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东北地区和黄淮海地区玉米种质利用模式的比较

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玉米科学 2010年第5期18卷 23-28,34页

作者：肖木辑李明顺李新海 Maria luz GEORGE 张世煌中国农业科学院作物科学研究所亚洲玉米生物技术协作网中国实验室北京100081 沈阳农业大学沈阳110161 CIMMYT-Asian Maize Biotechnology Network c/o IRRIDAPO Box7777Metro ManilaPhilippines

利用SSR标记分别对东北春播和黄淮海夏播玉米产区主要自交系的遗传多样性进行分析,并在此基础上对东北和黄淮海地区的玉米种质利用模式进行比较。东北地区利用的种质类型比较丰富,包括PA、PB、旅大红骨、Lan.和塘四平头亚群,利用的杂种... 详细信息

利用SSR标记分别对东北春播和黄淮海夏播玉米产区主要自交系的遗传多样性进行分析,并在此基础上对东北和黄淮海地区的玉米种质利用模式进行比较。东北地区利用的种质类型比较丰富,包括PA、PB、旅大红骨、Lan.和塘四平头亚群,利用的杂种优势模式以PA×旅大红骨为主,在生育期较短的玉米产区Lan.×塘四平头是很重要的利用模式,在黑龙江省和吉林省北部地方种质发挥了重要作用。黄淮海夏播玉米产区利用的种质主要是PA、PB和塘四平头亚群,利用的杂种优势模式以PA×塘四平头为主。PA×PB杂种优势模式呈现上升趋势,有利于实现跨区域整合玉米种质的杂种优势群和模式。

关键词：玉米 SSR 种质资源杂种优势模式

Heavy Metals in Native Potato and Health Risk Assessment in Highland Andean Zones of Junín, Peru

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Journal of Environmental Protection 2020年第11期11卷 921-937页

作者： Edith Orellana María Carolina Bastos Walter Cuadrado Rosa Zárate Vicky Sarapura luz Yallico Fiorella Tabra Diana Bao Universidad Nacional del Centro del Perú Huancayo Perú Centro Internacional de la Papa (CIP) Huancayo Perú

Heavy metals are transferred from the abiotic environment to living organisms, accumulate in food, contaminate the food chain, and are an important route of human exposure involving a potential health risk. In this study, the concentrations of heavy metals (Cd, Fe, Pb, Zn and As) in agricultural soils and tubers of Solanum tuberosum spp. andigena (native potato) were evaluated. Also, an assessment of the health risk associated with the daily intake by the local population was performed in the four districts of the department of Junín, between altitudes of 3800 m to 4200 m. The heavy metals concentrations in soils with native potato cultivation followed the following decreasing order of Fe > Zn > Pb > As > Cd, with values below national standards. The heavy metals content in native potatoes was below the limits recommended by international standards with the exception of Pb. The bioconcentration factor (BCF) for the two native potato varieties in decreasing order was Zn > Cd > Pb > As > Fe, all less than 0.5. The estimated daily intake of metals (EDIM) in adults and children through the consumption of native potatoes was higher for Fe and Zn. The threshold carcinogenic risk values (TCR) for As exceeded the safety limits 1 × 10-4. It is concluded that the residents in the four high Andean localities would be exposed to carcinogenic adverse health effects associated with the intake of native potatoes. It is important to monitor the concentration of As and other heavy metals in the Andean soils and crops in order to implement a soil and crop management program to ensure food quality.

