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Reduced normogastric electrical activity associated with emesis:A telemetric study in ferrets

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World Journal of Gastroenterology 2009年第48期15卷 6034-6043页

作者： Nathalie Percie du Sert Kit m Chu man K Wai john A Rudd paul LR Andrews Division of Basic medical Sciences St.George's University of LondonCranmer Terrace Emesis Research Group School of Biomedical SciencesFaculty of MedicineThe Chinese University of Hong KongShatinNew Territories

AIm： To characterize the gastric myoelectric activity （GmA） and intra-abdominal pressure changes induced by emetic stimuli （apomorphine and cisplatin） in the ferret. mETHODS： GmA and intra-abdominal pressure were recorded in conscious, unrestrained ferrets surgically implanted with radiotelemetry transmitters. Animals were challenged with apomorphine （0.25 mg/kg sc） and cisplatin （10 mg/kg ip）, and the emetic response was quantified via direct observation and intra-abdominal pressure recording for 1 and 4 h, respectively. The GmA was analyzed by spectral analysis; the parameters used to characterize the GmA were the dominant frequency （DF） and the repartition of spectral power in the bradygastric, normogastric and tachygastric frequency ranges. RESULTS： Retches were identified on the intraabdominal pressure trace as peaks 0.30 ± 1.01 s in duration and 59.57 ± 2.74 mmHg in amplitude, vomit peaks were longer （0.82 ± 0.06 s, P 〈 0.01） and reached a higher pressure （87.73 ± 8.12 mmHg, P 〈 0.001）. The number of retches and vomits quantified via direct observation [apomorphine： 65.5 ± 11.8 retches ± vomits （R＋V）, cisplatin： 202.6 ± 64.1 R＋V] and intra-abdominal pressure （apomorphine： 68.3± 13.7 R＋V, n = 8; cisplatin： 219.0 ± 69.2 R＋V, n = 8） were correlated （r = 0.97, P 〈 0.0001） and the timing of emesis was consistent between the 2 methods. Apomorphine induced a decrease in normogastria from 45.48% ± 4.35% to 36.70 ± 4.34% （n = 8, P 〈 0.05） but the DF of the slow waves was not changed [8.95 ± 0.25 counts/rain （cpm） vs 8.68 ± 0.35 cpm, n = 8, P 〉 0.05]. Cisplatin induced a decrease in normogastria from 55.83% ± 4.30% to 29.22% ± 5.16% and an increase in bradygastria from 14.28% ± 2.32% to 31.19% ± 8.33% （n = 8, P 〈 0.001） but the DF （9.14 ± 0.13 cpm） remained unchanged （P 〉 0.05）. The GmA changes induced by cisplatin preceded the emetic response as normogastria was reduced for 1 h before the onset of emesis （57.61% ± 5.66% to 39.91% ± 5.74%, n = 6, P 〈 0.05）. Peri-emesis

关键词： Emesis Nausea Stomach Ferret Cisplatin Apomorphine Electromyography

Analysis on variety and characteristics of maghemite

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Science China Earth Sciences 2010年第8期53卷 1153-1162页

作者： SHAW john BLOEmENDAL Jan HESSE paul ROLPH Tim Department of Earth Sciences University of Liverpool Department of Geography University of Liverpool Department of Environment and Geography Macquarie University Department of Geology University of Newcastle

maghemite (γ-Fe2O3) is a very common mineral at the earth’s surface and also an important material for making music and video tapes. maghemite is usually synthesized from magnetite under oxidizing conditions after a few hours or a few days below a temperature of 300°C. The magnetic property of thermal instability and the chemical action after heating is an important character for maghemite. That is, it will become hematite in certain proportion after being heated above 250°C. maghemite is therefore actually unable to have its Curie temperature measured. But late using synthetic sample, maghemite was further found partially thermal stable with a measurable Curie temperature ~645°C. During our thermally magnetic experiments for a set of synthetic magnetite, we found that extra fined grain size (pseudo single domain (PSD) and small multi-domain (mD), mainly 1-10 μm) magnetite was formed to a completely thermally stable maghemite. This maghemite can also be produced by heating the same powder up to 700°C in an oven and keeping this temperature for 10 min, then cooling it down. When the generated maghemite by these two ways is heated from room temperature to 700°C, it shows almost fully reversible, or thermally stable. We used X-ray powder diffraction and mssbauer spectroscopy to confirm the identity of this maghemite and compared its magnetic hysteresis, high temperature magnetization, low temperature thermal demagnetization, and low temperature susceptibility with those of the original preheated magnetite. Such quickly oxidized maghemite by heating to high temperature implies some types of maghemite formed in certain natural condition can carry a thermal remnant magnetization (TRm). Four types of maghemite were characterized and discussed according to their thermal stability. Among them, partially stable and fully thermally stable maghemite after heating should possess capability of carrying TRm. There is possibly a compensation of synthetizing maghemite between heatin

