An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes

Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their development.The primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid boron.In this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B system.This approach can be adopted to form various low-melting-point AM–Mg–B–O growth systems.These growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN chains.These findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs.

数字经济影响制造业结构优化的机理与实证研究

在剖析数字经济影响制造业结构优化的理论分析的基础上,从生产性服务业集聚视角切入,构建“数字经济-生产性服务业集聚-制造业结构优化”的分析框架,并使用2011~2020年制造业细分行业和各省以及城市制造业相关数据进行实证检验,以考察数字经济对制造业结构优化的影响。研究表明:数字经济能够有效推动制造业结构优化,在进行工具变量法等稳健性检验后结论仍然成立;生产性服务业集聚是数字经济影响制造业结构优化的重要机制,并且这种机制作用更多地通过高技术生产性服务业发挥的集聚效应实现;数字经济对制造业结构优化的影响存在明显的行业和区域异质性。

Correlation between TG/HDL-C Ratio and Sarcopenia in Middle-Aged and Elderly People in Southwest China

Objective: To study the correlation between TG/HDL-C ratio and sarcopenia in middle-aged and elderly people in southwest China. Methods: Body mass index (BMI) and serum of middle-aged and elderly people aged 50 - 70 years in Southwest China were collected, grip strength was measured by grip strength meter, muscle mass and fat mass of upper, lower limbs and trunk were measured by body composition analyzer based on bioelectrical impedance method, and TG and HDL-C in serum were determined by enzymatic method. Results: Pearson correlation analysis showed that TG/HDL-C ratio (r = 0.246, p p p > 0.05). Conclusion: TG/HDL-C ratio is a predictor of skeletal muscle mass, and TG/HDL-C ratio is a protective factor for sarcopenia in middle-aged and elderly people in southwest China, and it can be used as a potential evaluation indicator for sarcopenia.

Blood Calcium as a Protective Factor against Traumatic Fracture

Purpose: This study aims to investigate the predictive value of blood calcium in the prognosis of traumatic fracture. Methods: A retrospective experimental design was employed, 112 cases (52 non-fracture and 60 traumatic fracture) were randomly selected. The type of fracture complies with WHO-recommended (2019) diagnostic criteria for osteoporosis combined with fracture. The blood pressure (BP) was measured by OMRON’s HEM-7136 model electronic blood pressure monitor. Blood calcium (Ca2+), and blood phosphorus (P) values were measured using Colorimetric Roche kits on a Roche/Hitachi fully automated biochemical analyzer. Data collection and analysis followed. Results: Higher levels of age, systolic and diastolic blood pressures were found in the traumatic fracture group compared to the control group, whereas weight, height, and blood phosphorus did not differ significantly (P adjusting for age, systolic blood pressure, diastolic blood pressure, and blood phosphorus, binary logistic regression analysis revealed that blood calcium was a protective factor against traumatic fracture (β = -26.85, OR = 0.00, 95% CI = 0.00 -0.02, P = 0.022). Conclusion: The findings suggest that high and low blood calcium levels may serve as useful indicators in predicting the prognosis of fractures resulting from trauma.

高铁开通对城市群发展的非均衡影响——基于广东省样本研究

本文基于“多中心-外围”城市群理论模型,利用2005—2019年广东省21个地级市数据,考察了高铁开通对城市群发展影响的机制与效果。研究表明:高铁开通显著促进了城市群整体的经济发展,且这种影响在城市群内呈现非均衡表现;机制检验表明,高铁开通可以通过企业和人口转移对城市群资源进行重新配置;高铁对于城市群经济发展的作用受到建成时间的影响,在高铁建成的第二年中心城市产生“聚集效应”并显著促进经济发展,从第三年开始逐步转化为“辐射效应”。基于以上研究结论,本文提出如下政策建议,进一步加快广东省高速铁路建设速度,促进城市群之间互联互通;高铁建设规划要因地制宜,防止外围城市资源过度流失;同时,外围城市也应做好承接准备,充分利用中心城市的“辐射效应”。

Slippery hydrogel with desiccation-tolerant‘skin’for high-precision additive manufacturing

Hydrogels inevitably undergo dehydration,structural collapse,and shrinkage deformation due to the uninterrupted evaporation in the atmosphere,thereby losing their flexibility,slipperiness,and manufacturing precision.Here,we propose a novel bioinspired strategy to construct a spontaneously formed‘skin’on the slippery hydrogels by incorporating biological stress metabolites trehalose into the hydrogel network,which can generate robust hydrogen bonding interactions to restrain water evaporation.The contents of trehalose in hydrogel matrix can also regulate the desiccation-tolerance,mechanical properties,and lubricating performance of slippery hydrogels in a wide range.Combining vat photopolymerization three-dimensional printing and trehalose-modified slippery hydrogels enables to achieve the structural hydrogels with high resolution,shape fidelity,and sophisticated architectures,instead of structural collapse and shrinkage deformation caused by dehydration.And thus,this proposed functional hydrogel adapts to manufacture large-scale hydrogels with sophisticated architectures in a long-term process.As a proof-of-concept demonstration,a high-precision and sophisticated slippery hydrogel vascular phantom was easily fabricated to imitate guidewire intervention.Additionally,the proposed protocol is universally applicable to diverse types of hydrogel systems.This strategy opens up a versatile methodology to fabricate dry-resistant slippery hydrogel for functional structures and devices,expanding their high-precision processing and broad applications in the atmosphere.

