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排序方式: 共有173条查询结果,搜索用时 15 毫秒
1.
Ana M. Casas Carlota R. Gazulla Arantxa Monteagudo Carlos P. Cantalapiedra Marian Moralejo M. Pilar Gracia Francisco J. Ciudad William T.B. Thomas José L. Molina-Cano Scott Boden Bruno Contreras-Moreira Ernesto Igartua 《作物学报(英文版)》2021,(4):862-872
Response to vernalization and photoperiod are the main determinants controlling the time to flowering in temperate cereals. While the individual genes that dete... 相似文献
2.
Teresa Mosquera Vásquez Sara Del Castillo David Cuéllar Gálvez Luis Ernesto Rodríguez 《Potato Research》2017,60(3-4):361-381
Global challenges like sustainable development, climate change, malnutrition and gender inequality can be tackled from an agricultural perspective. Micronutrient deficiency is a major problem for the health and food security of the population. In Colombia, iron deficiencies affect 32% of the children under the age of five; and 43% of the Colombian population have zinc and vitamin A deficiencies. We designed and implemented a research-for-development programme that links agriculture and nutrition through a two-stage project. In the first stage, we selected three new yellow potato cultivars with better nutritional contents, higher yield and better resistance to late blight than the traditional yellow cultivars. We characterized the Colombian germplasm, Solanum tuberosum Group Phureja, for its nutritional attributes. During this stage, studies of the social and nutritional status of the communities were also conducted. In the second stage, we focused on scaling up new potato cultivars to reach potato producers and consumers by promoting the production and marketing of good quality seed potatoes, by establishing four Rural Entrepreneurs Nuclei. The programme promotes gender equity, good dietary habits, the consumption of more nutritious potatoes and empowers local leadership to strengthen governance. Field work was conducted in southern and central regions of Colombia by employing social strategies such as the Family Farming Community Schools. In 50% of the cultivated area, we are replacing the originally used traditional yellow potatoes by the new, more nutritious, potatoes to reach 6 million consumers. A good quality seed system for small-scale potato growers has been implemented. These achievements have been reached through a comprehensive approach in a period of two years. 相似文献
3.
Dongchen An Ernesto Lopes Pinheiro-Junior Lszl Bress Irina Gladkikh Elena Leychenko Eivind A. B. Undheim Steve Peigneur Jan Tytgat 《Marine drugs》2022,20(2)
(1) Background: G protein-coupled inward-rectifier potassium (GIRK) channels, especially neuronal GIRK1/2 channels, have been the focus of intense research interest for developing drugs against brain diseases. In this context, venom peptides that selectively activate GIRK channels can be seen as a new source for drug development. Here, we report on the identification and electrophysiological characterization of a novel activator of GIRK1/2 channels, AsKC11, found in the venom of the sea anemone Anemonia sulcata. (2) Methods: AsKC11 was purified from the sea anemone venom by reverse-phase chromatography and the sequence was identified by mass spectrometry. Using the two-electrode voltage-clamp technique, the activity of AsKC11 on GIRK1/2 channels was studied and its selectivity for other potassium channels was investigated. (3) Results: AsKC11, a Kunitz peptide found in the venom of A. sulcata, is the first peptide shown to directly activate neuronal GIRK1/2 channels independent from Gi/o protein activity, without affecting the inward-rectifier potassium channel (IRK1) and with only a minor effect on KV1.6 channels. Thus, AsKC11 is a novel activator of GIRK channels resulting in larger K+ currents because of an increased chord conductance. (4) Conclusions: These discoveries provide new insights into a novel class of GIRK activators. 相似文献
4.
Ernesto Lopes Pinheiro-Junior Rimma Kalina Irina Gladkikh Elena Leychenko Jan Tytgat Steve Peigneur 《Marine drugs》2022,20(2)
Sea anemones are a rich source of biologically active compounds. Among approximately 1100 species described so far, Heteractis crispa species, also known as sebae anemone, is native to the Indo-Pacific area. As part of its venom components, the Hcr 1b-2 peptide was first described as an ASIC1a and ASIC3 inhibitor. Using Xenopus laevis oocytes and the two-electrode voltage-clamp technique, in the present work we describe the remarkable lack of selectivity of this toxin. Besides the acid-sensing ion channels previously described, we identified 26 new targets of this peptide, comprising 14 voltage-gated potassium channels, 9 voltage-gated sodium channels, and 3 voltage-gated calcium channels. Among them, Hcr 1b-2 is the first sea anemone peptide described to interact with isoforms from the Kv7 family and T-type Cav channels. Taken together, the diversity of Hcr 1b-2 targets turns this toxin into an interesting tool to study different types of ion channels, as well as a prototype to develop new and more specific ion channel ligands. 相似文献
5.
