bluuebunny/crossref_metadata_2025 huggingface dataset:
Elastic to elastic–plastic transition of Al2O3/TiC ceramics studied by nanoindentation
Authors: Zimmermann Katrin , Schneider Gerold A.
Published: May 2009

In this work load–penetration curves obtained by nanoindentation were analyzed, using a spherical tip approximation and applying the stress/strain concept by Tabor. Nanoindentation experiments were done on sapphire, pure TiC, and a mixed ceramic with in situ formed TiCxlayer, using a sharp cube-corner indenter at very low loads and penetration depths. With the implemented method it is possible to display the elastic to elastic–plastic transition of each investigated phase, and much more information can be extracted than by conventional analysis. Regarding the mixed ceramic, it was found that the present TiC phases exhibit slightly lower hardness than the alumina phase, but they can sustain much higher stresses during the transition from the elastic to the elastic–plastic regime. This is considered to be beneficial for the application as cutting material. No correlation was found between the nanomechanical behavior of the model materials sapphire and TiC and the corresponding phases of the mixed ceramic.
Preferential growth and orientation relationship of Ag3Sn grains formed between molten Sn and (001) Ag single crystal
Authors: Zou H.F. , Yang H.J. , Tan J. , Zhang Z.F.
Published: May 2009

The current study shows that there is a preferred orientation relationship between Ag3Sn and Ag in reaction between molten Sn and Ag. Due to the preferred orientation relationship, the morphology of Ag3Sn grains formed on (001) Ag single crystal is different from those formed on (011), (358) single crystal Ag, and polycrystalline Ag Facet scallop-type Ag3Sn grains formed irregularly on (011), (358) single crystal Ag, and polycrystalline Ag; whereas the regular Ag3Sn grains with parallel edges grew on (001) Ag single crystal, and they were elongated along two perpendicular directions. The orientation relationship between Ag3Sn grains and (001) Ag single crystal was determined using electron backscattered diffraction. The preferential growth of regular Ag3Sn grains with parallel edges formed on (001) Ag single crystal can be attributed to their minimum misfit.
Nitriding of yttria-stabilized zirconia in atmospheric pressure microwave plasma
Authors: Milani R. , Cardoso R.P. , Belmonte T. , Figueroa C.A. , Perottoni C.A. , Zorzi J.E. , Soares G.V. , Baumvol I.J.R.
Published: May 2009

High temperature plasma nitriding of yttria-partially-stabilized zirconia in atmospheric pressure microwave plasma was investigated. The morphological, mechanical, and physicochemical characteristics of the resulting nitrided layer were characterized by different methods, such as optical and scanning electron microscopy, microindentation, x-ray diffraction, narrow resonant nuclear reaction profiling, secondary neutral mass spectrometry, and x-ray photoelectron spectroscopy, aiming at investigating the applicability of this highly efficient process for nitriding of ceramics. The structure of the plasma nitrided layer was found to be complex, composed of tetragonal and cubic zirconia, as well as zirconium nitride and oxynitride. The growth rate of the nitrided layer, 4 µm/min, is much higher than that obtained by any other previous nitriding process, whereas a typical 50% increase in Vickers hardness over that of yttria-partially-stabilized zirconia was observed.
Bone-like growth of hydroxyapatite in the biomimetic coating of Ti-6Al-4V alloy pretreated with protein at 25 °C
Authors: Chakraborty Jui , Mazaj Matjaz , Kapoor Renu , Gouri S. Pavana , Daneu Nina , Sinha Mithlesh K. , Pande Gopal , Basu Debabrata
Published: May 2009

Commercial-grade dense Ti-6Al-4V alloy substrate was mechanically roughened, cleaned, and treated with a globular protein [bovine serum albumin (BSA)] for 4 h. Biomimetic calcium phosphate (Ca-P) coating was applied onto the above-treated substrate by immersion into simulated body fluid (SBF) at 25 °C for a period of 4 days, with periodic replacement by freshly prepared SBF at 48-h intervals. After 4 days, branched micron-sized fibers of hydroxyapatite (HAp), resembling the structure of bone, were obtained, connecting the clusters of HAp crystal plates in the coating (thickness ∼200 μm) on the substrate surface. Structural and compositional characterization of the coating was carried out using field emission scanning electron microscopy (FE-SEM) with energy-dispersive x-ray analysis unit (EDX) facility, x-ray diffraction (XRD), and Fourier transform infrared (FTIR) data. In vitro cytotoxicity (ISO 10993-5, 1999), cell adhesion assays, and phase contrast microscopy were performed using NIH 3T3 fibroblast cell lines to ascertain the bioactivity of the coated substrates, with and without protein treatment. Based on our study, we propose a correlation between a specific physical structure of the HAp coating and its biological properties.
Cavitation damage incorporating cavity growth in submicrometer-grained titanium alloy
Authors: Ko Young Gun , Shin Dong Hyuk , Lee Chong Soo
Published: May 2009

A study was made to investigate cavity growth behavior during the superplastic deformation of submicrometer-grained titanium alloy and to compare that to cavity growth in a coarse-grained counterpart. A series of tension tests were performed at a temperature of 973 K and a strain rate of 10−4 s−1. Microstructures revealed that both the size and the volume fraction of the cavities obviously decreased as the grain size decreased. Working within the framework provided by creep models for understanding cavity growth behavior, we found the dominant growth mechanism to be superplastic diffusion, which leads to high-tensile ductility in submicrometer-grained titanium alloy.
Mg–Ni–(Gd,Nd) bulk metallic glasses with improved glass-forming ability and mechanical properties
Authors: Yin J. , Yuan G.Y. , Chu Z.H. , Zhang J. , Ding W.J.
Published: May 2009

