大麦虫和黄粉虫转化塑料效率对比及饲料配比优化

为探究不同“聚苯乙烯-麦麸”饲料配比下对大麦虫、黄粉虫及两种昆虫混合种群对塑料取食效率、取食后的存活、发育情况,以及降解聚苯乙烯的最佳饲料配比,本实验共设置5个处理Feed1(1∶9),Feed2(3∶7),Feed3(5∶5),CK1(10∶0),CK2(0∶10)。结果表明,大麦虫和黄粉虫的生长性能及聚苯乙烯取食量随着聚苯乙烯含量的升高而降低。混合饲养大麦虫和黄粉虫比单独饲养更有助于降解更多的聚苯乙烯,取食率高达(77.03±3.25)%,但混合饲养中的黄粉虫存活率极低,低至(8.67±2.82)%。单独饲养的黄粉虫存活率较其他饲虫比高,高达(81.33±2.59)%,但其聚苯乙烯取食率最高仅为(28.22±2.96)%,远不及单独饲养的大麦虫。在实验期间,黄粉虫化蛹率最高为(77.67±3.85)%,而大麦虫未出现化蛹现象,大麦虫幼虫的生长周期比黄粉虫幼虫长(幼虫期取食塑料),所以大麦虫对塑料的取食情况较好。而单独饲养的大麦虫,Feed1(1∶9)的存活率和聚苯乙烯的取食率均最高,分别为(44.67±1.81)%、(66.18±2.26)%。综上,单独饲养的大麦虫的Feed1(1∶9)配比较优,既能保证大麦虫的正常生长发育,又能降解较多的聚苯乙烯,可为规模化养殖大麦虫、黄粉虫以及降解塑料提供实验依据。

Optimize Purcell filter design for reducing influence of fabrication variation

To protect superconducting qubits and enable rapid readout, optimally designed Purcell filters are essential. To suppress the off-resonant driving of untargeted readout resonators, individual Purcell filters are used for each readout resonator.However, achieving consistent frequency between a readout resonator and a Purcell filter is a significant challenge. A systematic computational analysis is conducted to investigate how fabrication variation affects filter performance, through focusing on the coupling capacitor structure and coplanar waveguide(CPW) transmission line specifications. The results indicate that the T-type enclosing capacitor(EC), which exhibits lower structural sensitivity, is more advantageous for achieving target capacitance than the C-type EC and the interdigital capacitor(IDC). By utilizing a large-sized CPW with the T-type EC structure, fluctuations in the effective coupling strength can be reduced to 10%, given typical micro-nanofabrication variances. The numerical simulations presented in this work minimize the influence of fabrication deviations, thereby significantly improving the reliability of Purcell filter designs.

三自由度类球面并联机构的动力学建模及分析

提出一种可应用于电子装配领域的三自由度(2R1T, R表示旋转, T表示平移)类球面并联机构.该机构由上下2个等半径的动、定平台通过3个相同的RSR(R表示转动副, S表示球关节)支链连接而成.在运动过程中,动平台与定平台始终关于一个中间平面对称,且动平台可绕着对称面内的任意轴线连续旋转和沿着两平台中心连线方向连续平移.基于机构特殊的几何对称性,建立了其等效运动学模型,在此基础上运用Lagrange方法建立了机构的动力学模型,并通过具体的运动算例,利用Mathematica计算和ADAMS(Automatic Dynamic Analysis of Mechanical Systems,机械系统动力学自动分析)仿真验证了该动力学模型的正确性和有效性,为进一步研究机构的动态特性及系统运动控制提供理论指导.

Improvement of Beam Energy Measurement System for BES-III

The beam energy measurement system is significant and profit for both BES-III detector and BEPC-II accelerator. The detection of the high energy scattering photons is realized by virtue of the Compton backscattering principle. Many advanced techniques and precise instruments are employed to acquire the highly accurate measurement of positron/electron beam energy. During five years’ running period, in order to satisfy the requirement of data taking and enhance the capacity of measurement itself, the upgradation of system is continued, which involves the components reformation of laser and optics subsystem, replacement of view-port of the laser to vacuum insertion subsystem, the usage of electric cooling system for high purity germanium detector, and the refinement of data acquisition and processing subsystem. The upgrading of system guarantees the smooth and effective measuring of beam energy at BEPC-II and accommodates the accurate offline energy values for further physics analysis at BES-III.

