Rising utilization of stable isotopes in tree rings for climate change and forest ecology

Analyses of stable isotopes(C,O,H)in tree rings are increasingly important cross-disciplinary programs.The rapid development in this field documented in an increasing number of publications requires a comprehensive review.This study includes a bibliometric analysis-based review to better understand research trends in tree ring stable isotope research.Overall,1475 publications were selected from the Web of Science Core Collection for 1974-2023.The findings are that:(1)numbers of annual publications and citations increased since 1974.From 1974 to 1980,there were around two relevant publications per year.However,from 2020 to 2022,this rose sharply to 109 publications per year.Likewise,average article citations were less than four per year before 1990,but were around four per article per year after 2000;(2)the major subjects using tree ring stable isotopes include forestry,geosciences,and environmental sciences,contributing to 42.5%of the total during 1974-2023;(3)the top three most productive institutions are the Chinese Academy of Sciences(423),the Swiss Federal Institute for Forest,Snow and Landscape Research(227),and the University of Arizona(204).These achievements result from strong collaborations;(4)review papers,for example,(Dawson et al.,Annu Rev Ecol Syst 33:507-559,2002)and(McCarroll and Loader,Quat Sci Rev 23:771-801,2004),are among the most cited,with more than 1000 citations;(5)tree ring stable isotope studies mainly focus on climatology and ecology,with atmospheric CO_(2) one of the most popular topics.Since 2010,precipitation and drought have received increasing attention.Based on this analysis,the research stages,key findings,debated issues,limitations and direc-tions for future research are summarized.This study serves as an important attempt to understand the progress on the use of stable isotopes in tree rings,providing scientific guid-ance for young researchers in this field.

Urolithiasis: From pathogenesis to management (part two)

Embarking on a scholarly exploration of the intricate landscape of urolithiasis,the second part of the special section in the Asian Journal of Urology serves as a continuum to the scholarly discourse initiated in its predecessor.Urolithiasis is a common condition affecting 5%-10%of the global population[1].Despite significant progress in understanding the pathogenesis and management of urolithiasis,it remains a substantial public health concern.The objective of the special section in the Asian Journal of Urology is to provide an updated knowledge on the pathogenesis,diagnosis,and management of urolithiasis.In this part two of the special section,we stillfocus on the aspects of stone pathogenesis,treatment,complications prevention,and the application of new technologies.

Embracing the era of neuromorphic computing

In recent years,deep learning has made tremendous achievements in computer vision,natural language processing,man-machine games and so on,where artificial intelligence can reach or go beyond the level of human beings.However,behind so many glories,some serious challenges exist in the bottom hardware,hindering the further development of Artificial Intelligence.

A review of compact modeling for phase change memory

Phase change memory(PCM)attracts wide attention for the memory-centric computing and neuromorphic comput-ing.For circuit and system designs,PCM compact models are mandatory and their status are reviewed in this work.Macro mod-els and physics-based models have been proposed in different stages of the PCM technology developments.Compact model-ing of PCM is indeed more complex than the transistor modeling due to their multi-physics nature including electrical,thermal and phase transition dynamics as well as their interactions.Realizations of the PCM operations including threshold switching,set and reset programming in these models are diverse,which also differs from the perspective of circuit simulations.For the purpose of efficient and reliable designs of the PCM technology,open issues and challenges of the compact modeling are also discussed.

Body Bias Dependence of Bias Temperature Instability(BTI)in Bulk FinFET Technology

In this article,the body bias dependence of the bias temperature instability(BTI)in bulk FinFETs is experimentally studied,under different test conditions for the first time.In contrast to the traditional understanding that changing body bias has little impact on BTI degradation in FinFETs due to its weak body effect,it is observed that it actually has non-negligible impacts.And a forward body bias(FBB)can reduce the BTI degradation in FinFETs,which is opposite with the trend in planar devices.The underlying physics is found due to the trade-off between two competing factors.The results are helpful for understanding and modeling reliability in FinFETs.

神经形态器件研究进展与未来趋势

大数据时代的信息爆炸、摩尔定律的逐渐减缓和"万物互联"的最终愿景使得发展高性能的非传统计算迫在眉睫. 21世纪以来,神经形态计算以高度的并行、极低的功耗和存算一体的特征受到了广泛的关注.其中,具有独特物理机制的神经形态器件是神经形态计算硬件的基本组成单元,对新型非冯·诺依曼架构芯片的研发乃至类脑智能的最终实现都具有重要意义.本文重点介绍了神经形态器件的研究进展和未来研发的趋势.研究低功耗的神经形态器件与集成方法,提高突触器件的线性度、对称性和开关比以及从动力学角度模拟生物启发的神经系统是该领域的研究热点.

