检索结果-南通市图书馆

Stable isotope paleohydrology and chemostratigraphy of the Albian Wayan Formation from the wedge-top depozone,North American Western Interior Basin

引用

Science China Earth Sciences 2017年第1期60卷 44-57页

作者： Jeffrey B.ROSS Greg A.LUDVIGSON Andreas MOLLER Luis A.GONZALEZ J.D.WALKER Department of Geology University of Kansas kansas Geological Survey University of Kansas

Understanding of the role of atmospheric moisture and heat transport in the climate system of the Cretaceous greenhouse world represents a major challenge in Earth system science. Stable isotopic paleohydrologic data from mid-Cretaceous paleosols in North America, from paleoequatorial to paleoArctic latitudes, have been used to constrain the oxygen isotope mass balance of the Albian hydrologic cycle. Over the range from 40°-50°N paleolatitude, sideritic paleosols predominate, indicating paleoenvironments with positive precipitation-evaporation （P-E） balances. Local exceptions occur on leeward side of the Sevier Orogen, where calcic paleosols in the wedge-top depozone record paleoenvironments with negative P-E balances in the orographic rain shadow. Stratigraphic sections in the Wayan Formation of Idaho （WF） were sampled from the wedge-top depozone. The units consist of stacked m-scale mudstone paleosols separated by m-scale sandstone-siltstone beds. Sections were sampled for organic carbon isotope profiles, and B-horizons from 6 well-developed paleosols were sampled for detrital zircons to determine maximum depositional ages. The first of these from the WF has produced a U-Pb concordia age of 101.0±1.1 Ma. This same WF section has produced a stratigraphic trend of upwardly decreasing δ18C values ranging from -24‰ upwards to -27‰ VPDB, suggesting correlation to the late Albian C15 C-isotope segment. Pedogenic carbonates from the WF principally consist of micritic calcite, with carbon-oxygen isotope values that array along meteoric calcite lines （MCLs） with δ18O values that range from -9.47‰ up to -8.39‰ VPDB. At approximately 42°N paleolatitude, these MCL values produce calculated paleoprecipitation values of-8.12‰ to -7.04‰ VSMOW, a range that is consistent with the estimates produced from other proxies at the same paleolatitudes across North America. These results indicate that despite the orographic rain shadow effect, the processes of meridional atmospheric moist

关键词： Cretaceous Paleoclimate Wayan Formation Pedogenic carbonates Geochronology

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Grasshoppers （Orthoptera： Acrididae） select vegetation patches in local-scale responses to foliar nitrogen but not phosphorus in native grassland

引用

Insect Science 2011年第5期18卷 533-540页

作者： Viviana Loaiza Jayne L. Jonas Anthony Joern Division of Biology Kansas State University Manhattan Kansas USA

Key elements such as nitrogen （N） and phosphorus （P） are often limiting relative to the nutritional needs of herbivores that feed on them. While N often limits insect herbivores in natural terrestrial ecosystems, the effect of P is poorly studied in the field, even though compelling hypotheses from the ecological stoichiometry literature predict its importance. We evaluated small-scale spatial distributions of, and herbivory by, grasshoppers among neighboring plots that vary in foliar-N and -P in tallgrass prairie. Grasshopper densities were 67% greater in N-fertilized plots but detected no effect to grasshopper densities from P-fertilizer. Leaf damage to the dominant grass Andropogon gerardii was 32% greater in N-fertilized plots, but no response to foliar-P was detected. Herbivore damage to a common forb, goldenrod （Solidago missouriensis）, was not strongly linked by fertilizer treatments, although there was increased leaf damage in N-fertilizer treatments when no P was applied （a significant N ~ P interaction）. Under field conditions at local scales, we conclude that spatially heterogeneous distributions of grasshoppers are primarily affected by foliar-N in host plants with little evidence that P-levels contribute to the spatial patterns.

关键词： Andropogon gerardii ecological stoichiometry insect herbivory Konza Prairie N-P fertilization experiment Solidago rnissouriensis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Land 3D-Seismic Data: Preprocessing Quality Control Utilizing Survey Design Specifications, Noise Properties, Normal Moveout, First Breaks, and Offset

引用

Journal of China University of Geosciences 2009年第3期20卷 640-648页

作者： Abdelmoneam Raef Geology Department Kansas State UniversityManhattan Kansas USA Formerly Kansas Geological Survey The University of KansasLawrence USA

