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Litter production and leaf nutrient concentration and remobilization in response to climate seasonality in the central Amazon

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Journal of Forestry Research 2024年第3期35卷 131-141页

作者： Ricardo Antonio Marenco saul alfredo antezana-vera Daniela Pereira Dias Luiz Antonio Candido Instituto Nacional de Pesquisas da Amazonia Coordenagao de Uso da Terra e Mudanca ClimaticaAv.Andre Araujo 2936ManausAM69067-375Brazil Programa de pos-Graduagao em Agricultura no Tropico Umido Instituto Nacional de Pesquisas da Amazonia-INPAManausAMBrazil Unidade Academica de Ciencias Agrarias Universidade Federal de JataiBR 364km 195JataiGO 75801-615Brazil

Litterfall is the largest source of nutrients to for-est soils of tropical ***,variability in lit-terfall production,nutrient remobilization,and changes in leaf nutrient concentration with climate seasonality remain largely unknown for the central *** study meas-ured litterfall production,leaf nutrient remobilization,and leaf area index on a forest plateau in the central *** was measured at monthly intervals during 2014,while nitrogen,phosphorus,potassium,calcium and mag-nesium concentrations of leaf litter and canopy leaves were measured in the dry and rainy seasons,and remobilization rates *** area index was also recorded in the dry and rainy *** litterfall varied from 33.2(in the rainy season)to 87.6 g m^(-2) in the dry season,while leaf area index increased slightly in the rainy *** seasonality had no effect on concentrations of nitrogen,calcium,and magnesium,whereas phosphorous and potassium responded to rainfall seasonality *** phosphorous increased,potassium decreased during the dry *** seasons,nitrogen,potassium,and phosphorous decreased in leaf litter;calcium increased in leaf litter,while magnesium remained unaffected with leaf ***,the five nutrients had similar remobilization rates over the *** absence of climate seasonality on nutrient remobilization suggests that the current length of the dry season does not alter nutrient remobilization rates but this may change as dry periods become more prolonged in the future due to climate change.

关键词： Throughfall Nutrient cycling Climatic seasonality Leaf mass per area

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Sap flow rates of Minquartia guianensis in central Amazonia during the prolonged dry season of 2015–2016

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Journal of Forestry Research 2021年第5期32卷 2067-2076页

作者： saul A.antezana-vera Ricardo A.Marenco Botany Graduate Program Instituto Nacional de Pesquisas da Amazônia-INPAAvenida AndréAraújo2936ManausAM 69067-375Brazil Tree Ecophysiology LaboratoryInstituto Nacional de Pesquisas da Amazônia-INPAAvenida AndréAraújo2936ManausAM 69067-375Brazil

Minquartia guianensis *** a slow-growing species with several *** the juvenile state,it is well-adapted to low light conditions of the forest ***,it is still unknown how climate variability affects transpiration of this species,particularly under drought *** this study,we aimed to assess the effect of climatic variability on sap flow rates(SFR).SFR and radial growth were measured in six trees(14-50 cm diameter)in 2015 and ***(precipitation,irradiance,relative humidity and temperature)and soil water content(SWC)data were also *** tended to increase in the dry season,with a negative relationship between SFR and SWC and precipitation(p<0.001),while there was a positive association between radial growth and monthly precipitation(p=0.004).Irradiance and temperature were the environmental factors more closely correlated with SFR during daytime(p<0.001),whereas relative humidity and vapor pressure deficit were the most important factors at night(p<0.001).Although negative SFR were sometimes recorded at night,the mean nocturnal sap flow was positive and across trees the nighttime sap flow accounted for 12.5%of the total daily sap *** transpiration during the dry season suggests that the root system of Minquartia was able to extract water from deep soil *** results widen our understanding of the ecophysiology of Amazonian trees under drought and provide further insight into the potential effect of the forecasted decline in precipitation in the Amazon region.

