浅谈铝合金结构件焊接变形的控制

铝合金由于热膨胀系数较大,导致焊接变形严重。因此,为了减少焊接变形,研究对6061-T6铝合金的焊接变形情况进行了分析,并进一步研究了施加控制措施后的铝合金薄板变形情况。实验结果显示,进行电子束叠焊时,铝合金薄板中心区域的变形量最大,且实测变形量始终小于仿真变形量。这是因为实验时对薄板使用了夹具夹持,而在施加反变形或刚性约束后,薄板的变形量明显较少,且与原变形方向相反。上述结果表明,通过反变形法或刚性约束法能有效减少铝合金的焊接变形量,且刚性约束法的控制效果更好。

中国农村生育转变的类型与宗族文化的区域差异

本文根据1970年代以来总和生育率下降与出生性别比失衡在不同区域的组合,将中国农村生育转变归纳为“阻滞—失衡”型生育转变和“平滑—均衡”型生育转变等两种类型。生育转变类型与宗族文化的区域差异有关,不同区域村庄社区内部宗族社会网络与宗族规范因为历史原因而存在差异,这两个因素交织在一起,使得中国农村生育转变存在十分有趣的空间分布:在华南以及中原等文化区,在宗族文化及其社会结构的作用下,生育率下降相对滞后,同时出现严重出生性别比失衡;而在村庄历史比较短暂、宗族文化薄弱的东北、西南、长江流域的大部分地区,率先达到较低的生育水平,出生性别比大致保持平衡。

MicroRNA-21 targets tumor suppressor genes in invasion and metastasis

MicroRNAs (miRNAs ) 是在 post-transcriptional 指向编码蛋白质的 mRNAs 的小非编码的 RNA 铺平的自然地发生的一个班。我们的以前的研究建议 mir-21 作为 oncogene 工作并且在 tumorigenesis 有一个角色，部分地通过肿瘤的规定压制或基因对流肌浆球蛋白 1 (TPM1 ) 。给那 TPM1 在房间移植被含有，在我们进一步调查了的这研究在房间侵略和肿瘤转移的 mir-21 的角色。我们发现在变形乳癌 MDA-MB-231 房间的 mir-21 的抑制显著地减少了侵略和肺转移。与这一致， TPM1 的宫外的表示显著地减少了房间侵略。而且，我们识别了二个另外的直接 mir-21 目标，规划房间死亡 4 (PDCD4 ) 并且妈大头针，哪个在侵略和转移被含有。象 TPM1 一样， PDCD4 和妈大头针也减少了 MDA-MB-231 房间的侵略海角。最后， PDCD4 的表示和妈大头针相反地在人的胸肿瘤标本与 mir-21 表示相关，显示由在这些肿瘤的 mir-21 的 PDCD4 和妈大头针的潜在的规定。总起来说，结果建议作为 oncogenic miRNA， mir-21 由指向多重肿瘤 / 转移不仅在肿瘤生长而且在侵略和肿瘤转移有一个角色压制或基因。因此， mir-21 的抑制可以为先进癌症的治疗提供一条新奇途径。

Effects of MIF on proliferation,migration,and STAT1 pathway of colon cancer cells

Objective This study aimed to investigate how macrophage migration inhibitory factor(MIF)regulates the interaction of signal transducer and activator of transcription 1(STAT1)with CD74,and affects colon cancer proliferation and invasion.Methods After transfecting MIF small interfering RNA into the SW480 cell line,the expression of STAT1 and CD74 mRNA was detected by qRT-PCR and western blotting.Transwell and MTT assays were performed to detect the colon cancer cell invasion and proliferation ability.Co-immunoprecipitation was used to detect the interaction between CD74 and STAT1 proteins in the treated and control groups.Results The cellular biological assays(MTT and Transwell)showed that the proliferation and invasion ability of colon cancer cells decreased after MIF knockdown;the results showed significant statistical difference(P<0.05).The results of the co-immunoprecipitation assay suggested that MIF knockdown in colon cancer cells could inhibit the binding of CD74 and STAT1 proteins;statistical difference was observed between the two groups(P<0.05).Conclusion MIF can increase the proliferation and invasion of colon cancer cells by promoting the combination of CD74 and STAT1.

