bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spin‐Torque Memristors Based on Perpendicular Magnetic Tunnel Junctions for Neuromorphic Computing
Authors: Zhang Xueying , Cai Wenlong , Wang Mengxing , Pan Biao , Cao Kaihua , Guo Maosen , Zhang Tianrui , Cheng Houyi , Li Shaoxin , Zhu Daoqian , Wang Lin , Shi Fazhan , Du Jiangfeng , Zhao Weisheng 
Published: March 2021

AbstractSpin‐torque memristors are proposed in 2009, and can provide fast, low‐power, and infinite memristive behavior for neuromorphic computing and large‐density non‐volatile memory. However, the strict requirements of combining high magnetoresistance, stable domain wall pinning and current‐induced switching in a single device pose difficulties in physical implementation. Here, a nanoscale spin‐torque memristor based on a perpendicular‐anisotropy magnetic tunnel junction with a CoFeB/W/CoFeB composite free layer structure is experimentally demonstrated. Its tunneling magnetoresistance is higher than 200%, and memristive behavior can be realized by spin‐transfer torque switching. Memristive states are retained by strong domain wall pinning effects in the free layer. Experiments and simulations suggest that nanoscale vertical chiral spin textures can form around clusters of W atoms under the combined effect of opposite Dzyaloshinskii–Moriya interactions and the Ruderman–Kittel–Kasuya–Yosida interaction between the two CoFeB free layers. Energy fluctuation caused by these textures may be the main reason for the strong pinning effect. With the experimentally demonstrated memristive behavior and spike‐timing‐dependent plasticity, a spiking neural network to perform handwritten pattern recognition in an unsupervised manner is simulated. Due to advantages such as long endurance and high speed, the spin‐torque memristors are competitive in the future applications for neuromorphic computing.
Modulating Nanoinhomogeneity at Electrode–Solid Electrolyte Interfaces for Dendrite‐Proof Solid‐State Batteries and Long‐Life Memristors
Authors: Lu Ziheng , Yang Ziwei , Li Cheng , Wang Kai , Han Jinlong , Tong Peifei , Li Guoxiao , Vishnugopi Bairav Sabarish , Mukherjee Partha P. , Yang Chunlei , Li Wenjie 
Published: March 2021

AbstractDendrite penetration in ceramic lithium conductors severely constrains the development of solid‐state batteries (SSBs) while its nanoscale origin remains unelucidated. An in situ nanoscopic electrochemical characterization technique is developed based on conductive‐atomic force microscopy (c‐AFM) to reveal the local dendrite growth kinetics. Using Li7La3Zr2O12 (LLZO) as a model system, significant local inhomogeneity is observed with a hundredfold decrease in the dendrite triggering bias at grain boundaries compared with that at grain interiors. The origin of the local weakening is assigned to the nanoscale variation of elastic modulus and lithium flux detouring. An ionic‐conductive polymeric homogenizing layer is designed which achieves a high critical current density of 1.8 mA cm–2 and a low interfacial resistance of 14 Ω cm2. Practical SSBs based on LiFePO4 cathodes can be stably cycled over 300 times. Beyond this, highly reversible electrochemical dendrite healing in LLZO is discovered using the c‐AFM electrode, based on which a model memristor with a high on/off ratio of ≈105 is demonstrated for >200 cycles. This work not only provides a novel tool to investigate and design interfaces in SSBs but also offers opportunities for solid electrolytes beyond energy applications.
Essential updates 2019/2020: Multimodal treatment of localized pancreatic adenocarcinoma: Current topics and updates in survival outcomes and prognostic factors
Authors: Kato Hiroyuki , Horiguchi Akihiko , Ito Masahiro , Asano Yukio , Arakawa Satoshi 
Published: March 2021

AbstractOverall survival of patients with localized pancreatic ductal adenocarcinoma (PDAC) is extremely poor. Therefore, the establishment of multimodal treatment strategies is indispensable for PDAC patients because surgical treatment alone could not contribute to the improvement of survival. In this review article, we focus on the current topics and advancement of the treatments for localized PDAC including resectable, borderline resectable, and locally advanced PDAC in accordance with the articles mainly published from 2019 to 2020. Reviewing the articles, the recent progress of multimodal treatments notably improves the prognosis of patients with localized PDAC. For resectable PDAC, neoadjuvant chemo or chemoradiation therapy, rather than upfront surgery, plays a key role, especially in patients with a large tumor, poor performance status, high tumor marker levels, peripancreatic lymph nodes metastasis, or neural invasion suspected on preoperative imaging. For borderline resectable PDAC, neoadjuvant treatments followed by surgery is a desirable approach, and maintenance of immunonutritional status during the treatments are also important. For locally advanced disease, conversion surgery has a central role in improving a survival outcome; however, its indication should be standardized.
Impact of a crime prevention ordinance for small retail establishments
Authors: Davis Jonathan , Casteel Carri , Menéndez Cammie C. 
Published: March 2021