The recent proliferation of the 3D reflection seismic method into the near-surface area of geophysical applications, especially in response to the emergence of the need to comprehensively characterize and monitor near-surface carbon dioxide sequestration in shallow saline aquifers around the world, justifies the emphasis on cost-effective and robust quality control and assurance （QC/QA） workflow of 3D seismic data preprocessing that is suitable for near-surface applications. The main purpose of our seismic data preprocessing QC is to enable the use of appropriate header information, data that are free of noise-dominated traces, and/or flawed vertical stacking in subsequent processing steps. In this article, I provide an account of utilizing survey design specifications, noise properties, first breaks, and normal moveout for rapid and thorough graphical QC/QA diagnostics, which are easy to apply and efficient in the diagnosis of inconsistencies. A correlated vibroseis time-lapse 3D-seismic data set from a CO2-flood monitoring survey is used for demonstrating QC diagnostics. An important by-product of the QC workflow is establishing the number of layers for a refraction statics model in a data-driven graphical manner that capitalizes on the spatial coverage of the 3D seismic data.

关键词： preprocessing quality control 3D seismic 4D seismic trace header geometry vertical stacking.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Plant population and weeds influence stalk insects, soil moisture, and yield in rainfed sunflowers

引用

Insect Science 2007年第5期14卷 425-435页

作者： JAWWAD A. QURESHI PHILLIP W. STAHLMAN J. P. MICHAUD Department of Entomology Kansas State University Agricultural Research Center Hays Kansas USA Department of Agronomy Kansas State University Agricultural Research Center Hays Kansas USA

Insect infestation, soil moisture, and yield were examined in populations of≈33 140 plants/ha （low） and ≈ 40 340 plants/ha （high） of an oilseed sunflower, Helianthus annuus L, cv. ＇ Triumph 660CL＇ with two levels of weediness. Less weedy plots resulted from the application of herbicide combination of S-metolachlor and sulfentrazone, whereas more weedy plots resulted from application of sulfentrazone alone. Among the 12 weed species recorded, neither plant numbers nor biomass differed between crop plant densities. Larvae of the stalk-boring insects Cylindrocopturus adspersus （Coleoptera： Curculionidae） and Mordellistena sp. （Coleoptera： Mordellidae） were less abundant in high density sunflowers, ostensibly due to reduced plant size. However, the same effect was not observed for Dectes texanus （Coleoptera： Cerambycidae） or Pelochrista womanana （Lepidoptera： Tortricidae）, two other stalk-boring insects. Soil moisture was highest in low density and lowest in the high density sunflowers that were less weedy. Stalk circumference, head diameter, and seed weight were reduced for sunflower plants with short interplant distances （mean = 20 cm apart） compared to plants with long interplant distances （mean = 46 cm apart）. These three variables were greater in less weedy plots compared with more weedy plot〉 and positively correlated with interplant distance. Yields on a per-hectare basis paralleled those on a per-plant basis but were not different among treatments. The agronomic implications of planting density are discussed in the context of weed and insect management.

关键词： Cylindrocopturus adspersus Dectes texanus Mordellistena sp. neutron probe Pelochrista womanana plant population soil moisture sunflower yield weed control

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Indirect plant defense against insect herbivores： a review

引用

Insect Science 2018年第1期25卷 2-23页

作者： Zainab Aljbory Ming-Shun Chen Department of Entomology Kansas State University Manhattan Kansas USA Hard Winter Wheat Genetics Research Unit USDA-ARS Kansas State University Manhattan Kansas USA

Plants respond to herbivore attack by launching 2 types of defenses： direct defense and indirect defense. Direct defense includes all plant traits that increase the resistance of host plants to insect herbivores by affecting the physiology and/or be- havior of the attackers. Indirect defense includes all traits that by themselves do not have significant direct impact on the attacking herbivores, but can attract natural en- emies of the herbivores and thus reduce plant loss. When plants recognize herbivore- associated elicitors, they produce and release a blend of volatiles that can attract preda- tors, parasites, and other natural enemies. Known herbivore-associated elicitors include fatty acid-amino acid conjugates, sulfur-containing fatty acids, fragments of cell walls, peptides, esters, and enzymes. Identified plant volatiles include terpenes, nitrogenous compounds, and indoles. In addition, constitive traits including extrafloral nectars, food bodies, and domatia can be further induced to higher levels and attract natural enemies as well as provide food and shelter to carnivores. A better understanding of indirect plant defense at global and componential levels via advanced high throughput technolo- gies may lead to utilization of indirect defense in suppression of herbivore damage to plants.

