mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
Identities for degenerate Bernoulli polynomials and Korobov polynomials of the first kind

In this paper, we derive five basic identities for Sheffer polynomials by using generalized Pascal functional and Wronskian matrices. Then we apply twelve basic identities for Sheffer polynomials, seven from previous results, to degenerate Bernoulli polynomials and Korobov polynomials of the first kind and get some new identities. In addition, letting λ → 0 in such identities gives us those for Bernoulli polynomials and Bernoulli polynomials of the second kind.
Recent advances in active sites identification and regulation of M–N/C electro-catalysts towards ORR

Transition metal and nitrogen co-doped carbon (M–N/C) catalysts are recognized as the most prospective alternatives for platinum-based electro-catalysts towards oxygen reduction reaction (ORR) in polymer electrolyte fuel cells. Recently, significant progress has been achieved in the identification and regulation of active sites of this kind of catalysts. In this mini review, we summarize the techniques and strategies to identify active sites in M–N/C catalysts, the main debates on active sites types, the measurement method for active site density, the reactivity descriptors for M–N/C catalysts, and directions to the design of ORR M–N/C catalysts.
人机混合智能专题简介

人工智能这一概念自1956年被首次提出以来,几经起落,近几年重新焕发了勃勃生机,对社会、产业和国防产生越来越重要而广泛的影响.针对当前人工智能面临的挑战性问题 ——要解决问题的不确定性、脆弱性和开放性,中国国务院批准和印发了《新一代人工智能发展规划》,抢抓人工智能发展的重大战略机遇,构筑中国人工智能发展的先发优势,加快建设创新型国家和世界科技强国.
DNA damage in nucleosomes

Eukaryotic genomic DNA is packed into chromatin, whose fundamental structural unit is the nucleosome. As DNA-histone protein complexes, nucleosomes show different properties toward exogenous and endogenous DNA-damaging agents. This review summarizes nucleosome DNA damage due to different sources, including alkylating agents, radicals, UV radiation and reactive DNA damage intermediates. In most cases, the histone core protects the associated DNA against damage via its structure and/or scavenging of damaging agents. In contrast, histones react with damaged DNA and, in some instances, catalyze DNA damage in the nucleosome. The biological consequence of nucleosome DNA damage and future prospects in this field are briefly discussed.
中亚东部晚全新世水文气候变化及可能成因

中亚东部水文气候变化对中纬大气环流非常敏感.为了查明该地区水文气候的长期变化及其与大气环流的关系,文章利用位于中天山深水湖泊——赛里木湖钻孔岩芯,在~(137)Cs、~(210)Pb和AMS~(14)C定年基础上,对湖泊岩芯有机碳、有机氮、碳/氮比、碳酸盐含量和粒度等多指标进行了分析,重建了晚全新世以来该地区水文气候变化历史.结果显示,晚全新世以来共发生了4次降水显著增加时期(4000~3780、3590~3210、2800~2160和890~280cala BP)和1次降水微弱增加时期(1700~1370cal a BP),这与中亚东部地区已有的降水/湿度记录相吻合,表明晚全新世以来该地区具有相似的水文气候变化模式.太阳活动减弱以及整个环北大西洋地区大气环流南移,特别是中纬西风主要路径的南移,可能是中亚东部地区晚全新世水文气候变化的最主要原因.此外,赛里木湖研究结果还揭示了该地区最近100年降水显著增加,但中亚地区未来水文气候如何变化仍需更多不同载体的深入研究.
中国南方植被的变化