关键词： Bioconcentration Factor Daily Intake Non-Carcinogenic Risk Carcinogenic Risk Native Potato

Changing Concentrations of Heavy Metals in Stream Water as a Result of Slurry Application to Soil

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Journal of Agricultural Science and Technology(A) 2012年第4期2卷 473-480页

作者： M. Mercedes Taboada-Castro M. luz. Rodriguez-Blanco Antonio Dieguez M. Teresa Taboada-Castro Faculty of Sciences University of A Coruna A Zapateira A Coruna 15008 Spain

Several studies focused on nutrients have shown that land use and management practices have a strong influence on stream chemistry. Much less is known about the relationship between heavy metal concentrations in stream water and land use. We compared the variability of trace element concentrations in the stream of a catchment exposed to different types of management practices and land use. This is a small catchment with previous agricultural diffuse and accidental pollution mainly due to the spreading of slurry. The agricultural land was reforested in July 1998. The concentrations of Fe, Mn, Cu and Zn in dissolved phase from surface water samples collected at the catchment outlet were determined over a period of approximately six years. The results suggest that dissolved metal concentrations, especially Cu and Mn, are controlled by the land use and management practices. The median concentrations of studied metals were the highest in the agricultural period. It was also during this period when they all presented the highest concentration peaks, coinciding with a time of heavy application of manure to the soil. Dissolved Fe and Mn showed high dependence of flow rate, whereas Cu and Zn concentrations seemed to be independent of flow.

关键词： Heavy metals agricultural pollution slurry stream water

Central nervous system vasculitis and polyneuropathy as first manifestations of hepatitis C

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World Journal of Gastroenterology 2012年第2期18卷 188-191页

作者： Roberto J Carvalho-Filho Janaína luz Narciso-Schiavon Luciano HL Tolentino Leonardo L Schiavon Maria Lucia G Ferraz Antonio Eduardo B Silva Division of Gastroenterology Hepatitis SectionFederal University of Sao Paulo04037-003 Sao PauloBrazil

Sensory or motor peripheral neuropathy may be observed in a significant proportion of hepatitis C virus (HCV)-infected ***,central nervous system (CNS) involvement is uncommon,especially in cryoglobulin-negative *** describe a case of peripheral neuropathy combined with an ischemic CNS event as primary manifestations of chronic HCV infection without *** improvement was observed after antiviral *** discuss the spectrum of neurological manifestations of HCV infection and review the literature.

关键词： Hepatitis C Central nervous system Poly-neuropathy Interferon-α

Occurrence and Distribution of the Genus Jania J. V. Lamouroux (Corallinales, Rhodophyta) in the Pacific Coast of Baja California and Gulf of California, Mexico

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American Journal of Plant Sciences 2013年第12期4卷 1-13页

作者： luz Elena Mateo-Cid A. Catalina Mendoza-González Luis E. Aguilar-Rosas Raúl Aguilar-Rosas Facultad de Ciencias Marinas Universidad Autónoma de Baja California Ensenada Baja California México Instituto de Investigaciones Oceanológicas Universidad Autónoma de Baja California Ensenada Baja California México Instituto Politécnico Nacional Escuela Nacional de Ciencias Biológicas Departamento de Botánica Ciudad de México México

This paper provides a description of the articulated species of the Tribe Janieae (Corallinales, Rhodophyta) in the Pacific coast of Baja California and Gulf of California, Mexico. This taxonomic report is based on newly collected data in the study area and material currently housed at several herbaria. As a result of the present study, the record of the tribe Janieae is represented at the Pacific coast of Mexico for one genus: Jania J. V. Lamouroux with nine species. Morphological, reproductive and anatomical descriptions are provided in detail. In addition, keys for determination are included, as well as habitat, nomenclature, comparisons with other species and information on distribution. Instead of eleven species of Jania currently recorded for the study area, we recognize only nine. Jania verrucosa is restricted to the occidental coast from the Peninsula of Baja California. The remainder of the species commonly occurs in the Gulf of California and the Pacific coast of Baja California’s Peninsula. On the other hand, the gametangial thalli of J. adhaerens and tetrasporangial conceptacle in J. longiarthra are reported for the first time in Mexico.

