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101.
The productivity and chipping cost of a low-investment small mobile chipper were investigated. The effect of capital cost on chipping cost reduction was analyzed by changing the service life of the chipper when assuming a target operational chipping cost set at 250 yen m?3. Productivity of the investigated chipper was found to be at 23.7 m3 h?1 in chip volume with fuel consumption at 14.6 L h?1. The results showed that the chipping cost of the investigated chipper was lower than that of a higher priced and more productive grinder. Neither chipper nor grinder, however, could achieve the assumed target cost of 250 yen m?3 even if their service lives were extended. It was necessary to withstand the initial grapple loader and the labor costs or raise the grinder’s productivity to 33 m3 h?1 in order to reach a comparable operational cost target with that of the investigated chipper. Similarly, the grinder would have to reduce its capital cost and fuel consumption to maintain the chipping cost of 250 yen m?3 ifproductivity could not be improved. Net chipping cost of the investigated chipper was relatively small compared to that of the tub grinder, especially under a shorter service lifespan. The investigation shows that it is feasible for small-scale forestry to introduce a low-investment mobile chipper because it does not require a large amount of material and has a low chipping cost. Moreover, lowering the capital cost or the price of chippers is a more realistic cost savings in the long term.  相似文献   
102.
A subcutaneous mass in the right femoral region of a female F344 Slc/N rat was examined histopathologically. At 83 weeks of age, the animal showed symptoms of severe anemia and nasal bleeding. Necropsy revealed that the mass had invaded the skeletal muscles but did not affect the bones. Multicentric nodules were also observed in the lung. Histopathology revealed a sheet-like growth pattern of polygonal tumor cells with round or comma-shaped nuclei and pale eosinophilic cytoplasm. Osteoid tissue was observed in not only the original lesion but also the metastatic foci in the lung. Each tumor cell was surrounded by argentophil fibers and few collagen fibers. Immunohistochemically, the tumor cells were positive for proliferating cell nuclear antigen (PCNA), vimentin, osterix and osteocalcin, but negative for keratin, S-100, von Willebrand factor, CD-31, CD-34, desmin, α-smooth muscle actin, lysozyme, α1-antitrypsin and rat malignant fibrous histiocytoma (MFH) antigen. CD-68-positive cells were considered to be infiltrated macrophages because they were negative for PCNA. On the basis of these findings, we diagnosed the present case as extraskeletal osteosarcoma.  相似文献   
103.
Adenosine triphosphate (ATP) hydrolysis in the nitrogenase complex controls the cycle of association and dissociation between the electron donor adenosine triphosphatase (ATPase) (Fe-protein) and its target catalytic protein (MoFe-protein), driving the reduction of dinitrogen into ammonia. Crystal structures in different nucleotide states have been determined that identify conformational changes in the nitrogenase complex during ATP turnover. These structures reveal distinct and mutually exclusive interaction sites on the MoFe-protein surface that are selectively populated, depending on the Fe-protein nucleotide state. A consequence of these different docking geometries is that the distance between redox cofactors, a critical determinant of the intermolecular electron transfer rate, is coupled to the nucleotide state. More generally, stabilization of distinct docking geometries by different nucleotide states, as seen for nitrogenase, could enable nucleotide hydrolysis to drive the relative motion of protein partners in molecular motors and other systems.  相似文献   
104.
Metastin/kisspeptin, the KiSS-1 gene product, has been identified as an endogenous ligand of GPR54 that reportedly regulates GnRH/LH surges and estrous cyclicity in female rats. The aim of the present study was to determine if metastin/kisspeptin neurons are a target of estrogen positive feedback to induce GnRH/LH surges. We demonstrated that preoptic area (POA) infusion of the anti-rat metastin/kisspeptin monoclonal antibody blocked the estrogen-induced LH surge, indicating that endogenous metastin/kisspeptin released around the POA mediates the estrogen positive feedback effect on GnRH/LH release. Metastin/kisspeptin neurons in the anteroventral periventricular nucleus (AVPV) may be responsible for mediating the feedback effect because the percentage of c-Fos-expressing KiSS-1 mRNA-positive cells to total KiSS-1 mRNA-positive cells was significantly higher in the afternoon than in the morning in the anteroventral periventricular nucleus (AVPV) of high estradiol (E(2))-treated females. The percentage of c-Fos-expressing metastin/kisspeptin neurons was not different between the afternoon and morning in the arcuate nucleus (ARC). Most of the KiSS-1 mRNA expressing cells contain ERalpha immunoreactivity in the AVPV and ARC. In addition, AVPV KiSS-1 mRNA expressions were highest in the proestrous afternoon and lowest in the diestrus 1 in females and were increased by estrogen treatment in ovariectomized animals. On the other hand, the ARC KiSS-1 mRNA expressions were highest at diestrus 2 and lowest at proestrous afternoon and were increased by ovariectomy and decreased by high estrogen treatment. Males lacking the surge mode of GnRH/LH release showed no obvious cluster of metastin/kisspeptin-immunoreactive neurons in the AVPV when compared with high E(2)-treated females, which showed a much greater density of these neurons. Taken together, the present study demonstrates that the AVPV metastin/kisspeptin neurons are a target of estrogen positive feedback to induce GnRH/LH surges in female rats.  相似文献   
105.