为揭示自末次盛冰期以来中国南方植被的变化规律,文章在前人工作的基础上,通过在一些研究薄弱区布钻取芯,建立钻孔剖面高分辨率的时间标尺和孢粉序列,以恢复研究区过去约2万年以来的植被变化过程.文中分别给出中国南方18、9和6ka BP前后的植被分带图和各区域植物的分布特征.研究表明:18ka BP前的植被带分布与现在存在着明显的差异,其中西部由西北向东南依次为寒温性针叶林与高寒草甸草原带、温带针阔叶混交林带/暖温带落叶阔叶林带,中东部由北向南依次分布温带针阔叶混交林带、暖温带落叶阔叶林带,以及北亚热带常绿、落叶阔叶混交林带;9ka BP前后的植被面貌发生了明显的变化,除西北部局部地处山地温性针阔叶混交林带外,其他地区由北向南依次分布北亚热带常绿、落叶阔叶混交林亚带,中亚热带典型常绿阔叶林亚带,南亚热带季风常绿阔叶林亚带/热带季雨林和雨林带;6ka BP前后的植被面貌与9ka BP前后的变化不大,但各个植被带的北缘略有北移,反映当时总体气候变得更加温暖.中国南方2万年以来的植被变化,很大程度上受到环境变迁的驱使,其中气候变化为主要影响因素,人类活动的影响在后期变得越来越明显,而在长江下游和三角洲地区,海平面变化对植物的分布同样构成一定的影响.
末次冰盛期中国西部冰川物质平衡线高度的模拟研究

文章使用9个气候模式的数值试验数据,研究了末次冰盛期中国西部冰川物质平衡线高度(ELA),以期加深理解冰期青藏高原地表环境以及ELA变化成因.相对于工业化革命前期这一参考时段,末次冰盛期青藏高原夏季普遍降温4~8℃,年降水量平均减少25%.在降温和降水减少的共同作用下,中国西部ELA降低,不同区域之间降幅存在差异.在青藏高原地区,其南缘和西北部下降1100m,中部腹地下降650~800m,东部下降550~800m且由西南向东北逐渐变小.中国境内天山上的ELA下降不超过650m,祁连山和阿尔泰山上的下降值在500~600m.另外,水平分辨率高的气候模式能模拟出青藏高原中部ELA下降不超过500m的低值,这与古冰川遗迹记录一致;末次冰盛期青藏高原冰川物质积累区主要发生在边缘山地,其面积扩张至现代的2~5倍,但仍未覆盖到高原中部.
全球城市人居环境不透水面与绿地空间特征制图

全球城市不透水面和绿地空间遥感制图对于准确把握全球人居环境质量,指导城市和区域发展规划,促使城市向生态、宜居和可持续方向发展具有重要的科学意义和应用价值.当前研究中针对全球城市下垫面覆盖状况不透水面与绿地空间要素的高精度遥感制图仍显不足.本研究基于城市等级尺度地表结构和景观分类原理,融合了GlobeLand30数据等,建立了MODIS NDVI、夜间灯光数据(DMSP/OLS)和全球各分区30个典型城市LandsatTM获取的不透水面和绿地空间像元组分比例之间回归关系,发展了全球城市建成区内不透水面和绿地空间组分比例数据集.基于Google Earth高分辨率影像验证表明,城市不透水面制图的平均相对误差(MRE)为0.19.本文评估的全球城市用地面积为76.29×10~4km~2,主要分布于北半球的欧洲中部地区、亚洲东部地区和北美洲的中东部地区,其中北美洲、欧洲和亚洲城市用地面积为66.3×10~4km~2,占全球城市用地总面积的86.91%,全球前50位国家城市用地占全球城市用地面积总量的59.32%.全球城市不透水面面积为45.26×10~4km~2,集中分布于北美洲中南部、亚洲东部、欧洲大部分地区,以及全球海岸沿线地区.其中,北美洲、欧洲、亚洲城市不透水面面积占全球城市不透水面积的84.25%.研究也发现,全球不同发达程度国家之间城市不透水面分布和绿地布局呈现高度的空间差异特征,各大洲建成区内城市不透水面比例由大到小依次为:非洲>70%>南美洲>大洋洲>亚洲>60%>北美洲>欧洲>50%.全球各大洲绿地面积集中分布在北美洲东南部、欧洲西南部、亚洲东部和西部.其中,北美洲、欧洲和亚洲绿地面积占全球绿地总面积的89.44%.欧洲和北美洲的发达国家更注重城市景观设计及城市不透水面和绿地的有效镶嵌,城市建成区内绿地面积比例相对较高,而部分发展中国家和欠发达国家建成区内绿地面积比例相对较低,城市宜居环境有待提升.
五莲拆离断层带的结构、应变及运动学涡度特征

