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121.
Georgios?Kountios Athanasios?RagkosEmail author Thomas?Bournaris Georgios?Papadavid Anastasios?Michailidis 《Precision Agriculture》2018,19(3):537-554
Precision agriculture (PA) constitutes a dynamic production method which is gaining attention in several parts of the world. Its environmental and economic sustainability has been examined in terms of its ability to reduce the adverse effects of agrochemical use—by regulating their application to the levels needed at the land parcel level—and of its contribution to higher incomes and profitability. At the social level, PA has been linked to collective action although little insight is available regarding the role of various actors and education. This study tackles PA through an assessment of the attitudes of farmers towards the elements of its sustainability and of their educational needs. The analysis of survey data of a sample of young farmers in Greece showed that the majority of respondents were not familiar with PA. Significant differences were found between the attitudes of knowledgeable and non-knowledgeable farmers, the former demonstrating better acknowledgement of the environmental, economic and social sustainability of PA. Important educational needs were also detected, with group and individual methods being the most preferred ones for education and information campaigns. The results of the analysis could be of use for the design of Common Agricultural Policy Pillar II measures for the promotion of PA targeting to specific audiences and actors. 相似文献
122.
Ioannis?GravalosEmail author Anastasios?Georgiadis Dimitrios?Kateris Theodoros?Gialamas Evagelos?Bompolas Zisis?Tsiropoulos Avgoustinos?Avgoustis Panagiotis?Xyradakis 《Precision Agriculture》2017,18(1):19-36
This research is a study on the relationship of irrigation water treatments and soil moisture distribution uniformity (DU). Soil moisture distribution was based on long-term data sets that were collected using a novel electromagnetic sensor-based platform moving inside sub-surface horizontal access-tubes. The research was conducted under controlled laboratory conditions in a soil tank. The irrigation treatments regarding two case studies under dry and wet soil conditions (from permanent wilting point to field capacity) were conducted for a period of 115 and 110 days respectively. In dry soil conditions, the irrigation water treatments strongly affect the DU of soil moisture that can be achieved constantly using non-uniform irrigation treatments. In contrast, the DU of soil moisture in wet soil conditions was maintained at a high percentage and was slightly affected by irrigation treatments. However, obtaining accurate soil moisture information at a large scale over a long period can be used to improve water use efficiency. 相似文献
123.
124.
A series of monoazo disperse dyes based on 2-amino-4-phenylthiazole was prepared using variousN,N-dialkylaniline derivatives as the coupling component. The dyes were characterized by IR spectral studies, visible absorption
spectroscopy and elemental analysis. The dyeing performance of these dyes was assessed on cellulose triacetate and nylon fibers.
These dyes were found to give a wide range of colour shades varying from bright red to royal blue with very good depth, brightness
and levelness on fibers. The dyed fibers showed good to very good light fastness and very good to excellent fastness to washing,
perspiration, rubbing and sublimation. The dyebath exhaustion and fixation on the fibers were found to be very good. 相似文献
125.
Henrik Harms Barbora Orlikova Seungwon Ji Damun Nesaei-Mosaferan Gabriele M. K?nig Marc Diederich 《Marine drugs》2015,13(8):4949-4966
The Ascomycota Dichotomomyces cejpii was isolated from the marine sponge Callyspongia cf. C. flammea. A new gliotoxin derivative, 6-acetylmonodethiogliotoxin (1) was obtained from fungal extracts. Compounds 2 and 3, methylthio-gliotoxin derivatives were formerly only known as semi-synthetic compounds and are here described as natural products. Additionally the polyketide heveadride (4) was isolated. Compounds 1, 2 and 4 dose-dependently down-regulated TNFα-induced NF-κB activity in human chronic myeloid leukemia cells with IC50s of 38.5 ± 1.2 µM, 65.7 ± 2.0 µM and 82.7 ± 11.3 µM, respectively. The molecular mechanism was studied with the most potent compound 1 and results indicate downstream inhibitory effects targeting binding of NF-κB to DNA. Compound 1 thus demonstrates potential of epimonothiodiketopiperazine-derived compounds for the development of NF-κB inhibitors. 相似文献
126.
Amaya-Guerra CA Alanis-Guzman MG Serna Saldívar SO 《Plant foods for human nutrition (Dordrecht, Netherlands)》2004,59(2):45-50
The physiological development of laboratory rats fed with a typical indigenous tortilla diet was studied for two generations. The experiment compared casein control diet and five different types of diets: (1) a diet of tortillas obtained from fresh masa (FM); (2) regular tortillas produced from enriched dry masa flour containing vitamins B1, B2, niacin, folic acid, and the microminerals iron and zinc (REDMF); (3) tortillas produced from enriched dry masa flour fortified with 6% defatted soybean meal (FEDMF); (4) tortillas produced from enriched quality protein maize flour (EQPM); and (5) and, tortillas produced from enriched quality protein maize flour fortified with 3% defatted soybean meal (FEQPM). The growth of rats fed FEDMF and FEQPM diets was significantly higher (P<0.05) in both generations than their counterparts fed EQPM, REDMF, or FM diet. Animals fed quality protein maize (QPM) tortilla had the highest protein digestibility, but the FEQPM and FEDMF diets had the highest biological value (BV), net protein utilization (NPU), and protein-digestibility-corrected EAA scores (PDCEAAS). The difference among treatments was more evident in the second-generation rats. The pregnancy rate, number of newborns/litter, litter weight, and newborn survival rate was also higher for rats fed FEDMF, EQPM, and FEQPM diets than their counterparts fed REDMF and FM. 相似文献
127.