预应力锚索锚固力监测点经济高效布设方法研究

预应力锚索锚固力监测点合理布设是提高边坡稳定性监测可靠性的重要手段,在确保边坡稳定安全的同时,可最大程度上节省工程监测成本。现阶段预应力锚索锚固力监测点布设方案设计多依赖工程经验,具有很强的盲目性并且监测成本较大,尤其对于大型高陡边坡,由于挖方量和边坡加固工程量巨大,如何实现高陡边坡预应力锚索锚固力监测点经济高效布设,保证边坡安全高效监测是目前亟需解决的问题。以广东省江门市迎宾西路某高边坡为研究背景,通过研究锚索的群锚效应和锚索失效后的影响范围,确定了监测点之间的合理布设间距。构建了边坡三维模型,通过数值计算,模拟高边坡开挖全过程,由数值计算结果分析边坡开挖过程中变形失稳的潜在危险区域,进行监测点选择型布设。通过上述方法,实现了该段高陡路堑边坡预应力锚索锚固力监测点的经济高效布设。研究表明:基于群锚效应与三维数值模拟方法,提出的预应力锚索合理布设间距与开挖过程中潜在危险区域重点监测相结合的综合布设优化方案,可合理利用材料和空间、大幅节省监测成本,实现边坡的经济、高效监测。研究成果为高陡路堑边坡稳定性监测点合理布设提供了一种新的思路。

Mycoplasma hominis meningitis after operative neurosurgery:A case report and review of literature

BACKGROUND Mycoplasma hominis(M.hominis),which causes central nervous system infections in adults,is very rare.It is also relatively difficult to culture mycoplasma and culturing requires special media,resulting in a high rate of clinical underdiagnosis.Therefore,clinicians often treat patients based on their own experience before obtaining pathogenic results and may ignore infections with atypical pathogens,thus delaying the diagnosis and treatment of patients and increasing the length of hospital stay and costs.CASE SUMMARY A 44-year-old man presented to the hospital complaining of recurrent dizziness for 1 year,which had worsened in the last week.After admission,brain magnetic resonance imaging(MRI)revealed a 7.0 cm×6.0 cm×6.1 cm lesion at the skull base,which was irregular in shape and had a midline shift to the left.Based on imaging findings,meningioma was our primary consideration.After lesion resection,the patient had persistent fever and a diagnosis of suppurative meningitis based on cerebrospinal fluid(CSF)examination.The patient was treated with the highest level of antibiotics(meropenem and linezolid),but the response was ineffective.Finally,M.hominis was detected by next-generation metagenomic sequencing(mNGS)in the CSF.Therefore,we changed the antibiotics to moxifloxacin 0.4 g daily combined with doxycycline 0.1 g twice a day for 2 wk,and the patient had a normal temperature the next day.CONCLUSION Mycoplasma meningitis after neurosurgery is rare.We can use mNGS to detect M.hominis in the CSF and then provide targeted treatment.

On Two Cryogenic Systems of High Purity Germanium Detector

Two cryogenic systems of high purity germanium detector, liquid nitrogen and mechanical cooler, are expounded, to- gether with explanations of merits and demerits for each kind of cooling methods. The resolutions of detector to the characteristic lines of 152Eu under different cooling conditions are studied. The laboratory results indicate that the me- chanical cooler (X-Cooler II) is an ideal replacement candidate for the liquid nitrogen cooling system that is being util- ized by BEMS at BEPC-II.

The correlation of miR-106b in nasopharyngeal carcinoma with cell cycle progression and cell invasion

Objective:To study the correlation of miR-106b in nasopharyngeal carcinoma with cell cycle progression and cell invasion.Methods: Patients who were diagnosed with nasopharyngeal carcinoma by pathological biopsy in Shenmu Hospital between March 2013 and February 2018 were included in the study, and the nasopharyngeal carcinoma tissue and tissue adjacent to nasopharyngeal carcinoma obtained from biopsy were collected, miRNA was extracted to determine miR-106b expression, and RNA was extracted to determine the mRNA expression of cell cycle-related genes and cell invasion-related genes.Results: miR-106b expression as well as FOXC1, CyclinD1, CyclinE, TRIM27, uPAR, PARP1 and MTA1 mRNA expression in nasopharyngeal carcinoma tissues were higher than those in adjacent tissues, CYB5R2, p16, IRF5 and E-cadherin mRNA expression were significantly lower than those in adjacent tissues whereas;CYB5R2, p16, IRF5 and E-cadherin mRNA expression in nasopharyngeal carcinoma tissues with high miR-106b expression were lower than those in nasopharyngeal carcinoma tissues with low miR-106b expression whereas FOXC1, CyclinD1, CyclinE, TRIM27, uPAR, PARP1 and MTA1 mRNA expression were higher than those in nasopharyngeal carcinoma tissues with low miR-106b expression.Conclusion:The lowly expressed miR-106b in nasopharyngeal carcinoma can promote the cell cycle progression and cell invasion in the lesion.

