bluuebunny/crossref_metadata_2025 huggingface dataset:
Different Molecular Constituents in Pheomelanin are Responsible for Emission, Transient Absorption and Oxygen Photoconsumption†
Authors: Ye Tong , Pawlak Anna , Sarna Tadeusz , Simon John D.
Published: January 2008

Steady‐state absorption and emission spectroscopies, oxygen activation and transient spectroscopy on a single sample of synthetic pheomelanin are compared. The absorption, emission and excitation spectra of pheomelanin depend on the molecular weight (MW) of the dissolved pigment constituents. While weakly‐depending on MW, the maximum of the emission excitation spectrum is ∼400 nm. The electron paramagnetic resonance oximetry measurements show a clear increase in oxygen uptake between 338 and 323 nm, and also reveal a local enhancement around ∼370 nm. Pump‐probe absorption spectroscopy reveals that photoexcitation of pheomelanin by UVA light generates a transient absorption peak in the visible and UV regions within the instrument response. The action spectrum for the formation of the 780 nm transient species peaks at ∼360 nm. While both transient absorption bands show the same ultrafast decay component, the 780 nm peak completely vanishes on the 10s of picosecond time scale, but the UV band shows a kinetic evolution to a subsequent intermediate. While in a similar wavelength range, the maximum of the action spectrum derived from the transient data, the emission excitation spectrum and the action spectrum for photoconsumption all differ from one another, suggesting that the chromophore responsible for each is not that same. This raises concern about comparing the results from different photochemical methodologies for melanin, which is a specific case of comparing data on systems where molecular constituents are not well defined.
Sensitivity of UV Erythemally Effective Irradiance and Daily Dose to Spatial Variability in Total Ozone
Authors: Schmalwieser Alois W. , Erbertseder Thilo , Schauberger Günther , Weihs Philipp
Published: January 2008

The total ozone column (TOC) is the most significant quantity for estimating the erythemally effective UV radiation under clear sky conditions. Uncertainties in TOC measurements and a limited spatial and temporal resolution therefore influence the quality of calculated erythemally effective radiation. The UV Index, the internationally accepted measure of the erythemally effective radiation, is used in public and the media to inform about current levels of UV radiation and builds the base for sun protection. Thus, the accuracy of the promoted values is essential. While in a preceding study we estimated the influence of measurement uncertainties, in this study we analyze the influence of spatial gaps and variability of TOC to the erythemally effective irradiance at noon and to the daily dose. The results allow defining the necessary spatial resolution of TOC values when a certain accuracy for the UV Index or for the purpose of sun protection is required. In case of the erythemally effective irradiance this study reveals that spatial gaps in TOC or the assumption of spatial invariability causes similar uncertainties independent of the geographic location. At higher latitudes the higher spatial variability of TOC counteracts the lower level of irradiance. For the daily dose gaps in TOC have an even higher impact at higher latitudes.
Variations in Chemical Composition of Clay Minerals and Magnetic Susceptibility of Hydrothermally Altered Rocks in the Hishikari Epithermal Gold Deposit, SW Kyushu, Japan
Authors: Murakami Hiroyasu
Published: January 2008

Hydrothermal alteration, involving chiefly chlorite and illite, is extensively distributed within host rocks of the Pleistocene Hishikari Lower Andesites (HLA) and the Cretaceous Shimanto Supergroup (SSG) in the underground mining area of the Hishikari epithermal gold deposit, Kagoshima, Japan. Approximately 60% of the mineable auriferous quartz‐adularia veins in the Honko vein system occur in sedimentary rocks of the SSG, whereas all the veins of the Yamada vein system occur in volcanic rocks of the HLA. Variations in the abundance and chemical composition of hydrothermal minerals and magnetic susceptibility of the hydrothermally altered rocks of the HLA and SSG were analyzed. In volcanic rocks of the HLA, hydrothermal minerals such as quartz, chlorite, adularia, illite, and pyrite replaced primary minerals. The amount of hydrothermal minerals in the volcanic rocks including chlorite, adularia, illite, and pyrite as well as the altered and/or replaced pyroxenes and plagioclase phenocrysts increases toward the veins in the Honko vein system. The vein‐centered variation in mineral assemblage is pronounced within up to 25 m from the veins in the peripheral area of the Honko vein system, whereas it is not as apparent in the Yamada vein system. The hydrothermal minerals in sandstone of the SSG occur mainly as seams less than a few millimeters thick and are sporadically observed in halos along the veins and/or the seams. The alteration halos in sandstone of the SSG are restricted to within 1 m of the veins. In the peripheral area of the Honko vein system, chlorite in volcanic rocks is characterized by increasing in Al in its tetrahedral layer and the Fe/Fe + Mg ratio toward the veins, while illite in volcanic rocks has relatively low K and a restricted range of Fe/Fe + Mg ratios. Temperature estimates derived from chlorite geothermometry rise toward the veins within the volcanic rocks. The magnetic susceptibility of tuff breccia of the HLA varies from 21 to less than 0.01 × 10−3 SI within a span of 40 m from the veins and has significant variation relative to that of andesite (27–0.06 × 10−3 SI). The variation peripheral to the Honko vein system correlates with an increase in the abundance of hematite pseudomorphs after magnetite, the percentage of adularia and chlorite with high Fe/Fe + Mg ratios, and the degree of plagioclase alteration with decreasing distance to the veins. In contrast, sedimentary rocks of the SSG maintain a consistent magnetic susceptibility across the alteration zone, within a narrow range from 0.3 to 0.2 × 10−3 SI. Magnetic susceptibility of volcanic rocks of the HLA, especially tuff breccia, could serve as an effective exploration tool for identifying altered volcanic rocks.
Gold Abundance and Stable Isotopes (H, O, S) in Hydrothermal Alteration Zones of Gasa Island (Gasado), Korea
Authors: Yoon Chung‐Han , Jung Hyoung‐Su
Published: January 2008

