气候变化对商洛旱地冬小麦农艺性状的影响

研究近年来气候变化对商洛旱地冬小麦农艺性状的影响,旨在为商洛旱地冬小麦适应气候变化新品种选育提供理论指导。利用2010—2023年陕南丘陵地区商洛亚区小麦区域试验商州点记录的小麦品种小偃15农艺性状数据和商洛气象资料,统计分析小麦农艺性状和气候变化的趋势,并进行相关性、多元回归和通径分析。结果表明,近年来商洛年降水量、年平均气温以及小麦生育期降水量、气温均呈上升趋势;小麦不同生育阶段中,播种至越冬前、越冬期间、返青至孕穗期的降水量均呈上升趋势,而抽穗至成熟期降水量呈下降趋势;小麦各生育阶段的气温均呈上升趋势;小麦农艺性状穗长、穗粒数、千粒质量、有效穗数、产量均呈上升趋势,而生育期和株高呈下降趋势。相关性分析结果发现,全生育期平均气温与穗长呈极显著正相关,与穗粒数和产量均呈显著正相关,而与生育期呈极显著负相关;返青至孕穗期气温与生育期呈显著负相关;越冬期间降水量与穗长呈显著正相关;产量与穗长和穗粒数均呈极显著正相关。多元回归和通径分析结果发现,穗长、千粒质量、穗粒数、全生育期平均气温是决定产量的4个主要因子,它们共同决定了产量90.80%的变异。综合以上分析,为适应商洛地区气候变化,旱地小麦新品种选育过程中要重点关注穗长、穗粒数和生育期等性状。

Electrocatalytic CO_(2)reduction to syngas

While carbon dioxide(CO_(2))is a major greenhouse gas,it is also an important C1 resource.In the trend of energy conservation and emission reduction,electrocatalytic reduction has become a very promising strategy for CO_(2)utilization because it can convert CO_(2)directly to high-valued chemicals and fuels under mild conditions.In particular,the product CO and by-product H_(2)can be combined into syngas by an electrocatalytic CO_(2)reduction reaction(CO_(2)RR)in an aqueous medium.Different molar ratios of CO and H_(2)may be used to produce essential bulk chemicals or liquid fuels such as methanol,alkanes,and olefins through thermochemical catalysis,Fischer-Tropsch synthesis,microbial fermentation,and other techniques.This work discusses the latest strategies in controlling the molar ratio of CO/H_(2)and improving the yield of CO_(2)RR-to-syngas.The challenges of electrocatalytic syngas production are analyzed from an industrial application perspective,and the possible measures to overcome them are proposed in terms of new catalyst design,electrolyte innovation,flow reactor optimization,anodic reaction coupling,and operando technique application.

Hybrid data-driven and physics-based modeling for viscosity prediction of ionic liquids

Viscosity is one of the most important fundamental properties of fluids.However,accurate acquisition of viscosity for ionic liquids(ILs)remains a critical challenge.In this study,an approach integrating prior physical knowledge into the machine learning(ML)model was proposed to predict the viscosity reliably.The method was based on 16 quantum chemical descriptors determined from the first principles calculations and used as the input of the ML models to represent the size,structure,and interactions of the ILs.Three strategies based on the residuals of the COSMO-RS model were created as the output of ML,where the strategy directly using experimental data was also studied for comparison.The performance of six ML algorithms was compared in all strategies,and the CatBoost model was identified as the optimal one.The strategies employing the relative deviations were superior to that using the absolute deviation,and the relative ratio revealed the systematic prediction error of the COSMO-RS model.The CatBoost model based on the relative ratio achieved the highest prediction accuracy on the test set(R^(2)=0.9999,MAE=0.0325),reducing the average absolute relative deviation(AARD)in modeling from 52.45% to 1.54%.Features importance analysis indicated the average energy correction,solvation-free energy,and polarity moment were the key influencing the systematic deviation.

