Extractives of muirapiranga (<Emphasis Type="Italic">Brosimun</Emphasis> sp.) and its effects on the vibrational properties of wood

The potential of muirapiranga (Brosimun sp.) as a substitute material for violin bows was estimated in terms of vibrational properties, and the influence of extractives on the vibrational properties was examined. The loss tangent of muirapiranga was somewhat higher and the specific dynamic Young’s modulus was rather lower than the respective values for pernambuco, which is regarded as the best material for violin bows. Therefore, muirapiranga is a poorer bow material in terms of vibrational properties. Impregnation of crude extractives from muirapiranga decreased the loss tangent of other wood specimens. The main compounds of the extractives were identified as xanthyletin and luvangetin. Impregnations of isolated xanthyletin and commercially available methoxsalen, which was tested as an analogue of luvangetin, markedly decreased the loss tangent of other wood specimens. Methoxsalen and xanthyletin differ from conventional loss tangent-decreasing substances, namely protosappanin B and hematoxylin, in terms of water insolubility and the absence of hydroxyl groups. From the similarity in molecular characteristics of loss tangent-decreasing substances found so far, restriction of molecular motion due to an impregnated substance in the wood matrix is suggested as one loss tangent-decreasing mechanism.     

Reversible volumetric changes of acetylated wood with after-treatments

Dimensional changes of acetylated wood were measured during wet–dry cycling and heating to clarify the reversible and irreversible effects of those after-treatments. During wet–dry cycling, the acetylated wood showed slight swelling in its completely dry condition, while its weight decreased slightly. Similar swelling was recognized when the acetylated wood was heated dry above 140°C. On the other hand, the anomalous effects of wet–dry cycling and heating disappeared after soaking in acetone. It was considered that the rearrangement of hydrophobic wood polymers during wet–dry cycling and heating induced the expansion of voids, whereas the wood polymers recovered their initial conformation after soaking in organic liquids. The wet volume of acetylated wood also exhibited reversible changes during wet–dry cycling. Just after the acetylation, the wood was highly swollen in acetic anhydride. The swollen volume of acetylated wood was reduced by leaching in water, and additional decrease in the wet volume resulted from the following drying or boiling. However, the reduced wet volume was recovered almost completely after acetone-soaking. These results suggested that the water molecules remaining in the hydrophobic region expanded the wet volume of acetylated wood, while such weakly bound water was easily removable by drying or boiling.     

Shrinkage of cane (<Emphasis Type="Italic">Arundo donax</Emphasis>) I. Irregular shrinkage of green cane due to the collapse of parenchyma cells

Shrinkage of green cane (Arundo donax L.) was measured during air-drying at room temperature. The cane began to shrink at 150% moisture content due to a remarkable collapse of parenchyma cells. The collapse recovered after boiling in water, but more serious collapse (recollapse) was induced by the following drying. On the other hand, the collapse recovered almost completely after steaming with saturated water vapor at 92°–96°C without recollapse. By comparing the thickness of cane specimens before and after steaming, the degree of cell collapse remaining in dry cane was evaluated. When the green cane was frozen prior to drying, the degree of collapse was reduced whereas the drying rate remained unchanged. The effect of prefreezing was interpreted as the generation of air bubbles in the cell lumen which hinder the effective loading of liquid tension on the cell wall. Even when the cane was carefully dried using a conventional method used by reed manufacturers, the degree of collapse was very large and it increased with elevating internode position.     

Effects of temporary cessation of milking following intramammary cefazolin sodium infusion on residual antibiotic in lactating dairy cows

The aims of studies were to estimate the withdrawal period of antibiotic from milk after the intramammary infusion of cefazolin sodium (CEZ) in cows with difficulties in frequent milk discharge due to disease such as teat injury. The period was compared among cows milked twice a day after 150 or 450 mg of CEZ were administered to all quarters (Study 1, 2) and the cows in which milking of front-right quarter was ceased for five days after administration of these infusions to only that quarter (Study 3). In Studies 1 and 2, the median of 17.66 µg/ml and 83.18 µg/ml of CEZ were detected in the samples of first milking after intramammary administration, respectively; however, there was no residual antibiotic by 72 hr in all cows. In Study 3, the median of 1.96 µg/ml of CEZ was detected in the sample after the resumption of milking at 120 hr, and the residual was eliminated by 174 hr. The withdrawal period may be prolonged by the cessation of milking after administration, and the period is the total time from cessation to 72 hr after the resumption of milking.     

Histological observation of the reproductive system in a viviparous teleost Xenotoca eiseni Rutter 1896 (Cyprinodontiformes: Goodeidae)

Xenotoca eiseni is a viviparous teleost belonging to the family Goodeidae. Here, we report histological observations of the reproductive organs in an adult male, an adult female, a pregnant female with intraovarian embryo and an extracted embryo of X. eiseni. High-resolution images of haematoxylin–eosin-stained sagittal sections revealed the detailed structure of gonads, gametes and reproductive components of the mother–embryo relationship. In the male, mature spermatozoa in the epididymis formed sperm packages. In the female, oogenesis proceeded asynchronously in the ovarian wall, and various stages of oocytes were observed in single ovary. In both sexes, genital openings were located between the anus and anal fin. Developing embryos were observed in an ovary of the pregnant female. Fine structures of components of the mother-to-embryo nutrient supply, ovarian septum and trophotaenia were observed in the pregnant ovary. An immature gonad prior to gamete formation was identified in the extracted embryo. With the aim of supporting the development and extension of studies on this viviparous teleost, we have shared our histological images as raw data in an open online archive, the 'NAGOYA repository ( http://hdl.handle.net/2237/00032456 )'. Our goal is a comprehensive understanding of the viviparous system in fish using both histological observation and molecular biology methods including genomics and proteomics.     