Geology of the Gasa Island (Gasado), Korea, consists mainly of tuffaceous rocks, rhyolite and andesitic rocks related to Cretaceous volcanic activity. These rocks are hydrothermally altered, and are classified into the following four alteration zones based on the alteration mineral assemblages: advanced argillic alteration (alunite‐pyrophyllite‐kaolinite‐pyrite); sericitic alteration (sericite‐kaolinite‐quartz); propylitic alteration (quartz‐chlorite‐carbonate‐pyrite); and silicified zones. Alunite in the advanced argillic zone occurred in two types; a massive or disseminated type and a vein type. Most of the massive or disseminated alunites are ≥50 μm in size, whereas the size of vein alunites is <20–30 μm. Alunite grain size is greater in the central part of disseminated or massive alunite, while it is smaller toward the margins. The gold content of each alteration zone is 21–2900 ppb, 15–88 ppb, 57–1730 ppb, and 2–231 ppb, respectively. The gold content of quartz veins developed in the alteration zones is 39–715 ppb. Gold is enriched in the minerals and rocks around faults and fissures, and is strongly concentrated in the advanced argillic alteration zone around faults. Hydrothermal solutions traveling along the fracture systems might be responsible for the comparatively high gold content in the study area. δ34S of alunites occurring in the advanced argillic alteration zone range from +16.5 to +3.9‰, although most are in a comparatively narrow range from +8.6 to +5.2‰. There is no difference between disseminated or massive and vein alunites. The δ34S of pyrites in the advanced argillic alteration zone are from +4.8 to −2.9‰. Oxygen and hydrogen isotope values of alunites are from +8.5 to 0‰ and from −59.6 to −97.3‰, respectively. With an assumed temperature of 200°C, δD and δ18O of hydrothermal solutions calculated for alunites are from −53.6 to −91.3‰, and from −2.4 to −8.1 for massive or disseminated alunites and from −6.6 to −10.9‰ for vein alunites, respectively. These data suggest that meteoric water dominated during the alunite formation. Isotopic data, geological setting, mineralogy, size of alunite and pure alunite composition (K end member) indicate that alunites of the study area were formed in the steam‐heated environment of acid sulfate alteration.
Exploring Causes of the Self‐serving Bias
Authors: Shepperd James , Malone Wendi , Sweeny Kate
Published: January 2008

The self‐serving bias refers to a tendency for people to take personal responsibility for their desirable outcomes yet externalize responsibility for their undesirable outcomes. We review a variety of explanations for this attribution bias. Although researchers have historically pitted cognitive and motivational explanations for the self‐serving bias against one another, cognitive and motivation processes often work in tandem to lead people to conclude that they are responsible for the desirable but not the undesirable outcomes.
Culture, Gender, and Men's Intimate Partner Violence
Authors: Vandello Joseph A. , Cohen Dov
Published: January 2008

This article reviews research on cultural beliefs and expectations about gender and romantic relationships that are related to male intimate partner violence. We link beliefs about men (manhood is tenuous and must be proven, men must protect women, and honor must be defended), about women (good women put sacrifice and family loyalty first and good women are morally and sexually pure), and about relationships (jealousy is a sign of passionate love) to show how they create a cultural context in which intimate partner violence is tolerated, accepted, or rejected. We end by discussing avenues for future research that take an expansive approach to examining culture's influence on intimate violence.
Outlines of a Critical Sociology of Consumption: Beyond Moralism and Celebration
Authors: Rief Silvia
Published: January 2008

The ‘new’ sociology of consumption that emerged in the 1980s acknowledged that consumption is a significant cultural and social practice and not just a mere signifier of the pathological elements of contemporary societies. Arguably, this rehabilitation of consumption has overshot its mark and has led to an overly positive, complacent and celebratory rendering of consumption and to an overriding concern with the symbolic and communicative dimension of goods. Driven by the debates on globalization, political consumerism and the relation between consumption and citizenship, current work shows increased interest in the politics of consumption. The article explores in what directions the classic concern with the symbolic and communicative dimension of goods might be taken if it is more thoroughly grounded in an analysis of the politics of consumption and of the current reconfigurations of consumers and citizens. The overall aim is to outline a basis for a critical sociology of consumption.
The Sociological Significance of Sleep: Progress, Problems and Prospects
Authors: Williams Simon J.
Published: January 2008

Sleep is something we all ‘do’ on a daily or nightly basis, consuming approximately a third of our lives. It is only relatively recently, however, that sociologists have begun to address the social significance of sleep. This paper, therefore, provides an invitation of sorts to a rich and fascinating new field of sociological inquiry, charting and commentating on the sociological significance of sleep in relation to the following seven key themes: (i) body and society; (ii) roles and routines; (iii) history and culture; (iv) work and employment; (v) gender and the life course; (vi) health and illness; and finally, (vii) politics and ethics. The paper concludes with some further critical thoughts and reflections on this sociological engagement with sleep to date and the theoretical, conceptual and methodological challenges ahead.
Composition‐Induced Variations in SIMS Instrumental Mass Fractionation during Boron Isotope Ratio Measurements of Silicate Glasses
Authors: Rosner Martin , Wiedenbeck Michael , Ludwig Thomas
Published: January 2008

