栓皮栎叶片解剖结构种群变异及其对环境因子的适应

【目的】厘清天然广布树种栓皮栎叶片解剖结构的种群变异及其与环境因子的关系。【方法】以中国28个天然分布栓皮栎种群叶片为研究对象,用常规石蜡切片结合光学显微技术对栓皮栎叶片解剖性状进行研究,用巢式方差分析、Pearson相关性分析等方法对栓皮栎叶片解剖结构的种群变异与环境因子关系进行分析。【结果】(1)栓皮栎叶片解剖性状在28个种群间存在显著差异,平均变异系数为7.84%~15.16%,且同一叶片解剖性状在不同种群间的变异范围不同;(2)9个解剖性状在种群内及种群间均存在极显著差异,平均表型分化系数为37.44%,解剖性状变异主要来自种群内;(3)叶片厚度、上表皮厚度、栅栏组织厚度、海绵组织厚度与纬度呈显著正相关关系,年均气温及年降水量对上表皮厚度和栅栏组织厚度有显著影响。【结论】栓皮栎具有丰富的遗传多样性,为适应低温与干旱,栓皮栎叶片整体呈增厚趋势。研究结果为了解栓皮栎环境适应策略提供理论依据。

Combining Deep Learning with Knowledge Graph for Design Knowledge Acquisition in Conceptual Product Design

The acquisition of valuable design knowledge from massive fragmentary data is challenging for designers in conceptual product design.This study proposes a novel method for acquiring design knowledge by combining deep learning with knowledge graph.Specifically,the design knowledge acquisition method utilises the knowledge extraction model to extract design-related entities and relations from fragmentary data,and further constructs the knowledge graph to support design knowledge acquisition for conceptual product design.Moreover,the knowledge extraction model introduces ALBERT to solve memory limitation and communication overhead in the entity extraction module,and uses multi-granularity information to overcome segmentation errors and polysemy ambiguity in the relation extraction module.Experimental comparison verified the effectiveness and accuracy of the proposed knowledge extraction model.The case study demonstrated the feasibility of the knowledge graph construction with real fragmentary porcelain data and showed the capability to provide designers with interconnected and visualised design knowledge.

肺癌疫苗研究进展

随着医学技术的发展,肿瘤疫苗作为一种新型精准免疫治疗手段在临床应用中逐渐受到重视。在全球新型冠状病毒(corona virus disease 2019,COVID-19)疫情爆发的背景下,疫苗技术的研发得到了进一步的发展。根据其抗原种类的不同,肿瘤疫苗可分为全细胞疫苗、多肽疫苗、信使核糖核酸(messenger ribonucleic acid,mRNA)疫苗、重组病毒疫苗等。尽管已经有一些肿瘤疫苗上市并取得了一定疗效,但过去一段时间肿瘤疫苗在临床试验中的结果仍不尽如人意,随着第二代测序技术(next-generation sequencing,NGS)的成熟和生物信息学的不断发展,使得肿瘤亚群发展的全过程动态跟踪成为了现实,为个性化定制以新抗原为核心的治疗性肿瘤疫苗打下了坚实的基础。本文回顾了近年来不同种类肿瘤疫苗的发展情况,以肺癌举例总结了肿瘤疫苗在临床应用中的发展成果,并对未来以新抗原为核心的肿瘤疫苗开发进行了展望。

Hydrogen sulfide protects against amyloid beta-peptide induced neuronal injury via attenuating inflammatory responses in a rat model

Neuroinflammation has been recognized to play a critical role in the pathogenesis of Alzheimer's disease (AD), which is pathologically characterized by the accumulation of senile plaques containing activated microglia and amyloid β-peptides (Aβ). In the present study, we examined the neuroprotective effects of hydrogen sulfide (H2S) on neuroinflammation in rats with Aβ1-40 hippocampal injection. We found that Aβ-induced rats exhibited a disorder of pyramidal cell layer arrangement, and a decrease of mean pyramidal cell number in the CA1 hippocampal region compared with those in sham operated rats. NaHS (a donor of H2S, 5.6 mg/kg/d, i.p.) treatment for 3 weeks rescued neuronal cell death significantly. Moreover, we found that H2S dramatically suppressed the release of TNF-α, IL-1β and IL-6 in the hippocampus. Consistently, both immunohistochemistry and Western blotting assays showed that H2S inhibited the upregulation of COX-2 and the activation of NF-κB in the hippocampus. In conclusion, our data indicate that H2S suppresses neuroinflammation via inhibition of the NF-κB activation pathway in the Aβ-induced rat model and has potential value for AD therapy.

