Cerumen types in Choctaw Indians

Certinen from 432 Choctaw Indians from Mississippi was classified as sticky or dry. The frequency of the autosomal recessive dry type was intermediate between that for Indians of western North America and that for Mayan groups of southern Mexico.     

Hemoglobin patterns in American Indians

Two populations of North Carolina have been analyzed for hemoglobin patterns by paper electrophoresis. Of 534 Cherokee Indians, both mixed and full bloods, all showed normal hemoglobin. Lumbee Indians of less certain ethnic status had 1.7 percent of hemoglobin S, an equal amount of hemoglobin C, and one possible hemoglobin D trait among 1332 bloods studied.     

Hemoglobin types of the Caingang Indians of Brazil

We studied the hemoglobin types of 440 individuals (306 unrelated) cytologically and by paper electrophoresis. These included 334 (252 unrelated) putative "full bloods." No abnormal types were found.     

Hemoglobin variant common to Chinese and North American Indians: alpha-2-beta-22 Glu-Ala

An electrophoretically slow hemoglobin variant, in which the structural change involves the replacement of a glutamyl residue by alanyl at position beta-22, was reported in two groups of North American Indians: hemoglobin-G Coushatta, in Alabama-Coushatta Indians in Texas; and hemoglobin-G Saskatoon, in descendants of Santee Indians living in Canada. Hemoglobin-G Hsin-Chu, found in Taiwan in a Chinese from the northern Chinese province of Liaoning, is now shown to have the same structural anomaly.     

Amino acid transport: evidence for genetic control of two types in human kidney

A mutation affecting renal transport of proline, hydroxyproline, and glycerine occurs in man. In the presumed homozygote there is still significant residual transport of these compounds; however, this remaining function is saturated at normal concentrations of substrate in the plasma and is not inhibited by L-proline in the expected way. The presumed heterozygote has partial loss of a transport system common to the three substrates, which becomes saturated at high concentrations of substrate and is inhibited by L-proline. Two different types of transport systems are proposed: a common system and systems with lower capacity and greater specificity. The two types of transport appear to be controlled by separate genes.     

Amino Acid transport: evidence for genetic control of two types in human kidney

In the report "Amino acid transport: evidence for genetic control of two types in human kidney" by C. R. Scriver and O. H. Wilson (17 Mar., p. 1428), the first sentence in the abstract should read "A mutation affecting renal transport of proline, hydroxyproline, and glycine occurs in man."     

Understanding actor-centered adaptation limits in smallholder agriculture in the Central American dry tropics

Adaptations made by agrarian households in the face of global change risks are largely dependent on their livelihood goals. I argue that adaptation-limit research is crucial to many agrarian development programs because a focus on adaptation limits may allow researchers and practitioners to better understand and support successful adaptation and allow smallholders to pursue their goals. In this study of smallholder farming in Northwest Costa Rica, I found that security and the unique parcelero identity of rice farmers in this region define livelihood goals. I show that an understanding of the multidimensionality and fluidity of farmer livelihood goals may enrich our current understanding of actor-centered adaptation limits as insurmountable thresholds. In response to worsening global change risks, farmers in this study traded off certain goals to pursue others. In this way, farmers do not perceive adaptation limits as insurmountable. Alternative indicators of adaptation limits did exist; irreversibility in adaptation and the great hardship associated with tradeoffs among livelihood goals may mark adaptation limits.     

水稻不同籼粳分化类型的光合特性比较与遗传分析

本文比较分析了水稻不同籼粳分化类型材料在抽穗期和成熟期的净光合速率、水分蒸腾速率、气孔导度等反映光合作用特性的性状指标.本研究基于分子聚类结果选出8个育成恢复系,与生产上大面积推广应用的8个水稻不育系,按不完全双列杂交设计(8×8)组配成一套包括亲本和F1代在内的2个世代遗传材料,采用加性—显性遗传模型(AD模型)系统分析了不同类型材料光合特性表现的遗传效应及与产量性状间的遗传相关性.结果表明:(1)不同籼粳分化类型品种的光合生理特性存在差异,籼型品种在齐穗期光合速率较高,成熟期光合作用明显减弱;粳型品种在成熟期仍然保持一定的光合作用,光合功能期较长.(2)不同分化类型的恢复系亲本及所配组合F1产量和主要光合特性的性状指标的表型值存在较大差异,受基因加性和显性效应的影响.(3)主要光合特性的遗传率分析表明,除成熟期的水分利用率不显著外,其余光合特性指标均达到显著或极显著差异水平.     