An analytical artefact is reported here related to differences in instrumental mass fractionation between NIST SRM glasses and natural geological glasses during SIMS boron isotope determinations. The data presented demonstrated an average 3.4‰ difference between the NIST glasses and natural basaltic to rhyolitic glasses mainly in terms of their sputtering‐induced fractionation of boron isotopes. As no matrix effect was found among basaltic to rhyolitic glasses, instrumental mass fractionation of most natural glass samples can be corrected by using appropriate glass reference materials. In order to confirm the existence of the compositionally induced variations in boron SIMS instrumental mass bias, the observed offset in SIMS instrumental mass bias has been independently reproduced in two laboratories and the phenomenon has been found to be stable over a period of more than one year. This study highlights the need for a close match between the chemical composition of the reference material and the samples being investigated.
Models, Assumptions, and Stakeholders: Planning for Water Supply Variability in the Colorado River Basin1
Authors: Garrick Dustin , Jacobs Katharine , Garfin Gregg
Published: January 2008

Abstract:  Declining reservoir storage has raised the specter of the first water shortage on the Lower Colorado River since the completion of Glen Canyon and Hoover Dams. This focusing event spurred modeling efforts to frame alternatives for managing the reservoir system during prolonged droughts. This paper addresses the management challenges that arise when using modeling tools to manage water scarcity under variable hydroclimatology, shifting use patterns, and institutional complexity. Assumptions specified in modeling simulations are an integral feature of public processes. The policymaking and management implications of assumptions are examined by analyzing four interacting sources of physical and institutional uncertainty: inflow (runoff), depletion (water use), operating rules, and initial reservoir conditions. A review of planning documents and model reports generated during two recent processes to plan for surplus and shortage in the Colorado River demonstrates that modeling tools become useful to stakeholders by clarifying the impacts of modeling assumptions at several temporal and spatial scales. A high reservoir storage‐to‐runoff ratio elevates the importance of assumptions regarding initial reservoir conditions over the three‐year outlook used to assess the likelihood of reaching surplus and shortage triggers. An ensemble of initial condition predictions can provide more robust initial conditions estimates. This paper concludes that water managers require model outputs that encompass a full range of future potential outcomes, including best and worst cases. Further research into methods of representing and communicating about hydrologic and institutional uncertainty in model outputs will help water managers and other stakeholders to assess tradeoffs when planning for water supply variability.
Where within a geographical range do species survive best? A matter of scale
Authors: THOMAS CHRIS D. , BULMAN CAROLINE R. , WILSON ROBERT J.
Published: January 2008

Abstract. 

Opinions differ as to whether declining species are most likely to survive in central or peripheral parts of their distributions. The former pattern is likely to be driven by high extinction risks in peripheral areas; the latter by gradients of extinction risk.

At a continental scale of analysis, the declining butterflyEuphydryas auriniasurvived best in southern and eastern countries within Europe. This was statistically associated with geographical variation in agricultural intensification. At this scale of analysis, there was a gradient of survival, caused by a gradient of agricultural intensification.

Within England and Wales, survival was greatest in population concentrations, or core areas; that is in 10‐km grid squares that were surrounded by other 10‐km grid squares that also contained populations ofE. aurinia.In the English county of Dorset, populations were also most likely to be found in core areas; that is in habitat patches that were close to other populated habitat patches.

In this system, there is support for two patterns of decline. At a coarse scale, there is a geographical gradient of habitat degradation, associated with agricultural intensification. But within a region where decline has taken place, populations survive best in core areas, where aggregations of habitat support viable metapopulation dynamics.

Large‐scale geographical patterns of decline towards the periphery (or other locations within) the distribution of a species do not negate the validity of conservation strategies based on core‐margin population dynamic principles. Core areaswithineach country or region represent appropriate targets for conservation action.
Distribution of burnet moths (Zygaenaspp.) in relation to larval and adult resources on two spatial scales
Authors: ÖCKINGER ERIK
Published: January 2008

Abstract. 

Metapopulation theory predicts habitat patch area and isolation to be the main factors affecting the distribution of species dependent of patchily distributed habitats, but the need for multiple resources, which might be spatially separated, is often ignored.

Here, I studied the effect of host plant and nectar flower distributions on the spatial distribution of pupae and adults of two species of burnet moths (Zygaena filipendulaeandZygaena lonicerae), on two spatial scales.

At the landscape scale (10 × 12 km), moths were patchily distributed, but there was no effect of patch isolation on the occurrence of any of the species. On the local scale (2 × 2 km), I expected to find additive effects of the local abundances of larval and adult resources and their abundances in the surrounding areas, but instead, moth abundance decreased with increasing resource connectivity. I interpret this as an aggregation effect, such that at low resource abundances in the area, moths tend to aggregate in patches with higher flower densities.

My results also supported the hypothesis that the spatial distribution of individuals at one life stage is restricted by the requirement of other life stages, because the abundance of pupae of both species were associated with floral resources and abundance of imagos was related to larval resources.

I conclude that in studies aiming at understanding the relative importance of local and regional factors for species distributions, it is important to account for the habitat requirements of all life stages.
Choice of metrics for studying arthropod responses to habitat disturbance: one example from Gabon
Authors: BASSET YVES , MISSA OLIVIER , ALONSO ALFONSO , MILLER SCOTT E. , CURLETTI GIANFRANCO , MEYER MARC DE , EARDLEY CONNAL , LEWIS OWEN T. , MANSELL MERVYN W. , NOVOTNY VOJTECH , WAGNER THOMAS
Published: January 2008

Abstract. 

