Carbon dioxide reforming of ethanol over Ni/Y(2)O(3)-ZrO(2) catalysts

Supported nickel catalysts of composition Ni/Y(2)O(3)-ZrO(2) were synthesized in one step by the polymerization method and compared with a nickel catalyst prepared by wet impregnation. Stronger interactions were observed in the formed catalysts between NiO species and the oxygen vacancies of the Y(2)O(3)-ZrO(2) in the catalysts made by polymerization, and these were attributed to less agglomeration of the NiO during the synthesis of the catalysts in one step. The dry reforming of ethanol was catalyzed with a maximum CO(2) conversion of 61% on the 5NiYZ catalyst at 800 degrees C, representing a better response than for the catalyst of the same composition prepared by wet impregnation. (C) 2009 Published by Elsevier B.V.

What do they expect? : A case study on the work expectations of the working German Generation Y

Purpose – The purpose of this paper is to identify the expectations of the workingGerman Generation Y regarding its current work and employer. As a result, the mainelements which could be considered by companies to retain the Generation Y inGermany will be pointed out and discussed.Design/methodology/approach – Semi-structured interviews were used in order toexplore the work expectations of this young generation within a German company. Anon-probability and purposive sample was used and six respondents part of theGeneration Y and working in the same company were interviewed. Furthermore, aseventh interview was conducted with the HMR of the company.Findings – Several findings are consistent with previous results of Gen Y from othernationalities than Germany such as the importance of varied tasks, opportunities forself-development, responsibilities and a pleasant working atmosphere. However,differences were found in particular regarding the importance of the work-life balanceand new expectations such as trust, autonomy and internationality have been broughtto light. Furthermore, several findings are also consistent with other studies aboutemployee retention, commitment and job satisfaction.Originality/value – This research extended previous studies of the expectations of theGeneration Y by providing firstly findings for Germany, a country where such studieshave not been conducted yet and secondly by focusing on the Generation Y who isalready working and therefore not studying anymore.

Virulence characteristics and epidemiology of Yersinia enterocolitica and Yersiniae other than Y-pseudotuberculosis and Y-pestis isolated from water and sewage

Aims: To determine the species, bio-sero-phagetypes, antimicrobial drug resistance and also the pathogenic potential of 144 strains of Yersinia spp. isolated from water sources and sewage in Brazil.Methods and Results: the 144 Yersinia strains were characterized biochemically, serologically and had their antibiotic resistance and phenotypic virulence markers determined by microbiological and serological standard techniques. The Y. enterocolitica strains related to human diseases were also tested for the presence of virulence genes, by the PCR technique. The isolates were classified as Y. enterocolitica, Y. intermedia, Y. frederiksenii, Y. kristensenii and Yersinia biochemically atypical. The 144 isolates belonged to various bio-serogroups. Half of the strains showed resistance to three or more drugs. The Y. enterocolitica strains related to human diseases exhibited phenotypic virulence characteristics and virulence genes.Conclusions: Water from various sources and sewage are contaminated with Yersinia spp. in Brasil. Among these bacteria, virulent strains of Y. enterocolitica were found, with biotypes and serogroups related to human diseases.Significance and Impact of the Study: This is the first documented description of the occurrence of pathogenic Y. enterocolitica in water sources and sewage in Brazil. The occurrence of virulence strains of Y. enterocolitica shows that the environment is a potential source of human infection by this species in this country.

Comparative RH Maps of the River Buffalo and Bovine Y Chromosomes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Bonding of Y-TZP to Dentin: Effects of Y-TZP Surface Conditioning, Resin Cement Type, and Aging

Purpose: To evaluate the effects of two surface treatments, aging, and two resin cements on shear bond strength between dentin and yttrium-stabilized tetragonal zirconia polycrystal ceramic (Y-TZP).Materials and Methods: Eighty human molars were embedded in acrylic resin and sectioned 3 mm below the occlusal plane. These teeth and 80 cylindrical Y-TZP specimens (height, 4 mm; diameter, 3.4 mm) were divided into eight groups (n=10) using the following factors: Y-TZP surface treatment (Vi: low-fusing porcelain [vitrification] + hydrofluoric acid etching + silanization or Si: tribochemical silicatization); cementation strategies (PF: Pan avia or CC: Clearfil); and storage (nonaging or aging). Bonding surfaces of 40 Y-TZP specimens received Vi treatment, and the rest received Si treatment. Half of the ceramic-tooth assemblies were cemented with Panavia, the rest with Clearfil. Shear tests were executed using 0.4-mm-thick wire at 0.5 mm/min. Data were analyzed by three-way analysis of variance and Tukey test (alpha=0.05). Fractures were analyzed.Results: Y-TZP surface treatments did not affect bond strength (p=0.762, Vi = Si), while resin cements (p<0.001, Panavia > Clearfil) and aging (p=0.006, nonaging > aging) showed a significant effect. Most failures were in adhesive at dentin-cement interfaces; no failure occurred between zirconia and cement.Conclusion: When Y-TZP ceramic is bonded to dentin, the weakest interface is that between dentin and resin cement. The resin cement/Y-TZP interface was less susceptible to failures, owing to Y-TZP surface treatments.

