mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
Bacteriophage secondary infection

Phages are credited with having been first described in what we now, officially, are commemorating as the 100~(th) anniversary of their discovery. Those one-hundred years of phage history have not been lacking in excitement, controversy, and occasional convolution. One such complication is the concept of secondary infection, which can take on multiple forms with myriad consequences. The terms secondary infection and secondary adsorption, for example, can be used almost synonymously to describe virion interaction with already phage-infected bacteria, and which can result in what are described as superinfection exclusion or superinfection immunity. The phrase secondary infection also may be used equivalently to superinfection or coinfection, with each of these terms borrowed from medical microbiology, and can result in genetic exchange between phages, phage-on-phage parasitism, and various partial reductions in phage productivity that have been termed mutual exclusion, partial exclusion, or the depressor effect. Alternatively, and drawing from epidemiology, secondary infection has been used to describe phage population growth as that can occur during active phage therapy as well as upon phage contamination of industrial ferments. Here primary infections represent initial bacterial population exposure to phages while consequent phage replication can lead to additional, that is, secondary infections of what otherwise are not yet phage-infected bacteria. Here I explore the varying meanings and resultant ambiguity that has been associated with the term secondary infection. I suggest in particular that secondary infection, as distinctly different phenomena, can in multiple ways influence the success of phage-mediated biocontrol of bacteria, also known as, phage therapy.
Reorganization of spinal neural circuitry and functional recovery after spinal cord injury

The ability of the adult central nervous system to reorganize its circuits over time is the key to understand the functional improvement in subjects with spinal cord injury (SCI). Adaptive changes within spared neuronal circuits may occur at cortical, brainstem, or spinal cord level, both above and below a spinal lesion (Bareyre et al., 2004). At each level the reorganization is a very dynamic process, and its degree is highly variable, depending on several factors, including the age of the subject when SCI has occurred and the rehabilitative therapy.
Antagonizing amyloid-β/calcium-sensing receptor signaling in human astrocytes and neurons: a key to halt Alzheimer's disease progression?

Astrocytes' roles in late-onset Alzheimer's disease (LOAD) promotion are important, since they survive soluble or fibrillar amyloid-β peptides (Aβs) neurotoxic effects, undergo alterations of intracellular and intercellular Ca~(2+) signaling and gliotransmitters release via the Aβ/α7-nAChR (α7-nicotinic acetylcholine receptor) signaling, and overproduce/oversecrete newly synthesized Aβ_(42) oligomers, NO, and VEGF-A via the Aβ/CaSR (calcium-sensing receptor) signaling. Recently, it was suggested that the NMDAR (N-methyl-D-aspartate receptor) inhibitor nitromemantine would block the synapse-destroying effects of Aβ/α7-nAChR signaling. Yet, this and the progressive extracellular accrual and spreading of Aβ_(42) oligomers would be stopped well upstream by NPS 2143, an allosteric CaSR antagonist (calcilytic).
Mapping and Assessing Typhoon-induced Forest Disturbance in Changbai Mountain National Nature Reserve Using Time Series Landsat Imagery

Monitoring forest disturbances is important for understanding changes in ecosystems. The 1986 Typhoon Vera was a serious disturbance that severely impacted the forest ecosystems of Changbai Mountain National Nature Reserve. Although the typhoon disturbance occurred more than two decades ago, the effects of the typhoon still remain within the study area. Few studies have focused on mapping and assessing disturbances across broad spatial and temporal scales. For this study, we first generated a map of forest composition prior to the typhoon disturbance, which served as a baseline data for the extraction of disturbed area. Then, the Disturbance Index (DI) method was tested for mapping the extent and magnitude of disturbance in the study area by applying a Tasseled Cap transformation to the Landsat imagery. The Landsat-based DI method estimated that an area of 13,764.78 ha of forest was disturbed by the typhoon. Based on visual assessments, these results correspond closely with the reference map derived from ground surveys. These results also revealed the influence of local topographic features on the distribution of windthrow areas. Windthrow areas were more pronounced in areas with elevations ranging from 1,000 to 2,000 m, slopes of less than 10 degrees, and southwestern to northwestern aspects. In addition, the relatively long (25 years) post-typhoon recovery period assessed by this study provided a more comprehensive analysis of the dynamics of forest recovery processes over time. Windthrow areas did not recover immediately after the typhoon, likely due to forest management practices enacted at the time. So far, forest recovery has proceeded more rapidly at elevations below 1,400 m, particularly on western slopes within the study area. Finally, a time series of DI values within the study period suggests a secondary disturbance may have occurred between 2000 and 2001.
Blow-up Dynamics of L~2 Solutions for the Davey–Stewartson System

