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How Specific is Non-Hypersensitive Host and Nonhost Resistance of Barley to Rust and Mildew Fungi?

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Journal of Integrative Agriculture 2014年第2期13卷 244-254页

作者： Niks R e Laboratory of Plant Breeding Wageningen UniversityP.O.Box 3866700 AJ WageningenThe Netherlands

Full nonhost resistance can be defined as immunity, displayed by an entire plant species against all genotypes of a plant pathogen. Interesting biological questions are, whether the genes responsible for the nonhost status of a plant species have a general or a specific effectiveness to heterologous （＂nonhost＂） pathogens？ Is the nonhost resistance to pathogens of plant species that are related to the nonhost based on R-genes or on other types of genes？ We study this question in barley （Hordeum vulgare L.）, which is a near-nonhost to several rusts （Puccinia） of cereals and grasses. By crosses and selection we accumulated susceptibility and developed an experimental line, SusPtrit, with high susceptibility to at least nine different heterologous rust taxa such as the wheat and Agropyron leaf rusts （P. triticina and P. persistens, respectively）. At the microscopic level there is also some variation among barley accessions in the degree that the heterologous wheat powdery mildew （Blumeria graminis ***. tritici） is able to form haustoria in epidermal cells. So, also the genetics of the variation in level of nonhost resistance to heterologous mildew fungi can be studied in barley. Our data obtained on mapping populations involving three regular nonhost-immune accessions （Vada, Cebada Capa and Golden Promise） suggest that nonhost resistance is the joined effect of multiple, quantitative genes （QTLs） and very occasionally a major gene （R-gene？） is involved. Most QTLs have effect to only one or two heterologous rusts, but some have a wider spectrum. This was confirmed in a set of QTL-NILs. Those QTL-NILs are used to fine-map the effective genes. In some cases, a QTL region with effectiveness to several heterologous rusts might be a cluster of genes with a more narrow spectrum of effectiveness. Our evidence suggests that nonhost resistance in barley to rust and powdery mildew fungi of related Gramineae is not due to R-genes, but to pathogen species-specific quantitative resi

关键词： genetics specificity basal resistance

Sediment discharge of the Yellow River, China: past, present and future——A synthesis

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Acta Oceanologica Sinica 2015年第2期34卷 1-8页

作者： ReN Mei'e Key Laboratory of Coast and Island Development of Ministry of education School of Geographic and Oceanographic Sciences Nanjing University

The Yellow River cut through Sanmenxia Gorge and discharged into the sea via the North China Plain in 150 ka BP; since then, around 86 000 × 108 t sediment has been transported passing Sanmenxia Gorge. Based on land use and land cover changes in Loess Plateau and other available evidence, an estimate of the Yellow River sediment budget is presented here： about 72% of the sedimentary material was trapped in the North China Plain and the remainder（i.e., 26%） escaped to the sea. At the present stage, 〈 0.2×108 t/a suspended sediment of the Yellow River enter the northern Yellow Sea. The transport pattern is determined mainly by the shelf current system. Annually 0.2×108–0.3×108 t of suspended particles are carried to the east China Sea; the materials are derived mainly from coastal and subaqueous delta erosion associated with the abandoned Yellow River on the Jiangsu coast. Since 1972, the lower Yellow River started to have a situation of continuous no-flow. During 1996–2000, the annual water flow and sediment discharge are only 19%, as compared with normal years（i.e., average for 1950–1979）. In response to global warming and increase of water diversion from the Yellow River for industrial and urban use, the sediment flux of the Yellow River to the sea will most likely remain small in the next two to three decades.