商洛主栽小麦品种苗期抗旱性综合评价

为明确商洛地区主栽小麦品种苗期抗旱性和筛选适宜抗旱鉴定指标,聚乙二醇(PEG-6000)模拟干旱胁迫,测定‘商麦5226’等8个品种苗期抗旱指标的变化。基于各指标的抗旱系数,通过主成分分析、聚类分析和隶属函数法对其抗旱性进行综合评价。结果表明:(1)与对照相比,干旱处理下叶片净光合速率、苗高、最大根长、根干质量、茎叶干质量有不同程度的下降;超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性、过氧化氢酶(CAT)活性、丙二醛(MDA)含量、脯氨酸含量、可溶性糖含量、可溶性蛋白则表现出增加的规律。(2)通过主成分分析,将中度干旱和严重干旱下的12个单项指标均转换为4个独立的综合指标,中度干旱下4个综合指标的贡献率依次为65.628%、14.890%、7.701%和6.511%,累计贡献率分别为94.730%,严重干旱下4个综合指标的贡献率依次为61.586%、18.087%、9.875%和5.696%,累计贡献率分别为95.244%;基于抗旱性综合评价值D,中度干旱下供试品种抗旱性分类4类、严重干旱下抗旱性分为3类,综合来看,‘小偃15’‘商麦5226’和‘商麦1619’为强抗旱性品种。(3)灰色关联分析表明,CAT活性、脯氨酸含量、根干质量、可溶性糖含量、净光合速率与综合评价值D关联度较为密切。研究结果可为旱地小麦品种选用(育)和抗旱性鉴定提供参考。

A Robust Framework for Multimodal Sentiment Analysis with Noisy Labels Generated from Distributed Data Annotation

Multimodal sentiment analysis utilizes multimodal data such as text,facial expressions and voice to detect people’s attitudes.With the advent of distributed data collection and annotation,we can easily obtain and share such multimodal data.However,due to professional discrepancies among annotators and lax quality control,noisy labels might be introduced.Recent research suggests that deep neural networks(DNNs)will overfit noisy labels,leading to the poor performance of the DNNs.To address this challenging problem,we present a Multimodal Robust Meta Learning framework(MRML)for multimodal sentiment analysis to resist noisy labels and correlate distinct modalities simultaneously.Specifically,we propose a two-layer fusion net to deeply fuse different modalities and improve the quality of the multimodal data features for label correction and network training.Besides,a multiple meta-learner(label corrector)strategy is proposed to enhance the label correction approach and prevent models from overfitting to noisy labels.We conducted experiments on three popular multimodal datasets to verify the superiority of ourmethod by comparing it with four baselines.

5个羊肚菌菌株的栽培与评价研究

[目的]本研究旨在探究商洛羊肚菌人工栽培常用品种特点,为商洛地区羊肚菌人工栽培菌种选择和新品种选育提供理论参考。[方法]对征集的5个商洛地区羊肚菌常用菌株G8(YD1)、幺妹(YD2)、草莓(YD3)、401(YD4)、191(YD5)进行菌种特性、亲缘关系、栽培比较、子实体形态特征研究,综合评价其在商洛地区的栽培适应性和产量稳定性。[结果]本研究中,YD1菌丝生长速度最快,其次为YD2;YD5菌株与其它4个菌株亲缘关系均较远,YD1与YD2菌株亲缘关系较远,初步判断YD5、YD1、YD2为3个不同菌株;YD1、YD2菌株菌丝活力旺盛,生育期适中(分别为140、145 d),产量适中(分别为3005.10、2888.10 kg·hm^(-2)),且菇型较好;YD3、YD4菌株菌丝活力旺盛,但生育期较长(均为151 d),产量偏低(分别为2194.05、2253.60 kg·hm^(-2)),菇型一般;YD5菌株菌丝活力旺盛,生育期最短(131 d),产量最高(3334.95 kg·hm^(-2)),且与其它4个菌株存在极显著差异,但菇型一般。[结论]因此在5个商洛地区常用羊肚菌菌种中,YD1、YD2菌株具有一定的推广价值,可作为主推品种在生产中应用;同时可有计划的推广应用YD5菌株,而YD3、YD4菌株菌丝产量较低,不易推广,应慎重选择。

