8,489 research outputs found
Astro-WISE processing of wide-field images and other data
Astro-WISE is the Astronomical Wide-field Imaging System for Europe. It is a
scientific information system which consists of hardware and software federated
over about a dozen institutes throughout Europe. It has been developed to
exploit the ever increasing avalanche of data produced by astronomical surveys
and data intensive scientific experiments in general.
The demo explains the architecture of the Astro-WISE information system and
shows the use of Astro-WISE interfaces. Wide-field astronomical images are
derived from the raw image to the final catalog according to the user's
request. The demo is based on the standard Astro-WISE guided tour, which can be
accessed from the Astro-WISE website.
The typical Astro-WISE data processing chain is shown, which can be used for
data handling for a variety of different instruments, currently 14, including
OmegaCAM, MegaCam, WFI, WFC, ACS/HST, etc.Comment: 4 pages, Procedings of ADASS XXI, ASP Conference Serie
Exposure of human renal proximal tubular cells to glucose leads to accumulation of type IV collagen and fibronectin by decreased degradation
Exposure of human renal proximal tubular cells to glucose leads to accumutation of type IV collagen and fibronectin by decreased degradation. Thickening and reduplication of the tubular basement membrane has been reported as an early event in diabetic nephropathy. In the current study we examined the effects of elevated D-glucose concentrations on human proximal tubular (HPTC) type IV collagen and fibronectin turnover. Incubation of confluent growth arrested HPTC with 25mM D-glucose led to accumulation of both type IV collagen and fibronectin. This effect was maximal at 48 hours and represented a sevenfold increase for fibronectin (N = 4, P = 0.04), and a threefold increase for type IV collagen (N = 3, P = 0.03) over cells exposed to 5mM D-glucose controls. This increase was not dependent on new gene transcription for either protein. Tissue inhibitor of metalloproteinases (TIMP 1 + TIMP 2) were induced following addition of 25mM D-glucose, but not when cells were exposed to 5mM D-glucose. Twenty-four hours after the addition of 25mM D-glucose there was an eightfold increase in TIMP 1 (P = 0.009, N = 4), and a tenfold increase in TIMP 2 levels (P = 0.003, N = 4), over the control values for both inhibitors. The increase in both TIMP 1 and TIMP 2 in response to 25mM D-glucose was abrogated in a dose dependent manner by the aldose reductase inhibitor sorbinil. Gelatin-substrate gel zymography showed increased activity of gelatinase A, but not of gelatinase B in response to the addition of 25mM D-glucose to HPTC. The induction of gelatinase A was accompanied by increased gelatinase A mRNA expression, which was inhibited both by protein kinase C (PKC) depletion using PMA pre-treatment, and by the addition of a PKC inhibitor. These data demonstrate that the glucose-induced accumulation of type IV collagen and fibronectin is unrelated to increased gene transcription, but may involve alterations in the degradative pathway of these basement membrane constituents. Furthermore, the data demonstrate that glucose may simultaneously activate two intracellular pathways (the polyol pathway and a PKC dependent activation pathway), which are involved in mediating separate, complementary effects on cell function
Quality and acceptability of routine "opt-out" HIV testing in antenatal services in the Kassena-Nankana district of northern Ghana
Magister Public Health - MPHSince the advent of the HIV pandemic, efforts have been made to find and implement interventions to reduce the risk of transmission of the infection in various risk groups. Mother to child transmission is responsible for a great majority of childhood HIV infections. Interventions have been developed which reduce considerably the risk of mother to child transmission to babies born to women who are infected. To be able to access these interventions, pregnant women first have to know their status by being tested at antenatal clinics. Initial testing protocols in most countries were based on the opt-in, client-initiated approach. However, in many countries, this did not result in many women getting tested and being able to access interventions. Accordingly, many countries have now adopted the routine opt-out approach as a way of increasing testing rates among women attending antenatal clinics. Ghana has had a PMTCT programme since 2004 initially based on opt-in testing. In 2007, there was a change in this testing regimen to the opt-out approach. The aim of this study was to assess the quality, acceptability and factors influencing the acceptability of the use of routine verbal opt-out strategy for HIV testing during pregnancy for women attending antenatal clinics in the Kassena-Nankana district of northern Ghana. A cross-sectional analytical study design was used in this study. The study was conducted in the Kassena-Nankana district of northern Ghana using a structured questionnaire in face to face exit interviews with pregnant women after they had completed their first antenatal clinic visit. A total of 251 women aged between 15-49 years were interviewed after informed consent had been obtained from them. Data was captured with Epidata and analysed with EpiInfo. Cross-tabulations and logistic regression analyses were done. Of the 251 respondents who were interviewed in this survey, 85% of them were aware of MTCT, 82% knew at least one PMTCT strategy, 92% felt they had experienced good quality counselling that day at the ANC and 81% thought that the opt-out testing was acceptable. The perception of the women in the study about the quality of counselling they were given, their exposure to radio and their ethnicity were significantly associated with their acceptability of opt-out testing for HIV. While majority of the respondents felt that the quality of the counselling they received was good and a majority also felt that the opt-out strategy was acceptable, there were concerns about the quality of counselling provided. Recommendations include the need to improve counselling practices in the antenatal clinics by providing more structured information to the women. The District Health Management Team also needs to provide more information to people in the communities about PMTCT using radio as a medium
