拖拉机驾驶员作业强度对其生理负荷的影响（简报）

驾驶拖拉机作业时,驾驶员的作业强度与生理负荷随着拖拉机的转向机构的不同而有较大的差别。该研究基于拖拉机两种不同的转向机构,对被测试人员实际作业时的心率和氧气的消耗量等指标进行测试,获得了不同的转向机构下被测试人员的心理和生理的变化规律。结果表明,被测人员随着不同转向机构其作业的强度也发生了变化。试验结果为设计新型的拖拉机的各系统提供了驾驶人员自身的数据,同时为改进现有的拖拉机的各系统提供重要的理论参考。     

拖拉机驾驶员作业强度对其生理负荷的影响

驾驶拖拉机作业时,驾驶员的作业强度与生理负荷随着拖拉机的转向机构的不同而有较大的差别.该研究基于拖拉机两种不同的转向机构,对被测试人员实际作业时的心率和氧气的消耗量等指标进行测试,获得了不同的转向机构下被测试人员的心理和生理的变化规律.结果表明,被测人员随着不同转向机构其作业的强度也发生了变化.试验结果为设计新型的拖拉机的各系统提供了驾驶人员自身的数据,同时为改进现有的拖拉机的各系统提供重要的理论参考.     

Application of the coastal ecosystem complex concept toward integrated management for sustainable coastal fisheries under oligotrophication

Harmonizing coastal fisheries with water-quality improvement has become an essential factor for the sustainable use of coastal ecosystem services. Here, we present the scope of our study based on an interdisciplinary approach including ecological actions, socio-economic actions and socio-psychological actions. We chose to focus on the interaction between oyster aquaculture and seagrass vegetation as a typical ecological action using the coastal ecosystem complex (CEC) concept. Coastal organisms have adapted their traits to the environment over a long period of time, so that restoration of the CEC represents reconstruction of the original process of coastal production. Subtidal seagrass vegetation with intertidal oyster reefs is the original CEC in Japan, which would be expected to enhance coastal production by improving the production efficiency without adding nutrients. A simple field experiment examining carbon and nitrogen contents and stable isotope ratios revealed that oyster spats cultivated on a tidal flat adjacent to seagrass beds had higher nitrogen contents and higher δ¹³C ratios than spats cultivated in an offshore area using only pelagic production. This result suggests that utilization of the CEC, which enables oysters to use both pelagic and benthic production, has potential to sustain a food provisioning service for humans, even in oligotrophic conditions.     

An angiotensin converting enzyme inhibitor,benazepril can be transformed to an active metabolite,benazeprilat, by the liver of dogs with ascitic pulmonary heartworm disease

To examine whether an angiotensin converting enzyme (ACE) inhibitor, benazepril, can be transformed to the active metabolite, benazeprilat, by severely injured liver of dogs with ascitic heartworm disease, benazepril hydrochloride was administered orally to dogs once daily for 7 consecutive days at a dose rate of 0.29 mg/kg to 0.63 mg/kg of body weight, and plasma benazepril and benazeprilat concentrations were determined on the 1st and 7th administration days. In 7 dogs with ascitic pulmonary heartworm disease, plasma benazeprilat concentrations tended to be higher than in 7 control dogs both on the 1st and 7th administration days. The peak concentration and area under the concentration-time curve tended to be greater in dogs of the ascites group than in control dogs, but the statistics could not detect significant differences in the time to peak concentration and t(1/2) between the control and ascites groups. Plasma ACE activities decreased after administration of benazepril. In dogs with ascitic heartworm disease, benazepril was readily transformed to benazeprilat by the liver, and was effective for suppression of plasma ACE activity.     

Phagocytosis of bovine blood and milk polymorphonuclear leukocytes after ozone gas administration in vitro

To determine the effects of ozone on the phagocytosis of bovine polymorphonuclear leukocytes (PMNs), ozone gas was administered in vitro on the blood and milk of healthy lactating cows, cows with acute mastitis, and cows with milk fever. In the blood of healthy dairy cattle, although there was no significant effect of ozone gas on the viability of the leukocytes, phagocytosis of PMNs significantly decreased. In contrast, ozone gas administration in vitro significantly increased phagocytosis of PMNs from the blood of cows with acute mastitis and milk fever, and from mastitic milk. These findings showed that ozone administration in vitro has positive and negative effects on bovine PMN phagocytosis, depending on the health status of the animal.     

