Defect detection in lumber including knots using bending deflection curve: comparison between experimental analysis and finite element modeling

A new method has been developed for detecting localized defects such as edge knots using a bending deflection curve. The coordinates of a bottom edge (edgeline) of an unloaded piece of lumber are extracted from a digital image, and a bending deflection curve is obtained from the displacement of the edgeline of the lumber using a digital image correlation (DIC) technique. Depending on the knots within the beam, the bending deflection curve is shifted from the curve of a defect-free beam. The measured bending deflection curve is regressed to a theoretical curve by elementary beam theory. A finite element method (FEM) model of the beams including defects as simplified knot structure has been performed. Comparison between the bending experiment and FEM analysis shows that cross-sectional reductions cause characteristic variations in the bending deflection curves depending on the position of encased knots, and local grain distortions cause variations in the curves depending on the direction of spike knots. Using the residual variance between the measured deflection curve and a polynomial regression curve, it is possible to detect knots at which failures initiate. Part of this article was presented at the 57th Annual Meeting of the Japan Wood Research Society, Hiroshima, Japan, August 2007     

Analysis of the relationship between DBH and crown projection area using a new model

Relations of DBH-crown projection area (CPA) were studied for deciduous and coniferous trees with different models, one of which is newly derived this time. For DBH-CPA relations, a proposed power-sigmoid function was the most suitable one among four models because of its good fit and mechanistic meaning. This model contains the feature that CPA grows with the second power relation to DBH, and the increasing rate of CPA slows as DBH increases. With transformation, the power-sigmoid function for DBH-CPA relation can be applied for individual basal area (IBA)-CPA relations as single-saturate function, and these two functional models have high compatibility. Next, the differences of DBH-CPA between deciduous and coniferous tree groups were analyzed with power-sigmoid function. The initial increasing rates of CPA against DBH for each group were similar, though the CPA's increasing rate for the coniferous group tended to decrease earlier than for the deciduous group. Because the power sigmoid function has mechanistic meanings, one can separately analyze the attributes of the DBH-CPA relation: the initial increasing rate of CPA and final tree form.     

Plasma concentrations of immunoreactive (ir)-inhibin, gonadotropins and steroid hormones during the ovulatory cycle of the duck

The present study was undertaken to determine changes in circulating levels of immunoreactive (ir)-inhibin, FSH, LH, estradiol-17beta, progesterone, and testosterone during the ovulatory cycle of Shao ducks. Serial blood samples were taken from two groups of laying ducks for measurement of ir-inhibin, gonadotropins, and steroid hormones at 2 h intervals for 24 h. Plasma concentrations of ir-inhibin did not change significantly during the ovulatory cycle. The highest level of plasma ir-inhibin was observed 6 h prior to ovulation, which coincided with a decreased level of plasma FSH. One FSH surge was found 12 h after ovulation. Estradiol-17beta, progesterone, and testosterone were also determined during the ovulatory cycle. Two peak values were detected for estradiol-17beta 8 h before ovulation and 4 h after ovulation, while progesterone started to increase 4 h before ovulation and reached a peak at ovulation. The highest level of plasma testosterone was detected around the time of ovulation. These results suggest that inhibin may be involved in the control of FSH secretion during the ovulatory cycle. In addition, both LH and progesterone are of importance in the ovulation process of Shao ducks.     

Immunolocalization of inhibin/activin subunits in the shiba goat fetal, neonatal, and adult testes

The objective of this study was to investigate the cellular immunolocalization of inhibin alpha and inhibin/activin (betaA and betaB) subunits in the fetal, neonatal and adult testes of Shiba goats. The testes were obtained from a fetus at 90 days, a neonate at 15 days, and two adult Shiba goats (both of 3 years old). The sections of testes were immunostained by the avidin-biotin-peroxidase complex method (ABC) using polyclonal antisera raised against porcine inhibin alpha, inhibin/activin betaA, and inhibin/activin betaB. Inhibin alpha and inhibin/activin (betaA and betaB) subunits were expressed in Leydig cells, but not in the Sertoli cells of the fetus with a weak immunostaining. An increase in the number of positive cells and a more intense immunohistochemical signal for inhibin alpha and inhibin/activin (betaA and betaB) subunits were observed in the Leydig cells of neonatal testes. Moreover, inhibin alpha, betaA, and betaB subunits were expressed in the Sertoli cells and Leydig cells of adult testes, respectively. These results suggest that Shiba goats testes have the ability to synthesize inhibins in the fetus, neonate, and adult, and the cellular localization of inhibin/activin subunits showed age-related changes in fetal, neonatal, and adult testes of Shiba goats.     