This study aimed to evaluate radial and among-family variations of wood properties in Picea jezoensis. A total of 174 trees were randomly selected from 10 open-pollinated families in a progeny trial for measuring stem diameter, dynamic Young’s modulus of log (DMOElog), annual ring width (ARW), air-dry density (AD), modulus of elasticity (MOE), and modulus of rupture (MOR). Mean values of DMOElog, AD, MOE, and MOR were 9.60 GPa, 0.41 g/cm3, 9.44 GPa, and 76.6 MPa, respectively. Significant differences among families were observed in all properties. F values obtained by analyzing variance in wood properties were higher than those generally observed in growth traits. In addition, F values in wood properties remained relatively higher from the 1st to 25th annual ring from the pith, although F value in ARW rapidly decreased with each increase in annual ring number. These results indicate that genetic factors largely contributed to the variance in wood properties compared with the growth traits.  相似文献   
106.
Using analogies from soil science a new global radiation estimation method was developed and tested on a large North-American meteorological database. The newly developed procedure was compared to the well-known, Donatelli-Campbell method. Both the overall indicators and the more detailed analysis of the model performance confirmed that the new method is more efficient than the Donatelli-Campbell method. The improved performance is due to the greater number of parameters, as well as to the more adequate function type it uses during the calculation. Results suggest that it is sufficient to have 2 year-long data series for parameterizing the new method to provide at least as accurate radiation estimates as provided by the Donatelli-Campbell method. The new method can be efficiently used for locations with no radiation measurement by combining it with a simple spatial interpolation technique.  相似文献   
107.
The inverse of the relative increment rate of size is proposed as a measure of the maturity of a forest tree. The heartwood content within bole cross sections is modeled semiempirically using asymptotic fitting. It is shown that the present proposal for a definition of maturity statistically explains heartwood content far better than age or size. The heartwood content appears to be independent on growth rate and tree size.  相似文献   
108.
109.
The application of low-level direct electric current (0.15 mA cm?2) as an electrokinetic technique to treat copper-contaminated mesophilic anaerobic granular sludge was investigated. The sludge was obtained from a full scale UASB reactor treating paper-mill wastewater and was artificially contaminated by Cu(NO3)2 or CuEDTA2? with initial copper concentrations of 1000 mg . kg?1 wet sludge. The effect of different electrokinetic cell layouts, pH and EDTA concentrations on the migration of copper and iron during electrokinetic treatment were evaluated. Both, the pH of the sludge cake or the copper complexation with EDTA significantly affected the migration direction of copper. In an ‘open’ cell (sludge cake in direct contact with air), the highest copper mobility was observed at pH 2.5 in both Cu(NO3)2 or CuEDTA2? amended sludge. The highest copper accumulation was at the cathode (22 ± 2)% with CuEDTA2? as contaminant. In a ‘closed’ cell (sludge cake not in contact with air), the highest accumulation was obtained for CuEDTA2? at the anode and amounted to 4(± 0.5)% and 2(± 0.05)%, respectively, at a final pH of 4.2 and 7.7 in the sludge cake.  相似文献   
110.
Anticoccidial drugs are extensively used in the poultry industry to control the infection of the single-cell protozoa of the genus Eimeria. The most commonly used coccidiostats in poultry are the polyether ionophores such as narasin and salinomycin. This paper presents a rapid and simple method for the screening of residues of these two coccidiostatic compounds in poultry and eggs. The method is based on time-resolved fluoroimmunoassay. Sample preparation of eggs consists only of one extraction and evaporation step, and a solid phase extraction step is needed only for the muscle sample preparation. Mean recoveries were 91.0% from muscle tissue and 81.1% from eggs for both narasin and salinomycin. The performance of the assay was evaluated only for narasin because salinomycin had a cross-reactivity of 100% in the assay, and the recoveries of the compounds were not significantly different (P >0.05). The limits of detection [mean + 3 x standard deviation (SD)] of narasin were 0.56 and 0.28 microg/kg, and the limits of quantification (mean + 9 x SD) were 1.80 and 0.57 microg/kg for muscle and eggs, respectively. The coefficients of variation (CV) of the interassay precision of the method, evaluated by five replicate analyses of muscle samples spiked with 2 microg/kg of narasin and egg samples spiked with 1 microg/kg of narasin, were 4.1 and 6.4%, respectively. The CVs of intra-assay precision tests, determined by 10 replicate analyses at the above-mentioned concentration levels, were 3.8 and 4.5%, respectively.  相似文献   
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