgap engineering of nanostructured perovskites is firstly presented from the aspects of dimensionality tailoring,compositional substitution,phase segregation and transition,as well as strain and pressure stimuli.The strategies of electronic doping are then reviewed,including defect-induced self-doping,inorganic or organic molecules-based chemical doping,and modification by metal ions or nanostructures.Based on the bandgap engineering and electronic doping,discussions on engineering energy band alignments in perovskite nanostructures are provided for building high-performance perovskite p-n junctions and heterostructures.At last,we provide our perspectives in engineering band structures of perovskite nanostructures towards future low-energy optoelectronics technologies.

Identification of lymph node metastasis by computed tomography in early gastric cancer

Objective:Lymph node status is critical when selecting treatment methods for patients with early gastric cancer(EGC).The aim of this study was to assess the diagnostic value of computed tomography(CT)for detection of lymph node metastasis(LNM)in patients with EGC.Methods:We retrospectively analyzed patients who had pathologically confirmed EGC between November2010 and January 2019.After 1:1 propensity score matching,65 patients with LNM and 65 patients without LNM were retained for comparison.The long diameter(LD)and short diameter(SD)of all visualized lymph nodes in all stations were recorded.The diagnostic value of LNM was assessed with receiver operating characteristic analysis.Results:Among 130 patients,we found a total of 558 lymph nodes on the CT images.Among the diagnostic indicators,the number,sum of LD and sum of SD of lymph nodes greater than 3 mm had better discrimination.The areas under the curve were all greater than 0.75.As for different regions,the optimal cutoff values of number,the sum of LD and sum of SD were determined as follows:overall,≥4,19.9 mm and 13.5 mm;left gastric artery basin,≥3,15.7 mm and 8.6 mm;right gastroepiploic artery basin,≥2,8.6 mm and 7.0 mm.Conclusions:CT is valuable for diagnosing LNM in EGC patients.The number,sum of LD and sum of SD of lymph nodes greater than 3 mm are preferable indicators.Different regional lymph nodes have different optimal criteria for predicting LNM in ECG patients.

A general model for trailing edge serrations simulation on wind turbine airfoils

Trailing edge serrations(TESs)are capable of noticeably suppressing the turbulent trailing edge noise induced by rotating wind turbine blades and become an integral part of a blade.However,the challenges involved in the dimensional design of serration height 2 h,wavelengthλand flap angleϕare yet to be dealt with in a satisfactory manner.To address the problem,a general model for simulating the effects of serrations on the hydrodynamic and aeroacoustic performance is proposed due to its ease of use and relatively low requirements for user input.The solid serrations are replicated by momentum sources calculated by its aerodynamic forces.Then,a case relevant to wind turbine airfoil is examined,a hybrid improved delay detached eddy simulation(IDDES)method coupled with FW-H integration is deployed to obtain the flow features and far-field sound pressure level.It is found that the modeling method could reproduce the flow field and noise as serrated airfoil.

Nomogram for predicting lymph node metastasis rate of submucosal gastric cancer by analyzing clinicopathological characteristics associated with lymph node metastasis

Background： To combine dinicopathological characteristics associated with lymph node metastasis for submucosal gastric cancer into a nomogram. Methods： We retrospectively analyzed 262 patients with submucosal gastric cancer who underwent D2 gastrectomy between 1996 and 2012. The relationship between lymph node metastasis and clinicopathological features was statistically analyzed. With multivariate logistic regression analysis, we made a nomogram to predict the possibility of lymph node metastasis. Receiver operating characteristic （ROC） analysis was also performed to assess the predictive value of the model. Discrimination and calibration were performed using internal validation. Results： A total number of 48 （18.3%） patients with submucosal gastric cancer have pathologically lymph node metastasis. For submucosal gastric carcinoma, lymph node metastasis was associated with age, tumor location, macroscopic type, size, differentiation, histology, the existence of ulcer and lymphovascular invasion in univariate analysis （all P〈0.05）. The multivariate logistic old, macroscopic type III or mixed, undifferentiated type, regression analysis identified that age _〈50 years and presence of lymphovascular invasion were independent risk factors of lymph node metastasis in submucosal gastric cancer （all P〈0.05）. We constructed a predicting nomogram with all these factors for lymph node metastasis in submucosal gastric cancer with good discrimination [area under the curve （AUC） =0.844]. Internal validation demonstrated a good discrimination power that the actual probability corresponds closely with the predicted probability. Conclusions： We developed a nomogram to predict the rate of lymph node metastasis for submucosal gastric cancer. With good discrimination and internal validation, the nomogram improved individualized predictions for assisting clinicians to make appropriated treatment decision for submucosal gastric cancer patients.