关键词： Janieae Morphology Distribution Pacific Mexico

Extraction and Characterization of Starch Fractions of Five Phenotypes <i>Pachyrhizus tuberosus</i>(Lam.) Spreng

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Food and Nutrition Sciences 2014年第19期5卷 1875-1885页

作者： José Luis Ramírez Ascheri luz Haydee Bravo Zamudio Carlos Wanderlei Piler Carvalho Arturo Melendez Arevalo Lais Martins Fontoura Rheology Laboratory Embrapa Food Technology Avenida das Américas Rio de Janeiro Brazil Agronomy and Veterinary Medicine Faculty Brazilian University Campus Universitário Darcy Ribeiro Brasilia Brazil Graduate Program in Food Science and Technology Federal Rural University of Rio de Janeiro Seropédica Brazil

Pachyrhizus tuberosus is a native plant of short life cycle found in South America riverside, which provides easy starch extraction from its tuberous roots. The aim of this study was to determine the physicochemical, rheological and functionality of the starch granules extracted from the roots of five phenotypes identified as V2, V3, V4, V6 and V7. Protein and ash content of all phenotypes were considerable high when compared to other root sources such as cassava varying from 4.35% to 7.43% and 1.58% to 2.49%, respectively, whereas lipid content was lower, between 0.29 and 0.49%. The starch granules were mostly circular and polygonal with varied sizes. The starch granules structural conformation showed cristallinity A type, normally for cereals. The maximum pasting viscosity at 95℃ ranged from 1644 cP (V7) to 2232 cP (V2). The initial temperature of pasting formation occurred at 69.4℃ for V2, 71.5℃ for V3, 87.9℃ for V4, 69.5℃ for V6 and 71.5℃ for V7. These values showed high variability within the phenotypes and generally high for roots and tubers starches. The maximum viscosity at 95℃ for V2, V3, V4, V6 and V7 were 2232, 2150, 1995, 2214 and 1644 cP, respectively. The viscosity curves showed low tendency to retrogradation. The thermal properties showed that the enthalpy of gelatinization varied from 8.91 J/g (V3) to 11.78 J/g (V2). The initial gelatinization temperature varied from 63.19℃ (V6) to 65.14℃ (V4). The swelling power at 90℃ ranged from 14.7% to 20.1% p/p and solubility from 10.3% (V2) to 27.2% (V7). It is concluded that Pachyrhizus tuberosus starch showed low retrogradation (1320 - 1560 cP) comparable to non-common native waxy starches, a feature which indicates the capability of using this natural and easy extraction starch source as gelling agent in certain manufactured food of undesirable retrogradation.

关键词： Pachyrhizus tuberosus Physicochemical Rheological Starch Properties

Osmoregulators in Hymenaea courbaril and Hymenaea stigonocarpa under water stress and rehydration

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Journal of Forestry Research 2018年第6期29卷 1475-1479页

作者： Luma Castro de Souza Luana Moraes da luz Je′ssica Taynara da Silva Martins Candido Ferreira de Oliveira Neto Juscelino Goncalves Palheta Tamires Borges de Oliveira Ediane Conceicao Alves Risely Ferraz de Almeida Raimundo Leonardo Lima de Oliveira Roberto Cezar Lobo da Costa Nariane Quaresma Vilhena Universidade estadual paulista ju′lio de mesquita filho JaboticabalSP 14884-900Brazil Universidade Federal Rural da Amazonia(UFRA) Campus CapanemaCapanema 68700-030Brazil Universidade Federal Rural da Amazonia Campus BelemBelem 66077-830Brazil Universidade Federal de Vicosa(UFV) Vicosa 36570-900Brazil Universidade Estadual Paulista Ju′lio de Mesquita Fiho(UNESP) Jaboticabal 14884-900Brazil Universidade do Estado do Para′(UEPA) Bele′m 66113-200Brazil

