Transcriptomic and metabolomic analysis of changes in grain weight potential induced by water stress in wheat

The sink strength of developing ovaries in wheat determines the grain weight potential.The period from booting to the grain setting stage is critical for ovary growth and development and potential sink capacity determination.However,the underlying regulatory mechanism during this period by which the wheat plant balances and coordinates the floret number and ovary/grain weight under water stress has not been clarified.Therefore,we designed two irrigation treatments of W0(no seasonal irrigation)and W1(additional 75 mm of irrigation at the jointing stage)and analyzed the responses of the ovary/grain weight to water stress at the phenotypic,metabolomic,and transcriptomic levels.The results showed that the W0 irrigation treatment reduced the soil water content,plant height,and green area of the flag leaf,thus reducing grain number,especially for the inferior grains.However,it improved the grain weight of the superior and inferior grains as well as average grain weight at maturity,while the average ovary/grain weight and volume during–3 to 10 days after anthesis(DAA)also increased.Transcriptomic analysis indicated that the genes involved in both sucrose metabolism and phytohormone signal transduction were prominently accelerated by the W0 treatment,accompanied by greater enzymatic activities of soluble acid invertase(SAI)and sucrose synthase(Sus)and elevated abscisic acid(ABA)and indole-3-acetic acid(IAA)levels.Thus,the sucrose content decreased,while the glucose and fructose contents increased.In addition,several TaTPP genes(especially TaTPP-6)were down-regulated and the IAA biosynthesis genes TaTAR1 and TaTAR2 were up-regulated under the W0 treatment before anthesis,which further increased the IAA level.Collectively,water stress reduced the growth of vegetative organs and eliminated most of the inferior grains,but increased the ABA and IAA levels of the surviving ovaries/grains,promoting the enzymatic activity of Sus and degrading sucrose into glucose and fructose.As a result,the strong sucrose utilization ability,the enhanced enzymatic activity of SAI and the ABA-and IAA-mediated signaling jointly increased the weight and volume of the surviving ovaries/grains,and ultimately achieved the tradeoff between ovary/grain weight and number in wheat under water stress.

Beneficial effect of sulphate-bicarbonate-calcium water on gallstone risk and weight control

AIM： To investigate the effect of drinking sulphate-bi- carbonate-calcium thermal water （TW） on risk factors for atherosclerosis and cholesterol gallstone disease.

An approach for optimization of the wall thickness (weight) of a thick-walled cylinder under axially non-uniform internal service pressure distribution

Today, improving the weight/load carrying capacity ratio of a part is the matter of studies in most of the scientific and industrial areas.Autofrettage dimensions, the amount of material removed from outer and inner radius while manufacturing and the service pressure applied affect the residual stress distribution throughout the wall thickness and hence the load-bearing capacity of a thick-walled cylinder. Calculation of residual stresses after autofrettage process and optimization of autofrettage outline dimensions by using the amount of service pressures applied are common issues in literature.In this study, mandrel-cylinder tube interference dimensions were renovated by using traditional methods for swage autofrettage process of a gun barrel. Also, the residual stresses in the cylinder after autofrettage process, inside and outside material removal process and the variable service pressure throughout the cylinder applied were taken into consideration and incorporated into the design. By using the constrained optimization method, wall thickness(thus the weight) was optimized(minimized)to achieve the specified safety factor along the length of the cylinder. For the same cylinder, the results of the suggested analytical/with residual stress calculation approach were compared to analytical/without residual stress calculation results and numerical topology optimization method calculation results. Since the experimental measurement results are not yet available, it was not possible to compare them with the calculation results.The suggested approach enabled 22.9% extra weight reduction in proportion to numerical topology optimization and enabled 4.2% extra weight reduction in proportion to analytical/without residual stress optimization.Using this approach, the gain from residual stresses after autofrettage operation, the loss of residual stresses after material removal, and the effects of service pressures can be taken into account for each stage of design.

