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1.
Journal of Plant Diseases and Protection - Sclerotinia stem rot (SSR), caused by Sclerotinia sclerotiorum (Lib.) De Bary, is one of the most devastating diseases of tomato. The control of the...  相似文献   
2.
The anti-diarrheal activity of methanol extract of dried bark and aerial parts of Litsea polyantha (MELP) has been evaluated in mice using different models (castor oil-induced diarrhea and propulsive gut motility in mice). MELP (50, 75, 100 mg/kg, p.o.) significantly (P<0.01) reduced the onset of diarrhea, fecal excretion and also showed a significant (P<0.001) reduction in gastrointestinal motility on charcoal meal test in mice. The results of the study support the folklore use of the plant for diarrheal remedies.  相似文献   
3.
Heart sound recordings were taken from cats. The heart sounds were recorded directly from the chest wall and through an esophageal tube. The phono transducer and the esophageal tube were both placed over the base of the heart. Ultrasound M-mode, or motion-mode, recordings were taken to study the mitral valve dynamics. After analogue to digital conversion, electrocardiogram gated first heart sounds of each phono record were analyzed by the fast Fourier transform to obtain a frequency spectrum. Relative energies in 15 Hz bandwidths up to 150 Hz were correlated with the mitral valve closing velocity of the anterior mitral leaflet, obtained from the M-mode echocardiograms. The closing velocity correlated best with the energy in the 30-45 Hz bandwidth and 60-75 Hz bandwidth for the externally and internally monitored phonocardiogram respectively. The chest wall acted as a low pass filter, that is, the wall favoured the transmission of low frequencies and the energy transmitted decreased as wall thickness increased.  相似文献   
4.
Ultrastructural localization of neuronal nitric oxide synthase (nNOS) in olfactory receptor neurons (ORNs) and immunohistochemical detection of the enzyme in forebrain, pituitary, and pineal were undertaken in the teleost Oreochromis mossambicus. Application of post-embedding immunoelectron microscopy revealed nNOS-labeled gold particles on the cilia, microvilli, mitochondria, and Golgi complex of the ORNs. Gold particles were also seen adhered to microtubules in the axons that extend to the olfactory nerve layer in the olfactory bulb. With light microscopy, nNOS-immunoreactive neurons were seen in preoptic area, nucleus entopeduncularis, and parvocellular, and magnocellular subdivisions of nucleus preopticus (NPO). Numerous cerebrospinal fluid-contacting cells lining the wall of the third ventricle at the level of the NPO showed intense immunoreactivity. Intense to moderate immunoreactivity was observed in the neurons of suprachiasmatic nucleus, nucleus lateralis tuberis pars lateralis, and nucleus recessus lateralis. While several immunoreactive fibers were detected in medial olfactory tract, suprachiasmatic area, and hypothalamo-hypophyseal tract, a few were seen throughout the telencephalon, in the optic chiasma, tuberal area, and inferior lobes. In the pituitary, nNOS-containing fibers were seen in the neurohypophysis, rostral pars distalis, proximal pars distalis, and pars intermedia. While intense immunoreactivity was noticed in some cells in the pineal, immunoreactive fibers were detected in the pineal stalk as well as parenchyma. We suggest that nitric oxide may play a role in processing olfactory and photic information, circadian rhythms, and neuroendocrine regulation in tilapia.  相似文献   
5.
SUMMARY

Pistillate seedling plants of the local cultivar of papaya ‘Deshi’, transplanted 40 d after sowing, were sprayed with aqueous solutions of IBA (25 and 50 ppm), GA3 (100 and 200 ppm), kinetin (50 and 100 ppm), BA (25 and 50 ppm), ethephon (100 and 200 ppm) or with water (control) 100 d after transplanting, when the experimental fruits borne by them were 15 d old. Latex was collected from the fruits when they were 90-95 d old and continued on four occasions, at 7 d intervals. Highly significant increases in yield and in protease activity of the latex over the control was obtained by application of ethephon. IBA and GA, also increased latex production, but spraying the plants with kinetin or BA solutions gave no clear results  相似文献   
6.