AbstractBackgroundOrdinances requiring the implementation of robbery prevention measures have been enacted at the city level in many jurisdictions. We evaluated the impact of an ordinance requiring crime prevention measures on subsequent crime rates.MethodsCrime reports for robbery and aggravated assault from January 2006 through December 2015 were linked to randomly‐selected convenience stores and small retail grocers in Houston (n = 293). Store characteristics and compliance with a list of safety measures were collected by surveyors in 2011. Generalized linear mixed models were used to compare rates of crime before and after the implementation of the ordinance.ResultsRobberies decreased significantly after the ordinance went into effect (rate ratio = 0.38; 95% confidence interval 0.29–0.51). No individual safety measure was associated with decreased robbery rates. No similar decrease was observed for aggravated assault.ConclusionsCity ordinances mandating crime prevention measures can be effective. We could not parse out the effectiveness of individual elements, suggesting a comprehensive approach may be more effective.
Ultraviolet radiation and risk of cutaneous melanoma and squamous cell carcinoma in males and females in the Norwegian Offshore Petroleum Workers cohort
Authors: Liu Fei‐Chih , Grimsrud Tom K. , Veierød Marit B. , Robsahm Trude E. , Ghiasvand Reza , Babigumira Ronnie , Shala Nita K. , Stenehjem Jo S. 
Published: March 2021

AbstractBackgroundIncreased risk of cutaneous melanoma and squamous cell carcinoma (SCC) has been reported among petroleum workers, but few studies include females, exposure data on ultraviolet radiation (UVR), and potential confounding factors. We aimed to examine UVR exposure in relation to risk of melanoma and SCC among male and female offshore petroleum workers. We also examined the association between UVR exposure and melanoma (Breslow) thickness.MethodsThe Norwegian Offshore Petroleum Workers (NOPW) cohort (n = 27,917) holds information on sunbathing, indoor tanning, sunburns, sunscreen use, and other lifestyle factors recorded in 1998. Linkage to the Cancer Registry of Norway gave information on cancer diagnosis through 2017. We used Cox and logistic regression to estimate hazard ratios (HRs) of skin cancer and odds ratios (OR) of thick (≥1 mm) melanomas, respectively, with 95% confidence intervals (CIs).ResultsMelanoma risk increased with increasing frequency of sunbathing after age 20 (ptrend = 0.031), sunburn average intensity (ptrend = 0.028), and sunscreen use (HR = 2.16; 95% CI: 1.42 ‐3.27 for almost always vs. never/rarely). The risk of thick melanoma was inversely associated with sunbathing frequency after age 20 (OR = 0.38; 95% CI: 0.16 ‐ 0.90 for ≥4 weeks/year vs. 1 week/year). SCC risk increased with increasing frequency of indoor tanning after age 20 (HR = 2.72; 95% CI: 1.22 ‐ 6.05 for ≥3 times/months vs. never), sunburn average intensity (ptrend < 0.001), and sunscreen use (ptrend < 0.001).ConclusionsOur results support associations between UVR exposure and skin cancer risk in male and female offshore petroleum workers. This occupational group may be especially relevant for targeted sun protection advice.
Severe epileptic encephalopathy associated with compound heterozygosity of THG1L variants in the Ashkenazi Jewish population
Authors: Rabin Rachel , Hirsch Yoel , Johansson Martin M. , Ekstein Joseph , Ekstein Ahron , Pappas John 
Published: March 2021

