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类星体PKS1448—232的吸收线光谱

科学通报 1982年第17期27卷 1057-1061页

作者：陈建生,donald c.morton,Bruce A.Peterson,Alan E.Wright,David L.Jauncey 中国科学院北京天文台英国-澳大利亚天文台澳大利亚国立大学Stromlo and Siding Spring天文台澳大利亚国立射电天文台澳大利亚联邦科工组织无线电物理部

一、引言在系统地进行南天射电源的光学证认工作中,Savage,Bolton和Wright于1977年发现了射电源PKS1448—232和—个具有紫外色超的16（?）4恒星状的天体的位置相符合,并给出它的光学证认图。他们利用英-澳3（?）9反光望远镜对这个天体... 详细信息

一、引言在系统地进行南天射电源的光学证认工作中,Savage,Bolton和Wright于1977年发现了射电源PKS1448—232和—个具有紫外色超的16（?）4恒星状的天体的位置相符合,并给出它的光学证认图。他们利用英-澳3（?）9反光望远镜对这个天体进行了低色散光谱的观测,证实了它是一个发射线红移为Zcm=2.22的类星体,并发现这个类星体的光谱存在有丰富的吸收线,其中大部分的吸收线分布在波长小于Lα的区域。因此,PKS1448-232被列入英-澳望远镜的《类星体吸收线光谱研究》的观测对象之一。该类星体的精确坐标是:

关键词：类星体吸收线望远镜 PKS1448 短波高频(3兆赫-30兆赫) 活动星系类星体发射线

In situ selective laser gas nitriding for composite TiN/Ti-6Al-4V fabrication via laser powder bed fusion

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Journal of Materials Science & Technology 2020年第10期42卷 98-107页

作者： P.A.morton H.c.Taylor L.E.Murr O.G.Delgado c.A.Terrazas R.B.Wicker W.M.Keck center for 3D Innovation The University of Texas at El PasoEl PasoTX79968USA Department of Mechanical Engineering The University of Texas at El PasoTX 79968USA Department of Metallurgical Materials and Biomedical EngineeringThe University of Texas at El PasoTX 79968USA

Laser-assisted gas nitriding of selective Ti-6Al-4V surfaces has been achieved during laser powder bed fusion fabrication by exchanging the argon build gas environment with *** variation of processing parameters allowed microdendritic Ti N surface coatings to be formed having thicknesses ranging from a few tens of microns to several hundred microns,with TiN dendrite microstructure volume fractions ranging from 0.6 to 0.75;and corresponding Vickers microindentation hardness values ranging from^7.5 GPa–9.5 *** TiN hard layers ranging from 50μm to 150μm thick were also fabricated in the laser-beam additively manufactured Ti-6Al-4V alloy producing prototype,hybrid,planar composites having alternating,ductile Ti-6Al-4V layers with a hardness of^4.5 GPa and a stiff,TiN layer with a hardness of^8.5 *** results demonstrate prospects for fabricating novel,additively manufactured components having selective,hard,wear and corrosion resistant coatings along with periodic,planar or complex metal matrix composite regimes exhibiting superior toughness and related mechanical properties.

关键词： Ti-6Al-4V TiN ceramic coatings and embedded layers Dendritic microstructures Selective laser melting Additive manufacturing Metal matrix composites Selective nitriding

An Exome-seq Based Tool for Mapping and Selection of candidate Genes in Maize Deletion Mutants

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Genomics, Proteomics & Bioinformatics 2018年第6期16卷 439-450页

作者： Shangang Jia Kyla morton chi Zhang David Holding Department of Agronomy and Horticulture Center for Plant Science InnovationBeadle Center for BiotechnologyUniversity of Nebraska School of Biological Sciences Center for Plant Science InnovationBeadle Center for BiotechnologyUniversity of Nebraska

