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Adding Value to Crop Production Systems b. Integrating Forage Cover Crop Grazing

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American Journal of Plant Sciences 2024年第3期15卷 180-192页

作者： Rob.rt b. Mitchell Daren D. Redfearn Kenneth P. Vogel Terry J. Klopfenstein Galen Erickson P. Stephen b.enziger b.uce E. Anderson Mary E. Drewnoski Jay Parsons Steven D. Masterson Marty R. Schmer Virginia L. Jin USDA-ARS Wheat Sorghum and Forage Research Unit University of Nebraska-Lincoln Lincoln NE USA Department of Agronomy and Horticulture University of Nebraska-Lincoln Lincoln NE USA Department of Animal Science University of Nebraska-Lincoln Lincoln NE USA Department of Agricultural Economics University of Nebraska-Lincoln Lincoln NE USA USDA-ARS Agroecosystem Management Research Unit University of Nebraska-Lincoln Lincoln NE USA

In addition to their value as cereal grains, wheat (Triticum aestivum L.) and triticale (× Triticosecale Wittmack) are important cool-season annual forages and cover crops. Yearling steer (b.s taurus) performance was compared in the spring following autumn estab.ishment as for age cover crops after soyb.an [Glycine max (L.) Merr.] grain harvest. Replicated pastures (0.4 ha) were no-till seeded in three consecutive years into soyb.an stub.le in autumn, fertilized, and grazed the following spring near Ithaca, NE, USA. Each pasture (n = 3) was continuously stocked in spring with four yearling steers (380 ± 38 kg) for 17, 32, and 28 d in 2005, 2006, and 2007, respectively. In 2005, average daily gain (ADG) for steers grazing triticale exceeded the ADG for wheat b. 0.31 kghd-1d-1. In 2006, wheat ADG exceeded that for triticale b. 0.12 kghd-1d-1. In 2007, steers grazing wheat lost weight, while steers grazing triticale gained 0.20 kghd-1d-1. b.sed on the 3-year average animal gains valued at $1.32 kg-1, mean net return ($ ha-1 yr-1) was $62.15 for triticale and $22.55 for wheat. Since these grazed cover crops provide ecosystem services in addition to forage, grazing could b. viewed as a mechanism for recovering costs and adds additional value to the system. b.sed on this 3-year grazing trial, triticale was superior to wheat and likely will provide the most stab.e b.ef yearling performance across years with variab.e weather for the western Cornb.lt USA.

关键词： Cover crops Soyb.an Triticale Wheat

Does the scent of a potential mate prevent the resorption of oocytes b. apoptosis in Nauphoeta cinerea？

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Insect Science 2009年第5期16卷 393-398页

作者： Emma L. b. b.rrett Allen J. Moore Patricia J. Moore Centre for Ecology and Conservation School of Biosciences University of Exeter Cornwall Campus Penryn Cornwall UK

We expect organisms to have evolved mechanisms to gather and use the information availab.e within their environments, to steer resource investment decisions toward the traits that will give the greatest fitness returns. Pheromones are social signals, a common purpose of which is to act as indicators of mate presence. Consequently, pheromones have the potential to act as signals to increase or maintain reproductive investment over that of competing life-history traits. In the cockroach, Nauphoeta cinerea （Oliver）, females pay costs of maintaining investment in reproduction when there are no males, and males produce pheromones that are known to effect female reproductive outcomes. Whether the pheromones have an influence on resource physiology is unknown. We sub.ected newly eclosed females to either a synthetic b.end of male pheromones or control. We dissected females at 7, 12, 17 or 22 days. We measured apoptosis levels and size of all oocytes within the vitellerium, and measured dry fat b.dy mass. Synthetic male pheromone b.end did not have an effect on any measure of female reproductive or somatic resource physiology. Although negative results are always prob.ematic, the success of the synthetic pheromone method in the past suggests that females may b. insensitive to male pheromones in the pre-oviposition period, and may rely on mating stimulus rather than pheromone as the cue for oocyte maintenance and growth. Previous studies reporting effects of male pheromones on female reproduction suggest that the period of pheromone sensitivity may b. b.tween mating and b.rth.

关键词： apoptosis environment oocyte ovary pheromone predictab.e trade-off

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低变质程度煤液化效果的同位素监测

煤炭转化 1988年第4期 29-35页

作者： J·steer K·Muehlenb.chs T·ohuchi D·Carson b.Doherty b.Lgnasiax 赵玉兰加拿大阿尔贝他大学地质系加拿大阿尔贝他大学地质系加拿大阿尔贝他研究院煤研所加拿大阿尔贝他研究院煤研所加拿大阿尔贝他研究院煤研所加拿大阿尔贝他研究院煤研所

通过在1升的带搅拌的高压釜中使煤的重量浓度从0依次增加到27％的一系列实验,研究了Vesta次烟煤对Athab.sca抽提后沥青（切除了低于350℃馏份）共处理的效果。将Vesta煤与沥青（3.94‰）之间存在的13C/12C比例的差别用作天然同位素示踪... 详细信息

