Relationship between cation-exchange capacity and degree of maturity of city refuse composts

Abstract

An attempt was made to estimate the degree of maturity of city refuse composts by measuring their cation-exchange capacity (CEC).

The CEC of the city refuse compost increased for the first 7 days after commencement of the fermentation process, decreased for the next 2 days, and then increased again gradually up to the end of the piling period.

A highly significant negative correlation was noted between the CEC and C/N ratio of the city refuse composts (r=-0.903***). Regression analysis yielded the relationship: In CEC=7.02-1.02 In C/N

The CEC values of the city refuse composts, which were considered to have been sufficiently matured for application, were greater than about 60 me/ 100 g of ash-free material.     

Factors Influencing the Determination of Microbial Biomass-Nitrogen in Submerged Soil

In a previous paper (1), a modification of the chloroform fumigation method (2) was proposed for estimating microbial biomass-nitrogen (N) in submerged soil. It was found that a large part of the living bacteria in the submerged soil was killed within about 12 h of the fumigation and was actively mineralized by subsequent anaerobic incubation.

In this paper, the following factors which influence the estimated amount of microbial biomass-N were examined: a) inoculation to fumigated soil, b) duration of anaerobic incubation, c) storage and sieving pretreatments of soil, and d) effect of fumigation on soil organic matter.     

A new method for nondestructive evaluation of solid wood moisture content based on dual-energy X-ray absorptiometry

This paper presents a new method to determine the moisture content of solid wood based on the principle of dual-energy X-ray absorptiometry. The study investigates the theoretical relationship between X-ray wavelength and mass attenuation coefficients of wood, water, and reference substance. In accordance with this relationship, a theoretically obtained equation is proposed to calculate the moisture content in wood. The proposed equation is compared to experimental results using small blocks of sugi wood, which showed that the change in mass attenuation coefficient of wood with X-ray tube voltage increased with increasing moisture content as expected from the theoretical equation. A regression equation for moisture content estimation was determined based on the experimental results, and the standard error of estimate in the 0–120 % dry-basis moisture content range using the regression equation was determined to be 21.9 % with the most appropriate pair of tube voltages, 15 and 40 kVp. The accuracy of the method will be improved by reducing the duration of X-ray radiography and by increasing the disparity between paired tube voltages. This method has the potential to determine moisture content of solid wood using X-ray without oven-drying or assuming oven-dry density.     

Change of antibody levels to ferritin in the sera of foals after birth: Possible passive transfer of maternal anti‐ferritin autoantibody via colostrum and age‐related anti‐ferritin autoantibody production

Antibody (immunoglobulin G (IgG), IgM or IgA) levels relative to ferritin in six foal sera (three male and three female) after birth (day 0 and 2, 6, 10, 20, 28, 36, 40, 52 and 56 weeks of age) were semi‐quantitatively measured with normalization with antibody activity to ferritin in one adult horse serum. After addition of horse spleen ferritin to the serum sample, the complex formed between antibodies to ferritin in the serum and ferritin was co‐immunoprecipitated using antibody to horse spleen ferritin. Antibody classes of the co‐immnoprecipitate were detected with antibodies specific for horse IgG, IgM or IgA heavy chain. Six adult horse serum samples were found to have ferritin‐binding activities in all immunoglobulin classes examined. Although ferritin antibody activities (IgG, IgM and IgA) were scant in the foal sera before sucking colostrum (day 0), their activities increased at 2 weeks of age. IgG antibodies showed a biphasic response and IgM antibody activity increased up to 40 weeks of age. Antibody (IgG, IgM and IgA) activities to ferritin in three colostrum samples were significantly higher than in adult horse serum samples. These results demonstrate that antibody to ferritin in foal serum is derived from colostrum after birth and is produced thereafter.     

Genetic population structure of the Pacific bluefin tuna Thunnus orientalis and the yellowfin tuna Thunnus albacares in the North Pacific Ocean

The genetic population structure of the Pacific bluefin tuna (PBF) Thunnus orientalis and the yellowfin tuna (YFT) T. albacares in the North Pacific Ocean was investigated. The polymorphism of microsatellite (SSR) loci and sequences of mitochondrial DNA control region (mtCR) were analyzed for 71 samples of PBF from Japan and Mexico and 45 samples of YFT from Japan and Panama. In the SSR analyses, both single-locus (?0.010 to 0.008 in PBF and ?0.023 to 0.020 in YFT) and global multilocus (0.003 in PBF and ?0.002 in YFT) F _ST values among the geographic populations were low and not significant in these species. In the mtCR analyses, neither the neighbor-joining tree nor the minimum spanning network showed genetic differentiation among the geographic populations in each species. The pairwise F _ST values among the geographic populations of them (?0.005 in PBF and ?0.020 to ?0.014 in YFT) were low and not significant. Our SSR and mtCR data suggested that genetic differentiations were not evident among the eastern and western populations in the North Pacific Ocean either in PBF or in YFT. Mismatch distributions, demographic parameters, and neutrality tests suggested that sudden population expansion of PBF and YFT in the North Pacific Ocean occurred 628,000–731,000 and 450,000–525,000 years ago, respectively.     

