1,306 research outputs found
Particle production in the outflow of a midlatitude storm
The concentrations of atmospheric gases and condensation nuclei (CN) or aerosol in the outflow of a storm were measured aboard a NASA DC-8 aircraft, as described in a companion paper [Twohy et al., 2002]. The data are used here to study the production of the aerosol. Major fluctuations in CN concentration are observed, in correlation with gas-phase species, but these are shown to arise as the result of the mixing of two distinct air masses. It is deduced that the CN originated in a storm outflow air mass and that its concentration before mixing was approximately uniform over a flight distance of about 200 km. The formation of the aerosol by nucleation followed by growth and coagulation is analyzed assuming that it consists of water and sulphuric acid produced locally by the oxidation of SO2. The analysis uses analytic models, and it is concluded that a 5 min burst of nucleation was followed by growth and coagulation over a period of about 5 hours. Both the mass and number concentrations of the observed aerosol can be reproduced by this analysis within a timescale consistent with that of the storm. The final number concentration is very insensitive to the initial SO2 concentration
Protocol for the INFORMED (Individualised Patient Care and Treatment for Maternal Diabetes) Study: a randomised controlled trial embedded within routine care
Introduction Diabetes in pregnancy presents a unique physiological challenge to manage glycaemia while maintaining adequate nourishment for the growing fetus. Women with diabetes who become pregnant are at greater risk of adverse maternal and newborn outcomes, compared with women without diabetes. Evidence suggests that control of (postprandial) glycaemia is key to manage maternal and offspring health but it is not yet clear (1) how diet and lifestyle moderate these shifts across the full duration of pregnancy or (2) what aspects of maternal and offspring health are associated with dysglycaemia.
Methods and analysis To investigate these gaps, a cross-over randomised clinical trial has been embedded within routine clinical care. Seventy-six pregnant women in their first trimester with type 1 or type 2 diabetes (with or without medication) attending their routine antenatal appointments at National Health Service (NHS) Leeds Teaching Hospitals will be recruited. Following informed consent, data on women’s health, glycaemia, pregnancy and delivery will be shared by the NHS with researchers. At each visit in the first (10–12 weeks), second (18–20 weeks) and third (28–34 weeks) trimester, participants will be asked for consent to: (1) lifestyle and diet questionnaires, (2) blood for research purposes and (3) analysis of urine collected at clinical visits. Additionally, participants will be asked to consume two blinded meals in duplicate in second and third trimester. Glycaemia will be assessed by continuous glucose monitoring as part of routine care. The primary outcome is the effect of experimental meals (high vs low protein) on postprandial glycaemia. Secondary outcomes include (1) the association between dysglycaemia and maternal and newborn health, and (2) the association between maternal metabolic profiles in early pregnancy with dysglycaemia in later pregnancy.
Ethics and dissemination The Leeds East Research Ethics Committee and NHS (REC: 21/NE/0196) approved the study. Results will be published in peer-reviewed journals and disseminated to participants and the wider public.
Trial registration number ISRCTN57579163
Uterine mullerian adenosarcoma with sarcomatous overgrowth fatal recurrence within two weeks of diagnosis: a case report
Mullerian adenosarcoma with sarcomatous overgrowth (MASO) is a rare variant of uterine sarcomas, associated with postoperative recurrence, metastases and a fatal outcome. The mean age at diagnosis is 54.5 years. A 37-year-old nullipara presented with irregular vaginal bleeding, a normal pelvic examination, and an initially negative ultrasound. Repeat ultrasound one month later revealed an 11-cm heterogeneous pelvic mass. She underwent total abdominal hysterectomy and bilateral salpingo-oophorectomy. Pathology confirmed uterine MASO. Computed tomography 2 weeks postoperatively showed a huge mass compatible with recurrence. Patient died 2 weeks later. MASO is rarely diagnosed in women in their 4th decade. This case stresses that these aggressive tumors should be considered in the differential of patients with vaginal bleeding and pelvic masses irrespective of their age
Extragenital MĂĽllerian adenosarcoma with pouch of Douglas location
Background: Of all female genital tract tumors, 1-3% are stromal malignancies. In 8-10% of cases, these are represented by Mullerian adenosarcoma an extremely rare tumor characterized by a stromal component of usually low-grade malignancy and by a benign glandular epithelial component. Variant that arises in the pouch of Douglas is scarcely mentioned in the medical literature.Case Presentation: A 49-year-old para-0 woman, was seen at our OB/GYN-UNIT because she complained vaguely of pelvic pain. She had a mass of undefined nature in the pouch of Douglas. A simple excision of the mass showed low-grade Mullerian adenosarcoma with areas of stromal overgrowth. One and a half year after surgery, at another hospital, a mass was detected in the patient's posterior vaginal fornix and removed surgically. Six months later she came back to our observation with vaginal bleeding and mass in the vaginal fornix. We performed radical surgery. The pathological examination showed recurrent adenosarcoma. Surgical treatment was supplemented by radiation therapy.Conclusions: The case of Mullerian adenosarcoma reported here is the third known so far in the literature that was located in the pouch of Douglas. To date, only two other such cases have been reported, including one resulting from neoplastic degeneration of an endometriotic cyst
Interleukin-1β sequesters hypoxia inducible factor 2α to the primary cilium.