The objective of this work was to evaluate the effect of different water deficiency and rehydration levels on the concentrations of osmoregulators in two plant species（Hymenaea courbaril and H. Stigonocarpa） in the Amazon. We adopted a 2×5×5 factorial system,referring to 2 species（H. courbaril and H. stigonocarpa）and 5 stages of hydration and rehydration. The five hydration and rehydration stages were established in:（1）Control treatment E0;（2） Plants with 13 days of stress after incubation—E13;（3） Plants with 26 days of stress E26;（4）The plants that were established after 26 days after incubation and rehydrated for two days（RD2）;（5） rehydrated for two days（RD4）. The plants that were established after 26 days after incubation and rehydrated for four days. The experiment totaled fifty young plants with five *** measurements were performed at the beginning of the experiment（E0） at 13（E13） and 26（E26） days after the water stress, in which the plants were rehydrated,repeating the analyses after two（RD2） and four（RD4）days. Both species increased the sucrose concentration by18%, with a decrease of 52% in starch content. The RD4 time presented the highest mean starch concentration(0.19 mmol g-1 of the residue for H. courbaril and0.27 mmol g;of residue for H. stigonocarpa). Increased proline concentrations were recorded for controls until RD2 for both species. For glycine betaine, the highest increases in treatments E26 and RD2 were observed for the H. courbaril species. Our rehydration period was not sufficient for total recovery of pre-stress concentrations of all studied solutes.

关键词： Amazonia Water stress Osmotic adjustment Proline Sucrose

Finite One-Dimensional Photonic Crystal with Gaussian Modulation: Transmission and Escape

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Optics and Photonics Journal 2017年第10期7卷 170-180页

作者： María de la luz Silba-Vélez David-Armando Contreras-Solorio Rolando Pérez-álvarez Carlos Iván Cabrera Academic Unit of Physics Autonomous University of Zacatecas Zacatecas Mexico Center of Science Research Institute of Basic and Applied Sciences Autonomous University of the State of Morelos Cuernavaca Mexico

This paper studied the transmission coefficient and escape frequencies in a system of planar dielectric layers where the refractive index changes from one layer to another through a Gaussian function. The wave equation with normal incidence is analyzed. For the calculations, the transfer matrix formalism is used. In a previous work, the transmission and escape problem for Gaussian electronic superlattices is investigated. Now it studied the electromagnetic modes for a system formed by layers where the refractive index of the structure is modulated by a Gaussian function. The system presents transparency bands of transmission and gaps without transmission. The escape frequencies are situated near these transparency bands but they do not coincide with them. is the frequency (mode) and Γdescribes the width of the states. For these systems, the escape states are very wide. A non Gaussian system presents resonance peaks in the transmission and the escape states are narrow. The formation of transparency bands in the transmission for a Gaussian system is attributed to the widening of the escape states.

关键词： Transmission Coefficient Escape Frequencies Photonic Crystal

Mycelial Growth of Pleurotus Spp in Se-Enriched Culture Media

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Advances in Microbiology 2013年第8期3卷 11-18页

作者： Marliane de Cássia Soares da Silva Mateus Dias Nunes Jose Maria Rodrigues da luz Maria Catarina Megumi Kasuya Departamento de Microbiologia Federal University of VicosaCampus UFVVicosaBrazil

Selenium (Se) is an essential element to human. However, this element can be in low content in soil of some regions. Se deficiency may cause Keshan disease, thyroid dysfunction and osteoarthritis. The Se-enriched cereals are an interesting way to prevent these diseases. But, recent studies have shown that Se-enriched mushrooms are a better Se source. This occurs due to the high capacity of the fungi to absorb and transform the inorganic Se to organic forms, which are more bioavailable. Pleurotus ostreatus and Pleurotus eryngii are mushrooms species worldwide consumed and able to Se bioaccumulate. However, depending on the level of this element, it can be toxic for the fungus. Here we showed that the presence of the Se in culture medium decreases fungal growth rate, hyphae diameter and septum distance and causes alteration in color of colony. A garlic strong smell was directly proportional to Se level. P. eryngii was more tolerant to Se than P. ostreatus. So, it is important to screen this element level for Se-enriched mushroom production.

关键词： Mushrooms Colony Morphology Food Sodium Selenite Hyphae Diameter