Despite the large number of genomic and transcriptomic resources in maize, there is still much to learn about the function of genes in developmental and biochemical processes. Some maize mutants that were generated by gamma-irradiation showed clear segregation for the kernel phenotypes in B73 ? Mo17 F2 ears. To better understand the functional genomics of kernel development,we developed a mapping and gene identi?cation pipeline, bulked segregant exome sequencing(BSEx-seq), to map mutants with kernel phenotypes including opaque endosperm and reduced kernel size. BSEx-seq generates and compares the sequence of the exon fraction from mutant and normal plant F2 DNA pools. The comparison can derive mapping peaks, identify deletions within the mapping peak, and suggest candidate genes within the deleted regions. We then used the public kernel-speci?c expression data to narrow down the list of candidate genes/mutations and identi?ed deletions ranging from several kb to more than 1 Mb. A full deletion allele of the Opaque-2 gene was identi?ed in mutant 531, which occurs within a $200-kb deletion. Opaque mutant 1486 has a 6248-bp deletion in the mapping interval containing two candidate genes encoding RNA-directed DNA methylation 4(RdDM4) and AMP-binding protein, respectively. This study demonstrates the ef?-ciency and cost-effectiveness of BSEx-seq for causal mutation mapping and candidate gene selection,providing a new option in mapping-by-sequencing for maize functional genomics studies.

关键词： Maize functional genomics Mapping-by-sequencing Exome-seq Opaque mutant Bulked segregation analysis

The Sediment and Hydrographic characteristics of Three Horseshoe crab Nursery Beaches in Hong Kong

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Journal of Ocean University of Qingdao 2003年第1期2卷 35-43页

作者： Helen M.c. chiu Brian morton Environmental Resources Management (ERM)-Hong Kong Ltd Swire Institute of Marine Science and Department of Ecology and Biodiversity 979 King's Road Taikoo Place Island East Hong Kong University of Hong

Horseshoe crab juveniles have been recorded from sand and sandy-mud nursery beaches at Pak Nai (western New Territories), San Tau and Shui Hau (Lantau Island), Hong Kong. In order to provide a better understanding of these beaches and to identify those plausible factors which have made them preferred by spawning horseshoe crabs, environmental parameters, including temperature, salinity, pH and dissolved oxygen content of the water, and particle size distribution and organic matter content of the sediments at the three sites, were determined and compared. The hydrographic and sediment data obtained for the three study sites have revealed some common environmental features. The three nursery beaches are relatively remote, and far (in Hong Kong terms) from urbanized and densely populated areas. The beaches are generally well sheltered from strong wave action and inundated regularly by estuarine waters. Horseshoe crab adults tend to select these beaches for spawning as their protected features ensures the laid eggs are less likely to be washed out of the sand, and hatched juveniles can feed on the meiofauna and grow. Sediments of the three beaches largely comprise medium-sized sand particles and are moderately sorted, suggesting medium porosity and good water permeability. Such a sand type, with the generally high oxygen levels in incursing waters, may help create a well-oxygenated micro-environment for the normal development of horseshoe crab eggs, larvae and juveniles. Lantau Island beaches at San Tau and Shui Hau are relatively free from organic pollution, as reflected in generally high dissolved oxygen level, and low BOD 5 and ammonia nitrogen values. Pak Nai is, however, more polluted.

关键词： sediment hydrography horseshoe crab nursery beaches Hong Kong

coastal eutrophication, land use changes and ceratium furca (Dinophyceae) blooms in Pago Pago Harbor, American Samoa 2007-2009

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chinese Journal of Oceanology and Limnology 2011年第4期29卷 790-794页

作者： Steve L. morton Andrew SHULER Jeff PATERNOSTER Sharon FANOLUA Don VARGO NOAA/National Ocean Service Marine Biotoxins Program Charleston SC 29412 USA American Samoa community college Community and Natural Resources Pago Pago American Samoa 96799 USA

The bloom forming dinoflagellate, ceratium furca, has been linked with coastal eutrophication worldwide in tropical and subtropical locations. During the summer of 2007, an unusual 6-month long bloom of c. furca was observed in Pago Pago Harbor, Tutuila Island, American Samoa. Incidents of dinoflagellate blooms in this area have not been previously reported. The bloom was first reported in May and dissipated in November 2007. In February-March 2009, a similar c. furca bloom was observed. During both blooms, no fish mortality events were reported. Maximum cell counts were observed on September 20, 2007 at 9 200 cell/mL. At this time, total nitrogen was measured at 1.2 mg/L while total phosphate was below detection limits. changes in land use practices may have been the primary driver of these blooms. Intense fertilization of athletic fields coupled with ineffective management strategies is hypothesized to have a direct link to the increase in nutrients found in the Pago Pago Harbor and may have been the trigger for the initialization of these blooms. During 2008, the fields were not used due to an infestation of the fire ant, Solenopsis geminata. Once controlled, the fields were opened again in 2009 and fertilizers were applied in January, a month before the bloom was observed.

