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Ecological Processes 2018年第1期7卷 333-347页

作者： Wuletaw Mekuria Kindu Mekonnen Peter thorne.Melkamu Bezabih Lulseged Tamene Wuletawu Abera Centre for Rural Development College of Development StudiesAddis Ababa UniversityP.O.Box 1176Addis AbabaEthiopia International Livestock Research Institute(ILRI) P.O.Box 5689Addis AbabaEthiopia International Center for Tropical Agriculture(CIAT) P.O.Box 5689 Addis AbabaEthiopia

Introduction:Ethiopia has made efforts to tackle the challenges of low crop and livestock productivity and degradation of land resources through various rural development ***,increasing demands for food,animal feed,fuel,and income-generating activities are putting pressure on the *** this paper,we describe the production pressure and competition between crop and livestock production,quantify rates of land-use/cover(LULC)changes,and examine driving forces and consequences of land ***:The study was conducted in Gudo Beret watershed,North Shewa Zone of Amhara region,*** used a combination of methods including remote sensing,household interviews,field observations,focus group discussions,and key informant *** and unsupervised image classification methods were employed to map LULC classes for 31 years(1984–2016).Results:The results of satellite remote sensing revealed that 51%of the land in the study area was subject to accelerated land *** household survey results indicated that feed resources and grain production pressures were 1.43 and 1.34 t ha^(−1) *** observed annual changes in plantation and settlement areas were 2.6%and 2.9%.This was mainly at the expense of bushland and grazing land *** increased(0.4%year^(−1))while grazing land reduced(3.5%year^(−1))under contrasting dynamics and competitive *** increase in human and livestock populations and farm expansion were major drivers of land conversion that adversely affected household livelihoods and the natural *** consequences of these pressures resulted in a lack of animal feed,low crop-livestock productivity,and a reduction in natural vegetation ***:We suggest that sustainable land resource management,more integrated crop-livestock production,and the use of productivity-enhancing technologies could play a role in managing competition for land resources.

关键词： Cropland Land pressure Livestock Population growth Production dynamics

A new metric for ranking high-performance computing systems

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National Science Review 2016年第1期3卷 30-35页

作者： jack Dongarra Michael A.Heroux Piotr Luszczek Innovative Computing Laboratory EECS DepartmentUniversity of Tennessee

INTRODUCTION Performance benchmarks play an important role in various stages of hardware development and *** development,hardware designers use benchmarks as proxies for full-fledged applications because prototype sys... 详细信息

关键词： code A new metric for ranking high-performance computing systems PDEs NPB high

Fusarium pseudograminearum and *** affect the root system architecture of bread wheat

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作物学报：英文版 2023年第1期11卷 316-321页

作者： Ahmed Saad jack Christopher Anke Martin Stephen McDonald Cassandra Percy Centre for Crop Health University of Southern QueenslandToowoombaQLD 4350Australia University of Queensland Queensland Alliance for Agriculture and Food Innovation(QAAFI)Leslie Research FacilityToowoombaQLD 4350Australia

Yield losses of bread wheat due to crown rot can be more severe when drought conditions occur during the grain-filling *** architecture characteristics are important for soil exploration and belowground resource acquisition and are essential for adaptation to water-limited *** such as root angle,length and density have been strongly associated with acquisition efficiency and contribute to yield stability of the *** impact of crown rot pathogens on wheat root architecture is poorly *** examined differences in root angle,length and number,as well as dry root weight of the crown rot-susceptible bread wheat cultivar,Livingston inoculated with one of two crown rot pathogens Fusarium culmorum or Fusarium pseudograminearum in a transparent-sided root observation *** adverse impacts on plant health and growth were revealed by visual discolouration of the leaf sheaths;fresh and dry shoot weight;leaf area of the oldest and the youngest fully expanded leaf and leaf *** of most recorded root system measurements were reduced when inoculated with either *** or *** contrast,root angle was increased in the presence of *** but was not significantly changed by *** development of whiteheads and grain losses in bread wheat caused by crown rot have previously been associated with blockages of the vascular *** method employed here was able to identify differences in the pathogen impacts on roots,which were not detected using previous *** research indicates that in the presence of *** and *** infection,not only reductions in the size and biomass of the shoot system but also changes in the length,biomass and architecture of the root system could play an important role in yield loss.

