bluuebunny/crossref_metadata_2025_split huggingface dataset:
Following the gas flows from nuclear spirals to the accretion disk
Authors: Storchi-Bergmann Thaisa 
Published: May 2007

AbstractA recent analysis of HST optical images of 34 nearby early-type active galaxies and of a matched sample of 34 inactive galaxies – both drawn from the Palomar survey – shows a clear excess of nuclear dusty structures (filaments, spirals and disks) in the active galaxies. This result supports the association of the dusty structures with the material which feeds the supermassive black hole (hereafter SMBH). Among the inactive galaxies there is instead an excess of nuclear stellar disks. As the active and inactive galaxies can be considered two phases of the “same” galaxy, the above findings and dust morphologies suggest an evolutionary scenario in which external material (gas and dust) is captured to the nuclear region where it settles and ends up feeding the active nucleus and replenishing the stellar disk – which is hidden by the dust in the active galaxies – with new stars. This evolutionary scenario is supported by recent gas kinematics of the inner few hundred parsecs of NGC 1097, which shows streaming motions (with velocities ∼50 km s−1) towards the nucleus along spiral arms. The implied large scale mass accretion rate is much larger than the one derived in previous studies for the nuclear accretion disk, but is just enough to accumulate one million solar masses over a few million years in the nuclear region, thus consistent with the recent finding of a young circumnuclear starburst of one million solar masses within 9 parsecs from the nucleus in this galaxy.
The thermal—viscous disk instability model in the AGN context
Authors: Hameury Jean-Marie , Lasota Jean-Pierre , Viallet Maxime 
Published: May 2007

AbstractAccretion disks in AGN should be subject to the same disk instability responsible for dwarf novae outbursts and soft X-ray transients in cataclysmic variables (CVs) and LMXBs. It has been suggested that this thermal/viscous instability can account for long term variability of AGNs. We analyze here the application of the DIM to the AGN case, using our adaptive grid numerical code developed in the context of CVs, enabling us to fully resolve the disk radial structure. We show that in AGNs, the width of heating and cooling fronts is so small that they cannot be resolved by standard codes, and that they propagate on time scales much shorter than the viscous time. As a result, transition fronts propagate back and forth in the disk, leading only to small luminosity variations. Truncation of the inner part of the disk by e.g. an ADAF will not alter this result, but enables the presence of quiescent states.
Variations of geometrical and physical characteristics of innermost regions of active galactic nuclei on time-scale of years
Authors: Bochkarev Nikolai G. , Shapovalova Alla I. 
Published: May 2007

AbstractSeveral examples of observational evidence of possible variations of geometrical and physical characteristics of the Broad Line Regions (BLR) of AGN on the time-scale of years are listed. Cases of accretion disk size variations and variable input of jets in BLR formation are presented.
Radiation in models with cosmological constant
Authors: Kadlecová Hedvika , Podolský Jiří 
Published: May 2007

AbstractWe analyze the asymptotic directional structure and properties of gravitational field of specific exact solutions belonging to the large family of black hole spacetimes of type D found by Plebański and Demiański. We discuss the structure in the case of de Sitter (Λ>0) and anti–de Sitter (Λ<0) conformal infinity. With the aim of further interpretation, we have found the relation between the structure of the sources (the mass m, the electric e and magnetic g charges, the NUT parameter l, the rotational parameter a, the acceleration α) and the properties of radiation generated by them. In particular, we studied the amplitude of radiation and illustrated it in several figures.
The results of X-ray binary Cyg X-1 investigations based on the optical photometry and high-resolution spectroscopy
Authors: Karitskaya Eugenia A. 
Published: May 2007

AbstractSelected results of 1994-2004 optical photometric and high-resolution spectral observations including those obtained in the frame of a coordinated CIS countries campaign “Optical Monitoring of Unique Astrophysical Objects” and their comparison with ASM/RXTE X-ray data are briefly reviewed.
Long-term photometry of blazars at Abastumani Observatory
Authors: Kurtanidze Omar M. , Nikolashvili Maria G. , Kimeridze Givi N. , Sigua Lorand A. , Kapanadze Bidzina Z. , Ivanidze Roman Z. 
Published: May 2007