Dispersion hydrophobic electrolyte enables lithium-oxygen battery enduring saturated water vapor

Li-O_(2) batteries gain widespread attention as a can didate for next-generati on energy storage devices due to their extraordinary theoretic specific energy.The semi-open structure of Li-O_(2) batteries causes many parasitic reactions,especially related to water.Water is a double-edged sword,which destroys Li anode and simultaneously triggers a solution-based pathway of the discharge product.In this work,hexamethyldisilazane(HMDS)is introduced into the electrolyte of an aprotic Li-O_(2) battery.HMDS has a strong ability to combine with a trace of water to gen erate a hydrophobic hexamethyldisiloxa ne(MM),which eliminates water from the electrolyte decomposition and then prevents the Li anode from producing the insulating LiOH with water.In this case,the hydrophobic MM disperses in the ether-based electrolyte,forming a dispersion hydrophobic electrolyte.This electrolyte can anchor water from the environment on the cathode side,which triggers a solution-based pathway and regulates the growth morphology of the discharge product and consequently increases the discharge capacity.Compared with the Li-O_(2) battery without the HMDS,the HMDS-containing Li-O_(2) battery contributes an about 13-fold increase of cyclability(400 cycles,1800 h)in the extreme environment of saturated water vapor.This work opens a new approach for directly operating aprotic Li-O_(2) batteries in ambient air.

Characteristics of lymph node stations/basins metastasis and construction and validation of a preoperative combination prediction model that accurately excludes lymph node metastasis in early gastric cancer

Objective:To explore the candidate indications for function-preserving curative gastrectomy and sentinel lymph node navigation surgery in early gastric cancer(EGC).Methods:The clinicopathological data of 561 patients with EGC who underwent radical gastrectomy for gastric cancer at Peking University Cancer Hospital from November 2010 to November 2020 with postoperative pathological stage pT1 and complete examination data,were collected.Pearson’s Chi-square test was used and binary logistic regression was employed for univariate and multivariate analyses.Combined analysis of multiple risk and protective factors for lymph node metastasis(LNM)of EGC was performed.A negative predictive value(NPV)combination model was built and validated.Results:LNM occurred in 85 of 561 patients with EGC,and the LNM rate was 15.15%.NPV for LNM reached 100%based on three characteristics,including ulcer-free,moderately well differentiation and patient<65years old or tumor located at the proximal 1/3 of the stomach.Regarding lymphatic basin metastasis,multivariate analysis showed that the metastatic proportion of the left gastric artery lymphatic basin was significantly higher in male patients compared with female patients(65.96%vs.38.89%,P<0.05).The proportion of right gastroepiploic artery lymphatic basin metastasis in patients with a maximum tumor diameter>2 cm was significantly greater than that noted in patients with a maximum tumor diameter≤2 cm(60.78%vs.28.13%,P<0.05).Conclusions:Characteristics of lymph node stations/basins metastasis will facilitate precise lymph node resection.The NPV for LNM reaches 100%based on the following two conditions:young and middle-aged EGC patients,well-differentiated tumors,and without ulcers;or well-differentiated tumors,without ulcers,and tumors located in the proximal stomach.These findings can be used as the recommended indications for functionpreserving curative gastrectomy and sentinel lymph node navigation surgery.

