Superstring Cosmology

Aspects of superstring cosmology are reviewed with an emphasis on the cosmological implications of duality symmetries in the theory. The string effective actions are summarized and toroidal compactification to four dimensions reviewed. Global symmetries that arise in the compactification are discussed and the duality relationships between the string effective actions are then highlighted. Higher-dimensional Kasner cosmologies are presented and interpreted in both string and Einstein frames, and then given in dimensionally reduced forms. String cosmologies containing both non-trivial Neveu-Schwarz/Neveu-Schwarz and Ramond-Ramond fields are derived by employing the global symmetries of the effective actions. Anisotropic and inhomogeneous cosmologies in four-dimensions are also developed. The review concludes with a detailed analysis of the pre-big bang inflationary scenario. The generation of primordial spectra of cosmological perturbations in such a scenario is discussed. Possible future directions offered in the Horava-Witten theory are outlined.Comment: 161 pages, latex with epsf, 15 figures. Minor changes, additional references and figures. Version to appear in Physics Report

Crónicas

Comentario y reseña de los siguientes eventos: Congreso Nacional “Proyecciones disciplinares del Humanismo” (La Plata, 17 y 18 de mayo de 2018); VI Jornadas Internacionales de Historia Antigua (Córdoba, 22 a 24 de mayo de 2018); Curso Internacional del Centro de Estudios Latinos “Naturaleza e historia: piedras, templos y estatuas” (La Plata, 11 y 12 de junio de 2018); Segundas Jornadas Nacionales de Historia de la Antigüedad Tardía (La Rioja, 12 a 14 de junio de 2018); VIII Coloquio Internacional “Cartografías del yo en el mundo antiguo. Estrategias de su textualización” (La Plata, 26 a 29 de junio de 2018); Curso Internacional del Centro de Estudios Latinos “Pietas y guerra civil” (La Plata, 5 y 6 de julio de 2018); International Colloquium “Statues in Roman Religion” / Colóquio Internacional “Estátuas na Religião Romana” (Rio de Janeiro, 11 a 13 de julio 2018); XXV Simposio Nacional de Estudios Clásicos. I Congreso Internacional sobre el Mundo Clásico “Migraciones, desplazamientos, conflictos en el mundo antiguo” (Buenos Aires, 31 de julio a 3 de agosto de 2018); V Jornadas de Creación y Crítica Literaria (Buenos Aires, 6 y 7 de septiembre de 2018); VII Jornadas de Graduadxs e Investigadores en formación de la Facultad de Humanidades y Ciencias de la Educación “Investigación, docencia y extensión a 100 años de la Reforma Universitaria” (La Plata, 24 a 26 de octubre de 2018).Facultad de Humanidades y Ciencias de la Educació

Crónicas

Comentario y reseña de los siguientes eventos: Congreso Nacional “Proyecciones disciplinares del Humanismo” (La Plata, 17 y 18 de mayo de 2018); VI Jornadas Internacionales de Historia Antigua (Córdoba, 22 a 24 de mayo de 2018); Curso Internacional del Centro de Estudios Latinos “Naturaleza e historia: piedras, templos y estatuas” (La Plata, 11 y 12 de junio de 2018); Segundas Jornadas Nacionales de Historia de la Antigüedad Tardía (La Rioja, 12 a 14 de junio de 2018); VIII Coloquio Internacional “Cartografías del yo en el mundo antiguo. Estrategias de su textualización” (La Plata, 26 a 29 de junio de 2018); Curso Internacional del Centro de Estudios Latinos “Pietas y guerra civil” (La Plata, 5 y 6 de julio de 2018); International Colloquium “Statues in Roman Religion” / Colóquio Internacional “Estátuas na Religião Romana” (Rio de Janeiro, 11 a 13 de julio 2018); XXV Simposio Nacional de Estudios Clásicos. I Congreso Internacional sobre el Mundo Clásico “Migraciones, desplazamientos, conflictos en el mundo antiguo” (Buenos Aires, 31 de julio a 3 de agosto de 2018); V Jornadas de Creación y Crítica Literaria (Buenos Aires, 6 y 7 de septiembre de 2018); VII Jornadas de Graduadxs e Investigadores en formación de la Facultad de Humanidades y Ciencias de la Educación “Investigación, docencia y extensión a 100 años de la Reforma Universitaria” (La Plata, 24 a 26 de octubre de 2018).Facultad de Humanidades y Ciencias de la Educació

Association between diabetes mellitus and active tuberculosis: A systematic review and meta-analysis.