核桃幼园套种条件下不同大豆品种高产稳产性及适应性分析

为筛选出适宜核桃幼园套种条件下的高产稳产且适应性好的大豆品种,以期提高商洛地区大豆的播种面积、产量和经济效益,采用显著性差异、变异系数、回归系数、高稳系数、聚类分析等方法综合评价了6个大豆品种的高产稳产性和适应性。结果显示:陕垦豆4号、陕豆125、齐黄34共3个品种为核桃幼园套种条件下高产稳产、适应性好的品种,且类群I(陕垦豆4号、陕豆125、齐黄34)平均株高为66.10 cm,平均单株荚数为81.53个,平均单株粒数为152.61粒,平均百粒质量为28.45 g,平均生育期为133.67 d的大豆品种及其类似品种在商洛核桃幼园套种条件下具有一定的优势。因此,陕垦豆4号、陕豆125、齐黄34,以及与其类似的品种可在商洛同类生态区核桃幼园中作为高产稳产大豆品种适当加以应用。本研究为商洛核桃幼园套种条件下大豆品种选择提供了理论参考。

我国医养结合研究的演变、热点与展望

分析我国近十年的医养结合研究的演变、热点和发展趋势,得出我国医养结合研究主要聚焦于医养结合具体模式研究和医养结合服务需求;医养结合研究呈现出研究内容持续深化、研究范围不断扩展、研究视野逐渐开阔的特点;医养结合研究嬗变可以分为起步阶段、发展阶段和深化阶段。未来医养结合研究应重点关注学科融合、医养结合服务公平性和个人健康信息保护。

Effect of Bcl-2 and Bax on survival of side population cells from hepatocellular carcinoma cells

AIM： To understand the role and significance of side population （SP） cells from hepatocellular carcinoma （HCC） in hepatocarcinogenesis, development, relapse and metastasis, we simulated the denutrition conditions that cancer cells experience in clinical therapy, observed the different anti-apoptosis ability of SP cells and non-SP cells under such conditions, and established the possible effects of P53, Bcl-2 and Bax on survival of SP cells. METHODS： We used flow cytometry to analyze and sort the SP and non-SP cells in established HCC lines MHCC97 and hHCC. We evaluated cell proliferation by methyl thiazolyl tetrazolium （MTT） assay and investigated the expression of p53, bcl-2 and bax genes during denutrition, by RT-PCR and immunofluorescence staining. RESULTS： The percentage of SP cells in the two established HCC lines was 0.25% and 0.5%, respectively. SP cells had greater anti-apoptosis and proliferation ability than non-SP cells. Expression of Bcl-2 and Bax in SP and non-SP cells differed during denutrition. The former was up-regulated in SP cells, and the latter was up-regulated in non-SP cells. CONCLUSION： It may be that different upstream molecules acted and led to different expression levels of Bcl-2 and Bax in these two cell lines. There was a direct relationship between up-regulation of Bcl-2 and down-regulation of Bax and higher anti-apoptosis ability in SP cells. It may be that the existence and activity of SP cells are partly responsible for some of the clinical phenomena which are seen in HCC, such as relapse or metastasis. Further research on SP cells may have potential applications in the field of anticancer therapy.