Antibodies to genetic types of gamma globulin after multiple transfusions

Seventeen of 24 sera from children who had received multiple transfusions contained agglutinating antibodies against a Gm factor absent in the individual's serum gamma globulin. Each of these agglutinators was highly specific for a single Gm factor, and all proved useful as reagents for genetic typing. The accumulated evidence indicates that they resulted from genetically foreign gamma globulin introduced by transfusion.     

粘滞知识的形成与转移

本文讲述了粘滞知识的概念，研究了知识转移中粘滞知识的形成，在此基础上提出了实现粘滞知识有效转移的对策。     

Developments in genetic modification of cattle and implications for regulation,safety and traceability

Genetic modification techniques, in particular novel gene editing technologies, hold the yet unfulfilled promise of altering genetic traits in farm animals more efficiently than by crossbreeding, allowing for a more rapid development of new cattle breeds with distinct traits. Gene editing technologies allow for the directed alteration of specific traits and thereby have the potential to enhance, for instance, disease resilience, production yield and the production of desired substances in milk. The potential implications of these technological advancements, which are often combined with animal cloning methods, are discussed both for animal health and for consumer safety, also with consideration of available methods for the detection and identification of the related products in the food supply chain. Finally, an overview is provided of current regulatory approaches in the European Union (EU) and major countries exporting beef to the EU, for products from animals bred through established practices as well as modern biotechnologies.     

春播糯玉米优质高产栽培技术

以建瓯市郊区生产实践为依据,从选用良种、精细整地、适时播种、合理密植、适龄移栽、病虫害防治及适时采收等方面总结了春播糯玉米的优质高产栽培技术。     

美国Reid种质的遗传改良和利用研究

玉米种质资源是玉米育种的物质基础,任何一个成功的玉米育种家,都非常重视了解、掌握丰富多样的玉米种质资源,并充分认识、重组和利用它们。从20世纪70年代至今,我国杂交玉米主要利用的玉米种质资源有美国Reid、旅大红骨、四平头、Lancaster、P78599、Suwan和Tuxpeno等,其中美国Reid种质在中国玉米育种和生产中的研究与应用广泛,贡献巨大。     

海南岛燥红土发生学特性的薄片观察

燥红土薄片的显微镜观察表明,由于长期受干热的生物气候条件影响,燥红土在发育过程中矿物风化淋溶程度较弱,各种分解形态的有机残体数量少,有机质含量缺乏.燥红土的主导形成过程是红化作用,由于遭受侵蚀,燥红土近代成土过程遭受砂化,表层呈现漂白砂型土壤微垒结.     

栝楼种质资源亲缘关系的RAPD分析

利用RAPD分子标记技术对栝楼种质资源圃中的28个性状有差异的单株进行聚类分析研究,从而了解它们之间的亲缘关系.结果表明,浙江省的吊瓜和安徽省的栝楼之间遗传距离较远;安徽省内栝楼的种质资源较为丰富,资源大体上可以分为5大类;同一类中种质资源在植物学和生物学性状上仍存在有较多的差异性;本研究还发现"大麻籽"和"大麻籽二号"虽然外部形态相似,但它们的遗传距离较远.因此,对栝楼种质资源进行分类时不仅要从外部形态上进行分析,还要利用分子生物学方法作进一步的验证.     

籼型三系杂交水稻单茎叶干物质重的发育遗传研究

采用数量性状的加性－显性发育遗传模型，分析了按NCⅡ交配设计的两套籼型三系交水稻茎叶干物质重的发育遗传规律，结果表明，在不同发育阶段单茎叶干物质重以显性效应为主，控制单茎叶干物质重的加性效应基因是间断表达的，显性效应基因的表达呈连续性，加性效应和显性效应基因在单茎叶干物质重发育的全过程中是有选择地表达的，随着发育进程的推进，单茎叶干物质重杂种优势趋于减弱，不同发育阶段单茎叶干物质重与最终生物产量之间在生育前期加性相关趋于减弱，而显性相关逐渐增强，生育中期加性相关趋于稳定，而显性相关逐渐减弱，生育后期加性和显性相关均保持稳定。     

