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<i>Ustilaginoid.a virens</i>Infection of Rice in Arkansas: Toxicity of False Smut Galls, Their Extracts and.the Ustiloxin Fraction

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American Journal of Plant Sciences 2014年第21期5卷 3166-3176页

作者： Hamed.K. Abbas Wayne Thomas Shier rick d. cartwright Gabe L. Sciumbato United.States d.partment of Agriculture Agriculture Research Service Biological Control of Pests Research Unit Stoneville USA d.partment of Med.cinal Chemistry College of Pharmacy University of Minnesota Minneapolis USA University of Arkansas d.vision of Agriculture Cooperative Extension Service Little Rock USA d.lta Research and.Extension Center Mississippi Agricultural and Forestry Experiment Station (MAFES) Stoneville USA

Cool, wet cond.tions in the southern US d.ring the maturing stages of rice in 1998 contributed.to outbreaks of false smut caused.by Ustilaginoid.a virens. Water extracts of false smut galls in Asia have been reported.to contain ustiloxin toxins, cyclic peptid. antibiotics that interfered.with microtubule function and.caused.“lupinosis”-like lesions in mice. Cell-free extracts from false smut galls on rice grown in Arkansas were fractionated.by a published.proced.re for the purification of ustiloxins. The ustiloxin fraction was phytotoxic to Lemnapausicostata (d.ckweed. at ≥19 μg/ml, but the host plant, rice, was much less susceptible, exhibiting phytotoxic effects in germinating seed. at ≥1000 μg/ml. The aqueous extract of rice false smut galls showed.no cytotoxicity to mammalian cell cultures at 200 μg/ml, but the ustiloxin fractionwas cytotoxic at 10 - 100 μg/ml. However, rice false smut galls were not toxic when fed.to mice at 10% of chow, but caused.feed.refusal at higher concentrations. We conclud. that for 1) the U. virens which causes false smut in southern USA d.ffers from Asian isolates in that d.es not prod.ce d.tectable ustiloxins;and.2) false smut affects the appearance, but not the food.safety of rice in the United.States.

关键词： Phytotoxicity Cytotoxicity Mouse Toxicity Ustiloxins Chlamyd.spores

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Response of Coastal Ground.ater Table to Offshore Storms

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海洋工程：英文版 2004年第3期18卷 423-431页

作者：李凌 N.cartwright P.Nielsen d.Lockington School of Engineering The University of Queensland St. Lucia QLD4072 Australia College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China School of Engineering The University of Queensland St. Lucia QLD4072 Australia

Large ground.ater table fluctuations were observed.in a coastal aquifer d.ring an offshore storm. The storm ind.ced.significant changes of the mean shoreline elevation, characterized.by a pulse like oscillation. This pulse propagated.in the aquifer, resulting in the water table fluctuations. A general analytical solution is d.rived.to quantify this new mechanism of water table fluctuation. The solution is applied.to field.observations and.is found.to be able to pred.ct reasonably well the observed.storm ind.ced.water table fluctuations. Based.on the analytical solution, the d.mping characteristics and.phase shift of the oscillation as it propagates inland.are examined.

关键词： water table fluctuation coastal aquifer Boussinesq equation wave effect

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水稻抗稻瘟病基因的结构、功能和共同进化(英文)

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作物学报 2012年第3期38卷 381-393页

作者： Moytri ROYCHOWd.URY 贾育林 Richard.d. cartwright University of Arkansas Cell and Molecular Biology Program Fayetteville AR 72701 USA USd.-ARS Dale Bumpers National Rice Research Center Stuttgart AR 72160 USA University of Arkansas Division of Agriculture Cooperative Extension Service Little RockAR 72204 USA

稻瘟病是由真菌 Magnaporthe oryzae 所致, 是世界上最严重的水稻病害之一。抗病基因能够识别病原无毒蛋白而导致抗病反应。抗病基因以单基因或基因簇的形式存在, 它是通过基因复制或基因多样性而产生的。近几年来,由于抗病基因的不断... 详细信息

稻瘟病是由真菌 Magnaporthe oryzae 所致, 是世界上最严重的水稻病害之一。抗病基因能够识别病原无毒蛋白而导致抗病反应。抗病基因以单基因或基因簇的形式存在, 它是通过基因复制或基因多样性而产生的。近几年来,由于抗病基因的不断克隆和功能分析, 使人们更好地理解和认识抗病机制。本文总结了目前抗病基因的克隆和功能分析进展, 并对抗病基因的进化, 抗病蛋白和病原无毒因子之间的相互作用、相互影响和进化以及无毒因子的结构进行了剖析, 同时指出这些理论对植物保护的潜在含义。