关键词： eutrophication American Samoa ceratium furca

Morphotaxonomy and seasonal distribution of planktonic and benthic Prorocentrales in Karachi waters,Pakistan Northern Arabian Sea

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chinese Journal of Oceanology and Limnology 2013年第2期31卷 267-281页

作者： Sonia MUNIR Zaib-un-nisa BURHAN Tahira NAZ P.J.A.SIDDIQUI Steve L.morton centre of Excellence in Marine Biology University of Karachi-75270Pakistan National Oceanic and Atmospheric Administrations 219 Fort Johnson RoadCharleston SC29412USA

Morphotaxonomy and seasonal abundance of dinoflagellates of the genera Prorocentrum and Mesoporos （Prorocentrales） were studied from nutrient-rich waters, Karachi Harbor and the mouth of the Manora channel, Pakistan during May 2002-July 2003. Using both light and scanning electron microscopy, 13 species of Prorocentrales were identified according to cell shape, size, ornamentation of thecal plates, and architecture of apical platelets, apical pore area, marginal pores, and intercalary bands. P. sigmoides, P. arcuatum, P. scutellum, P. donghaiense, P. balticum, P. minimum, P. emarginatum, P. lima, P. faustiae, and Mesoporos perforatus constitute new records for sindh coast of Pakistan. The most abundant species were P. minimum/P, balticum （4.5x103 cells/L）, P. micans （1.1~103 cells/L）, P. gracile/P, sigmoides （2.5 x 102 cells/L） and P. donghaiense （6.6 x 103 cells/L） at temperatures of 29-31 ~c and salinities of 35-40. Maximum abundance was observed in winter and lower abundance in summer. There was no significant change in the distribution of species between stations except for the benthic species which occurred close to Karachi Harbor waters. Significant positive correlations were observed between Prorocentrum spp. and temperature （R2=0.27） and negative correlations with salinity （R2=-0.32） except for P. minimum and P. emarginatum which has negative correlation with temperature （R2=-0.24） and positive with salinity （R2=0.08, 0.19）. The finding of potential okadaic-acid producing species of benthic Prorocentrum call for monitoring for possible human health problems in this region.

关键词： ecology morphology planktonic/benthic Prorocentrales harmful algae scanning electronaaicroscopy northern Arabian Sea

Lentiviral Gene Therapy for Artemis-Deficient ScID

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四川生理科学杂志 2022年第12期44卷 2107-2107页

作者： morton J cowan From the Departments of Pediatrics (M.J.c. J.Y. J.F. C.F.-B. U.S. M.K. J.D. J.L.-B. W.C. S.C. R.C. C.C.D. J.M.P.) and Epidemiology and Biostatistics (J.F.H.) the Smith Cardiovascular Research Institute (M.J.C. J.M.P.) and the School of Pharmacy (J.L.-B.) University of California San Francisco (UCSF) and UCSF Benioff Children’s Hospital (M.J.C. J.F. J.D. J.L.-B. J.O. C.C.D. J.M.P.) San Francisco the Department of Pediatrics University of California San Diego and Rady Children’s Hospital San Diego (L.B.) and the Department of Pediatrics UCLA Mattel Children’s Hospital Los Angeles (C.Y.K.) — all in California the Department of Pediatrics Johns Hopkins All Children’s Hospital St. Petersburg FL (D.C.) the Department of Pediatrics Sainte-Justine University Hospital Center University of Montreal Montreal (H.D.) Tuba city Regional Health care Tuba City (C.G. D.H.) and Phoenix Children’s Hospital Phoenix (H.K.M.) — both in Arizona the Department of Pediatrics University of Washington Seattle Children’s Hospital Seattle (A.P.) clinical Development Roche Diagnostics Solutions Singapore (D.P.) the National Institute of Allergy and Infectious Diseases National Institutes of Health Bethesda MD (H.L.M.) and the Department of Genetics Cell Biology and Development University of Minnesota Minneapolis (R.S.M.).