Inhibition of LIM kinase reduces contraction and proliferation in bladder smooth muscle

Overactive bladder(OAB)is the most bothersome symptom in lower urinary tract symptoms(LUTS).Current pharmacologic treatment aims to inhibit detrusor contraction;however,shows unsatisfied efficacy and high discontinuation rate.LIM kinases(LIMKs)promote smooth muscle contraction in the prostate;however,their function in the bladder smooth muscle remains unclear.Here,we studied effects of the LIMK inhibitors on bladder smooth muscle contraction and proliferation both in vitro and in vivo experiments.Bladder expressions of LIMKs are elevated in OAB rat detrusor tissues.Two LIMK inhibitors,SR7826 and LIMKi3,inhibit contraction of human detrusor strip,and cause actin filament breakdown,as well as cell proliferation reduction in cultured human bladder smooth muscle cells(HBSMCs),paralleled by reduced cofilin phosphorylation.Silencing of LIMK1 and LIMK2 in HBSMCs resulted in breakdown of actin filaments and decreased cell proliferation.Treatment with SR7826 or LIMKi3 decreased micturition frequency and bladder detrusor hypertrophy in rats with bladder outlet obstruction.Our study suggests that LIMKs may promote contraction and proliferation in the bladder smooth muscle,which could be inhibited by small molecule LIMK inhibitors.LIMK inhibitors could be a potential therapeutic strategy for OAB-related LUTS.

PREPARATION AND CHARACTERIZATION OF HUMIDITY SENSOR BASED ON POLY(3-ALKYL)PYRROLE CONTAINING PHOSPHONIC ACID GROUPS

Poly（3-alkyl）pyrroles containing phosphonic acid groups with different alkyl segment lengths were chemical synthesized and the properties were measured by FTIR and UV-Vis spectroscopy. FTIR and UV-Vis results showed that the synthesized polymers were in a low doping level through chemical polymerization. By spin-coating on the surface of substrates, the polymer can be used as a humidity sensor. The change of DC electric current of the polypyrroles varies with the chain length of the alkyl substituents. The capacitance increases with the increase of the humidity and resistance decreases with the increase of humidity. This result is different from that ofpolypyrrole without alkyl substituents due to the influence of the phosphonic acid group. The sensor showed the resistive-type at high relative humidity, and the capacitive- type at the low relative humidity. The sensor exhibited very fast response to the change of environment humidity.

Tree ring derived summer temperature variability over the past millennium in the western Himalayas of northern Pakistan

Long-term high resolution climate proxies are essential for understanding climate variability particularly,in regions such as the western Himalayas of northern Pakistan,where few long-term climate records are available.Using standard dendrochronological methods,an 1132-year(882 to 2013 C.E.)tree-ring chronology of Juniperus excelsa M.Bieb was established from the western Himalayas,northern Pakistan(WHNP).Tree growth was negatively and significantly(r=-0.65)correlated with the growing season(June-July)mean temperature,and positively and weakly(r=0.22)associated with precipitation.This inverse relationship of tree radial growth with temperature and positive association with precipitation demonstrated that forest growth is sensitive to high temperature related drought.Utilizing a reliable STD chronology and robust reconstruction model,a 928-year(1086 to 2013 C.E.)mean temperature reconstruction was developed for the WHNP using the substantial negative correlation between the summer temperature and standard tree ring-width chronology.According to statistical validation,the reconstruction accounted for 41.6% of the climatic variation for the period of 1956-2013 C.E.instrumental period.Individual extreme-warm periods occurred in 1093 C.E.(29.42℃)and extreme cold periods in 1088 C.E.(26.99℃)observed during the past 928 years.The reconstruction's multi-taper method(MTM)spectral analysis reveals significant(p<0.05)2-3-year and 63.8-year cycles.Since the 2-3-year cycle occurred within the range of ENSO variation,which indicates that ENSO had an impact on the regional temperature in our studied area.

Compact modeling of quantum confinements in nanoscale gate-all-around MOSFETs

In this work,a surface-potential based compact model focusing on the quantum confinement effects of ultimately scaled gate-all-around(GAA)MOSFET is presented.Energy quantization with sub-band formation along the radius direction of cylindrical GAAs or thickness direction of nanosheet GAAs leads to significant quantization effects.An analytical model of surface potentials is developed by solving the Poisson equation with incorporating sub-band effects.In combination with the existing transport model framework,charge-voltage and current-voltage formulations are developed based on the surface potential.The model formulations are then extensively validated using TCAD numerical simulations as well as Si data of nanosheet GAA MOSFETs.Simulations of typical circuits verify the model robustness and convergence for its applications in GAA technology.