Hierarchical sulfur and nitrogen co-doped carbon nanocages as efficient bifunctional oxygen electrocatalysts for rechargeable Zn-air battery

Exploring inexpensive and efficient bifunctional electrocatalysts for oxygen reduction reaction(ORR) and oxygen evolution reaction(OER) is critical for rechargeable metal-air batteries. Herein, we report a new 3D hierarchical sulfur and nitrogen co-doped carbon nanocages(hSNCNC) as a promising bifunctional oxygen electrocatalyst by an in-situ MgO template method with pyridine and thiophene as the mixed precursor. The as-prepared h SNCNC exhibits a positive half-wave potential of 0.792 V(vs. reversible hydrogen electrode, RHE) for ORR, and a low operating potential of 1.640 V at a 10 mA cm-2 current density for OER. The reversible oxygen electrode index is 0.847 V, far superior to commercial Pt/C and IrO2,which reaches the top level of the reported bifunctional catalysts. Consequently, the hSNCNC as air cathodes in an assembled Zn-air battery features low charge/discharge overpotential and long lifetime. The remarkable properties arises from the introduced multiple heteroatom dopants and stable 3D hierarchical structure with multi-scale pores, which provides the abundant uniform high-active S and N species and efficient charge transfer as well as mass transportation. These results demonstrate the potential strategy in developing suitable carbon-based bi-/multi-functional catalysts to enable the next generation of the rechargeable metal-air batteries.

Ascorbic acid synthesis and transportation capacity in old laying hens and the effects of dietary supplementation with ascorbic acid

Background: Laying hens over 75 weeks of age commonly show great declines in immunity and production performance.It is unclear whether these declines can be relieved by supplementing with ascorbic acid(AA) in feed.Two trials were conducted to investigate the synthesis and metabolism of AA in layers of different ages and the effects of dietary supplemental AA on the performance and the immune and antioxidant statuses of 78 weeks old hens.Methods: In Exp.1,equal numbers(24 hens) of 35 weeks old(Young) and 75 weeks old(Old) layers were fed the same diet without AA supplementation for 4 weeks.In Exp.2,360 healthy 78 weeks old laying hens were randomly assigned to 4 treatments(basal diet supplemented with 0,0.25,0.5,or 1 g AA/kg diet) in an 8-week feeding trial.Results: The old hens tended to have decreased L-gulonolactone oxidase(GLO) synthase activity in the kidney and liver than that of the young hens(P = 0.07 and P = 0.05,respectively).Compared with the young hens,the old hens had lower hepatic antioxidant capacity allowing for the lower thioredoxin(TXN),thioredoxin reductase(TXNR) and cytochrome b5 reductase(CYB5 R) gene expression(P < 0.05),whereas increased sodium-dependent vitamin C transporter(SVCT) 1 expression levels in the ileum and kidney and enhanced splenic and hepatic AA concentrations(P < 0.05).Dietary supplementation with AA significantly decreased GLO enzyme activity but increased splenic AA concentration and anti-bovine serum albumin IgG levels(P < 0.05) and tended to increase CD4+T lymphocyte numbers(P = 0.06) in serum.Supplementation of 0.25 g AA/kg diet significantly increased hepatic total antioxidant capacity(T-AOC,P < 0.05) relative to the control group.Conclusions: Laying hens could synthesize AA in both the kidney and the liver,though the GLO enzyme activities were 100 times greater in kidneys than in livers.The old laying hens had greater absorption and reabsorption capacity and higher AA retention in some tissues that did the young hens.Dietary supplementation of AA can improve the health of old layers by enhancing immunity and antioxidant capacity.