The choice of metrics comparing pristine and disturbed habitats may not be straightforward. We examined the results of a study in Gabon including 21 arthropod focal taxa representing 16 855 individuals separated into 1534 morphospecies. Replication included the understorey of 12 sites representing four stages of land use after logging (old and young forests, savanna and gardens), surveyed for 1 year using three sampling methods.

For all focal taxa, we calculated a suite of 13 metrics accounting for the intensity of faunal changes between habitats, namely: abundance; observed, rarefied and estimated species richness; proportion of rare species; additive diversity partitioning; evenness of assemblages; higher taxonomic composition; species turnover; ordination scores of multivariate analyses; nestedness; proportion of site‐specific species and ratios of functional guilds.

Most metrics showed large differences between forests and non‐forest habitats, but were not equally discriminating for particular taxa. Despite higher taxonomic groups being present in most habitats, many insect species were site or habitat specific. There was little evidence that the disturbance gradient represented a series of impoverished habitats derived from older forests. Rather, entire suites of species were being replaced as habitats were modified.

Metrics based on species identity had a high sensitivity to disturbance, whereas measurements describing community structure were less discriminating in this regard. We recommend using metrics based on abundance, estimated species richness, species turnover estimated by multivariate analyses and guild structure, to avoid misleading interpretations that may result from comparisons of species richness alone.
Prevalence of Early Childhood Caries in a Population of Children with History of Maltreatment
Authors: Valencia‐Rojas Nancy , Lawrence Herenia P. , Goodman Deborah
Published: January 2008

Objective: The purpose of this study was to investigate the prevalence of early childhood caries (ECC) in a population of maltreated children in Toronto, Ontario, Canada. Methods: The sample consisted of preschool‐aged children (2 to 6 years) admitted to the care of the Children's Aid Society of Toronto (CAST) between 1991 and 2004. Data were collected by reviewing the dental and social workers' records of CAST. ECC was determined using the decayed, missing, and filled deciduous teeth (dmft) index. The type and severity of maltreatment were obtained from the Eligibility Spectrum. Results: The study included 66 children: 37 (56 percent) boys and 29 (44 percent) girls, with an average age of 4.1 years [standard deviation (SD) = 1.2]. Four (6 percent) children had evidence of dental injury, and none had teeth filled or extracted as a result of decay. ECC was observed in 58 percent of the abused children. Of these, the mean decayed teeth (“dt”) value was 5.63 (SD = 4.17, n = 38) and 3.24 (SD = 4.21) for the whole sample (n = 66). The proportion of children with untreated caries was 57 percent among “neglected” children (n = 53) and 62 percent in physically/sexually abused cases (n = 13). Logistic regression revealed that children in permanent CAST care and those in its care more than once were significantly less likely to have experienced caries. Conclusions: Abused and neglected young children had higher levels of tooth decay than the general population of 5‐year‐olds in Toronto (30 percent prevalence, mean dt = 0.42, SD = 1.20, n = 3185). However, this study did not find any difference in ECC prevalence between children with different types of maltreatment. The study did find that CAST services had a protective effect on children's oral health, which supports the recommendation that child protection services should investigate possible dental neglect in physical/sexual abuse and neglect cases.
Racial/Ethnic Disparities in the Acceptance of Medicaid Patients in Dental Practices
Authors: Okunseri Christopher , Bajorunaite Ruta , Abena Albert , Self Karl , Iacopino Anthony M. , Flores Glenn
Published: January 2008

Objectives: Medicaid enrollees disproportionately experience dental disease and difficulties accessing needed dental care. However, little has been documented on the factors associated with the acceptance of new Medicaid patients by dentists, and particularly whether minority dentists are more likely to accept new Medicaid patients. We therefore examined the factors associated with the acceptance of new Medicaid patients by dentists. Methods: We analyzed 2001 data from the Wisconsin Dentist Workforce Survey administered by the Wisconsin Division of Health Care Financing, Bureau of Health Information. We used descriptive statistics and logistic regression analysis to examine the factors associated with the outcome variable. Results: Ninety‐four percent of Wisconsin licensed dentists (n = 4,301) responded to the 2001 survey. A significantly higher likelihood of accepting new Medicaid patients was found for racial/ethnic minority dentists (35 versus 19 percent of White dentists) and dentists practicing in large practices (31 versus 16 percent for those in smaller practices). In the multivariable analysis, minority dentists [odds ratio (OR) = 2.06, 95 percent confidence interval (CI) = 1.30, 3.25] and dentists in practices with >3 dentists (OR = 2.25, 95 percent CI = 1.69, 3.00) had significantly greater odds of accepting new Medicaid patients. Conclusions: Racial/ethnic minority dentists are twice as likely as White dentists to accept new Medicaid patients. Dentists in larger practices also are significantly more likely than those in smaller practices to accept new Medicaid patients. These findings suggest that increasing dental workforce diversity to match the diversity of the general US population can potentially improve access to dental care for poor and minority Americans, and may serve as an important force in reducing disparities in dental care.
Oral Health‐Related Quality of Life and Nutritional Status
Authors: Gil‐Montoya J. A. , Subirá C. , Ramón J. M. , González‐Moles M. A.
Published: January 2008