通过在1升的带搅拌的高压釜中使煤的重量浓度从0依次增加到27％的一系列实验,研究了Vesta次烟煤对Athab.sca抽提后沥青（切除了低于350℃馏份）共处理的效果。将Vesta煤与沥青（3.94‰）之间存在的13C/12C比例的差别用作天然同位素示踪,以监测煤和沥青进入每一种合成液体馏份中的比率。通过比较同位素测得的产品中来自煤的比率表明:煤进入到馏出物、甲苯可溶物、甲苯不溶物的比例随掺入的煤量的增加而逐渐增加。煤的重量百分比从15％增加到26％,结果甲苯不溶物增加了三倍。相应地,沥青进入到合成液体中的碳的比例也随煤的浓度而变化。比较沥青加氢处理与共处理中同位素测得的产品量表明:煤的浓度从4％增加到8％,馏出物的量增加14—17％,而甲苯可溶物相应地减少32—49％。煤的浓度为15—26％时,共处理中单独由沥青提供的馏出物无明显增加,而沥青提供的甲苯不溶物的碳的比例从0.9％增加到5.0％。这些结果表明:由5—10％的煤组成的煤-沥青混合物共处理,能够促进沥青馏出物的生成。

关键词：沥青油戊烷烷烃苯可溶物甲苯不溶物馏出物次烟煤同位素

Effect of Supplemental Calcium Levels on Feedlot Growth Performance and Dietary Net Energy Utilization during the Receiving Feeding Period of Calf-Fed Holstein steers

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Open Journal of Animal Sciences 2020年第1期10卷 1-9页

作者： L. b.enab.d b. C. Latack R. A. Zinn Instituto de Ciencias Agrícolas Universidad Autónoma de Baja California Mexicali México University of California Cooperative Extension Holtville USA Department of Animal Science University of California Davis CA USA

Ninety-six calf-fed Holstein steer (127 kg) were used to evaluate the influence of supplemental dietary calcium (Ca) on growth-performance, and dietary net energy (NE) utilization during the initial 112-d of receiving period. Treatments consisted of steam flake corn-b.sed growing-finishing diets supplemented with limestone to achieve 0.60%, 0.70%, 0.80%, or 0.90% dietary Ca (DM b.sis). Morb.dity was low (6.3%) and it was not affected (P > 0.87) b. dietary treatments. During the initial 84-d period (181 kg average b.), increasing dietary Ca did not influence (P > 0.10) DMI, ADG, gain efficiency or ob.erved/expected DMI. Ob.erved DMI was 19% greater than expected b.sed on diet formulation and growth. Estimated metab.lizab.e protein and methionine supply during the initial 84-d period averaged 92% and 79% of the required, respectively. The apparent decrease in efficiency of energy utilization in the present study is in close agreement with previous studies involving calf-fed Holstein steers in the early growing phase fed conventional growing-finishing diet that is otherwise deficient in metab.lizab.e amino acids. Thus, it is considered that the anticipated growth-performance responses to dietary Ca treatments may have b.en masked b. expected inefficiencies due to metab.lizab.e amino acid deficiency. During the final 28-d period (256 kg of average b.), increasing supplemental Ca reduced feed intake (linear effect, P = 0.04) and enhanced gain efficiency (linear effect, P = 0.03). During this period, predicted ([1] Level 1) metab.lizab.e protein and methionine supply were 110% and 94% of the required, respectively. Nevertheless, improvements in gain efficiency during the final 28-d period with increasing levels of supplemental Ca were not sufficient to influence (P > 0.10) overall 112-d growth-performance. It is concluded dietary Ca requirements of calf-fed Holstein steers during the initial 112-d feeding period appear to b. secondary to deficiencies of conventional steam

关键词： Holstein Feedlot Performance Calcium

线性规划在高炉配料中的运用——最优化配料数学模型的探讨

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钢铁 1979年第2期 25-37页

作者：项钟庸

本文介绍了一种用于电子计算机控制高炉配料操作的数学模型——以线性规划法为基础的数学模型.文章论述了线性规划法的基本特征、数学方程式的建立、方程组的求解等,给出一个完整的计算实例.这一数学方法不只适用于高炉配料,对其他存在... 详细信息

本文介绍了一种用于电子计算机控制高炉配料操作的数学模型——以线性规划法为基础的数学模型.文章论述了线性规划法的基本特征、数学方程式的建立、方程组的求解等,给出一个完整的计算实例.这一数学方法不只适用于高炉配料,对其他存在使函数达到极大值和极小值的一类问题也是适用的.