In addition to its search for extrasolar planets, the NASA Kepler mission provides exquisite data on stellar oscillations. We report the detections of oscillations in 500 solar-type stars in the Kepler field of view, an ensemble that is large enough to allow statistical studies of intrinsic stellar properties (such as mass, radius, and age) and to test theories of stellar evolution. We find that the distribution of observed masses of these stars shows intriguing differences to predictions from models of synthetic stellar populations in the Galaxy.  相似文献   
7.
8.
Impacts of 43-year nutrient management on carbon (C) and nutrient dynamics were studied in a rice-wheat-jute system in tropical India. Carbon dynamics was investigated on the basis of its distribution of labile (microbial biomass C, permanganate oxidizable C and water soluble C) and slow pools (Walkley Black oxidizable organic C), its indices (C pool index, lability index) and C management index (CMI) at different soil depths. Nutrient dynamics was judged by major nutrients availability, and related soil enzymatic activities. We studied seven treatments including unfertilized control, 100% NPK (N:P2O5:K2O 60:30:60), 50% NPK, 150% NPK, 100% NP, 100% N, 100% NPK + farm yard manure (10 tonnes FYM ha?1). Nutrients availability and soil enzymatic activities were significantly increased under balanced fertilization (100% NPK + FYM) over other treatments. Labile, slow and total C was also found highest in 100% NPK + FYM. Enhanced C indices under 100% NPK + FYM over 100% NPK and other treatments signified the importance of long term balanced fertilization on soil C stabilization. Lability indexes were lower at sub-soil (30-45cm). In terms of favourable nutrient dynamics and CMI, balanced application of NPK plus organics were recommend for long term sustainability of rice-wheat-jute system in tropics.  相似文献   
9.
Climate change is likely to affect the persistence of large, space-requiring species through habitat shifts, loss, and fragmentation. Anthropogenic land and resource use changes related to climate change can also impact the survival of wildlife. Thus, climate change has to be integrated into biodiversity conservation plans. We developed a hybrid approach to climate-adaptive conservation landscape planning for snow leopards in the Himalayan Mountains. We first mapped current snow leopard habitat using a mechanistic approach that incorporated field-based data, and then combined it with a climate impact model using a correlative approach. For the latter, we used statistical methods to test hypotheses about climatic drivers of treeline in the Himalaya and its potential response to climate change under three IPCC greenhouse gas emissions scenarios. We then assessed how change in treeline might affect the distribution of snow leopard habitat. Results indicate that about 30% of snow leopard habitat in the Himalaya may be lost due to a shifting treeline and consequent shrinking of the alpine zone, mostly along the southern edge of the range and in river valleys. But, a considerable amount of snow leopard habitat and linkages are likely to remain resilient to climate change, and these should be secured. This is because, as the area of snow leopard habitat fragments and shrinks, threats such as livestock grazing, retaliatory killing, and medicinal plant collection can intensify. We propose this approach for landscape conservation planning for other species with extensive spatial requirements that can also be umbrella species for overall biodiversity.  相似文献   
10.
Forest fire is a major cause of changes in forest structure and function. Among various floristic regions, the northeast region of India suffers maximum from the fires due to age-old practice of shifting culti- vation and spread of fires from jhum fields. For proper mitigation and management, an early warning of forest fires through risk modeling is required. The study results demonstrate the potential use of remote sens- ing and Geographic Information System (GIS) in identifying forest fire prone areas in Manipur, southeastern part of Northeast India. Land use land cover (LULC), vegetation type, Digital elevation model (DEM), slope, aspect and proximity to roads and settlements, factors that influ- ence the behavior of fire, were used to model the forest fire risk zones. Each class of the layers was given weight according to their fire inducing capability and their sensitivity to fire. Weighted sum modeling and ISODATA clustering was used to classify the fire zones. To validate the results, Along Track Scanning Radiometer (ATSR), the historical fire hotspots data was used to check the occurrence points and modeled forest fire locations. The forest risk zone map has 55 63% of agreement with ATSR dataset.  相似文献   
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