关键词： maghemite paleomagnetism environmental magnetism magnetic mineral thermal stability TRm

Characterization of the Tomato Prosystemin Promoter:Organ-specific Expression,Hormone Specificity and methyl Jasmonate Responsiveness by Deletion Analysis in Transgenic Tobacco Plants

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Journal of Integrative Plant Biology 2012年第1期54卷 15-32页

作者： Hamlet Avilés-Arnaut john paul Délano-Frier Center of Research and Advanced Studies (Cinvestav) at Irapuato:Unit for Plant Biotechnology and Genetic Engineering

Tomato systemin is a bioactive peptide that regulates the systemic activation of wound-responsive genes. It is released from its 200 amino acid precursor called prosystemin. Initial tissue-localization and hormone-induced expression assays indicated that the tomato prosystemin gene （SIPS） accumulates mainly in floral tissues and in response to exogenous abscisic acid and methyl jasmonate （meJA） treatments, respectively. Later, the promoter regions of the PS gene in tomato （Solanum lycopersicum L. cv. Castlemart）, pepper （Capsicum annuum） and potato （Solanum tuberosum） were isolated and an in silico analysis of the SIPS promoter revealed an over-representation of stress- and meJA-responsive motifs. A subsequent 5＇ deletion analysis of the SIPS promoter fused to the/^-glucuronidase reporter （GUS） gene showed that the -221 to ＋40 bp proximal SIPS promoter region was sufficient to direct the stigma, vascular bundle-specific and meJA-responsive expression of GUS in transgenic tobacco plants. Important ***-specific, light- and meJA-responsive cis-elements were also present in this region. These findings provide relevant information regarding the transcriptional regulation mechanisms of the SIPS promoter operating in transgenic tobacco plants. They also suggest that its Ussue-specificity and inducible nature could have wide applicability in plant biotechnology.

关键词： cis-regulatory elements flower specific jasmonic acid methyl jasmonate promoter analysis prosystemin wound-responsive genes.

Development and evaluation of an individual tree growth and yield model for the mixed species forest of the Adirondacks Region of New York, USA

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Forest Ecosystems 2017年第1期4卷 66-82页

作者： Aaron Weiskittel Christian Kuehne john paul m.tague mike Oppenheimer University of maine School of Forest Resources Orono ME 04469 USA. Rayonier Forest Research Center Yulee FL 32041 USA Rayonier Foresl Resources Fernandina Beach FL 32035 USA. University of maine 5755 I Nutting Hall Orono ME 04469-5755 USA.

Background： Growth and yield models are important tools for forest planning. Due to its geographic location, topology, and history of management, the forests of the Adirondacks Region of New York are unique and complex. However, only a relatively limited number of growth and yield models have been developed and/or can be reasonably extended to this region currently. methods： in this analysis, 571 long-term continuous forest inventory plots with a total of 10 - 52 years of measurement data from four experimental forests maintained by the State University of New York College of Environmental Science and Forestry and one nonindustrial private forest were used to develop an individual tree growth model for the primary hardwood and softwood species in the region. Species-specific annualized static and dynamic equations were developed using the available data and the system was evaluated for long-term behavior. Results： Equivalence tests indicated that the Northeast Variant of the Forest Vegetation Simulator （FVS-NE） was biased in its estimation of tree total and bole height, diameter and height increment, and mortality for most species examined. In contrast, the developed static and annualized dynamic, species-specific equations performed quite well given the underlying variability in the data. Long-term model projections were consistent with the data and suggest a relatively robust system for prediction. Conclusions： Overall, the developed growth model showed reasonable behavior and is a significant improvement over existing models for the region. The model also highlighted the complexities of forest dynamics in the region and should help improve forest planning efforts there.