关键词： Reverse sap flow Soil water content Transpiration Tree growth

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Refinement of the Proposed Gamma-Ray Burst Time Delay Model

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International Journal of Astronomy and Astrophysics 2024年第2期14卷 120-147页

作者： Godson Fortune Abbey Joseph Simfukwe Prospery Christopher Simpemba saul Paul Phiri Alok Srivastava Golden Gadzirayi Nyambuya Department of Physic School of Mathematics and Natural Sciences The Copperbelt University Kitwe Republic of Zambia Fundamental Theoretical and Research Group Department of Applied Physics Faculty of Applied Sciences National University of Science & Technology Bulawayo Republic of Zimbabwe

This paper is the second instalment in our study of the observed time delay in the arrival times of radio photons emanating from Gamma Ray Bursts (GRBs). The mundane assumption in contemporary physics as to the cause of these pondersome time delays is that they are a result of the photon being endowed with a non-zero mass. While we do not rule out the possibility of a non-zero mass for the photon, our working assumption is that the major cause of these time delays may very well be that these photons are travelling in a rarefied cosmic plasma in which the medium’s electrons interact with the electric component of the Photon, thus generating tiny currents that lead to dispersion, hence, a frequency-dependent speed of Light (FDSL). In the present instalment, we “improve” on the model presented in the first instalment by dropping the assumption that the resultant pairs of these radio photons leave the shock front simultaneously. The new assumption of a non-simultaneous— albeit systematic—emission of these photon pairs allows us to obtain a much more convincing and stronger correlation in the time delay. This new correlation allows us to build a unified model for the four GRBs in our sample using a relative distance correction mechanism. The new unified model allows us to obtain as our most significant result a value for the frequency equivalence of the interstellar medium (ISM)’s conductance ν* ~ 1.500 ± 0.009 Hzand also an independent distance measure to the GRBs where we obtain for our four GRB samples an average distance of: ~69.40 ± 0.10, 40.00 ± 0.00, 58.40 ± 0.40, and 86.00 ± 1.00 Mpc, for GRB 030329, 980425, 000418 and 021004 respectively.

关键词： Gamma-Ray Bursts (GRB) Photon Mass Plasma Time Delay Fireball Model

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逻辑的问题

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哲学分析 2024年第4期15卷 108-134,198,199页

作者： [美]索尔·克里普克李莉(译) 纽约城市学院湖北大学哲学学院

在逻辑认识论中,有这样一个蒯因式教条:逻辑与其他科学理论之间没有明显的分别,逻辑只是用来组织经验的工具之一。最初“采用”的经典逻辑就很好地经受住了经验的考验。普特南在其著名论文《逻辑是经验的吗?》中也提出“采用”一种特定... 详细信息

在逻辑认识论中,有这样一个蒯因式教条:逻辑与其他科学理论之间没有明显的分别,逻辑只是用来组织经验的工具之一。最初“采用”的经典逻辑就很好地经受住了经验的考验。普特南在其著名论文《逻辑是经验的吗?》中也提出“采用”一种特定的非经典逻辑来解决量子力学基础问题的建议。克里普克则从论证过程、直觉在其中所起的作用以及方法论层面对普特南的论证进行了反驳。他分析指出,考虑到UI定律在实际推理中失效的例子,这种“采用”另一种逻辑的想法是得不到辩护的。即使退一步,采用的是一种规则而不是陈述,在实际推理中也可能无法从全称陈述推出特殊实例。其次,他讨论了矛盾律的情况、合取的情况,指出不能把逻辑定律当作假设从而得出结果,而是需要逻辑推理才能得出这些结果,不可能有一个中立的立场来讨论脱离逻辑本身得出结果的问题。最后,他认为不存在不同的逻辑,其实只有一种逻辑,即只有推理。如果一个新的形式系统有一些有趣的非正式解释,那么它可能体现了合理的逻辑原则,但不能“采用”它,只能尝试证明某个形式系统体现了(a)合理的原则,(b)某些联结词领域的完全的原则。广义来看,可能会有以前没有考虑过的新联结词,这可以称为“一种新的逻辑”。然而,发现逻辑规律,甚至找到几个世纪以来一直认为是合理原则的东西实际上是基于谬误的理由,并非因为“采用”了一种新的逻辑。

关键词：采用问题量子逻辑推理规则择代系统

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Genetic characteristics and molecular diagnostics of bone tumors

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Journal of Cancer Metastasis and Treatment 2021年第1期7卷 111-132页

作者： David Suster saul Suster Department of Pathology Rutgers UniversityNew Jersey Medical SchoolNewarkNJ 07103USA Department of Pathology Medical College of WisconsinMilwaukeeWI 53226USA

The diagnosis of primary tumors of bone relies heavily on clinicopathological and radiological correlation and is often best performed in a multidisciplinary *** tumors comprise a heterogenous category of human lesions ranging from benign to malignant *** tumors affect a wide age range and can become problematic for diagnosis when less common entities are *** the pathological diagnosis of many bone tumors has been based primarily on the evaluation of hematoxylin and eosin-stained glass slides,sometimes combined with ancillary diagnostic techniques such as immunohistochemistry,conventional cytogenetics,fluorescence in situ hybridization,and polymerase chain reaction-based *** recently,the advent of massively parallel sequencing-based techniques has opened new avenues for diagnostic testing in bone tumors;however,these new testing modalities are sensitive to traditional decalcification procedures that are commonly used in the routine processing of bony *** we provide a focused review concentrating on the molecular genetic features of bone tumors with specific,recurrent genetic alterations that make them appealing targets for directed ancillary testing by conventional or molecular *** addition,specimen handling with regards to decalcification procedures are discussed and the different types of testing modalities available are reviewed.