Gegen Qinlian decoction enhances immunity and protects intestinal barrier function in colorectal cancer patients via gut microbiota

BACKGROUND We previously showed,using the Traditional Chinese Medicine System Pharmacology Database,that Gegen Qinlian decoction(GQD)had a direct antitumor effect,and was combined with programmed cell death protein(PD)-1 inhibitors to treat microsatellite stable(MSS)tumor-bearing mice.However,the effect of GQD on patients with colorectal cancer(CRC)is not clear.AIM To determine the therapeutic mechanism of GQD in improving immune function,reducing inflammation and protecting intestinal barrier function.METHODS Seventy patients with CRC were included in this study:37 in the control group and 33 in the treatment group.The proportions of CD4+T,CD8+T,natural killer(NK),NKT and T regulatory cells were measured by flow cytometry.Levels of the cytokines tumor necrosis factor(TNF)-α,interferon(IFN)-γ,interleukin(IL)-2,IL-6,IL-10 and serotonin(5-hydroxytryptamine;5-HT)in serum were assessed by enzyme-linked immunosorbent assay(ELISA).The expression of zonula occludens(ZO)-1,occludin,nuclear factor(NF)-κB and TNF-αin tumor and normal tissues was measured by immunohistochemistry.The composition of gut microbiota from patients in the treatment group was assessed using 16S rDNA analysis.RESULTS There were no adverse events in the treatment group.The proportion of CD4+T cells and NKT cells in the post-treatment group was significantly higher than that in the pre-treatment and control groups(P<0.05).The level of TNF-αin the posttreatment group was significantly lower than that in the pre-treatment and control groups(P<0.05).The concentration of 5-HT in the post-treatment group was significantly lower than that in the pre-treatment group(P<0.05).The expression of ZO-1 and occludin in tumor tissues in the treatment group was significantly higher than that in the control group(P<0.05).The expression of ZO-1 in normal tissues of the treatment group was significantly higher than that in the control group(P=0.010).Compared with the control group,expression of NF-κB and TNF-αin tumor tissues of the treatment group was significantly decreased(P<0.05).Compared with the pre-treatment group,GQD decreased the relative abundance of Megamonas and Veillonella.In addition,GQD increased the relative abundance of Bacteroides,Akkermansia and Prevotella.CONCLUSION GQD enhances immunity and protects intestinal barrier function in patients with CRC by regulating the composition of gut microbiota.

Prediction of gastric cancer metastasis through urinary metabolomic investigation using GC/MS

AIM:To gain new insights into tumor metabolism and to identify possible biomarkers with potential diagnostic values to predict tumor metastasis.METHODS:Human gastric cancer SGC-7901 cells were implanted into 24 severe combined immune deficiency (SCID) mice,which were randomly divided into metastasis group (n=8),non-metastasis group (n=8),and normal group (n=8).Urinary metabolomic information was obtained by gas chromatography/mass spectrometry (GC/MS).RESULTS:There were significant metabolic differences among the three groups (t test,P < 0.05).Ten selected metabolites were different between normal and cancer groups (non-metastasis and metastasis groups),and seven metabolites were also different between non-metastasis and metastasis groups.Two diagnostic models for gastric cancer and metastasis were constructed respectively by the principal component analysis (PCA).These PCA models were confirmed by corresponding receiver operating characteristic analysis (area under the curve=1.00).CONCLUSION:The urinary metabolomic profile is different,and the selected metabolites might be instructive to clinical diagnosis or screening metastasis for gastric cancer.

Monochromatic green light stimulation during incubation shortened the hatching time via pineal function in White Leghorn eggs

