954 research outputs found
Response to “Comment to “The transition on North America from the warm humid Pliocene to the glaciated Quaternary traced by eolian dust deposition at a benchmark North Atlantic Ocean drill site, by David Lang et al. Quaternary Science Reviews 93: 125-141””
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Growth of infants born to HIV-positive mothers fed a whey-adapted acidified starter formula with prebiotics and nucleotides
Objectives: The objectives of this study were to evaluate whether infants born to known HIV-positive mothers, but who were not themselves infected with HIV and who were fed a chemically acidified starter formula with prebiotics with or without nucleotides during their first six months, displayed growth rates equal to uninfected infants fed a chemically acidified starter formula without prebiotics or nucleotides.Design: The design was a multi-centre, double-blinded randomised controlled trial.Setting: The study was carried out in four academic hospitals, three in Johannesburg and one in Cape Town, South Africa.Subjects and intervention: The subjects were newborn infants born to consenting HIV-positive women who had previously decided not to breast feed. The infants were randomised to receive one of three milk formulas. The intervention comprised chemically acidified formula without prebiotics or nucleotides, with prebiotics only, or with prebiotics and nucleotides.Outcome measures: The outcome measures were the growth parameters through the first six months of life.Results: Of the 150 randomised infants, 50 did not complete the study and 16 (12.8% of those tested) were infected with HIV, leaving 84 infants available for analysis. All three formulas were tolerated well, with no differences in growth parameters seen with the addition of prebiotics and nucleotides. The growth rates of the study infants up to the age of six months were very good, showing an increase in Z-scores from negative values at the time of enrolment in the first week after birth to around zero for length and > 0.5 for weight.Conclusions: The three chemically acidified formulas were tolerated well and resulted in good growth over the first six months of life. No benefits were seen with the addition of prebiotics or nucleotides. The growth rates were similar to those found in previous studies of ours on biologically acidified formulas. The chemical acidification of infant formulas appears to be a realistic alternative to biological acidification should an acidified formula be required.Keywords: milk formula; acidification; probiotics; nucleotides; infant growt
On the Relation Between Jupiter's Aurora and the Dawnside Current Sheet
Jupiter's auroral emission is a spectacular phenomenon that provides insight into energy release processes related to the coupling of its magnetosphere and ionosphere. This energy release is influenced by solar wind conditions. Using joint observations from Juno and the Hubble Space Telescope (HST), we statistically investigate the relationship between auroral power and current sheet variations under different solar wind conditions. In this study, we reveal that during global main auroral brightening events that are closely connected to solar wind compressions, the dawn side current sheet is substantially thinner than during times when a quiet auroral morphology is present. Furthermore, the total current intensity in the current sheet is found to increase under solar wind compression conditions compared to the quiet period. These findings provide important observational evidence for how magnetospheric dynamics driven by solar wind behavior affect auroral activity, deepening our understanding of the coupling between Jupiter's magnetosphere and ionosphere
North Atlantic mid-latitude surface-circulation changes through the Plio-Pleistocene intensification of northern hemisphere glaciation
This is the final version. Available from American Geophysical Union (AGU) / Wiley via the DOI in this record.All new data presented are available at
https://doi.pangaea.de/10.1594/PANGAEA.892805The North Atlantic Current (NAC) transports warm salty water to high northern latitudes, with important repercussions for ocean circulation and global climate. A southward displacement of the NAC and Subarctic Front, which separate subpolar and subtropical water masses, is widely suggested for the last glacial maximum (LGM) and may have acted as a positive feedback in glacial expansion at this time. However, the role of the NAC during the intensification of northern hemisphere glaciation (iNHG) ~3.5 to 2.5 Ma, is less clear. Here, we present new records from IODP Site U1313 (41°N) spanning ~2.8-2.4 Ma to trace the influence of Subarctic Front waters above this mid-latitude site. We reconstruct surface and permanent pycnocline temperatures and seawater δ18O using paired Mg/Ca-δ18O measurements on the planktic foraminifers Globigerinoides ruber and Globorotalia crassaformis, and determine abundances of the subpolar foraminifer Neogloboquadrina atlantica. We find that the first significant glacial incursions of Subarctic Front surface waters above Site U1313 did not occur until ~2.6 Ma. At no time during our study interval was (sub)surface reorganisation in the mid-latitude North Atlantic analogous to the LGM. Our findings suggest that LGM-like processes sensu stricto cannot be invoked to explain interglacial-glacial cycle amplification during iNHG. They also imply that increased glacial productivity at Site U1313 during iNHG was not only driven by southward deflections of the Subarctic Front. We suggest nutrient injection from cold-core eddies and enhanced glacial dust delivery may have played additional roles in increasing export productivity in the mid-latitude North Atlantic from 2.7 Ma.Funding for this research
was provided by IODP France (CTB) and the German Research Foundation (DFG) (grant OF 2544/2
to OF). IB is grateful to the UK IODP for financial support for shipboard and post-cruise
participation in IODP Exp. 306. CTB, KT, TDG, LV, CS, and ME acknowledge OSU Pythéas.
