Influencing factors and growth state classification of a natural Metasequoia population

By analyzing the importance of influencing factors and conducting a comparative study of the effects of different sorting algorithms, a new method is proposed that is suitable for classifying the growth state of a natural Metasequoia glyptostroboides Hu and W.C. Cheng population. We studied 2817 M. glyptostroboides trees over 100 years old and analyzed their growth state by measuring 15 factors from stumpage, site condition, and environmental data. The dimensionality of all factors were reduced using the random forest algorithm, and we classified the remaining factors using the following algorithms: random forest, back-propagation(BP) neural networks, and support vector machine(SVM). The applicability of each sorting algorithm was analyzed. When all the d factors are used for classification and modeling, the model's overall accuracy,kappa coefficient and test accuracy were 85.5%, 0.739 and 85.8%, respectively. By reducing the dimensionality of the factors using the random forest algorithm, 11 factors most strongly influenced the classifications of the growth state of the Metasequoia population: diameter at breast height,height, crown width, age from stumpage data; longitude,latitude, elevation, slope aspect, gradient and slope position from the site condition data; and the edge of the field from the environmental data. For classifying the Metasequoia population, the random forest algorithm has the highest overall accuracy at 87.2%, which is 3.4 and 2.3% higher than the BP neural networks and SVM algorithms,respectively. The SVM algorithm is superior to the random forest algorithm with respect to classifying the state of mortality. The combination of the random forest and SVM algorithms and their combined information can be used to classify and predict the growth state of this natural M.glyptostroboides population to provide a scientific basis for its effective protection.

Liquid State Undercoolability and Crystal Growth Kinetics of Ternary Ni-Cu-Sn Alloys

The liquid state undercoolability and crystal growth kinetics of ternary Ni-5%Cu-5%Sn and Ni-10%Cu-10%Sn alloys are investigated by the glass fluxing method. In these two alloys, experimental maximum undercoolings of 304 K （0.18TL ） and 286K （0.17TL ） are achieved and the dendritic growth velocities attain 39.8 and 25.1 m/s, respectively. The transition of morphology from coarse dendrite into equiaxed structure occurs and the grain size of the a （Ni） phase decreases remarkably when the undercooling increases. Both the lattice constant and microhardness increase obviously with the enhancement of undercooling. The enrichment of Cu and Sn solute contents reduces the dendritic growth velocity, while enhances the lattice constant and microhardness of a （Ni） phase.

Isothermal grain growth of reactive spray formed 7075 alloys in semi-solid state

The grain growth behavior in reactive spray formed 7075+2.91 vol percent TiCAl alloy was studied and compared with that of spray formed 7075 Al alloy at semi-solid state. Theeffects of in-situ TiC particles on the microstructure of spray formed 7075 Al alloy were alsoinvestigated. The specimens were heat-treated isothermally at various temperatures between thesolidus and liquidus of 7075 Al alloy for times in the range of 10-60 min, then quenched in water.The microstructure of reheated specimens was characterized using scanning electron microscopy andoptical microscopy. The grain size was measured using a mean linear intercept method. Results showthat the in-situ TiC particles can effectively retard grain growth and refine the grain at a limitedsize. The grain growth exponent in Arrhenius equation increases from 2 to 3, which indicates thatthe in-situ TiC particles have the significant pinning effect on grain coarsening in the semi-solidstate.