五莲拆离断层带发育于胶东半岛,作为五莲变质核杂岩的重要构造单元,分隔了作为下盘的苏鲁造山带超高压变质岩与上盘的早白垩世诸城盆地与盆地基底.断层带走向由南向北总体由NNE转为NE向,倾向W或WNW,平面上具有“波瓦状”延伸特征,主要由断层角砾岩、糜棱岩组成,向下过渡为糜棱岩化片麻岩.拆离断层带总体具有上盘向W或WNW向伸展运动.调和平均值法计算获得断层带中弗林指数K取值范围0.98~2.0,平均值约为1.35.极摩尔圆法、伸展褶劈理法、Rs/θ法、石英光轴法等多种方法获得糜棱岩、初糜棱岩的平均运动学涡度值分别为0.64~0.97、0.76~0.93、0.6~0.92、0.63~0.98,均值分别为0.83、0.80、0.78和0.86;应变测量与运动学涡度估算的结果共同说明五莲拆离断层带是在伸展拉伸条件下形成的一般型韧性剪切带.运动学轨迹显示,从NW向SE方向运动学涡度值总体存在递减的趋势,在剪切带的中上部,简单剪切作用更为明显,表现为较高的涡度值(涡度值>0.75,最大可达0.98)、低的减薄率和较低的K值;向下盘方向,纯剪切应变的成份明显增加,表现为较低的涡度值(涡度值<0.70,最小可达0.64)、相对高的减薄率和较高的K值.结合大地构造背景,五莲拆离断层带的形成与演化是华北克拉通岩石圈减薄与破坏作用在其东部边缘的一种反映.五莲断层带可以被厘定为形成于地壳伸展环境的减薄型一般剪切带,是地壳伸展引起断层带简单剪切、下盘快速抬升及岩浆上涌引起垂向施加在断层带的纯剪切联合作用的结果.
海洋对干旱半干旱区气候变化的影响

干旱半干旱区约占全球陆地总面积的41%,由于增温显著、降水稀少,导致生态脆弱、生存环境恶化,对全球气候变化的响应相对敏感.海洋作为地球气候系统的重要调节器,在干旱半干旱区气候变化过程中发挥着至关重要的作用;尤其在现代气候变化,海洋活动对干旱半干旱区气候变率的影响不可忽视.文章回顾了近百年干旱半干旱地区的气候变化特征,总结了海洋活动对其变化影响的研究进展,重点归纳了太平洋年代际振荡(PDO)、大西洋多年代际振荡(AMO)以及El Nino和La Nina等对干旱半干旱地区气候变化的影响;概述了不同海洋振荡因子协同影响干旱半干旱气候变化的机制.研究表明:全球干旱半干旱区在近百年来表现出显著的强化增温现象,呈现出明显的年代际干湿变化特征;该变化特征与海洋年代际尺度振荡因子有密切关系,由于海洋振荡因子的不同位相组合显著改变海陆热力差,进而影响西风急流、行星波及阻塞频率,导致干旱半干旱区温度及干湿特征发生改变.随着干旱半干旱地区气候变化的加剧,未来的海洋活动变化对其影响将出现新的特征,这将增加干旱半干旱地区未来气候变化的不确定性,加剧干旱半干旱区对全球气候的影响.
Study of hydraulic fracture growth behavior in heterogeneous tight sandstone formations using CT scanning and acoustic emission monitoring