In this work, we report a new Mg-based glass-forming system of Mg–Ni–(Gd,Nd), which can be produced into glassy rods with maximum diameters of 2–5 mm by copper mold casting. The Mg75Ni15Gd10–xNdx(x = 0–10) BMGs simultaneously possess a high level of glass transition temperatures, high specific strength up to 2.75 × 105 Nm/kg, and enhanced malleability with plastic strains over 1%. In particular, the Mg75Ni15Gd5Nd5 BMG with the glass-forming ability (GFA) up to 5 mm, exhibited compressive yield strength over 900 MPa and plastic strain up to 50% without failure for the specimen with an aspect ratio of 0.5. The improved GFA and malleability for the Mg75Ni15Gd10–x Ndx(x = 0–10) BMGs were discussed, which exhibited their promising potentials for the application as lightweight engineering materials.
Shape-memory NiTi–Nb foams
Authors: Bansiddhi Ampika , Dunand David C.
Published: May 2009

A new powder metallurgy technique for creating porous NiTi is demonstrated, combining liquid phase sintering of prealloyed NiTi powders by Nb additions and pore creation by NaCl space-holders. The resulting foams exhibit well-densified NiTi–Nb walls surrounding interconnected pores created by the space-holder, with controlled fraction, size, and shape. Only small amounts of Nb (3 at.%) are needed to produce a eutectic liquid that considerably improves the otherwise poor densification of NiTi powders. NiTi–Nb foams with 34–44% porosity exhibit high compressive failure stress (>1,500 MPa), ductile behavior (>50% compressive strain), low stiffness (10–20 GPa), and large shape-memory recovery strains. These thermomechanical properties, together with the known biocompatibility of the alloy, make these open-cell foams attractive for bone implant applications.
Effects of size and surface on luminescence properties of submicron upconversion NaYF4:Yb,Er particles
Authors: Yuan Du , Shun Yi Guang , Chow Gan Moog
Published: May 2009

Bulk NaYF4:Yb,Er particles (∼1.4 μm particle size) were synthesized using a hydrothermal method. As-synthesized particles were subsequently ball milled to three average particle sizes, namely, ∼260 nm, 160 nm, and 100 nm. The x-ray diffraction pattern showed an hcp phase for as-synthesized and ball-milled particles with a predominant (100) peak. Room temperature emission spectra showed no size dependent peak shifts or peak broadening. The intensities of both green and red emissions decreased with increasing milling time. Segregation of Er ions was detected on the surfaces of milled particle that reduced the sensitizer-activator transition probability, resulting in decreased emission intensities. The green-to-red emission ratio was correlated to the surface enrichment of Er, which affected the cross-relaxation of luminescence dynamics.
Seeking Psychosocial Care After Interpersonal Violence: An Integrative Model
Authors: Schreiber Viola , Renneberg Babette , Maercker Andreas
Published: May 2009

Many people experience a traumatic event at least once in their lifetime. But only a fraction of those traumatized and in need of mental health care receive psychosocial care or treatment. This may be due to barriers people experience within the help-seeking process. The individual help-seeking process is consequently highly relevant for any mental health care for trauma survivors. Understanding why people refrain from asking for help or delay the help-seeking process is central to understanding help-seeking after traumatization. Based on empirical data and theoretical models, an integrative model of individual mental health help-seeking is developed. This integrative model delineates parameters relevant for seeking psychosocial care or refraining from it.
Intimate Partner Violence and Risk for Depression Among Postpartum Women in Lima, Peru
Authors: Gomez-Beloz Alfredo , Williams Michelle A. , Sanchez Sixto E. , Lam Nelly
Published: May 2009

A cross-sectional study of 2,317 women who delivered at Instituto Nacional Materno Perinatal, Lima, Peru, was carried out to evaluate risk of depression in relation to maternal experience with intimate partner violence (IPV) before and during pregnancy. Depression severity was assessed using the Patient Health Questionnaire Depression Subset (PHQ-9). The prevalence of IPV during lifetime and pregnancy was 44% and 21%, respectively. Adjusted odds ratios and 95% confidence intervals for each level of depression severity associated with history of IPV during pregnancy were: mild 1.4 (1.9–2.3); moderate 2.9 (1.8–4.5); moderately severe 5.5 (3.4–9.2); and severe 9.9 (5.1–19.9). A positive gradient was observed for severity of depression and IPV during pregnancy (trend p < 0.001). Postpartum women who experienced IPV during pregnancy had higher levels of depression severity than did nonabused women.
History of Abuse and Psychological Distress Symptoms Among Female Sex Workers in Two Mexico–U.S. Border Cities
Authors: Ulibarri Monica D. , Semple Shirley J. , Rao Swati , Strathdee Steffanie A. , Fraga-Vallejo Miguel A. , Bucardo Jesus , De la Torre Adela , Salázar-Reyna Juan , Orozovich Prisci , Staines-Orozco Hugo S. , Amaro Hortensia , Magis-Rodríguez Carlos , Patterson Thomas L.
Published: May 2009

This study examined histories of past emotional, physical, and sexual abuse as correlates of current psychological distress using data from 916 female sex workers (FSWs) who were enrolled in a safer-sex behavioral intervention in Tijuana and Ciudad (Cd.) Juarez, Mexico. We hypothesized that histories of abuse would be associated with higher symptom levels of depression and somatization and that social support would moderate the relationship. Nonparametric correlations and a series of hierarchical regression analyses revealed that all forms of past abuse predicted higher levels of depressive symptoms, and physical and sexual abuse were significantly associated with higher levels of somatic symptoms. Social support was also significantly associated with fewer symptoms of distress; however, it was not shown to moderate the relationship between abuse history and distress.
Effects of synthetic gestagens on fish reproduction
Authors: Zeilinger Jana , Steger-Hartmann Thomas , Maser Edmund , Goller Stephan , Vonk Richardus , Länge Reinhard
Published: May 2009