Low frequency of Y anomaly detected in Australian Brahman cow-herds

Indicine cattle have lower reproductive performance in comparison to taurine. A chromosomal anomaly characterized by the presence Y markers in females was reported and associated with infertility in cattle. The aim of this study was to investigate the occurrence of the anomaly in Brahman cows. Brahman cows (n = 929) were genotyped for a Y chromosome specific region using real time-PCR. Only six out of 929 cows had the anomaly (0.6%). The anomaly frequency was much lower in Brahman cows than in the crossbred population, in which it was first detected. It also seems that the anomaly doesn't affect pregnancy in the population. Due to the low frequency, association analyses couldn't be executed. Further, SNP signal of the pseudoautosomal boundary region of the Y chromosome was investigated using HD SNP chip. Pooled DNA of non-pregnant and pregnant cows were compared and no difference in SNP allele frequency was observed. Results suggest that the anomaly had a very low frequency in this Australian Brahman population and had no effect on reproduction. Further studies comparing pregnant cows and cows that failed to conceive should be executed after better assembly and annotation of the Y chromosome in cattle.

Variable patterns of Y chromosome homology in Akodontini rodents (Sigmodontinae): a phylogenetic signal revealed by chromosome painting

The Akodontini is the second most speciose tribe of sigmodontine rodents, one of the most diverse groups of neotropical mammals. Molecular phylogenetic analyses are discordant regarding the interrelationships of genera, with low support for some clades. However, two clades are concordant, one (clade A) with Akodon sensu strictu (excluding Akodon serrensis), "Akodon" serrensis, Bibimys, Deltamys, Juscelinomys, Necromys, Oxymycterus, Podoxymys, Thalpomys and Thaptomys, and another (clade B) with Blarinomys, Brucepattersonius, Kunsia, Lenoxus and Scapteromys. Here, we present chromosome painting using Akodon paranaensis (APA) Y paint, after suppression of simple repetitive sequences, on ten Akodontini genera. Partial Y chromosome homology, in addition to the homology already reported on the Akodon genus, was detected on the Y chromosomes of "A." serrensis, Thaptomys, Deltamys, Necromys and Thalpomys and on Y and X chromosomes in Oxymycterus. In Blarinomys, Brucepattersonius, Scapteromys and Kunsia, no APA Y signal was observed using different hybridization conditions; APA X paint gave positive signals only on the X chromosome in all genera. The Y chromosome homology was variable in size and positioning among the species studied as follow: (1) whole acrocentric Y chromosome in Akodon and "A." serrensis, (2) Yp and pericentromeric region in submetacentric Y of Necromys and Thaptomys, (3) pericentromeric region in acrocentric Y of Deltamys, (4) distal Yq in the acrocentric Y chromosome of Thalpomys and (5) proximal Yq in the acrocentric Y and Xp in the basal clade A genus Oxymycterus. The results suggest that the homology involves pairing (pseudoautosomal) and additional regions that have undergone rearrangement during divergence. The widespread Y homology represents a phylogenetic signal in Akodontini that provides additional evidence supporting the monophyly of clade A. The findings also raise questions about the evolution of the pseudoautosomal region observed in Oxymycterus. The Y chromosomes of these closely related species seem to have undergone dynamic rearrangements, including restructuring and reduction of homologous segments. Furthermore, the changes observed may indicate progressive attrition of the Y chromosome in more distantly related species.

Residual stresses in Y-TZP crowns due to changes in the thermal contraction coefficient of veneers