Preliminaries for a New Mathematical Framework for Modelling Tumour Growth Using Stress State Decomposition Technique

The main goal of the present paper is to present a mathematical framework for modelling tumour growth based on stress state decomposition technique (SSDT). This is a straightforward extension of the model for multi-phase nonsaturated soil consolidation with pollutant transport presented by the authors and may be regarded as an alternative to classical frameworks based on TCAT theory. In this preliminary work, the Representative Volume Element (RVE) for tumour is proposed along with its comparison with the corresponding one for soils modelling developed formerly by the authors. Equations standing for tumour phase are flawlessly brought into correspondence with those of gaseous phase in the soil problem showing that a similar task may be carried out for the remainders phases taking part in both RVEs. Furthermore, stresses induced by nonlinear saturation and permeability dependence on suction for soil interstitial fluids transport finds its counterpart on the contact between the cancer cell membrane and interstitial fluids rendering a higher primary variables coupling degree than what was attained in TCAT theory. From these preliminaries assessments, it may be put forward that likewise the stress state decomposition procedure stands for an alternative for modelling multi-phase nonsaturated soil consolidation with pollutant transport;it does for modelling cancer as well.

Declining Vegetation Growth Rates in the Eastern United States from 2000 to 2010

Negative trends in the monthly MODerate resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index (EVI) time-series were found to be widespread in natural (non-cropland) ecosystems of the eastern United Statesfrom 2000 to 2010. Four sub-regions were detected with significant declines in summed growing season (May-September) EVI, namely theUpper Great Lakes, the Southern Appalachian, the Mid-Atlantic, and the southeastern Coastal Plain forests ecosystems. More than 20% of the undeveloped ecosystem areas in the four sub-regions with significant negative EVI growing season trends were classified as forested land cover over the entire study period. We detected relationships between annual temperature and precipitation patterns and negative forest EVI trends across these regions. Change patterns in both the climate moisture index (CMI) and growing degree days (GDD) were associated with declining forest EVI growing season trends. We conclude that temperature warming-induced change and variability of precipitation at local and regional scales may have altered the growth trends of large forested areas of the easternUnited Statesover the past decade.

The Existence of Ground State Solutions for Schrödinger-Kirchhoff Equations Involving the Potential without a Positive Lower Bound

In this paper, we study the following Schrödinger-Kirchhoff equation where V(x) ≥ 0 and vanishes on an open set of R2 and f has critical exponential growth. By using a version of Trudinger-Moser inequality and variational methods, we obtain the existence of ground state solutions for this problem.

Crack growth time dependence analysis of granite under compressive-shear stresses state

The curves of crack relative length lib and crack growth time t of granite were gained under compressive stresses state according to subcritical crack growth parameters and crack stability growth equation by double-torsion constant displacement load relaxa- tion method.The relations between crack relative length and the crack growth time were discussed under different stresses and different crack lengths.The results show that there is a turning point on curve of crack relative length//b and crack growth time of granite.The slope of curve is small when crack relative length is less than the vertical coordinate of the point,and crack grows stably in this case.Cracks grow,encounter and integrate catastro- phically when crack relative length is more than the vertical coordinate of the point,and there is not a gradual stage from crack stability growth to crack instability growth,i.e.rock mass instability is sudden.The curves of crack relative length lib and crack growth time t of granite move to right with decrease of stress σ_1 or crack length a,which implies that limit time increases consequently.The results correspond to practicality.

Regulatory effect of vascular endothelial growth factor on blood spinal cord barrier in presyrinx state of experimental syringomyelia