BACKGROUND: The primary cilium coordinates signalling in development, health and disease. Previously we have shown that the cilium is essential for the anabolic response to loading and the inflammatory response to interleukin-1β (IL-1β). We have also shown the primary cilium elongates in response to IL-1β exposure. Both anabolic phenotype and inflammatory pathology are proposed to be dependent on hypoxia-inducible factor 2 alpha (HIF-2α). The present study tests the hypothesis that an association exists between the primary cilium and HIFs in inflammatory signalling. RESULTS: Here we show, in articular chondrocytes, that IL-1β-induces primary cilia elongation with alterations to cilia trafficking of arl13b. This elongation is associated with a transient increase in HIF-2α expression and accumulation in the primary cilium. Prolyl hydroxylase inhibition results in primary cilia elongation also associated with accumulation of HIF-2α in the ciliary base and axoneme. This recruitment and the associated cilia elongation is not inhibited by blockade of HIFα transcription activity or rescue of basal HIF-2α expression. Hypomorphic mutation to intraflagellar transport protein IFT88 results in limited ciliogenesis. This is associated with increased HIF-2α expression and inhibited response to prolyl hydroxylase inhibition. CONCLUSIONS: These findings suggest that ciliary sequestration of HIF-2α provides negative regulation of HIF-2α expression and potentially activity. This study indicates, for the first time, that the primary cilium regulates HIF signalling during inflammation
Geographical information system and predictive risk maps of urinary schistosomiasis in Ogun State, Nigeria
<p>Abstract</p> <p>Background</p> <p>The control of urinary schistosomiasis in Ogun State, Nigeria remains inert due to lack of reliable data on the geographical distribution of the disease and the population at risk. To help in developing a control programme, delineating areas of risk, geographical information system and remotely sensed environmental images were used to developed predictive risk maps of the probability of occurrence of the disease and quantify the risk for infection in Ogun State, Nigeria.</p> <p>Methods</p> <p>Infection data used were derived from carefully validated morbidity questionnaires among primary school children in 2001–2002, in which school children were asked among other questions if they have experienced "blood in urine" or urinary schistosomiasis. The infection data from 1,092 schools together with remotely sensed environmental data such as rainfall, vegetation, temperature, soil-types, altitude and land cover were analysis using binary logistic regression models to identify environmental features that influence the spatial distribution of the disease. The final regression equations were then used in Arc View 3.2a GIS software to generate predictive risk maps of the distribution of the disease and population at risk in the state.</p> <p>Results</p> <p>Logistic regression analysis shows that the only significant environmental variable in predicting the presence and absence of urinary schistosomiasis in any area of the State was Land Surface Temperature (LST) (B = 0.308, p = 0.013). While LST (B = -0.478, p = 0.035), rainfall (B = -0.006, p = 0.0005), ferric luvisols (B = 0.539, p = 0.274), dystric nitosols (B = 0.133, p = 0.769) and pellic vertisols (B = 1.386, p = 0.008) soils types were the final variables in the model for predicting the probability of an area having an infection prevalence equivalent to or more than 50%. The two predictive risk maps suggest that urinary schistosomiasis is widely distributed and occurring in all the Local Government Areas (LGAs) in State. The high-risk areas (≥ 50% prevalence) however, are confined to scatter foci in the north western part of the State. The model also estimated that 98.99% of schools aged children (5–14 years) are living in areas suitable for urinary schistosomiasis transmission and are at risk of infection.</p> <p>Conclusion</p> <p>The risk maps developed will hopefully be useful to the state health officials, by providing them with detailed distribution of urinary schistosomiasis, help to delineate areas for intervention, assesses population at risk thereby helping in optimizing scarce resources.</p
A comparative analysis of contraceptive use in Africa: evidence from DHS
The aim of this article is to show a comparative analysis of contraceptive use in areas of traditionally high
fertility that have gone through profound changes. Data have been taken from the latest Demographic and
Health Surveys (DHS). Logistic regression models were adopted for four selected representative countries,
namely Egypt, Mali, Namibia and Niger. There were two selection criteria: data should be recent, and selected
countries should have high (Egypt 57.4%; Namibia 46.4%) or low (Mali 7.5%; Niger 10.0%) contraceptive use.