Significant improvement after sensory tricks and trunk strength training for Parkinson’s disease with antecollis and camptocormia:A case report

BACKGROUND Patients with Parkinson's disease(PD)exhibit symptoms such as antecollis(AC)and camptocormia(CC).The pathology of these two conditions is unclear.Additionally,standard treatment methods have not been established.The article reports the case of a 65-year-old female patient with AC and CC who was treated with central and peripheral interventions to alleviate symptoms.CASE SUMMARY We present the case of a 65-year-old female PD patient with AC and CC.The course of the disease was 5 years.She was treated with rehabilitation strategies such as sensory tricks and trunk strength training.During the inpatient period,we compared and analyzed the patient's gait,rehabilitation assessment scale score,and angles of her abnormal trunk posture in the first week,the third week,and the fifth week.The patient's stride length increased,indicating that the patient's walking ability was improved.The Unified Parkinson's Disease Scale Part Three score and CC severity score decreased.Furthermore,the score of the other scale increased.In addition,the patient showed significant improvements in AC,upper CC,and lower CC angles.CONCLUSION This case study suggested that sensory tricks and trunk strength training are beneficial and safe for patients with AC and CC.

Pathfinding Pulsar Observations with the CVN Incorporating the FAST

The importance of Very Long Baseline Interferometry(VLBI)for pulsar research is becoming increasingly prominent and receiving more and more attention.We present the pathfinding pulsar observation results with the Chinese VLBI Network(CVN)incorporating the Five-hundred-meter Aperture Spherical radio Telescope(FAST).On MJD 60045(11th April 2023),PSRs B0919+06 and B1133+16 were observed with the phase-referencing mode in the L-band using four radio telescopes(FAST,TianMa,Haoping,and Nanshan)and correlated with the pulsar binning mode of the distributed FX-style software correlator in Shanghai.After further data processing with the NRAO Astronomical Image Processing System(AIPS),we detected these two pulsars and fitted their current positions with accuracy at the milliarcsecond level.By comparison,our results show significantly better agreement with predicted values based on historical VLBI observations than those with previous timing observations,as pulsar astrometry with the VLBI provides a more direct and model-independent method for accurately obtaining related parameters.

Near-infrared spectroscopy in schizophrenia:A bibliometric perspective

BACKGROUND Compared with current methods used to assess schizophrenia,near-infrared spectroscopy(NIRS)has the advantages of providing noninvasive and real-time monitoring of functional activities of the brain and providing direct and objective assessment information.AIM To explore the research field of NIRS in schizophrenia from the perspective of bibliometrics.METHODS The Web of Science Core Collection was used as the search tool,and the last search date was April 21,2024.Bibliometric indicators,such as the numbers of publications and citations,were recorded.Bibliometrix and VOS viewer were used for visualization analysis.RESULTS A total of 355 articles from 105 journals were included in the analysis.The overall trend of the number of research publications increased.Schizophrenia Research was identified as an influential journal in the field.Kasai K was one of the most influential and productive authors in this area of research.The University of Tokyo and Japan had the highest scientific output for an institution and a country,respectively.The top ten keywords were“schizophrenia”,“activation”,“near-infrared spectroscopy”,“verbal fluency task”,“cortex”,“brain,performance”,“workingmemory”,“brain activation”,and“prefrontal cortex”.CONCLUSION Our study reveals the evolution of knowledge and emerging trends in the field of NIRS in schizophrenia.the research focus is shifting from underlying disease characteristics to more in-depth studies of brain function and physiological mechanisms.

