户用分布式光伏对农户收入的影响——以中部地区Y县为例

户用分布式光伏对农户收入影响具有长期性,如何发挥分布式光伏在乡村振兴战略中的作用需进一步探索。本文以户用分布式光伏为例,利用中部地区Y县2014—2019年农户追踪数据,运用双重差分法,分析户用分布式光伏对农户收入的影响,探讨户用分布式光伏对农户收入影响的作用机制。结果表明,2014—2019年农户收入大幅度提升,其中建光伏农户的人均收入增长幅度大于未建光伏农户,户用分布式光伏使农户人均收入提高25.4%,其中经营性收入、财产性收入分别提高74.4%和444.5%,而工资性收入降低45.3%。户用分布式光伏是通过减少非农劳动时间和缩短非农就业空间距离降低农户工资性收入,增加经营性收入,从而影响人均收入。进一步分析发现,户用分布式光伏对非中心村农户的工资性收入和经营性收入影响大于中心村农户,劳动力能力越强的农户经营性收入上升幅度越大,工资性收入下降幅度越小。因此,建议统一维护光伏设施,促进劳动力要素有效配置;并依据劳动能力差异分层分配股份,降低劳动能力强的农户对政府补贴的依赖;另外,创新光伏产业发展模式,拓宽光伏产业增收渠道。     

Oxygen uptake in the Antarctic teleost Pagothenia borchgrevinki. Limitations imposed by X-cell gill disease

Fish in a population of Pagothenia borchgrevinki in McMurdo Sound, Antarctica, are affected by a gill disease (X-cell disease) which causes tissue hyperplasia that results in a decreased gill surface area and an increased water/blood diffusion distance. P. borchgrevinki acquires 95% of its oxygen via the gills, but damage to the gills by X-cell disease did not affect this function. There was no compensatory shift to cutaneous respiration. X-cell disease reduced the ability for oxygen uptake at low ambient P_{O 2} and the decreased uptake was related to the extent of the disease. _{O 2} max was greatly reduced in X-cell affected fish and substantially reduced their aerobic potential. This effect may impair the ability of diseased fish to catch prey and avoid predators.     

Long-term nutritional effects on the primary liver and kidney metabolism in rainbow trout (Oncorhynchus mykiss). II. Adaptive response of glucose 6-phosphate dehydrogenase activity to high-carbohydrate/low-protein and high-fat/non-carbohydrate diets

The influence of long-term administration of high-carbohydrate/low-protein and high-fat/non-carbohydrate diets were studied in relation to kinetic behaviour of glucose 6-phosphate dehydrogenase in liver and kidney of rainbow trout. In all cases studied, the saturation curves of these enzyme showed typical hyperbolic kinetics without evidence of sigmoidicity. After 30 days of feeding with a high-fat diet (170 g kg^?1), there was a significant decrease in V_max and specific activity (45%) as well as catalytic efficiency (39%) without changes in K_m or activity ratio of hepatic glucose 6-phosphate dehydrogenase. These changes agree more with a clearly decreased cell concentration than with an inhibition of the pre-existing enzyme. The administration of a high-carbohydrate diet (60 g kg^?1), contrary to what was previously thought, decreased V_max by 21% and specific activity and catalytic efficiency by 30%, without significant changes in the other kinetic parameters of the hepatic enzyme. The kinetic behaviour under these nutritional conditons was due to the rejection of this diet by the fish and thus could be considered a low-feeding situation. On the other hand, no variations in the kinetics of renal glucose 6-phosphate dehydrogenase were found, clearly demonstrating that in this organ, the pentosephosphate pathway showed no adaptive response related to fattyacid and other lipid synthesis. The activity of the renal enzyme was consistently half that of the hepatic enzyme.     

Endocrine changes in the fowl during infection with Eimeria maxima

Plasma concentrations of thyroxine (T4), triiodothyronine (T3), prolactin, growth hormone and corticosterone were measured in immature domestic fowl which were infected with Eimeria maxima, uninfected but given the same amount of food as those infected (pair-fed) or fed ad libitum. Infection with E maxima caused a decrease in plasma T4 concentration whereas pair feeding caused an increase when food intake was minimal. Plasma T3 concentrations were decreased similarly in both infected and pair-fed birds. Infection caused an increase in plasma prolactin concentration, whereas pair-feeding did not. The plasma concentration of growth hormone was not affected by any of the treatments. Plasma corticosterone concentration was markedly increased on days 5 and 6 in pair-fed birds but was not affected by infection with E maxima.     

Proteins in denaturing solvents: gel exclusion studies

Many proteins are fully denatured and separated into component polypeptide chains in 6M guanidine hydrochloride containing mercaptoethanol and a chelating agent. In this and similar denaturing solvents, polypeptide chains of molecular weights from 2,000 to 100,000 can be eluted from 6 percent agarose columns and separated according to molecular weight. By this procedure molecular weights may be assigned to proteins (including many normally insoluble in nondenaturing solvents) without the uncertainties that arise when native molecules of unknown shape are studied.     

Chimeric and ex-parabiotic frogs (Rana pipiens): specificity of tolerance

Rejection of orthotopic neural-fold transplants may be prevented by either embryonic parabiosis or reciprocal exchange of presumptive blood. These observations form the basis of the no blood-no tolerance hypothesis, which states that persistent tolerance by the host requires that the somatic transplant be accompanied by presumptive blood from the donor. Regarding parabionts and chimeras as special cases of transplantation of whole or partial animals, I found that ex-parabionts accept subsequent skin exchanges only from the homologous ex-parabiont; reciprocal chimeras are compatible provided each animal portion contains a primary blood source, and will accept transplants as frogs only from the homologous recombinant. Chimeric recombinations made anterior to the heart field prove incompatible and fail to survive to maturity. Successful chimeras as well as ex-parabionts survive to maturity and are apparently normal in every antigen, radiation, and drugs.     

Systemic mucormycosis in a hooded seal (Cystophora cristata)

A 4-yr-old male captive hooded seal (Cystophora cristata), previously diagnosed as hypothyroid, died after a 3-wk period of lethargy and inappetance despite treatment that included intramuscular administration of antibiotics and multivitamins. Gross pathologic findings included extensive muscle necrosis over the left flank, an underlying necrotic iliac lymph node, two necrotic pulmonary masses and a necrotic bronchial lymph node. Routine cultures yielded a number of bacterial isolates and a heavy pure fungal growth from the necrotic iliac lymph node; wet preparations of which revealed sporangiophores typical of Mucor sp. Histopathology of necrotic muscle, pulmonary lesions and bronchial and iliac lymph nodes revealed necrosis with a marked pyogranulomatous and eosinophilic inflammatory cell infiltrate and fungal hyphae consistent with a Zygomycete species. This is believed to be the first report of systemic mucormycosis in a pinniped likely to have originated from an injection site reaction.     

RELATION OF SEVERAL PEDOLOGICAL CHARACTERISTICS TO ENGINEERING QUALITIES OF SOIL

An attempt to predict engineering qualities which are needed in soil evaluation and to enhance nonagricultural use of soil survey data was made. Data from a variety of soils were subjected to simple correlation and multiple regression analyses to relate three pedologic characteristics: clay content, cation-exchange capacity (CEC), and organic matter content to two engineering qualitites: plasticity index, and optimum moisture. Simple correlation coefficients showed that clay content and CEC correlated significantly with the engineering determinations. The relationship between organic matter content and these engineering determinations was weaker. Multiple regression analyses showed that the three pedologic characteristics accounted for most of the variation in each of the engineering qualities, and that prediction was feasible.