Geometric Calibration and Image Quality Assessment of High Resolution Dual-Camera Satellite

The evaluation of geometric calibration accuracy of high resolution satellite images has been increasingly recognized in recent years.In order to evaluate geometric accuracy for dual-camera satellite images based on the ground control points(GCP),a rigorous geometric imaging model,which was based on the collinear equation of the probe directional angle and the optimized tri-axial attitude determination(TRIAD)algorithm,is presented.Two reliable test fields in Tianjin and Jinan(China)were utilized for geometric accuracy validation of Pakistan Remote Sensing Satellite-1.The experimental results demonstrate a certain deviation of the on-orbit calibration result from the initial design values of the calibration parameters.Therefore,on-orbit geometric calibration is necessary for optical satellite imagery.Within this research,the geometrical performances including positioning accuracy without/with GCP and band registration of the dual-camera satellite were analyzed in detail,and the results of geometric image quality are assessed and discussed.As a result,it is feasible and necessary to establish such a geometric calibration model to evaluate the geometric quality of dual-camera satellite.

Terminology-centered English for Medical Purpose Teaching

Based on the analysis of the necessity of learning medical terminology, the paper lays special emphasis on the discussion of the terminology-centered teaching practice.

急性肾损伤向慢性肾脏病转变研究进展

虽然一些急性肾损伤(AKI)患者获得了临床痊愈,却仍然会由于肾脏结构的改变以及适应不良性修复而发生肾组织纤维化,从而转变进展至慢性肾脏病(CKD)甚至是终末期肾脏病(ESRD)。因此,早期识别和干预AKI向CKD转变是至关重要的。本文就AKI向CKD转变的危险因素、转变机制、生物标志物和干预措施的研究进展作一综述。

An Efficient Probe for Bacterial Nitroreductase Imaging and Detection Based on NanoLuc-Furimazine Bioluminescent Pair

Comprehensive SummaryThe detection of critical endogenous species, such as bacteria in microenvironments in the body, requires better imaging tools for visualization and monitoring of biological events. Bioluminescence imaging is the most popular strategy for obtaining real-time in living cells and organisms. Herein, we introduced a nitroaryl group on the C-3 position and a hydroxy group at the C-6 phenyl ring on furimazine to report the first bioluminescent probe (7) based on NanoLuc-furimazine bioluminescent pair for the detection of nitroreductase in bacteria. The probe, which possessed up to 560-fold intensity increase with a low detection limit of 16 ng/mL of nitroreductase, has the most efficient uncage efficiency in comparison with other bioluminescent congeners, thus enabling highly selective and sensitive visualization of NTR activity in a panel of clinical priority pathogens. Additionally, imaging of the recombinant strain as well as the NTR from mouse feces indicated the potential of this probe in the application of different mouse disease models.

Lufengpithecus inner ear provides evidence of a common locomotor repertoire ancestral to human bipedalism

Various lines of evidence have been used to infer the origin of human bipedalism,but the paucity of hominoid postcranial fossils and the diversity of inferred locomotor modes have tended to confound the reconstruction of ancestral morphotypes.Examination of the bony labyrinth morphology of the inner ear of extinct and living hominoids provides independent evidence for inferring the evolution of hominoid locomotor patterns.New computed tomography data and morphometric analyses of the Late Miocene ape Lufengpithecus indicate that it and other stem great apes possess labyrinths similar to one another and show that hominoids initially evolved from a positional repertoire that included orthogrady,below-branch forelimb suspension and progression,above-branch bipedalism,climbing,clambering,and leaping(hylobatid-like)to one that comprised above-branch quadrupedalism,below-branch forelimb suspension,vertical climbing,limited leaping,terrestrial quadrupedal running and walking,possibly with knuckle walking,and short bouts of bipedalism(chimpanzee-like).The bony labyrinth morphology of Lufengpithecus indicates that it probably conforms more closely to the last common ancestors of crown hominoids and hominids in its locomotor behavior than do other Miocene hominoids.Human bipedalism evolved from this common archetypal Lufengpithecus-like locomotor repertoire.The low evolutionary rate of semicircular canal morphology suggests that Lufengpithecus experienced a relative stasis in locomotor behavior,probably due to the uplift of the Tibetan Plateau,which created a stable environment in the Miocene of southwestern China.