We study the blow-up solutions for the Davey–Stewartson system (D–S system, for short) in L_x~2(R~2). First, we give the nonlinear profile decomposition of solutions for the D–S system. Then, we prove the existence of minimal mass blow-up solutions. Finally, by using the characteristic of minimal mass blow-up solutions, we obtain the limiting profile and a precisely mass concentration of L~2 blow-up solutions for the D–S system.
Long-term Analysis of Degenerate Parabolic Equations in R~N

Longtime behavior of degenerate equations with the nonlinearity of polynomial growth of arbitrary order on the whole space R~N is considered. By using ?-trajectories methods, we proved that weak solutions generated by degenerate equations possess an (L_U~2 (R~N), L_(loc)~2(R~N))-global attractor. Moreover, the upper bounds of the Kolmogorov ε-entropy for such global attractor are also obtained.
非气腹悬吊式单一部位切口腹腔镜胰体尾及脾切除治疗胰尾>9 cm良性肿瘤1例报告

非气腹悬吊式单孔腹腔镜手术是将非气腹悬吊式腹腔镜手术、单孔腹腔镜手术和开腹手术三者优点结合而形成的微创手术。1999年Hellinge首次报道非气腹悬吊式单孔腹腔镜小肠造瘘术,而后该项技术相继在泌尿外科、妇科得到应用。2014年9月,我科收治1例胰尾良性肿瘤,行非气腹悬吊式单一部位腹腔镜远端胰腺切除术。现结合相关文献分析报道如下。
经皮内镜下腰椎间盘髓核切除术的应用进展

开放手术治疗腰椎间盘突出症创伤大、恢复慢、费用高, 随着新技术及新材料的发展, 在保证 /提高疗效的前提下, 先后出现经皮椎间盘切吸术、经皮激光汽化椎间盘减压术、经皮低温等离子射频消融髓核成形术、臭氧髓核消融术、胶原酶溶解术、显微内镜椎间盘切除术 (micro endoscopic discectomy, MED)等, 但以上方法适应证窄, 疗效不确定, 临床应用不广泛。经皮内镜下腰椎间盘髓核切除术(percutaneous endoscopic lumbar discectomy, PELD)在局部麻醉下完成手术操作, 术中创伤小、出血少、视野清晰, 具有安全、对脊柱的稳定性破坏小、操作时不易损伤神经、术后瘢痕组织极少造成椎管及神经的粘连、治疗失败行后路补救手术较为容易等优点, 适应证相对较广, 可拓展性强。近年来, PELD被广泛应用于腰椎退变性疾病的治疗, 本文就其发展史、优势、临床应用、并发症做一综述。
糖原合成酶激酶3β对卵巢癌顺铂耐药性的影响及其机制研究