AbstractWe give a brief summary of the ongoing Abastumani Active Galactic Nuclei Monitoring Program started in the May 1997. More than 110000 frames are obtained during more than 1300 nights of observations for about 50 target objects, among them gamma-ray, X-ray and optical blazars. All observations were done in the BVRI bands using ST-6 CCD based photometer attached to the Newtonian focus of 70-cm meniscus telescope.
XMM-Newton study of the spectral variability in NLS1 galaxies
Authors: Ponti G. , Cappi M. , Czerny B. , Goosmann R. W. , Karas V. 
Published: May 2007

AbstractPreliminary results of the study of the X-ray spectral variability of 12 Narrow Line Seyfert 1 (NLS1) galaxies are presented. Rms spectra are calculated and compared for the whole sample to search for possible variations with black hole mass. A larger sample of AGN is under investigation.
Observational properties of relativistic black hole winds
Authors: Watarai Ken-ya 
Published: May 2007

AbstractWe examine observational properties of relativistic black hole winds as an origin of high luminosity sources such as microquasars and ultra-luminous X-ray sources (ULXs). When strong relativistic wind/outflow happens in the vicinity of the black hole, the wind might form the optically-thick photosphere. Therefore the emission observed in ULXs might come from the photosphere of the wind, not from the accretion disk.We found that the location of the photosphere is larger than the disk thickness for super-Eddington mass-outflow rates and sub-relativistic wind velocities (v ∼ 0.1–0.2 c). To understand the radiative structure in the high luminosity sources, we should take into account not only the emission from the accretion disk but also the emission from the outflow at the same time.
First 3‐D images of the Sun
Authors: Kumar Mohi 
Published: May 2007

NASA's twin Solar Terrestrial Relations Observatory (STEREO) spacecraft have produced the first three‐dimensional images of the Sun. The images, released on 23 April, will allow scientists to better understand and model solar storms and the drivers of adverse space weather.Launched on 25 October 2006, the STEREO spacecraft circle the Sun close to Earth's orbit, and are separating from each other on their orbital arc by about 45 degrees per year. Currently, the offset between the spacecraft has grown to the point where simultaneous views of the Sun from each spacecraft provide depth perception when combined, similar to the eyes on a person's face.
Issues in planetary chronology
Authors: Barlow Nadine G. , Schenk Paul , Bierhaus E. Beau 
Published: May 2007

The ‘Workshop on Surface Ages and Histories: Issues in Planetary Chronology’ brought together researchers from the impact cratering, radiometric analysis, and numerical modeling communities to discuss the current status of chronologic techniques and identify future research directions.Heavily cratered terrains suggest that the inner solar system impact rate was much higher 3.8–4.4 Ga ago (1 Ga = 109 years). Impact rates declined after this late heavy bombardment (LHB) period to a level that has been approximately constant for the past 3.8 Ga. A major question is whether the LHB was a gradual decline or a spike near 4.0 Ga. Dynamical modeling of outer planet migrations reveals a mechanism for perturbing material into the inner solar system between 3.8 and 4.0 Ga. Geochronologic evidences from the Moon, Earth, and asteroids also support a cataclysmic LHB.
Landslides: Processes, Prediction, and Land Use [An interview with the author]
Authors: Kumar Mohi 
Published: May 2007

As population grows and land use needs change, humans become more vulnerable to landslide hazards. An AGU book, Landslides: Processes, Prediction, and Land Use, written by Roy C. Sidle and Hirotaka Ochiai, suggests that different human activities exacerbate landslide risk, and details current methods in landslide prediction and modeling techniques.In this issue, Eos talks with Sidle. Sidle has studied landslides for nearly 30 years and is currently head of the Slope Conservation Section at Kyoto University's Disaster Prevention Research Institute (Japan).
Functional microarray analysis of nitrogen and carbon cycling genes across an Antarctic latitudinal transect
Authors: Yergeau Etienne , Kang Sanghoon , He Zhili , Zhou Jizhong , Kowalchuk George A 
Published: May 2007