Tortuous hydraulic fractures (HFs) are likely to be created in heterogeneous formations such as conglomerates, which may cause sand plugging, ultimately resulting in poor stimulation efficiency. This study aims to explore HF growth behavior in conglomerate through laboratory fracturing experiments under true tri-axial stresses combined with computed tomography scanning and acoustic emission (AE) monitoring. The effects of gravel size, horizontal differential stress, and AE focal mechanisms were examined. Especially, the injection pressure and the AE response features during HF initiation and propagation in conglomerate were analyzed. Simple HFs with narrow microfractures are created in conglomerate when the gravels are considerably smaller than the specimen, whereas complex fractures are created when the gravels are similar in size to the specimen, even under high horizontal differential stresses. Breakdown pressure and AE rates are high when a HF is initiated from the high-strength gravel. A large pressure decline after the breakdown may indicate the creation of a planar and wide HF. Analyzing the focal mechanism indicates that the shear mechanism generally dominates with an increase in the HF complexity. Tensile events are likely to occur during HF initiation and are located around the wellbore. Shear events occur mainly around the nonplanar and complex matrix/gravel interfaces.
Novel application of PEG/SDS interaction as a wettability modifier of hydrophobic carbonate surfaces

Wettability alteration of carbonate reservoirs from oil-wet to water-wet is an important method to increase the efficiency of oil recovery. Interaction between surfactants and polymers can enhance the effectiveness of surfactants in EOR applications. In this study, the interaction of polyethylene glycol (PEG) with an ionic surfactant, sodium dodecyl sulphate (SDS), is evaluated on an oil-wet carbonate rock surface by using contact angle measurements. The results reveal that wettability alteration of carbonate rocks is achieved through PEG/SDS interaction on the rock surface above a critical aggregation concentration (CAC). The behaviour of PEG/SDS aqueous solutions is evaluated using surface and interfacial tension measurements. Furthermore, the effect of PEG and SDS concentrations and impact of electrolyte addition on PEG/SDS interaction are investigated. It is shown that electrolyte (NaCl) can effectively decrease the CAC values and accordingly initiate the wettability alteration of rocks. Moreover, in a constant SDS concentration, the addition of NaCl leads to a reduction in the contact angle, which can also be obtained by increasing the aging time, temperature and pre-adsorption of PEG on the rock surface.
The petroleum system: a new classification scheme based on reservoir qualities

A new classification of petroleum systems (PSs) based on reservoir qualities is proposed. We classify PSs into the following three basic types: (1) source-rock petroleum system (SPS); (2) tight-reservoir or tight petroleum system (TPS); and (3) conventional-reservoir or conventional petroleum system (CPS). The CPS is a PS in which hydrocarbons accumulate in conventional reservoirs, and all the essential elements and processes are significant and indispensable. Oil and gas accumulations are geographically discrete and therefore exist as discontinuous accumulations. The TPS is a PS where hydrocarbons accumulate in tight reservoirs and the source rock, reservoir, seal, migration, and trap are also indispensable, but the traps are mostly non-anticlinal and the accumulations are primarily quasi-continuous and secondarily discontinuous. The SPS is a PS where both hydrocarbon generation and accumulation occurred in source rocks and traps and migration are unnecessary or inconsequential; the hydrocarbon distribution is extensive and continuous and has no distinct boundaries. The aforementioned three PSs can be derived from a common hydrocarbon source kitchen and are closely linked in terms of their formation and distribution. Therefore, to maximize the exploration efficiency, a comprehensive study and different strategies are needed by considering the SPS, TPS, and CPS as parts of a greater whole.
基于数字样机的汽车转向横拉杆优化设计

为确保汽车转向横拉杆设计的高可靠性,应用数字样机的方法,综合应用Adams/car、Abaqus等技术手段,模拟仿真汽车前行制动、转弯、冲击等九种工况,并对转向横拉杆进行多体动力学分析和静强度分析。最后应用第四强度理论,分别校核横拉杆、球头销抵抗破坏的能力。结果表明:转向横拉杆的应力分布和等效塑性分布均满足设计要求,实现了基于数字样机的汽车转向横拉杆优化设计。
基于热点应力法的液压挖掘机斗杆疲劳寿命评估

由于挖掘机的工作载荷复杂多变,易造成斗杆疲劳破坏,以某中型液压挖掘机斗杆为研究对象,采用热点应力法对斗杆进行疲劳寿命评估。通过有限元仿真结果,确定了斗杆上翼板油缸座焊趾处为危险部位,并对油缸座焊趾处进行了疲劳强度分析,发现各热点位置处的等效时间从中间到两边逐渐增大且焊趾处最外侧2个热点位置处的等效工作时间分别为8250小时和8190小时。通过斗杆疲劳台架试验可知,疲劳破坏位置与分析位置相一致,斗杆油缸座焊趾处两侧出现可见裂纹的等效工作时间为9870小时,两者时间基本一致。因此,热点应力法适用于斗杆疲劳寿命评估,且精度较高。
成人腹膜后黄色瘤超声表现1例