Background:Effect of monochromatic green light illumination on embryo development has been reported in chickens.The avian pineal gland is an important photo-endocrine organ formed by a mediodorsal protrusion during embryonic development.However,the involvement of pineal gland in the light transduction process remains to be elucidated.In the present study,we investigated the influence of monochromatic green light on hatching time and explored the possible mechanism via pineal function.Results:A total of 600 eggs of White Leghorn(Shaver strain)were incubated under photoperiods of either 12 h of light and 12 h of darkness using monochromatic green light(12L:12D group)or 24 h of darkness(0L:24D group)for 18 d.Compared to 0L:24D group,the green light stimulation shortened the hatching time without extending the hatch window or impairing hatchability.The liver of embryos incubated in the 12L:12D light condition was heavier than those of the 0L:24D group on d 21 post incubation which may be linked to the observed increase in the serum concentration of insulin-like growth factor 1(IGF-1);primary secretion of the liver.Histological structure analysis of pineal gland demonstrated that the light stimulation increased follicle area,wall thickness and lumen area on d 10 and d 12 post incubation.Rhythmic function analysis demonstrated that three clock related genes(brain and muscle ARNT-like-1,BMAL1;circadian locomotor output cycles kaput,CLOCK;and cryptochrome-1,CRY1)and a melatonin rate-limiting enzyme related gene(arylalkylamine N-acetyltransferase,AANAT)were rhythmically expressed in the pineal gland of the 12L:12D group,but not in the 0L:24D group.Simultaneously,the light stimulation also increased the concentration of melatonin(MT),which was linked to hepatocyte proliferation and IGF-1 secretion in previous studies.Conclusions:The 12L:12D monochromatic green light stimulation during incubation shortened hatching time without impairing hatching performance.Pineal gland’s early histological development and maturation of its rhythmic function were accelerated by the light stimulation.It may be the key organ in the photo-endocrine axis that regulates embryo development,and the potential mechanism could be through enhanced secretion of MT in the 12L:12D group which promotes the secretion of IGF-1.

两种抗VEGF药物治疗1型早产儿视网膜病变的疗效比较

目的:比较玻璃体腔注射康柏西普和雷珠单抗治疗1型早产儿视网膜病变(ROP)的有效性和安全性。方法:回顾性收集2018-08/2020-01于西京医院眼科确诊为1型ROP,并进行玻璃体腔注射康柏西普(IVC组,46例91眼)或雷珠单抗(IVR组,55例109眼)治疗的患儿临床资料,比较治疗后两组患儿ROP病变消退、复发及再治疗情况,不良预后及眼部和全身并发症情况。结果:纳入患儿101例200眼中急进型后极部ROP(AP-ROP)20眼,阈值期ROP 86眼,阈值前期1型ROP 94眼。两组患儿基线资料及治疗前ROP严重程度均无差异(P>0.05)。IVC组和IVR组一次治愈率无差异(93.4%vs 87.2%,P>0.05)。一次治疗后IVC组复发6眼(6.6%),平均复发时间为11.7±4.13wk,其中2眼再次行IVC治疗,4眼行视网膜激光光凝治疗,治疗后病变均消退;IVR组复发11眼(10.1%),平均复发时间9.82±4.02wk,其中4眼再次行IVR治疗,7眼行视网膜激光光凝治疗,治疗后病变均退行;两组复发率及复发时间均无显著差异(P>0.05)。IVC组一次治疗后未见病变进展;IVR组一次治疗后3眼病情进展,其中2眼视网膜增殖加重伴出血,行视网膜激光光凝治疗,1眼进展为牵拉性视网膜脱离,行玻璃体切除术治疗。两组患儿治疗后均未出现与药物或玻璃体腔注射相关的眼部及全身并发症,IVR组3眼出现颞侧视网膜皱褶,视网膜血管牵拉致血管弓夹角变小等不良预后。结论:IVC和IVR均为1型ROP治疗的有效手段,两者一次治愈率、复发率无显著差异,但IVR治疗的部分病情严重患儿有出现病变进展或不良预后的可能,需长期严密观察随访。

Progress in the Study of False Smut Disease in Rice

Rice false smut disease is an increasing concern for research and production, not only because of the increasing epidemic occurrence in rice production, but also the intriguing specific pathogenesis of the disease to be a unique pathological system to enrich the molecular mechanism of plant-microbe interaction. Progresses have been achieved in the pathogen phylogenetic placement, the alternative hosts, the pathogen morphology and diversity, the toxins generated by false smut balls, the artificial inoculation method, and the pathogen transformation as well as rice resistance to the disease. However, it is still controversy on the infection process. It is not clear how the life cycle of this pathogen is coupled with the disease cycle. This review summarized our current understanding on the pathogen, the pathogenesis, and the rice resistance to the disease. Future work should pay attention to developing a more rapid and effective system to evaluate rice resistance and susceptibility to the disease, screening of rice germplasm for disease-resistance breeding, studying the resistance inheritance, and investigating the molecular mechanism of rice-false smut fungus interaction.