In vivo and in vitro protective effect of arginine against intestinal inflammatory response induced by Clostridium perfringens in broiler chickens

Background:Necrotic enteritis is a widespread disease in poultry caused by Clostridium perfringens.We previously reported that dietary arginine supplementation protected the intestinal mucosa of broiler chickens with necrotic enteritis,but the related protective mechanisms remain unclear.The in vivo trial was designed as a 2×2 factorial arrangement to evaluated the effects of arginine supplementation on inflammatory responses,arginine transporters,arginine catabolism and JAK-STAT signalling pathway in broiler chickens challenged with C.perfringens or without C.perfringens.Furthermore,we validated the in vivo results using intestinal epithelial cells of chicken embryos.Results:C.perfringens infection markedly increased gut gross pathological and histopathological lesion scores,promoted liver C.perfringens invasion,reduced serum arginine levels,and elevated jejunal mucosal lysozyme activities(P<0.05),but these effects were significantly reversed by arginine supplementation in vivo(P<0.05).The challenge significantly increased serum procalcitonin levels,jejunal mucosal iNOS activities and jejunal IL-6,TGF-β3,cationic amino acid transporter(CAT)-1,and CAT-3 mRNA expression(P<0.05),whereas arginine supplementation significantly reduced jejunal IFN-γ,IL-1β,IL-6,IL-10,TGF-β3,and CAT-3 mRNA expression(P<0.05).Arginine supplementation significantly attenuated the C.perfringens challenge-induced increases in jejunal i NOS,arginase 2,arginine decarboxylase,arginine:glycine amidinotransferase,JAK1,JAK3,STAT1,and STAT6 mRNA expression(P<0.05).The in vitro experiment showed that C.perfringens challenge markedly increased cellular cytotoxicity and the mRNA expression of IL-1β,IL-8,IL-10,CAT-1 and CAT-3(P<0.05),which were significantly reversed by 50μmol/L and/or400μmol/L arginine pre-treatment(P<0.05).Conclusions:Arginine prevented C.perfringens challenge-induced circulated arginine deficiency,normalized intestinal arginine transport and catabolism,down-regulated JAK-STAT signalling pathway and attenuated the inflammatory response,which exerted protective effects on the intestine of broiler chickens.

MC尼龙链增长与聚集态形成过程相互作用对其性能的影响

通过采用双官能团助催化剂、三官能团助催化剂及延长三官能团体系保压时间3种工艺,制备了浇铸尼龙(MC尼龙)样品2-FC-MC、3-FC-MC和3-FC-T-MC尼龙。利用差示扫描量热分析和偏光显微镜对样品聚集态结构进行了表征,并对其力学性能、耐热性能和吸水性能进行了测试,研究了MC尼龙链增长与其聚集态形成过程中相互作用对其性能的影响。结果表明,2-FC工艺制备的MC尼龙晶体结构完整且致密,同时存在α晶和γ晶,但相分离明显,材料呈脆性;3-FC工艺聚合过程中MC尼龙链增长速率较快,但链段有效堆叠效率较低,样品的晶体结构不完整,相分离程度较低,冲击性能较好,但热稳定性较差,且易吸水;3-FC-T-MC尼龙的链段有效堆叠程度明显提高,存在结构较完善的晶体,且相界面不明显,综合性能较高。