黄色瘤并非真正的肿瘤,是一种少见的脂代谢异常性疾病,生长缓慢,早期缺乏特异性症状。其病因及发病机制目前尚未完全清楚,多认为与脂代谢异常导致的血脂升高直接相关,因此常作为家族性高胆固醇血症较为特殊且有诊断价值的临床表现,但黄色瘤也可发生于血脂和脂蛋白正常的人群,本例患者即为此类。既往文献报道黄色瘤好发于眼睑、臀、肘、膝部、肌腱等部位,目前尚未见腹膜后黄色瘤的文献报道。本例超声表现为腹膜后巨大团块状弱回声,边界清楚,形态规则,内部回声不均匀、呈网格状,可能与其病理下泡沫细胞呈结节状分布有关。由于该位置黄色瘤罕见,超声检查经验尚需积累,临床注意与腹膜后脂肪肉瘤、纤维肉瘤等恶性肿瘤相鉴别。
眼眶黏膜相关组织淋巴瘤超声表现1例

眼附属器黏膜相关组织淋巴瘤属于结外边缘带黏膜淋巴组织增生的类型,好发于肌锥外区和眼眶前上部,多发生于45~70岁,男性多于女性,主要表现为眼球突出,眼眶包块生长,偶有结膜充血,视力减低,肿物均无表面破溃,糜烂。有文献对7例眼眶淋巴瘤的超声表现分析表明,瘤体常以低回声为主,形态不规则,边缘欠清晰,回声不均,可有分叶,并常沿肌锥外间隙向后延伸生长,肿块的后缘呈锐角而不是圆钝的,内可含条索状强回声;CDFI示多数肿瘤内血流信号丰富,收缩期峰值血流速度高,阻力指数较高,肿瘤内血流信号分布以中后部居多,血流束连续甚至呈树状。本例既往有“颈部淋巴瘤”病史,且根据其特征性图像,超声可以提示淋巴瘤的诊断,对进一步治疗提供重要线索。临床,应注意眼眶黏膜相关组织淋巴瘤与炎性假瘤、泪腺肿瘤及横纹肌肉瘤等其他眼眶疾病的鉴别诊断。
超声诊断骶尾部表皮样囊肿感染术后藏毛窦1例

骶尾部藏毛窦好发于青年男性,以慢性发病多见。该病的发病机制有先天致病学说和后天致病学说,目前学者们更倾向于后天致病学说。藏毛窦患者经手术治疗后易复发,这也在一定程度上支持了后天致病学说。本例患者超声表现为骶尾部皮下软组织层内不规则低回声区,首先考虑炎性病变,因其1年前行骶尾部表皮样囊肿手术,可能会引起毛发倒长入皮下,超声于低回声区内可见线状强回声,但本例患者有骶尾部手术史,是否为旧病复发或手术缝线遗留也应考虑,故了解藏毛窦的病因对该病的诊断具有重要意义。藏毛窦需与肛周脓肿、肛瘘和骶尾部畸胎瘤鉴别诊断,肛周脓肿、肛瘘与藏毛窦的声像图十分相似,但最主要的鉴别点是藏毛窦内部可显示线状强回声,超声医师应仔细扫查,提高诊断准确率,避免漏、误诊。
两系杂交水稻新组合越两优305

越两优305是合肥市丰乐种业股份有限公司和广东省农业科学院水稻研究所利用两系不育系广越S与恢复系广恢305配组育成的两系杂交水稻新组合,具有株型中集,丰产性好,抗稻瘟病,分蘖力、抗倒力中强,耐寒性中强(孕穗期为强,开花期为中强),食味品质较好等特点。2018年4月通过广东省农作物品种审定委员会审定。
Self-carried AIE nanoparticles for in vitro non-invasive long-term imaging