BACKGROUND： Vascular endothelial growth factor （VEGF） is able to regulate blood spinal cord barrier function as well as influence neovascularization and cause edema. OBJECTIVE： Through establishment of a rabbit model of syringomyelia, to explore the correlation between VEGF protein and mRNA expressions and function of blood spinal cord barrier and edema degree of spinal cord in presyrinx state. DESIGN, TIME AND SETTING： Randomized controlled animal study was performed in the Tumor Institute of the Fourth Hospital, Hebei Medical University from January to June 2007. MATERIALS： Atotal of 0.6 mL Kaolin solution （250 g/L, 37℃） was injected into the cisterna magna of 40 rabbits in the kaolin group to establish syringomyelia models. Goat anti-rabbit VEGF monoclonal antibody was provided by DIACLONE Company, USA; RT-PCR related reagents were provided by Huamei Bioengineering Co., Ltd., Beijing. METHODS： Sixty Chinese white rabbits were divided randomly into two groups： Kaolin group （n = 40） and control group （n = 20）. Physiological saline （0.6 mL at 37℃） was injected in rabbits of control group. On days 1,3, 7, 14 and 21 after kaolin injection, cervical cords samples were harvested after sacrifice of animal. MAIN OUTCOME MEASURES： VEGF protein and mRNA expressions were detected by immunohistochemistry and RT-PCR on days 1, 3, 7, 14, and 21 after kaolin injection. A quantitative analysis of blood spinal cord barrier function was performed by Evans blue technique. Water content of the spinal cord was measured by dry-wet weight technique. The correlation between the expression of VEGF protein and mRNA and the function of blood spinal cord barrier in the upper cervical cord of the presyrinx state was analyzed by linear correlation analysis. RESULTS： The water content and Evans blue content increased in the kaolin group on days 1 and 3 postoperatively compared with the control group （F = 7.387, 61.35, P 〈 0.05, 0.01）, and reached a peak on day 7 （F = 135.94, 528.35, P 〈 0.01）. They declined slowly to day 21 postoperatively, but both contents were still higher than the control group （F = 11.51, 58.63, P 〈 0.01）. VEGF protein expression increased on day 1, and stronger positive expression was seen on days 3, 7 and 14. It decreased on day 21. VEGF protein expression was higher than the control group at each time point （F = 137.4-468.5, P 〈 0.01 ）. VEGF mRNA expression showed the same pattern in the cervical cord at different time points. By statistical analysis, the expression of VEGF protein and mRNA had a significantly positive correlation with the structural and functional changes of the blood spinal cord barrier in the presyrinx state （r = 0.604-0.979, P 〈 0.05）. CONCLUSION： In the presyrinx state of syringomyelia, the expressions of VEGF protein and mRNA can influence the structure and function of the blood spinal cord barrier and play an important role in the formation and development of spinal cord edema and syringomyelia.

火针联合低压无针瘢痕内注射复方倍他米松治疗瘢痕疙瘩疗效及对生长因子水平、瘢痕状态的影响

目的观察火针联合低压无针瘢痕内注射复方倍他米松治疗瘢痕疙瘩的效果及对生长因子水平、瘢痕状态的影响。方法选取2021年1月—2022年2月来我院就诊100例瘢痕疙瘩患者,随机分为对照组、治疗组,每组各50例,对照组采用低压无针瘢痕内注射复方倍他米松,治疗组在对照组基础上加火针治疗,对比两组疗效、生长因子水平、瘢痕状态。结果治疗组治疗后总有效率较对照组为高(P<0.05);治疗组治疗后细胞生长因子β1(TGF-β1)、血小板源生长因子(PDGF)、表皮细胞生长因子(EGF)指标水平均较对照组为低,成纤维细胞生长因子(FGF)指标水平较对照组为高(P<0.05);观察组治疗后瘢痕状态评分均较对照组低(P<0.05)。结论火针联合低压无针瘢痕内注射复方倍他米松治疗瘢痕疙瘩疗效明显,可调节生长因子水平,还能改善瘢痕状态,促进其恢复,值得推广。

Generalized electro-biothermo-fluidic and dynamicalmodeling of cancer growth: state-feedback controlled cesium therapy approach

This paper develops a generalized dynamical model to describe the interactive dynamics between normal cells, tumor cells, immune cells, drug therapy, electromagnetic field of the human cells, extracellular heat and fluid transfer, and intercellular fractional mass of Oxygen, cell acidity and Pancreatin enzyme. The overall dynamics stability, controllability and observability have been investigated. Moreover, Cesium therapy is considered as a control input to the 11-dimensional dynamics using state-feedback controlled system and pole placement technique. This approach is found to be effective in driving the desired rate of tumor cell kill and converging the system to healthy equilibrium state. Furthermore, the ranges of the system dynamics parameters which lead to instability and growth of tumor cells have been identified. Finally, simulation results are demonstrated to verify the effectiveness of the applied approach which can be implemented successfully to cancer patients.

