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81.
Amin Setyo Leksono Kenta Takada Nobukazu Nakagoshi Koji Nakamura 《Journal of Forest Research》2006,11(1):61-64
A continuous sampling of canopy beetles was carried out to determine variations in the abundance, species diversity, richness,
and composition of the Mordellidae and Cerambycidae in a coppice woodland. Changes in the abundance and the species richness
were monitored at three heights in the forest throughout the season in 1999, using yellow and blue water pan traps. The results
showed significant variations in the abundance of Mordellidae among the canopy layers, while little variation was found for
Cerambycidae. The abundance, species diversity, and richness were generally greater in summer. The results showed distinct
species compositions in both families among layers. 相似文献
82.
Nagamine MK Sanches DS Pinello KC Torres LN Mennecier G Latorre AO Fukumasu H Dagli ML 《Veterinary research communications》2011,35(6):391-399
Mast cell tumor (MCT) is one of the most prevalent neoplasms that affect skin and soft tissue in dogs. Because mast cell tumors
present a great variety of clinical appearance and behavior, their treatment becomes a challenge. Trichostatin A (TSA), an
antifungal antibiotic, has shown inhibitory effects on the proliferation and induction of apoptosis in various types of cancer
cells. In order to evaluate the potential of trichostatin A as a therapeutic drug, cells of grade 3 MCT were cultured and
treated with concentrations of 1 nM to 400 nM of TSA. MTT assay and trypan blue exclusion assays were performed to estimate
cell growth and cell viability, and cell cycle analysis was evaluated. TSA treatment showed a reduction in numbers of viable
cells and an increase of cell death by apoptosis. The cell cycle analysis showed an increase of hypodiploid cells and a reduction
of G0/G1 and G2/M –phases. According to these results, trichostatin A may be an interesting potential chemotherapeutic agent
for the treatment of canine MCT. 相似文献
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84.
Path analysis for selection of drought tolerant sugarcane genotypes through physiological components
Paulo Pedro da Silva Lailton SoaresJoão Gomes da Costa Luciana da Silva VianaJúlio César Farias de Andrade Eduardo Rebelo GonçalvesJoão Messias dos Santos Geraldo Veríssimo de Souza BarbosaVelber Xavier Nascimento Adriana Reis TodaroAlessandro Riffel Maria Fatima Grossi-de-SaMárcio Henrique Pereira Barbosa Antônio Euzébio Goulart Sant’AnaCícero Eduardo Ramalho Neto 《Industrial Crops and Products》2012,37(1):11-19
Water deficit is among the main environmental factors limiting agricultural productivity of sugarcane in Northeast Brazil by affecting virtually every aspect of plant growth, with consequent reduction of the agro-industrial productivity of this crop. This study aimed to use path analysis to evaluate the physiological components of sugarcane under two water conditions, with photosynthesis as the basic variable, in order to obtain subsidies that can help the genetic breeding of this crop by selection of superior clones with drought tolerance. The experiment was carried out in a greenhouse with a completely randomized experimental design, 4 × 2 factorial arrangements (four sugarcane genotypes × two soil moisture regimes: control, with 80-100% available water and stressed, with 0-20% water available) and with four replications. Each plot consisted of one pot with 12 kg of substrate containing one plant. Treatments were maintained at a humidity close to field capacity with daily replacement of the evapotranspired water with a water supply for 66 days of cultivation for treatments under stress. Evaluations were conducted on the fourth day after severe water stress at 70 days of cultivation. Data from nine physiological variables were considered, with six of these being used in the model after exclusion of those that were contributing to multicollinearity. Variables used in path analysis were enough to explain the variation found in photosynthesis under both water conditions. Stomatal conductance, transpiration and the SPAD index should be considered as a priority in breeding programs for sugarcane aiming to get more productive and tolerant genotypes to water stress, and selection indexes should be used with due consideration of these variables to promote gains in photosynthesis. 相似文献
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86.
Theodore W. Hermann Fabrice Duponchelle Leandro Castello Karin E. Limburg Luciana A. Pereira Marília Hauser 《水产资源保护:海洋与淡水生态系统》2021,31(12):1206-1220
- Freshwater environments host roughly half of the world’s fish diversity, much of which is concentrated in large, tropical river systems such as the Amazon. Fishes are critical to ecosystem functioning in the Amazon River basin but face increasing human threats. The basic biology of these species, and particularly migratory behaviour, remains poorly studied, in part owing to the difficulty associated with conducting tagging studies in remote tropical regions.
- Otolith microchemistry can circumvent logistical issues and is an increasingly important tool for studying fish life histories. However, this approach is still new in the Amazon, and its potential and limitations to inform fish conservation strategies remain unclear.
- Here, otolith microchemistry studies in the Amazon are reviewed, highlighting current possibilities, and several key factors that limit its use as a conservation tool in the Amazon are discussed. These include the dearth of spatiotemporal elemental data, poor understanding of environment–fish–otolith pathways, and insufficient funding, facilities, and equipment.
- A research initiative is proposed to harness the potential of this technique to support conservation in the Amazon. Key aspects of the proposal include recommendations for internal and external funding, which are critical to acquiring and maintaining technical staff, cutting-edge equipment, and facilities, as well as fostering regular scientific meetings and working groups. Meetings can facilitate a systematic approach to investigating environment–otolith pathways, broadening the chemical baseline for most Amazonian tributaries, and exploring potential valuable elements.
- These outcomes are urgently needed to conserve biodiversity and ecosystem functioning in the Amazon, especially given threats such as widespread hydroelectric damming. The initiative proposed here could make otolith microchemistry an important, cost-effective tool to inform and foster conservation in the Amazon, and act as a template for other imperilled tropical river basins, such as the Mekong and the Congo.
87.
de Almeida Daniel Mageste Marcondes Marcos Inácio Rennó Luciana Navajas Pereira Silva Luiz Henrique Martins Leandro Soares Marquez David Esteban Contreras Castaño Villadiego Faider Alberto Velez Saldarriaga Felipe Franco Julian David Castaño Moreno Deilen Paff Sotelo de Moura Felipe Henrique Paulino Mário Fonseca 《Tropical animal health and production》2019,51(1):79-87
Tropical Animal Health and Production - The objective of this study was to evaluate the effects of strategic supplementation in the dry period and dry/rainy transition period on the performance and... 相似文献
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