Maria Excelsis M. ORDEN Wilfred E. JAMANDRE Ernesto O. BROWN Edgar A. ORDEN Emilio M. CRUZ Ana Marie P. ALO Edwin C. VILLAR 《Animal Science Journal》2005,76(2):179-185
Preference for goat characteristics was determined from 42 traders in six markets in Pangasinan, an important trading center for goats in Luzon, the Philippines, and analyzed using a hedonic price model to determine whether these characteristics are important price determinants of goats. This information is important to goat raisers to respond to the needs of the local market, and thus to achieve a better price and higher income in goat raising. Meatiness, size, breed, sex and age (in descending order) were the dominant goat characteristics preferred by traders. Meatiness had the largest positive influence on price, with a price premium of US$6.24 (US$1.00 = PhP 53), whereas the age of the animal had the smallest influence at US$3.72. However, size and meatiness are manifestations of good breeds. Therefore, continued efforts to improve breeds in order to produce good quality goats are imperative to cater to market needs. Different characteristics implied different price premiums. Traders offered a higher price premium for better goat characteristics; thus, the improvement of these characteristics could result in higher returns for goat raisers. 相似文献
6.
Christopher J Bonar Ernesto O Boede Manuel García Hartmann Joanne Lowenstein-Whaley Esmeralda Mujica-Jorquera Scott V Parish James V Parish Michael M Garner Cynthia K Stadler 《Journal of zoo and wildlife medicine》2007,38(2):177-191
River dolphins are especially susceptible to negative human impacts. For their conservation, attempts of relocation or procreation ex situ may become important in the future to avoid their extinction. Additional knowledge and medical experiences of river dolphin management in captivity may aid such conservation efforts. The medical records and necropsy and histopathology reports on 123 captive Amazon River dolphins (Inia geoffrensis) were re-viewed. Of these 123 animals, 105 were necropsied and 70 necropsies were supported with histopathology. Eighteen animals were not necropsied. Among wild-born animals, mortality was highest in the first 2 mo immediately postcapture and transport, accounting for 32 of 123 deaths. Pneumonia and skin lesions (cutaneous and subcutaneous ulcerations and abscesses) were the most common findings, found in 44 of 105 (42%) and 38 of 105 (36%) of gross diagnoses, respectively. At least 10 of 44 cases of pneumonia diagnosed grossly included a verminous component. Cachexia, from a variety of causes, was a major gross finding in 21 animals. Fifteen animals had histologic evidence of significant renal pathology, and this was the primary cause of death in 13 cases. Hepatic pathology was found in 18 cases, and bacterial sepsis was confirmed via histology in 16 cases. Based on these findings, it may be concluded that keys to successful maintenance of this species include 1) prophylactic anthelminthic and antibiotic therapy immediately post-capture; 2) maintenance of animals in larger enclosures than in past attempts, in compatible groups, and in facilities capable of separating aggressive animals; 3) maintenance in microbiologically hygienic water quality at all times; and 4) a proactive program of preventive medicine during the immediate postcapture, quarantine, and maintenance period of captivity. 相似文献
7.
Cardozo Ernesto Gómez Celentano Danielle Rousseau Guillaume Xavier Silva Hulda Rocha e Muchavisoy Henry Mavisoy Gehring Christoph 《Agroforestry Systems》2022,96(5-6):941-956
Agroforestry Systems - The potential of agroforestry systems (AFS) for atmospheric carbon sequestration in degraded tropical lands is of key interest for climate change and rural development... 相似文献
8.