Objectives: This study examines whether oral health‐related quality of life (OHRQoL) is associated with malnutrition risk in the elderly. Methods: A cross‐sectional study was designed using a representative sample of Spaniards over 65 years old. Data on sociodemographics and oral health status were gathered by interview and examination. Oral health‐related quality of life was evaluated using the Geriatric Oral Health Assessment Index (GOHAI), and malnutrition risk using the Mini Nutritional Assessment (MNA). Results: The final sample included 2,860 elderly, 41.7 percent males and 58.3 percent females, with a mean age of 73.7 ± 6.8 years. Mean GOHAI score was 52.1 ± 7.2, with 70.7 percent of the sample needing oral health care according to this index. The mean MNA score was 24.0 ± 3.31; 3.5 percent of the elderly were malnourished, 31.5 percent were at risk of malnutrition, and 65.0 percent were considered adequately nourished. A strong association was found between mean GOHAI and MNA scores.
Sex‐ or gender‐specific medicine in hepatology
Authors: Nagoshi Sumiko
Published: January 2008

Sex‐ or gender‐specific medicine is an up‐to‐date medical science in recent medical care. Medical doctors must offer better medical care and should understand and elucidate the mechanisms underlying the sex or gender differences regarding the incidence or etiology, clinical features, and natural history or response to therapies. Sex or gender differences are frequently seen among liver diseases, such as viral hepatitis, alcoholic liver disease, non‐alcoholic fatty liver disease, autoimmune hepatitis, primary biliary cirrhosis, primary sclerosing cholangitis and hepatocellular carcinoma. The mechanisms of sex or gender differences, however, are still unclear. Clinicians and basic scientists are required to cooperatively contribute to the development of sex‐ or gender‐specific medicine to establish an accurate diagnosis and prophylaxis.
Are threat status and invasion success two sides of the same coin?
Authors: Jeschke Jonathan M. , Strayer David L.
Published: January 2008

Global change increases both the number of threatened species and the impacts of invasives. These two problems are sometimes assumed to be opposite sides of the same coin, with invasive species having the opposite characteristics of endangered species. However, the validity of this assumption has never been tested. We analysed 20 life‐history and other traits of all European and North American freshwater fish and birds. For these 1813 species, we compared the determinants of invasion success and IUCN‐threat status and found that traits favouring invasion are not simply the opposite of those that favour endangerment. The size and life history of species are correlated more strongly with threat status than invasiveness. On the other hand, association with humans is the best predictor of invasiveness but is not correlated with threat status. Thus, the rise of invaders is caused by different aspects of global change than the imperilment of endangered species.
Multifield coupled finite element analysis for sound transmission in otitis media with effusion
Authors: Gan Rong Z. , Wang Xuelin
Published: February 2008

In this paper, a newly constructed three-dimensional finite element (FE) model of the human ear based on histological sections of a left ear temporal bone is reported. The otitis media with effu-sion was simulated in the model with variable fluid levels in the middle ear. The interfaces among the air, structure, and fluid in the ear canal and middle ear cavity were identified and the acoustic-structure-fluid coupled FE analysis was conducted when the middle ear fluid level was varied from zero to full fill of the cavity. The results show how the displacements of the tympanic membrane and stapes footplate or the middle ear transfer function is affected by fluid in the cavity across the auditory frequencies. Comparison of model results with measured data in temporal bones indicates that this model has the capability to extend FE analysis into pathological ears such as otitis media with visualized fluid-air interfaces inside the middle ear structures.
A computer model of medial efferent suppression in the mammalian auditory system
Authors: Ferry Robert T. , Meddis Ray
Published: February 2008

Stimulation of the olivocochlear bundle reduces basilar membrane displacement, driven auditory nerve activity, and compound action potential (CAP) response to acoustic stimulation. These effects were simulated using a computer model of the auditory periphery. The model simulates the medial efferent activity by attenuating the basilar membrane response. The model was evaluated against three animal studies reporting measurements at three levels of the auditory system; basilar membrane, single auditory nerve fibers and whole auditory nerve CAP. The CAP data included conditions where tones were masked by noise and “unmasked” by stimulation of the olivocochlear bundle. The model was able to simulate the data both qualitatively and quantitatively. As a consequence, it may be a suitable platform for studying the contribution of the efferent system to auditory processing of more complex auditory sounds in distracting backgrounds.
Serum Bactericidal Antibody Responses to Meningococcal Polysaccharide Vaccination as a Basis for Clinical Classification of Common Variable Immunodeficiency
Authors: Rezaei Nima , Aghamohammadi Asghar , Siadat Seyed Davar , Moin Mostafa , Pourpak Zahra , Nejati Mehdi , Ahmadi Hojat , Kamali Samineh , Norouzian Dariush , Tabaraei Bahman , Read Robert C.
Published: January 2008

Common variable immunodeficiency (CVID) is a heterogeneous group of disorders characterized by hypogammaglobulinemia and increased susceptibility to recurrent pyogenic infections. This study was performed to subclassify CVID on the basis of the bactericidal antibody responses of patients to polysaccharide meningococcal vaccine. Twenty-five patients with CVID (18 male and 7 female) and 25 healthy volunteers received meningococcal polysaccharide vaccine A + C. Serum bactericidal antibody (SBA) titers were measured at baseline and after 3 weeks. Response was correlated with clinical and immunological manifestations of CVID. Twenty-four (96%) of the 25 normal controls had a protective SBA titer of ≥8 postvaccination, whereas only 16 (64%) of the 25 CVID patients had a protective titer (
P
value = 0.013). Among the patients with CVID who were nonresponders, there were significantly increased rates of bronchiectasis (
P
= 0.008), splenomegaly (
P
= 0.016), and autoimmunity (
P
= 0.034) in comparison with patients who had protective SBA titers. A reversed CD4/CD8 ratio was more common in the nonresponder group of patients (
P
= 0.053). We conclude that individuals with CVID who cannot produce protective postvaccination titers after receiving meningococcal polysaccharide vaccine are more likely to exhibit bronchiectasis, splenomegaly, and autoimmune diseases. Vaccination response may define subgroups of patients with CVID, enabling more effective monitoring and therapeutic strategies.
Multiple Combinations of P[13]-Like Genotype with G3, G4, and G5 in Porcine Rotaviruses
Authors: Chan-it Wisoot , Khamrin Pattara , Saekhow Prayuth , Pantip Chansom , Thongprachum Aksara , Peerakome Supatra , Ushijima Hiroshi , Maneekarn Niwat
Published: January 2008