目的:探讨糖原合成酶激酶3β(glycogen synthase kinase,GSK-3β)对卵巢癌顺铂耐药性的影响及机制。方法:运用氯化锂(lithium chloride,Li Cl)增加失活性GSK-3β即p-GSK-3β表达,MTT法筛选合适的Li Cl浓度和作用时间并检测顺铂的半数抑制浓度,流式细胞仪检测p-GSK-3β(ser9)的表达量,免疫荧光观察其细胞内定位情况。结果:据MTT结果选择Li Cl 20 mmol/L处理6 h,处理后24、48、72 h,SKOV3细胞顺铂的半数抑制浓度从处理前的(20.37±0.56)、(7.79±0.72)、(2.8±0.32)μg/ml增加至(27.57±0.81)、(12.15±1.00)、(5.84±0.64)μg/ml,差异均有统计学意义。流式结果显示,Li Cl处理后SKOV3细胞内p-GSK-3β(ser9)的平均荧光强度由处理前的661.67±37.63增加到1 191.33±30.37,差异有统计学意义(P<0.05)。免疫荧光结果提示,Li Cl处理后SKOV3细胞核内p-GSK-3β(ser9)表达上调。结论:Li Cl预处理后卵巢癌细胞顺铂耐药性的增强可能与GSK-3β失活性磷酸化水平增加,尤其是与核内水平上调有关。
Fuzzy working state evaluating function and its algorithm for analogue circuits

The working state (WS) evaluation is a valuable task in the process of failure diagnosis in the analogue circuits. A fuzzy evaluating algorithm was proposed to quantify the working condition of analogue circuit regarded as fuzzy system. Several familiar WS evaluating functions based on fuzzy membership functions were also proposed to calculate the local working state indexes (WSI) of each node in an analogue circuit. The decision function combined with the WS evaluating functions is used to synthesize all the local WSI to the global WSI of the whole circuit. An example was presented to verify that the working status of the analogue circuits can be described by the new WS evaluating algorithm and the global WSI objectively and accurately.
Inter-operator radio interface based synchronization

The fourth generation (4G) wireless communication systems have been deployed or are soon to be deployed in many countries. However, with an explosion of wireless mobile devices and services, there are still some challenges that cannot be accommodated even by the 4G, such as the spectrum crisis and inter-cell interference. Telecom operators have turned to commit themselves to share available resources, including hardware and software resources. Therefore, with the mutual infrastructure, the 'integration' should be highlighted, especially in the fifth generation (5G) wireless systems that are expected to be deployed beyond 2020. The authors in the article proposed a potential cellular architecture, and discussed the inter-operator radio interface based synchronization (RIBS) for the 5G wireless communication systems. A scheme of inter-operator RIBS and typical scenarios, along with the analysis of the corresponding interference were given. Analysis of the shared parameters, signaling coordination of inter-operator RIBS and listening reference signal (RS) design for RIBS were also carried out.
滨海城市排水防涝对策研究——以厦门市营平片区为例

针对国内滨海城市近两年几场特大暴雨暴露出的排水安全问题,特别是滨海城市排水防涝易受外海潮位的影响,以厦门市滨海街区营平片区改造为研究实例,采用排水模型方法,分析了日常多年平均潮位及台风时风暴潮影响下片区主要积涝成因,提出合理的改造实施策略,同时对风暴潮影响下片区的内涝风险进行评估与区划,采用工程与非工程措施共同保障城市内涝安全,以期为滨海城市的排水防涝改造提供借鉴。
肾上腺皮质嗜酸性细胞瘤一例

绝大多数嗜酸性细胞瘤为良性肿瘤,恶性嗜酸性腺瘤极为罕见。恶性诊断标准为:(1)有丝分裂率>5/50;(2)非典型有丝分裂;(3)肿瘤侵及下腔静脉。一般认为<5 cm的嗜酸性细胞瘤为良性。>6 cm或肿瘤内有坏死、囊变及血窦浸润有潜在恶性。但尚无病灶出现转移的报道。鉴别诊断:(1)肾上腺嗜酸性细胞瘤与肾上腺腺瘤。一般肾上腺腺瘤内含脂肪成分,CT平扫时密度较低,增强后呈不均匀强化;部分腺瘤乏脂肪时难以和嗜酸性腺瘤进行鉴别。(2)嗜酸性腺瘤与嗜铬细胞瘤。嗜铬细胞瘤临床上易出现高血压,增强检查时呈明显均匀强化。
Characterization and target identification of a DNA aptamer that labels pluripotent stem cells