AbstractSoil-borne microbial communities were examined via a functional gene microarray approach across a southern polar latitudinal gradient to gain insight into the environmental factors steering soil N- and C-cycling in terrestrial Antarctic ecosystems. The abundance and diversity of functional gene families were studied for soil-borne microbial communities inhabiting a range of environments from 51°S (cool temperate – Falkland Islands) to 72°S (cold rock desert – Coal Nunatak). The recently designed functional gene array used contains 24 243 oligonucleotide probes and covers &gt;10 000 genes in &gt;150 functional groups involved in nitrogen, carbon, sulfur and phosphorus cycling, metal reduction and resistance and organic contaminant degradation (He et al. 2007). The detected N- and C-cycle genes were significantly different across different sampling locations and vegetation types. A number of significant trends were observed regarding the distribution of key gene families across the environments examined. For example, the relative detection of cellulose degradation genes was correlated with temperature, and microbial C-fixation genes were more present in plots principally lacking vegetation. With respect to the N-cycle, denitrification genes were linked to higher soil temperatures, and N2-fixation genes were linked to plots mainly vegetated by lichens. These microarray-based results were confirmed for a number of gene families using specific real-time PCR, enzymatic assays and process rate measurements. The results presented demonstrate the utility of an integrated functional gene microarray approach in detecting shifts in functional community properties in environmental samples and provide insight into the forces driving important processes of terrestrial Antarctic nutrient cycling.
Effect of Education on the Rate of and the Understanding of Risk Factors for Intravascular Catheter–Related Infections
Authors: Yilmaz G. , Caylan R. , Aydin K. , Topbas M. , Koksal I. 
Published: May 2007

Objective.Intravascular catheters are indispensable tools in modern medical therapy. In spite of their great benefits, however, the widespread use of catheters leads to several complications, including infections that cause significant morbidity, mortality, and economic losses for hospitalized patients.Design.This study was conducted at Farabi Hospital, a 495-bed facility at Karadeniz Technical University Medical School in Trabzon, Turkey, and involved 3 separate periods: preeducation, education, and posteducation. Patients with intravascular catheters were monitored daily, as were the results of their physical examinations. The information acquired was recorded in a questionnaire.Results.During the preeducation period (October 2003 through March 2004), 405 intravascular catheters inserted into 241 patients were observed for 5,445 catheter-days. Seventy-one cases of intravascular catheter-related infection (CRI) were identified, giving a CRI rate of 13.04 infections per 1,000 catheter-days. The catheter-related bloodstream infection (CRBSI) rate was 8.3 infections per 1,000 catheter-days, and the exit-site infection (ESI) rate was 3.5 infections per 1,000 catheter-days. During the posteducation period (June through November 2004), 365 intravascular catheters inserted into 193 patients were observed for 5,940 catheter-days. Forty-five cases of CRI were identified, giving a rate of 7.6 infections per 1,000 catheter-days. The CRBSI rate was 4.7 infections per 1,000 catheter-days, and the ESI rate was 2.2 infections per 1,000 catheter-days. When findings from the 2 periods were compared, it was determined that education reduced CRI incidence by 41.7%.Conclusion.CRI can be prevented when hospital personnel are well informed about these infections. We compared the knowledge levels of the relevant personnel in our hospital before and after theoretical and practical training and identified a significant increase in knowledge after training (P< .0001 ). Parallel to this, although still below ideal levels, we identified a significant improvement in the incidence of CRI during the posteducation period (P = .004). The rate was low for the first 3 months of this period but increased 2.08 times after the third month. In conclusion, regular training for the residents in charge of inserting intravascular catheters and the nurses and interns who maintain the catheters is highly effective in reducing the rate of CRI in large teaching hospitals.
Value of Performing Active Surveillance Cultures on Intensive Care Unit Discharge for Detection of Methicillin-ResistantStaphylococcus aureus
Authors: Furuno Jon P. , Harris Anthony D. , Wright Marc-Oliver , Hartley David M. , McGregor Jessina C. , Gaff Holly D. , Hebden Joan N. , Standiford Harold C. , Perencevich Eli N. 
Published: May 2007