基于改进YOLOv5的田间大豆花朵生长状态识别方法研究

为判断大豆开花时期落花情况,对田间大豆花朵在花蕾、半开、全开、凋落四类生长状态下进行精准检测。基于YOLOv5检测模型,对主干Bottleneck CSP结构进行修改,减少模块数量来保留更多浅层特征,增强特征表达能力,在骨干网络中引入CA注意机制,以获得位置信息,协助模型更加准确地识别,并修改锚箱尺寸提高小目标花蕾精准识别,在自建的田间大豆花朵不同生长状态数据集上进行改进YOLOv5算法对比试验。结果表明:大豆开花时期花朵不同生长状态识别模型准确率达到93.4%,召回率达到91.4%,对比原模型准确率、召回率分别提高0.8%和2.1%。

国有企业稳增长:跨周期调节机理与实施路径

稳增长是国有企业的核心功能之一。文章从跨周期调节视角论述了国有企业稳增长的内在机理、经验事实与实施路径,研究发现:国有企业稳增长要坚持发挥国家发展规划的战略导向作用,以做实做强做优实体经济为着力点,以促进经济增长方式转变、结构优化、动力转换为重点,坚持稳中求进方法论,促进高质量发展;国有企业在基础设施、科技创新、区域平衡发展、收入分配、社会责任等领域的跨周期调节表现较为突出;新发展阶段,国有企业稳增长的实施路径包括:拓展有效投资空间和领域、优化国有资本空间行业布局、发挥价格调节机制在降低宏观经济运行成本中的基础性作用、提供更多高质量的基本公共产品和服务。

蚯蚓在水产饲料中的应用研究

文章综述了蚯蚓的生物学特性、营养成分及其在水产饲料中的应用研究现状,简述了蚯蚓粉和蚯蚓鲜虫等多种蚯蚓产品在不同水产动物中的应用研究进展,阐明了在水产动物饲料中添加适宜水平的蚯蚓产品对其生长和健康等具有促进作用,提出蚯蚓水产饲料化进程中存在的问题,以期为蚯蚓水产饲料的开发及生产提供参考资料。

基于系统状态特征分析的软件可靠性评估方法

针对以指挥信息系统为典型的复杂任务型软件试验鉴定领域中可靠性评估问题,在总结现有评价方法的基础上,提出了基于系统状态特征分析的可靠性评估方法。首先,从软件使命任务的角度解析系统的状态特征,设计充分覆盖系统典型应用样式及状态特征的测试用例,通过定义“使用强度”,替代原有可靠性评价中“持续时间”指标,在此基础上收集可靠性失效数据,并给出软件可靠性增长模型(software reliability and growth model,SRGM)参数估计及可靠性评估过程。最后通过某任务型软件的可靠性评估试验,验证提出方法在工程实践中的可行性,同时给出了工程示例中收集的真实失效数据和SRGM参数估计结果,确保研究成果真实性和可复现性。

襄阳楚史的成长期

襄阳楚史分为楚族形成、成长、强盛、衰落和涅槃五个时期。成长期上承楚族形成期,下讫强盛期。其上限为西周初的熊绎,下限至春秋初的熊眴,大约286年的历史。成长期的楚国面对西周处在劣势中,周强楚弱,楚只有在困顿中前行,砥砺中奋进,其发展脉状大致上为:起—落—起—落—起。