关键词： elicitor indirect plant defense natural enemies volatile

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Apolipoprotein E and Alzheimer’s disease

引用

Acta Pharmaceutica Sinica B 2022年第2期12卷 496-510页

作者： Benjamin R.Troutwine Laylan Hamid Colton R.Lysaker Taylor A.Strope Heather M.Wilkins Department of Neurology University of kansas Medical Center Kansas CityKS 66160USA University of kansas Alzheimer’s Disease Center Kansas CityKS 66160USA Department of Biochemistry and Molecular Biology University of Kansas Medical CenterKansas CityKS 66160USA

Genetic variation in apolipoprotein E(APOE)influences Alzheimer’s disease(AD)***ε4 alleles are the strongest genetic risk factor for late onset sporadic *** AD risk is dose dependent,as those carrying one APOEε4 allele have a 2-3-fold increased risk,while those carrying twoε4 alleles have a 10-15-fold increased *** carrying APOEε2 alleles have lower AD risk and those carrying APOEε3 alleles have neutral *** is a lipoprotein which functions in lipid transport,metabolism,and inflammatory *** specific effects of APOE within the brain include alterations to Aβ,tau,neuroinflammation,and *** we review the association of APOE with AD,the APOE isoform specific effects within brain and periphery,and potential therapeutics.

关键词： Apolipoprotein E Alzheimer’s disease Mitochondria Neuroinflammation Amyloid beta Tau

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Relative toxicity of three wheat herbicides to two species of Coccinellidae

引用

Insect Science 2010年第5期17卷 434-438页

作者： J. P. Michaud German Vargas Department of Entomology Kansas State University Hays Kansas USA

On the High Plains of the USA, herbicides specific for broad-leaf weeds are regularly applied to winter wheat in the early spring, sometimes late enough to coincide with the colonization of fields by cereal aphids and their natural enemies. We tested the toxicity of three such herbicides, Ally （Dupont）, Rave （Syngenta） and 2,4-D ester （generic）, to neonate larvae of two coccinellid species important in cereal aphid biocontrol, Coleomegilla maculata DeGeer and Hippodamia convergens Gurrin-Mrneville. Topical treatment of larvae with 2,4-D resulted in 25% and 60% mortality in the two species, respectively, with surviving C. maculata larvae experiencing a 5% increase in developmental time. No significant effects were noted for the other two materials, save for a 2.5% increase in developmental time for C. maculata larvae exposed to Rave. No material caused significant mortality in either species when larvae were fed on prey （Schizaphis graminum Rondani） treated with herbicide 24 h earlier, although 2,4-D reduced developmental time slightly in C. maculata. When herbicide applications are delayed enough in spring to coincide with aphid activity in wheat, farmers can reduce the risk of disrupting biological control by selecting an alternative to 2,4-D.

关键词： 2,4-D Coleomegilla maculata dicamba Hippodamia convergens Schizaphis graminum thifensulfuron methyl

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Spontaneous Ca2+ oscillations in subcellular compartments of vascular smooth muscle cells rely on different Ca2+ pools

引用

Cell Research 2004年第5期14卷 379-388页

作者： Olesya D. FEDORYAK,Yvonne SEARLS,Irina V. SMIRNOVA,Douglas M. BURNS,Lisa STEHNO-BITTEL Departments of Physical Therapy and Rehabilitation Sciences University of kansas Medical Center kansas City KS 66160 USA Departments of Physical Therapy and Rehabilitation Sciences University of kansas Medical Center kansas City KS 66160 USA Department of Anatomy and Cell Biology University of kansas Medical Center kansas City KS 66160 USA Departments of Physical Therapy and Rehabilitation Sciences University of kansas Medical Center kansas City KS 66160 USA VA Medical Center kansas City MO 64128 USA Departments of Physical Therapy and Rehabilitation Sciences University of kansas Medical Center kansas City KS 66160 USA Department of Anatomy and Cell Biology University of kansas Medical Center kansas City KS 66160 USA