AbstractTHG1L‐associated autosomal recessive ataxia belongs to a group of disorders that occur due to abnormal mitochondrial tRNA modification. The product of THG1L is the tRNA‐histidine guanylyltransferase 1‐like enzyme that catalyzes the 3′‐5“addition of guanine to the 5”‐end of tRNA‐histidine in the mitochondrion. To date, five individuals with homozygosity for p.(Val55Ala) in THG1L have been reported and presented with mild delays or normal development and cerebellar dysfunction. We present seven individuals with biallelic variants in THG1L. Three individuals were compound heterozygous for the p.(Cys51Trp) and p.(Val55Ala) variants and presented with profound developmental delays, microcephaly, intractable epilepsy, and cerebellar hypoplasia. Four siblings were homozygous for the p.(Val55Ala) variant and presented with cerebellar ataxia with cerebellar vermis hypoplasia, dysarthria, mild developmental delays, and normal/near‐normal cognition. All seven patients were of Ashkenazi Jewish descent. Carrier rates for the two variants were calculated in a cohort of 26,731 Ashkenazi Jewish individuals tested by the Dor Yeshorim screening program. The p.(Cys51Trp) variant is novel and was found in 40 of the Ashkenazi Jewish individuals tested, with a carrier rate of 1 in 668 (0.15%). The p.(Val55Ala) variant was found in 229 of the Ashkenazi Jewish individuals tested, with a carrier rate of 1 in 117 (0.85%). The individuals with compound heterozygosity of the p.(Val55Ala) and p.(Cys51Trp) variants expand the phenotypic spectrum of THG1L‐related disorders to include severe epileptic encephalopathy. The individuals with homozygosity of the p.(V55A) variant further establish the associated mild and slowly progressive or nonprogressive neurodevelopmental phenotype.
Trends in the prenatal diagnosis of trisomy 21 show younger maternal age and shift in the distribution of congenital heart disease over a 20‐year period
Authors: Tidrenczel Zsolt , Hajdu Julia , Simonyi Aténé , Szabó István , Ács Nándor , Demeter János , Beke Artúr 
Published: March 2021

AbstractPrenatal testing has changed greatly over the past two decades, which may affect the diagnosis of congenital heart disease (CHD) in Down syndrome. The present study aimed to analyze changes in the prevalence and distribution of CHD diagnosed via ultrasonography and fetopathology in 462 fetuses with trisomy 21 between two consecutive 10‐year periods (1999–2018), as well as the associations between CHDs, ultrasound markers, and extracardiac malformations. Overall, the frequency of cardiovascular malformations in trisomy 21 was 27.7 and 26.5%, and ultrasound identified 70 and 62% of CHDs during these periods. A profound increase in first‐trimester ultrasound findings and associated anomalies with CHDs (ventricular septal defect, Tetralogy of Fallot) since 2009 were observed. Second‐trimester nonstructural heart abnormalities were associated with ultrasound anomalies (74%) and major extracardiac malformations (42.9%). During both study periods, mothers carrying fetuses with CHD were significantly younger than those without CHD (p = 0.038, p = 0.009, respectively). Comparing the two 10‐year periods, there were no changes in the prevalence and detection of CHDs. Trend analysis revealed that, although the frequency of CHD remained stable, the diagnostic spectrum had shifted between the study periods. Detection of nonstructural heart abnormalities necessitates detailed follow‐up for cardiac/extracardiac malformations and chromosomal disorders.
Schizophrenia risk alleles often affect the expression of many genes and each gene may have a different effect on the risk: A mediation analysis
Authors: Peng Xi , Bader Joel S. , Avramopoulos Dimitrios 
Published: March 2021

AbstractVariants identified by genome‐wide association studies (GWAS) are often expression quantitative trait loci (eQTLs), suggesting they are proxies or are themselves regulatory. Across many data sets, analyses show that variants often affect multiple genes. Lacking data on many tissue types, developmental time points, and homogeneous cell types, the extent of this one‐to‐many relationship is underestimated. This raises questions on whether a disease eQTL target gene explains the genetic association or is a bystander and puts into question the direction of expression effect of on the risk, since the many variants‐regulated genes may have opposing effects, imperfectly balancing each other. We used two brain gene expression data sets (CommonMind and BrainSeq) for mediation analysis of schizophrenia‐associated variants. We confirm that eQTL target genes often mediate risk but the direction in which expression affects risk is often different from that in which the risk allele changes expression. Of 38 mediator genes significant in both data sets 33 showed consistent mediation direction (Chi2 test p = 6 × 10−6). One might expect that the expression would correlate with the risk allele in the same direction it correlates with the disease. For 15 of these 33 (45%), however, the expression change associated with the risk allele was protective, suggesting the likely presence of other target genes with overriding effects. Our results identify specific risk mediating genes and suggest caution in interpreting the biological consequences of targeted modifications of gene expression, as not all eQTL targets may be relevant to disease while those that are, might have different from expected directions.
A Facile Synthesized Polymer Featuring B‐N Covalent Bond and Small Singlet‐Triplet Gap for High‐Performance Organic Solar Cells
Authors: Pang Shuting , Wang Zhiqiang , Yuan Xiyue , Pan Langheng , Deng Wanyuan , Tang Haoran , Wu Hongbin , Chen Shanshan , Duan Chunhui , Huang Fei , Cao Yong 
Published: March 2021