Contribution of family labour to the profitability and competitiveness of small-scale dairy production systems in central Mexico 总被引:1,自引:1,他引:0
Rodolfo Rogelio Posadas-Domínguez Carlos Manuel Arriaga-Jordán Francisco Ernesto Martínez-Castañeda 《Tropical animal health and production》2014,46(1):235-240
The objective of this work was to determine the effect of family labour on the profitability and competitiveness of small-scale dairy farms in the highlands of Central Mexico. Economic data from 37 farms were analysed from a stratified statistical sampling with a Neyman assignment. Three strata were defined taking herd size as criterion. Stratum 1: herds from 3 to 9 cows plus replacements, Stratum 2: herds from 10 to 19 cows and Stratum 3: herds from 20 to 30 cows. The policy analysis matrix was used as the method to determine profitability and competitiveness. The coefficient of private profitability (CPP) when the economic cost of family labour is included in the cost structure was 8.0 %, 31.0 % and 46.0 %. When the economic cost of family labour is not included, CPP increase to 47.0 %, 57.0 % and 66.0 % for each strata, respectively. The private cost ratio (PCR) when family labour is included was 0.79, 0.51 and 0.42 for strata 1, 2 and 3, respectively. When family labour is not included, the PCR was 0.07, 0.25 and 0.26. Net profit per litre of milk including family labour was US$0.03 l-1 for Stratum 1, US$0.09 for Stratum 2 and US$0.12 l-1 for Stratum 3; but increased to $0.12, 0.14 and 0.15, respectively, when the economic cost of family labour is not included. It is concluded that family labour is a crucial factor in the profitability and competitiveness of small-scale dairy production. 相似文献
9.
Miguel A Hurtado Ilie S Racotta Olivia Arjona Mónica Hernández-Rodríguez Ernesto Goytortúa Roberto Civera & Elena Palacios 《Aquaculture Research》2006,37(13):1316-1326
Litopenaeus vannamei (Boone) grown in ponds are exposed to salinities of less than 5 g L?1 during inland shrimp culture or to more than 40 g L?1 from evaporation and reduced water exchange in dry, hot climates. However, dietary requirements for shrimp grown in low or high salinities are not well defined, particularly for fatty acids. Feeding shrimp postlarvae with highly unsaturated fatty acids (HUFA) enhances tolerance to acute exposure to low salinity, as a result of better nutritional status, or/and specific effects of HUFA on membrane function and osmoregulation mechanisms. This study analysed the effect of HUFA supplementation (3% vs. 34%) on L. vannamei juveniles reared for 21 days at low (5 g L?1), medium (30 g L?1) and high salinities (50 g L?1). Juveniles grown at 5 g L?1 had lower survival compared with controls (30 g L?1) or shrimp grown at 50 g L?1, but no significant effect on survival was observed as a result of HUFA enrichment. In contrast, growth was significantly lower for shrimp grown at 50 g L?1, but this effect was compensated by the HUFA‐enriched diet. Osmotic pressure in haemolymph was affected by salinity, but not by HUFA enrichment. Shrimp fed HUFA‐enriched diets had significantly higher levels of eicosapentaenoic acid and docosahexaenoic acid in hepatopancreas and gills. These results demonstrate that growth at high salinities is enhanced with diets containing high HUFA levels, but that HUFA‐enriched diets have no effect on shrimp reared at low salinities. 相似文献
10.
The effects of woody residues from Eucalyptus globulus Labill. plantations on N losses were assessed through a lysimetric experiment. Treatments were: (NW) forest floor litter and non-woody residues (leaves, bark, twigs) incorporated into the soil; (IP) as NW plus woody residues (branches) cut in 20-cm long pieces and incorporated into the soil; (IC) as IP, but with branches chopped into chips; (SP) non-woody and woody residues (pieces) placed on the soil surface; (SC) as SP plus branches chopped into chips; and (CT) absence of organic residues. Leaching of N-NO 3 ? and N-NH 4 + was followed during a six-year period and N mineralization was evaluated at the end of the experiment. Non-woody residues enhanced N leaching as compared with the control. Conversely, woody residues decreased N losses. Although differences between treatments were not significant at the end of the experiment, incorporation and fragmentation of woody residues resulted in the more favourable management option regarding the reduction of N leaching observed at short-term. As high amounts of residues were used, the effect observed on decrease N leaching could be higher than that existing in Portuguese eucalypt plantations. 相似文献