Clinical characteristics and north-south differences of inflammatory bowel disease in China: A cross-sectional study and meta-analysis

Objective:This study aimed to estimate the incidence rate and clinical characteristics of inflammatory bowel disease(IBD)in the Chinese population,specially comparing the North and South regions.Methods:We designed a questionnaire survey for patients diagnosed with IBD and conducted a systematic literature search in PubMed,China National Knowledge Internet,and Wanfang digital database,covering studies published between 2012 and 2022.Meta-analysis was performed to determine the overall incidence rate and prevalence of clinical manifestations of Crohn's disease(CD)and ulcerative colitis(UC)in China's Mainland.Clinical phenotypes and demographic characteristics were calculated with 95%confidence intervals(CI).A comparison between the northern and southern regions was also conducted.Results:The questionnaire survey included 440 patients,and 64 publications were included for Meta-analysis.The overall incidence rates of IBD,CD,and UC were 1.36(95%CI:0.79-2.33)per 100,000 person-years,0.23(95%CI:0.09-0.58)per 100,000 person-years,and 1.12(95%CI:0.69-1.80)per 100,000 person-years,respectively.The incidence rates of IBD,CD,and UC were all higher in southern China compared to the North.Clinical characteristics of 440 IBD patients from the questionnaire and 2,821 CD patients and 12,809 UC patients from the literature were analyzed.There were more male patients compared to female patients.CD cases in the North exhibited earlier disease diagnosis(P<0.01),more upper gastrointestinal lesions(P<0.01),and higher hospitalizations rates(P<0.01)compared to the South.UC cases in the North had higher severity(P<0.01),anemia rates(P<0.01),and weight loss(P<0.01)compared to the South.Conclusions:The incidence rates of IBD,CD,and UC were higher in southern China than in the North.Northern patients exhibited more severe symptoms compared to their southern counterparts.

网络关系、合作伙伴差异性对开放式创新绩效的交互影响研究

开放式创新情境下,企业跨越技术边界、组织边界,实现价值链资源整合。聚焦合作伙伴差异性(组织类型差异、技术能力差异、目标差异)、网络关系与开放式创新绩效之间的关系,利用284份有效问卷进行实证检验。研究发现:组织类型差异、技术能力差异与开放式创新绩效呈倒U型关系;目标差异对创新绩效有负向效应。另外,网络关系在合作伙伴差异性与开放式创新绩效之间起到调节作用。

Image Encryption and Decryption Based on Chaotic Algorithm

This paper analyzes the problems in image encryption and decryption based on chaos theory. This article introduces the application of the two-stage Logistic algorithm in image encryption and decryption, then by information entropy analysis it is concluded that the security of this algorithm is higher compared with the original image;And a new image encryption and decryption algorithm based on the combination of two-stage Logistic mapping and M sequence is proposed. This new algorithm is very sensitive to keys;the key space is large and its security is higher than two-stage Logistic mapping of image encryption and decryption technology.

基于演化博弈的小微平台社会责任问题协同治理研究

为解决小微平台社会责任问题治理困难现状,构建平台企业协同治理新模式。基于演化博弈理论,构建大型平台企业、小微平台企业与政府的三方博弈分析模型,通过求解与数值仿真揭示治理过程的演化均衡规律。结果表明,小微平台社会责任问题治理处于演化均衡时,共存在4种演化稳定策略组合,要使大型平台企业与小微平台形成协同共治和政府处于普通监管的均衡状态,需满足政府给予大型平台企业的税收补贴大于其参与治理的成本;小微平台在共治状态下治理的收益大于不治理的收益,并且不治理的罚款大于不治理与治理的收益差值。因此,政府应提高大型平台企业的税收补贴,适当把握小微平台企业的罚款力度,平台企业双方应致力于提高协同共治收益,以此实现互联网平台的企业社会责任协同治理,缓解小微平台企业的责任问题并解决政府监管困难现状。

三大湾区国际科技创新中心建设经验及对粤港澳大湾区的启示

以粤港澳大湾区为落脚点大力建设国际科技创新中心,是“十四五”时期我国转变经济增长模式、打造科技强国的重要抓手。本文首先系统梳理了三大湾区国际科技创新中心的发展脉络,接着从科技、教育、产业、金融等方面深入剖析了其建设经验,最后联系粤港澳大湾区国际科技创新中心建设中存在的问题,分析后得出相应的对策启示,以期为粤港澳大湾区打造国际科技创新中心提供决策参考和经验支持。

miR-1/133基因簇的进化及其调控网络

miR-1/133基因簇在心肌和骨骼肌中特异性表达,对心脏以及骨骼肌的发育及生理病理具有重要作用.该研究采用生物信息学方法,研究了miR-1/133基因簇的进化特征,预测了其靶基因及其调控的生物学过程.利用miRBase数据库对23种不同物种间miR-1/133基因簇的序列、组织方式进行了比较.采用最大似然法构建miR-1/133基因簇的系统进化树,显示该基因簇的进化与物种进化关系有一定差异.利用在线数据库对miR-1/133基因簇上游转录因子及下游靶基因进行预测,并对其进行综合分析,绘制出该基因簇的网络调控图,表明miR-1/133基因簇参与了骨骼肌与心肌发育、胰岛素受体信号通路、经典Wnt信号通路、p53信号通路等体内重要生理过程,为进一步阐明miR-1/133基因簇的生物学功能提供了理论依据.