Effects of age on immune function in broiler chickens

Background:There are many diseases in poultry,many of which are caused by poor immune function.It is not clear how cytokines and various immune cell functions change with age in modern broilers.The purpose of this study was to explore the patterns of development of the immunity of the broiler chickens in cage.Results:The results showed that there were 3 development patterns of immunity in the broiler chickens.The first pattern was Down-Up.Cytokines and some immune indicators first decreased and then increased,and the lowest levels of immunity basically occurred from d 6 to 13.The second pattern was Up-Down,and from d 30 to 34,the highest levels of non-specific cellular immunity components,such as the peripheral blood mononuclear macrophage ratio,specific cellular immunity components,such as the peripheral blood helper T(Th)cell ratio and T cell and B cell proliferation activity,and mucosal immunity components,such as the ileal CD4,TGF-β1 and IgA mRNA levels,were observed.The third pattern was Up-Up,and the levels of the non-specific cellular immunity components,such as the serum nitric oxide(NO),C3 and C4 levels,the specific cellular immunity components,such as the spleen index,peripheral blood IL-2,IFN-γ/IL-4,cytotoxic T(Tc)cell ratio,and splenic NF-κB mRNA levels,the humoral immunity components,such as the serum IgG level,the mucosal immunity components,such as the ileal MHC-II,CD3d,TCRβsubunit,TCRζsubunit,IFN-γ,pIgR mRNA and ileal mucosa sIgA levels,were continuing to increase from d 1 to 34.Conclusions:It could be concluded that the immune system and its function have not developed well in the broiler chickens d 6 to 13 and that the immune system does not mature until d 30 to 34 in the broiler chickens in cages.It is necessary to enhance the immune function of the broiler chickens through nutritional measures from d 1 to 30.

A sulfotransferase gene BnSOT-like1 has a minor genetic effect on seed glucosinolate content in Brassica napus

The theory and associated selection methods of classical quantitative genetics are based on the multifactorial or polygene hypothesis.Major genes or quantitative trait loci(QTL)in modern quantitative genetics based on a“major gene plus polygenes”genetic system have been paid much attention in genetic studies.However,it remains unclear how the numerous minor genes act,although the polygene theory has sustained genetic improvement in plants and animals for more than a hundred years.In the present study,we identified a novel minor gene,BnSOT-like1(BnaA09g53490D),which is a sulfotransferase(SOT)gene catalyzing the formation of the core glucosinolate(GSL)structure in Brassica napus.This gene has been occasionally found during investigations of plant height-related genes,but has not been identified by QTL mapping because of its small phenotypic effects on GSL content.The overexpression of BnSOT-like1 up-regulated the expression of aliphatic GSL-associated genes,leading to a high seed aliphatic GSL content,and the overexpression of the allelic gene Bnsot-like1 did not increase seed GSL content.These findings suggest that the SOT gene has a marked effect on a quantitative trait from a reverse genetics standpoint,but a minor effect on the quantitative trait in its natural biological state.Because of the redundancy of GSL biosynthetic genes in the allotetraploid species B.napus,mutations of a single functional gene in the pathway will not result in significant phenotypic changes,and that the genes in biosynthetic pathways such as BnSOT-like1 in our study have minor effects and may be called polygenes in contrast to the reported three regulatory genes(BnHAG1s)which strongly affect GSL content in B.napus.The present study has shed light on a minor gene for a quantitative trait.

披文以入情——《文心雕龙》“六观”说

"六观"说是刘勰在《知音》篇中提出的重要的文学批评与鉴赏方法,他针对人们对文章不能作出正确评价发出了"知音其难哉"的感慨。对于"文情难鉴"的问题,刘勰提出了"披文以入情","六观"说由此而来。考察以往对"六观"说的研究,多在"知音"说的巨大光环下隐而不全,常以约略处之。具体而言,"六观"说指:位体、置辞、通变、奇正、事义、宫商。它不仅是一种文学批评与鉴赏的方法,更是中国古代诗学阐释学的重要命题。探究刘勰"六观"说的具体内容,对当今的文学批评、鉴赏,以及诗学阐释学的研究具有一定借鉴意义。

A New Descent Nonlinear Conjugate Gradient Method for Unconstrained Optimization

In this paper, a new nonlinear conjugate gradient method is proposed for large-scale unconstrained optimization. The sufficient descent property holds without any line searches. We use some steplength technique which ensures the Zoutendijk condition to be held, this method is proved to be globally convergent. Finally, we improve it, and do further analysis.