Epidemiological surveillance of porcine rotavirus (PoRV) strains was carried out in Chiang Mai Province, Thailand, from 2002 to 2003, and eight rotavirus isolates could not be completely typed by PCR. Of these, six were G3 and one was G4 and displayed a P-nontypeable genotype, while another isolate was both G and P nontypeable. Analysis of a partial VP4 gene of all eight P-nontypeable strains revealed a high degree of amino acid sequence identities (94.7% to 100%), suggesting that they belonged to the same P genotype. Comparison of the amino acid sequences of two representative strains (namely, strains CMP178 and CMP213) with those of 27 other known P genotypes revealed a high degree of amino acid sequence identity with those of P[13] porcine rotavirus reference strains HP113 and HP140, which were recently isolated in India. However, amino acid sequence comparison with non-P[13] rotavirus strains revealed relatively low identities, ranging from 58.2% to 84.8% for full-length VP4 sequences and 35.1% to 80.6% for VP8* sequences. Phylogenetic analysis revealed that CMP178 and CMP213 clustered together in a monophyletic branch with P[13]-like genotypes HP113 and HP140 which was clearly separated from the other lineages of P[13] or P[22] strains. Altogether, these findings indicate that PoRV strains CMP178 and CMP213 should be considered the P[13]-like VP4 genotype, a rare genotype that has been identified only in pigs. This study provides additional evidence of increasing genetic diversity among group A rotaviruses in nature.
Reductions in Workload and Reporting Time by Use of Methicillin-Resistant
Staphylococcus aureus
Screening with MRSA
Select
Medium Compared to Mannitol-Salt Medium Supplemented with Oxacillin
Authors: Lagacé-Wiens Philippe R. S. , Alfa Michelle J. , Manickam Kanchana , Harding Godfrey K. M.
Published: January 2008

Methicillin-resistant
Staphylococcus aureus
(MRSA) is a significant pathogen in both nosocomial and community settings, and screening for carriers is an important infection control practice in many hospitals. In this retrospective study, we demonstrate that the implementation of an MRSA screening protocol using a selective chromogenic medium (MRSA
Select
) reduced the workload for this screening test by 63.7% overall and by 12.6% per specimen and reduced the turnaround time for reporting by an average of 1.33 days for all MRSA screening specimens, 1.97 days for MRSA-positive specimens, and 1.3 days for MRSA-negative specimens compared to standard mannitol-salt agar supplemented with 6 mg of oxacillin/liter.
Identification of
Staphylococcus aureus
and Determination of Methicillin Resistance Directly from Positive Blood Cultures by Isothermal Amplification and a Disposable Detection Device
Authors: Goldmeyer James , Li Haijing , McCormac Melinda , Cook Steve , Stratton Charles , Lemieux Bertrand , Kong Huimin , Tang Wen , Tang Yi-Wei
Published: January 2008

A simple, rapid, and user-friendly procedure has been developed to identify
Staphylococcus aureus
and determine its methicillin resistance directly from gram-positive cocci in cluster-containing blood culture medium. The specimens were diluted and heated prior to amplification of the
nuc
and
mecA
genes with isothermal helicase-dependent amplification. Amplicons were detected using a disposable detection device. The analytical sensitivity of the assays was 50 CFU per reaction, and the clinical sensitivity and specificity were both 100% for
S. aureus
detection and 100% and 98% for methicillin resistance determination, respectively.
Molecular Epidemiology of Rotavirus Diarrhea among Children in Saudi Arabia: First Detection of G9 and G12 Strains
Authors: Kheyami Ali M. , Nakagomi Toyoko , Nakagomi Osamu , Dove Winifred , Hart C. Anthony , Cunliffe Nigel A.
Published: January 2008

In anticipation of rotavirus vaccine introduction in Saudi Arabia, this study was undertaken to determine the distribution of the G and P genotypes of rotaviruses in order to examine whether there was any emerging serotype or unusual strain circulating in children in Saudi Arabia. Of 984 stool specimens collected between 17 April 2004 and 16 April 2005, rotavirus was detected by an enzyme-linked immunosorbent assay in 187 (19%) diarrheal children less than 5 years of age. Of these, 160 (86%) were classified into G and P genotypes as follows: G1P[8] (44%), G2P[4] (20%), G9P[8] (11%), G12P[8] (4%), and G3P[8] (4%). RNA polyacrylamide gel electrophoresis identified 94 (50%) specimens as long RNA patterns, 30 (16%) specimens as short RNA patterns, and 1 mixed infection. Only a single long RNA electropherotype was identified for seven specimens containing G12P[8] rotavirus. RNA-RNA hybridization demonstrated that the G12P[8] strains were similar in their genomic constellation to locally cocirculating strains and to a Nepalese G12P[8] strain. The Saudi Arabian G12 VP7 gene had a 99% nucleotide sequence identity with Nepalese and Indian G12 VP7 genes and belonged to the third lineage. This study is the first to describe the distribution of rotavirus G and P types and also the first to identify G9P[8] and G12P[8] strains in the country.
Prevalence of Human Metapneumovirus in Central Illinois in Patients Thought To Have Respiratory Viral Infection
Authors: Barenfanger Joan , Mueller Tina , O'Brien Janet , Drake Cheryl , Lawhorn Jerry
Published: January 2008