Although it is well known that estrogenic steroidal hormones are able to affect the sexual development and reproduction of fish at low concentrations, no data on environmental effects of the class of progestogenic hormones are available yet. Synthetic gestagens (progestins) are a component in oral contraceptives. Upon their use, a fraction of the progestins will be excreted via urine into the aquatic environment. On the basis of their pharmacological action in mammals, it is supposed that fish reproduction is the most sensitive endpoint for the progestin treatment. In order to test this assumption, the effects of two progestins currently marketed in contraceptive formulations, levonorgestrel (LNG) and drospirenone (DRSP), were investigated in adult fathead minnows (Pimephales promelas) following an Organization for Economic Cooperation and Development 21-d fish reproduction screening assay draft protocol with additional end points. Levonorgestrel was tested at measured concentrations of 0.8, 3.3, and 29.6 ng/L, and DRSP at concentrations of 0.66, 6.5, and 70 μL. Both tested progestins caused an inhibition of reproduction. For LNG, this occurred at concentrations of 2:0.8 ng/L, no no-observed-effect concentration (NOEC) could be defined. Higher concentrations resulted in masculinization of females with de novo synthesis of nuptial tubercles. Drospirenone treatment, however, affected the reproductive success of fathead minnow at concentrations of 6.5 μL and higher with a clear dose-response relationship and a NOEC of 0.66 μL, which is above environmentally relevant concentrations.
Advanced fluorescence in situ hybridization to localize and quantify gene expression in Japanese medaka (Oryzias latipes) exposed to endocrine-disrupting compounds
Authors: Park June-Woo , Tompsett Amber R. , Zhang Xiaowei , Newsted John L. , Jones Paul D. , Au Doris W. T. , Kong Richard , Wu Rudolf S. S. , Giesy John P. , Hecker Markus
Published: May 2009

In an earlier study, we described the development of fluorescence in situ hybridization (FISH) using confocal microscopy to localize and quantify gene expression in fish. Here, we report the results of FISH application to investigate effects of model endocrine-disrupting chemicals (EDCs), 17α-ethinylestradiol (EE2) and 17β-trenbolone (TB), on expressions of EDC-responsive genes in Japanese medaka (Oryzias latipes) at the cellular/tissue level paired with histological observation. Gene expressions of vitellogenin-II (Vit-II), androgen receptor (AR), and cytochrome P450 gonadal aromatase (CYP19a) were determined after exposure to 5, 50, or 500 ng/L of EE2 or 50, 500, or 5,000 ng/L of TB for 7 d. Exposure to the greatest concentration of EE2 or TB significantly reduced fecundity and caused histological alterations in gonads. 17α-Ethinylestradiol induced Vit-II expression in both male gonads and liver relative to controls and resulted in greater intensity of hematoxylin staining in hepatocytes, which was significantly correlated with Vit-II induction in liver. When exposed to EE2 at less than 50 ng/L, CYP19a expression associated with early stage oocytes was greater than that in controls. However, at 500 ng/L, this trend was reversed. The greater Vit-II expression in testis from all EE2 groups, and the lesser expression of CYP19a in ovaries from the 500 ng/L group, likely is related to changes in the number of cells in which these genes are predominantly expressed rather than to an increase in expression per cell. 17β-Trenbolone significantly induced AR expression in ovaries but did not alter AR expression in female liver. It was concluded that FISH combined with histology enables advanced elucidation of molecular effects of chemicals by associating changes in gene expression with certain tissues and/or cell types and allows these changes to be related to histological effects.
Identification of a Critical Novel Mutation in the Exon 1 of Androgen Receptor Gene in 2 Brothers With Complete Androgen Insensitivity Syndrome
Authors: Radpour Ramin , Falah Masoume , Aslani Ali , Zhong Xiao Yan , Saleki Ahmad
Published: May 2009

ABSTRACT: Complete androgen insensitivity syndrome is an X‐linked inherited disorder caused by mutations in the androgen receptor (AR) gene. Using polymerase chain reaction single‐strand DNA conformational polymorphism and DNA sequencing, we identified a novel nonsense mutation in exon 1 of the AR gene in 2 Iranian brothers with complete androgen insensitivity syndrome. Despite a normal 46,XY karyotype, testes, and normal to elevated plasma levels of testosterone, they were born with female external genitalia and phenotype. This new mutation, a T‐to‐A transversion in exon 1, causes amino acid change of tyrosine (TAT) to ochre stop codon (TAA) at position 514 of the AR polypeptide. The Y514X mutation is located in a region that is normally important for the formation and function of the hormone receptor complex. We conclude that the novel Y514X mutation in the androgen receptor is the cause of complete androgen insensitivity syndrome in this family.
Is Obesity Correlated With Sexual Function in Young Men?
Authors: Tsao Chih‐Wei , Hsu Chien‐Yeh , Chou Yu‐Ching , Wu Sheng‐Tang , Sun Guang‐Huan , Yu Dah‐Shyong , Fan Pao‐Luo , Chen Hong‐I , Chang Sun‐Yran , Cha Tai‐Lung
Published: May 2009