Optimization of food deprivation and sucrose preference test in SD rat model undergoing chronic unpredictable mild stress

Background:The chronic unpredictable mild stress(CUMS)model has long been considered the best model for exploring the pathophysiological mechanisms underlying depression.However,there are no widely recognised standards for strategies for modeling and for behavioral testing.The present study aimed to optimize the protocols for food deprivation and the sucrose preference test(SPT)for the CUMS model.Methods:We first evaluated the effects of different long periods of food deprivation on the body weight of Sprague Dawley(SD)rats by testing food deprivation for 24 hours(8:00-8:00^+),food deprivation for 12 hours during the daytime(8:00-20:00)and food deprivation for 12 hours at night(20:00-8:00^+).Next,we established a SD rat CUMS model with 15 different stimulations,and used body weight measurement,SPT,forced swim test(FST),open field test(OFT)and Morris water maze(MWM)test to verify the success of the modeling.In the SPT,consumption of sucrose and pure water within 1 and 12 hours was measured.Results:Twelve hours of food deprivation during the daytime(8:00-20:00)had no effect on body weight,while 12 hours of food deprivation at night(20:00-8:00^+)and 24 hours of food deprivation(8:00-8:00^+)significantly reduced the mean body weight of the SD rats.When SPT was used to verify the successful establishment of the CUMS rat model,sucrose consumption measured within 12 hours was less variable than that measured within 1 hour.Conclusions:Twelve hours of food deprivation in the daytime(8:00-20:00)may be considered a mild stimulus for the establishment of a CUMS rat model.Measuring sucrose consumption over 12 hours is recommended for SPT.

Healing Wounds under Mechanical Stress: A Case Example

This paper challenges the concept that the essential element in wound healing is to offload pressure. We suggest a change in approach that recognizes the integumentary system as one which, like all other body systems, adapts to the stresses put upon it. We use a clinical case example to illustrate the use of intentional mechanical stress to promote wound healing and include a review of the relevant literature. The intent of this publication is to call for a new look at clinical practice regarding wound healing and to call for future research directed at investigation of this theory.

咸淡水组合灌溉对土壤盐分和棉花生长的影响

为揭示不同微咸水(农田排水)与淡水在“先咸后淡”的组合灌溉模式下对土壤容重、盐分迁移和棉花生长的影响。以淡水灌溉为对照(CK),设置7种不同微咸水、淡水组合灌溉(微咸水∶淡水=1∶14(T1)、2∶13(T2)、3∶12(T3)、6∶9(T4)、9∶6(T5)、12∶3(T6)),T7处理采用全额微咸水灌溉,于2022年4-9月进行了棉花田间试验。结果表明,采用微咸水灌溉造成土壤表层盐分积累,0~40 cm土层出现积盐现象,棉花生育期结束后,各处理与淡水对照(CK)比较,T1~T6在0~40 cm土层的电导率分别增加1.16%~26.61%,T7处理电导率增加86.40%;与淡水对照相比,组合灌溉后各处理土层0~40 cm土壤容重明显增加,土壤孔隙度降低,以全额微咸水灌溉T7处理最为显著(容重增加10.24%);微咸水组合灌溉有效提高棉花株高、叶面积指数、茎粗。合理利用微咸水组合灌溉能够为棉花生长提供良好的水盐环境,提高棉花产量,能够为极端干旱区合理利用微咸水提供一种新的灌水模式,为灌区发展节水灌溉及农业可持续发展提供理论支撑。

基于正交试验泵加压输水管线空气罐参数优化

为探究空气罐在泵加压输水管线发生停泵水锤时,正、负压防护效果影响因子排序,寻求最优参数组合提高空气罐防护效果。基于新疆某输水工程,采用4因素4水平的正交试验方法,使用KYPIPE软件进行水力过渡过程模拟计算,建立正、负压防护效率评价指标对防护效果进行评价;采用熵权法将多目标优化转化为单目标优化,给出正、负压有效防护效率的权重分别为0.27、0.73。结果表明,对水锤防护效果影响最显著的因素为初始气体压力水头。各因素对正压防护效果影响大小排序为初始气体压力水头>入流阻力系数>出流阻力系数>高度直径比;对负压防护效果影响大小排序为初始气体压力水头>出流阻力系数>高度直径比>入流阻力系数;最优方案参数组合为初始气体压力水头为30 m、高度直径比为4、入流阻力系数为10、出流阻力系数为5;对比原方案,优化方案下最大正压降低15.8%,正压有效防护效率提高17.4%;最小负压增加60%,负压有效防护效率提高120%。

