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81.
Information is key in reducing the uncertainties of sustainable agricultural practices (SAPs). The objective of this study was to improve the understanding of the relationship between utilized informational sources and other key identified factors affecting Malaysian vegetable producers' choices. The findings of a multivariate probit model suggest that information sources are complementary. The choices for these sources are influenced by heterogeneity in access to credit, social network (member of farmers association), and farm settings (distance from farm to market, resource depletion issues, and geographical regions). Future promotion of SAPs should be delivered through the provision of quality content disseminated through the preferred information sources, which target potential users.  相似文献   
82.
Electroreduction of carbon dioxide (CO(2))--a key component of artificial photosynthesis--has largely been stymied by the impractically high overpotentials necessary to drive the process. We report an electrocatalytic system that reduces CO(2) to carbon monoxide (CO) at overpotentials below 0.2 volt. The system relies on an ionic liquid electrolyte to lower the energy of the (CO(2))(-) intermediate, most likely by complexation, and thereby lower the initial reduction barrier. The silver cathode then catalyzes formation of the final products. Formation of gaseous CO is first observed at an applied voltage of 1.5 volts, just slightly above the minimum (i.e., equilibrium) voltage of 1.33 volts. The system continued producing CO for at least 7 hours at Faradaic efficiencies greater than 96%.  相似文献   
83.
Interactions with other responsive agents lie at the core of all social exchange. During a social exchange with a partner, one fundamental variable that must be computed correctly is who gets credit for a shared outcome; this assignment is crucial for deciding on an optimal level of cooperation that avoids simple exploitation. We carried out an iterated, two-person economic exchange and made simultaneous hemodynamic measurements from each player's brain. These joint measurements revealed agent-specific responses in the social domain ("me" and "not me") arranged in a systematic spatial pattern along the cingulate cortex. This systematic response pattern did not depend on metrical aspects of the exchange, and it disappeared completely in the absence of a responding partner.  相似文献   
84.
Electrically conductive substrates with chromic behavior are prepared using conductive polymer coating of the substrate. Poly (3-methylthiophene) (P3MT) — coated polyester fabric with specific electrical and chromic properties, for instance electrochromic and piezochromic behavior, was successfully obtained by chemical polymerization with the help of continuous and speed stirring technique. The effect of polymerization time, temperature and oxidant concentration on conductivity of the P3MT-coated fabric was studied. The presence of P3MT particles on the surface of the coated substrate was confirmed by scanning electron microscopy (SEM), fourier transform infrared (FTIR) and UV-Vis spectroscopy, electrical surface resistivity, pressure and applied voltage dependence visible reflectance spectrophotometer measurements, and X-ray diffraction (XRD) analysis. The blue shift of c95 nm in wavelength of maximum absorption observed in the reflectance spectra of coated polyester fabric. Under high pressure, the P3MT-coated polyester fabric demonstrated piezochromism. The coated substrate also showed electrochromic behavior under an electrical applied voltage of 12 V.  相似文献   
85.
Conventional theory for color matching is Kubelka-Munk, but it fails in some situations. New intelligent procedures such as neural networks could learn the behavior of a complex system and produce accurate prediction. This paper investigates the ability of MLP (multiple layer perceptron) neural network for color matching of cotton fabric. Three reactive dyes, namely Levafix Red CA, Levafix Yellow CA and Levafix Blue CA were used for experiments. The dyed samples were scanned and L * a * b * histogram were extracted. Different neural networks were trained and tested using L * a * b * histogram of fabric’s images and also L * a * b * values (D65, 10°) of fabrics. The results were encouraging. For neural networks including the L * a * b * histogram in input vector, colorants and their concentration were predicted with a mean square error (MSE) less than 10?5 and an average value of color difference (CMC (1:2)) less than 1.5 for approximately 80 % of testing data.  相似文献   
86.
In the current paper, we fabricated, characterized, and applied nanocomposite hydrogel based on alginate (Alg) and nano-hydroxyapatite (nHA) loaded with phenolic purified extracts from the aerial part of Linum usitatissimum (LOH) as the bone tissue engineering scaffold. nHA was synthesized based on the wet chemical technique/precipitation reaction and incorporated into Alg hydrogel as the filler via physical cross-linking. The characterizations (SEM, DLS, and Zeta potential) revealed that the synthesized nHA possess a plate-like shape with nanometric dimensions. The fabricated nanocomposite has a porous architecture with interconnected pores. The average pore size was in the range of 100–200 µm and the porosity range of 80–90%. The LOH release measurement showed that about 90% of the loaded drug was released within 12 h followed by a sustained release over 48 h. The in vitro assessments showed that the nanocomposite possesses significant antioxidant activity promoting bone regeneration. The hemolysis induction measurement showed that the nanocomposites were hemocompatible with negligible hemolysis induction. The cell viability/proliferation confirmed the biocompatibility of the nanocomposites, which induced proliferative effects in a dose-dependent manner. This study revealed the fabricated nanocomposites are bioactive and osteoactive applicable for bone tissue engineering applications.  相似文献   
87.