ABSTRACT: The study investigated the correlation between obesity and sexual function in young men. It was a cross‐sectional study in an unselected consecutive sample of military men aged less than 28 years old attending to the Navy Recruit Training Center. There were 772 subjects included in the study, excluding subjects with comorbidities and subjects who had not engaged in sexual intercourse. All men underwent a detailed health examination, including physical assessment and taking of medical history. Obesity was assessed by anthropometric means, including body mass index, waist circumference (WC), and waist‐to‐hip ratio. Subjects were categorized into 4 groups by increasing order according to each anthropometric indicator (quartile method). Clinical sexual function was evaluated with the International Index of Erectile Function −5 (IIEF‐5) scale score. There was no statistical difference in IIEF‐5 score between smoking and nonsmoking groups (t test, P = .422). According to analysis of variance, only the anthropometric indicator WC showed a statistically significant correlation with IIEF‐5 severity (P = .032). A possible explanation was that the systemic effects of obesity and smoking would take place while combined with the process of aging.
Preparation and Characterization of Prostate Cell Lines for Functional Cloning Studies to Identify Regulators of Apoptosis
Authors: Pickard Mark R. , Darling David , Farzaneh Farzin , Williams Gwyn T.
Published: May 2009

ABSTRACT: Because apoptotic evasion is a central feature of prostate cancer, there is an urgent need for increased understanding of the key regulatory molecules that control the life/death decision of prostate cells. Functional expression cloning permits the isolation of genes that control the rate‐limiting steps of cell death and offers a possible solution to this problem. This technique requires the availability of prostate cells that meet several stringent requirements. Therefore, the main objective was to obtain prostate cell clones that undergo cell death with minimal survival of spontaneously resistant cells and that can be infected at a high efficiency with viral vectors. Initial characterization of 5 prostate cell lines with a range of apoptotic inducers revealed cell line—dependent and treatment‐dependent effects. In general, the colony‐forming ability of nontumorigenic PNT2C2 cells showed the highest sensitivity to most chemical agents and ultraviolet (UV) irradiation, whereas the metastases‐derived cell lines, LNCaP and PC‐3, showed resistance to UV and etoposide, respectively. Clones of PNT2C2, 22Rv1, and PC‐3 were produced, which displayed heterogeneous responses to UV irradiation. Further characterization of UV‐sensitive clones revealed at least 1 clone per cell line with high sensitivity (mean clonogenic survival ≤0.02% control cells) to 3 or more apoptotic inducers. These clones could be infected at a high efficiency (>90%) with a lentiviral vector. In conclusion, we have isolated clones of nontumorigenic prostate cells (PNT2C2), androgen‐sensitive prostate cancer cells (22Rv1), and androgen‐independent, metastatic prostate cancer cells (PC‐3), which are suitable as host cells for functional cloning studies to address cell death control mechanisms in the prostate during cancer progression.
Effect of Egg Yolk on Cryopreservation of Rhesus Monkey Ejaculated and Epididymal Sperm
Authors: Dong Qiaoxiang , Vandevoort Catherine A.
Published: May 2009

ABSTRACT: Sperm cryopreservation in rhesus monkeys has not been successful when applied in standard, intravaginal artificial insemination; thus, there is a need for substantial improvement in current cryopreservation protocols. The present study was part of our systematic approach to optimize the cryopreservation procedure. Specifically, we tested whether modification of the concentration of egg yolk, the dilution method, and the time delay between ejaculation and adding egg yolk would result in significant improvement of postthaw motility for ejaculated sperm. We also tested the effects of presence and absence of egg yolk on cryopreservation of ejaculated and epididymal sperm. Our findings indicated that the concentration of egg yolk (2%–50%, vol/vol), the dilution method, and the delay (1–5 hours) in addition of egg yolk had no significant effect on postthaw motility of ejaculated rhesus monkey sperm. The presence of egg yolk yielded significantly higher motility after thawing than samples without egg yolk for ejaculated and epididymal sperm. The present study suggests that as long as egg yolk is present in the extender, details such as the amount of egg yolk, as well as when and how to add the egg yolk, have little impact on the ultimate freezing outcomes for ejaculated rhesus monkey sperm. We also discuss the possible mechanism of the protective role of egg yolk in sperm cryopreservation.
Urinary Metabolites of Di(2‐ethylhexyl) Phthalate Are Associated With Decreased Steroid Hormone Levels in Adult Men
Authors: Meeker John D. , Calafat Antonia M. , Hauser Russ
Published: May 2009

ABSTRACT: Experimental animal studies have demonstrated that exposure to some phthalates may be associated with altered endocrine function and adverse effects on male reproductive development and function, but human studies are limited. In the present study, urine and serum samples were collected from 425 men recruited through a US infertility clinic. Urinary concentrations of mono(2‐ethylhexyl) phthalate (MEHP), the hydrolytic metabolite of di(2‐ethylhexyl) phthalate (DEHP), and other phthalate monoester metabolites were measured, along with serum levels of testosterone, estradiol, sex hormone—binding globulin (SHBG), follicle‐stimulating hormone, luteinizing hormone, inhibin B, and prolactin. Two oxidized urinary metabolites of DEHP were also measured in urine from 221 of the men. In multiple regression models adjusted for potential confounders, MEHP was inversely associated with testosterone, estradiol, and free androgen index (FAI). An interquartile range increase in MEHP was associated with 3.7% (95% confidence interval [CI], −6.8% to −0.5%) and 6.8% (95% CI, −11.2% to −2.4%) declines in testosterone and estradiol, respectively, relative to the population median hormone levels. There was limited evidence for effect modification of the inverse association between MEHP and FAI by the proportion of DEHP metabolites in the urine measured as MEHP (MEHP%), which is considered a phenotypic marker of less efficient metabolism of DEHP to its oxidized metabolites. Finally, the ratio of testosterone to estradiol was positively associated with MEHP (P = .07) and MEHP% (P = .007), suggesting potential relationships with aromatase suppression. In conclusion, these results suggest that urinary metabolites of DEHP are inversely associated with circulating steroid hormone levels in adult men. However, additional research is needed to confirm these findings.
Increased Aggressiveness of Human Prostate PC‐3 Tumor Cells Expressing Cell Surface Localized Membrane Type‐1 Matrix Metalloproteinase (MT1‐MMP)
Authors: Wang Xing , Wilson Michael J. , Slaton Joel W. , Sinha Akhouri A. , Ewing Stephen L. , Pei Duanqing
Published: May 2009