基于LightGBM的水厂供水压力预测

针对城市供水管网调度问题,提出一种基于LightGBM(Light Gradient Boosting Machine)的水厂供水压力预测模型。对压力监测点历史数据提取时间特征,并根据特征重要性对测压点排序,以特征权重筛选、特征权重与经验相结合两种方式选取控制点。以南方某城市供水系统为算例,结果表明采用特征权重分析、人工经验相结合选用控制点来预测,具有较高和稳定的预测精度。

碾压混凝土坝层间开裂过程模拟

针对碾压混凝土坝施工层面开裂破坏模拟问题,从混凝土细观结构角度出发,首先利用块体切割算法,生成了碾压混凝土坝随机骨料模型;然后,通过黏结单元嵌入算法,建立了坝体黏结裂缝模型;最后,利用Abaqus模拟了坝体层间开裂过程。实例模拟得出:当水容重超载系数为60时,坝体上游面拐点处的层面先出现裂缝,该区域应力集中现象明显;混凝土碾压坝在施工中,应避免在坝体轮廓拐点处分层。该研究可为碾压混凝土坝施工层面开裂破坏的预测提供参考。

The Effect of Mineral Composition and Quantity of Fines on the Atterberg Limits and Compaction Characteristics of Soils

Because of the various elements that come into play in natural soil formation, the impact of varied proportions of mineral composition and fines amount on Atterberg limits and compaction characteristics of soils is not well known. Three distinct soil samples were used in this investigation. The findings indicated the effect of varied mineral composition proportions and fines amount on the liquid limit, plastic limit, and plasticity index as assessed by the Casagrande test and hand-rolling method. The fluctuation of maximum dry density and optimal moisture content with these three soils has also been studied. Furthermore, correlations were established to indicate the compaction parameters and the amount of minerals and particles in the soil. The data show that the mineral content of the soil has a direct impact on the Atterberg limits and compaction characteristics. Soils containing larger percentages of expansive minerals, such as montmorillonite, have more flexibility and volume change capability. Mineral composition influences compaction parameters such as maximum dry density, ideal water content, axial strain, and axial stress. Soils with a larger proportion of fines, such as Soil 2 and Soil 3, have stronger flexibility and lower compaction qualities, with higher ideal water content and lower maximum dry density. Soil 1 has moderate flexibility and intermediate compaction qualities due to its low fines percentage. The effect of different mineral compositions and fines on the Atterberg limits and compaction characteristics of soils can be used to predict the behavior of compacted soils encountered in engineering practices, reducing the time and effort required to assess soil suitability for engineering use.

超高压容器开孔处裂纹最深点处应力强度因子的计算方法

由于超高压容器开孔处的应力梯度变化很大,通常由最小二乘法拟合的三次多项式往往与实际的应力分布之间存在较大偏差。针对这一问题,提出了一种分段插值求解的计算方法。首先,基于应力强度因子及通用权函数的理论,推导出了常数插值、线性插值、二次插值求解的计算公式;其次,结合工程实例,基于无裂纹体的弹性应力分析,对比分析了常规最小二乘法与常数插值、线性插值、二次插值的应力分布表征精度及应力强度因子计算结果,确定了线性插值和二次插值方法的可靠性;然后,分析了数据采集量对线性插值和二次插值计算结果的影响,确定了线性插值方法的实用性;最后,对线性插值与有限元分析的计算结果进行了分析验证。研究结果表明:应力分布表征精度为“最小二乘法<常数插值<线性插值<二次插值”,计算结果相对误差约为15%;随着采集数据量的增加,采用线性插值方法的计算结果能较快收敛,更适合于工程计算;线性插值与有限元法的计算结果高度一致,证明了线性插值计算的可靠性。

煤层气开发L型井水平井排采工程的研究

研究L型水平井的举升系统选型以及排采生产制度的设计,形成举升系统选型的方法,建立排采生产制度的设计模型;以在排采的L型水平井生产工程、煤粉形态为依据,总结L型井各排采举升系统的优劣势;从排采过程管控的重点与难点进行分析,研究L型水平井排采生产制度的动态设计,建立“区块生产制度”,单井“差异化生产制度”实现区块产能目标最大化。