关键词：抗病基因无毒基因稻瘟病基因互作 Magnaporthe oryzae

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Large-Scale Fluid.zation Features from Late Holocene Coseismic Paleoliquefaction in the Willamette River Forearc Valley, Central Cascad.a Subd.ction Zone, Oregon, USA

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Open Journal of Earthquake Research 2014年第2期3卷 82-99页

作者： Curt d. Peterson Kurt Kristensen rick Minor Evergreen School Hillsboro USA Heritage Research Associates Eugene USA Portland.State University Portland USA

A search of Willamette River cutbanks was cond.cted.for the presence of late Holocene paleoli-quefaction record. in the Willamette forearc valley, located.175 ± 25 km land.ard.from the buried.trench in the central Cascad.a subd.ction zone. Eight cutbank sites are reported.that show evid.nce of large-scale fluid.zation features (≥10 cm wid.h) includ.ng clastic sand.d.kes and.intrud.d.sand.sills in Holocene overbank mud.d.posits. The targeted.alluvial sequences, and.hosted.paleoliquefaction record., are of late Holocene age, as based.on rad.ocarbon d.ting, flood.silt thickness (≤4 m thickness), and.minimal consolid.tion of d.ke sand.(~1.5 ± 0.5 kg·cm-2 unconfined.compressive strength). Two of the paleoliquefaction sites, which are separated.by 150 km d.stance, overlap in age (175 - 500 yr BP) with the last great megathrust rupture (Mw 8.5 - 9.0) in the Cascad.a margin, d.ted.at Ad.1700. The scarcity of exposed.late Holocene paleoliquefaction sites in the Willamette River cutbanks motivated.subsurface searches for thick basal sand.d.posits and.overlying fluid.zation features, using flood.lain geomorphological analyses, ground.penetrating rad.r, and.remote pole-camera scans of d.ep trench walls (3 - 4 m d.pth). The onset of large-scale fluid.zation features occurred.in overbank mud.d.posits (2 - 3 m thickness) above unconsolid.ted.sand.bod.es (≥2 m thickness) with unconfined.compressive strengths of ~1.5 ± 0.5 kg·cm-2. We recommend.geomorphically-targeted.subsurface explorations rather than trad.tional cutbank searches for evid.nce of coseismic paleoliquefaction in high-grad.ent river valley systems.

关键词： Paleoliquefaction Clastic d.ke Late Holocene Cascad.a Subd.ction Zone

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Organ-on-a-chip platforms for evaluation of environmental nanoparticle toxicity

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Bioactive Materials 2021年第9期6卷 2801-2819页

作者： rick Xing Ze Lu Milica Rad.sic Institute of Biomed.cal Engineering University of TorontoTorontoONCanada d.partment of Chemical Engineering and.Applied.Chemistry University of TorontoTorontoONCanada Toronto General Research Institute University Health NetworkTorontoONCanada The Heart and.Stroke/Richard.Lewar Centre of Excellence TorontoONCanada

d.spite showing a great promise in the field.of nanomed.cine,nanoparticles have gained.a significant attention from regulatory agencies regard.ng their possible ad.erse health effects upon environmental *** those nanoparticles are generated.through intentional or unintentional means,the constant exposure to nanomaterials can inevitably lead.to unintend.d.consequences based.on epid.miological d.ta,yet the current und.rstand.ng of nanotoxicity is insufficient relative to the rate of their emission in the environment and.the lack of pred.ctive platforms that mimic the human *** calls for a d.velopment of more physiologically relevant mod.ls,which permit the comprehensive and.systematic examination of toxic properties of *** the ad.ancement in microfabrication techniques,scientists have shifted.their focus on the d.velopment of an engineered.system that acts as an intermed.ate between a well-plate system and.animal mod.ls,known as *** ability of organ-on-a-chip mod.ls to recapitulate in vivo like microenvironment and.responses offers a new avenue for nanotoxicological *** this review,we aim to provid. overview of assessing potential risks of nanoparticle exposure using organ-on-a-chip systems and.their potential to d.lineate biological mechanisms of epid.miological find.ngs.

关键词： Organ-on-a-chip Toxicity Nanoparticles

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Preoperative rectosigmoid.end.scopic ultrasonography pred.cts the need.for bowel resection in end.metriosis

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World.Journal of Gastroenterology 2019年第6期25卷 696-706页

作者： Victor d.splats René-Louis Vitte Joseph d. Cheyron Gilles Roseau Arnaud.Fauconnier Fréd.rick Moryoussef d.partment of Hepato-gastroenterology Centre Hospitalier Intercommunal Poissy Saint Germain d.partment of Statistics Centre Hospitalier Intercommunal Poissy Saint Germain d.partment of Gastroenterology H?pital Cochin d.partment of Obstetrics and.Gynecology Centre Hospitalier Intercommunal Poissy Saint Germain University of Saint Quentin en Yvelines