ABSTRACT: Membrane type‐1 matrix metalloproteinase (MT1‐MMP) is a multidomain transmembrane endopeptidase with a major role in physiological and pathological processes through proteolysis of extracellular matrix and other pericellular proteins. We examined cell surface function of MT1‐MMP in PC‐3 human prostate tumor cells selected for metastasis in nude mice (PC‐3‐LN4), or transfected with the full‐length wild‐type (WT) MT1‐MMP or with the mutant form lacking the cytoplasmic tail (ΔC‐MT1‐MMP). Enhanced cell surface MT1‐MMP was determined by fluorescence‐activated cell sorting analysis and evidenced mechanistically by increased activation of proMMP‐2 and invasion into type‐I collagen gels. PC‐3 cells overexpressing MT1‐MMP grew faster than mock‐transfected control cells subcutaneously in nude mice. MT1‐MMP localized in caveolae, as judged by immunofluorescence microscopy and sucrose‐gradient, detergent‐resistant cell fractionation. ΔC‐MT1‐MMP was strongly associated with caveolae, whereas the WT form was present in both caveolae and noncaveolae fractions. The role of plasma membrane MT1‐MMP was supported by localization of MT1‐MMP by immunofluorescence microscopy at the cell surface of tumor cells in primary prostate cancers. Increased plasma membrane localization of MT1‐MMP, either in caveolae or in other lipid raft structures, is a mechanism to localize this proteinase in contact with extracellular matrix and other pericellular proteins, the cleavage of which can facilitate prostate cancer cell invasion and metastasis.
Androgen Receptor in Sertoli Cells Is Not Required for Testosterone‐Induced Suppression of Spermatogenesis, but Contributes to Sertoli Cell Organization in Utp14bjsd Mice
Authors: Wang Gensheng , Weng Connie C. Y. , Shao Shan H. , Zhou Wei , de Gendt Karel , Braun Robert E. , Verhoeven Guido , Meistrich Marvin L.
Published: May 2009

ABSTRACT: Testosterone acting through the androgen receptor (AR) maintains the arrest of spermatogonial differentiation in juvenile spermatogonial depletion (jsd mutation in the Utp14b gene) mutant adult male mice. It is not known which of the somatic cell types expressing AR mediates this inhibition. To determine whether Sertoli cells are responsible, we selectively eliminated AR in Sertoli cells in jsd mice containing a floxed‐Ar gene and an anti‐Müllerian hormone–Cre transgene. In these Sertoli AR‐knockout (SCARKO)‐jsd mice, spermatogonial differentiation did not recover. However, the normal organization of Sertoli cell nuclei was drastically disrupted in SCARKO‐jsd mice compared with SCARKO or jsd mice. In addition, the extent of ectoplasmic specializations was reduced; tight junctions were not found; vinculin, an anchoring protein found in ectoplasmic specializations, became uniformly distributed in the cytoplasm; and the adult Sertoli cells showed excess heterochromatin subjacent to their nuclear envelope. Despite the abnormalities in Sertoli cells in SCARKO‐jsd mice, global suppression of testosterone action and levels was still effective in restoring the differentiated germ cells, and this was accompanied by an improved arrangement of Sertoli cell nuclei. We conclude that Sertoli cells are not targets for the testosterone‐mediated inhibition of spermatogonial differentiation in jsd mice, and that both AR in Sertoli cells and the presence of differentiated germ cells contribute to maintaining the organization of Sertoli cells within the seminiferous tubules.
Buyer Power in U.K. Food Retailing: A 'First-Pass' Test
Authors: Lloyd Tim , McCorriston Steve , Morgan Wyn , Rayner Anthony , Weldegebriel Habtu
Published: May 2009

The potential existence of buyer power in U.K. food retailing has attracted the scrutiny of the U.K.'s anti-trust authorities, culminating in the second of two comprehensive regulatory inquiries in recent years. Such inquiries are authoritative but correspondingly time-consuming and costly. Moreover, detection of buyer power has been dogged by the paucity of reliable evidence of its existence. In this paper, we present a simple theoretical model of oligopsony which delivers quasi-reduced form retailer-producer pricing equations with which the null of perfect competition can be tested using readily available market data. Using a cointegrated vector autoregression, we find empirical results that show the null of perfect competition can be rejected in seven of the nine food products investigated. Though not conclusive on the existence of buyer power, the proposed test offers a means via which the behaviour of the retail-producer price spread is consistent with it. At the very least, it can corroborate the concerns of the anti-trust authorities as to whether buyer power is potentially one source of concern.
M. Heidegger: Metaphysical character of technical scientific civilisation
Authors: Savic Mico
Published: May 2009