The drag on a microcantilever oscillating near a wall
Motivated by devices such as the atomic force microscope, we compute the drag
experienced by a cylindrical body of circular or rectangular cross-section oscillating
at small amplitude near a plane wall. The body lies parallel to the wall and oscillates
normally to it; the body is assumed to be long enough for the dominant flow to be
two-dimensional. The flow is parameterized by a frequency parameter γ² (a Strouhal
number) and the wall–body separation Δ (scaled on body radius). Numerical solutions
of the unsteady Stokes equations obtained using finite-difference computations in
bipolar coordinates (for circular cross-sections) and boundary-element computations
(for rectangular cross-sections) are used to determine the drag on the body. Numerical
results are validated and extended using asymptotic predictions (for circular cylinders)
obtained at all extremes of (γ, Δ)-parameter space. Regions in parameter space for
which the wall has a significant effect on drag are identified.R. J. Clarke, S. M. Cox, P. M. Williams and O. E. Jense
Computational simulation of mechanism and isotope effects on acetal heterolysis as a model for glycoside hydrolysis.
DFT calculations for the equilibrium isotope effect for deuterium substitution at the anomeric centre Cα in 2-(p-nitrophenoxy)tetrahydropyran with continuum solvation show significant variation in the range of relative permittivity 2 ≤ ε ≤ 10. One-dimensional scans of potential energy (with implicit solvation by water) or of free energy (from QM/MM potentials of mean force with explicit aqueous solvation with a hybrid AM1/OPLS method) for heterolysis of the bond between Cα and the nucleofuge do not show a transition state. A two-dimensional free-energy surface that considers also the distance between Cα and a nucleophilic water indicates a pre-association DN*ANint‡ mechanism with a transition state involving nucleophilic attack upon an ion-pair intermediate, and this is supported by good agreement between the mean values of the calculated and experimental α-D KIEs. However, the magnitudes of the standard deviations about the mean values for the making and breaking C–O bonds suggest that the transition state is rather plastic, with Cα–Onu ≈ 2 ± 0.4 Å and Cα–Olg ≈ 3 ± 0.5 Å. Not only is nucleophilic solvent assistance necessary, but there is also evidence for electrophilic assistance through specific hydrogen bonding to the nucleofuge
EMERGING TRENDS IN PLANNING AND ADMINISTRATION OF HIGHER EDUCATION PROGRAMMES IN NIGERIA
Educational planning and administration trends in higher institutions across the world continue to evolve due to the new discoveries, research outcomes, funding, technological and industrial advancement of the institutions. Administrators of higher education programmes in Nigeria are saddled with the task of developing appropriate administrative policies whose implementation must be in line with the sustainable development of the 21st century academia. This paper discussed the extent to which institutions of higher learning in a developing nation like Nigeria should plan and administer higher education programmes, as well as operate to achieve academic excellence, high standard, international ranking and effective administration. The authors equally provided suggestions for improvement to stakeholders that may require such transformation.  Article visualizations
Application of three-dimensional fault stress models for assessment of fault stability for CO2 storage sites
Carbon Capture and Storage (CCS) is a key technology for a low-carbon energy future and will have an important role on the economic future of the UK Continental Shelf (UKCS). The East Irish Sea Basin (EISB) is a prospective area for CCS in the western UKCS. 3D seismic from the EISB were used in this study to characterise the fault network and potential fault reactivation risks associated with CO2 injection. Two main structural domains are present: a Northern domain with NW-SE faults, and a Southern domain with faults following a N-S orientation. The main storage sites consist of structural closures in Triassic strata of the Sherwood Sandstone Formation (SSF), overlain by alternations of mudstones and evaporites of the Triassic Mercia Mudstone Group (MMG). The closures occur predominantly at fault-bounded horsts, with adjacent grabens filled by thick sequences of the Triassic Mercia Mudstone Group (MMG). The fault framework was used to test, in 3D, the stress model published for the EISB and assess the fault reactivation risk associated with CO2 storage. Slip tendency values were predominantly below 0.6, suggesting the presence of stable structures in the EISB. Under the tested conditions, faults are capable of withstanding pressure increases between 3 MPa and 10 MPa before the onset of slip. The limited fault reactivation risk suggests CCS operations are suitable prospects for the EISB. This work demonstrates the additional value gained from integration of accurately constrained fault geometries in 3D stress models
Acute kidney injury in the era of the AKI E-Alert
Background and objectivesOur aimwas to use a national electronicAKI alert to define the incidence and outcome
of all episodes of community– and hospital–acquired adult AKI.