鲜食糯玉米新品种引进及应用研究初报

引进了11个鲜食糯玉米新品种，组织安排了多点试验，对品种的丰产性、稳产性、抗逆性、适应性、品质及植物学特征进行了研究与鉴定。结果表明，奥玉特1号、闽糯0018两个品种表现丰产性、稳产性好，抗逆性较强，适应性广，品质较好，适宜我省种植。     

Distribution of mating types and genetic diversity induced by sexual recombination in Setosphaeria turcica in northern China

Mature ascocarps and ascospores in the heterothallic ascomycete fungus, Setosphaeria turcica, were successfully produced in Sach’s medium with barley culm as the mating stimulator after four weeks’ coincubation of two opposite mating type isolates at 25°C in darkness. A single isolate could not produce ascospores or ascocarps. The ascocarps were produced on the exposed surface and embedded parts of barley culm or in the upper layer of the medium. The asci linked themselves to ascocarp with their short handles and assembled at the bottom of the ascocarp. Many asci had four to six colorless mature ascospores with one to six septa. But asci with eight ascospores were also found. Using isolate 9914 and isolate 9961 as standard testers for mating types (MAT1 and MAT2), respectively, 94 isolates of S. turcica collected from northern China in 1999, 2003, and 2004 were grouped into three mating types: MAT1 (53 isolates), MAT2 (31 isolates) and MAT12 (10 isolates). The MAT12 isolates, which were first found in China, were compatible with not only MAT1 isolates but also MAT2 isolates. No MAT12 isolates were found in 1999, but 2 MAT12 isolates and 8 MAT12 isolates were found in 2001 and 2003, respectively. The geographic distribution of different mating types was unequal among locations. Generally the frequency of MAT1 was significantly higher than that of MAT2 and MAT12. The unequal distribution of mating types suggested a low frequency of genetic recombination. The pathogenicity of different mating type isolates was tested on the susceptible corn inbred B37 and the results revealed that the disease latency period, disease incidence, lesion area and conidia production were not significantly different among the three mating type groups. However, the pathogenicity of the progeny isolates of isolate 99-12 (MAT2, race 1) and isolate 99-15 (MAT1, race 0) was significantly different from the parent isolates, isolate 99-12 and isolate 99-15, suggesting that sexual recombination could cause significantly virulence variation in S. turcica. Random amplification of polymorphic DNA (RAPD) analysis also revealed high genotype diversity among the progeny isolates, indicating that the sexual recombination could also produce significant genetic variation in the fungal pathogen.     

美国新农场安全网的主要内容和影响分析

美国联邦政府将管理农场生产经营风险的一系列支持计划统称为农场安全网,具体包括主要针对农业生产经营中市场风险的农产品计划、主要针对农业生产经营中自然风险的农作物保险计划以及对上述两个计划未覆盖风险进行补充的农业灾害援助计划。2014年美国农业法案对其农场安全网的内容和结构进行调整,试图构建一个各支持计划间有机组合、注重补贴效率和强化风险管理的新农场安全网。新农场安全网下的综合支持量虽然不会超过美国在WTO的减让承诺,但增加美国农产品贸易争端的潜在范围,降低美国在WTO新协议中削减"黄箱政策"补贴的意愿,对世界农产品贸易产生重要影响。新农场安全网一方面将加剧我国农产品进口压力,另一方面对我国农业补贴政策改革有如下启示:继续加大支持保护力度;坚持市场化改革方向;健全农业保险制度。     

Plastic and moldable metals by self-assembly of sticky nanoparticle aggregates

Deformable, spherical aggregates of metal nanoparticles connected by long-chain dithiol ligands self-assemble into nanostructured materials of macroscopic dimensions. These materials are plastic and moldable against arbitrarily shaped masters and can be thermally hardened into polycrystalline metal structures of controllable porosity. In addition, in both plastic and hardened states, the assemblies are electrically conductive and exhibit Ohmic characteristics down to approximately 20 volts per meter. The self-assembly method leading to such materials is applicable both to pure metals and to bimetallic structures of various elemental compositions.