MMR acknowledges support by the USGS Land Change Science Program. Any use of trade, firm, or
product names is for descriptive purposes only and does not imply endorsement by the U.S.
Government. PAW acknowledges NERC UK IODP NE/F00141X/1 and a Royal Society Wolfson
Merit Award
Characterization of Polymorphic Microsatellites in the Giant Bulldog Ant, Myrmecia brevinoda and the Jumper Ant, M. pilosula
The ant genus Myrmecia Fabricius (Hymenoptera: Formicidae) is endemic to Australia and New Caledonia, and has retained many biological traits that are considered to be basal in the family Formicidae. Here, a set of 16 dinucleotide microsatellite loci were studied that are polymorphic in at least one of the two species of the genus: the giant bulldog ant, M. brevinoda Forel, and the jumper ant, M. pilosula Smith; 13 are novel loci and 3 are loci previously published for the genus Nothomyrmecia Clark (Hymenoptera: Formicidae). In M. brevinoda, the total of 12 polymorphic microsatellites yielded a total of 125 alleles, ranging from 3 to 18 with an average of 10.42 per locus; the observed and expected heterozygosities ranged from 0.4000 to 0.9000 and from 0.5413 to 0.9200, respectively. In M. pilosula, the 9 polymorphic loci yielded a total of 67 alleles, ranging from 3 to 12 with an average of 7.44 per locus; the observed and expected heterozygosities ranged from 0.5625 to 0.9375 and from 0.4863 to 0.8711, respectively. Five loci were polymorphic in both target species. In addition, 15 out of the 16 loci were successfully amplified in M. pyriformis. These informative microsatellite loci provide a powerful tool for investigating the population and colony genetic structure of M. brevinoda and M. pilosula, and may also be applicable to a range of congeners considering the relatively distant phylogenetic relatedness between M. pilosula and the other two species within the genus Myrmecia
A demographic and epidemiological study of a Mexican chiropractic college public clinic
<p>Abstract</p> <p>Background</p> <p>Descriptive studies of chiropractic patients are not new, several have been performed in the U.S., Australia, Canada, and Europe. None have been performed in a Latin American country. The purpose of this study is to describe the patients who visited a Mexican chiropractic college public clinic with respect to demographics and clinical characteristics.</p> <p>Methods</p> <p>This study was reviewed and approved by the IRB of Parker College of Chiropractic and the Universidad Estatal del Valle de Ecatepec (UNEVE). Five hundred patient files from the UNEVE public clinic from May 2005 to May 2007 were selected from an approximate total number of 3,700. Information was collected for demographics, chief complaints, associated complaints, and previous care sought.</p> <p>Results</p> <p>The sample comprised 306 (61.2%) female. Most files (44.2%) were in the age range of 40–59 years (mean of 43.4 years). The most frequent complaints were lumbar pain (29.2%) and extremity pain (28.0%), most commonly the knee. Most (62.0%) described their complaints as greater than one year. Trauma (46.6%) was indicated as the initial cause. Mean VAS score was 6.26/10 with 20% rated at 8/10.</p> <p>Conclusion</p> <p>Demographic results compared closer to studies conducted with private clinicians (females within the ages of 40–59). The primary complaint and duration was similar to previous studies (low back pain and chronic), except in this population the cause was usually initiated by trauma. The most striking features were the higher number of extremity complaints and the marked increased level of VAS score (20% rated as 8/10).</p
Early star-forming galaxies and the reionization of the Universe
Star forming galaxies represent a valuable tracer of cosmic history. Recent
observational progress with Hubble Space Telescope has led to the discovery and
study of the earliest-known galaxies corresponding to a period when the
Universe was only ~800 million years old. Intense ultraviolet radiation from
these early galaxies probably induced a major event in cosmic history: the
reionization of intergalactic hydrogen. New techniques are being developed to
understand the properties of these most distant galaxies and determine their
influence on the evolution of the universe.Comment: Review article appearing in Nature. This posting reflects a submitted
version of the review formatted by the authors, in accordance with Nature
publication policies. For the official, published version of the review,
please see http://www.nature.com/nature/archive/index.htm