Fluorescent organic nanoparticles (NPs) based on aggregation-induced emission (AIE)-active molecules, are widely applied as non-invasive tools in bio-imaging and demonstrate great potential for studying physiological and pathological processes. In this paper, we report the synthesis of highly emissive AIEgen-based NPs (SCA NPs) via reprecipitation without any carriers as long-term cell trackers.Uniformly sized SCA NPs enjoy the advantages of high brightness, good stability, large Stokes shift, good biocompatibility, and high photostability. The SCA NPs were successfully applied for in vitro bio-imaging of HeLa cells with an excellent cancer cell uptake. In addition, a strong fluorescence from SCA NPs can still be clearly observed in HeLa cells after incubation for six generations over 15 days. Thus, the SCA NPs could be ideal fluorescent probes for non-invasive long-term cellular imaging. The AIE-active NPs display superior performance and provide a basis for the development of fluorescent organic probes for monitoring biological processes.
Surface modulated hierarchical graphene film via sulfur and phosphorus dual-doping for high performance flexible supercapacitors

Graphene surface modification by heteroatom incorporation is an attractive strategy to construct flexible electrochemical capacitors. Herein, the steam-assistant heteroatoms of sulfur and phosphorus dualdoped graphene film (s-SPG) is fabricated via an ice-template and thermal-activation approach and they demonstrate an excellent pseudocapacitive behavior in flexible electrochemical capacitors. As probed by various microscopic and spectroscopic analysis, well-maintained porosity structure is formed during the freeze-drying and steam-activation treatment; the increased surface roughness is ascribed to heteroatoms doping by the formation of S-and P-containing functional groups as electrochemical active sites. A flexible device integrated by porous s-SPG film shows high pseudocapacitive behavior with high specific capacitance (169 F/g), rate capability (91.7%) and cyclic stability (92.5%). Even at the bend angle of 120° , no obvious change of specific capacitance is found indicating a good flexibility of s-SPG devices; the current study shows that s-SPG is a very promising electrode to realize the practical applications of all solid flexible supercapacitors.
微信联合文体活动在银屑病患者延续护理中的应用

目的提高银屑病患者出院后的延续护理效果。方法将120例银屑病患者按时间顺序分为两组各60例,对照组按常规实施出院后护理;干预组开展微信联合集体文体活动的延续护理。实施6个月后评价效果。结果对照组及干预组分别有54、48例完成研究。干预后干预组社交回避与社交苦恼评分,皮肤病生活质量总分及生理、心理、穿戴、社交娱乐、工作学习5个方面评分,以及病情控制显著优于对照组(P<0.05,P<0.01)。结论对银屑病出院患者实施微信联合娱乐活动的延续护理可显著改善其心理状态和对疾病的认知,从而有效控制病情、提高生活质量。
Editorial for rare metals, special issue on biomedical metal implants

Biomedical metal materials such as titanium, magnesium and their alloys have been widely studied as orthopedic implants or cardiovascular stents due to their desirable mechanical properties and excellent biocompatibility. However, these metal implants still exist some problems in practical application including bacterial infection, lack of bioactivity, and uncontrolled corrosion behaviors. To address these problems, the performance of these metallic implants can be improved through surface modification and incorporating alloying elements into raw materials of implants.
Cell behaviors on surface of pure tantalum with nano-dimpled structure

Tantalum exhibits excellent biocompatibility and good chemical stability, which has been employed in dental and orthopedic applications. The local microenvironment of the surface of implants influence determines the surrounding cell responses. In this work, nano-dimpled structure on the surface of pure tantalum was fabricated by electrochemical anodization. The surface morphology of the nano-dimpled structure was observed, and the dimensions of the nano-dimpled structure were measured by scanning electron microscopy (SEM). The surface roughness of the sample with nano-dimpled structure was measured by atomic force microscopy (AFM). The results show that the diameter of nano-dimpled ranges from 40 to 180 nm, and the higher the applied voltage, the larger the diameter. Moreover, nano-dimpled structure has good hydrophilicity. In vitro results show that nano-dimpled structure can promote the adhesion and proliferation of mouse cranial anterior bone (MC-3T3-E1) cells. The filopodia of MC-3T3-E1 cells can be fully extended on this nano-dimpled structure. On the surface of the nano-dimpled structure with a dimple size of 40 nm, the cells have the longest aspect ratio. The small dimple size of the nanodimpled structure is beneficial to cell proliferation and osteogenic differentiation.
践行五四精神,奉献西部建设