Aptamers are short stretches of nucleotides or amino-acid residues that are engineered to bind to various targets, from small chemicals to large proteins and live cells [1-5]. Aptamers are normally selected through a process called systematic evolution of ligands by exponential enrichment (SELEX), in which aptamers are selected from a random library of oligonucleotides or peptides against a target through repeated rounds of selection and amplification [2]. As a versatile affinity reagent, aptamers can be used to modulate the behavior of cells [6, 7], to detect chemical substances in solution [8, 9], as alternatives to antibodies [5, 10] and as therapeutic reagents for human diseases [11]. As aptamers are chemically synthesized in vitro, they offer a great advantage in selection, production, transportation and storage over traditional antibodies. Also, they can come with many types of chemical modifications, which is useful in cell biology. Although many aptamers have been selected against different tissues and cell types, including mouse embryonic stem cells (mESCs) [12], aptamers that specifically label human pluripotent stem cells (PSCs) are still lacking, likely due to the delicate nature of these cells. In this report, we present the first in-depth analysis of a DNA aptamer that specifically labels PSCs. We show that this aptamer can be used as an excellent affinity reagent and functions in hESC enrichment and depletion, and in induced PSC (iPSC) enrichment during reprogramming. We also present a novel approach based on the ratio of epitope expression levels across different cell types to quickly identify binding targets of a given molecule among thousands of proteins on the cell surface, bypassing the need of pull-down experiments and mass spectrometry.
Shock Structures in Charge Variable Dusty Plasmas with Effect of Strongly Coupled Dust Particles

A theoretical investigation has been carried out to study the effect of strong electrostatic interaction on the dust acoustic shock structures in strongly coupled dusty plasma with dust charge fluctuations. The fluid approach is employed, in which the strong electrostatic interaction is modeled by effective electrostatic temperature. A Burger-like equation, the coefficients of which are significantly modified by effects of strong coupling and dust charge fluctuation, is derived. It is shown that the combined effects of dust charge fluctuation, the ion/electron temperature, the ion/electron population, and strong coupling effect modify the basic properties of the dust acoustic waves in such a strongly coupled dusty plasma. The results of this work are compared with those observed by some laboratory experiments.
灰葡萄孢分生孢子产生相关基因的功能分析

灰葡萄孢(Botrytis cinerea)是一种典型的死体营养型植物病原真菌,能引起至少235种植物的灰霉病,常给农业生产带来巨大的经济损失。灰霉病危害一般造成减产20%–25%,严重时达到40%以上。近年来,随着温室大棚蔬菜种植面积的扩大,蔬菜灰霉病的发生日益严重,已成为我国设施栽培蔬菜生产中的重大障碍,其中黄淮、东北、西北等温室集中的地区,番茄灰霉病发生严重,田间产量损失日益严重。目前,防治灰霉病仍以化学防治为主,由于灰葡萄孢具有遗传变异大、繁殖速度快、适应性强以及具有多次再侵染等特点,使其对多种不同作用机制的杀菌剂产生了抗药性,导致杀菌剂的使用量逐年增大,并对农产品的安全性造成了严重威胁。因此,挖掘灰葡萄孢的致病相关基因,探究病菌致病的分子机制,探寻新的杀菌剂作用靶标,可为制定持久控制灰霉病的策略提供理论依据和实践基础。此外,灰葡萄孢是研究病原物与寄主植物互作的重要模式真菌之一,其基因的克隆及功能的鉴定对其他真菌的研究具有重要参考价值。本刊2013年第3期刊登了王璇、董金皋等发表的文章“灰葡萄孢分生孢子产生相关基因的克隆及功能分析”,作者从灰葡萄孢ATMT突变体库中筛选到一株不能产生分生孢子的突变株,克隆到一个与灰葡萄孢分生孢子产生相关的新基因BC1G_12707.1,首次发现该基因在灰葡萄孢分生孢子产生、菌核形成及致病力等方面的功能,为进一步研究灰葡萄孢分生孢子产生机理及灰葡萄孢侵染和致病机理奠定了基础。本刊在同期点评了该文。河北农业大学真菌毒素与植物分子病理学实验室在前期研究基础上,开展了灰葡萄孢BcKMO及其编码产物的在病菌生长、发育和致病过程中的功能研究,进行了灰葡萄孢犬尿氨酸单氧酶基因BcKMO调控病菌致病力的机制分析,灰葡萄孢菌核发育相关基因的功能分析等研究,进一步阐明该基因调控病菌生长、发育和致病力的分子机制。“一种与致病力相关的灰葡萄孢新基因及其应用”(专利号:ZL201210519803.9)获国家发明专利。
RUIN PROBABILITY IN THE CONTINUOUS-TIME COMPOUND BINOMIAL MODEL WITH INVESTMENT