Quality gap of educational services in viewpoints of students in Hormozgan University of medical sciences
<p>Abstract</p> <p>Background</p> <p>Higher education is growing fast and every day it becomes more and more exposed to globalization processes. The aim of this study was to determine the quality gap of educational services by using a modified SERVQUAL instrument among students in Hormozgan University of Medical Sciences.</p> <p>Methods</p> <p>A cross-sectional study was carried out at Hormozgan University of Medical Sciences in 2007. In this study, a total of 300 students were selected randomly and asked to complete a questionnaire that was designed according to SERVQUAL methods. This questionnaire measured students' perceptions and expectations in five dimensions of service that consists of assurance, responsiveness, empathy, reliability and tangibles. The quality gap of educational services was determined based on differences between students' perceptions and expectations.</p> <p>Results</p> <p>The results demonstrated that in each of the five SERVQUAL dimensions, there was a negative quality gap. The least and the most negative quality gap means were in the reliability (-0.71) and responsiveness (-1.14) dimensions respectively. Also, there were significant differences between perceptions and expectations of students in all of the five SERVQUAL dimensions (p < 0.001).</p> <p>Conclusion</p> <p>Negative quality gaps mean students' expectations exceed their perceptions. Thus, improvements are needed across all five dimensions.</p
Strong Ultraviolet Pulse From a Newborn Type Ia Supernova
Type Ia supernovae are destructive explosions of carbon oxygen white dwarfs.
Although they are used empirically to measure cosmological distances, the
nature of their progenitors remains mysterious, One of the leading progenitor
models, called the single degenerate channel, hypothesizes that a white dwarf
accretes matter from a companion star and the resulting increase in its central
pressure and temperature ignites thermonuclear explosion. Here we report
observations of strong but declining ultraviolet emission from a Type Ia
supernova within four days of its explosion. This emission is consistent with
theoretical expectations of collision between material ejected by the supernova
and a companion star, and therefore provides evidence that some Type Ia
supernovae arise from the single degenerate channel.Comment: Accepted for publication on the 21 May 2015 issue of Natur
Rates and risks for prolonged grief disorder in a sample of orphaned and widowed genocide survivors
<p>Abstract</p> <p>Background</p> <p>The concept of Prolonged Grief Disorder (PGD) has been defined in recent years by Prigerson and co-workers, who have developed and empirically tested consensus and diagnostic criteria for PGD. Using these most recent criteria defining PGD, the aim of this study was to determine rates of and risks for PGD in survivors of the 1994 Rwandan genocide who had lost a parent and/or the husband before, during or after the 1994 events.</p> <p>Methods</p> <p>The PG-13 was administered to 206 orphans or half orphans and to 194 widows. A regression analysis was carried out to examine risk factors of PGD.</p> <p>Results</p> <p>8.0% (<it>n </it>= 32) of the sample met criteria for PGD with an average of 12 years post-loss. All but one person had faced multiple losses and the majority indicated that their grief-related loss was due to violent death (70%). Grief was predicted mainly by time since the loss, by the violent nature of the loss, the severity of symptoms of posttraumatic stress disorder (PTSD) and the importance given to religious/spiritual beliefs. By contrast, gender, age at the time of bereavement, bereavement status (widow versus orphan), the number of different types of losses reported and participation in the funeral ceremony did not impact the severity of prolonged grief reactions.</p> <p>Conclusions</p> <p>A significant portion of the interviewed sample continues to experience grief over interpersonal losses and unresolved grief may endure over time if not addressed by clinical intervention. Severity of grief reactions may be associated with a set of distinct risk factors. Subjects who lose someone through violent death seem to be at special risk as they have to deal with the loss experience as such and the traumatic aspects of the loss. Symptoms of PTSD may hinder the completion of the mourning process. Religious beliefs may facilitate the mourning process and help to find meaning in the loss. These aspects need to be considered in the treatment of PGD.</p
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