关键词： Yellow River Loess Plateau sediment budget transport patterns sediment retention

Metamorphic zircon from Xindian eclogite,Dabie Terrain: U-Pb age and oxygen isotope composition

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Science China earth Sciences 2006年第1期49卷 68-76页

作者： e. Deloule CRPG-CNRS Nancy 54501France

Detailed CL image, U-Pb age and oxygen isotope composition in situ analyses for two metamorphic zircons from ultra-high pressure Xindian eclogite, Southern Dabie Terrain were carried out. There are two kinds of zircon in eclogite. The major subpopulation is podgy and isometric, and interpreted as protolith magmatic zircon with partial recrystallization. Its formation age is 811 ±22 Ma. The less abundant one is euhedral prismatic with core-rim structure and the rim being metamorphic overgrowth and formed at 221±17 Ma. Zircon CL image strength is mainly controlled by U and Th contents. The magmatic zircon has its Th/U ratio around 1.3 and decreasing with recrystallization, whereas metamorphic zircon has Th/U ratio of lower than 0.1. Magmatic and metamorphic zircon domains all show very low oxygen isotopic compositions with average δ18O values of 1.8?and 2.8? respectively. The low δ18O values in protolith zircon indicated meteoric water involvement in their magma source region. It may correlate with snowball earth event during Neoproterozoic. It also indicates that protolith zircon could survive its oxygen isotope signature during Dabie eclogite facies UHP metamorphism.

关键词： metamorphic zircon, zircon U-Pb age, zircon oxygen isotopes, eclogite, Dabie Shan.

FATIGUe CRACK PROPAGATION OF Ni-BASe SUPeRALLOYS

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Acta Metallurgica Sinica(english Letters) 2005年第1期18卷 55-64页

作者： e.Barbero Dept. of Mechanical & Aerospace engineering West Virginia University Morgantown WV 26506-6106 USA

Time-dependent Fatigue Crack Propagation (FCP) behaviors of five Ni-base superalloys were investigated at various temperatures under fatigue with various holding times and sustained loading conditions. The new concept of damage zone is defined and employed to evaluate the alloys' resistance to hold-time FCP. A special testing procedure is designed to get the maximum damage zone of the alloys. Udimet 720 and Waspaloy show shorter damage zones than alloys 706 and 718. The fractographical analyses show that the fracture surfaces of the specimens under hold-time fatigue conditions are mixtures with intergranular and transgranular modes. As the extension of holding time per cycle, the portion of intergranular fracture increases, The effects of loading stress intensity, temperature, holding time, alloy chemistry, and alloy mi-crostructure on damage zone and the crack growth behaviors are studied. Hold-time usually increases the alloy's FCP rate, but there are few exemptions. For instance, the steady state hold-time FCP rate of Waspaloy at 760℃ is lower than that without hold-time. The beneficial effect of hold-time was attributed to the creep caused stress relaxation during the hold-time.

关键词： Ni-base superalloys fatigue crack growth hold-time

Hepatocellular carcinoma: Therapy and prevention

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World Journal of Gastroenterology 2005年第47期11卷 7391-7400页

作者： Hubert e Blum Department of Medicine Ⅱ University of FreiburgD-79106 FreiburgGermany

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide. The major etiologies and risk factors for the development of HCC are well defined and some of the multiple steps involved in hepatocarcinogenesis have been elucidated in recent years. Despite these scientific advances and the implementation of measures for the early detection of HCC in patients at risk, patient survival has not improved during the last three decades. This is due to the advanced stage of the disease at the time of clinical presentation and limited therapeutic options. The therapeutic options fall into five main categories: surgical interventions including tumor resection and liver transplantation, percutaneous interventions including ethanol injection and radiofrequency thermal ablation, transarterial interventions including embolization and chemoembolization, radiation therapy and drugs as well as gene and immune therapies. These therapeutic strategies have been evaluated in part in randomized controlled clinical trials that are the basis for therapeutic recommendations. Though surgery, percutaneous and transarterial interventions are effective in patients with limited disease (1-3 lesions, ＜5 cm in diameter) and compensated underlying liver disease (cirrhosis Child A), at the time of diagnosis more than 80% patients present with multicentric HCC and advanced liver disease or comorbidities that restrict the therapeutic measures to best supportive care. In order to reduce the morbidity and mortality of HCC, early diagnosis and the development of novel systemic therapies for advanced disease, including drugs, gene and immune therapies as well as primary HCC prevention are of paramount importance. Furthermore, secondary HCC prevention after successful therapeutic interventions needs to be improved in order to make an impact on the survival of patients with HCC. New technologies, including gene expression profiling and proteomic analyses, should allow to further elucida