Studies suggest that by age 5 years nearly all people have been exposed to metapneumovirus. To determine its prevalence in central Illinois, we tested respiratory secretions by direct immunofluorescence staining from December to March. Metapneumovirus was detected in 11/391 specimens. The distribution of metapneumovirus was bimodal, with the split being between children aged ≤4 years and adults.
Efficient In Vitro Expansion of Human Immunodeficiency Virus (HIV)-Specific T-Cell Responses bygagmRNA-Electroporated Dendritic Cells from Treated and Untreated HIV Type 1-Infected Individuals
Authors: Van Gulck Ellen R. , Vanham Guido , Heyndrickx Leo , Coppens Sandra , Vereecken Katleen , Atkinson Derek , Florence Eric , Kint Ilse , Berneman Zwi Nisan , Tendeloo Viggo Van
Published: January 2008

Developing an immunotherapy to keep human immunodeficiency virus type 1 (HIV-1) replication suppressed while discontinuing highly active antiretroviral therapy (HAART) is an important challenge. In the present work, we evaluated in vitro whether dendritic cells (DC) electroporated withgagmRNA can induce HIV-specific responses in T cells from chronically infected subjects. Monocyte-derived DC, from therapy-naïve and HAART-treated HIV-1-seropositive subjects, that were electroporated with consensus codon-optimized HxB2gagmRNA efficiently expanded T cells, secreting gamma interferon (IFN-γ) and interleukin 2 (IL-2), as well as other cytokines and perforin, upon restimulation with a pool of overlapping Gag peptides. The functional expansion levels after 1 week of stimulation were comparable in T cells from HAART-treated and treatment-naïve patients and involved both CD4+and CD8+T cells, with evidence of bifunctionality in T cells. Epitope mapping of p24 showed that stimulated T cells had a broadened response toward previously nondescribed epitopes. DC, from HAART-treated subjects, that were electroporated with autologous proviralgagmRNA equally efficiently expanded HIV-specific T cells. Regulatory T cells did not prevent the induction of effector T cells in this system, whereas the blocking of PD-L1 slightly increased the induction of T-cell responses. This paper shows that DC, loaded with consensus or autologousgagmRNA, expand HIV-specific T-cell responses in vitro.
Cellular Proteasome Activity Facilitates Herpes Simplex Virus Entry at a Postpenetration Step
Authors: Delboy Mark G. , Roller Devin G. , Nicola Anthony V.
Published: January 2008

Herpes simplex virus (HSV) entry into cells is a multistep process that engages the host cell machinery. The proteasome is a large, ATP-dependent, multisubunit protease that plays a critical role in the maintenance of cell homeostasis. A battery of assays were used to demonstrate that proteasome inhibitors blocked an early step in HSV entry that occurred after capsid penetration into the cytosol but prior to capsid arrival at the nuclear periphery. Proteasome-dependent viral entry was not reliant on host or viral protein synthesis. MG132, a peptide aldehyde that competitively inhibits the degradative activity of the proteasome, had a reversible inhibitory effect on HSV entry. HSV can use endocytic or nonendocytic pathways to enter cells. These distinct entry routes were both dependent on proteasome-mediated proteolysis. In addition, HSV successfully entered cells in the absence of a functional host ubiquitin-activating enzyme, suggesting that viral entry is ubiquitin independent. We propose that proteasomal degradation of virion and/or host proteins is required for efficient delivery of incoming HSV capsids to the nucleus.
Epstein-Barr Virus Lytic Transactivator Zta Enhances Chemotactic Activity through Induction of Interleukin-8 in Nasopharyngeal Carcinoma Cells
Authors: Hsu Meichi , Wu Shih-Yi , Chang Shih-Shin , Su Ih-Jen , Tsai Ching-Hwa , Lai Siao-Jing , Shiau Ai-Li , Takada Kenzo , Chang Yao
Published: January 2008

Epstein-Barr virus (EBV)-associated, undifferentiated type of nasopharyngeal carcinoma (NPC) is characterized by intensive leukocyte infiltration. Interaction between the infiltrating cells and the tumor cells has been considered crucial for NPC development. Recruitment of the infiltrates can be directed by certain chemokines present in the NPC tissues. It is unknown whether and how EBV lytic infection regulates expression of the chemokines. Using an antibody array, we first found that several chemokines secreted from EBV-infected NPC cells are increased upon EBV reactivation into the lytic cycle, and interleukin-8 (IL-8) is the chemokine upregulated most significantly and consistently. Further studies showed that the EBV lytic transactivator Zta is a potent inducer of IL-8 in NPC cells, augmenting secreted and intracellular IL-8 proteins, as well as IL-8 RNA. Zta upregulates Egr-1, a cellular transcription factor that has been involved in upregulation of IL-8, but the Zta-induced IL-8 expression is independent of Egr-1. The ability of Zta to transactivate the IL-8 promoter is important for the induction of IL-8, and we have identified two Zta-responsive elements in the promoter. Zta can bind to these two elements in vitro and can also be recruited to the IL-8 promoter in vivo. DNA-binding-defective Zta mutants can neither activate the IL-8 promoter nor induce IL-8 production. In addition, Zta-expressing NPC cells exert enhanced chemotactic activity that is mainly mediated by IL-8. Since IL-8 may contribute to not only leukocyte infiltration but also multiple oncogenic processes, the present study provides a potential link between EBV lytic infection and pathogenesis of NPC.
Differential Inhibition of Nuclear Hormone Receptor-Dependent Hepatitis B Virus Replication by the Small Heterodimer Partner
Authors: Oropeza Claudia E. , Li Lie , McLachlan Alan
Published: January 2008