Dihydromyricetin ameliorates chronic liver injury by reducing pyroptosis

BACKGROUND Chronic liver injury(CLI) is now a worldwide disease. However, there is no effective treatment. Pyroptosis plays an essential role in CLI. Dihydromyricetin(DHM) resists oxidation and protects the liver. We hypothesize that the beneficial effect of DHM on CLI is related to its effect on the expression of pyroptosisrelated molecules. Therefore, we studied the influence of DHM on CLI and pyroptosis.AIM To study the role of pyroptosis in the pathogenesis of CLI and the therapeutic mechanism of DHM.METHODS Thirty-two mice were randomly divided into four groups: The control group was injected with olive oil, the carbon tetrachloride(CCl4) group was injected with CCl4, the vehicle group was injected with hydroxypropyl-β-cyclodextrin while injecting CCl4 and the DHM group was injected with DHM while injecting CCl4. After four weeks of treatment, liver tissues from the mice were stained with hematoxylin and eosin, and oil red O. Blood was collected from the angular vein for serological analysis. The severity of CLI was estimated. Some liver tissue was sampled for immunohistochemistry, Western blotting and quantitative reverse transcription PCR to observe the changes in pyroptosis-related molecules.RESULTS Serum total cholesterol, low density lipoprotein, aspartate aminotransferase(AST) and alanine aminotransferase(ALT) in the CCl4 group were higher than those in the control group, and serum total cholesterol, low density lipoprotein, AST and ALT in the DHM group were lower than those in the vehicle group. Hematoxylin and eosin and oil red O staining showed that there were more lipid droplets in the CCl4 group than in the control group, and there were fewer lipid droplets in the DHM group than in the vehicle group. Western blotting showed that the expression of the pyroptosis-related molecules caspase-1, NOD-, LRR-and pyrin domain-containing 3(NLRP3) and gasdermin D(GSDMD)-N in the CCl4 group was higher than that in the control group, while expression of these proteins in the DHM group was lower than that in the vehicle group. Quantitative reverse transcription PCR results showed that the expression of the pyroptosis-related genes caspase-1, NLRP3, GSDMD and interleukin-1β(IL-1β) in the CCl4 group was higher than that in the control group, while there was no significant change in NLRP3 and caspase-1 expression in the DHM group compared with that in the vehicle group, and the expression of GSDMD and IL-1β was decreased.CONCLUSION DHM improves CCl4-induced CLI and regulates the pyroptosis pathway in hepatocytes. DHM may be a potential therapeutic agent for CLI.