Present situation and cause analysis of diversion dam failures in Japan

Diversion dams are settled in river channels to dam water. They obstruct flood flow and also affect sediment movement on riverbeds. Dam structures break due to local scouring of the riverbed caused by local flow around them. The causes of such failures should be studied by investigating how flow meanders over alternate bars during floods. Diversion dam failures are classified into three types according to cause. The first type of problem is caused by the difference between the riverbed height and the sill height. If the present riverbed is higher than the sill, the mobile gates do not close easily due to sand deposition on the sill. If the riverbed is lower than the sill, the riverbed in the downstream area of the weir is scoured, and the weir may be damaged. The second type is caused by the relation of the weir position to the alternate channel bars. The bar area is usually higher than the sill, and sand deposition on the sill causes problems for mobile gate operation. The riverbed below the weir at the pool section is scoured because the bed height is lower than the sill height. The third type is caused by the migration of alternate bars. A low water course changes due to migration of alternate bars after a flood. The sand deposition area from the upstream reach blocks the intake entrance. Before a diversion dam structure is designed, the situation and the probable changes in riverbed form should be investigated.     

Molecular cloning and characterization of oryzacystatin-III, a novel member of phytocystatin in rice (Oryza sativa L. japonica)

On the basis of cDNA sequences, we found that the calli of rice encodes an amino acid sequence that shares 56% and 89% identity, respectively, with oryzacystatin-I and oryzacystatin-II. This sequence differs from that of oryzacystatin-II in the N-terminal region (Gln(7)-Ala(19) in the oryzacystatin-III numbering), and this region contained a glycine residue (Gly(14)), which is evolutionarily conserved in the cystatin superfamily. We named this novel protein oryzacystatin-III. Nucleotide sequencing of the 5'-flanking region of the oryzacystatin-III gene showed that it is highly homologous to the oryzacystatin-II gene but distinct from the oryzacystatin-II locus. Oryzacystatin-III inhibited papain, ficin, and human cathepsin B. The inhibition constants for papain and ficin differ from those of oryzacystatin-I and -II, and cathepsin B activity is affected only by oryzacystatin-III, showing differences in the interaction of these inhibitors with enzymes. These data suggest that the above three inhibitors may play unique physiological roles in the regulations of rice cysteine proteinases.     

Regional Distribution of Natural Stream Nitrate in Central Japan

Over 60 natural streams with forested catchments were surveyed for nitrate (NO₃ ^?) concentration in central Japan. Stream NO₃ ^? concentrations showed a clear zonal gradient with a range nearly as large as 100-fold, where their small seasonal variations (av. CV = 27%) justified respective statuses. Elevated NO₃ ^? concentrations (more than 70 µM) described a distribution of N saturation along a course of polluted air advection in the Kanto Plain. The extent of NO₃ ^? leaching from forests was not proportional to atmospheric N deposition probably because of ecosystem N retention. A dependency of NO₃ ^? level on the watershed altitude and quite constant δ¹⁵N of stream NO₃ ^? over a wide NO₃ ^? range were observed, which could be also related to this cause.     

Oxidative stability of lipids from squid tissues

ABSTRACT: Oxidative stability of lipids from squid tissues was compared with those of other marine lipids. On the basis of peroxide formation, total lipids (TL) from squid viscera or squid muscle with skin were most oxidatively stable, followed by squid eye TL, trout egg TL, bonito oil, and tuna orbital TL, respectively. This tendency in oxidative stabilities was also confirmed by the decrease in unoxidized polyunsaturated fatty acids during oxidation. Analyses of tocopherol contents and lipid compositions suggested that the higher oxidative stabilities of three kinds of squid tissue TL and trout egg TL compared to those of bonito oil and tuna orbital TL would be mainly because of the presence of phospholipids (PL) in squid tissue lipids and trout egg TL. However, the oxidative stability of lipids containing PL did not always decrease with increasing PL contents and stability was strongly influenced by PL composition. As squid viscera contained more than 25% of TL and these lipids were oxidatively stable, squid viscera may be used as a good resource of functional lipids rich in eicosapentaenoic acid and docosahexaenoic acid.     

Reduction of ammonia emission from growing pig rooms by feeding a lower protein diet supplemented with apple pomace

An experiment was conducted to determine the effect of supplementing a reduced crude protein (CP) diet with apple pomace on the ammonia emissions from growing pig rooms. Four pigs (45 kg BW) each were assigned to one of two diets. Each group was housed in a separate room and fed a standard diet (CP 16.6%) or a low CP, amino acid‐supplemented diet (CP 9.1%) containing 23.1% of dried apple pomace for two 7‐day experimental periods. After the completion of the first period, the pigs were switched to the other diet. The daily ammonia emissions, measured for 3 days after a 4‐day adaptation period, were much lower for pigs fed the apple pomace‐supplemented diet than for pigs fed the standard diet (0.47 g/pig vs 7.30 g/pig, respectively). The daily nitrogen intake for the standard diet and the apple pomace‐supplemented diet was 58.1 and 35.5 g/pig, respectively. The pigs fed the apple pomace‐supplemented diet excreted more fecal nitrogen than pigs fed the standard diet (17.5 g/day vs 11.0 g/day, respectively), but urinary nitrogen excretion with the apple pomace‐supplemented diet was estimated to be 2.9 g/day, which was much lower than that for the standard diet (27.0 g/day). The addition of apple pomace to a reduced CP, amino acid‐supplemented diet reduces urinary nitrogen excretion and thereby ammonia emission.