Objective.To quantify the value of performing active surveillance cultures for detection of methicillin-resistantStaphylococcus aureus(MRSA) on intensive care unit (ICU) discharge.Design.Prospective cohort study.Setting.Medical ICU (MICU) and surgical ICU (SICU) of a tertiary care hospital.Participants.We analyzed data on adult patients who were admitted to the MICU or SICU between January 17, 2001, and December 31, 2004. All participants had a length of ICU stay of at least 48 hours and had surveillance cultures of anterior nares specimens performed on ICU admission and discharge. Patients who had MRSA-positive clinical cultures in the ICU were excluded.Results.Of 2,918 eligible patients, 178 (6%) were colonized with MRSA on ICU admission, and 65 (2%) acquired MRSA in the ICU and were identified by results of discharge surveillance cultures. Patients with MRSA colonization confirmed by results of discharge cultures spent 853 days in non-ICU wards after ICU discharge, which represented 27% of the total number of MRSA colonization-days during hospitalization in non-ICU wards for patients discharged from the ICU.Conclusions.Surveillance cultures of nares specimens collected at ICU discharge identified a large percentage of MRSA-colonized patients who would not have been identified on the basis of results of clinical cultures or admission surveillance cultures alone. Furthermore, these patients were responsible for a large percentage of the total number of MRSA colonization-days during hospitalization in non-ICU wards for patients discharged from the ICU.
Assessment of Adverse Events Associated With Antiretroviral Regimens for Postexposure Prophylaxis for Occupational and Nonoccupational Exposures to Prevent Transmission of Human Immunodeficiency Virus
Authors: Luque A. , Hulse S. , Wang D. , Shahzad U. , Tanzman E. , Antenozzi S. , Smith B. 
Published: May 2007

Objective.To assess adverse events associated with antiretroviral regimens for human immunodeficiency virus (HIV) postexposure prophylaxis (PEP), with a particular focus on the treatment combination of zidovudine, lamivudine, and tenofovir (ZDV-3TC-TDF).Methods.Retrospective chart review for individuals who received HIV PEP for occupational and nonoccupational exposure, and multivariate analyses to identify risk factors for noncompletion of PEP and adverse events associated with PEP.Setting.University of Rochester Health Service Occupational Health Program and University of Rochester AIDS Center.Participants.Healthcare workers who received HIV PEP for occupational exposure from January 1, 1999, to December 31, 2004, and individuals who received HIV PEP for nonoccupational exposure from January 1, 2002, to December 31, 2004.Results.We found increased rates of nausea among subjects who received treatment with ZDV-3TC-TDF and subjects who received treatment with zidovudine, lamivudine, and indinavir (ZDV-3TC-IDV). Analyses showed that female sex was a risk factor for nausea. Compared with subjects who received treatment with ZDV-3TC-TDF, subjects who received treatment with ZDV-3TC-IDV were less likely to not complete the HIV PEP for occupational exposure.Conclusion.Preventive treatment of adverse events may be necessary to ensure completion of HIV PEP.
Eradication of Amebiasis in a Large Institution for Adults With Mental Retardation in Taiwan
Authors: Su Shih-Bin , Guo How-Ran , Chuang Yin-Ching , Chen Kow-Ton , Lin Ching-Yih 
Published: May 2007