This article deals with the problem of minimizing ruin probability under optimal control for the continuous-time compound binomial model with investment. The jump mechanism in our article is different from that of Liu et al [4]. Comparing with [4], the introduction of the investment, and hence, the additional Brownian motion term, makes the problem technically challenging. To overcome this technical difficulty, the theory of change of measure is used and an exponential martingale is obtained by virtue of the extended generator. The ruin probability is minimized through maximizing adjustment coefficient in the sense of Lundberg bounds. At the same time, the optimal investment strategy is obtained.
Changes in nitrogen budget and potential risk to the environment over 20 years (1990–2010) in the agroecosystems of the Haihe Basin, China

The nitrogen balance can serve as an indicator of the risk to the environment of nitrogen loss from agricultural land. To investigate the temporal and spatial changes in agricultural nitrogen application and its potential threat to the environment of the Haihe Basin in China, we used a database of county-level agricultural statistics to calculate agricultural nitrogen input, output,surplus intensity, and use efficiency. Chemical fertilizer nitrogen input increased by 51.7% from 1990 to 2000 and by 37.2% from 2000 to 2010, concomitant with increasing crop yields.Simultaneously, the nitrogen surplus intensity increased by 53.5% from 1990 to 2000 and by 16.5% from 2000 to 2010, presenting a continuously increased environmental risk. Nitrogen use efficiency decreased from 0.46 in 1990 to 0.42 in 2000 and remained constant at 0.42 in 2010,partly due to fertilizer composition and type improvement. This level indicates that more than half of nitrogen inputs are lost in agroecosystems. Our results suggest that although the improvement in fertilizer composition and types has partially offset the decrease in nitrogen use efficiency, the environmental risk has still increased gradually over the past 20 years, along with the increase in crop yields and nitrogen application. It is important to achieve a better nitrogen balance through more effective management to significantly reduce the environmental risk,decrease nitrogen surplus intensity, and increase nitrogen use efficiency without sacrificing crop yields.
定向越野对测绘专业学生实践能力培养的探讨

通过对试验数据的分析对比,找出了定向越野训练与测绘实践能力培养之间存在的共性,从专业实践教学的角度出发,分析了二者之间的互补性。挖掘基础教学在专业教学中的辅助作用,将基础教学与专业能力培养有机结合在一起,为培养优秀的测绘毕业生奠定了良好的基础。
Distribution characteristics and indicator significance of Dechloranes in multi-matrices at Ny-Alesund in the Arctic

In recent years, Dechloranes have been widely detected in the environment around the world.However, understanding and knowledge of Dechloranes in remote regions, such as the Arctic,remain lacking. Therefore, the concentrations of 5 Dechloranes in surface seawater, sediment,soil, moss, and dung collected from Ny-Alesund in the Arctic were measured with the concentrations 93 pg/L, 342, 325, 1.4, and 258 pg/g, respectively, which were much lower than those in Asian and European regions. The mean ratios of anti-Dechlorane Plus (DP) to total DP (?anti) in seawater, sediment, soil, moss, dung, and atmospheric samples were 0.36, 0.21, 0.18,0.27, 0.66, and 0.43, respectively. Results suggested that the main source of DP in seawater,sediment, soil, and moss was long-range atmospheric transport. However, the ratio identified in dung was different, for which the migration behavior of the organism is probably the main source of DP.
基于云计算的空间矢量数据并行处理

