Dynamic behavior of wood strip over elastic underlayment composite flooring subjected to light impact loads

Summary The dynamic behavior of composites consisting of wood flooring strips placed over rubber sheeting was investigated. A light impact load was applied to the center of the strips and impact force, contact duration and contact area were measured. The energy transfer from the impacting mass to the composite was estimated by measuring the restitution coefficient. Frequency analysis was conducted in order to examine the vibration characteristics of the composites.This study was carried out at the Forest Products Laboratory, University of California at Berkeley while the first author was a visiting scholar supported by the Science and Technology Agency, Japan     

Effects of utilization of local food by‐products as total mixed ration silage materials on fermentation quality and intake,digestibility, rumen condition and nitrogen availability in sheep

Four wethers were used in a 4 × 4 Latin square design experiment to evaluate in vivo digestibility of total mixed ration (TMR) silage with food by‐products for dairy cows, and the ruminal condition and nitrogen (N) balance were examined. Five by‐products (i.e. potato waste, noodle waste, soybean curd residue, soy sauce cake and green tea waste) were obtained. Four types of TMR silage were used: control (C) containing roughage and commercial concentrate, T1:20% and T1:40% containing the five by‐products replacing 20% and 40% of the commercial concentrate on a dry matter (DM) basis, respectively, and T2:40% containing three by‐products (potato waste, noodle waste and soybean curd residue) replacing 40% of the commercial concentrate on a DM basis. The ingredients were mixed and preserved in oil drum silos for 4 months. The TMR silages showed 4.02–4.44% and 1.75–2.19% for pH and lactic acid contents, respectively. The digestibility of DM and neutral detergent fiber, and total digestible nutrient content were higher (P < 0.05) for T2:40% feeding than for C feeding. Urinary nitrogen excretion tended to be lower (P = 0.07) for T2:40% than for C. The results suggested 40% replacing of commercial concentrate by using the three food by‐products can be most suitable for TMR silage.     

Transition of Historical Control Data for High Incidence Tumors in F344 Rats

Historical control data of tumor incidence were collected from the control groups (215 animals of each sex) in four recent carcinogenicity studies that were started between 2005 to 2009 (terminally sacrificed between 2007 and 2011) at BoZo Research Center Inc. (Gotemba, Shizuoka, Japan) using Fischer 344 rats (F344/DuCrlCrlj). These data were compared to the previous historical control data (from 1990 to 2004, previously reported) in the same facility. In the results, the incidence of C-cell adenoma in the thyroid tended to increase in both sexes in recent years (30.8% for males and 24.4% for females in 2005-2009) as compared with the previous data (17.4% and 20.1% for males and 11.5% and 11.8% for females in 1990–1999 and 2000–2004, respectively). In addition, the incidences of pancreatic islet cell adenoma in males and uterine adenocarcinoma tended to increase from around 2000 and remained high in recent years (incidences of islet cell adenoma in males of 10.5%, 17.1% and 20.5% in 1990–1999, 2000–2004 and 2005–2009; incidences of uterine adenocarcinoma of 3.3%, 12.0% and 13.5% in 1990–1999, 2000–2004 and 2005–2009, respectively). There was no apparent difference in the incidence of other tumors.     

Psychoacoustical evaluation of floor-impact sounds from wood-framed structures

Floor-impact sounds may introduce noise problems in dwelling-type environments. In particular, floor-impact sounds from lightweight structures like wood-framed buildings should be paid significant attention. In this study, such floor-impact sounds were investigated from the viewpoint of residents. The floor specifications of wood-framed structures were improved by using high-density underlay, and heavy floor-impact sounds were evaluated by using both psychoacoustical and conventional methods. The results showed that the floor-impact sound insulation grades specified in the Japanese Industrial Standards (JIS) did not correspond to the floor specifications of wood-framed structures. The nonstationary loudness, which is a psychoacoustical index for nonstationary sounds, changed with the specifications of wood-framed structures in a wider range of floor-impact sound levels in comparison with the maximum A-weighted sound pressure level, which is a single-number index of the JIS.     

Physiological and psychological responses to prolonged light floor-impact sounds generated by a tapping machine in a wooden house

We investigated the physiological and psychological responses of nine normal men to the prolonged light floor-impact sounds of 60dBA and 80dBA generated by a tapping machine in a two-story wooden house. Blood pressure was measured, and a sensory evaluation was also conducted using the semantic differential method. The results obtained were as follows: (1) the increase in systolic blood pressure immediately after exposure to the light floor-impact sounds depended on the level of the sounds, (2) the variations in feelings due to the prolonged light floor-impact sounds were identified by factor analysis, and (3) the subjects showed no difference in comfortable feeling for the prolonged light floor-impact sounds of 60dBA and 80dBA, but differences in the variation of the systolic blood pressure were detected.Part of this research was presented at the 47th Annual Meeting of the Japan Wood Research Society, Kochi, April 1997     

Waxy wheat as a functional food for human consumption

Waxy wheat (Triticum aestivum L.), a type of wheat that was first developed in Japan, produces grain amylopectin. I carried out three researches. Firstly, using Japanese adults, we carried out sensory evaluation of three types of mochi (a dumpling-like cake made of steamed and pounded grains) prepared from waxy wheat, normal wheat and waxy rice, and demonstrated that waxy wheat mochi had low adhesiveness and had the greatest ease of swallowing among the samples tested. Secondly, using the members of the JSDR (the Japanese Society of Dysphagia Rehabilitation) who attended the annual meeting, we performed another texture evaluations between waxy wheat and waxy rice mochi. The respondents reported waxy wheat mochi was less sticky and thus easier to chew and swallow than waxy rice mochi.     