Uptake and translocation of bleaching herbicidal compounds in radish seedlings

The relationship between the hydrophobicity of certain herbicidal compounds and the bleaching pattern caused on radish cotyledons was investigated. Seed treatment with diphenylpyridones, as well as with established herbicides, produced three types of bleaching pattern according to their hydrophobicity. The less hydrophobic compounds caused complete bleaching of both cotyledons, but the compounds with more hydrophobicity caused only partial bleaching. The critical points for whole or partial bleaching were in the range of log K_ow 4–5 (K_ow: octanol/water partition coefficient), and these values were changed slightly with their chemical classes. Uptake of compounds into the seed coat took place rapidly; these compounds were then translocated slowly from the seed coat to the embryo, namely, radicle, abaxial surface of one cotyledon and marginal areas of both cotyledons. Application of these compounds to roots resulted in initial translocation to marginal areas of both cotyledons, with subsequent translocation to the middle area. It is believed that compounds taken up into the radicle were translocated to both cotyledons in a manner similar to that following application to roots. These effects following uptake by seeds can be used as a translaminal and lateral transport assay for bleaching herbicidal compounds in cotyledons.     

Determination of lignin,holocellulose, and organic solvent extractives in fresh leaf,litterfall, and organic material on forest floor using near-infrared reflectance spectroscopy

We report the results of a study regarding the near-infrared reflectance spectra of various leaf stages from fresh to senescing, and to decomposing leaf. A broad absorbance feature increased in the region of 1100–1400nm with the advance of the leaf senescence and leaf decomposition. A decrease was seen in the region over 1440nm during the senescence and decomposition process. These differences of spectra showed the changes in constituents of leaf in terms of the degree of the senescence and decomposition. A comparison of multiple linear regression between the near-infrared reflectance spectra and proximate chemical analyses showed that near-infrared reflectance spectroscopy achieved a certain level of useful accuracy. We consider that near-infrared reflectance spectroscopy has the potential to predict the contents of carbon fractions in plant materials, and that this method can replace previous methods due to faster determination of carbon fractions, and its ability to significantly increase the number of samples that can be collected and measured.     

Soil respiration and soil CO<Subscript>2</Subscript> concentration in a tropical forest,Thailand

Soil respiration and soil carbon dioxide (CO₂) concentration were investigated in a tropical monsoon forest in northern Thailand, from 1998 to 2000. Soil respiration was relatively high during the rainy season and low during the dry season, although interannual fluctuations were large. Soil moisture was widely different between the dry and wet seasons, while soil temperature changed little throughout the year. As a result, the rate of soil respiration is determined predominantly by soil moisture, not by soil temperature. The roughly estimated annual soil respiration rate was 2560gCm^–2year^–1. The soil CO₂ concentration also increased in the rainy season and decreased in the dry season, and showed clearer seasonality than soil respiration did.     

Decreases in serum apolipoprotein C-III concentration in cows with ethionine-induced fatty liver

To monitor the serum concentration of apolipoprotein C-III (apoC-III), one of the functional apoproteins in lipid metabolism, in cows with ethionine-induced fatty liver, and to investigate the association of apoC-III with liver triglyceride (TG) content and serum biochemical variables, seven nonpregnant nonlactating Holstein cows (3 to 6 years old) were used. Five cows were treated with ethionine, an analogue of methionine, (days 0, 7 and 14). The remaining two controls received saline as the vehicle. Liver TG contents in the treated cows were increased markedly whenever administered, and significant increases were observed at days 14 (666.4%, 85.3 mg/g) and 21 (675.0%, 86.4 mg/g) compared with day 0. In controls, no significant changes in liver TG content and serum biochemical variables were observed during this experiment. The serum apoC-III concentration in the treated cows was decreased drastically after the first administration and fell to the lowest value at day 10 (76.2 microg/ml, 32% of day 0). The apoC-III was significantly (p<0.05) correlated with non-esterified fatty acids (r= -0.526), gamma-glutamyl transpeptidase (r= -0.407), total bilirubin (r= -0.464), positively with apolipoprotein B-100 (apoB-100, r=0.601) and cholesterol ester (r=0.449). Although apoB-100 concentrations were also reduced by the administrations, the concentrations tended to recover smoothly toward the next administration. The distinct difference in change between apoC-III and apoB-100 suggests that apoC-III may be regulated by other pathways, in addition to inhibiting the synthesis of apoproteins by ethionine.     

Breeding season in female cats acclimated under a natural photoperiod and interval until puberty

The breeding season was investigated in 174 female cats that were acclimated under a natural photoperiod, and determined the interval between birth and initial estrus (puberty) was determined in 125 cats. Although the breeding season differed noticeably among individual animals, the mean was 180.4 +/- 3.0 (SE) days between the end of January and the end of July. The interval between birth and first estrus ranged from 181 to 560 days, with a mean of 345.0 +/- 0.9 days. With respect to month of birth, the mean interval was 343.0 +/- 9.5 days in cats born between March and June. Among cats that were born between July and October, the mean intervals were 242.0 +/- 6.3 days in cats that exhibited estrus the year after birth and 519.2 +/- 5.8 days in those that exhibited estrus 2 years after birth.