The nuclear hormone receptors hepatocyte nuclear factor 4 (HNF4) and retinoid X receptor α (RXRα) plus peroxisome proliferator-activated receptor α (PPARα) heterodimer support hepatitis B virus (HBV) pregenomic RNA synthesis and viral replication in nonhepatoma cells. Small heterodimer partner (SHP), an orphan nuclear hormone receptor lacking a DNA binding domain, inhibits nuclear hormone receptor-mediated viral transcription and replication. The inhibition of HBV replication by SHP is dependent on the presence of nuclear hormone receptors. HBV replication that is dependent on HNF4 is considerably more sensitive to SHP-mediated inhibition than RXRα/PPARα-directed viral biosynthesis. SHP inhibition of HBV biosynthesis in HepG2 cells suggests that multiple nuclear hormone receptors mediate viral replication in this human hepatoma cell line. These observations suggest that the physiological regulation of HBV biosynthesis by SHP in the liver will depend on both the level of SHP expression and the relative contribution of HNF4 and RXRα/PPARα, plus potentially additional nuclear hormone receptors, to HBV RNA synthesis and replication.
Synthesis of Novel Carbocyclic Nucleoside Analogues Containing Bicyclo[2.2.1]hept-2-ene-2-methanol
Authors: Hřebabecký Hubert , Dračínský Martin , Holý Antonín
Published: January 2008

Starting ethyl (1R*,2R*,3R*,4S*)-3-bromobicyclo[2.2.1]hept-5-ene-2-carboxylate (9) was reduced with LiAlH4and benzoylated giving [(1R*,2R*,3R*,4S*)-3-bromobicyclo[2.2.1]hept-5-en-2-yl]methyl benzoate (11). Treatment of11with NaN3and CrO3in acetic acid afforded [(1R*,2S*,3R*,4R*,5S*,6R*)-6-azido-3-bromo-5-hydroxybicyclo[2.2.1]hept-2-yl]methyl benzoate (12a) and [(1R*,2S*,3S*,4R*,5S*,6R*)-5-azido-3-bromo-6-hydroxybicyclo[2.2.1]heptan-2-yl]-methyl benzoate (12b). These key intermediates were separated and converted in five reaction steps to (1R*,2R*,3S*,4S*)-3-[(5-amino-6-chloropyrimidin-4-yl)amino]-5-(hydroxymethyl)- bicyclo[2.2.1]hept-5-en-2-ol (17a) and (1R*,2R*,3S*,4S*)-3-[(5-amino-6-chloropyrimidin-4-yl)- amino]-6-(hydroxymethyl)bicyclo[2.2.1]hept-5-en-2-ol (17b). Ring closure with triethyl orthoformate led to (1R*,2R*,3S*,4S*)-5-(chloromethyl)-3-(6-chloro-9H-purin-9-yl)bicyclo[2.2.1]hept-5-en-2-ol (18a) and (1R*,2R*,3S*,4S*)-6-(chloromethyl)-3-(6-chloro-9H-purin-9-yl)- bicyclo[2.2.1]hept-5-en-2-ol (18b) using hydrochloric acid as a catalyst or (1R*,2R*,3S*,4S*)-3-(6-chloro-9H-purin-9-yl)-5-(hydroxymethyl)bicyclo[2.2.1]hept-5-en-2-ol (19a) and (1R*,2R*,3S*,4S*)- 3-(6-chloro-9H-purin-9-yl)-6-(hydroxymethyl)bicyclo[2.2.1]hept-5-en-2-ol (19b) using trifluoro- acetic acid as a catalyst. From19aand19b, 6-amino- and 6-(cyclopropylamino)purine derivatives20and21were prepared.
EFFECT OF BENZIMIDAZOLE, DIMETHYLBENZIMIDAZOLE, GLUCOSE, AND METAL IONS ON THE DEVELOPMENT OF PUCCINIA GRAMINIS TRITICI ON DETACHED LEAVES OF KHAPLI WHEAT
Authors: Wang Dalton
Published: January 2008

Leaves of Khapli wheat which are normally resistant to race 15B-1 of Puccinia graminis tritici become susceptible when detached and floated on water. This breakdown of resistance can be reversed by floating the detached leaves on a solution of benzimidazole. The effect of benzimidazole, however, can be nullified by a supply of exogenous glucose or 5,6-dimethylbenzimidazole. Furthermore, the resistance can again be restored by the presence of cobalt ion combined in solution with glucose and benzimidazole or with glucose and 5,6-dimethylbenzimidazole. Cobalt ions alone, or in combination with glucose, or with benzimidazole, or with 5,6-dimethylbenzimidazole separately have no effect on rust development. In contrast, nickel ion alone or in any combination has a profound inhibitory effect on the development of rust in detached leaves. Other chemicals were also included in this study, and their effect on rust development is discussed. It is speculated that benzimidazole or a derivative of it and cobalt may form a vitamin B12-like factor which is required by the host to maintain its normal metabolic activities.