AbstractHigh‐efficiency organic solar cells (OSCs) largely rely on polymer donors. Herein, we report a new building block BNT and a relevant polymer PBNT‐BDD featuring B‐N covalent bond for application in OSCs. The BNT unit is synthesized in only 3 steps, leading to the facile synthesis of PBNT‐BDD. When blended with a nonfullerene acceptor Y6‐BO, PBNT‐BDD afforded a power conversion efficiency (PCE) of 16.1 % in an OSC, comparable to the benzo[1,2‐b:4,5‐b′]dithiophene (BDT)‐based counterpart. The nonradiative recombination energy loss of 0.19 eV was afforded by PBNT‐BDD. PBNT‐BDD also exhibited weak crystallinity and appropriate miscibility with Y6‐BO, benefitting of morphological stability. The singlet–triplet gap (ΔEST) of PBNT‐BDD is as low as 0.15 eV, which is much lower than those of common organic semiconductors (≥0.6 eV). As a result, the triplet state of PBNT‐BDD is higher than the charge transfer (CT) state, which would suppress the recombination via triplet state effectively.
High‐Throughput Electron Diffraction Reveals a Hidden Novel Metal–Organic Framework for Electrocatalysis
Authors: Ge Meng , Wang Yanzhi , Carraro Francesco , Liang Weibin , Roostaeinia Morteza , Siahrostami Samira , Proserpio Davide M. , Doonan Christian , Falcaro Paolo , Zheng Haoquan , Zou Xiaodong , Huang Zhehao 
Published: March 2021

AbstractMetal‐organic frameworks (MOFs) are known for their versatile combination of inorganic building units and organic linkers, which offers immense opportunities in a wide range of applications. However, many MOFs are typically synthesized as multiphasic polycrystalline powders, which are challenging for studies by X‐ray diffraction. Therefore, developing new structural characterization techniques is highly desired in order to accelerate discoveries of new materials. Here, we report a high‐throughput approach for structural analysis of MOF nano‐ and sub‐microcrystals by three‐dimensional electron diffraction (3DED). A new zeolitic‐imidazolate framework (ZIF), denoted ZIF‐EC1, was first discovered in a trace amount during the study of a known ZIF‐CO3‐1 material by 3DED. The structures of both ZIFs were solved and refined using 3DED data. ZIF‐EC1 has a dense 3D framework structure, which is built by linking mono‐ and bi‐nuclear Zn clusters and 2‐methylimidazolates (mIm−). With a composition of Zn3(mIm)5(OH), ZIF‐EC1 exhibits high N and Zn densities. We show that the N‐doped carbon material derived from ZIF‐EC1 is a promising electrocatalyst for oxygen reduction reaction (ORR). The discovery of this new MOF and its conversion to an efficient electrocatalyst highlights the power of 3DED in developing new materials and their applications.
Neutralizing Aptamers Block S/RBD‐ACE2 Interactions and Prevent Host Cell Infection
Authors: Liu Xiaohui , Wang Yi‐ling , Wu Jacky , Qi Jianjun , Zeng Zihua , Wan Quanyuan , Chen Zhenghu , Manandhar Pragya , Cavener Victoria S. , Boyle Nina R. , Fu Xinping , Salazar Eric , Kuchipudi Suresh V. , Kapur Vivek , Zhang Xiaoliu , Umetani Michihisa , Sen Mehmet , Willson Richard C. , Chen Shu‐hsia , Zu Youli 
Published: March 2021

AbstractThe receptor‐binding domain (RBD) of the severe acute respiratory syndrome coronavirus 2 spike (S) protein plays a central role in mediating the first step of virus infection to cause disease: virus binding to angiotensin‐converting enzyme 2 (ACE2) receptors on human host cells. Therefore, S/RBD is an ideal target for blocking and neutralization therapies to prevent and treat coronavirus disease 2019 (COVID‐19). Using a target‐based selection approach, we developed oligonucleotide aptamers containing a conserved sequence motif that specifically targets S/RBD. Synthetic aptamers had high binding affinity for S/RBD‐coated virus mimics (KD≈7 nM) and also blocked interaction of S/RBD with ACE2 receptors (IC50≈5 nM). Importantly, aptamers were able to neutralize S protein‐expressing viral particles and prevent host cell infection, suggesting a promising COVID‐19 therapy strategy.
Biogenesis‐Guided Synthesis and Structural Revision of Sarocladione Enabled by Ruthenium‐Catalyzed Endoperoxide Fragmentation
Authors: Ning Yuhan , Tian Hailong , Gui Jinghan 
Published: March 2021