Three New Hybrid Conjugate Gradient Methods for Optimization

In this paper, three new hybrid nonlinear conjugate gradient methods are presented, which produce suf?cient descent search direction at every iteration. This property is independent of any line search or the convexity of the objective function used. Under suitable conditions, we prove that the proposed methods converge globally for general nonconvex functions. The numerical results show that all these three new hybrid methods are efficient for the given test problems.

Using schema transforation pathways for biological data integration

In web environments, proteomics data integra-tionin the life sciences needs to handle the problem of data conflicts arising from the het-erogeneity of data resources and from incom-patibilities between the inputs and outputs of services used in the analysis of the resources. The integration of complex, fast changing bio-logical data repositories can be potentially sup-ported by Grid computing to enable distributed data analysis. This paper presents an approach addressing the data conflict problems of pro-teomics data integration. We describe a pro-posed proteomics data integration architecture, in which a heterogeneous data integration sys-tem interoperates with Web Services and query processing tools for the virtual and materialised integration of a number of proteomics resources, either locally or remotely. Finally, we discuss how the architecture can be further used for supporting data maintenance and analysis ac-tivities.

一种图像回归与关联关系特征融合的遥感影像变化检测方法

异质遥感影像变化检测是一个重要且具有挑战性的研究课题。针对直接比较异质数据进行变化检测导致检测精度低的问题,提出了一种图像回归与关联关系特征融合(Image Regression and Association-based Feature, IRAF)的异质遥感影像变化检测方法。首先基于信息熵理论量化异质数据的信息量差异并确定回归方向,采用多输出多层感知器图像回归得到与原始影像特征空间分布相近的回归图像;其次,得到差异图像并基于模糊局部信息C均值(Fuzzy Local Information C-Means,FLICM)算法找到部分显著样本对用于后续检测。为了考虑不同特征间的关联关系并充分利用数据中潜在的高阶信息,采用基于关联关系特征的融合算法(Association-based Fusion,AF)对原始遥感数据进行增强,最后利用融合后的特征训练分类模型得到最终的变化二值图。为验证该方法的有效性,采用Sardinia、Yellow River和Texas这3组真实数据集进行实验,Ka分别达到了0.796 1、0.827 1、0.958 1。与相关方法进行对比的实验结果表明该方法在不同数据集上均得到了最优的检测结果,能够抑制噪声的影响且有效提升变化检测精度。

FACTORS INFLUENCING FOOD-WASTE BEHAVIORS AT UNIVERSITY CANTEENS IN BEIJING,CHINA:AN INVESTIGATION BASED ON THE THEORY OF PLANNED BEHAVIOR

Food waste is a major social problem that contributes to the overutilization of natural resources,affecting economic progress and environmental protection.Food waste occurs throughout the whole process of the food supply chain,especially during the consumption stage.As a special group of consumers,the emerging adults at university may have unique food consumption patterns and their food waste behavior in university canteens deserves more attention.To understand the influential factors of the food-waste behavior of students in university canteens,a field survey was conducted at China Agricultural University canteen with 705 respondents.Based on the theory of planned behavior,this paper examines the influencing factors of student food-waste behavior from three dimensions:sociopsychological factors,individual characteristics and dining factors.The results indicate that the percentage of students who waste food is relatively low,at roughly 27%.Perceived behavior control,gender,monthly living expenses,BMI,mealtime,meal expectations and food portion were significantly correlated with student food-waste behavior,among which perceived behavior control had the most prominent correlation,followed by food portion.Behavioral intention,household location and palatability were not significantly correlated with student food-waste behavior.Therefore,it is necessary to promote publicity and education on reducing food waste on campus,reinforce the administration of the department of support service,and optimize the food portion in the canteen.