Hemodynamic changes in hepatic sinusoids of hepatic steatosis mice

BACKGROUND Fatty liver(FL) is now a worldwide disease. For decades, researchers have been kept trying to elucidate the mechanism of FL at the molecular level, but rarely involve the study of morphology and medical physics. Traditionally, it was believed that hemodynamic changes occur only when fibrosis occurs, but it has been proved that these changes already show in steatosis stage, which may help to reveal the pathogenesis and its progress. Because the pseudolobules are not formed during the steatosis stage, this phenomenon may be caused by the compression of the liver microcirculation and changes in the hemodynamics.AIM To understand the pathogenesis of hepatic steatosis and to study the hemodynamic changes associated with hepatic steatosis.METHODS Eight-week-old male C57 BL/6 mice were divided into three groups randomly(control group, 2-wk group, and 4-wk group), with 16 mice per group. A hepatic steatosis model was established by subcutaneous injection of carbon tetrachloride in mice. After establishing the model, liver tissue from mice was stained with hematoxylin and eosin(HE), and oil red O stains. Blood was collected from the angular vein, and hemorheological parameters were estimated. A two-photon fluorescence microscope was used to examine the flow properties of red blood cells in the hepatic sinusoids.RESULTS Oil red O staining indicated lipid accumulation in the liver after CCl_4 treatment.HE staining indicated narrowing of the hepatic sinusoidal vessels. No significant difference was observed between the 2-wk and 4-wk groups of mice onmorphological examination. Hemorheological tests included whole blood viscosity(mPas, γ = 10 s-1/γ = 100 s-1)(8.83 ± 2.22/4.69 ± 1.16, 7.73 ± 2.46/4.22 ±1.32, and 8.06 ± 2.88/4.22 ± 1.50), red blood cell volume(%)(51.00 ± 4.00, 42.00 ±5.00, and 40.00 ± 3.00), the content of plasma fibrinase(g/L)(3.80 ± 0.50, 2.90 ±0.80, and 2.30 ± 0.70), erythrocyte deformation index(%)(44.49 ± 5.81, 48.00 ±15.29, and 44.36 ± 15.01), erythrocyte electrophoresis rate(mm/s per V/m)(0.55 ±0.11, 0.50 ± 0.11, and 0.60 ± 0.20), revealing pathological changes in plasma components and red blood cells of hepatic steatosis. Assessment of blood flow velocity in the hepatic sinusoids with a laser Doppler flowmeter(mL/min per100 g)(94.43 ± 14.64, 80.00 ± 12.12, and 67.26 ± 5.92) and two-photon laser scanning microscope(μm/s)(325.68 ± 112.66, 213.53 ± 65.33, and 173.26 ± 44.02)revealed that as the modeling time increased, the blood flow velocity in the hepatic sinusoids decreased gradually, and the diameter of the hepatic sinusoids became smaller(μm)(10.28 ± 1.40, 6.84 ± 0.93, and 5.82 ± 0.79).CONCLUSION The inner diameter of the hepatic sinusoids decreases along with the decrease in the blood flow velocity within the sinusoids and the changes in the systemic hemorheology.

Electrophysiological changes of autonomic cells in left ventricular outflow tract in guinea pigs with iron deficiency anemia complicated with chronic heart failure

Objective: To investigate the electrophysiological changes of autonomic cells in left ventricular outflow tract in guinea pigs with iron deficiency anemia complicated with chronic heart failure.Methods: Guinea pigs model of iron deficiency anemia complicated with chronic heart failure in 10 guinea pigs of the experimental group was made by feeding a low iron diet,pure water and subcutaneous injection of isoproterenol. The control group consisting of 11 guinea pigs was given normal food, normal water and injected with normal saline. The left ventricular outflow tract model specimen was also prepared. The standard microelectrode technique was used to observe electrophysiological changes of autonomic cells in the outflow tract of left ventricular heart failure complicated with iron deficiency anemia in guinea pig model. The indicators of observation were maximal diastolic potential, action potential amplitude, 0 phase maximal depolarization velocity, 4 phase automatic depolarization velocity, repolarization 50% and 90%, and spontaneous discharge frequency.Results: Compared with the control group, 4 phase automatic depolarization velocity,spontaneous discharge frequency and 0 phase maximal depolarization velocity decreased significantly(P < 0.01) and action potential amplitude reduced(P < 0.01) in model group. Moreover, repolarization 50% and 90% increased(P < 0.01).Conclusions: There are electrophysiological abnormalities of the left ventricular outflow tract in guinea pigs with iron deficiency anemia complicated with heart failure.