Spontaneous Ca2+ oscillations in vascular smooth muscle cells have been modeled using a single Ca2+ pool. This report describes spontaneous Ca2+ oscillations dependent on two separate Ca2+ sources for the nuclear versus cytoplas- mic compartments. Changes in free intracellular Ca2+ were monitored with ratiometric Ca2+- fluorophores using confo- cal microscopy. On average, spontaneous oscillations developed in 79% of rat aortic smooth muscle cells that were synchronous between the cytoplasm and nucleus. Reduction of extracellular Ca2+ (< 1 μM) decreased the frequency and amplitude of the cytoplasmic oscillations with 48% of the oscillations asynchronous between the nuclear and cytoplasmic compartments. Similar results were obtained with the Ca2+ channel blockers, nimodipine and diltiazem. Arg-vasopressin (AVP) induced a rapid release of intracellular Ca2+ stores that was greater in the nuclear compartment (4.20 ± 0.23 ratio units, n = 56) than cytoplasm (2.54 ± 0.28) in cells that had spontaneously developed prior oscillations. Conversely, cells in the same conditions lacking oscillations had a greater AVP-induced Ca2+ transient in the cytoplasm (4.99 ± 0.66, n = 17) than in the nucleus (2.67 ± 0.29). Pre-treatment with Ca2+ channel blockers depressed the AVP responses in both compartments with the cytoplasmic Ca2+ most diminished. Depletion of internal Ca2+ stores prior to AVP exposure blunted the nuclear response, mimicking the response of cells that lacked prior oscillations. Spontaneous oscillating cells had a greater sarcoplasmic reticulum network than cells that did not oscillate. We propose that sponta- neous nuclear oscillations rely on perinuclear sarcoplasmic reticulum stores, while the cytoplasmic oscillations rely on Ca2+ influx.

关键词： oscillations vascular smooth muscle cells nuclear Ca2+ vasopressin thapsigargin diltiazem nimodipine.

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Phylogenetic and sequence analyses of insect transferrins suggest that only transferrin 1 has a role in iron homeostasis

引用

Insect Science 2021年第2期28卷 495-508页

作者： Diana G.Najera Neal T.Dittmer Jacob J.Weber Michael R.Kanost Maureen J.Gorman Department of Biochemistry and Molecular Biophysics Kansas State UniversityManhattanKansasUSA

Iron is essential to life,but surprisingly little is known about how iron is managed in nonvertebrate *** mammals,the well-characterized transferrins bind iron and are involved in iron transport or immunity,whereas other members of the transferrin family do not have a role in iron *** insects,the functions of transferrins are still poorly *** goals of this project were to identify the transferrin genes in a diverse set of insect species,resolve the evolutionary relationships among these genes,and predict which of the transferrins are likely to have a role in iron *** phylogenetic analysis of transferrins from 16 orders of insects and two orders of noninsect hexapods demonstrated that there are four orthologous groups of insect *** analysis suggests that transferrin 2 arose prior to the origin of insects,and transferrins/,i,and 4 arose early in insect *** sequence analysis of each of the insect transferrins was used to predict signal peptides,carboxyl-terminal transmembrane regions,GPI-anchors,and iron *** on this analysis,we suggest that transferrins 2,and 4 are unlikely to play a major role in iron *** contrast,the transferrin 1 orthologs are predicted to be secreted,soluble,iron-binding *** conclude that transferrin 1 orthologs are the most likely to play an important role in iron ***,it appears that the louse,aphid,and thrips lineages have lost the transferrin 1 gene and,thus,have evolved to manage iron without transferrins.

关键词： hemolymph insect iron homeostasis melanotransferrin phylogeny transferrin

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Genomic insights into hybridization in a localized region of sympatry between pewee sister species(Contopus sordidulus × C. virens) and their chromosomal patterns of differentiation

引用

Chinese Birds 2016年第1期7卷 48-55页

作者： Joseph D.Manthey Mark B.Robbins Biodiversity Institute University of Kansas Department of Ecology and Evolutionary Biology University of Kansas

Background: The Great Plains of the United States includes a large number of hybrid and contact zones between bird species. The amount of gene flow between sister species in these zones ranges from very rare hybridization events to widespread and prevalent introgression. Some of these avian systems have been studied extensively, while others have been indeterminate of whether hybridization exists in areas of sympatry. Using genomic-level approaches allows investigation of genomic patterns of hybridization and gene flow between species—or lack ***: We investigated a narrow zone of sympatry in Nebraska, USA between pewee species(Contopus sordidulus and C. virens), for which no hybridization has been confirmed. We used thousands of single nucleotide polymorphisms to identify potential hybridization and investigate genomic patterns of differentiation between these two ***: We found evidence of multiple hybrid individuals in the contact zone. Little genomic variation was fixed between species, but a large proportion had differentiated allele frequencies between species. There was a positive relationship between genetic differentiation and chromosome ***: We provided the first conclusive evidence of hybridization between C. sordidulus and C. virens, in a region where secondary contact likely occurred due to human disturbance and habitat modification. The genomic patterns of differentiation affirm that these species split in the relatively recent past. Finally, the relationship of chromosome size and genetic differentiation may have resulted from differential rates of chromosomal recombination in songbirds and genetic differentiation between species largely due to genetic drift(possibly in concert with selection).

关键词： Contact zone Hybrid zone Hybridization Chromosomal patterns Next-generation sequencing Contopus North America

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：