Activation and penetration in vitro of pig oocytes treated with calcium ionophore

The present study examined the effects of pre-treatment of pig oocytes with different concentrations (0-50 microM) of calcium ionophore A23187 (CaA) on their activation, development and penetration in vitro. Although untreated oocytes were not activated and did not cleave in culture, high proportions of treated oocytes did so and 20% of oocytes developed to the blastocyst stage when treated with 6.25 microM CaA for 2 min. However, these proportions were reduced in a concentration-dependent manner. When inseminated in vitro with 1 x 10(6) spermatozoa/ml, the penetration rate of oocytes treated with 6.25 microM CaA was similar to that of untreated oocytes. However, fewer oocytes treated with 12.5 and 50 microM CaA were penetrated than untreated oocytes. On the other hand, the proportion of monospermy of oocytes treated with 6.25 microM CaA was higher than the values in oocytes not treated or treated with 50 microM CaA. The time required for zona dissolution of oocytes treated with 6.25 and 12.5 microM CaA was not different from that in untreated oocytes, but oocytes treated with 50 microM CaA required a longer time than untreated oocytes, indicating that zona solubility by protease does not reflect penetrability of oocytes in vitro. When oocytes were inseminated with different concentrations (1-10 x 10(6) cells/ml) of spermatozoa, the highest penetration rate was observed at 1 x 10(6) cells/ml in untreated oocytes and a similar result was obtained in oocytes treated with 6.25 microM CaA. There was no difference in the rate of monospermy in untreated oocytes among different concentrations of spermatozoa, but in treated oocytes, higher proportions of monospermy were observed at 0.5-5 x 10(6) than 10 x 10(6) cells/ml. At 1 x 10(6) cells/ml, the proportion of monospermy was higher in treated than untreated oocytes. These results suggest that pre-treatment of pig oocytes with 6.25 microM CaA, an appropriate concentration, inhibits polyspermic penetration in vitro when insemination occurs with spermatozoa at a concentration of 1 x 10(6) cells/ml.     

Birth of piglets through the non-surgical transfer of blastocysts produced in vitro

In this study, we attempted to produce piglets by non-surgically transferring blastocysts produced in vitro, using a flexible catheter as the transfer instrument. Cumulus-oocyte complexes (COCs) were aspirated from the follicles of ovaries obtained at a local slaughterhouse. They were then matured in modified North Carolina State University (NCSU)-37 medium for 44-46 h and fertilized in porcine gamete medium (PGM). Ten hours after in vitro fertilization (IVF), presumptive zygotes were removed from the cumulus cells and cultured in porcine zygote medium (PZM)-5. Blastocysts were cultured for five days after IVF and, using a catheter for deep intrauterine insemination without sedation, they were transcervically transferred into the uterine horn of six recipients (45-50 blastocysts/recipients) whose estrous cycles were synchronized, at 5 days after human chorionic gonadotropin (hCG) injection. Of the six recipients, one sow became pregnant and farrowed seven piglets (four live piglets) 119 days after hCG injection. The body weight at birth of the newborns ranged from 0.8 to 1.4 kg. These results indicate that it is possible to obtain piglets by transcervically transferring blastocysts produced by IVF and in vitro cultures in chemically defined media.     

Diagnosis of histoplasmosis by detection of the internal transcribed spacer region of fungal rRNA gene from a paraffin-embedded skin sample from a dog in Japan

The lesions of histoplasmosis in dogs in Japan differ from those in dogs in North America. Affected dogs in Japan have had multiple granulomatous or ulcerated foci in skin or gingiva and have not had pulmonary or gastrointestinal lesions. The present report introduces a polymerase chain reaction (PCR) diagnosis of canine histoplasmosis and the characteristic of disease in Japan. The surgically removed skin ulcerate samples from a 5-years-old female Shiba-inu native to Japan without traveling out of the country were evaluated. Tissue samples had many yeast-like organisms in the macrophages. DNA was extracted from paraffin-embedded tissue samples. A nested PCR technique was applied. The detected sequence of the internal transcribed spacer of ribosomal RNA gene had 99.7% in homology with Ajellomyces capsulatus (the teleomorph of Histoplasma capsulatum). Clinical manifestations, historical background of equine epizootic lymphangitis in Japan, and a human autochthonous case of histoplasmosis farciminosi indicated that this dog might have been infected with H. capsulatum var. farciminosum as a heteroecism.     

Vascular endothelial growth factor (VEGF) promotes the early development of bovine embryo in the presence of cumulus cells

Three experiments were conducted to determine the effect of Vascular Endothelial Growth Factor (VEGF) on bovine embryonic development in vitro. Human recombinant VEGF(165) was employed at 5 ng/ml in modified synthetic oviduct fluid. In Exp. 1, bovine cumulus oocyte complexes were matured with or without VEGF for 22 hr, inseminated without VEGF for 6 hr, then cultured with or without VEGF for 42 hr. The cleavage rate and the development rate to 4- to 8-cell were higher (P<0.05) in groups with VEGF during in vitro maturation (IVM, 71.4% and 59.6%), in vitro culture (IVC, 70.3% and 62.3%), and both IVM and IVC (75.9% and 67.8%) than in the group cultured thoroughly without VEGF (49.9% and 38.4%, respectively). In Exp. 2, 4- to 8-cell embryos produced in vitro without VEGF were removed from cumulus cells at 48 hr post-insemination (Pi) and cultured with or without VEGF for 144 hr. The development rates to blastocyst at 96 hr (D6), 120 hr (D7) and 144 hr (D8) were similar (P>0.05) in both groups. In Exp. 3, cumulus cells were removed from presumptive embryos produced by IVM and IVF without VEGF at 10 hr Pi. Denuded embryos were cultured with or without VEGF for 38 hr or 182 hr. The cleavage rate and the development rates to 4- to 8-cell at 48 hr Pi and to blastocyst on D6, D7 and D8 were similar (P>0.05) in all groups. These results suggest that VEGF has a beneficial effect on the initial development of bovine embryo through surrounding cumulus cells.