Energy and carbon dioxide (CO2) balance of logging residues as alternative energy resources: system analysis based on the method of a life cycle inventory (LCI) analysis

Using the method of a life cycle inventory (LCI) analysis, the energy balance and the carbon dioxide (CO₂) emission of logging residues from Japanese conventional forestry as alternative energy resources were analyzed over the entire life cycle of the residues. The fuel consumption for forestry machines was measured in field experiments for harvesting and transporting logging residues at forestry operating sites in Japan. In addition, a total audit of energy consumption was undertaken. It involved an assessment of materials, construction, and the repair and maintenance of forestry machines as well as the costs associated with an energy-conversion plant. As a result, the ratio of energy output to input was calculated to be 5.69, indicating that the system examined in this study could be feasible as an energy production system. The CO₂ emission per MWh_e (e: electricity) of the biomass-fired power generation plant was calculated to be 61.8kgCO₂/MWh_e, while that of coal-fired power generation plants in Japan is 960kgCO₂/MWh_e. Therefore, the reduction in the amount of CO₂ emission that would result from replacing coal with biomass for power generation by as much as 3.0 million dry-t/year of logging residues in Japan was estimated to be 1.66 million tCO₂/year, corresponding to 0.142% of the national CO₂ emission. This study provides evidence that Japan could reduce its domestic CO₂ emission by using logging residues as alternative energy resources.     

Embryo collection from pigs post‐pseudopregnancy induced by estradiol dipropionate

We aimed to define whether embryo collection carried out after pseudopregnancy was of similar outcome and quality as after artificial abortion. To induce pseudopregnancy, 30 gilts or sows were given 20 mg intramuscular estradiol dipropionate (EDP) 10–11 days after the onset of estrus. Ten additional pigs were inseminated artificially at natural estrus as a control group. Prostaglandin F_2α (PGF_2α) was administered twice with a 24 hr interval beginning 15, 20, or 25 days after EDP‐treatment (n = 10 per group) or between 23 and 39 days after artificial insemination in control pigs. Following this, all pigs were given 1,000 IU equine chorionic gonadotropin and 500 IU human chorionic gonadotropin (hCG) and then inseminated. Embryos were recovered 6 or 7 days after hCG treatment and outcome was recorded. There was no significant difference in the number of normal embryos collected from the pigs with PGF_2α initiated at different time points or from the control group. Embryonic developmental stages 7 days after hCG treatment also did not differ among groups. These results indicate that the use of EDP to induce pseudopregnancy, followed by PGF_2α administration to synchronize estrus for subsequent embryo harvest, is a suitable alternative to the artificial abortion method.     

Comparative external morphology of cetacean spermatozoa

SUMMARY: To compare size and morphology of spermatozoa in cetaceans, sperm and epididymis samples were collected from 10 species in four families and spermatozoa were observed with phase-contrast and scanning electron microscopes. According to the average total length of the spermatozoa, the 10 species examined were classified into the following four groups in order of increasing size: (i) Baird's beaked (Ziphiidae) and Bryde's whales (Balaenopteridae); (ii) Dall's and finless porpoises (Phocoenidae); (iii) common, bottlenose, and Pacific white-sided dolphins (Delphinidae); and (iv) killer and short-finned pilot whales, and Risso's dolphin (Delphinidae). Spermatozoa head length of Bryde's whale and the finless porpoise were shorter than those of the other species. Spermatozoa head width was widest in the killer whale and thinnest in the Baird's beaked whale. The lateral aspects of sperm heads from the 10 species were characterized as the 'anterior region of the sperm head is thin and flat while the posterior region is thick.' The dorsal aspects of sperm heads were 'paddle-shaped' in Bryde's whales, 'bowling pin-shaped' in Baird's beaked whales, 'Japanese fan-shaped' in killer whales, an 'elongated ellipsoid shape' in Delphinidae except for killer whales, and 'ellipsoid shaped' in Phocoenidae. Size and morphology of the spermatozoa showed interspecific differences among the 10 species examined, which correspond to cetacean taxonomic classification.     

Morphological relationship between intercalated duct and pancreatic islet in streptozotocin and/or camostat mesilate administrations in the chicken

Present electron microscopical and immunocytochemistrical studies elucidated some morphological relationship between intercalated duct (ICD) and pancreatic islet cells in the chicken in streptozotocin (STZ) and/or camostat mesilate (CM) administrations. Twenty-one chickens were set into four experimental groups: (1) control group, (2) STZ administration group, (3) CM administration group, and (4) STZ + CM administration group. Cytoplasms of ICD cells stained more strongly with eosin in STZ administration group than other groups, and electron-dense materials and intercalated processes between ICD and islet cells were also increasing in time dependence in STZ administration. Number of pancreatic islet in STZ + CM co-administration was about 3.1 times larger than other groups. Many small sized cells were detected at surrounding area of ICD and they incorporated 5-bromo-2'-deoxyuridine better than other experimental groups. Present morphological data suggested that ICD cells might support some tolerances of pancreatic endocrine cells against toxic substances and also involve in regeneration of new pancreatic islet cells in STZ + CM co-administration.     

Expression of nestin and IGF-1 in rat pancreas after streptozotocin administration

The present study examines whether centroacinar (CA) and intercalated duct (ICD) cells can serve as stem cells, after administration of the diabetogenic agent streptozotocin (STZ). Thirty rats were divided into five experimental groups: (1) control, (2) 1 day after STZ (STZ-1), (3) 3 days after STZ (STZ-3), (4) 7 days after STZ (STZ-7) and (5) 14 days after STZ (STZ-14). Many small pancreatic islets were observed in the STZ-7 group than in the other experimental groups, and many of these small islets were in close contact with ICD and CA cells. A higher number of nestin, insulin-like growth factor-1 (IGF-1) and IGF-1-receptor positive ICD and CA cells were observed at STZ-3 and STZ-7 than at the others. These expression patterns coincided well with the proliferating cell nuclear antigen pattern. The results suggest that rat pancreatic endocrine cells after damage by STZ administration might be recovered from newly generated cells derived from ICD and CA cells.