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Rare-earth and trace elements and hydrogen and oxygen isotopic compositions of Cretaceous kaolinitic sediments from the Lower Benue Trough, Nigeria: provenance and paleoclimatic significance

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Acta Geochimica 2019年第3期38卷 350-363页

作者： anthony T.Bolarinwa Sunday O.Idakwo david L.Bish department of Geology University of Ibadan department of Earth Sciences Kogi State University department of Geological Sciences Indiana University

This study evaluated the Cretaceous(Campanian–Maastrichtian) kaolinitic sediments of the Ajali/Mamu and Enugu/Nkporo Formations from the Lower Benue Trough of Nigeria. A combined method of inductively coupled plasma–mass spectrometry and isotope ratio mass spectrometry was used to investigate trace and rareearth element geochemistry and hydrogen and oxygen isotopic compositions. These data were then used to infer the sediments' provenance and paleoclimatic conditions during their deposition. The sediments contained low concentrations of most trace elements, with the exceptions of Zr(651–1352 ppm), Ba(56–157 ppm), V(38–90 ppm),and Sr(15.1–59.6 ppm). Average values of Co and Ni were1.5 and 0.7 ppm, respectively. Trace and rare earth element values were lower than corresponding values for upper continental crust and Post-Archean Australian Shale, with the exception of Zr. The samples showed only slight light rare-earth enrichment and nearly flat heavy rare-earth depletion patterns, with negative Eu and Tm anomalies,typical of felsic sources. Geochemical parameters such as La/Sc, Th/Sc, and Th/Co ratios support that the kaolinitic sediments were derived from a felsic rock source, likely deposited in an oxic environment.^(18 )O values ranged from+ 15.4 to + 21.2% for the investigated samples, consistent with a residual material derived from chemicalweathering of felsic rock and redeposited in a sedimentary basin(typical values of + 19 to + 21.2%). While in the basin, the sediments experienced extended interactions with meteoric water enriched in d d and d16 O. However,the variation in d d and d16 O values for the investigated samples is attributed to the high temperature of formation(54–91 °C). The d d and d^(18 )O values suggest that the sediments, although obtained from different localities within the Lower Benue Trough, formed under similar hot,tropical climatic conditions.

关键词： Rare-earth and trace elements Oxygen/ hydrogen isotopic composition Kaolinitic sediments Lower Benue Trough Nigeria

Placental accommodations for transport and metabolism during intra-uterine crowding in pigs

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Journal of Animal Science and Biotechnology 2015年第2期6卷 163-176页

作者： Jeffrey L Vallet anthony K Mc Neel Jeremy R Miles Bradley A Freking U.S. department of Agriculture Agricultural Research Service U.S. Meat Animal Research CenterState Spur 18D Clay Center NE 68933 USA

Litter size and birth weights are limited by uterine capacity, defined as the ability of the uterus to maintain the appropriate development of some number of conceptuses. Uterine capacity is the result of the combined effects of uterine, placental and embryo/fetal function. The number of living conceptuses that the uterus is capable of supporting is greater during early gestation compared to later gestation. Plots of log fetal weight versus log placental weight also indicate that fetal weights are less sensitive to reduced placental weight （and therefore reduced intrauterine space） in early gestation compared to late gestation. However, even in late gestation, mechanisms still exist that maintain fetal growth when the size of the placenta is reduced. One such mechanism is likely to be improved development of the folded placental-epithelial/maternal-epithelial bilayer. Fold depth, and therefore the maternal fetal interactive surface, increases as gestation advances and is greater in placenta from smal fetuses. On the fetal side of the placenta, the epithelial bilayer is embedded in stromal tissue. Glycosaminoglycans are major components of stroma, including hyaluronan and heparan sulfate. Hyaluronidases and heparanases are present within placental tissues, and likely play roles in modification of stromal components to facilitate fold development. Glycosaminoglycans are polymers of forms of glucose （glucosamine, glucuronic acid, iduronic acid） suggesting that glycosaminoglycan synthesis may compete with the glucose needs of the developing fetus. Pig conceptuses are fructogenic, such that a substantial portion of glucose transferred from mother to fetus is converted to fructose. Fructose is an intermediate product in the synthesis of glucosamine from glucose, and glucosamine is linked to regulation of trophoblast cell proliferation through regulation of mTOR. These findings suggest a link between glucose, fructose, glucosamine synthesis, GAG production, and placental m

关键词： Glycosaminoglycans Nutrient transport Placenta

Population increase and changes in behavior and morphology in the Critically Endangered Redonda ground lizard(Pholidoscelis atratus)following the successful removal of alien rats and goats

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Integrative Zoology 2021年第3期16卷 379-389页

作者： Colin M.dONIHUE Jennifer C.dALTRY Shanna CHALLENGER anthony HERREL UMR 7179 C.N.R.S/M.N.H.N. Département Adaptations du VivantParisFrance department of Biology Washington University in St.LouisSt.LouisMissouriUSA Fauna&Flora International David Attenborough BuildingPembroke StreetCambridgeUK department of Environment St.John’sAntigua Environmental Awareness Group St.John’sAntigua