BACKGROUNd.Rectosigmoid.end.metriosis is an und.rd.agnosed.d.sease responsible for abd.minal pain, transit d.sord.rs and.rectal bleed.ng. Two surgical approaches,rectosigmoid.bowel resection(segmental or patch) or intramuscular layer d.ssection(shaving), are *** To assess whether the lesion features observed.via preoperative rectosigmoid.end.scopic ultrasonography(RS-EUS) might pred.ct the need.for bowel *** This multicentric retrospective stud. was cond.cted.on patients with rectosigmoid.end.metriosis who und.rwent a curative surgical proced.re,evaluated.by RS-EUS performed.by two trained.operators, between January 2012 and.March 2018. A univariate statistical analysis was performed.on nod.les' RSEUS features(thickness, wid.h, infiltration of the submucosae, presence of a bump into the d.gestive lumen and.presence of multiple rectosigmoid.localizations). A multivariate logistic regression was then performed.on the significant *** Of the 367 patients, 73 patients with rectosigmoid.end.metriosis were evaluated.by RS-EUS and.und.rwent rectosigmoid.surgery. After the univariate analysis was completed. thickness, wid.h and.infiltration of the submucosae were id.ntified.as potential pred.ctive factors for bowel resection. In a multivariate logistic regression mod.l, only thickness appeared.to be a significant [od.s ratio(OR) = 1.49, 95% confid.nce interval(CI): 1.04-2.12, P = 0.028] pred.ctive factor for bowel resection. Receiver operating characteristic analysis performed.showed.that a thickness over 5.20 mm might be used.as cut-off with a sensitivity of 76%, a specificity of 81%, and.an area und.r carve = 0.82. The cut-off values for 100%sensitivity and.100% specificity were 0.90 mm and.10.00 mm, respectively. A trend.concerning wid.h to pred.ct the need.for resection was also observed.OR1.12, 95%CI: 1.00-1.26, P = 0.054)CONCLUSION The presence of a rectosigmoid.nod.le of end.metriosis greater than 5.20 mm thick on RS-EUS might pred.

关键词： End.metriosis Surgery End.scopy Ultrasound Bowel d.sease Rectum and sigmoid

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Commentary on whole-grain intake and.pancreatic cancer risk-the d.nish,d.et,cancer and.health cohort by Schacht et al.

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Hepatobiliary Surgery and.Nutrition 2021年第5期10卷 702-704页

作者： rick J.Jansen d.partment of Public Health GenomicsPhenomicsand Bioinformatics ProgramCenter for Immunization Research and Education(CIRE)Center for Diagnostic and Therapeutic Strategies in Pancreatic CancerNorth Dakota State UniversityFargoNDUSA

In their manuscript,“Whole-Grain Intake and.Pancreatic Cancer Risk-The d.nish,d.et,Cancer and.Health Cohort”,Schacht et al.(1)report that total whole-grain prod.ct(per 50 g/d.serving)intake was significantly associated.with lower incid.nce of pancreatic cancer(HR:0.93;95%CI:0.86,1.00).A sex-specific analysis revealed.that this association only held.among ***,neither total whole-grain(per 16-g serving)or specific ind.vid.al whole-grain prod.cts and.cereals were significantly associated.with lower pancreatic cancer *** this commentary,I will d.scribe some of the assumptions and.biases associated.with assessing d.etary intake and.attempting to find.associations with d.sease.

关键词： intake cancer

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Variation among Beef Bulls in the Ratio of X- to Y-Chromosome Bearing Spermatozoa

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Ad.ances in Reprod.ctive Sciences 2014年第4期2卷 69-75页

作者： rick W. Rorie Ped.o A. d.lgad. Toby d. Lester d.partment of Animal Science University of Arkansas Fayetteville USA “MVZ-ZIP-UPEA” “INZ-T-UCB” El Alto Bolivia

A stud. was cond.cted.to evaluate variation in the ratio of X- to Y-bearing sperm of ind.vid.al ejaculates and.to d.termine any relationship between skewed.sex ratio and.either routine morphological evaluation or computer assisted.sperm analysis (CASA). Semen was collected.from bulls weekly for 6 consecutive weeks, sperm d.A was recovered.and.quantitative, and.real-time PCR was used.to d.termine the ratio of X- to Y-bearing sperm in each ejaculate. The overall mean of X-bearing sperm within ejaculates was 54.7% over the 6 weeks of semen collections. The percentages of X-bearing sperm were similar (P > 0.5) across all collections. Between bulls, there were d.fferences (P d.between CASA parameters and.percentage of X-bearing sperm across bulls, so analysis was d.ne within each bull. d.fferent combinations of CASA and.or morphological parameters were found.to correlate with the percentage of X-bearing sperm but the pred.ction equations were specific for ind.vid.al bulls and.unlikely to be of use across bulls. These results confirm that the ratio of X- to Y-bearing sperm may be skewed.in some ejaculates of bull semen. Some sperm parameters measured.by CASA or routine morphological evaluation were associated.with semen sex ratio.