Evapotranspiration estimation of Platycladus orientalis in Northern China based on various models

Platycladus orientalis is one of the most popular afforestation species and greening species for water management in arid and semi-arid regions of northern China. We applied various models to estimate and validate artificial P. orientalis forest evapotranspiration features with the goal of accurately estimating the water use of a P.orientalis plantation. The American Society of Civil Engineers Evapotranspiration–Penman–Monteith model（APM） and FAO56–Penman–Monteith model（FPM） are extensively applied for vegetation evapotranspiration estimation because their reliability has been validated by many scholars. The Priestley–Taylor model（PT） and Hargreaves model（HS） require only the daily maximum temperature,daily minimum temperature and solar radiation to estimate evapotranspiration and are thus widely applied to grasslands but not to forests. We used the Energy Balance Bowen Ratio（EBBR） system to validate the accuracy of the four models. The results indicated that：（1） Compared to the EBBR measurement annual value, APM was the most accurate, followed by FPM, and PT;（2） During the year, the accuracies of the four models varied. APM and FPM underestimated evapotranspiration during June, July and August, whereas PT and HS overestimated evapotranspiration during this period. In the rest of the year, the estimation accuracies were reversed;（3） An analysis of the possible reasons indicated that wind speed, air temperature and precipitation were the most important contributors.High temperatures were measured in June, July and August, which led to an overestimation by PT and HS because these two models only calculated the temperature and radiation without vegetation information. Underestimation also occurred when a low temperature was recorded. Though APM and FPM addressed both meteorological and vegetation factors, slight deviations still existed; and（4） The two models were modified based on EBBR-measured data. Relative humidity was introduced into PT, and parameter ‘‘A’’ in the HS estimation model was amended to1.41. The accuracy of the modified models significantly increased. The study highlighted the application, comparison and improvement of four models in estimating evapotranspiration and offers more approaches to assess forest hydrological functions.

Metabolism regulation of TD26 in hepatocellular carcinoma: mechanistic links and potential clinical implication

Objective:Hepatocellular carcinoma(HCC)is a leading cause of cancer-related deaths worldwide,and HCC cells metabolically distinct from normal hepatocytes.Increased lipogenesis has been reported to play a critical role in HCC progression.This study aims to investigate the underlying mechanism contributing to lipogenesis increase in HCC.

Analysis of Factors Influencing Forest Farmers' Enthusiasm for Forest Culture and Management after the Completion of Reform of Collective Forest Right System

Taking Jiangshan City in Zhejiang Province for example,this article uses the binary logit choice model based on the field survey data,to study the factors influencing forest farmers'enthusiasm for forest culture and management after the completion of reform of collective forest right.Finally the following recommendations are put forth:further improving and implementing the forest ecological benefit compensation fund system;reforming the felling management mode and gradually establishing the sustainable forest management system based on forest management plan;improving the technology,market and information services to strengthen the forestry science and technology support;developing the specialty industries such as the bamboo industry and oil-tea camellia industry;developing the under-forest economy and cultivating the underforest industries with characteristics based on the local circumstances.

皖南地区非飞行小型兽类多样性调查及编目

皖南地区是安徽省动物资源最丰富的区域,也是华东地区生物多样性热点研究区域,但目前该区域小型兽类多样性研究相对滞后,物种本底数据仍不清楚。本研究于2018年5月至2019年12月利用夹日法和陷阱法对皖南地区14个区域的小型兽类进行了调查,结合传统形态鉴定方法和DNA条形码技术(Cyt b和COI基因)对标本进行鉴定。同时,结合历史资料对皖南小型兽类名录进行了整理。此次调查共采集小型兽类标本647号,隶属3目8科17属23种,其中啮齿目13种,劳亚食虫目9种,兔形目1种。分子分析结果显示皖南地区的川西缺齿鼩(Chodsigoa hypsibia)、华南缺齿鼹(Megera latouchei)、青毛巨鼠(Berylmys bowersi)、赤腹松鼠(Callosciurus erythraeus)和侯氏猬(Mesechinus hughi)与其他地区的样本存在较为明显的分化。结合历史资料,皖南地区共有小型兽类3目9科24属34种,其中啮齿目23种,劳亚食虫目10种,兔形目1种。皖南地区小型兽类资源十分丰富,对于华东地区生物多样性保护非常重要,但其多样性仍可能被低估,该地区小型兽类资源还有待进一步深入调查。