Redonda is a small volcanic Caribbean island that is home to at least 4 endemic lizard species,including the Critically Endangered ground lizard(Pholidoscelis atratus).Black rats(Rattus rattus)and domestic goats(Capra hircus)were introduced to the island at some time after its discovery by Europeans in the late *** had a devastating effect on the island,resulting in the loss of nearly all trees and most of the ground *** count surveys of *** in 2012 indicated low densities,and the invasive rats were observed hunting and preying on the *** populations of rats and goats were successfully removed in 2017 as part of an ecological restoration program,and native vegetation and invertebrate populations have increased rapidly *** surveys in 2017,2018,and 2019 show the lizard population has increased by more than *** 2017,as rats and goats were being removed,we evaluated the morphology and escape behavior of this species and repeated these measurements 1 year *** observed that *** had become bolder,with a reduced flight *** also detected changes in limb morphology related to locomotion and suggest possible explanations that will need to be further investigated in the *** results show how the removal of invasive species can rapidly affect lizard population recovery and behavior,potentially restoring island ecosystems to their pre-human interference dynamics.

关键词： Antigua and Barbuda Caribbean conservation endangered species invasive alien species island biology Lesser Antilles pest removal

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导读:发展城市绿色交通的合理方法

城市交通 2017年第3期15卷 7-8,35页

作者： anthony d May 张斯阳英国利兹大学中国城市规划设计研究院

经济繁荣对城市发展至关重要。欧洲城镇化地区拥有70%的人口,却贡献80%的经济产出。与此同时,城市交通也引发诸多问题。以欧洲为例,城镇化地区分担了80%交通拥堵造成的经济损失、70%的有毒物质污染以及40%的道路死亡,同时对CO2排放的贡... 详细信息

经济繁荣对城市发展至关重要。欧洲城镇化地区拥有70%的人口,却贡献80%的经济产出。与此同时,城市交通也引发诸多问题。以欧洲为例,城镇化地区分担了80%交通拥堵造成的经济损失、70%的有毒物质污染以及40%的道路死亡,同时对CO2排放的贡献率达14%。欧洲议会认识到问题的严重性,不能仅停留在城市层面进行管理,议会与各成员国协同工作,鼓励城市摸索新型交通规划模式,即发展可持续城市机动性规划（Sustainable Urban Mobility Plans,SUMPs）。

关键词：绿色交通有毒物质人口年增长率协同工作规划模式欧洲议会评价指标预算计划可达性自我评估

Exchange-Correlation Functional Comparison of Electronic Energies in Atoms Using a Grid Basis

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Journal of Applied Mathematics and Physics 2022年第11期10卷 3392-3407页

作者： anthony d. Ryan Andres Gama Frank Felerski William d. Parker department of Mathematics and Physics University of Wisconsin-Parkside Kenosha WI USA

Calculation of total energies of the electronic ground states of atoms forms the basis for the frozen-core pseudopotentials used in atomistic calculations of much larger scale. Reference values for these energies provide a benchmark for the validation of new software to calculate such potentials. In addition, basic atomic-scale electronic properties such as the (first) ionization energy provide a simple check on the approximation used in the calculation method. We present a comparison of the total energies and ionization energies of atoms Z = 1 - 92 calculated in density functional theory with several levels of exchange-correlation functional and the Hartree-Fock method, comparing ionization energies to experiment. We also investigate the role of relativistic treatment on these energies.

关键词： density Functional Theory Hartree-Fock Theory Electronic Energies Exchange-Correlation Potential Exchange and Correlation Functional Ionization Energy

Ground-Based LidAR Improves Phenotypic Repeatability of Above-Ground Biomass and Crop Growth Rate in Wheat

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Plant Phenomics 2020年第1期2卷 138-148页

作者： david M.deery Greg J.Rebetzke Jose A.Jimenez-Berni anthony G.Condon david J.Smith Kathryn M.Bechaz William d.Bovill CSIRO Agriculture and Food CanberraACTAustralia CSIRO Agriculture and Food YancoNSWAustralia NSW department of Primary Industries YancoNSWAustralia

Highly repeatable,nondestructive,and high-throughput measures of above-ground biomass(AGB)and crop growth rate(CGR)are important for wheat improvement *** study evaluates the repeatability of destructive AGB and CGR measurements in comparison to two previously described methods for the estimation of AGB from LidAR:3d voxel index(3dVI)and 3d profile index(3dPI).Across three field experiments,contrasting in available water supply and comprising up to 98 wheat genotypes varying for canopy architecture,several concurrent measurements of LidAR and AGB were made from jointing to *** correlations at discrete events between AGB and the LidAR-derived biomass indices were significant,ranging from 0.31(Pding confidence in the LidAR indices as effective surrogates for *** repeatability of the LidAR biomass indices at discrete events was at least similar to and often higher than AGB,particularly under water *** correlations between calculated CGR for AGB and the LidAR indices were moderate to high and varied between ***,across all experiments,the repeatabilities of the CGR derived from the LidAR indices were appreciably greater than those for AGB,except for the 3dPI in the water-limited *** our experiments,the repeatability of either LidAR index was consistently higher than that of AGB,both at discrete time points and when CGR was *** findings provide promising support for the reliable use of ground-based LidAR,as a surrogate measure of AGB and CGR,for screening germplasm in research and wheat breeding.

