转录组分析在血液样本时间和供体特征刻画中的应用研究

案件现场生物物证信息深度挖掘与刻画,可以为案件侦查、涉案人员查找提供丰富可靠线索,是当前法医DNA检验的有效补充,也是国内外法庭科学的研究热点之一。本研究以血液样本为研究对象,证实了0~168天内离体血液样本转录组变化的时间相关性,并建立随机森林模型实现不同离体时间血液样本分类。同时,进一步证实相同离体时间段内,不同吸烟习惯和不同性别供体来源的血液样本转录本具有显著差异,HLA-DRB1、HLA-DQB1和HLA-DQA2可以作为供体吸烟习惯判别标志,Y染色体非重组区(non-recombining Y,NRY)的转录本RPS4Y1和EIF1AY可以作为供体性别特征判别标志。本研究为法庭科学领域建立基于转录组分析的血液样本遗留时间和供体特征刻画方法提供了理论基础和实验依据。

Impact of Al_(x)Ga_(1-x)N barrier thickness and Al composition on electrical properties of ferroelectric HfZrO/Al_(2)O_(3)/AlGaN/GaN MFSHEMTs

Ferroelectric(FE)HfZrO/Al_(2)O_(3) gate stack AlGaN/GaN metal-FE-semiconductor heterostructure high-electron mo-bility transistors(MFSHEMTs)with varying Al_(x)Ga_(1-x)N barrier thickness and Al composition are investigated and com-pared by TCAD simulation with non-FE HfO_(2)/Al_(2)O_(3) gate stack metal-insulator-semiconductor heterostructure high-electron mobility transistors(MISHEMTs).Results show that the decrease of the two-dimensional electron gas(2DEG)density with decreasing AlGaN barrier thickness is more effectively suppressed in MFSHEMTs than that in MISHEMTs due to the enhanced FE polarization switching efficiency.The electrical characteristics of MFSHEMTs,including transcon-ductance,subthreshold swing,and on-state current,effectively improve with decreasing AlGaN thickness in MFSHEMTs.High Al composition in AlGaN barrier layers that are under 3-nm thickness plays a great role in enhancing the 2DEG den-sity and FE polarization in MFSHEMTs,improving the transconductance and the on-state current.The subthreshold swing and threshold voltage can be reduced by decreasing the AlGaN thickness and Al composition in MFSHEMTs,affording favorable conditions for further enhancing the device.

Population amount risk assessment of extreme precipitation-induced landslides based on integrated machine learning model and scenario simulation

In this study,the future landslide population amount risk(LPAR)is assessed based on integrated machine learning models(MLMs)and scenario simulation techniques in Shuicheng County,China.Firstly,multiple MLMs were selected and hyperparameters were optimized,and the generated 11 models were crossintegrated to select the best model to calculate landslide susceptibility;by calculating precipitation for different extreme precipitation recurrence periods and combining the susceptibility results to assess the landslide hazard.Using the town as the basic unit,the exposure and vulnerability of the future landslide population under different Shared Socioeconomic Pathways(SSPs)scenarios in each town were assessed,and then combined with the hazard to estimate the LPAR in 2050.The results showed that the integrated model with the optimized random forest model as the combination strategy had the best comprehensive performance in susceptibility assessment.The distribution of hazard classes is similar to susceptibility,and with an increase in precipitation,the low-hazard area and high-hazard decrease and shift to medium-hazard and very high-hazard classes.The high-risk areas for future landslide populations in Shuicheng County are mainly concentrated in the three southwestern towns with high vulnerability,whereas the northern towns of Baohua and Qinglin are at the lowest risk class.The LPAR increased with the intensity of extreme precipitation.The LPAR differs significantly among the SSPs scenarios,with the lowest in the“fossil-fueled development(SSP5)”scenario and the highest in the“regional rivalry(SSP3)”scenario.In summary,the landslide susceptibility model based on integrated machine learning proposed in this study has a high predictive capability.The results of future LPAR assessment can provide theoretical guidance for relevant departments to cope with future socioeconomic development challenges and make corresponding disaster prevention and mitigation plans to prevent landslide risks from a developmental perspective.

Quantifying Multi-hazards and Impacts Over Different Growth Periods of Maize:A Study Based on Index Construction

Owing to the complexity and variability of global climate,the study of extreme events to ensure food security is particularly critical.The standardized precipitation requirement index(SPRI)and chilling injury index(I_(Ci))were introduced using data from agrometeorological stations on the Songliao Plain between 1981 and 2020 to identify the spatial and temporal variability of drought,waterlogging,and low-temperature cold damage during various maize growth periods.Compound drought and low-temperature cold damage events(CDLEs)and compound waterlogging and low-temperature cold damage events(CWLEs)were then identified.To measure the intensity of compound events,the compound drought and low-temperature cold damage magnitude index(CDLMI),and compound waterlogging and low-temperature cold damage magnitude index(CWLMI)were constructed by fitting marginal distributions.Finally,the effects of extreme events of various intensities on maize output were examined.The findings demonstrate that:(1)There were significant differences in the temporal trends of the SPRI and ICiduring different maize growth periods.Drought predominated in the middle growth period(MP),waterlogging predominated in the early growth period(EP)and late growth period(LP),and both drought and waterlogging tended to increase in intensity and frequency.The frequency of low-temperature cold damage showed a decreasing trend in all periods.(2)The CDLMI and CWLMI can effectively determine the intensity of CDLEs and CWLEs in the study area;these CDLEs and CWLEs had higher intensity and frequency in the late growth period.(3)Compared to single events,maize relative meteorological yield had a more significant negative correlation with the CDLMI and CWLMI.