CCL5 deficiency promotes liver repair by improving inflammation resolution and liver regeneration through M2 macrophage polarization

Despite the diverse etiologies of drug-induced liver injury(DILI),innate immunity activation is a common feature involved in DILI progression.However,the involvement of innate immunity regulation in inflammation resolution and liver regeneration in DILI remains obscure.Herein,we identified the chemokine CCL5 as a central mediator of innate immunity regulation in the pathogenesis of DILI.First,we showed that serum and hepatic CCL5 levels are elevated in both DILI patients and an APAP-induced liver injury(AILI)mouse model.Interestingly,both nonparenchymal cells and stressed hepatocytes are cell sources of CCL5 induction in response to liver injury.Functional experiments showed that CCL5 deficiency has no effect on the early phase of AILI but promotes liver repair in the late phase mainly by promoting inflammation resolution and liver regeneration,which are associated with an increased number of hepatic M2 macrophages.Mechanistically,CCL5 can directly activate M1 polarization and impede M2 polarization through the CCR1-and CCR5-mediated activation of the MAPK and NF-κB pathways.We then showed that CCL5 inhibition mediated by either a CCL5-neutralizing antibody or the antagonist Met-CCL5 can greatly alleviate liver injury and improve survival in an AILI mouse model.Our data demonstrate CCL5 induction during DILI,identify CCL5 as a novel innate immunity regulator in macrophage polarization,and suggest that CCL5 blockage is a promising therapeutic strategy for the treatment of DILI.

Removal of PCDD/Fs and PCBs from flue gas using a pilot gas cleaning system

A 100 Nm3 /hr capacity pilot scale dual bag filter （DBF） system was tested on the flue gas from an actual hazardous waste incinerator （HWI）, the removal efficiency of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans （PCDD/Fs） and polychlorinated biphenyls （PCBs） was also studied. The first filter collected most of the fly ash and associated chlorinated organic; then activated carbon （AC） was injected and used to collect phase chlorinated organic from the gas. Concentrations of PCDD/Fs and PCBs after the DBF system were 0.07 and 0.01 ng TEQ/Nm3 , respectively, which were both far below the national emission standard. Comparing with the original single bag filter system, the PCDD/Fs concentration dropped a lot from 0.36 to 0.07 ng TEQ/Nm3 . Increasing AC feeding rate enhanced their collection efficiency, yet reduced the AC utilization efficiency, and it still needs further study to select an appropriate feeding rate in the system. These results will be useful for industrial application and assist in controlling emissions of PCDD/Fs and other persistent organic pollutions from stationary sources in China.

Cross-sectional Seroprevalence and Genotype of Hepatitis E Virus in Humans and Swine in a High-density Pig-farming Area in Central China

Hepatitis E virus(HEV)infection is a common public health problem in developing countries.However,the current prevalence of HEV and the relationship of HEV genotype between swine and human within high-density pig-farming areas in central China are still inadequately understood.Here,cross-sectional serological and genotypic surveys of HEV among the 1232 general population,273 workers occupationally exposed to swine,and 276 pigs in a high-density pig-breeding area,were undertaken by ELISA and nested RT-PCR methods.Anti-HEV IgG was detected in 26.22%of general population and 48.35%of occupational workers.The prevalence of swine serum HEV-Ag was 6.52%.The prevalence of anti-HEV IgG was significantly higher among the workers occupationally exposed to swine than among the general population.An increased HEV seropositivity risk among the general population was associated with either being a peasant or male and was very strongly associated with the increase of age.Among the occupationally exposed group,the prevalence of anti-HEV IgG antibodies increased with age and working years.Among the 30 HEV-IgM-positive people,the infection rates of clerks in the public,peasants,pork retailers,and pig farmers were higher than those of others.A phylogenetic analysis revealed that all the isolates belonged to subgenotype 4d,and four people and four pigs shared 97.04%-100%sequence homology.This study revealed a high HEV seroprevalence among the general population and workers occupationally exposed to swine in the Anlu City,and supports the notion that swine are a source of human HEV infection.