关键词： Wheat Biomass LidAR

Post-transcriptional gene silencing, transcriptional gene silencing and human immunodeficiency virus

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World Journal of Virology 2015年第3期4卷 219-244页

作者： Catalina Méndez Chantelle L Ahlenstiel anthony d Kelleher the Kirby Institute for Infection and Immunity Wallace Wurth Building-Level 5Faculty of MedicineUniversity of New South Wales 2nd St Vincent’s Centre for Applied Medical Research

While human immunodeficiency virus 1(HIV-1) infectionis controlled through continuous, life-long use of a combination of drugs targeting different steps of the virus cycle, HIV-1 is never completely eradicated from the body. despite decades of research there is still no effective vaccine to prevent HIV-1 infection. Therefore, the possibility of an RNA interference(RNAi)-based cure has become an increasingly explored approach. Endogenous gene expression is controlled at both, transcriptional and post-transcriptional levels by noncoding RNAs, which act through diverse molecular mechanisms including RNAi. RNAi has the potential to control the turning on/off of specific genes through transcriptional gene silencing(TGS), as well as finetuning their expression through post-transcriptional gene silencing(PTGS). In this review we will describe in detail the canonical RNAi pathways for PTGS and TGS, the relationship of TGS with other silencing mechanisms and will discuss a variety of approaches developed to suppress HIV-1 via manipulation of RNAi. We will briefly compare RNAi strategies against other approaches developed to target the virus, highlighting their potential to overcome the major obstacle to finding a cure, which is the specific targeting of the HIV-1 reservoir within latently infected cells.

关键词： Human immunodeficiency virus 1 RNA interference Reservoirs Epigenetics Latency Transcriptional gene silencing Post-transcriptional gene silencing

An improved culturing method for opiine fruit fly parasitoids and its application to parasitoid monitoring in the field

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Insect Science 2018年第1期25卷 99-108页

作者： Ayad Masry Michael J. Furlong anthony R. Clarke John Paul Cunningham School of Earth Environmental and Biological Sciences School Queensland University of Technology (QUT) Brisbane Queensland Australia School of Biological Sciences the University of Queensland St Lucia Queensland Australia plant Biosecurity Cooperative Research Centre Bruce ACT Australia department of Economic development Jobs Transport and Resources AgriBio Centre La Trobe University Bundoora Victoria Australia

Good culturing methods play an important role in the study of insect behavior and its application to pest management. Here, we describe and validate a new method for rearing the parasitoid wasp, diachasmirnorpha kraussii, which attacks some of the world＇s worst fruit fly pests and is an internationally used biological control agent. Our method differs from standard culturing approaches by presenting adult wasps with host- infested artificial media within a ＂culturing bag,＂ which mimics a natural （fruit） oviposition substrate. In laboratory trials using wild collected d. kraussii, the culturing bag method was compared to the use of host-infested nectarines, and a commonly used laboratory method of presenting host-infested artificial media within Petri dishes. The culturing bag method proved to be a significant improvement on both methods, combining the advantages of high host survival in artificial media with parasitism levels that were the equivalent to those recorded using host-infested fruits. In our field study, culturing bags infested with the Queensland fruit fly, Bactrocera tryoni, and hung in a mixed peach and nectarine orchard proved to be effective ＂artificial fruits＂ attracting wild d. kraussii for oviposition. Significantly more adult wasps were reared from the culturing bags compared to field collected fruits. This was shown to be due to higher fruit fly larval density in the bags, as similar percentage parasitism rates were found between the culturing bags and ripe fruits. We discuss how this cheap, time-efficient method could be applied to collecting and monitoring wild d. kraussii populations in orchards, and assist in maintaining genetic variability in parasitoid laboratory cultures.

关键词： Bactrocera biological control fruit fly mass rearing natural enemies Tephritidae wasp

Afterword to Sperm morphometrics today and tomorrow special issue in Asian Journal of Andrology

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Asian Journal of Andrology 2016年第6期18卷 895-897页

作者： Caries Soler Trevor G Cooper anthony Valverde Jesfis L Yanliz department of Functional Biology and Physical Anthropology University of Valencia 46100 Burjassot Spain department of R+d Proiser R+D Science Park University of Valencia 46980 Paterna Spain Tuen Mun New Territories Hong Kong SAR China department of Animal Production and Food Science Higher Polytechnic School of Huesca University of Zaragoza Ctra Cuarte S/N 22071 Huesca Spain

The problems associated with the subjective assessment of human sperm morphology have been well aired in another Asian Journal of Andrology Special Issue1 that marked the publication of the 5th edition of the WHO Semen analysis manual, and contrary views have subsequently been presented） However, the vagaries of the eye-brain system in assessing whether a sperm head is large or small can be eliminated by objective assessment where definitive structures are defined by their dimensions. These can then be classified automatically into as many categories as the data permit, conventionally on the basis of preset upper and lower limits, but also by more comprehensive analysis as discussed here.

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