信号交叉口动态直右车道相位转变清空车道控制方法研究

动态车道可以很好地解决交通上时空分配不均的问题,以减少交通拥堵,提高交叉口通行效率和时空资源利用率。但在动态车道相位转变时存在有一部分车辆还未驶离车道的情况,会对下一相位行驶的车辆造成延误。本文以动态直右车道车辆延误最小为目标,研究主、预信号同相位启亮时间差对车辆延误的影响,考虑道路状况、车流量、车速、车辆选择等因素,建立动态直右车道与主预交通信号协同优化模型。通过多个算例计算,以验证模型的合理性。最终可根据实时交通需求情况生成动态车道的信号优化方案。借助SUMO对优化方案进行仿真验证,将本文优化方法与定时信号配时方法在相同的假设条件下进行对比,实验结果表明,本文模型能更好地降低交叉口平均延误,实现时空利用率最大化。

Scalable and flexible porous hybrid film as a thermal insulating subambient radiative cooler for energy-saving buildings

Passive daytime radiative cooling(PDRC)is one of the promising alternatives to electrical cooling and has a significant impact on worldwide energy consumption and carbon neutrality.Toward real-world applications,however,the parasitic heat input and heat leakage pose crucial challenges to commercial and residential buildings cooling.The integrating of radiative cooling and thermal insulation properties represents an attractive direction in renewable energy-efficient building envelope materials.Herein,we present a hierarchically porous hybrid film as a scalable and flexible thermal insulating subambient radiative cooler via a simple and inexpensive inverse high internal phase emulsion strategy.The as-prepared porous hybrid film exhibits an intrinsic combination of high solar reflectance(0.95),strong longwave infrared thermal emittance(0.97),and low thermal conductivity(31 mW/(m K)),yielding a subambient cooling temperature of~8.4℃ during the night and~6.5℃ during the hot midday with an average cooling power of~94 W/m^(2) under a solar intensity of~900 W/m^(2).Promisingly,combining the superhydrophobicity,durability,superelasticity,robust mechanical strength,and industrial applicability,the film is favorable for large-scale,sustainable and energy-saving applications in a wide variety of climates and complicated surfaces,enabling a substantial reduction of energy costs,greenhouse gas emission and associated ozone-depleting from traditional cooling systems.

Risks Associated with Misuse of Ketamine as a Rapid-Acting Antidepressant

Abstract Major depression is a serious psychiatric disorder and remains a leading cause of disability worldwide. Con- ventional antidepressants take at least several weeks to achieve a therapeutic response and this lag period has hin- dered their ability to attain beneficial effects in depressed individuals at high risk of suicide. The non-competitive N- methyl-D-aspartate glutamate receptor antagonist ketamine has been shown to have rapid antidepressant effects in both rodents and humans. The emergence of ketamine as a fast- acting antidepressant provides promising new insights into the development of a rapid treatment response in patients with clinical depression. However, its safety and toxicity remain a concem. In this review, we focus on the limitations of ketamine, including neurotoicity, cognitive dysfunction, adverse events associated with mental status, psy- chotomimetic effects, cardiovascular events, and uropathic effects. Studies have shown that its safety and tolerability profiles are generally good at low doses and with short-term treatment in depressed patients. The adverse events associ- ated with ketamine usually occur with very high doses that are administered for prolonged periods of time and can be relieved by cessation. The antidepressant actions of its two enantiomers, S-ketamine （esketamine） and R-ketamine, are also discussed. R-ketamine has greater antidepressantactions than S-ketamine, without ketamine-related side- effects. Future treatment strategies should consider using R- ketamine for the treatment of depressed patients to decrease the risk of adverse events associated with long-term keta- mine use.