Study of Annealing the Damaged HPGe Detector

High purity germanium detectors have important applications in many fields. Detector’s performance deteriorated significantly due to radiation of neutron. The annealing of damaged HPGe detector is expounded in this monograph. The experiment results indicate that raising the temperature to 70°C for five days, the restoration efficiency can reach 90%.

松南长岭断陷查干花次凹火石岭组火山碎屑岩储层特征及主控因素

松辽盆地南部长岭断陷查干花次凹火石岭组碱性火山碎屑岩储层矿物岩石成分和组构复杂,储层成因机理、成岩作用及主控因素认识不清,制约了优质储层预测和精细刻画,影响了气藏的进一步高效开发。通过镜下观察、全岩矿物分析、压汞和纳米CT扫描,并结合特殊测井,系统开展了岩石学特征、火山岩相特征、储层微观特征和裂缝特征研究。结果表明:研究区主要有脱玻化、溶蚀、蚀变等7种成岩作用,在此基础上明确了查干花次凹火山碎屑岩储层发育主控因素,认为该区火山碎屑岩属于富钠碱性火山岩,碎屑类型、矿物成分和岩石粒度是决定储层品质的物质基础,后期经过脱玻化、溶蚀和蚀变作用产生3种不同类型次生孔隙,同时构造应力作用产生的大量天然裂缝有利于形成次生孔隙,对储层微观渗流起到了改善和沟通作用,形成了具有“三孔一缝”的储层特征和独特的微观渗流场。这一认识对富钠碱性火山碎屑岩储层评价和甜点预测具有一定的指导意义,为气藏后续高效开发奠定了坚实的基础。

Incidence and prognosis of olfactory and gustatory dysfunctions related to SARS-CoV-2 Omicron strain infection in China:A national multicenter survey of 35,566 individuals

Objective:This cross-sectional study aimed to determine the epidemiology of olfactory and gustatory dysfunctions related to COVID-19 in China.Methods:This study was conducted by 45 tertiary Grade-A hospitals in China.Online and offline questionnaire data were obtained from patients infected with COVID-19 between December 28,2022,and February 21,2023.The collected information included basic demographics,medical history,smoking and drinking history,vaccination history,changes in olfactory and gustatory functions before and after infection,and other postinfection symptoms,as well as the duration and improvement status of olfactory and gustatory disorders.Results:Complete questionnaires were obtained from 35,566 subjects.The overall incidence of olfactory and taste dysfunction was 67.75%.Being female or being a cigarette smoker increased the likelihood of developing olfactory and taste dysfunction.Having received four doses of the vaccine or having good oral health or being a alcohol drinker decreased the risk of such dysfunction.Before infection,the average olfactory and taste VAS scores were 8.41 and 8.51,respectively;after infection,they decreased to 3.69 and 4.29 and recovered to 5.83 and 6.55 by the time of the survey.The median duration of dysosmia and dysgeusia was 15 and 12 days,respectively,with 0.5%of patients having symptoms lasting for more than 28 days.The overall self-reported improvement rate was 59.16%.Recovery was higher in males,never smokers,those who received two or three vaccine doses,and those that had never experienced dental health issues,or chronic accompanying symptoms.Conclusions:The incidence of dysosmia and dysgeusia following infection with the SARS-CoV-2 virus is high in China.Incidence and prognosis are influenced by several factors,including sex,SARS-CoV-2 vaccination,history of head-facial trauma,nasal and oral health status,smoking and drinking history,and the persistence of accompanying symptoms.