Submergence tolerant high yielding rice variety was developed using BR11 as a recipient parent applying foreground, phenotypic and background selection approaches. Recombinant selection was found essential to minimize linkage drag by BC2F2 generation. Without recombinant selection, the introgression size in the backcross recombinant lines(BRLs) was approximately 15 Mb on the carrier chromosome. The BRLs were found submergence tolerance compared to the check varieties under complete submergence for two weeks at Bangladesh Rice Research Institute, and produced higher yield compared to the isogenic Sub1-line under control ed submerged condition. The BRL IR85260-66-654-Gaz2 was released as BRRI dhan52 in 2010, which was the first high yielding submergence tolerant variety in Bangladesh. BRRI dhan52 produced grain yield ranging from 4.2 to 5.2 t/hm2 under different flash flood prone areas of Bangladesh in three consecutive seasons. The study demonstrated the efficiency of recombinant selection and better adaptability of the newly released submergence tolerant high yielding variety in flash flood prone different areas of the country with respect to submergence tolerance and yield potential.  相似文献   
88.

Ornamental fish farming is globally a key sector of aquaculture. The purpose of this study was to report on the parasitic fauna of ornamental fish from seven farms in the East Azerbaijan province in northwestern Iran. Between November 2020 and February 2021, a total of 600 freshwater ornamental fish of six species, including goldfish (Carassius auratus), angel (Pterophyllum scalare), guppy (Poecilia reticulata), dwarf gourami (Colisa lalia), swordtail (Xiphophorus helleri), and cichlid (Cichlasoma sp.) were collected for parasitological analysis. Six ciliate protozoan species (Trichodina mutabilis, Trichodina nobilis, Trichodina spp., Heteropolaria lwoffi, Ichthyophthrius multifiliis, and Chilodonella spp.), three species of monogenean trematodes (Dactylogyrus dulkeiti, Dactylogyrus spp. and Gyrodactylus spp.), two species of crustacean arthropods (Lernaea cyprinacea and Argulus japonicus), and a nematode (Capillaria spp.) were identified among the examined fish. Parasites were detected in the fish from 5 of 7 farms, with an overall parasitic prevalence in 26.33% (158/600) of the fish. Fish infection rates with protozoans, monogenean trematodes, crustacean arthropods, and nematodes were 16.83, 13.17, 4, and 0.33% respectively. The highest prevalence was found in X. helleri infected with Gyrodactylus spp. and P. scalare infested with Trichodina spp. Moreover, 9/100 and 10/100 of goldfish were infected with A. japonicus and L. cyprinacea, compared to 2/500 and 3/500, respectively, for all other species in combination, which is a statistically significant result (p?<?0.01). Assessment of farmed fish parasitic fauna is important to inhibit the spread of infections, ensure fish production and improve fish health.

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89.
BACKGROUND: To check for correlation between the insecticidal properties and the specificity of lectins, a comparative study was made of the insecticidal activities of two garlic lectins with different biological activities.RESULTS: The insecticidal activity of the garlic (Allium sativum L.) leaf lectin ASAL and bulb lectin ASAII towards the tobacco aphid Myzus nicotianae Blackman was studied using bioassays with transgenic tobacco (Nicotiana tabacum L. cv. Wisconsin 38). Bioassays were started with newborn nymphs of the tobacco aphid. Although during the first 7-8 days when nymphs developed to adults there were no apparent effects, part of the nymphal population was found to develop into winged (alate) forms. Later it became clear that transgenic plants expressing ASAL and ASAII had a significant effect on the reproduction capacity of the resulting adults, with a reduction of up to 40%. Different life table parameters such as prereproductive time, intrinsic rate of natural increase, generation time and doubling time were significantly affected (P < 0.05) in aphids grown on transgenic plant material expressing ASAL and ASAII.CONCLUSION: Bioassays with tobacco plants expressing ASAL and ASAII demonstrated a significant impact on the population growth of M. nicotianae. Therefore, both lectins can be considered as valuable candidate aphid control agents.  相似文献   
90.
The present study was undertaken to evaluate the effects of feeding the male mice with miso that was prepared with a mixture of microbial starters on the level of lipid peroxidation as a marker of oxidative stress, antioxidant power of hepatocytes, the enzymatic and non-enzymatic antioxidant. The starters that were used in the preparation of miso were Aspergillus oryzae and Pleurotus ostreaus or A. oryzae and Bacillus subtilis. The miso that was prepared with A. oryzae and Bacillus subtilis has more effect on suppressing the oxidative stress and enhancement of endogenous antioxidant of hepatocytes and renal tissue of mice.  相似文献   
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