气溶胶对降水影响的现象和机制

Aerosols greatly influence precipitation characteristics,thereby impacting the regional climate and human life.As an indispensable factor for cloud formation and a critical radiation budget regulator,aerosols can affect precipitation intensity,frequency,geographical distribution,area,and time.However,discrepancies exist among current studies due to aerosol properties,precipitation types,the vertical location of aerosols and meteorological conditions.The development of technology has driven advances in current research,but understanding the aerosol effects on precipitation remain complex and challenging.This paper revolves around the following topics from the two perspectives of Aerosol-Radiation Interaction(ARI)and Aerosol-Cloud Interaction(ACI):(1)the influence of different vertical locations of absorbing/scattering aerosols on the atmospheric thermal structure;(2)the fundamental theories of ARI reducing surface wind speed,redistributing water vapour and energy,and then modulating precipitation intensity;(3)different aerosol types(absorbing versus scattering)and aerosol concentrations causing different precipitation diurnal and weekly variations;(4)microphysical processes(cloud water competition,invigoration effect,and evaporation cooling)and observational evidence of different effects of aerosols on precipitation intensity,including enhancing,inhibiting,and transitional effects from enhancement to suppression;and(5)how meteorology,water vapor and dynamics influencing the effect of ACI and ARI on precipitation.In addition,this review lists the existing issues and future research directions for attaining a more comprehensive understanding of aerosol effects on precipitation.Overall,this review advances our understanding of aerosol effects on precipitation and could guide the improvement of weather and climate models to predict complex aerosol-precipitation interactions more accurately.

关于牙裂综合征的病因和早期诊断的研究进展

牙裂综合征是一种常见的疾病,本文综述了包括牙齿结构不良、异常力和医源性因素等潜在牙裂综合征的病因,以及临床症状、视觉增强、X线、光学成像和其他新技术在牙裂综合征早期诊断的研究进展,以期为牙裂综合征的预防和诊治提供一定的指导意义。

A Brief Review of Short Tandem Repeat Mutation

Short tandem repeats (STRs) are short tandemly repeated DNA sequences that involve a repetitive unit of 1–6 bp. Because of their polymorphisms and high muta- tion rates, STRs are widely used in biological research. Strand-slippage replication is the predominant mutation mechanism of STRs, and the stepwise mutation model is regarded as the main mutation model. STR mutation rates can be influenced by many factors. Moreover, some trinucleotide repeats are associated with human neurodegenerative diseases. In order to deepen our knowledge of these diseases and broaden STR application, it is essential to understand the STR mutation pro- cess in detail. In this review, we focus on the current known information about STR mutation.

Boosting oxygen reduction activity of spinel CoFe2O4 by strong interaction with hierarchical nitrogen-doped carbon nanocages

The unique hierarchical nitrogen-doped carbon nanocages(h NCNC) are used as a new support to homogeneously immobilize spinel Co Fe_2O_4 nanoparticles by a facile solvothermal method. The so-constructed hierarchical Co Fe_2O_4/h NCNC catalyst exhibits a high oxygen reduction activity with an onset potential of0.966 V and half-wave potential of 0.819 V versus reversible hydrogen electrode, far superior to the corresponding 0.846 and 0.742 V for its counterpart of Co Fe_2O_4/h CNC with undoped hierarchical carbon nanocages(h CNC) as the support, which locates at the top level for spinel-based catalysts to date.Consequently, the Co Fe_2O_4/h NCNC displays the superior performance to the Co Fe_2O_4/h CNC, when used as the cathode catalysts in the home-made Al-air batteries. X-ray photoelectron spectroscopy characterizations reveal the more charge transfer from Co Fe_2O_4 to h NCNC than to h CNC, indicating the stronger interaction between Co Fe_2O_4 and h NCNC due to the nitrogen participation. The enhanced interaction and hierarchical morphology favor the high dispersion and modification of electronic states for the active species as well as the mass transport during the oxygen reduction process, which plays a significant role in boosting the electrocatalytic performances. In addition, we noticed the high sensitivity of O 1 s spectrum to the particle size and chemical environment for spinel oxides, which is used as an indicator to understand the evolution of ORR activities for all the Co Fe_2O_4-related contrast catalysts. Accordingly,the well-defined structure-performance relationship is demonstrated by the combination of experimental characterizations with theoretical calculations. This study provides a promising strategy to develop efficient, inexpensive and durable oxygen reduction electrocatalysts by tuning the interaction between spinel metal oxides and the carbon-based supports.