2019年是中华人民共和国成立70周年,也是五四运动100周年。100年前,一批先进知识分子率先发起了传播新思想、新文化的爱国救亡运动,誓言“国土不可断送、人民不可低头”,奏响了恢弘雄壮的爱国主义壮歌。回顾中国青年百年奋斗史,“爱国、进步、民主、科学”的理念早已深刻融入青年的血液中。100年来,一代又一代中国青年接续奋斗,用青春之我创造青春之中国、青春之民族。李大钊同志曾寄语青年人“为世界进文明,为人类造幸福,以青年之我,创建青春之家庭,青春之国家,青春之民族,青春之人类,青春之地球,青春之宇宙,资以乐其无涯之生。”
年终盘点:2018年《NEJM》发表麻醉学领域相关研究亮点精粹

2018年《The New England Journal of Medicine》(《TNEJM》)共发表研究型论著208篇,本年度杂志沿袭一贯传统,大量篇幅集中于肿瘤新疗法,同时对传染性疾病(结核病、寨卡病毒感染、流行性感冒、艾滋病)的流行、防治与新疫苗的研发、慢性疾病(心脑血管疾病、代谢性疾病、慢性阻塞性肺疾病、儿童哮喘)的流行病学调查、对健康状况的影响等方面给予了较高关注,其中42篇论著涉及麻醉与围术期不同临床决策和治疗方案对患者预后的影响,本文精选其中16个主题21篇亮点研究以飨读者.
Distinguishing unitary gates on the IBM quantum processor

An unknown unitary gate, which is secretly chosen from several known ones, can always be distinguished perfectly. In this paper, we implement such a task on IBM's quantum processor. More precisely, we experimentally demonstrate the discrimination of two qubit unitary gates, the identity gate and the 2/3π- phase shift gate, using two discrimination schemes — the parallel scheme and the sequential scheme. We program these two schemes on the ibmqx4, a 5-qubit superconducting quantum processor via IBM cloud, with the help of the QSI modules. We report that both discrimination schemes achieve success probabilities at least 85%.
LCCFS: a lightweight distributed file system for cloud computing without journaling and metadata services

The major usage of a file system integrated with a cloud computing platform is to provide the storage for VM (virtual machine) instances. Distributed file systems, especially those implemented on top of object storage have many potential advantages over traditional local file systems for VM instance storage. In this paper, we make an investigation in the requirements imposed on a file system in cloud computing scenario, and claim that the implementation of a file system for VM instance storage could be reasonably simplified. We demonstrate that on top of an object storage with simple object-granularity transaction support, a lightweight distributed file system, which requires neither journaling nor dedicated metadata services, can be developed for cloud computing. We have implemented such a distributed file system, called LCCFS (lightweight cloud computing file system), based on the RADOS (reliable autonomic distributed object storage) object storage. Our experimental results show that for the main workloads in cloud computing, LCCFS achieves almost the same or slightly higher performance than CephFS (ceph filesystem), another published distributed file system based on RADOS. Compared to CephFS, LCCFS has only one tenth of its LOCs (lines of code). This theoretical simplicity makes it easy to implement LCCFS correctly and stably by avoiding the sheer design and implementation complexity behind CephFS, thereby making LCCFS a promising candidate in the cloud computing production environment.
Energy-efficient longitudinal driving strategy for intelligent vehicles on urban roads

Energy and environmental problems brought by automobiles are becoming more and more prominent. One promising way to solve these problems is to improve the energy efficiency of vehicles. The energy efficiency of a vehicle is not only related to vehicle performance, but also related to driving behavior. Combining longitudinal driving with intelligent transportation information can significantly improve energy efficiency [1]. Thus, energyefficient longitudinal driving strategy based on intelligent transportation information is a research hotspot for manufactures and academics.
Urban shrinkage and growth: Measurement and determinants of economic resilience in the Pearl River Delta