Genetic analysis of ion-beam induced extremely late heading mutants in rice

Two extremely late heading mutants were induced by ion beam irradiation in rice cultivar ‘Taichung 65’: KGM26 and KGM27. The F₂ populations from the cross between the two mutants and Taichung 65 showed clear 3 early: 1 late segregation, suggesting control of late heading by a recessive gene. The genes identified in KGM26 and KGM27 were respectively designated as FLT1 and FLT2. The two genes were mapped using the crosses between the two mutants and an Indica cultivar ‘Kasalath’. FLT1 was located on the distal end of the short arm of chromosome 8. FLT2 was located around the centromere of chromosome 9. FLT1 might share the same locus as EHD3 because their chromosomal location is overlapping. FLT2 is inferred to be a new gene because no gene with a comparable effect to that of this gene was mapped near the centromere of chromosome 9. In crosses with Kasalath, homozygotes of late heading mutant genes showed a large variation of days to heading, suggesting that other genes affected late heading mutant genes.     

Effect of wood species on thermal flow behavior and physical properties of thermoplastic moldings

The thermoplastic flow behavior of cedar flour steamed at different temperatures in the range of 160–220°C was measured using a rheometer and compared with that of beech flour. The temperature at which the cedar flour starts to flow was approximately 70°C higher than that of beech flour, and the cedar flour exhibited low flowability. Furthermore, thermoplastic moldings were prepared from cedar and beech flours, and their physical properties were examined. Similar to the case of beech, a resin-like molding with a density of approximately 1.45?g/cm³ was obtained from the cedar flour steamed at 180°C or higher, and it was revealed by SEM observation that in these moldings wood flour particles adhere to each other. The specific bending strength was maximum for the moldings obtained from 180°C-steamed flour for both types of wood.     

Successful blastocyst production by intracytoplasmic injection of sperm after in vitro maturation of follicular oocytes obtained from immature female squirrel monkeys (Saimiri boliviensis)

Advanced reproductive technologies are being applied for the propagation of squirrel monkeys, to ensure their preservation as a genetic resource and the effective use of their gametes in the future. In the present study, oocytes and spermatozoa were collected from live squirrel monkeys, following which piezo intracytoplasmic sperm injection (ICSI) was performed using these gametes. Follicular development was induced by administering equine chorionic gonadotropin (eCG) containing inhibin antiserum to an immature squirrel monkey female. The unilateral ovary was excised after the administration of human chorionic gonadotropin (hCG), to induce ovulation, following which the larger developed follicular oocytes were collected. Follicular oocytes were prepared for ICSI using sperm from the epididymal tail of a unilateral testis extracted from a mature male. The embryos were continuously incubated in CMRL 1066 medium supplemented with 10% (v/v) fetal bovine serum. Embryo culture was performed with cumulus cells. Two experiments of ICSI carried out with three females resulted in 14 mature oocytes from the 49 cumulus-oocyte complexes collected and five embryos, three of which developed into blastocysts. These blastocysts were vitrified, thawed, and transferred to recipient monkeys, but no pregnancies resulted. In conclusion, the present study is the first to successfully produce ICSI-derived blastocysts from MII oocytes obtained by means of hormone administration (a combination of eCG+inhibin antiserum and hCG) and in vitro maturation in immature squirrel monkeys.     

Effect of decay on shear performance of dowel-type timber joints

Monotonic and reversed cyclic loading tests were conducted on dowel-type timber joints with varying degrees of wood decay due to Fomitopsis palustris (Berk. et Curt.), a brown rot fungus, and the effect of decay on various shear performances of dowel-type joints was investigated. For joints affected by the brown rot fungus, the initial stiffness, yield load, and maximum load of dowel-type joints were significantly decreased, even with a small mass loss of wood. The reductions in shear performance were the largest for initial stiffness, followed by yield load and maximum load, in that order. For a 1% reduction of the yield load, initial stiffness and maximum load showed reductions of 1.15% and 0.77%, respectively. When dowel-type joints that had been exposed to the brown rot fungus were subjected to reversed cyclic loading, the gap between the dowel and the lead hole of the wood was increased and equivalent viscous damping was decreased. These results indicate that decay around the dowel lead hole especially affects the load-displacement behavior at small displacement level, and dowel-type joints under cyclic loading have very low resistance to forces acting on the wooden structure. Part of this report was presented at the 5th Symposium on Timber Bridges of the Japan Society of Civil Engineers, Tokyo, July 2006; the 56th Annual Meeting of the Japan Wood Research Society, Akita, August 2006; and the Annual Meeting of the Architectural Institute of Japan, Fukuoka, August 2007     

Effect of chickpea husk dietary supplementation on blood and cecal parameters in rats

Chickpea husk was functionally evaluated for antioxidant status, blood parameters, cecal fermentation and microbial profiles in rats. Fifteen male rats (5 weeks of age) were divided into three groups; they were individually housed and fed one of the following diets for 3 weeks: purified diet containing 5% cellulose (Cellulose), an identical diet in which cellulose was replaced by corn starch (Starch) or by chickpea husk (Chick). Rats were sacrificed to obtain blood and cecal digesta samples. Chickpea husk contained high polyphenolic content and significant superoxide dismutase and 2,2‐diphenyl‐picrylhydrazyl scavenging activities. In a feeding experiment, Chick showed lowered cholesterol levels and improved antioxidant activity represented by reduced thiobarbituric acid reactive substances in blood. Chick showed increased cecal levels of total short chain fatty acids and butyrate, leading to a lower pH. Chick presented with lowered cecal indole and skatole concentrations, as did Cellulose. Cecal bacterial changes were notable in Chick, evidenced by differences in denaturing gradient gel electrophoresis banding patterns. However, representative bacteria quantified by real‐time PCR assay did not support this bacterial change. These results indicate that chickpea husk feeding can improve the antioxidative status of rats through its polyphenolic components and modulate the hindgut environment by its fibrous components.