JUNO sensitivity on proton decay p→νK^(+)searches

The Jiangmen Underground Neutrino Observatory(JUNO)is a large liquid scintillator detector designed to explore many topics in fundamental physics.In this study,the potential of searching for proton decay in the p→νK^(+)mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification.Moreover,the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals.Based on these advantages,the detection efficiency for the proton decay via p→νK^(+)is 36.9%±4.9%with a background level of 0.2±0.05(syst)±0.2(stat)events after 10 years of data collection.The estimated sensitivity based on 200 kton-years of exposure is 9.6×1033 years,which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies.

Communication security of autonomous ground vehicles based on networked control systems:The optimized LMI approach

The paper presents a study of networked control systems(NCSs)that are subjected to periodic denial-of-service(DoS)attacks of varying intensity.The use of appropriate Lyapunov-Krasovskii functionals(LKFs)help to reduce the constraints of the basic conditions and lower the conservatism of the criteria.An optimization problem with constraints is formulated to select the trigger threshold,which is solved using the gradient descent algorithm(GDA)to improve resource utilization.An intelligent secure event-triggered controller(ISETC)is designed to ensure the safe operation of the system under DoS attacks.The approach is validated through experiments with an autonomous ground vehicle(AGV)system based on the Simulink platform.The proposed method offers the potential for developing effective defense mechanisms against DoS attacks in NCSs.

The modification toward excited-state dynamics and catalytic activity by isomeric Au_(44)clusters

The structure determination of metal nanoclusters protected by ligands is critical in understanding their physical and chemical properties,yet it remains elusive how the metal core and ligand of metal clusters cooperatively contribute to the observed performances.Here,with the successful synthesis of Au_(44)TBPA_(22)Cl_(2)cluster(TBPA=4-tert-butylphenylacetylene),the structural isomer of previously reported Au_(44)L_(28)clusters(L denoted as ligand)is filled,thereby providing an opportunity to explore the property evolution rules imparted by different metal core structures or different surface ligands.Time-resolved transient absorption spectroscopy reveals that the difference in the core structure between Au_(44)TBPA_(22)Cl_(2)and Au_(44)L_(28)can bring nearly 360 times variation of excited-state lifetime,while only 3–24 times differences in excited-state lifetimes of the three Au_(44)L_(28)nanoclusters with identical metal core but different ligands are observed,which is due to much stronger impact of the metal core than the surface ligands in the electronic energy bands of the clusters.In addition,the Au_(44)clusters protected by alkyne ligands are shown to be highly effective toward the electrochemical oxidation of ethanol,compared to the Au_(44)clusters capped by thiolates,which is ascribed to smaller charge transfer impedance of the former clusters.We anticipate that the study will enhance the process in controlling the nanomaterial properties by precisely tailoring metal core or surface patterns.

Intramolecular hydroamination of alkynes driven by isomeric Au_(36)(SR)_(24)nanocluster catalysts

It remains elusive to realize the distinct catalysis of isomeric catalysts because it becomes challenging to identify structural isomers in the polydisperse nanoparticles.Herein we investigate catalysis of two geometric isomers for 36-gold-atom nanoclusters with different Au cores arrangements but the same thiolate ligands,thereby providing access to isomer catalysts readily participate in a desired reaction.Compared to the Au_(36)(SR)_(24)with a one-dimensional(1D)layout of Au4 tetrahedral units,the Au_(36)(SR)_(24)with a two-dimensional(2D)layout of Au4 tetrahedral units is more effective for the intramolecular hydroamination of alkyne.Our study suggests that the exposed Au sties of the two Au_(36)(SR)_(24)catalysts favor different reaction intermediates and pathways.The intramolecular H transfer leads to intermediates with the C-N and with C=N for the 1D and 2D Au_(36)(SR)_(24)respectively,and hence the different on-site and off-site pathways for the successive reaction steps account for the different performances of the two Au_(36)(SR)_(24)catalysts.

The atomic path for constructing single-helical superstructure of AuCu bimetallic nanoclusters

Single-helical or double-helical structures are common in living organisms.Helical assembly has been found in the artificial nanoparticles,but how they do so remains poorly understood.Here,we exploit atomically precise Au_(6)Cu_(6)bimetallic nanoparticles(or called nanoclusters)as building blocks to construct a single-helical Au_(12)Cu_(12)superstructure in an operative path,thereby providing access to currently elusive mechanistic pathways.We propose that the thermodynamically viable linearto-bent process at a couple of Au_(6)Cu_(6)nanoclusters imparted by the organic ligands seems to be critical for the helical-nanostructured arrangement of Au_(12)Cu_(12).This study could help to offer a new design rule for the exquisitely helical structure assembled from the artificial nanoparticles.