基于压力-状态-响应的熵权-物元水生态文明评价模型

为了对区域水生态文明水平进行评价,针对目前水生态文明评价存在的问题,探讨水生态文明的内涵和评价方法。运用压力-状态-响应模型(press-state-response,PSR)提出由3类要素20种指标所组成的水生态文明评价指标体系;利用客观的熵权法求指标权重,减少了人为主观性对评价结果的干扰;利用物元分析方法有效解决了评价指标的模糊性和不相容性等问题,通过构造水生态文明的经典物元和节域物元,分析各个指标对应评价等级的关联度,构建了基于PSR的熵权-物元水生态文明综合评判模型。以济南市南部郊区为例进行研究,求得2010、2013、2015年水生态文明评价结果并对指标进行灵敏度分析,结果表明济南郊区水生态文明水平总体在逐渐提升,但水生态系统的压力没有明显减小,减少氨氮和化学需氧量污染物的排放是提升当地水生态文明水平的关键措施。该文模型能够揭示水生态文明现实状态和存在的问题,评价方法可供类似区域开展水生态文明评价参考。

高温高压条件下花岗岩切削破碎试验研究

为了达到最接近实际工程的试验效果,采用中国矿业大学的"20MN伺服控制高温高压岩体三轴试验机",设计了精确的加压和旋转系统,操作控制比较方便,测量数据准确。利用大尺寸(φ200mm×400mm)花岗岩试样和工程钻头(φ30mm的PDC钻头),使试验条件更加接近实际工程情况,开创了该类大试样试验的先河。通过正交试验研究花岗岩在高温高压状态下的切削破碎规律,得出以下结论:(1)高围压状态(100MPa)下,随着温度升高,花岗岩的可切削性逐渐增强,在超过一定的钻压时,切削速度随着温度的升高而明显增大,在755N钻压下,300℃的切削速度比室温时增大30%～50%;(2)高围压状态(100MPa)下,随着温度升高,单位破岩能耗明显降低,在钻压为755N时,300℃时的单位破岩能耗比室温时降低20%～30%;(3)在高温高压环境下,切削速度随着钻压或转速的增大而增大;单位破岩能耗随着转速的增大而增大,随着钻压的增大而减小,与室温无围压状态下的切削破碎规律基本一致;(4)由于花岗岩在此温压范围内属于渐进破坏,抗压强度下降缓慢,如果钻压太低则切削速度和单位破岩能耗受温度影响很小,为了在高温下取得对花岗岩的良好切削效果,钻压需要超过一定的值。

吹填土自重沉淤阶段孔隙水压力消散的试验研究

利用真空预压法处理吹填土时,细颗粒常堵塞排水管,导致土体排水不畅。为提高吹填土固结效率,采用自重沉淤排水与加负压排水固结相结合的方式在室内进行吹填土固结试验。试验第一阶段用排水管作为吹填土自重沉淤的竖向排水通道;第二阶段以装入中粗砂的排水管作吹填土排水通道,同时也是压力传递通道。试验监测到吹填土固结过程中不同位置孔隙水压力的变化,通过监测数据着重研究自重沉淤排水阶段吹填土的固结规律。借助渗流平衡方程确定吹填土在自重沉淤阶段孔隙水压力变化主要由排水管中水位、单位土面积控制,解释自重沉淤阶段孔隙水压力变化机理。同时,为了减小由于排水距离远近造成的固结不均,利用自重沉淤与加压固结结合的方法使吹填土达到较为理想的固结效果,将砂井设计理论与孔隙水压力变化曲线相结合确定排水管有效排水范围等效直径,为实际工程提供排水管间距的设计参数。

水土保持措施对土壤物理性状的影响——以黄土高原水土保持世界银行贷款项目区为例

通过对黄土高原水土保持世行贷款项目实施后土壤物理性状变化的分析,了解不同水土保持措施对土壤物理性状的影响。结果表明,水土保持措施的实施,使砂壤土的物理性粘粒逐渐增加,物理性砂粒相应减少,土壤容重降低,孔隙度增大,改善了土壤结构;同时以延河项目区人工种草为例,经计算消除降水影响后,所得水保措施对土壤含水量的影响量达2.35%。