关键词： Individual tree growth model mixed species Forest vegetation simulator

Natural regeneration responses to thinning and burning treatments in ponderosa pine forests and implications for restoration

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Journal of Forestry Research 2022年第3期33卷 741-753页

作者： Tzeidle N.Wasserman Amy E.m.Waltz john paul Roccaforte Judith D.Springer Joseph E.Crouse Ecological Restoration Institute Northern Arizona UniversityP.O.Box 15017FlagstaffAZ86011-5017USA

Understanding naturally occurring pine regeneration dynamics in response to thinning and burning treatments is necessary not only to measure the longevity of the restoration or fuels treatment,but also to assess how well regeneration meets forest sustainability guidelines and whether natural regeneration is sufficient for maintaining a sustainable forest structure and composition.A synthesis review was carried out on the effects of mechanical thinning and prescribed burn treatments on natural pine regeneration response in frequent-fire ponderosa pine forests across the western United *** focus was on site-specific variability in pine regeneration dynamics,temporal trends in regeneration presence and abundance,and response to treatment as described in the current literature using 29 studies that met our evidence-based review *** showed that the effects of thinning and burning treatments on regeneration depended on time since *** thinning,prescribed burning,and thinning plus burn treatments all increased seedling density,but there was high variability among sites and *** were mixed results in the short-term(m studies(>20 years)concluded that stands can return to pre-treatment densities in terms of total trees per hectare and forest floor duff levels when there are no maintenance treatments *** studies showed the average ponderosa pine seedling presence,survival and growth found in today’s forests to be at a high density;this combined with missed fire cycles could contribute to future fire risk and reduce the efficacy of maintaining fuel reduction goals.

关键词： Regeneration Ponderosa pine Frequent-fire Treatments Thinning Burning

Numerical modeling of sediment flushing from Lewis and Clark Lake

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International Journal of Sediment Research 2013年第2期28卷 182-193页

作者： Jungkyu AHN Chih Ted YANG paul m.BOYD Daniel B.PRIDAL john I.REmUS Civil and Environmental Engineering Department Seoul National UniversitySeoulRepublic of Korea Research Fellow Water Resources and Director of Hydroscience and Training Center Civil and Environmental Engineering DepartmentColorado State UniversityFort CollinsCOUSA80526 Borland Professor U.S.Army Corps of Engineers OmahaNebraskaUSA Hydraulic Engineer Sedimentation and Channel Stabilization Section U.S.Army Corps of EngineersOmahaNebraskaUSA Chief

Lewis and Clark Lake is located on the main stream of the missouri *** reservoir is formed behind Gavins Point dam near Yankton,South Dakota,*** Lewis and Clark Lake reach extends about 40 km from the Gavins Point *** reservoir delta has been growing since the closure of Gavins Point dam in 1955 and has resulted in a 21%reduction of storage within the maximum pool of the *** several sediment management methods,drawdown flushing has been recommended as a possible management *** engineering viability of removing sediments deposited in the lake should be examined by numerical modeling before implementing a drawdown ***4 was used for this study and calibrated by using measured data from 1975 to *** cross-section changes and amount of flushed sediment were predicted with four hypothetical flow *** flushing efficiencies of all scenarios were estimated by comparing the ratios between water consumption and flushed sediment during flushing.