In the aftermath of the global financial crisis of 2008, China witnessed gradual shrinkage of cities in the Pearl River Delta (PRD). In this study, we introduce the concept of economic resilience to analyse urban growth and shrinkage in the context of a rapidly- urbanising region. Multiple regression analysis is performed to explore the determinants of economic resilience in the PRD. By measuring resistance in the shrinking phase and recoverability in the growing phase in a group of cities in the PRD, this study distinguishes four scenarios and investigates their characteristics from a spatial perspective. The results demonstrate that the financial crisis had a severe and asymmetric influence on this area, indicating more than 15 %of cities are faced with shrinking. The spatial distribution of economic resilience indicates a centre-periphery pattern, that is, high economic resilience in the inner ring and low economic resilience in the outer ring of the PRD. The service economy is found to play a significant role in promoting urban economic resilience. Results imply that sound economic policies for enhancing resilience: both poor local financial status and a high degree of export concentration adversely impact resistance, while upgrading the manufacturing economy and stimulating of industrial innovation are conducive to improve recoverability.
Evaluation of the eco-efficiency of four major urban agglomerations in coastal eastern China

Urban agglomerations in China have become the strategic core of national economic development and the main component of the new type of urbanization. However, they are threatened by a series of eco-environmental problems and challenges, including the severe overexploitation of natural resources. Eco-efficiency, which is defined as accomplishing the greatest possible economic benefit with the least possible resource input and damage to the environment, is used as an indicator to quantify the sustainability of urban agglomerations. In this work, a traditional data envelopment analysis (DEA) model with a slack-based measurement (SBM) model of undesirable outputs, was used to assess and compare the economic efficiency and eco-efficiency of four major urban agglomerations in eastern China (UAECs) in 2005, 2011, and 2014. The spatio-temporal characteristics of the evolution of urban agglomerations were analyzed. Based on the results of a slack analysis, suggestions for improving the eco-efficiency of the four UAECs are provided. The overall economic efficiency of urban agglomerations located in the Shandong Peninsula, Yangtze River Delta, and Pearl River Delta displayed a V-shaped pattern (decreased and then increased). In contrast, the overall economic efficiency of the Beijing-Tianjin-Hebei urban agglomeration declined during the study period. The Beijing-Tianjin-Hebei urban agglomeration had a considerable loss of economic efficiency due to pollution, whereas the Shandong Peninsula urban agglomeration was less impacted. Overall, the eco-environmental efficiency of the four UAECs declined from 2005 to 2011 and then increased from 2011 to 2014. In addition, the urban eco-efficiency in the four coastal UAECs was characterized by different evolution patterns. The eco-efficiency was higher in the peri-urban areas of the core cities, riverside areas, and seaside areas and lower in the inland cities. The core cities of the Beijing-Tianjin-Hebei, Yangtze River Delta, and Pearl River Delta urban agglomerations were characterized by high resource consumption, economic benefit output, and eco-efficiency. In most of cities in the urban agglomerations, the emission of pollutants declined, leading to a reduction of pollutants and mitigation of environmental problems. In addition, a differential analysis, from the perspective of urban agglomeration, was performed, and concrete suggestions for improvement are proposed.
分子印迹:热点和趋势

分子印迹是制备模拟抗体和酶的专一识别性能的重要仿生识别技术,发端于20世纪70年代初,并于90年代初展现出在仿生分子识别方面的巨大潜力而广受关注.分子印迹材料是近20年来研究非常活跃的功能材料之一,已经广泛应用于分离、样品处理和传感等领域.特别是,分子印迹技术可以和其他材料技术和纳米技术相结合,制备出各种各样的同时具有独特物理响应和靶向识别性能的先进功能材料,已经在疾病诊断、生物成像、毒物中和、药物递送及癌症靶向治疗等领域中展现出独特的优势和潜力.