The development of high tenacity, high modulus monofilaments from Polypropylene/Clay nanocomposite has been investigated.
Pure sodium montmorillonite nanoclay was modified using hexadecyl trimethyl ammonium bromide (HTAB) via an ion exchange reaction.
Pure and modified clay were characterized through X-ray diffraction, FTIR and TGA. The modified clay was melt blended with
polypropylene (PP) in presence of a swelling agent. Composite filaments from PP/Clay nanocomposite were prepared at different
weight percentages of nanoclay and the spinning and drawing conditions were optimized. The filaments were characterized for
their mechanical, morphological and thermal properties. The composite PP filaments with modified clay showed improved tensile
strength, modulus and reduced elongation at break. The composite filaments with unmodified clay did not show any improvement
in tensile strength but the modulus improved. The sharp and narrow X-ray diffraction peaks of PP/nanoclay composite filaments
indicate increase in crystallinity in presence of modified clay at small loadings (0.5%). The improved thermal stability was
observed in filaments with modified as well as unmodified clays. 相似文献
128.
Barbara M. Rezende Priscila T. T. Bernardes Carolina B. Resende Rosa M. E. Arantes Danielle G. Souza Fern?o C. Braga Marina G. M. Castor Mauro M. Teixeira Vanessa Pinho 《Marine drugs》2013,11(7):2595-2615
Lithothamnion muelleri (Hapalidiaceae) is a marine red alga, which is a member of a group of algae with anti-inflammatory, antitumor, and immunomodulatory properties. The present study evaluated the effects of treatment with Lithothamnion muelleri extract (LM) in a model of acute graft-versus-host disease (GVHD), using a model of adoptive splenocyte transfer from C57BL/6 donors into B6D2F1 recipient mice. Mice treated with LM showed reduced clinical signs of disease and mortality when compared with untreated mice. LM-treated mice had reduced tissue injury, less bacterial translocation, and decreased levels of proinflammatory cytokines and chemokines (interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), chemokine (C-C motif) ligand 2 (CCL2), chemokine (C-C motif) ligand 3 (CCL3) and chemokine (C-C motif) ligand 5 (CCL5)). The polysaccharide-rich fraction derived from LM could inhibit leukocyte rolling and adhesion in intestinal venules, as assessed by intravital microscopy. LM treatment did not impair the beneficial effects of graft-versus-leukaemia (GVL). Altogether, our studies suggest that treatment with Lithothamnion muelleri has a potential therapeutic application in GVHD treatment. 相似文献
129.
夷优180系福建省南平市农业科学研究所用自主选育的三系不育系夷A与恢复系南恢180配组而成的杂交中稻新品种。经多年在福建省各地试验、试种表现群体整齐、适应性广、产量高、抗性好等特点,2014年通过福建省农作物品种审定。简述了杂交水稻夷优180的选育及应用。 相似文献
130.
Xueli?Ding Yunfa?Qiao Timothy?Filley Haiying?Wang Xinxin?Lü Bin?ZhangEmail author Jingkuan?WangEmail author 《Biology and Fertility of Soils》2017,53(3):281-286
To test the impact of a range of long-term land use types on the partitioning of microbial residues among soil particles, samples from a Mollisol with plots under 100 years of continuous arable cropping, 30 years of simulated overgrazing to severely degraded bare soil, or 30 years of grassland restoration were investigated. The microbial residues, which were assessed among three particle-size fractions (<2, 2–20, and 20–250 μm) by amino sugar extraction, exhibited change with particle size and land use. Converting arable cropping to bare soil induced substantial depletion of amino sugars associated with the clay-size fraction, as a proportion of total carbon (C) and total soil mass, but not the silt- and sand-size fractions. Alternatively, switching arable soil to grassland increased amino sugar stocks in both the clay- and sand-size fractions. Analysis of the relative input of fungal and bacterial derived amino sugars indicated that fungal sources are the most dynamic with respect to land use change. These results highlight the selective vulnerability of microbial C pools in finer fractions under low plant C input and the selective recovery in specific fractions upon restoration, emphasizing the importance of the conversion of plant organic matter into mineral-associated microbial residues to promote stable soil organic C. 相似文献