研究了提高空间矢量数据运算效率的分布式并行处理方法,基于微软Azure云平台设计了适用于矢量数据并行处理的3种架构方式:中心负载均衡架构、分布式静态负载均衡架构、分布式动态负载均衡架构,并分别搭建原型系统对小规模偏态分布数据和大规模数据进行叠置分析测试。试验结果表明,基于Azure云的分布式动态负载均衡架构版本原型系统可大幅度提高计算效率,对小规模偏态分布数据集可以达到超过10倍的加速比,对大规模数据集的分析计算更是达到了超过40倍的加速比,证明基于Azure云的分布式动态负载均衡架构方法是提高空间矢量数据分析效率的有效方法。
轻小型无人机航摄技术现状及发展趋势

轻小型无人机因其获取影像机动灵活、影像分辨率高、成本低等优势,成为传统航空摄影测量手段的有效补充,已在测绘地理信息、防灾减灾、反恐维稳、农业估产、水利电力工程建设、铁路、公路带状选线工程,以及西部1 ∶ 5万地形图空白区测图工程、远离大陆的岛礁测绘等诸多领域发挥了积极作用。本文针对当前民用轻小型无人机航摄系统开展航空摄影和影像摄影测量处理的情况,从航空摄影航线设计、搭载传感器情况、航摄质量快速检查、像控测量工作及影像摄影测量处理等方面阐述了现阶段民用轻小型无人机航空摄影及影像摄影测量处理的现状,分析了现阶段轻小型无人机航摄技术存在的问题,对下一阶段轻小型无人机航摄技术的发展提出了建议。
网状地图自动化示意化设计规则研究综述

示意地图由于其简单清晰的表达,已经被广泛应用于展示公共交通路线。然而当前示意地图制作是以计算机绘图软件辅助的半自动方式进行的,耗时耗力且极大依赖于制图者的经验和技能,因此自动化生成示意地图已经被很多研究人员所关注。在网状地图自动示意化研究中,示意地图设计规则制定是开发自动化示意化方法的基础,直接决定着示意结果图的质量。本文对现有自动化示意化方法中使用的设计规则加以了综述,首先将现有设计规则根据其应用目的的不同分为3类,即单线图形处理、网络图形处理、地图颜色和注记配置,并简要介绍了实现每条规则在当前研究中所采用的方法,之后指出了现有规则中仍需改善的几个方面并提供了可能的改进方向,其中包括网络图形示意化和设计规则制定方式,以期进一步推动网状地图自动化示意化研究的深入。
水田SAR后向散射强度及干涉相干特性研究

利用2007—2011年获取的ALOS PALSAR HH极化方式的FBS及FBD共21景数据,结合实地1 ∶ 500土地利用分类图,对苏南无锡惠山试验区进行了水稻田后向散射强度的时间特性试验及干涉相干特性分析。试验结果表明:该区水稻田后向散射强度随生长周期的变化而变化,且与各生长阶段的灌溉需水规律的变化一致,需水量越大,后向散射强度值越小。干涉相干特性试验表明:同期干涉相干系数略高于非同期干涉相干系数,且在同期干涉试验中,时间基线相同的情况下,非水稻种植期的干涉相干系数达到最高,其值明显高于水稻种植期的相干系数,该试验结果对苏南地表沉降监测SAR影像干涉对的选取及地物变化检测具有重要的参考价值。
Prospective use of bacteriocinogenic Pediococcus pentosaceus as direct-fed microbial having methane reducing potential