关键词： Molecular pathology next generation sequencing bone tumors sarcoma decalcification

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Failure of P-selectin blockade alone to protect the liver from ischemia-reperfusion injury in the isolated blood-perfused rat liver

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World Journal of Gastroenterology 2008年第44期14卷 6808-6816页

作者： Samuel Wyllie Neal R Barshes saul J Karpen John A Goss Michael E. DeBakey Department of Surgery Liver Transplant Center LaboratoryBaylor College of MedicineHoustonTX 77030United States

AIM： To determine if blockade of P-selectin in the isolated blood-perfused cold ex vivo rat liver model protects the liver from ischemia-reperfusion injury. METHODS： The effect of P-selectin blockade was assessed by employing an isolated blood-perfused cold ex vivo rat liver with or without P-selectin antibody treatment before and after 6 h of cold storage in University of Wisconsin solution. RESULTS： In our isolated blood-perfused rat liver model, pre-treatment with P-selectin antibody failed to protect the liver from ischemia-reperfusion injury, as judged by the elevated aspartate aminotransferase activity. In addition, P-selectin antibody treatment did not significantly reduced hepatic polymorphonuclear leukocyte accumulation after 120 min of perfusion. Histological evaluation of liver sections obtained at 120 min of perfusion showed significant oncotic necrosis in liver sections of both ischemic control and P-selectin antibody-treated groups. However, total bile production after 120 rain of perfusion was significantly greater in P-selectin antibody-treated livers, compared to control livers. No significant difference in P-selectin and ICAM-1 mRNAs and proteins, GSH, GSSG, and nuclear NF-kB was found between control and P-selectin antibody-treated livers. CONCLUSION： In conclusion, we have shown that blockade of P-selectin alone failed to reduced polymorphonuclear leukocyte accumulation in the liver and protect hepatocytes from ischemia-reperfusion injury in the isolated blood-perfused cold-ex vivo rat liver model.

关键词： P-selectin Ischemia-reperfusion Antibody-blockade Liver Rat

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Adding sweet sorghum juice into current dry-grind ethanol process for improving ethanol yields and water efficiency

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International Journal of Agricultural and Biological Engineering 2015年第2期8卷 97-103页

作者： Nana B Appiah-Nkansah Kaelin saul William L Rooney Donghai Wang IGERT Trainee in Biorefining Kansas State UniversityManhattan KS 66506USA Department of Biological and Agricultural Engineering Kansas State UniversityManhattanKS 66506USA Department of Soil and Crop Science Texas A&M UniversityCollege StationTX 77843USA

Sweet sorghum is a promising energy crop due to its low fertilizer and water requirements,short growth period,and high biomass ***,the challenge for sweet sorghum as a feedstock for ethanol production is its short harvest period and the extreme instability of its juice,both of which make achieving a year-round production process *** way to solve this challenge and to meet the growing demand of bio-renewable ethanol is to incorporate sweet sorghum juice into the current dry-grind ethanol *** the dry-grind process,the whole grain kernel is milled and fermented to produce *** this study,sweet sorghum juice with varying grain sorghum flour contents was liquefied,saccharified,fermented,and distilled to produce *** yield from sweet sorghum juice with the optimum grain sorghum flour loading was about 28% higher than that from the conventional ethanol *** hydrolysis with this process could be reduced by 30 *** fermentation performance of sweet sorghum juice with grain flour using a raw starch hydrolyzing enzyme was also investigated,and ethanol yield was about 21% higher than that from the conventional *** innovative technology enabling ethanol production from sweet sorghum juice could improve ethanol yield,save energy,and significantly decrease water use in the current dry-grind ethanol process.