Fsh-Pc-Sce complex mediates active transcription of Cubitus interruptus （Ci）

表明小径的刺猬(Hh ) 在胚胎的开发和成年织物动态平衡起重要作用。如此的生物功能被抄写因素肘脉 interruptus (Ci ) 调停。然而，受动器 Ci 本身的 transcriptional 规定糟糕被调查。通过一幅基于 RNAi 的基因屏幕，我们识别了那女性无菌(1 ) homeotic (Fsh ) ，抄写激活剂，直接激活 Ci 抄写。生物化学试金在 Fsh 之中表明了物理相互作用，性梳子额外(Sce ) ，并且 Polycomb (Pc ) 。功能的试金进一步证明 Pc 和 Sce 为 Ci 被要求表示，没被 Engrailed 的 derepression 多半调停，) ， Ci 的一个抑压者，在 Pc 或 Sce 异种房间。最后，我们提供证明 Pc/Sce 在 Ci 地点便于 Fsh 的绑定并且在 Fsh 和 Pc 之间的物理相互作用为调停 Fsh 的 Ci 抄写是必要的证据。一起拿，我们不仅揭开那 Ci 被复杂的 Fsh-Pc-Sce transcriptionally 调整而且在 transcriptional 为在 Fsh 和 PcG 蛋白质之间的协作提供证据规定。

Simultaneous determination of Repaglinide and Irbesartan in biological plasmas using micellar enhanced excitation-emission matrix fluorescence coupled with ATLD method

A highly sensitive and selective 3D excitation-emission fluorescence method has been proposed to rapidly quantify the combined antidiabetics Repaglinide(Re) and Irbesartan(Ir) in rat and human plasmas with the aid of second-order calibration method based on alternating trilinear decomposition(ATLD) method. Re and Ir with weak fluorescence can be endowed with strong fluorescent property by changing the microenvironment in samples and improving the fluorescence quantum yield by using an appropriate micellar enhanced surfactant. The enhanced excitation-emission matrix fluorescence of Re and Ir can be accurately resolved and can simultaneously attain the optimal concentration even in the presence of a potentially strong intrinsic fluorescence from complex biological matrices, such as rat and human plasmas, by using the ATLD method, which completely exploits the "second-order advantage". The average recoveries of Re and Ir obtained from ATLD with the factor number of 3(N=3) were 101.0%±4.3% and 99.1%±4.1% for rat plasma and 100.5%±5.4% and 97.1%±3.6% for human plasma. Several statistical methods, including Student's t-test, figures of merit, and elliptical joint confidence region, have been utilized to evaluate the accuracy of the proposed method. Results show that the developed method can maintain second-order advantage in simultaneous determinations of the weak fluorescent analytes of interest in different biological plasma matrices.

Metabolic modulation of acetaminophen-induced hepatotoxicity by osteopontin

Induction of osteopontin(OPN),a well-known pro-inflammatory molecule,has been observed in acetaminophen(APAP)-induced hepatotoxicity.However,the precise cell source for OPN induction and its role during APAP-induced hepatotoxicity has not been fully explored.By employing a hepatotoxic mouse model induced by APAP overdose,we demonstrate that both serum and hepatic OPN levels were significantly elevated in response to APAP treatment.Our in vivo and in vitro studies clearly indicated that the induced expression of hepatic OPN was mainly located in necrosis areas and produced by dying or dead hepatocytes.Functional experiments showed that OPN deficiency protected against the APAP-induced liver injury by inhibiting the toxic APAP metabolism via reducing the expression of the cytochrome P450 family 2 subfamily E member 1(CYP2E1).Interestingly,this inhibition of CYP2E1 expression did not occur in unfasted Opn−/−mice,but was significant in fasted Opn−/−mice and maintained for 2hours after APAP challenge in fasted Opn−/−mice.In addition,despite the early protective role of OPN deficiency on APAP-induced hepatotoxicity,OPN deficiency retarded injury resolution by sensitizing hepatocytes to apoptosis and impairing liver regeneration.Finally,we demonstrated that a siRNA-mediated transient hepatic Opn knockdown could sufficiently and significantly protect animals from APAP-induced hepatotoxicity and death.In conclusion,this study clearly defines the cell source of OPN induction in response to APAP treatment,provides a novel insight into the metabolic role of OPN to APAP overdose,and suggests an Opn-targeted therapeutic strategy for the treatment or prevention of APAP-induced hepatotoxicity.