Objective.Investigation of a program to eradicate amebiasis using consecutive intensive mass screenings followed by medication in a large institute for adults with mental retardation in Taiwan.Design.Prospective cohort study, with 3 years of follow-up.Setting.A large, 450-bed institution for adults with mental retardation located in southern Taiwan.Participants.All 443 adults with mental retardation in the institution, who have various motor and/or mental handicaps, were included in this study.Interventions. A total of 7 consecutive intensive mass screenings for amebiasis for all residents (performed in March, August and November 2001, March and August 2002, January 2003, and May 2004). Infected patients were treated using the standard protocol of the Center for Disease Control of Taiwan.Results.Enzyme immunoassay testing was used for the amebiasis screening, with the rapid detection of the specific antigen for Entamoeba histolytica in human fecal specimens confirmed by microscopic examination. The serial prevalence and cumulative incidence were then calculated. The prevalence of amebic infection declined in serial screenings, but new infections and reinfections were detected in 5 of 6 follow-up screenings. The prevalence was 10.8% at the beginning of the program and then gradually reduced, falling to 6.3%, 3.6%, 2.7%, 3.4%, and 2.2%. Finally, no more positive cases were identified in the last screening (May 2004). The cumulative incidence rate stabilized at around 40% by the fifth screening. Of the 179 infected patients, 120 had primary infections, with 59 cases of multiple amebic infections.Conclusions.Active surveillance with intensive mass screening is an effective method of identifying asymptomatic and latent cases of amebiasis in areas where it is endemic, such as an institution for adults with mental retardation.
Teaching the Cognitive Approach
Authors: Vial Theodore 
Published: May 2007

AbstractThe cognitive science of religion — relatively new and exciting to some and irritating and controversial to others in equal measure — is only now gaining recognition as a scholarly subject within religion. It does not come with an oral tradition of what texts are the key ones, what groundwork must be laid to make them comprehensible, or what strategies allow a teacher to make them accessible to students. All the reflective questions demanded of teachers as they prepare a syllabus are unavoidable as they consider adding a cognitive approach. This chapter explores the particular issue of how religious experiences become historical-cultural traditions. To do this the author equips his students with a stimulating theoretical immersion, while offering a frank discussion of what worked and what did not.
Domesticity and Difference/Women and Men: Religious Life in Medieval Tamilnadu
Authors: Orr Leslie C. 
Published: May 2007

AbstractThis chapter explores whether a domestic religious orientation, engaged with the personal and the particular, can be observed in the context of precolonial South India. It focuses on the period between the 9th to 13th centuries in the part of India known today as Tamilnadu. The chapter draws on the resources provided by the thousands of inscriptions written in the Tamil language and engraved in stone on the walls of Hindu and Jain temples during this period. These inscriptions record actions, particularly the making of gifts to temples by a wide variety of people. It is argued that although men's and women's activities recorded on temple walls had distinctive colorings, the contexts, roles, and motives for these actions were overlapping and often congruent.
Profiles in Diversity
Authors: Foley Michael W. , Hoge Dean R. 
Published: May 2007

AbstractRecent immigrants to the United States differ from the last great wave of immigrants in their countries of origin and socio-economic diversity. Immigration to the Washington, D.C. area differs from national patterns in relative geographic dispersal, the wide range of immigrant groups, and the presence of large proportions of immigrants from El Salvador, Africa, Asia, and the Muslim world. This chapter profiles the new immigration nationally and in the Washington, D.C. area, and offers a brief profile of each of the immigrant religious traditions analyzed here: West African Protestants and Catholics; Chinese Protestants and Catholics from Taiwan, the mainland, and the larger Chinese diaspora; Hindus and Sikhs from India; Korean Protestants and Catholics; Muslims; and Salvadoran Protestants and Catholics.
Defining Art, Creating the Canon
Authors: Crowther Paul 
Published: May 2007

AbstractWhat is art; why should we value it; and what allows us to say that one work is better than another? Traditional answers have emphasized aesthetic form; but this has been challenged by Institutional definitions of art and postmodern critique. The idea of distinctively artistic value based on aesthetic criteria is at best doubted, and at worst, rejected. This book champions such notions. It restores the mimetic definition of art on the basis of factors which traditional answers neglect, namely the conceptual link between art's aesthetic value and ‘non-exhibited’ epistemological and historical relations. These factors converge on an expanded notion of the artistic image (a notion which can even encompass music, abstract art, and some Conceptual idioms). The image's style serves to interpret its subject-matter. If this style is original (in comparative historical terms) it can manifest that special kind of aesthetic unity which we call art. Appreciation of this involves a heightened interaction of capacities (such as imagination and understanding), which are basic to knowledge and personal identity. By negotiating these factors, it is possible to define art and its canonic dimensions objectively, and to show that aforementioned sceptical alternatives are incomplete and self-contradictory.