关键词： sweet sorghum biomass ethanol yield hydrolyzing time conversion efficiency

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Zika virus is arriving at the American continent

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Asian Pacific Journal of Tropical Medicine 2016年第10期9卷 997-999页

作者： saul Levy-Blitchtein Juana del Valle-Mendoza Medicine School Health Sciences FacultyUniversidad Peruana de Ciencias Aplicadas (UPC) Research Center and Innovation of the Health Sciences Faculty Universidad Peruana de Ciencias Aplicadas (UPC) Instituto de Investigación Nutricional (IIN)

Zika virus is the last arbovirosis arriving at the American continent and it is able to produce severe complications due to its neurotropism, such as microcephaly and it is also associated with Guillain-Barre syndrome(GBS). Presence of Aedes aegypti in many regions of Peru makes it easier to spread and it could be present in population, not being detected because there is a lack of rapid diagnosis methods. It is important to make a quick, effective and combined response to this new threat.

关键词： Zika virus Arbovirosis Dengue virus Chikungunya Aedes aegypti

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An Invasive Succulent Plant (Kalanchoe daigremontiana) Influences Soil Carbon and Nitrogen Mineralization in a Neotropical Semiarid Zone

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Pedosphere 2018年第4期28卷 632-643页

作者： Ileana HERRERA Jose R. FERRER-PARIS Diana BENZO saul FLORES Belkis GARCIA Jafet M. NASSAR Ecuela de Ciencias Ambientales Universidad Espiritu Santo Guayaquil 091650 (Ecuador) Centro de Ecologla Instituto Venezolano de Investigaciones Cientificas (IVIC) Caracas 1020 (Venezuela) Centro de Estudios Botdnieos y Agroforestales Instituto Venezolano de Investigaeiones Cientificas Maracaibo 4005 (Venezuela)

It has long been recognized that plant invasions may alter carbon （C） and nitrogen （N） cycles, but the direction and magnitude of such alterations have been rarely quantified. In this study, we quantified the effects caused by the invasion of a noxious exotic plant, Kalanchoe daigrernontiana （Crassulaceae）, on C and N mineralization and enzymatic and microbial activities in the soil of a semiarid locality in Venezuela. We compared soil parameters associated with these processes （C and N mineralization time and the cumulative values, fluorescein diacetate hydrolytic activity, and activities of dehydrogenase, β-glucosidase, glucosaminidase, and urease） between invaded and adjacent non-invaded sites. In addition, correlations among these parameters and the soil physical-chemical properties were also examined to determine if a positive feedback exists between nutrient availability and K. daigremontiana invasion. Overall, our results showed that C mineralization and transformation of organic compounds to NH4^＋ were favored at sites colonized by K. daigrernontiana. With this species, we found the highest cumulative amounts of NH4^＋-N and C and the lowest mineralization time. These results could be explained by higher activities of urease and glueosaminidase in soils under the influence of K. daigremontiana. In addition, higher amounts of organic matter and moisture content in invaded soils might favor C and N mineralization. In conclusion, invasion of Neotropical semiarid zones by K. daigrernontiana may influence the chemical and biological properties of the soils covered by this species, increasing nutrient bioavailability, which, in time, can facilitate the invasion process.

关键词： Akaike Information Criterion C and N pools enzymatic activity NH4^+-N NO3^--N nutrient availability plant invasion

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Screening for self-renewal factors by a combination of mRNA and CGH microarray in human embryonic stem cells

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Frontiers in Biology 2010年第5期5卷 431-438页

作者： Lei XIAO Lixiazi HE saul J.SHARKIS Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins Johns Hopkins University School of MedicineBaltimoreMD 21231USA Laboratory of Molecular Cell Biology Institute of Biochemistry and Cell BiologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200031China

Human embryonic stem cells(hESCs)undergo self-renewal while maintaining ***,the molecular mechanism that demonstrates how these cells maintain their undifferentiated state and how they self-renew is poorly ***,we characterized an aneuploidy H1 hESC subline(named H1T)using karyotyping and comparative genomic hybridization(CGH)*** the H1T hESC line displays a self-renewal advantage while maintaining an undiffer-entiated state,we speculated that the expression patterns of speciﬁc genes which are related to pluripotency or differentiation were altered;therefore,we attempted to screen for molecules that are propitious for maintenance of stemness by performing a combination of mRNA and CGH microarray analysis which compared the aneuploidy H1T hESC subline versus the euploid H1 hESC *** is discovered that some genes are up-regulated in H1T hESC subline such as TBX2 and Wnt3,while some are downregulated,for example,Fbxo7 and ***ﬁndings should fascilitate the study of the complex signaling network which maintains hESC pluripotency and function.

关键词： self-renewal mRNA microarray comparative genomic hybridization(CGH)microarray

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