Objective. To test the hypothesis that the difference in the coefficient of thermal contraction of the veneering porcelain above (˛liquid) and below (˛solid) its Tg plays an important role in stress development during a fast cooling protocol of Y-TZP crowns. Methods. Three-dimensional finite element models of veneered Y-TZP crowns were developed. Heat transfer analyses were conducted with two cooling protocols: slow (group A) and fast (groups B–F). Calculated temperatures as a function of time were used to determine the thermal stresses. Porcelain ˛solid was kept constant while its ˛liquid was varied, creating different ˛/˛solid conditions: 0, 1, 1.5, 2 and 3 (groups B–F, respectively). Maximum ( 1) and minimum ( 3) residual principal stress distributions in the porcelain layer were compared. Results. For the slowly cooled crown, positive 1 were observed in the porcelain, orientated perpendicular to the core–veneer interface (“radial” orientation). Simultaneously, negative 3 were observed within the porcelain, mostly in a hoop orientation (“hoop–arch”). For rapidly cooled crowns, stress patterns varied depending on ˛/˛solid ratios. For groups B and C, the patterns were similar to those found in group A for 1 (“radial”) and 3 (“hoop–arch”). For groups D–F, stress distribution changed significantly, with 1 forming a “hoop-arch” pattern while 3 developed a “radial” pattern. Significance. Hoop tensile stresses generated in the veneering layer during fast cooling protocols due to porcelain high ˛/˛solid ratio will facilitate flaw propagation from the surface toward the core, which negatively affects the potential clinical longevity of a crown.

[Radiation exposure in (90)Y-Zevalin therapy: results of a prospective multicentre trial]

AIM of this study was the assessment of the radiation exposure from preparation and application of (90)Y-Zevalin, the measurement of the dose rate at the patient, the exposure of family members as well as the determination of the activity concentration in urine of patients. METHODS: Overall data from 31 therapeutic administrations carried out in four institutions were evaluated. During preparation and application of (90)Y-Zevalin the finger exposures of radiochemists, technicians, and physicians were measured. The dose rate of the patient was measured immediately after radioimmunotherapy. In patients treated in a nuclear medicine therapy unit, urine was collected over a two day period and the corresponding activity was determined. Family members of outpatients were asked to wear a dosimeter over a seven day period. RESULTS: During the preparation we found a maximum skin dose of 6 mSv at the average, and during application of 3 mSv, respectively. After administration of (90)Y the dose rate was 0.4 +/- 0.1 microSv/h at 2 m distance. Urine measurements yielded a cumulated 24 h excretion of 3.9 +/- 1.4% and 4.4 +/- 1.4% within 48 h, respectively, that is equivalent to 43 +/- 18 and 50 +/- 20 MBq of (90)Y, respectively. Family members received a radiation exposure of 40 +/- 14 microSv over seven days. CONCLUSION: During preparation and application of (90)Y-Zevalin appropriate radiation shielding is necessary. For family members as well as nursing staff no additional special radiation protection measures beyond those being common for other nuclear medicine procedures are necessary.

Expresiones políticas y movilización popular en los pueblos de la campañade Buenos Aires : La Guardia de Luján y el Sitio de Lagos (1852-1854)

En este artículo se abordará la problemática transición política producida en la provincia de Buenos Aires luego de la batalla de Caseros en febrero de 1852 y el impacto que generó en la campaña. Partimos del siguiente argumento: la intervención política de los habitantes rurales y el grado de dependencia/independencia de sus reclamos se explica en gran medida a través del entramado de relaciones de poder (complejo y cambiante) que se construyó en cada pueblo. En primera instancia, la atención estará puesta en las diferentes expresiones políticas que se manifestaron en el vecindario de la Guardia de Luján durante el rosismo y las repercusiones del día después. Luego, se estudiará el pronunciamiento del General Hilario Lagos del 1º de diciembre de 1852 y la participación del vecindario. Por último, se reseñaran las repercusiones locales producto del derrocamiento de Juan Manuel de Rosas

Expresiones políticas y movilización popular en los pueblos de la campañade Buenos Aires : La Guardia de Luján y el Sitio de Lagos (1852-1854)

En este artículo se abordará la problemática transición política producida en la provincia de Buenos Aires luego de la batalla de Caseros en febrero de 1852 y el impacto que generó en la campaña. Partimos del siguiente argumento: la intervención política de los habitantes rurales y el grado de dependencia/independencia de sus reclamos se explica en gran medida a través del entramado de relaciones de poder (complejo y cambiante) que se construyó en cada pueblo. En primera instancia, la atención estará puesta en las diferentes expresiones políticas que se manifestaron en el vecindario de la Guardia de Luján durante el rosismo y las repercusiones del día después. Luego, se estudiará el pronunciamiento del General Hilario Lagos del 1º de diciembre de 1852 y la participación del vecindario. Por último, se reseñaran las repercusiones locales producto del derrocamiento de Juan Manuel de Rosas

Expresiones políticas y movilización popular en los pueblos de la campañade Buenos Aires : La Guardia de Luján y el Sitio de Lagos (1852-1854)