锂离子电池极片制造中的微结构演化

锂离子电池是能源领域的革命性创新,具有能量密度高、循环寿命长等优点,推动了新能源、新能源汽车等新兴产业的跨越式发展,并应用于卫星、无人机等国家战略领域,成为世界各国竞争的战略高地.锂离子电池的广泛应用不仅源于新兴能源材料的创新,还与制造工艺及装备技术的进步密不可分.极片制造作为生产锂离子电池最核心的过程,包括制浆、涂布、辊压三大关键工序,制造的正负电极构成了电化学反应载体和整个电池的核心.在电极制造中,多孔多组分电极微结构发生复杂的演化与定构过程,很大程度上决定了单体电池的能量密度、倍率特性等性能.本文分析极片制造中制浆、涂布和辊压技术进展与应用情况,重点讨论电极微结构在制造过程中的演化以及其对电池电化学性能的影响,旨在从“制造工艺-微结构-性能”之间的关系视角形成对电极微结构设计、材料制备、制造工艺的进一步认识,为研发高性能锂离子电池提供指导.

Kerr effect in ultra-compact hybrid plasmonic metal-insulator-metal nano-focusing structure

Nano-focusing structures based on hybrid plasmonic waveguides are likely to play a key role in strong nonlinear optical devices.Although the insertion loss is considerable,a significant nonlinear phase shift may be achieved by decreasing the nano-focusing device footprint and careful parameter optimization.Here,we study the Kerr effect in hybrid plasmonic waveguides by analyzing the mode effective area,energy velocity,and insertion loss.Particularly,by utilizing plasmonics to manipulate the effective index and mode similarity,the TM mode is reflected and absorbed,while the TE mode passes through with relatively low propagation loss.By providing a deep understanding of hybrid plasmonic waveguides for nonlinear applications,we indicate pathways for their future optimization.

Band-gap tunable(Ga_(x)In_(1−x))_(2)O_(3)layer grown by magnetron sputtering

Multicomponent oxide(Ga_(x)In_(1−x))_(2)O_(3)films are prepared on(0001)sapphire substrates to realize a tunable band-gap by magnetron sputtering technology followed by thermal annealing.The optical properties and band structure evolution over the whole range of compositions in ternary compounds(Ga_(x)In_(1−x))_(2)O_(3)are investigated in detail.The X-ray diffraction spectra clearly indicate that(Ga_(x)In_(1−x))_(2)O_(3)films with Ga content varying from 0.11 to 0.55 have both cubic and monoclinic structures,and that for films with Ga content higher than 0.74,only the monoclinic structure appears.The transmittance of all films is greater than 86%in the visible range with sharp absorption edges and clear fringes.In addition,a blue shift of ultraviolet absorption edges from 380 to 250 nm is noted with increasing Ga content,indicating increasing band-gap energy from 3.61 to 4.64 eV.The experimental results lay a foundation for the application of transparent conductive compound(Ga_(x)In_(1−x))_(2)O_(3)thin films in photoelectric and photovoltaic industry,especially in display,light-emitting diode,and solar cell applications.

Rationale and Study Design for Evaluating the Efficacy and Safety of Intracardiac Echocardiography-Guided Minimal-Fluoroscopy Ablation in Patients with Paroxysmal Atrial Fibrillation:A Non-Inferior,Multi-Center,Prospective Randomized Controlled Trial(PAF-ICE Trial)

The feasibility and safety of intracardiac echocardiography(ICE)-guided catheter ablation for atrial fibrillation(AF)using a minimal/zero-fluoroscopy approach have recently been reported.This approach helps to reduce ionizing radiation exposure and orthopedic complications resulting from using lead aprons.The objectives of this planned prospective,multicenter randomized controlled trial(RCT)(paroxysmal AF(PAF)-ICE trial;ChiCTR2000033624)are to evaluate the efficacy and safety of ICE-guided minimal-fluoroscopy ablation in patients with PAF and the impact on occupational hazards among lab staff.Patients will be randomized in a 1:1 ratio to 2 groups:minimal fluoroscopy group(n=216)and traditional approach group(n=216).In the minimal fluoroscopy group,an ICE catheter will be used for geometry/anatomic construction,transseptal puncture,catheter tracking,and effusion monitoring.Pulmonary vein isolation(PVI)will be performed using an open-irrigated radiofrequency SmartTouch Surround Flow or SmartTouch catheter(Biosense Webster,Diamond Bar,California,USA),and confirmed by a multipolar Lasso or PentaRay catheter(Biosense Webster).In the traditional approach group,an ICE catheter will not be used.Transseptal puncture will be performed under fluoroscopic guidance,with all geometries constructed by mapping the catheters.The primary efficacy endpoint is freedom from AF recurrence(without antiarrhythmic medications)at 12months after ablation.Other endpoints include duration of lead apron use,measures of intra-procedural efficiency,and peri-procedural complications.This RCT will evaluate the efficacy and safety of ICE-guided minimal-fluoroscopy ablation in patients with PAF,also evaluate the benefits to lab staff(regarding reducing occupational hazards)related to this“minimal/zero-fluoroscopy”and“leadless”mode.