关键词： Crown rot Root characteristics Livingston Wheat

Disturbance cue communication is shaped by emitter diet and receiver background risk in Trinidadian guppies

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Current Zoology 2022年第4期68卷 433-440页

作者： jack A Goldman Adam L Crane Laurence E A Feyten Emily Collins Grant E Brown Department of Biology Concordia University7141 Sherbrooke Street WestMontrealQCCanada H4B 1R6

In animal communication systems,individuals that detect a cue(i.e.,“receivers”)are often influenced by characteristics of the cue *** instance,in many species,receivers avoid chemical cues that are released by emitters experiencing *** chemical“disturbance cues”appear to benefit receivers by warning them about nearby danger,such as a predator’s *** the active ingredients in disturbance cues have been largely unexplored,by-products of metabolized protein are thought to play a role for some *** so,the content(quality)and volume(quantity)of the emitter’s diet should affect their disturbance cues,thus altering how receivers perceive the cues and *** Poecilia reticulata are a species known to discriminate among disturbance cues from different types of donors,but dietary variation has yet to be *** this study,we found evidence that diet quality and quantity can affect disturbance cues released by guppy emitters(i.e.,experimental“donors”).Receivers discriminated between donor cue treatments,responding more strongly to cues from donors fed a protein-rich bloodworm diet(Experiment 1),as well as an overall larger diet(Experiment 2).We also found that receivers exposed to higher background risk were more sensitive to disturbance cue variation,with the strongest avoidance responses displayed by high-risk receivers toward disturbance cues from donors fed the high-quality ***,diet,and perhaps protein specifically,affects either the concentration or composition of disturbance cues released by *** variation may be important in information signaling in social species like the guppy.

关键词： alarm cues chemical cues diet quality diet quantity protein

Effect of inflammatory bowel disease treatments on patients with diabetes mellitus

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World Journal of Diabetes 2021年第8期12卷 1248-1254页

作者： Joshua Ashley jack Bower Lauren O'Flynn Rakhi Kakad David Aldulaimi Department of Gastroenterology South Warwickshire Foundation TrustWarwick CV345BWUnited Kingdom Department of Endocrinology South Warwickshire Foundation TrustWarwick CV345BWUnited Kingdom

As medical care progresses and the number of patients with chronic conditions increases there is the inevitable challenge of managing patients with multiple *** bowel disease(IBD)is an umbrella term for are inflammatory conditions affecting the gastrointestinal tract,the two most common forms being Ulcerative Colitis and Crohn’s *** diseases,usually diagnosed in young adults,exhibit a relapsing and remitting course and usually require longterm *** can be treated with a number of topical and systemic *** conducted a review of the current published evidence for the effects these medications can have on diabetes mellitus(DM)and glycaemic *** were conducted on medline and embase with a timeframe from 1947(the date from which studies on embase are recorded)to November *** publications were selected and *** evidence of the impact of aminosalicylates,corticosteroids,thiopurines,and biologic agents was *** there was limited evidence for certain agents,IBD medications have been shown to have an effect of DM and these effects should be considered in managing patients with dual *** effects of steroids on blood sugar control is well documented,but consideration of other agents is also *** patients requiring steroids for Ulcerative Colitis,locally acting steroid agents delivered rectally may be preferred to minimise side effects in those with distal bowel Ulcerative Colitis.A switch to other agents should be considered as soon as possible in people with diabetes to limit the impact on glycaemic control.5-aminosalicylates appear to play a role in the reduction of hemoglobin A1c(HbA1c),although the literature suggests these may be falsely low ***,monitoring of people with diabetes on these agents may require daily monitoring of capillary blood sugars rather than relying simply on HbA1c;for example fructosamine performed 3-6 monthly,although th

关键词： Inflammatory bowel disease Diabetes mellitus Crohn's disease Ulcerative colitis Anti-tumor necrosis factor-α Corticosteroids

Pine wilt disease: a short review of worldwide research

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Forestry Studies in China 2011年第2期13卷 132-138页