En este artículo se abordará la problemática transición política producida en la provincia de Buenos Aires luego de la batalla de Caseros en febrero de 1852 y el impacto que generó en la campaña. Partimos del siguiente argumento: la intervención política de los habitantes rurales y el grado de dependencia/independencia de sus reclamos se explica en gran medida a través del entramado de relaciones de poder (complejo y cambiante) que se construyó en cada pueblo. En primera instancia, la atención estará puesta en las diferentes expresiones políticas que se manifestaron en el vecindario de la Guardia de Luján durante el rosismo y las repercusiones del día después. Luego, se estudiará el pronunciamiento del General Hilario Lagos del 1º de diciembre de 1852 y la participación del vecindario. Por último, se reseñaran las repercusiones locales producto del derrocamiento de Juan Manuel de Rosas

Y chromosomal fertility factors kl-2 and kl-3 of Drosophila melanogaster encode dynein heavy chain polypeptides

The molecular identity and function of the Drosophila melanogaster Y-linked fertility factors have long eluded researchers. Although the D. melanogaster genome sequence was recently completed, the fertility factors still were not identified, in part because of low cloning efficiency of heterochromatic Y sequences. Here we report a method for iterative blast searching to assemble heterochromatic genes from shotgun assemblies, and we successfully identify kl-2 and kl-3 as 1β- and γ-dynein heavy chains, respectively. Our conclusions are supported by formal genetics with X-Y translocation lines. Reverse transcription–PCR was successful in linking together unmapped sequence fragments from the whole-genome shotgun assembly, although some sequences were missing altogether from the shotgun effort and had to be generated de novo. We also found a previously undescribed Y gene, polycystine-related (PRY). The closest paralogs of kl-2, kl-3, and PRY (and also of kl-5) are autosomal and not X-linked, suggesting that the evolution of the Drosophila Y chromosome has been driven by an accumulation of male-related genes arising de novo from the autosomes.

Y chromosome polymorphism is a strong determinant of male fitness in Drosophila melanogaster

In many species, the Y (or W) chromosome carries relatively few functional genes. This observation motivates the null hypothesis that the Y will be a minor contributor to genetic variation for fitness. Previous data and theory supported the null hypothesis, but evidence presented here shows that the Y of Drosophila melanogaster is a major determinant of a male's total fitness, with standing genetic variation estimated to be 68% of that of an entire X/autosome genomic haplotype. Most Y-linked genes are expressed during spermatogenesis, and correspondingly, we found that the Y influences fitness primarily through its effect on a male's reproductive success (sperm competition and/or mating success) rather than his egg-to-adult viability. But the fitness of a Y highly depended on the genetic makeup of its bearer, reverting from high to low in different genetic backgrounds. This pattern leads to large epistatic (inconsistent among backgrounds) but no additive (consistent among backgrounds) Y-linked genetic variance for fitness. On a microevolutionary scale, the observed large epistatic variation on the Y substantially reduces heritable variation for fitness among males, and on a macroevolutionary scale, the Y produces strong selection for genomic rearrangements that move interacting genes onto the nonrecombining region of the Y.

Loss of sequences 3' to the testis-determining gene, SRY, including the Y pseudoautosomal boundary associated with partial testicular determination.

The condition termed 46,XY complete gonadal dysgenesis is characterized by a completely female phenotype and streak gonads. In contrast, subjects with 46,XY partial gonadal dysgenesis and those with embryonic testicular regression sequence usually present ambiguous genitalia and a mix of Müllerian and Wolffian structures. In 46,XY partial gonadal dysgenesis gonadal histology shows evidence of incomplete testis determination. In 46,XY embryonic testicular regression sequence there is lack of gonadal tissue on both sides. Various lines of evidence suggest that embryonic testicular regression sequence is a variant form of 46,XY gonadal dysgenesis. The sex-determining region Y chromosome gene (SRY) encodes sequences for the testis-determining factor. To date germ-line mutations in SRY have been reported in approximately 20% of subjects with 46,XY complete gonadal dysgenesis. However, no germ-line mutations of SRY have been reported in subjects with the partial forms. We studied 20 subjects who presented either 46,XY partial gonadal dysgenesis or 46,XY embryonic testicular regression sequence. We examined the SRY gene and the minimum region of Y-specific DNA known to confer a male phenotype. The SRY-open reading frame (ORF) was normal in all subjects. However a de novo interstitial deletion 3' to the SRY-ORF was found in one subject. Although it is possible that the deletion was unrelated to the subject's phenotype, we propose that the deletion was responsible for the abnormal gonadal development by diminishing expression of SRY. We suggest that the deletion resulted either in the loss of sequences necessary for normal SRY expression or in a position effect that altered SRY expression. This case provides further evidence that deletions of the Y chromosome outside the SRY-ORF can result in either complete or incomplete sex reversal.