In this paper, author deals with Heidegger's account of the modern age as the epoch based on Western metaphysics. In the first part of the paper, he shows that, according to Heidegger, modern interpretation of the reality as the world picture, is essentially determined by Descartes' philosophy. Then, author exposes Heidegger's interpretation of the turn which already took place in Plato's metaphysics and which made possible Descartes' metaphysics and modern epoch. In the second part of the paper, author explores Heidegger's interpretation of science and technology as shoots of very metaphysics. Heidegger emphasizes that the essence of technology corresponds to the essence of subjectivity and shows how the metaphysics of subjectivity subsequently finds its end in Nietzsche's metaphysics of the will to power, as the last word of Western philosophy. In the concluding part, author argues that the contemporary processes of globalization can be just understood as processes of completion of metaphysics. They can be identified as a global rule of the essence of technology. On the basis of Heidegger's vision of overcoming metaphysics, author concludes that it opens the possibility of a philosophy of finitude which points to dialogue with the Other as a way of resolving the key practical issues of the contemporary world.
Debate on sublime in the end of 18th century: Burke, Kant, Schiller
Authors: Jeremic-Molnar Dragana , Molnar Aleksandar
Published: May 2009

In the article the authors are examining three positions within the 18th Century aesthetic discussion on the sublime - Edmund Burke's, Immanuel Kant's and Friedrich Schiller's. They are also trying to reconstruct the political backgrounds of each of this theoretical positions: old regime conservatism (Burke), republican liberalism (Schiller) and romantic longing for the 'third way' (Kant). The most sophisticated and mature theory of sublime is found in Schiller's aesthetic works, especially in those following his disappointment in French Revolution, in which the relationship between sublime and paradoxes of historical violence is most thoroughly reflected.
Les réparations des vaincus, les dettes des vainqueurs: le cas de la France et du Royaume des Serbes, Croates et Slovènes/Yougoslavie
Authors: Sretenovic Stanislav
Published: May 2009

(francuski) S'appuyant sur l'analyse historique des relations entre la France et le Royaume des Serbes, Croates et Slov?nes/Yougoslavie apr?s la Premi?re Guerre mondiale, l'auteur traite de l'application des d?cisions du trait? de Versailles en mati?re ?conomique et financi?re, et montre comment elle pesa sur les relations, non seulement entre les Alli?s et leurs anciens ennemis, mais aussi entre les Alli?s eux-m?mes. Il conclut que la mise en place d'un ordre juste d?pendait de tout un ensemble de solutions concr?tes que les faiblesses du nouveau syst?me international, r?v?l?es d?s sa naissance, rendaient difficiles ? trouver. .
On the mean square of the Riemann zeta-function in short intervals
Authors: Ivic Aleksandar
Published: May 2009

It is proved that, for T? ? G = G(T)? ??T, ?T2T(I1(t+G,G)- I1(t,G))2 dt = TG ?aj logj (?T/G)+ O?(T1+? G1/2+ +T1/2?G? with some explicitly computable constants aj(a3>0)where, for fixed K ? N, Ik(t,G)= 1/?? ? ? -? |?(1/2 + it + iu)|2k e -(u/G)?du. The generalizations to the mean square of I1(t+U,G)-I1(t,G) over [T,T+H] and the estimation of the mean square of I2(t+ U,G) - I2(t,G) are also discussed.
Distance spectra and distance energies of iterated line graphs of regular graphs
Authors: Ramane H.S. , Revankar D.S. , Gutman Ivan , Walikar H.B.
Published: May 2009

The distance or D-eigenvalues of a graph G are the eigenvalues of its distance matrix. The distance or D-energy ED(G) of the graph G is the sum of the absolute values of its D-eigenvalues. Two graphs G1 and G2 are said to be D-equienergetic if ED(G1) = ED(G2). Let F1 be the 5-vertex path, F2 the graph obtained by identifying one vertex of a triangle with one end vertex of the 3-vertex path, F3 the graph obtained by identifying a vertex of a triangle with a vertex of another triangle and F4 be the graph obtained by identifying one end vertex of a 4-vertex star with a middle vertex of a 3-vertex path. In this paper we show that if G is r-regular, with diam(G)? 2, and Fi,i = 1,2,3,4, are not induced subgraphs of G, then the k-th iterated line graph Lk(G) has exactly one positive D-eigenvalue. Further, if G is r-regular, of order n, diam(G)?2, and G does not have Fi,i=1,2,3,4, as an induced subgraph, then for k ?1, ED(Lk(G)) depends solely on n and r. This result leads to the construction of non D-cospectral, D-equienergetic graphs having same number of vertices and same number of edges.
On relation between spectra of graphs and their digraph decompositions
Authors: Stevanovic Dragan , Stevanovic Sanja
Published: May 2009

A graph, consisting of undirected edges, can be represented as a sum of two digraphs, consisting of oppositely oriented directed edges. Gutman and Plath in [J. Serb. Chem. Soc. 66 (2001), 237-241] showed that for annulenes, the eigenvalue spectrum of the graph is equal to the sum of the eigenvalue spectra of respective two digraphs. Here we exhibit a number of other graphs with this property.
Distribution groups
Authors: Kostic Marko
Published: May 2009

We introduce distribution groups and [B0,... ,Bn,C0,...,Cn-1]- groups with not necessarily densely defined generators and systematically analyze relations between them.
Effect of zircon on sintering, composition and microstructure of magnesia powders
Authors: Peng C. , Li N. , Han B.
Published: May 2009

The effects of zircon on sintering, composition and microstructure of fused magnesia powders were studied by XRD, SEM and EDAX. With the increase of zircon content up to 6 wt%, the strength of sintered samples increased but the apparent porosity decreased. 6 wt% is an appropriate content of zircon to possess better properties of samples, and in this case the samples have a dense microstructure and lower content of glass phase. The presence of a liquid phase resulting from zircon addition is the main reason to improve sintering of magnesia powders.
Features of formation of composite ceramics from SiC-Si-Mo at high pressure
Authors: Vlasova M. , Bykov A. , Rosales I. , Kakazey M. , Guardian R.
Published: May 2009