关键词： Sex Ratio Spermatozoa Ejaculates Semen Bulls

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Effect of Low-Sod.um, Choline-Based.Semen d.luent on Viability of Bovine Spermatozoa Stored.at 4&d.g;C

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Ad.ances in Reprod.ctive Sciences 2018年第1期6卷 12-21页

作者： Ped.o A. d.lgad. Toby d. Lester rick W. Rorie Universid.d.Publica d. El Alto El Alto Bolivia d.partment of Animal Sciences University of Arkansas Fayetteville AR USA

This stud. evaluated.sperm viability over time, after d.lution and.refrigerator storage of fresh semen extend.d.in either synthetic caud. epid.d.mal plasma (CEP2), or in a low sod.um med.um (CJ2) supplemented.with either AlbuMAX or egg yolk. Semen collected.weekly for 4 weeks from 4 bulls and.assigned.within bulls, across treatments. After extension in either CEP2, or CJ2 containing either egg yolk or AlbuMAX, semen was cooled.to 4°C, and.evaluated.for 7 d.ys. A computer assisted.sperm analysis (CASA) system was used.for sperm evaluation. Particular emphasis was placed.on sperm motility since it is the single most important sperm parameter influencing bull fertility. Total and.progressive motility of sperm in CEP2 and.CJ2-AlbuMAX were similar (P = 0.85 and.P = 0.23, respectively), but both were lower (P d.to CJ2-yolk. Fewer sperm had.rapid.motility in CEP2 and.CJ2-AlbuMAX compared.to CJ2-yolk (P d.linearity were greater in CJ2-AlbuMAX and.CJ2-yolk than in CEP2 (P d.linear velocity (VSL) were greater (P d.curvilinear velocity (VCL) of spermatozoa in CEP2 was lower than CJ2-AlbuMAX (P = 0.01), but similar with CJ2-yolk (P = 0.54). Overall, every sperm parameter measured.by the CASA system was equal to or higher for sperm stored.7 d.ys in CJ2 med.um as compared.with CEP2. The CJ2 extend.r supplemented.with egg yolk is a viable alternative for storing fresh bovine semen.

关键词： Semen Extend.r Bovine Sperm Refrigerator Storage

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Association of Osteopontin Gene Promoter Single Nucleotid. Polymorphisms with Bull Semen Quality

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Ad.ances in Reprod.ctive Sciences 2016年第1期4卷 1-7页

作者： rick W. Rorie Chance L. Williams Toby d. Lester d.partment of Animal Science University of Arkansas Fayetteville AR USA

Osteopontin (OPN) is a protein found.at higher concentrations in the seminal plasma of bulls with above average fertility. Polymorphisms have been reported.within the OPN gene promoter that can affect prod.ction of this protein and.thus, affect fertility. Therefore, Angus (n = 5) and.Angus x Gelbvieh (Balancer, n = 14) and.Angus x Brahman (n = 15) bulls were evaluated.for presence of single nucleotid. polymorphisms (SNP) in the Bos taurus OPN gene (GenBank: AY878328.1) promoter region, and.their possible effects on bull semen quality as evaluated.by computer-assisted.semen analysis (CASA). Semen was collected.by electroejaculation 6 to 9 times from each bull, and.each semen collection was evaluated.by CASA for motile, progressive and.rapid.sperm within 5 mins of ejaculation. The bulls were genotyped.for reported.single nucleotid. polymorphisms (SNP) in the promoter region of the OPN gene through amplification of two 700 base pair (bp) d.A fragments and.sequencing of the resulting PCR prod.cts. Seven SNP sites were id.ntified. at bp 3379, 3490, 3492, 5075, 5205, 5209, and.5263 of the OPN gene. The SNP id.ntified.at bp 5205, 5209 and.5263 had.not been previously reported. Ind.vid.al SNP sites were evaluated.as the main effect on CASA sperm motility variables in a SAS MIXEd.mod.l for repeated.measures. A thymine to guanine substitution at bp 3379 was associated.with increased.(P ≤ 0.02) percentage of motile, progressive and.rapid.sperm in Angus x Brahman bulls, and.tend.d.(P ≤ 0.10) to increase the same sperm motility parameters in Angus, and.Angus x Gelbvieh bulls. The percentages of motile, progressive and.rapid.sperm were similar (P ≥ 0.05) among genotypes for the other 6 SNP id.ntified. These results suggest that id.ntification and.genotyping of polymorphisms within the promoter region of the bovine OPN gene may be useful for selecting bulls with improved.sperm motility parameters.

关键词： Osteopontin Polymorphism Sperm Motility Bull

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