作者： Alexander Yu. RYSS Oleg A. KULINICH jack R. SUTHERLAND Zoological Institute of Russian Academy of Sciences Universitetskaya Embankment Centre of Parasitology A.N. Severtsov Institute of Ecology and Evolution Victoria British Columbia V8R 5V9

This article summarizes the results of the research papers presented at the International Symposium on pine wilt disease （IUFRO Working Party Meeting 4.04.03） held in July 2009, at Nanjing, China. The general topics covered were on pine wilt disease （PWD）, its causal organism, the pinewood nematode （PWN） Bursaphelenchus xylophilus, plus other PWN-associated microorganisms that play a significant role in PWD such as bacteria （e.g. Pseudomonasfluorescens）. Most of the papers that are reviewed are based on work on PWD-PWN in East Asia and Russia. Specific topics covered include： 1） the fundamental conceptions of PWD development, 2） pathogenicity, 3） host-parasite relationships including the histopathology of diseased conifers and the role of toxins from bacteria-nematode ecto-symbionts, 4） PWN life cycle and transmission, 5） B. xylophilus dissemination models, 6） associations （with other nematodes）, 7） diagnostics, 8） quarantine and control of the PWN and 9） biocontrol of the PWN.

关键词： pine wilt disease pinewood nematodes forestry control Bursaphelenchus Pseudomonas Esteya review

Insight into the growth behaviors of MoS_(2)nanograins influenced by step edges and atomic structure of the substrate

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Nano Research 2022年第8期15卷 7646-7654页

作者： Shuangyue Wang Ni Yang Mengyao Li Ji Zhang Ashraful Azam Yin Yao Xiaotao Zu Liang Qiao Peter Reece John Stride jack Yang Sean Li School of Materials Science and Engineering UNSW SydneyNSW 2052Australia School of Physics University of Electronic Science and Technology of ChinaChengdu 610054China School of Physics UNSW SydneyNSW 2052Australia School of Chemistry UNSW SydneyNSW 2052Australia

The step edges and intrinsic atomic structure of single-crystal substrate play a critical role in determining the growth pathways of transition metal dichalcogenide(TMD)grains,particularly whether the TMDs will grow into wafer-scale single-crystal or anisotropic ***,we investigate the growth behaviours of the MoS_(2)nanograins on(0001)and()sapphire *** one hand,the step edges formed on the(0001)surface after thermal treatment are found to promote the macroscopic aggregation of MoS_(2)nanograins and to form unidirectional large triangular islands along with thesteps in the annealing process,while on the pristine(0001)surface,the MoS_(2)nanograins grow into a random network-like ***,oxygen treatment on the substrate can further enhance the growth of MoS_(2)*** electron microscopy and fast Fourier transform patterns reveal that the substrate could modulate the orientation of MoS_(2)nanograins during their growing *** the other hand,the MoS_(2)nanograins on the surface could self-assemble into one-dimensional nanoribbons due to the strong structural anisotropy of the *** addition,the ratio of Raman intensities for peaks that correspond to the and A1g phonon modes shows a linear relationship with the grain size due to the change of the“phonon confinement”.Moreover,new peaks located at 226 and 280 cm−1 can be observed in the off-resonant and resonant Raman spectra for the MoS_(2)nanograin samples,respectively,which can be attributed to the scatterings from the edges of as-fabricated MoS_(2)nanostructures.

关键词： MoS_(2)nanograins growth behaviors step edges atomic structure Raman spectra evolution UV-vis absorption

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桑尼的启示

海外英语 2003年第12期 34-35页

作者： jack 安徽省淮南市安徽理工大学外语系

　　Sunny's grandfather had suddenly taken ill and was not able to play with him any more like he used to before. Little Sunny was very sad and felt very lonely. He would go and sit by his grandfather's bed, waiting for him to get up and play with him again. At night, he would think of the little cowherd1 boy, Krishna, and pray to him fervently2 to make his grandfather well again. But, little Krishna was busy having fun, and would not answer Sunny's prayers. Sunny knew Krishna was always happy and busy having fun, so he did not mind.……

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GUARDIN is a p53-responsive long noncoding RNA that is essential for genomic stability

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GUARDIN is a p53-responsive long noncoding RNA that is essen...