SiC-based composite ceramics were investigated by X-ray diffraction, electron microscopy and electron-probe X-ray microanalysis. It is established that, depending on the composition of the initial powder mixtures, at T = 1500-1800?C and P = 4 GPa, different types of composite ceramics formed. Ceramics obtained from mixtures with CSiC ? 50 wt. % contains SiC, Si, and Mo. Ceramics on the base of SiC-MoSi2 was obtained from mixtures with CSiC < 50 wt.%.
Characterization of anatase TiO2 nanopowder by variable-temperature Raman spectroscopy
Authors: Scepanovic Maja , Grujic-Brojcin M. , Dohcevic-Mitrovic Z.D. , Popovic Z.V.
Published: May 2009

Raman spectroscopy has been used for characterization of commercial nanosized TiO2 powder with declared grain size of 5 nm. The Raman spectra measured in Stokes and anti-Stokes regime confirm the anatase phase of TiO2 powder in temperature range 25-1173K. It is shown that phonon-confinement (due to small grain size) and nonstoichiometry (caused by laser irradiation in vacuum) have a great influence on blueshift and broadening of the main Eg Raman mode at low temperatures, while the influence of the strong anharmonic effect becomes dominant at higher temperatures. The phonon confinement effect decreases due to the crystallite growth at temperatures above 673K.
The inhomogeneous quantum invariance group of the multi-dimensional q-deformed boson algebra
Authors: Altıntaş Azmi , Arık Metin , Arıkan Ali
Published: May 2009

In this study we introduce a multi-dimensional q-deformed boson algebra and calculate its inhomogeneous invariance quantum group.
Characterization of recombinant antibodies for detection of TNT and its derivatives
Authors: Simonoviíc Mladen , Milosević-Zlatanović Svetlana , Milosavić Nenad , Vrvić Miroslav , Simonović Branislav
Published: May 2009

Diverse recombinant immunoreagents specific for TNT-derivatives were tested in different assay forms in order to analyze their specificity and sensitivity. Performance of immunoassays was based on TNP-protein conjugates immobilization on a solid surface. In this work, the detection limit for TNT-analog TNP-Tris was 250 fmol or 87 pg mL−1 (87 ppt), which represents the most sensitive assay published until now, regarding the detection of recombinant antibodies.
The Saxo-Danubian Granite Belt: magmatic response to post-collisional delamination of mantle lithosphere below the southwestern sector of the Bohemian Massif (Variscan orogen)
Authors: Finger Fritz , Gerdes Axel , René Miloš , Riegler Gudrun
Published: May 2009

The Saxo-Danubian Granite Belt: magmatic response to post-collisional delamination of mantle lithosphere below the southwestern sector of the Bohemian Massif (Variscan orogen)

On the basis of the synchronicity of geochronological data and the similarity of granite types, it is proposed that the mid-Carboniferous Fichtelgebirge/Erzgebirge Batholith in the Saxothuringian Zone of the central European Variscan Fold Belt and the South Bohemian Batholith in the Moldanubian Zone (including the intervening Oberpfalz and Bavarian Forest granite areas) belong to one coherent and cogenetic, ca. 400 km long plutonic megastructure. Unlike older (syn-collisional) plutonic structures in the Bohemian Massif, this Saxo-Danubian Granite Belt (nov. nom.) has developed discordant to the Devonian/Early Carboniferous collision-related tectonic architecture of the Bohemian Massif. It is argued that the Saxo-Danubian Granite Belt formed in response to a post-collisional detachment of lithospheric mantle below the south-western sector of the Bohemian Massif.
The Brodno section — a potential regional stratotype of the Jurassic/Cretaceous boundary (Western Carpathians)
Authors: Michalík Jozef , Reháková Daniela , Halásová Eva , Lintnerová Otília
Published: May 2009

The Brodno section — a potential regional stratotype of the Jurassic/Cretaceous boundary (Western Carpathians)

Compared to coeval successions from the Carpathians, the continuous Jurassic-Cretaceous (J/K) pelagic limestone succession of the Brodno section offers the best possibility to document the J/K passage in a wide area. This section comprises a complete calpionellid, and nannofossil stratigraphic record, that supports the older paleomagnetic data. Moreover, the sequence stratigraphy and stable isotope (δ18O, δ13C) data gave important results, too, enabling comparison with known key sections from the Mediterranean Tethys area.
Ichnology of the Cretaceous Oceanic Red Beds (Outer Western Carpathians, Czech Republic)
Authors: Mikuláš Radek , Skupien Petr , Bubík Miroslav , Vašíček Zdeněk
Published: May 2009

Ichnology of the Cretaceous Oceanic Red Beds (Outer Western Carpathians, Czech Republic)

Large differences in the intensity and overall character of bioturbational structures were found in five facies containing hemipelagic red beds. Red beds (CORB) of the Godula facies of the Silesian Unit and their equivalents (mostly not red) in the Kelč facies of the Silesian Unit and the CORB in the non-calcareous sediments of the Rača Unit display a very low degree of bioturbation. The CORB facies of the Rača Unit, containing calcareous intercalations, displays a very high degree of bioturbation as expressed by a high ichnofabric index. They contain trace fossilsChondrites, Zoophycos, Planolites, Thalassinoides, Palaeophycus, TeichichnusandPhycosiphon.The supply of food obviously acted as the controlling factor. The "calcareous" facies of the CORB of the Rača Unit has a considerably higher proportion of sand-dominated interbeds and also carbonates than the non-calcareous facies. This (especially the presence of carbonates) suggests a relative proximity of food-rich environments and an easy transport of nutrition-rich substrate by turbidite currents into the basin directly, not only by periodical fall-out of dead plankton (which is probably responsible for the rhythmicity of poor colonization horizons in weakly bioturbated units).
Clay minerals from Weichselian glaciolimnic sediments of the Sępopolska Plain (NE Poland)
Authors: Dlugosz Jacek , Orzechowski Miroslaw , Kobierski Miroslaw , Smolczynski Slawomir , Zamorski Ryszard
Published: May 2009