Background:The DNA-repair enzyme Artemis is essential for rearrangement of T-and B-cell *** in DcLRE1c,which encodes Artemis,cause Artemis-deficient severe combined immunodeficiency(ART-ScID),which is poorly responsiv... 详细信息

关键词： ScID immunodeficiency Artemis

Long-Term Fate of Agent Orange and Dioxin TcDD contaminated Soils and Sediments in Vietnam Hotspots

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Open Journal of Soil Science 2019年第1期9卷 1-34页

作者： Kenneth Ray Olson Lois Wright morton Department of NRES College of Agricultural Consumer and Environmental Sciences University of Illinois Urbana IL USA Department of Sociology College of Agriculture and Life Sciences Iowa State University Ames IA USA

The soils, tropical climate, and network of canals and rivers of southern Vietnam have created one of the most diverse tropical jungles and intensely cultivated landscapes of Southeast Asia. This paradise has a long history of numerous wars, foreign occupations, and most recently the Second Indochina War (aka the Vietnam War 1965-1972) which defoliated rain forests and ancient wetland mangroves and left behind contaminated soil and sediment hotspots. During this war, the United States (US) military sprayed 80 million liters of Agent Orange contaminated with the dioxin TcDD in a guerrilla war against communist insurgents. Agent Orange was a synthetic plant growth regulator comprised of equal amounts of two herbicides 2,4-dichloro phenoxyacetic acid c8H6cl2O3 (2,4-D) and 2,4,5-trichlorophenoxyacetic acid c8H5cl3O3 (2,4,5-T). TcDD, the dioxin, 2,3,7,8-tetrachlorodibenzodioxin (c12H4cl4O2) was an unintended byproduct of the accelerated combustion process used in the manufacture of herbicides containing 2,4,5-T. Agent Orange has frequently been blamed for soil and sediment contamination and long-term human health problems;however, the true source of harm is the dioxin TcDD. Agent Orange has a short half-life of days and weeks after application to vegetation, and has not been found to persist, after 50 years, in the water or soils of southern Vietnam. However, the half-life of dioxin TcDD depends on where it is deposited and varies from 1 to 3 years on soil surfaces that have been fully exposed to sunlight, to as long as 20 to 50 years or more when buried in tropical subsoils, and more than 100 years in river and sea sediments. Dioxin TcDD was heavily concentrated in the US Air Force bases in Vietnam where the herbicides were stored, loaded on planes and helicopters for aerial spraying, and used extensively around military base perimeter fences as a security measure to prevent surprise attacks. Bien Hoa Air Force base, 40 km northeast of Ho chi Minh city, continues to be

关键词： Soils of Vietnam Agent Orange Dioxin TcDD Herbicides Soil contaminant Sediment contaminant Half-Life Hotspots Operation Ranch Hand US Airbases in Vietnam Vietnam War cu chi Soil Tunnels Guerilla Warfare Incineration

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高红移类星体吸收线光谱的研究

Research in Astronomy and Astrophysics 1981年第2期 89-96页

作者：陈建生,donald c. morton,Bruce A. Peterson,Allen E. Wright,David L. Jauncey 中国科学院北京天文台英-澳天文台 Stromlo and Siding Spring天文台 cSIRO国立射电台 Parkes cSIRO无线电物理部澳澳澳

作者用英-澳四米望远镜的RGo卡焦摄谱仪及其附属的IPcS系统获得了分辨率为2的四个高红移类星体的光谱,并利用这些光谱讨论了:（Ⅰ）由PKS0805+046和PKS1442+101的Lα/Lβ对及Lα/Lγ对的强相关证实了,大量存在于高红移类星体Lα发射短... 详细信息

作者用英-澳四米望远镜的RGo卡焦摄谱仪及其附属的IPcS系统获得了分辨率为2的四个高红移类星体的光谱,并利用这些光谱讨论了:（Ⅰ）由PKS0805+046和PKS1442+101的Lα/Lβ对及Lα/Lγ对的强相关证实了,大量存在于高红移类星体Lα发射短波区的吸收线是氢云吸收的结果;（Ⅱ）吸收线分布和Lα/Lβ对相关函数的分析反映了PKS0528-250可能是一个例外,需要进一步的观测来证实这种特殊性;（Ⅲ）由类星体抛射出来的物质的吸收,或与类星体成协的星系团或插入星系的吸收都可造成含有金属线的吸收线红移系统;（Ⅳ）由Lα/Lβ对的生长曲线定出的柱密度和弥散速度的随机性,支持了纯Lα的吸收来自大爆炸宇宙早期原始氢云的假说;（Ⅴ）单位红移的氢云密度随红移的分布取决于Z>3的类星体的吸收线资料。

关键词：类星体发射线线光谱氢云金属线活动星系金属压制材料类星体吸收线谱线位移红移