关键词： HCC resection Liver transplantation Percutaneous ethanol injection Radiofrequency thermal ablation Transarterial embolization or chemoembolization Chemotherapy Gene therapy Immune therapy Prevention

Search for a natural scientific measure of economy

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Frontiers of environmental Science & engineering 2011年第1期5卷 111-118页

作者： John e COULTeR Xiwangzhuang Shuangqing RdHaidianBeijing 100084China

Through human history,wealth has been measured in grain,gold,and,now,*** counterfeiting of coins and notes goes back a long way,it is only with electronic financial accounting in a global economy tainted by toxic loans and imaginary funds that there is an urgency to search for a realistic objective way to monitor and regulate what we are doing to our earth and *** schemes using analysis of utility functions,oil equivalents,entropy,energy,and other units have been tried and,while helping to understand some basic processes and flows,have always been swamped by the machinations of financiers and the attention big sums of money ***,the concept of exergy,pioneered in eastern europe in the 1950s,is being researched,developed,and applied,especially in China,driven by the desperation to measure the reality beyond the twin specters of global financial and environmental crises.A rough inventory of the matter in the biosphere at the coordinate details of an angstrom and an appreciation of how humans harness and manipulate electromagnetic forces can be enlightening as to what is and is not *** that understanding,any financial estimate and proposed stimulus packages or IMF reform will be wildly wrong and may even be headed in the wrong direction.

关键词： climate change financial crisis energy exergy environment

A New Fractional Model for the Falling Body Problem

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Chinese Physics Letters 2017年第2期34卷 1-3页

作者： A.ebaid B.Masaedeh e.e1-Zahar Department of Mathematics Faculty of ScienceTabuk UniversityP.O.Box 741Tabuk 71491Kingdom of Saudi Arabia Department of Mathematics Faculty of Sciences and HumanitiesPrince Sattam Bin Abdulaziz UniversityA1kharj11942Kingdom of Saudi Arabia Department of Basic engineering Science Faculty of EngineeringShebin El-Kom32511Menofia UniversityEgypt

Recently, a conformable fractional derivative has been proposed to calculate the derivative of non-integer order of time functions. It has been shown that this new fractional derivative definition obeys many advantages over the preceding definitions. For mathematical models in applied sciences and to preserve the dimensionality of the physical quantities, an auxiliary parameter （~r） which has the dimension of seconds should be implemented in the fractional derivative definition. We obtain analytic solutions for the resulting conformable fractional differential equations describing the vertical velocity and the height of the falling body. It is shown that the dimensions of velocity and height are always correct without any restrictions on the auxiliary parameter cr which contradicts with the results in the literature when applying the Caputo definition to the same problem. This may open the door for many future works either to describe the role of such an auxiliary parameter or to derive a more suitable definition for the fractional derivative.

关键词： A New Fractional Model for the Falling Body Problem

Social determinants of gastrointestinal malformation mortality in Brazil:a national study

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World Journal of Pediatric Surgery 2024年第2期7卷 134-141页

作者： Ayla Gerk Amanda Rosendo Luiza Telles Aricia Gomes Miranda Madeleine Carroll bruna Oliveira Trindade Sarah Bueno Motter esther Freire Gabriella Hyman Julia Ferreira Fabio Botelho Roseanne Ferreira David P Mooney Joaquim Bustorff-Silva Program in Global Surgery and Social Change Harvard Medical SchoolBostonMassachusettsUSA Faculty of Medicine and Health Sciences McGill UniversityMontrealQuebecCanada Harvey e.Beardmore Division of Pediatric Surgery The Montreal Children's HospitalMcGill University Health CentreMontrealQuebecCanada Department of Surgery Universidade Estadual de Campinas(UNICAMP)CampinasBrazil Instituto de educação Médica(IDOMeD/estácio Campus Vista Carioca)Rio de JaneiroBrazil Faculty of Medicine Universidade Federal do Delta do ParnaibaParnaibaPiauiBrazil Universidade Federal de Ciencias da Saude de Porto Alegre Porto AlegreBrazil Universidade Federal da Bahia SalvadorBrazil Department of Health Research Methods McMaster UniversityHamiltonSouthern OntarioCanada Department of Pediatric Surgery Boston Children's HospitalBostonMassachusettsUSA