The probability of using contraception when a woman has had one to four children is 2.4 times higher than
when they have had no children. Contraception data are always gathered at a point of time, but crosssectional
data are not sufficient to understand all the mechanisms hidden behind contraceptive use. Different
contraceptive behaviours need good estimation tools to develop specific family planning programmes.Web of Scienc
Stringy Stability of Charged Dilaton Black Holes with Flat Event Horizon
Electrically charged black holes with flat event horizon in anti-de Sitter
space have received much attention due to various applications in Anti-de
Sitter/Conformal Field Theory (AdS/CFT) correspondence, from modeling the
behavior of quark-gluon plasma to superconductor. Crucial to the physics on the
dual field theory is the fact that when embedded in string theory, black holes
in the bulk may become vulnerable to instability caused by brane
pair-production. Since dilaton arises naturally in the context of string
theory, we study the effect of coupling dilaton to Maxwell field on the
stability of flat charged AdS black holes. In particular, we study the
stability of Gao-Zhang black holes, which are locally asymptotically anti-de
Sitter. We find that for dilaton coupling parameter > 1, flat black
holes are stable against brane pair production, however for 0 < < 1,
the black holes eventually become unstable as the amount of electrical charges
is increased. Such instability however, behaves somewhat differently from that
of flat Reissner-Nordstr\"om black holes. In addition, we prove that the
Seiberg-Witten action of charged dilaton AdS black hole of Gao-Zhang type with
flat event horizon (at least in 5-dimension) is always logarithmically
divergent at infinity for finite values of , and is finite and positive
in the case tends to infinity . We also comment on the robustness of
our result for other charged dilaton black holes that are not of Gao-Zhang
type.Comment: Fixed some confusions regarding whether part of the discussions
concern electrically charged hole or magnetically charged one. No changes to
the result
Evidence of two lineages of the dengue vector Aedes aegypti in the Brazilian Amazon, based on mitochondrial DNA ND4 gene sequences
Genetic variation was estimated in ten samples populations of Aedes aegypti from the Brazilian Amazon, by using a 380 bp fragment of the mitochocondrial NADH dehydrogenase subunit 4 (ND4) gene. A total of 123 individuals were analyzed, whereby 13 haplotypes were found. Mean genetic diversity was slightly high (h = 0.666 ± 0.029; π = 0.0115 ± 0.0010). Two AMOVA analyses indicated that most of the variation (~70%-72%) occurred within populations. The variation found among and between populations within the groups disclosed lower, but even so, highly significant values. FST values were not significant in most of the comparisons, except for the samples from Pacaraima and Rio Branco. The isolation by distance (IBD) model was not significant (r = 0.2880; p = 0.097) when the samples from Pacaraima and Rio Branco were excluded from the analyses, this indicating that genetic distance is not related to geographic distance. This result may be explained either by passive dispersal patterns (via human migrations and commercial exchange) or be due to the recent expansion of this mosquito in the Brazilian Amazon. Phylogenetic relationship analysis showed two genetically distinct groups (lineages) within the Brazilian Amazon, each sharing haplotypes with populations from West Africa and Asia
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