AbstractSarocladione is the first 5,10:8,9‐diseco‐steroid with a 14‐membered macrocyclic diketone framework to have been isolated from a natural source. Herein we report a biomimetic synthesis of sarocladione in only two or seven steps from inexpensive, commercially available ergosterol. The key feature of this synthesis was a novel ruthenium‐catalyzed endoperoxide fragmentation, which transformed various saturated endoperoxides into olefinic diketones by cleavage of two C−C bonds. This synthesis allowed us to unambiguously determine the structure of sarocladione and provided experimental support for its revised biosynthetic origin. This work also vividly demonstrates that consideration of the biogenesis is a powerful tool for elucidating the structures of natural products.
An Area‐Specific, International Community‐Led Approach to Understanding and Addressing Equality, Diversity, and Inclusion Issues within Supramolecular Chemistry
Authors: Caltagirone Claudia , Draper Emily R. , Hardie Michaele J. , Haynes Cally J. E. , Hiscock Jennifer R. , Jolliffe Katrina A. , Kieffer Marion , McConnell Anna J. , Leigh Jennifer S. 
Published: March 2021

AbstractDiversity, equality, and inclusion (DEI/EDI) are pressing issues in chemistry and the natural sciences. In this Essay we share how an area‐specific approach is “calling in” the community so that it can act to address EDI issues, and support those who are marginalised. Women In Supramolecular Chemistry (WISC) is an international network that aims to support equality, diversity, and inclusion within supramolecular chemistry. WISC has taken a field‐specific approach using qualitative research methods with scientists to identify the support that is needed and the problems the supramolecular community needs to address. Herein, we present survey data from the community which highlight the barriers that are faced by those who take career breaks for any reason, a common example is maternity leave, and the importance of mentoring to aid progression post‐PhD. In conclusion, we set out an interdisciplinary and creative approach to addressing EDI issues within supramolecular chemistry.
Linking the Dynamic Chemical State of Catalysts with the Product Profile of Electrocatalytic CO2 Reduction
Authors: Wang Jiali , Tan Hui‐Ying , Zhu Yanping , Chu Hang , Chen Hao Ming 
Published: March 2021

AbstractThe promoted activity and enhanced selectivity of electrocatalysts is commonly ascribed to specific structural features such as surface facets, morphology, and atomic defects. However, unraveling the factors that really govern the direct electrochemical reduction of CO2 (CO2RR) is still very challenging since the surface state of electrocatalysts is dynamic and difficult to predict under working conditions. Moreover, theoretical predictions from the viewpoint of thermodynamics alone often fail to specify the actual configuration of a catalyst for the dynamic CO2RR process. Herein, we re‐survey recent studies with the emphasis on revealing the dynamic chemical state of Cu sites under CO2RR conditions extracted by in situ/operando characterizations, and further validate a critical link between the chemical state of Cu and the product profile of CO2RR. This point of view provides a generalizable concept of dynamic chemical‐state‐driven CO2RR selectivity that offers an inspiration in both fundamental understanding and efficient electrocatalysts design.
Triblock SEBS/DVB crosslinked and sulfonated membranes: Fuel cell performance and conductivity
Authors: Teruel‐Juanes Roberto , del Río Carmen , Gil‐Castell Oscar , Primaz Carmem , Ribes‐Greus Amparo 
Published: March 2021

AbstractA set of styrene‐ethylene‐butylene‐styrene triblock copolymer (SEBS) membranes with 10 or 25 wt% divinyl‐benzene (DVB) as a crosslinking agent were prepared and validated. Physicochemical characterization revealed suitable hydrolytic and thermal stability of photo‐crosslinked membranes containing 25 wt% DVB and post‐sulfonated. These compositions were evaluated in H2/O2 single cells, and electrical and proton conductivities were furtherly assessed. The membranes with the milder post‐sulfonation showed greater proton conductivity than those with excessive sulfonation. In terms of electrical conductivity, a universal power law was applied, and the values obtained were low enough for being used as polyelectrolytes. At the analyzed temperatures, the charge transport process follows a long‐range pathway or vehicular model. Finally, fuel cell performance revealed the best behavior for the membrane with 25 wt% DVB, photo‐crosslinked during 30 min and mild sulfonated, with a promising power density of 526 mW·cm−2. Overall, the results obtained highlight the promising fuel cell performance of these cost‐effective triblock copolymer‐based membranes and indicate that higher sulfonation does not necessarily imply better power density.