Clay minerals from Weichselian glaciolimnic sediments of the Sępopolska Plain (NE Poland)

Glaciolimnic deposits sampled from three sedimentation reservoirs located on the Sępopolska Plain (northeastern Poland) were investigated. The material under study was deposited in the recession phase of the Pomeranian phase of Vistula (Weichselian) glaciation. The clay fraction was separated by centrifugation after preparation according to Jackson. Mineralogical investigations were done by X-ray diffraction. The analysed deposits had a similar complex composition of clay minerals. The main components were illites mixed with the illite/smectite mineral with percentages < 10 % S. Another part were minerals of the illite/smectite type which had differentiated content of smectite layers (mainly 80-90 % S). There were also chlorite minerals, probably as mixed layer minerals of the chlorite/vermiculite type or HIV with a negligible amount of chlorite layers. The results indicated that all the deposits were of the same age as well as similar deposited material and the samples are different from typical Pomeranian till and typical limnic material of the same age. Small differences observed among the deposits of specific sedimentation reservoirs were probably the result of later processes.
Kali Gandaki ‘A’ Hydroelectric Project in Environmental Perspectives
Authors: Thanju Rajendra P.
Published: May 2009

Hydropower is one of the cleanest, renewable and environmentally benign sources of energy. Nepal is blessed with immense source of water resources and huge hydropower potential. The Kali Gandaki ‘A’ (KGA) Hydroelectric Project is the largest hydropower project constructed so far in Nepal. The project is a daily pondage type scheme with an installed capacity of 144 MW.

The KGA is one of the first largest hydropower projects that has been well studied environmentally and socially in the pre-project, construction and operation stages. A full team of multi-disciplinary professionals was involved during the construction phase to monitor environmental impacts and compliance with contract clauses, and to implement the mitigation measures.

Implementation of KGA in what was once considered as a remote area, has resulted in multifold beneficial impacts to the local community. Improvement of public infrastructure, enhanced educational facilities and employment of local populations, including affected families during project construction and operation phase, have enhanced the quality of rural lives. The KGA operation has contributed significantly to Nepal’s power system and has boosted the economic development of the country.

Key words: Hydropower; environmental monitoring; impacts; mitigation; resettlement; Nepal

Hydro Nepal: Journal of Water, Energy and Environment Vol. I No. 1, 2007 pp. 15-21
IRR: An Operational Risks Reduction Model for Population Resettlement
Authors: Cernea Michael M.
Published: May 2009

Abstract. The construction of hydropower dams and of other types of projects must plan also for the relocation of populations living in the project area, a process fraught with risks and difficulties. This paper describes an analytical, diagnostic, predictive, and planning tool for such projects, developed by the author, named the Impoverishment Risks and Reconstruction (IRR) model. Derived from knowledge and lessons of many previous projects, this model can serve as predictor of risks and problems that will be encountered in forthcoming projects, and be used as guide in applying strategies to counter, overcome or mitigate these risks. Among these are the eight basic risks of impoverishment faced during displacement and resettlement, such as: 1) Landlessness; 2) Joblessness; 3) Homelessness; 4) Marginalization; 5) Food insecurity; 6) Increased morbidity and mortality; 7) Loss of access to common property resources; and 8) Community Disarticulation. Further, the counter-risks strategies and measures are ‘modeled’, to help early risk-elimination or risk-reduction actions.

The IRR Model is being used internationally. It was applied also in studies for Nepal’s Kali Gandaki project to monitor implementation and impacts, to explore what measures and management strategies can be employed against the common risks in resettlement, and to assist those affected in overcoming land or house loss and in deriving benefits from the project.

Key words: Risk model, resettlement, displacement, impoverishment, reconstruction

Hydro Nepal: Journal of Water, Energy and Environment Vol. I, Issue No. 1 (2007) pp. 35-39
Legal and Policy Environment for Private Sector Participation
Authors: Upadhyay Anup Kumar
Published: May 2009

Not Available
Underground Space for Infrastructure Development and Engineering Geological Challenges in Tunneling in the Himalayas
Authors: Panthi Krishna Kanta
Published: May 2009

Being topographically steep and consisting of many rivers originating from the glaciers of the Himalaya, Nepal is gifted in water resources. As a developing country, Nepal needs to accelerate to develop its crucial infrastructures for the economic prosperity of the nation. This is achievable by developing the enormous hydropower potential available, making short and efficient roads through the steep mountain topography, extracting mines for various purposes, and providing cost effective solutions for the storage facilities. These developments are not possible unless tunnels and underground caverns are used.

Due to tectonic activity, however, the rock mass in Nepal and across the Himalayan region is somewhat different in their engineering behaviour. These differences in mechanical behaviour are mainly caused by a high degree of folding, faulting, shearing, fracturing and deep weathering. As a result, severe instability problems associated with this complex geological setup have to be faced during tunnelling. This is the major challenge to be addressed in a scientific manner in order to make tunnel option more cost effective, feasible and safer.

This paper delineates the possible areas where tunnels and underground caverns are needed and may play an important role in the socio-economic development of the nation, discusses the major geological challenges faced while tunnelling, and briefly describes methodologies to be used for analysing geological uncertainties.

Key words: Himalayan geology, tunnelling, Nepal

Hydro Nepal: Journal of Water, Energy and Environment Vol. I, Issue No. 1 (2007) pp. 43-49