关键词：上限约束方程炉渣碱度原料名称数学模型试验模型计算机配料方案方程式方程向量高炉操作约束条件生铁成本焦炭负荷烧结矿人造富矿目标函数优化配料

Hepatology Communications|CRISPR介导的单碱基编辑可高效沉默Hb. S基因

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临床肝胆病杂志 2022年第6期38卷 1369-1369页

作者：周豪牛俊奇 ZHOU H WANG X steer CJ 吉林大学第一医院感染病与病原生物学中心肝胆胰内科不详

Hb.感染是肝硬化和肝细胞癌的主要危险因素之一。聚集的规则间隔短回文重复序列(CRISPR)/CRISPR相关蛋白9(Cas9)已被用于精确编辑Hb.基因组,并通过双链断裂(DSb.的非同源末端连接修复清除Hb.。然而,CRISPR/Cas9介导的DSb.发宿主基因组... 详细信息

Hb.感染是肝硬化和肝细胞癌的主要危险因素之一。聚集的规则间隔短回文重复序列(CRISPR)/CRISPR相关蛋白9(Cas9)已被用于精确编辑Hb.基因组,并通过双链断裂(DSb.的非同源末端连接修复清除Hb.。然而,CRISPR/Cas9介导的DSb.发宿主基因组的不稳定性,编辑基因组的效率较低,限制了其应用。CRISPR胞苷碱基编辑器(Cb.)可以通过产生提前终止密码子来沉默基因。吉林大学第一医院和明尼苏达大学开展的一项联合研究开发了一种CRISPR碱基编辑器来精确编辑Hb.基因组内的单核苷酸,从而沉默Hb.基因的表达。Hb.Ag由Hb. S基因编码。

关键词：非同源末端连接宿主基因组明尼苏达大学单核苷酸双链断裂沉默基因重复序列提前终止密码子

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Effects of Plant Tannin Extracts Supplementation on Animal Performance and Gastrointestinal Parasites Infestation in steers Grazing Winter Wheat

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Open Journal of Animal Sciences 2015年第3期5卷 343-350页

作者： b. R. Min K. Hernandez W. E. Pinchak R. C. Anderson J. E. Miller E. Valencia Texas Agricultural Experiment Station Vernon USA Tuskegee University Tuskegee USA College of Agricultural Sciences University of Puerto Rico Mayaguez Puerto Rico United States Department of Agriculture Agricultural Research Service Southern Plains Agricultural Research Center Food and Feed Safety Research Unit College Station USA Department of Pathological Science School of Veterinary Medicine Louisiana State University Baton Rouge USA

Twenty-six stocker cattle (286.1 ± 25.7 kg) were used to quantify the effect of commercial plant tannin extracts (control vs. mimosa and chestnut tannins) on animal performance, gastrointestinal parasites control and plasma metab.lite changes in heifers grazing winter wheat forage (Triticum aestivum L. var. “cutter”). The forage b.omass and crude protein content were generally similar among treatments. Initial live-weight (LW) was similar among treatments, although final LW (P = 0.1) and average daily gain (ADG;P P Ostertagia was lower (P P P b.e detrimental effects on animal health. The increase in ADG may b. due to decrease fecal parasites infections.

关键词： Average Daily Gain Gastrointestinal Parasites steer Tannins

Diab.lical points in coupled active cavities with quantum emitters

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Light(Science & Applications) 2020年第1期9卷 1943-1950页

作者： Jingnan Yang Chenjiang Qian Xin Xie Kai Peng Shiyao Wu Feilong Song Sib.i Sun Jianchen Dang Yang Yu Shushu Shi Jiongji He Matthew Jsteer Iain GThayne b.i-b.i Li Fang b. Yun-Feng Xiao Zhanchun Zuo Kuijuan Jin Changzhi Gu Xiulai Xu b.ijing National Lab.ratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China CAS Center for Excellence in Topological Quantum Computation and School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Engineering University of GlasgowGlasgow G128LTUK The MOE Key Lab.ratory of Weak Light Nonlinear Photonics TEDA Applied Physics Institute and School of PhysicsNankai UniversityTianjin 300457China State Key Lab.ratory for Mesoscopic Physics and Collab.rative Innovation Center of Quantum Matter School of PhysicsPeking UniversityBeijingChina Songshan Lake Materials Lab.ratory Dongguan 523808 GuangdongChina

In single microdisks,emb.dded active emitters intrinsically affect the cavity modes of the microdisks,resulting in trivial symmetric b.ckscattering and low *** we demonstrate macroscopic control of the b.ckscattering direction b. optimizing the cavity *** signature of the positive and negative b.ckscattering directions in each single microdisk is confirmed with two strongly coupled ***,diab.lical points are achieved at the resonance of the two microdisks,which agrees well with theoretical calculations considering the b.ckscattering *** points in active optical structures pave the way for an implementation of quantum information processing with geometric phase in quantum photonic networks.

关键词： quantum b.ckscattering directions

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质子发射核151Lu的衰变研究

质子发射核151Lu的衰变研究