Effect of conjugated linolenic acid (cis-9, trans-11, cis-13–18:3) on growth performance and lipid composition of fingerling rainbow trout Oncorhynchus mykiss

ABSTRACT:   This study investigated the effect of conjugated linolenic acid (CLNA) on the growth and lipid composition of fingerling rainbow trout Oncorhynchus mykiss . Thirty individuals in each tank with three dietary treatments and duplicate groups were subjected to three dietary levels (0:4, 2:2, 4:0) of CLNA and linolenic acid (LNA) at 16°C in the laboratory for a period of 9 weeks. Punicic acid ( cis -9, trans -11, cis -13–18:3) and linseed oil were used as sources of CLNA and LNA, respectively. The hepatosomatic index and body lipid content of the 2% CLNA dietary treatment increased significantly ( P  < 0.05) with respect to the control (LNA treatment). But the specific growth rate and percent gain did not improve significantly. After 6 weeks' observation, the 4% CLNA dietary treatment exhibited higher mortality and liver weight but lower weight gains (1.1–1.9 g). No significant differences were observed in the results of the feed efficiency and moisture as well as the protein content of the whole body among the treatments. Incorporation of CLNA into fish tissues was at a distinctly higher level in neutral lipids than in polar lipids. Increased levels of 22:6n-3 were found in the 4% CLNA treatment but decreased levels were found in the 2% CLNA treatment in both neutral and polar fractions. In the CLNA treatments, saturated fatty acid was relatively unaffected, the level of 18:1 was increased and the level of 18:2n-6 was decreased. These results indicate that the lower level (2%) of CLNA had no significant effect on the growth and the higher level (4%) of CLNA caused higher mortality as well as attenuating the growth of the fish. Dietary CLNA accumulated in a greater amount in the neutral lipids and modulated the fatty acid composition in the whole body of rainbow trout fingerlings.     

Background Data for General Toxicology Parameters in RccHan:WIST Rats at 8, 10, 19 and 32 Weeks of Age

Recently, RccHan(TM):WIST (Wistar Hannover) rats were introduced to toxicity studies in Japan. The present study was performed to obtain control data for general toxicological parameters as an aid for interpretation of results in toxicity studies using this strain of rats. Four test groups comprising of 25 male and 25 female RccHan(TM):WIST rats were housed for 2, 4, 13 or 26 weeks from 6 weeks of age and observed and examined for clinical observation, body weight, food consumption, urinalysis, hematology, blood chemistry, organ weight, necropsy and/or histopathology. Ophthalmological examination was not conducted in this study, and the data in this report were obtained from an ongoing 104-week background study in RccHan(TM):WIST rats. These data were compared with the historical control data of CD(SD) (Sprague-Dawley) and/or F344 (Fischer) rats. The body weights of RccHan(TM):WIST rats were lower than those of CD(SD) rats and higher than those of F344 rats. The ophthalmological examination revealed a greater incidence of focal corneal opacity. Histopathology revealed focal mineralization of the cornea and Berlin blue-positive pigmentation in the epididymal interstitium as well as hepatocytes. Other than the above, some minor differences were found in urinalysis, hematology, blood chemistry and organ weights as compared with CD(SD) rats.     

Application of microparticle diets for Japanese flounder Paralichthys olivaceus larvae

ABSTRACT:   A feeding trial was conducted with two newly developed microparticle diets (MD-Q and MD-V), which differed in the mixing ratios of two types of casein hydrolysates (C700 and C800) as the protein source. The ratio of C700 and C800 were adjusted to 7:3 in MD-Q and 6:4 in MD-V, respectively. Japanese flounder larvae were fed from 7 days after hatching (d.a.h.) to 32 d.a.h. on live food (LF), MD solely, MD + 1/3 LF (either of the MD and one-third quantity of the live food) and 1/3 LF (one-third quantity of live food alone), respectively. They were then switched to Kyowa diet B from 33 d.a.h. until 40 d.a.h. The larvae fed on MD-Q exclusively had a higher survival rate (36.4%) than those fed on MD-V (24.2%) by 22 d.a.h. Unfed larvae could survive up to only 12 d.a.h. Larvae fed on MD-Q + 1/3 LF also had a significantly higher survival rate (34.2%) than those on MD-V + 1/3 LF (16.3%) and 1/3 LF solely (15.4%) at 32 d.a.h. These results suggest the potential of MD-Q as a part replacement for LF from the early developmental stage in the seed production of Japanese flounder.