考虑有效应力的钻屑量理论分析及试验研究

考虑深部开采条件下水平地应力作用不能忽略,引入有效应力,推导得到新钻屑量公式,分析给出了有效应力与钻屑量间关系,提出了通过有效应力判断钻屑量方法。在此基础上以典型阜新孙家湾矿突出危险煤层为例,利用自主研制的三维应力煤体钻屑量检测试验装置,改变轴压模拟垂直地应力、围压模拟水平地应力、孔隙压模拟瓦斯压力作用,进行了实验室尺度下钻屑法模拟试验,研究了有效应力、煤层深度、瓦斯压力对钻屑量影响规律。研究结果表明：钻屑量与有效应力呈线性递增关系,试验值略大于理论值,平均误差为7.9%,与前人结论一致,验证了新钻屑量公式有效性及三维应力煤体钻屑量检测试验装置可靠性;随着煤层埋藏深度增大,钻屑量越大,钻屑量与煤层深度呈线性递增规律,且钻屑量随钻孔深度增加呈先减小、后递增、最后缓慢递减规律,在钻孔深度12.5 cm处钻屑量最大,表明此处为应力集中区;钻屑量随瓦斯压力增加,呈指数函数递增规律,瓦斯压力越大,孔壁裂纹扩展越明显,说明瓦斯对煤体软化作用越显著。上述研究结论对该矿深部煤与瓦斯突出预测和防治具有重要参考价值。

采动围岩活动与工作面瓦斯涌出关系

结合平煤集团13矿己二12071工作面实际条件,对支架支护阻力、超前支承压力以及工作面瓦斯体积分数进行了实时监测,分析了采动过程与瓦斯涌出之间的关系.结果表明,随工作面矿压显现增大,瓦斯体积分数同步增大,压力降低,瓦斯体积分数随之下降.来压期间工作面前方瓦斯煤体"卸压增流",瓦斯涌出量增大;采空区冒落裂隙带内呈现含高瓦斯多孔多连通空间特性,来压过程对多孔多连通空间产生挤压或冲击和挤压综合作用,受冲(挤)扩散的高瓦斯气流向回采工作空间流动,导致工作面瓦斯体积分数增高.

4种景天属植物抗盐胁迫能力的差异

为辽宁(营口)沿海产业基地NaCl型盐碱地绿化工程筛选地被植物。分别用不同浓度NaCl溶液(0、50、100、2004、00 mmol/L)处理红八宝景天、粉八宝景天、景天三七、德国红景天幼苗,测定幼苗的植物量、叶片的水势、根系活力、质膜透性。结果表明,在盐胁迫下,上述4种景天鲜重、根系活力呈上升趋势,叶片水势呈下降趋势;相对电导率增加。在400 mmol/L盐胁迫下,景天三七与德国红景天耐盐性最强,其次粉八宝景天,红八宝景天耐盐性最弱。

不同水分条件下冬小麦旗叶和穗器官的PEPC活性及其与粒重和蛋白质含量的关系

为了明确小麦叶与非叶器官磷酸烯醇式丙酮酸羧化酶(PEPC)活性对水分胁迫的反应,在春不浇水和春浇2水两种水分条件下,对11个冬小麦品种旗叶、穗、颖片及籽粒的PEPC活性进行了测定,并分析了该酶活性与粒重和蛋白质含量的关系。结果表明,小麦不同品种和不同器官间PEPC活性存在明显差异,且受水分条件的影响。与正常供水处理(春浇2水)相比,水分胁迫处理(春不浇水)灌浆期旗叶PEPC活性下降,而颖片PEPC活性相对稳定,籽粒PEPC活性上升。水分胁迫使最终粒重降低、蛋白质含量增加。相关分析表明,灌浆期旗叶PEPC活性与粒重呈显著正相关(r=0.504*),颖片PEPC活性与籽粒蛋白质含量呈弱的正相关,籽粒PEPC活性与籽粒蛋白质含量呈极显著正相关(r=0.692**)。