Direct-fed microbials (DFM), generally regarded as safe status, are successfully used in improving rumen ecology, gastro-intestinal health, feed efficiency, milk production and growth rate in ruminants. On the other hand, methanogenesis in rumen, which accounts for a significant loss of ruminant energy and increased greenhouse gas in environment, is of great concern, therefore, use of DFM for improving productivity without compromising the animal health and ecological sustainability is encouraged. The present study was conducted to investigate the methane reducing potential of bacteriocinogenic strain Pediococcus pentosaceus-34. Since, the culture showed no hemolysis on blood agar and DNase activity, hence, it was considered to be avirulent in nature, a prerequisite for any DFM. The culture also showed tolerance to pH 5.0 for 24 h with 0.5% organic acid mixture, whereas when given a shock for 2 h at different pH and organic acids concentrations, it showed growth at pH 3.0 and 4.0 with 0.1 and 1.0% organic acids, respectively, as having good animal probiotics attributes. The total gas production was significantly (P<0.05) higher in live pedicoccal culture (LPC) and dead pedicoccal culture (DPC) both with wheat straw, when compared to the control. In sugarcane bagasse, gas production was significantly lower (P<0.05) with LPC compared to the control and DPC both. Methane was reduced by the inclusion of LPC in sugarcane bagasse (0.07 mL CH_4 mg~(–1) dry matter digestibility) with no effect on other rumen fermentation parameters. However, with wheat straw and LPC total gas, in vitro dry matter digestibility, total volatile fatty acids increased significantly but no reduction in methane production was observed in comparison to the control. Therefore, further research is warranted in this direction, if the bacteriocinogenic strains can be used as DFM for ruminants to improve the ruminant productivity.
Direct-fed microbial: Animal nutrition and reproduction responses

Manipulating the gastrointestinal microbial ecosystem to enhance animal performance and reproductive responses has been one of the main goals of animal science researchers and veterinarians. Recent restrictions to the use of antimicrobials as growth promoters led researchers to seek alternative practices that can show promise both from the standpoint of efficacy as well as from the practical and economic aspects. One of the alternatives that surfaced as very promising in the last few decades is the use of direct-fed microbials (DFM) as a means to modulate the effects of the gastrointestinal microbiome on the host immune status, health and productivity.
Effects of long-term phosphorus fertilization and straw incorporation on phosphorus fractions in subtropical paddy soil

Study on soil phosphorus (P) fraction is an important aspect in probing the mechanisms of soil P accumulation in farmland and mitigating its losing risk to the environment. We used a sequential extraction method to evaluate the impacts of long-term fertilization and straw incorporation on inorganic, organic, and residual P (P_i, P_o, and Pre) fractions in the plow layer (0-20 cm) of acidic paddy soil in southern China. The experiment comprised of six treatments: (i) no fertilizer control (CK); (ii) straw incorporation and green manure (SG); (iii) nitrogen and P fertilizer (NP); (iv) NP+SG; (v) NP+K fertilizer (NPK); and (vi) NPK~+SG. The results showed that, compared to the initial total soil P content (TSP, 600 mg kg~(-1) in 1990), long-term (20 years) combined continuous P fertilizer and SG significantly increased P accumulation (by 13-20%) while single fertilization (39.3 kg P ha~(-1) yr~(-1)) could maintain soil P status at the most. The average soil P fractions comprised of extractable P_i, P_o, and P_(re) by 51.7, 33.4, and 14.9% in total soil P, respectively. With comparison of no fertilizer addition (CK), long-term single fertilization significantly (P<0.05) increased the accumulation of NaHCO_3~-, NaOH~-, and HCl~- extractable P_i fractions accounting for two-to three-fold, while SG increased the accumulation of NaHCO_3~- and NaOH~- extractable Pi and P_o accounting for 12-60%. Though the mobilization of P_(re) fractions was not significant (P>0.05), our data indicate that SG may partially substitute for fertilizer P input and minimizing soil P accumulation and subsequent environmental risk in the subtropical paddy soil.