乳酸胁迫对Pichia kudriavzevii固态发酵特性的影响

浓香型白酒糟醅富含乳酸,库德毕赤酵母(Pichia kudriavzevii)为其中优势酵母。为探究乳酸对浓香型白酒优势酵母固态发酵特性的影响,在不同浓度的乳酸胁迫下,从碳源消耗、生长因子利用、高温耐受性以及主要代谢产物生成等方面,考查P.kudriavzevii(编号:PY1)的生长代谢转变。结果表明,乳酸胁迫对P.kudriavzevii菌落与细胞形态无明显影响,对细胞生长有一定抑制,且这种可逆抑制可被氨基酸及维生素削弱,当培养温度超过44℃,乳酸对菌株生长的影响逐渐让位于温度。代谢方面,乳酸可提高葡萄糖、半乳糖、麦芽糖、果糖和蔗糖利用率;增加乙醇和酯类生成量、降低高级醇生成量。综上,乳酸可通过影响酵母生长代谢影响浓香型白酒风味形成,可作为浓香型白酒发酵调控因子。

产香酵母菌丸麦曲固态发酵系统构建及其生长动力学研究

该研究设计了双层浅盘式生物反应器,以丸麦(去皮小麦)为培养基质,不同产香酵母为菌种,搭建丸麦曲固态发酵系统,并根据Logistic模型建立菌体生长动力学模型。结果表明,季也蒙毕赤酵母(Meyerozyma guilliermondii)、异常威克汉姆酵母(Wickerhamomyces anomalus)、马尔克斯克鲁维酵母(Kluyveromyces marxianus)、葡萄汁有孢汉逊酵母(Hanseniaspora uvarum)固态发酵26 h,丸麦曲中酵母活菌数均达4×10^(9) CFU/g以上。成功建立了4种产香酵母的Logistic模型(R2>0.96,P值均<0.001),模型拟合值与试验值间的相对误差均<3%,说明该模型能较好地反映4种产香酵母在丸麦上的生长特征。

菜籽粕混合发酵饲料替代豆粕对生长猪生长性能、养分表观消化率以及血清生化和抗氧化指标的影响

本试验旨在研究菜籽粕混合发酵饲料替代豆粕对生长猪生长性能、养分表观消化率以及血清生化和抗氧化指标的影响。试验选用70%菜籽粕、15%玉米皮和15%麸皮混合作为发酵原料,筛选菌种后选择添加酵母菌、罗伊氏乳杆菌(Lactobacillus reuteri)和中性蛋白酶进行发酵。优化发酵条件后将条件控制为含水量55%、发酵温度30℃、发酵时间60 h,干燥制得发酵饲料。在饲喂试验中,选取平均体重为(39.3±5.3)kg的“杜×长×大”三元杂交生长猪72头,随机分为3组,每组3个重复,每个重复8头猪(公母各占1/2)。对照组(CON组)饲喂基础饲粮,未发酵组(RMD组)饲喂用15%未发酵菜籽粕混合饲料替代基础饲粮中豆粕、玉米和麸皮的饲粮,发酵组(FRMD组)饲喂用15%菜籽粕混合发酵饲料替代基础饲粮中豆粕、玉米和麸皮的饲粮。试验期28 d。结果表明:1)混合发酵显著提高了菜籽粕混合饲料的粗蛋白质(CP)和三氯乙酸酸溶蛋白(TCA-N)含量(P<0.05),显著降低了硫代葡萄糖苷、植酸和单宁含量(P<0.05)。2)饲养试验结果表明,3组生长猪生长性能无显著差异(P>0.05);FRMD组总磷表观消化率要显著高于RMD组(P<0.05);与CON组相比,RMD组血清尿素氮(UN)含量有所提高(P>0.05),而FRMD组血清UN含量无显著差异(P>0.05);与RMD组相比,FRMD组血清谷胱甘肽过氧化物酶(GSH-Px)活性显著降低(P<0.05)。由此可见,混合发酵可提高菜籽粕的营养价值,并且菜籽粕在混合发酵后可部分替代生长猪饲粮中的豆粕。

具有能量临界增长的非线性薛定谔方程驻波的存在性

提出一类具有能量临界增长的非线性薛定谔方程,满足非线性项均为聚焦状态。通过解决一个在给定的条件下变分问题,得到该类方程基态驻波解的存在性。结果表明,当空间维数大于4时,基态驻波解对于所有的正频率都是存在的。