Introduction In Brazil,approximately 5%are born with a congenital disorder,potentially fatal without *** study aims to evaluate the relationship between gastrointestinal congenital malformation(GICM)mortality,health indicators,and socioeconomic factors in *** GICM admissions(Q39-Q45)between 2012 and 2019 were collected using national *** demographics,socioeconomic factors,clinical management,outcomes,and the healthcare workforce density were also accounted *** Surgical Workforce density and the number of neonatal intensive care units in a region were extracted from national datasets and combined to create a clinical index termed'NeoSurg'.Socioeconomic variables were combined to create a socioeconomic index termed Socecon'.Simple linear regression was used to investigate if the temporal changes of both indexes were *** correlation between mortality and the different indicators in Brazil was evaluated using Pearson's correlation *** Over 8 years,Brazil recorded 12804 GICM *** Southeast led with 6147 cases,followed by the Northeast(2660),South(1727),North(1427),and Midwest(843).The North and Northeast reported the highest mortality,lowest NeoSurg,and Socecon Index ***,mortality rates declined across regions from 7.7%(2012)to 3.9%(2019),a 51.7%*** North and Midwest experienced the most substantial reductions,at 63%and 75%,*** significantly correlated with the indexes in nearly all regions(pe correlation between social determinants of health and GICM mortality in Brazil,using two novel indexes in the pediatric *** findings provide an opportunity to rethink and discuss new indicators that could enhance our understanding of our country and could lead to the development of necessary solutions to tackle existing challenges in Brazil and globally.

关键词： Northeast Brazil globally

Advances and challenges in diagnosing and managing adult autoimmune enteropathy

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World Journal of Gastroenterology 2025年第2期31卷 128-131页

作者： Grigorios Christodoulidis Sara e Agko Marina N Kouliou Konstantinos e Koumarelas Dimitris Zacharoulis Department of General Surgery University Hospital of LarissaLarissa 41110Greece Department of Intensive Care Unit Asklepios Paulinen Clinic WiesbadenWiesbaden 65197Germany Department of emergency Medicine General Hospital of LarissaLarissa 41221Greece Department of Surgery University Hospital of LarissaLarissa 41334Greece

Autoimmune enteropathy(AIe)is a rare immune mediated disorder primarily affecting children,characterized by chronic diarrhea,malabsorption,vomiting,weight loss and villous *** has also been observed in adults presenting diagnostic and treatment challenges due to its overlap with other gastrointestinal disorders such as celiac *** diagnostic criteria for AIe include small bowel villous atrophy,lack of response to dietary restrictions,presence of anti-enterocyte antibodies,and predisposition to autoimmunity without severe *** criteria emphasize characteristic histological findings and exclusion of other causes of villous *** is associated with various autoimmune disorders and can present with overlapping features with Celiac disease,including villous atrophy but without significant intraepithelial *** primarily involves immunosuppression using corticosteroids,calcineurin inhibitors,and anti-tumor necrosis factor therapy,alongside nutri-tional *** the challenges,understanding AIe’s diverse manifest-ations and improving diagnostic criteria are essential for effective management and improved patient *** research is needed to elucidate the pathogenesis,disease progression and long-term outcomes of AIe.

关键词： Autoimmune enteropathy Diagnosis Prognosis Adult autoimmune enter-opathy and challenges Autoimmune enteropathy and treatment Autoimmune enteropathy and diagnostic criteria Pathophysiology of autoimmune enteropathy