Effect of iron overload on electrophysiology of slow reaction autorhythmic cells of left ventricular outflow tract in guinea pigs

Objective: To investigate the electrophysiology effects and mechanism of iron overload on the slow response autorhythmic cells in the left ventricular outflow tract of guinea pigs.Methods: Standard microelectrode cell recording techniques were adopted to observe the electrophysiological effects of different concentrations of Fe^(2+)(100 μmol/L, 200 μmol/L) on the left ventricular outflow tract autorhythmic cells.Heart tissues were perfused with FeSO_4(200 μmol/L) combing with CaCl_2(4.2 mmol/L), Verapamil,(1 μmol/L), and nickel chloride(200μmol/L) respectively to observe the influences of these contents on electrophysiology of FeSO_4(200μmol/L) on the left ventricular outflow tract autorhythmic cells.Results: Fe^(2+)at both 100 μmol/L and 200 μmol/L could change the electrophysiological parameters of the slow response autorhythmic cells of the left ventricular outflow tract in a concentrationdependent manner resulting into decrease in Vmax, APA and MDP, slower RPF and VDD, and prolonged APD_(50) and APD_(90)(P all <0.05).Besides, perfusion of increased Ca^(2+) concentration could partially offset the electrophysiological effects of Fe^(2+)(200 μmol/L).The L-type calcium channel(LTCC) blocker Verapamil(1 μmol/L) could block the electrophysiological effects of Fe^(2+)(200 μmol/L).But the T-type calcium channel(TTCC) blocker nickel chloride(NiCl_2, 200 μmol/L) could not block the electrophysiological effects of Fe^(2+)(200 μmol/L).Conclusions: Fe^(2+) can directly change the electrophysiological characteristics of the slow response autorhythmic cells of the left ventricular outflow tract probably through the L-type calcium channel.

The Variation of Stone Cell Content in 236 Germplasms of Sand Pear(Pyrus pyrifolia)and Identification of Related Candidate Genes

Stone cells have been described to substantially influence pear fruit quality,as lignin and cellulose are the main components of stone cells.However,there are limited studies on the relationship between the variation and molecular basis of stone cells,lignin and cellulose content among different pear varieties.Here,to reveal the variation of stone cell content within different cultivated species,we collected 236 germplasms of sand pear(Pyrus pyrifolia)at 50 days after flower blooming(DAFB),the key stage of stone cell formation.In our results,we measured the content of stone cells,lignin and cellulose and found that these contents ranged from2.82%to 29.00%,8.84%to 55.30%and 11.52%to 30.55%,respectively.Further analysis showed that the variation coefficient of stone cell,lignin and cellulose content was 39.10%,28.03%and 16.71%,respectively.Additionally,a significant correlation between stone cell,lignin and cellulose content were detected,and the correlation coefficient between the contents of stone cell and lignin(0.912)was higher than between the contents of stone cell and cellulose(0.796).Moreover,the average lignin content(29.73%)was higher than the average cellulose content(18.03%)in stone cells in pear fruits,indicating that lignin is the main component of stone cell in pears.Finally,on the basic of the transcriptome data,we identified 10 transcription factors belonging to bHLH,ERF,MYB,and NAC transcript families,which might be involved in lignin formation in stone cells.qRT-PCR experiments verified coincident trends between expression of candidate genes and stone cell content.This research laid foundation for future studies on genetic variation of stone cells in pear fruits and provided important gene resources for stone cell regulation.

Deformation behavior and plastic instability of boronized Al0.25CoCrFeNi high-entropy alloys

Using thermochemical treatments,boronized layers were successfully prepared on Al0.25CoCrFeNi high-entropy alloys(HEAs).The thickness of the boronized layers ranged widely from 20 to 50μm,depending on the heat treatment time.Boronizing remarkably improved the surface hardness from HV 188 to HV 1265 after treating at 900°C for 9 h.Moreover,boronizing enhanced the yield strength of HEAs from 195 to 265 MPa but deteriorated the tensile ductility.Multiple crackings in the boride layers significantly decreased the plasticity.The insufficient work-hardening capacity essentially facilitated the plastic instability of the boronized HEAs.With decreasing substrate thickness,the fracture modes gradually transformed from dimples to quasi-cleavage and eventually to cleavage.