关键词： Drawdown flushing Flushing efficiency GSTARS computer model Reservoir sedimentation Sediment transport Lewis and Clark Lake

Analyzing machine learning models to accelerate generation of fundamental materials insights

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npj Computational materials 2019年第1期5卷 858-866页

作者： mitsutaro Umehara Helge S.Stein Dan Guevarra paul F.Newhouse David A.Boyd john m.Gregoire Joint Center for Artificial Photosynthesis California Institute of TechnologyPasadenaCA 91125USA Future mobility Research Department Toyota Research Institute of North AmericaAnn ArborMI 48105USA

machine learning for materials science envisions the acceleration of basic science research through automated identification of key data relationships to augment human interpretation and gain scientific understanding.A primary role of scientists is extraction of fundamental knowledge from data,and we demonstrate that this extraction can be accelerated using neural networks via analysis of the trained data model itself rather than its application as a prediction *** neural networks excel at modeling complex data relationships in multi-dimensional parameter spaces,such as that mapped by a combinatorial materials science *** a performance metric in a given materials space provides direct information about(locally)optimal materials but not the underlying materials science that gives rise to the variation in *** building a model that predicts performance(in this case photoelectrochemical power generation of a solar fuels photoanode)from materials parameters(in this case composition and Raman signal),subsequent analysis of gradients in the trained model reveals key data relationships that are not readily identified by human inspection or traditional statistical *** interpretation of these key relationships produces the desired fundamental understanding,demonstrating a framework in which machine learning accelerates data interpretation by leveraging the expertize of the human *** also demonstrate the use of neural network gradient analysis to automate prediction of the directions in parameter space,such as the addition of specific alloying elements,that may increase performance by moving beyond the confines of existing data.

关键词： neural prediction desired

Effect of Oil Spillage on the Growth of Cassava in Niger Delta Region of Nigeria

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Effect of Oil Spillage on the Growth of Cassava in Niger Del...

作者： Akpang paul john 沈阳农业大学

学位级别：硕士

Cassava has grown and developed from being a minor crop to becoming a major crop consumed by several homes in the ***,the incessant oil spillage and crude oil pollution has increased the concern on the productivity of this crop in the Niger Delta *** the research was aimed at providing empirical evidence on the actual impact of crude oil spillage in the Niger delta on the soil and productivity of cassava *** specific objectives of the study were to assess the socio-economic characteristics of cassava producers in the Niger Delta,evaluate the effects of the crude oil spill on the soil properties and cassava yield in area,compare the difference in yield with communities not affected by oil spill,analyses the efforts of oil companies in the communities and make policy *** study adopted a mixed research approach that employed questionnaire to gain insight from farmers on the effect of oil spillage on their productivity and a lab test of soil sample for examining the effect of oil spill on soil *** m ai n results ar e as fo l l o ws :（1）The study found a net margin of N27,218.17 and N18,382.17 per cassava producer in non-oil and oil spill areas in the Niger Delta Region,*** spills have resulted in a 31% fall in cassava producer *** to the test of difference,there is a significant difference of 8,836 in cassava producers’ net margin（***）between non-oil and oil spill locations.（2）For oil spill and non-oil spill communities,the yearly fixed cost and total variable cost per hectare cassava grower were N6,799.15 and N19,268.68,***,frying pans,diggers,and cutlasses were the most important fixed costs in cassava production,accounting for 34.03%,11.57%,10.82%,and 9.64% of total fixed costs,***,fertilizers,planting supplies,transportation,and processing were the greatest operational cost components,accounting for 22.49%,20.92%,15.76%,14.80%,and 16.24% of total vari

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关于《〈垄断资本〉一些理论含义》的最后通信

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政治经济学季刊 2024年第1期3卷 117-133页

作者：保罗·巴兰保罗·斯威齐张雪琴当代著名马克思主义中共中央党校(国家行政学院)马克思主义学院

“最后通信”系保罗·巴兰和保罗·斯威齐于1964年2月底至3月初的往来通信,其内容主要同垄断资本缺失的理论章《一些理论含义》有关。这一章由巴兰于1962年起草,那时他们正在从事《垄断资本》的出版修订工作。关于《一些理论含义》的讨... 详细信息

“最后通信”系保罗·巴兰和保罗·斯威齐于1964年2月底至3月初的往来通信,其内容主要同垄断资本缺失的理论章《一些理论含义》有关。这一章由巴兰于1962年起草,那时他们正在从事《垄断资本》的出版修订工作。关于《一些理论含义》的讨论因巴兰于1964年3月26日溘然长逝而被迫中断。这些通信由约翰·贝拉米·福斯特编辑注释并首次公开发表~((1))。

关键词：理论含义垄断资本巴兰修订工作通信