The burgeoning epidemic of diabetes mellitus (DM) is one of the major global health challenges. We systematically reviewed the published literature to provide a summary estimate of the association between DM and active tuberculosis (TB). We searched Medline and EMBASE databases for studies reporting adjusted estimates on the TB-DM association published before December 22, 2015, with no restrictions on region and language. In the meta-analysis, adjusted estimates were pooled using a DerSimonian-Laird random-effects model, according to study design. Risk of bias assessment and sensitivity analyses were conducted. 44 eligible studies were included, which consisted of 58,468,404 subjects from 16 countries. Compared with non-DM patients, DM patients had 3.59-fold (95% confidence interval (CI) 2.25-5.73), 1.55-fold (95% CI 1.39-1.72), and 2.09-fold (95% CI 1.71-2.55) increased risk of active TB in four prospective, 16 retrospective, and 17 case-control studies, respectively. Country income level (3.16-fold in low/middle-vs. 1.73-fold in high-income countries), background TB incidence (2.05-fold in countries with >50 vs. 1.89-fold in countries with ≤50 TB cases per 100,000 person-year), and geographical region (2.44-fold in Asia vs. 1.71-fold in Europe and 1.73-fold in USA/Canada) affected appreciably the estimated association, but potential risk of bias, type of population (general versus clinical), and potential for duplicate data, did not. Microbiological ascertainment for TB (3.03-fold) and/or blood testing for DM (3.10-fold), as well as uncontrolled DM (3.30-fold), resulted in stronger estimated association. DM is associated with a two- to four-fold increased risk of active TB. The association was stronger when ascertainment was based on biological testing rather than medical records or self-report. The burgeoning DM epidemic could impact upon the achievements of the WHO "End TB Strategy" for reducing TB incidence

VISTA Variables in the <i>Vía Láctea</i> (VVV): Halfway Status and Results

The VISTA Variables in the Vía Láctea (VVV) survey is one of six near-infrared ESO public surveys, and is now in its fourth year of observing. Although far from being complete, the VVV survey has already delivered many results, some directly connected to the intended science goals (detection of variable stars, microlensing events, new star clusters), others concerning more exotic objects, e.g., novae. Now, at the end of the fourth observing period, and comprising roughly 50% of the proposed observations, the status of the survey, as well some of results based on the VVV data, are presented.Facultad de Ciencias Astronómicas y Geofísica

VISTA Variables in the <i>Vía Láctea</i> (VVV): Halfway Status and Results

The VISTA Variables in the Vía Láctea (VVV) survey is one of six near-infrared ESO public surveys, and is now in its fourth year of observing. Although far from being complete, the VVV survey has already delivered many results, some directly connected to the intended science goals (detection of variable stars, microlensing events, new star clusters), others concerning more exotic objects, e.g., novae. Now, at the end of the fourth observing period, and comprising roughly 50% of the proposed observations, the status of the survey, as well some of results based on the VVV data, are presented.Facultad de Ciencias Astronómicas y Geofísica

The Airway Microbiota in Cystic Fibrosis: A Complex Fungal and Bacterial Community—Implications for Therapeutic Management

International audienceBackground Given the polymicrobial nature of pulmonary infections in patients with cystic fibrosis (CF), it is essential to enhance our knowledge on the composition of the microbial community to improve patient management. In this study, we developed a pyrosequencing approach to extensively explore the diversity and dynamics of fungal and prokaryotic populations in CF lower airways. Methodology and Principal Findings Fungi and bacteria diversity in eight sputum samples collected from four adult CF patients was investigated using conventional microbiological culturing and high-throughput pyrosequencing approach targeting the ITS2 locus and the 16S rDNA gene. The unveiled microbial community structure was compared to the clinical profile of the CF patients. Pyrosequencing confirmed recently reported bacterial diversity and observed complex fungal communities, in which more than 60% of the species or genera were not detected by cultures. Strikingly, the diversity and species richness of fungal and bacterial communities was significantly lower in patients with decreased lung function and poor clinical status. Values of Chao1 richness estimator were statistically correlated with values of the Shwachman-Kulczycki score, body mass index, forced vital capacity, and forced expiratory volume in 1 s (p = 0.046, 0.047, 0.004, and 0.001, respectively for fungal Chao1 indices, and p = 0.010, 0.047, 0.002, and 0.0003, respectively for bacterial Chao1 values). Phylogenetic analysis showed high molecular diversities at the sub-species level for the main fungal and bacterial taxa identified in the present study. Anaerobes were isolated with Pseudomonas aeruginosa, which was more likely to be observed in association with Candida albicans than with Aspergillus fumigatus