Waterborne sub-lethal exposure to perfluorobutanesulfonate causes intestinal dysbiosis in tadpoles of Lithobates catesbeianus

Perfluorobutanesulfonate (PFBS) is a ubiquitous pollutant in the aquatic environment, but its toxic effects andmechanisms on amphibian species remain largely unknown. In the present study, tadpoles (Lithobates catesbeianus) were exposed to various concentrations of PFBS (0, 1, 3, 10, and 30 μg/L) for 14 days, with the goal ofunveiling the impairment of intestinal health. Histopathological examination showed that sub-lethal exposure oftadpoles to PFBS at concentrations as low as 3 μg/L could result in the injury of intestinal structures. In a clearconcentration-dependent manner, the expressions of epithelial barrier components (i.e., Claudin 1 gene and tightjunction protein 2) were significantly decreased in PFBS-exposed intestines, while the intestinal content oflipopolysaccharide (LPS) and transcriptions of downstream responsive genes (e.g., TLR4, MyD88, and NF-κB) wereconcurrently significantly increased by exposure to 3, 10, and 30 μg/L of PFBS. As a consequence, the number ofeosinophils and expression of pro-inflammatory cytokines (e.g., IL-1β and TNF-α) were increased therein.Furthermore, PFBS exposure induced oxidative stress in intestinal tissues by increasing the level of reactive oxygen species (ROS) and suppressing antioxidant capacity. The transcriptional levels of CytoC and Bax genes aswell as activities of caspase 9 and caspase 3 enzymes were remarkably increased, while the transcript abundanceof Bcl-2 was down-regulated significantly after PFBS exposure, thereby favoring apoptosis in tadpole intestines.PFBS sub-lethal exposure also drove the composition of intestinal microbiota to a dysbiosis status. Correlationanalysis further revealed that the relative abundance of members of the genus Bosea was positively related withthe contents of LPS and IL-1β. Overall, the present study provides the first evidence for pronounced impacts ofPFBS on amphibian intestinal ecology, highlighting the susceptibility of tadpoles to the environmental risks ofPFBS.

Emerging roles of DJ-1 in liver diseases through regulation of oxidative stress and immune response

Reactive oxygen species(ROS)and immune response play critical roles in the progression of liver diseases.DJ-1,also known as Parkinson disease 7(Park7),is extensively expressed in cells and tissues,where it governs numerous biological functions including chaperone activity,protease function,transcriptional and mitochondrial regulation,and ROS modulation.Moreover,we have established that DJ-1 plays a critical role in initiating an inflammatory response by modulating ROS generation.Therefore,DJ-1 may play an important role in the progression of liver diseases by modulating ROS and the immune response.Recently,we have shown that DJ-1 deficiency negatively regulates proliferation of hepatic progenitor cells(HPCs)by impairing the formation of HPC-associated fibrosis and inflammatory niches.Deficiency of DJ-1 ameliorates liver fibrosis by inhibiting hepatic ROS production and inflammation;moreover,in a classic diethylnitrosamine(DEN)-mediated hepatocellular carcinoma(HCC)mouse model,deletion of DJ-1 ameliorates tumorigenesis and HCC cell proliferation by regulating hepatic inflammation and reducing the activity of the interleukin 6/signal transducer and activator of transcription 3(IL-6/STAT3)signaling pathway.Taken together,these data suggest a critical function for,and therapeutic value of,DJ-1 in treatment of liver diseases.The aim of this review is to summarize these functions and the underlying molecular mechanisms of DJ-1 in liver diseases,and to highlight the potential therapeutic value and future research direction of DJ-1 in liver diseases.