基于ANSYS Fluent的气流喷雾干燥研究与仿真（英文）

基于气液两相流理论,采用Fluent对气流喷雾干燥的过程进行了仿真,得到了液滴通入前后的温度、速度、湿度场云图的变化情况,以及颗粒停留时间及含水量分布。结果表明:为防止粘壁现象的产生,液滴喷入塔体的速度不宜过高。为提高产品干燥效果,应适当延长干燥时间。对其喷雾干燥过程的三维数值模拟,为喷雾干燥塔的设计与制造提供了参考依据。

经济发展与纵向获得感——基于全球面板数据的分析

纵向获得感是快速现代化国家协调不平等与社会稳定关系的关键,但公众的纵向获得感如何产生,既有研究存在分歧。论文认为,除了定向的社会保护和公共服务,经济增长作为普惠性的分配机制,也是纵向获得感产生的源泉。论文首先基于一种贝叶斯方法和全球1695项调查中的229万受访者构建1980—2020年113个国家和地区的纵向获得感全球面板数据,然后利用组内-组间随机效应模型和误差修正模型考察了经济发展对于纵向获得感的组间、组内、长期和即时效应。结果表明,一国人均GDP水平与该国纵向获得感水平存在倒U形关系,人均GDP增速对于纵向获得感的正向作用具有组内、组间和即时效应,失业率的负向作用具有组内和组间效应,通胀率的负向作用具有组内效应。论文的发现表明,纵向获得感在主观层面反映经济发展的水平与速度,是解释经济发展和社会稳定关系的重要中间变量,是理解绩效合法性的新路径。

金属气凝胶:可控制备与应用展望

作为多孔材料家族的最新成员之一,金属气凝胶(Metal aerogels,MAs)是完全由纳米结构金属构筑而成的一类新型气凝胶。MAs兼有金属独特的物理化学性质与气凝胶的结构特征,同时拥有高速传质通道、高导电性三维网络、自支撑性与独特的光学特性,故在电催化、表面增强拉曼散射和生物传感等领域均表现出卓越性能。然而,MAs的研究历史较短,其可控制备、构效关系探索等研究存在众多挑战性问题,距离商业化应用尚有较长的道路。因此,系统梳理MAs的研究工作,从中汲取经验与总结设计原理是极为有益的。本文将对MAs的合成策略、应用研究进行系统评述,在此基础上对本领域的挑战与机遇进行总结展望。希望招徕更多科研工作者,共同探索MAs这一年轻而前景广阔的新材料领域。

Co-location of QTL for Sclerotinia stem rot resistance and flowering time in Brassica napus

Sclerotinia stem rot(SSR) caused by Sclerotinia sclerotiorum(Lib.) de Bary is one of the most devastating diseases of Brassica napus worldwide. Both SSR resistance and flowering time(FT) adaptation are major breeding goals in B. napus. However, early maturing rapeseed varieties, which are important for rice-rapeseed rotation in China, are often highly susceptible to SSR. Here, we found that SSR resistance was significantly negatively correlated with FT in a natural population containing 521 rapeseed inbred lines and a double haploid(DH) population with 150 individual lines, both of which had great variation in FT. Four chromosomal regions on A2, A6, C2, and C8 affecting both SSR resistance and FT were identified using quantitative trait loci(QTL) mapping after constructing a high-density genetic map based on single nucleotide polymorphism markers in the DH population.Furthermore, we aligned QTL for the two traits identified in the present and previous studies to the B. napus reference genome, and identified four colocalized QTL hotspots of SSR resistance and FT on A2(0–7.7 Mb), A3(0.8–7.5 Mb), C2(0–15.2 Mb), and C6(20.2–36.6 Mb). Our results revealed a genetic link between SSR resistance and FT in B.napus, which should facilitate the development of effective strategies in both early maturing and SSR resistance breeding and in map-based cloning of SSR resistance QTL.

A Survey of Embedding Algorithm for Virtual Network Embedding

Network virtualization(NV) is pushed forward by its proponents as a crucial attribute of next generation network, aiming at overcoming the gradual ossification of current networks, particularly to the worldwide Internet. Through virtualization, multiple customized virtual networks(VNs), requested by users, are allowed to coexist on the underlying substrate networks(SNs). In addition, the virtualization scheme contributes to sharing underlying physical resources simultaneously and seamlessly. However, multiple technical issues still stand in the way of NV successful implementation. One key technical issue is virtual network embedding(VNE), known as the resource allocation problem for NV. This paper conducts a survey of embedding algorithms for VNE problem. At first, the NV business model for VNE problem is presented. Then, the latest VNE problem description is presented. Main performance metrics for evaluating embedding algorithms are also involved. Afterwards, existing VNE algorithms are detailed, according to the novel proposed category approach. Next, key future research aspects of embedding algorithms are listed out. Finally, the paper is briefly concluded.