VISTA Variables in the Via Lactea (VVV): The public ESO near-IR variability survey of the Milky Way

We describe the public ESO near-IR variability survey (VVV) scanning the Milky Way bulge and an adjacent section of the mid-plane where star formation activity is high. The survey will take 1929 h of observations with the 4-m VISTA telescope during 5 years (2010–2014), covering ∼109 point sources across an area of 520 deg2, including 33 known globular clusters and ∼350 open clusters. The final product will be a deep near-IR atlas in five passbands (0.9–2.5 μm) and a catalogue of more than 106 variable point sources. Unlike single-epoch surveys that, in most cases, only produce 2-D maps, the VVV variable star survey will enable the construction of a 3-D map of the surveyed region using well-understood distance indicators such as RR Lyrae stars, and Cepheids. It will yield important information on the ages of the populations. The observations will be combined with data from MACHO, OGLE, EROS, VST, Spitzer, HST, Chandra, INTEGRAL, WISE, Fermi LAT, XMM-Newton, GAIA and ALMA for a complete understanding of the variable sources in the inner Milky Way. This public survey will provide data available to the whole community and therefore will enable further studies of the history of the Milky Way, its globular cluster evolution, and the population census of the Galactic Bulge and center, as well as the investigations of the star forming regions in the disk. The combined variable star catalogues will have important implications for theoretical investigations of pulsation properties of stars.Facultad de Ciencias Astronómicas y Geofísica

Knowledge of human papillomavirus vaccination: A multi-institution, cross-sectional study of allopathic and osteopathic medical students

Human papillomavirus (HPV) vaccination is a well-established and successful tool for preventing HPV-related cancers. However, vaccine uptake remains low, influenced by patient hesitancy around safety concerns and little opportunity to discuss the vaccine with trusted healthcare providers. We conducted a national, cross-sectional study of allopathic and osteopathic medical students regarding knowledge of HPV vaccination guidelines March-April 2021. Analysis sought to identify gaps in knowledge as well as demographic and academic correlates of knowledge. A total of 718 students participated (response rate = 50.8%). While 92.8% of participants identified the connection between HPV and cervical cancer, lower percentages associated HPV with vaginal/vulvar (67.7%), anal (63.3%), and penile (53.9%) cancers. Low percentages of participants correctly identified age of HPV vaccine eligibility (33.3%) and how many doses are needed for full protection (48.1%). This study identifies specific knowledge gaps in medical students’ training on HPV-related cancers and HPV vaccination guidelines. Through addressing these gaps, we may improve HPV vaccine uptake and decrease the incidence of HPV-related cancers

Knowledge of human papillomavirus vaccination: A multi-institution, cross-sectional study of allopathic and osteopathic medical students

Human papillomavirus (HPV) vaccination is a well-established and successful tool for preventing HPV-related cancers. However, vaccine uptake remains low, influenced by patient hesitancy around safety concerns and little opportunity to discuss the vaccine with trusted healthcare providers. We conducted a national, cross-sectional study of allopathic and osteopathic medical students regarding knowledge of HPV vaccination guidelines March-April 2021. Analysis sought to identify gaps in knowledge as well as demographic and academic correlates of knowledge. A total of 718 students participated (response rate = 50.8%). While 92.8% of participants identified the connection between HPV and cervical cancer, lower percentages associated HPV with vaginal/vulvar (67.7%), anal (63.3%), and penile (53.9%) cancers. Low percentages of participants correctly identified age of HPV vaccine eligibility (33.3%) and how many doses are needed for full protection (48.1%). This study identifies specific knowledge gaps in medical students’ training on HPV-related cancers and HPV vaccination guidelines. Through addressing these gaps, we may improve HPV vaccine uptake and decrease the incidence of HPV-related cancers