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121.
Immunohistochemical localization of endothelial and inducible nitric oxide synthase within neurons of cattle with rabies 总被引:1,自引:0,他引:1
Shin T Weinstock D Castro MD Hamir AN Wampler T Walter M Kim HY Acland H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(5):539-541
The expression of constitutive endothelial nitric oxide synthase (eNOS) and inducible NOS (iNOS) in the brains of cattle with natural rabies was studied. Increased expression of eNOS was detected in neurons of the brain stem and Purkinje cells of cerebellum. By contrast, iNOS was diffusely localized in the cytoplasm of affected neurons, and some inflammatory cells were positive. eNOS and rabies antigen were co-localized in inclusion bodies (Negri bodies) in neurons. The specific localization of eNOS, but not iNOS, in the Negri bodies suggests that eNOS is involved in the formation of rabies virus inclusion bodies. 相似文献
122.
123.
Summary Water application pattern, WAP, is one of the most important factors that determine the instantaneous and the cumulative application rates of moving irrigation machines. The mathematical background of a procedure to predict and design the WAP of moving irrigation machines is introduced. It includes a mathematical analysis of the effect of pressure head, height and spacing between emitters on the WAP, and a nomograph that presents this analysis graphically and illustrates the design procedure of the application pattern of irrigation machines.Abbreviations
P()a
water application rate at a normalized radial distance from the emitter [m/s]
-
ka
number of linear segments needed to represent the pattern
- s/Ra
normalized radial distance from the emitter
-
Ra
wetted radius [m]
-
sa
radial distance from the emitter [m]
-
n
j n
i/ha
normalized water application rate at point
-
j, ha
maximum water application rate [m/s] n
j water application rate at point j [m/s]
-
j
=m
j/Ra
normalized radial distance of point j from emitter
-
m
ja
radial distance of point
-
ja
from emitter [m], CWAP
- (x)a
Cumulative Water Application Pattern: amount of water per unit area applied at a distance
-
xa
from the travel path of the emitter [m3/m2]
-
xa
distance from the travel path of the emitter [m]
-
T
xa
time of application at a distance
-
xa
from the travel path of the emitter [s]
-
va
velocity of propagation of the machine [m/s]
-
k
1a
the outmost linear segment that its radial distance from the emitter
-
m
k1a
is smaller than the distance of the travel path from the emitter
-
x, T
ja
time at which the
-
j
tha
linear segment (ring) stops influencing the point located at a distance
-
xa
from the emitter
-
1,
2,
3a
dimensionless numbers derived by dimensional analysis
-
ua
water jet velocity [m/s]
-
ga
gravity acceleration [m/s2]
-
da
nozzle diameter [m], v kinematic viscosity [m2/s]
-
Ha
emitters height [m]
-
, a
regression analysis coefficients
-
Paa
Pattern fit coefficient for water application
-
F(r)a
normalized desired water application pattern [1/m]
-
f(r)a
normalized actual water application pattern [1/m]
-
La
common distance on which
-
F(r) and f(r)a
are defined [m], SP spacing interval between emitters [m]
-
DSa
dimensionless spacing interval between emitters
-
DSa
variation of dimensionless spacing interval
-
Paa
variation of Pa coefficient
-
Pa
pressure head [kPa] 相似文献
124.
This paper deals with the problem of modelling sub-county areas that are so small that county level forecasts cannot be used for policy purposes. Starting from a simple specification that relates demand for local goods and services to local and non-local income, a system of equations is developed that can be used as a satellite to a county model to forecast impacts of economic events at the town level. Regression coefficients for the equations are estimated using data at the one-digit SIC code level for a pooled sample of towns in Massachusetts. Model validation tests are reported. An example of an application is provided by simulating impacts of 500 new manufacturing jobs in a town within a county. Our approach yields simulation and forecasting results for both the town and the county. 相似文献
125.
126.
127.
128.
种植小麦的土壤中微生物生物量的动态变化 总被引:1,自引:0,他引:1
A controlled release N fertilizer was developed by the carrier method using natural polysaccharides (PS) and urea. The results showed that mixing of PS and urea led to significant control of urea release. When a cross-linker (boric acid or glutaraldehyde) was added, a better control effect was observed. During a 30 min leaching time the nitrogen release rate from the controlled release fertilizer was nearly constant, which was significantly different from normal urea. One of the controlled release mechanisms was related to space resistance from a large molecular structure. Infrared (IR) analysis indicated that interaction of PS with urea was through a hydrogen bond or a covalent bond. These bonds created an a-helix or high molecular network fertilizer carrier system, which was another reason for a controlled nutrient release. Pot experiment showed that nitrogen use efficiency could increase significantly with a carrier fertilizer. 相似文献
129.
130.
巴基斯坦白沙瓦市铅和镉在不同路旁土壤及植物中的污染 总被引:1,自引:0,他引:1
Soil and plant samples were collected from roadside sites (along with primary, secondary and tertiary roads) and reference site to investigate the contamination of soils and old common plant species with lead (Pb) and cadmium (Cd) in Peshawar City, Pakistan. All the data were analyzed using ANOVA analysis that showed a significant (P ≤ 0.01) variation in Pb and Cd concentrations in the roadside soils and plants as compared to the reference site. The mean concentrations of Pb and Cd were 53.9 and 6.0 mg kg-1 in soils and 49.1 and 10.9 mg kg-1 in plants, respectively. Significant variation (P ≤ 0.01) in concentrations of Pb and Cd in soil and plant samples along with primary, secondary and tertiary roads might be due to different traffic densities. The highest value (9.4) of metal accumulation index (MAI) was observed for Eucalyptus camaldulensis. In selected plant species, the Pb and Cd accumulation was found in the order of E. camaldulensis > Ficus elastica > Dalbergia sissoo > Alstonia scholaris. The roadside soils and plants were highly contaminated with Pb and Cd as compared to the reference site. 相似文献