Electrocatalytic and photocatalytic applications of atomically precise gold-based nanoclusters

With advances in cluster chemistry,atomically precise gold nanoclusters(NCs)with well-defined composition and tunable structure provide an exciting opportunity to uncover the specific roles of the geometrical and electronic structures as well as the capped ligands in overall catalytic performances.The Au NCs possess quantum energy levels and unique optical properties,which have exhibited unexpected photocatalytic and electrocatalytic activities.In this review,we first highlight the electrocatalytic applications of Au NCs,including hydrogen evolution reaction,oxygen reduction reaction,CO_2 reduction and catalytic oxidation reactions,and then present Au NCs-driven photocatalytic applications such as selective organic reactions,decomposition of pollutants and energy conversion reactions.Finally,we conclude this review with a brief perspective on the catalytic field of Au NCs.

The biological responses and mechanisms of endothelial cells to magnesium alloy

Due to its good biocompatibility and degradability,magnesium alloy(Mg alloy)has shown great promise in cardiovascular stent applications.Rapid stent re-endothelialization is derived from migrated and adhered endothelial cells(ECs),which is an effective way to reduce late thrombosis and inhibit hyperplasia.However,fundamental questions regarding Mg alloy affecting migration and adhesion of ECs are not fully understood.Here,we evaluated the effects of Mg alloy on the ECs proliferation,adhesion and migration.A global gene expression profiling of ECs co-culturing with Mg alloy was conducted,and the adhesion-and migration-related genes were examined.We found that Mg alloy had no adverse effects on ECs viability but significantly affected ECs migration and adhesion.Co-cultured with Mg alloy extract,ECs showed contractive adhesion morphology and decreased motility,which was supported by the down-regulation of adhesion-related genes(Paxillin and Vinculin)and migration-related genes(RAC 1,Rho A and CDC 42).Accordingly,the re-endothelialization of Mg alloy stent was inhibited in vivo.Our results may provide new inspiration for improving the broad application of Mg alloy stents.

Feasibility and physics potential of detecting ^(8)B solar neutrinos at JUNO

The Jiangmen Underground Neutrino Observatory(JUNO)features a 20 kt multi-purpose underground liquid scintillator sphere as its main detector.Some of JUNO's features make it an excellent location for^8B solar neutrino measurements,such as its low-energy threshold,high energy resolution compared with water Cherenkov detectors,and much larger target mass compared with previous liquid scintillator detectors.In this paper,we present a comprehensive assessment of JUNO's potential for detecting^8B solar neutrinos via the neutrino-electron elastic scattering process.A reduced 2 MeV threshold for the recoil electron energy is found to be achievable,assuming that the intrinsic radioactive background^(238)U and^(232)Th in the liquid scintillator can be controlled to 10^(-17)g/g.With ten years of data acquisition,approximately 60,000 signal and 30,000 background events are expected.This large sample will enable an examination of the distortion of the recoil electron spectrum that is dominated by the neutrino flavor transformation in the dense solar matter,which will shed new light on the inconsistency between the measured electron spectra and the predictions of the standard three-flavor neutrino oscillation framework.IfDelta m^(2)_(21)=4.8times10^(-5);(7.5times10^(-5))eV^(2),JUNO can provide evidence of neutrino oscillation in the Earth at approximately the 3sigma(2sigma)level by measuring the non-zero signal rate variation with respect to the solar zenith angle.Moreover,JUNO can simultaneously measureDelta m^2_(21)using^8B solar neutrinos to a precision of 20% or better,depending on the central value,and to sub-percent precision using reactor antineutrinos.A comparison of these two measurements from the same detector will help understand the current mild inconsistency between the value of Delta m^2_(21)reported by solar neutrino experiments and the KamLAND experiment.

Annealing restoration of HPGe detector

Introduction HPGe detector is used widely,its property is affected by neutron.Annealing to the germanium crystal is a good approach to recover the detector.Purpose To raise the temperature of germanium crystal to recover the resolution for the HPGe detector.Method A special copper ingot is designed and manufactured to increase the heating efficiency.Two temperature controlled power supplies are used to heat the germanium crystal and keep the temperature for cooling rod.Conclusion The experiment results indicate that raising temperature to 70℃for five days,the restoration efficiency is better than 90%.