Design, setting, participants, & measurements A prospective national cohort study was undertaken in a
population of 3.06 million.Datawere collected betweenMarch of 2015 andAugust of 2015. All patients with adult
($18 years of age) AKI were identified to define the incidence and outcome of all episodes of community- and
hospital-acquired AKI in adults. Mortality and renal outcomes were assessed at 90 days.
Results There was a total of 31,601 alerts representing 17,689 incident episodes, giving an incidence of AKI of 577
per 100,000 population. Community-acquired AKI accounted for 49.3% of all incident episodes, and 42%
occurred in the context of preexisting CKD (Chronic Kidney Disease Epidemiology Collaboration eGFR); 90-day
mortality rate was 25.6%, and 23.7% of episodes progressed to a higher AKI stage than the stage associated with
the alert. AKI electronic alert stage and peak AKI stage were associated with mortality, and mortality was
significantly higher for hospital-acquired AKI compared with alerts generated in a community setting. Among
patients who survived to 90 days after the AKI electronic alert, those who were not hospitalized had a lower rate
of renal recovery and a greater likelihood of developing an eGFR,60 ml/min per 1.73m2 for the first time,which
may be indicative of development of de novo CKD.
Conclusions The reported incidence of AKI is far greater than the previously reported incidence in studies reliant
on clinical identification of adult AKI or hospital coding data. Although an electronic alert systemis Information
Technology driven and therefore, lacks intelligence and clinical context, these data can be used to identify deficiencies
in care, guide the development of appropriate intervention strategies, and provide a baseline against
which the effectiveness of these interventions may be measured
Efficacy of a New Angioplasty Catheter for Severely Narrowed Coronary Lesions
Conventional over the wire dilation catheters may be unsuccessful in crossing coronary lesions that are severely narrowed. Hence, a new, extremely low profile coronary angioplasty catheter specifically designed to dilate such lesions was investigated. The catheter features a 2.0, 2.5 or 3.0 mm (inflated diameter) balloon mounted on a guide wire. The deflated profile of the 2.0 mm balloon measures 0.020 ± 0.001 in. (0.51 ± 0.03 mm). The catheter can be used in conjunction with 7F angiographic or 8F guide catheters.The catheter was used in 61 patients, aged 43 to 86 years, with predominantly Canadian Cardiovascular Society class III-IV angina. Dilation was attempted in 77 lesions. Lesion length averaged 5.7 ± 3.1 mm (mean ± 1 SD), minimal diameter 0.51 ± 0.25 mm and internal vessel diameter 2.27 ± 0.43 mm. Sixty lesions (78%) were successfully dilated to <50% residual stenosis with this catheter alone; nine lesions were further dilated with a larger balloon catheter. The new catheter was unable to cross 13 lesions (17%); only 2 of these lesions were subsequently crossed with a conventional over the wire system. On the other hand, the catheter was used after failure of conventional dilating catheters in 21 lesions and was successful in 16. The new catheter was particularly valuable for distal lesions and those demonstrating 90 to 99 % diameter reduction. For all lesions crossed, stenosis decreased from 76 ± 11 to 29 ± 12% after 2.9 ± 2.7 inflations and peak inflation pressure of 8.0 ± 2.9 bar. Complications were rare; coronary occlusion occurred in two lesions (3%) and dissection in three lesions (4%). There were no instances of death or emergency coronary artery bypass surgery.Thus, this new angioplasty catheter was uniquely effective and safe in patients with severe coronary lesions. Importantly, success was often achieved after failure of conventional angioplasty catheters
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