99 research outputs found
Inter- and intragrain currents in bulk melt-grown YBaCuO rings
A simple contactless method suitable to discern between the intergrain
(circular) current, which flows in the thin superconducting ring, and the
intragrain current, which does not cross the weakest link, has been proposed.
At first, we show that the intergrain current may directly be estimated from
the magnetic flux density measured by the Hall sensor positioned
in the special points above/below the ring center. The experimental
and the numerical techniques to determine the value are discussed. Being
very promising for characterization of a current flowing across the joints in
welded YBaCuO rings (its dependencies on the temperature and the external
magnetic field as well as the time dissipation), the approach has been applied
to study corresponding properties of the intra- and intergrain currents flowing
across the -twisted grain boundaries which are frequent in bulk
melt-textured YBaCuO samples. We present experimental data related to the flux
penetration inside a bore of MT YBaCuO rings both in the non-magnetized, virgin
state and during the field reversal. The shielding properties and their
dependence on external magnetic fields are also studied. Besides, we consider
the flux creep effects and their influence on the current re-distribution
during a dwell.Comment: 13 pages, 16 figures (EPS), RevTeX4. In the revised version,
corrections to perturbing effects near the weak links are introduced, one
more figure is added. lin
Optimal management of barcelona water distribution network using non-linear model predictive control
© . This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/This paper presents a non-linear optimal control strategy for the operational management of water distribution networks (WDNs) including both flow and hydraulic head/pressure constraints. The optimal operation of WDNs should guarantee water supply with suitable pressures at all the demand nodes in the network. The challenge for non-linear model predictive control in this context is to compute control strategies for the pumps and valves in a WDN to supply the required demand while optimizing performance goals related to cost and safety. A two-layer scheme is used in order to produce set-points that can be directly sent to the actuators: on-off schedules for pumps and pressure set-points for pressures reducing valves. Finally, the results of applying the proposed control strategy to a portion of the Barcelona real WDN are provided.Peer ReviewedPostprint (author's final draft
Felodipine-metoprolol combination tablet: maintained health-related quality of life in the presence of substantial blood pressure reduction.
BACKGROUND: Most treated hypertensive patients do not achieve adequate blood pressure (BP) control. Initiating therapy with two drugs has been suggested when BP is >20/10 mm Hg above goal. To ensure patients' compliance, such treatment needs to be well tolerated and must not compromise health-related quality of life (HRQL). The primary objective of this study was to compare the effects on HRQL of initiating treatment with felodipine + metoprolol (F+M) fixed combination tablets, or enalapril (E), or placebo (P). METHODS: A total of 947 patients of both sexes with primary hypertension (diastolic BP 95 to 110 mm Hg), aged 20 to 70 years, participated in this randomized, double-blind, parallel group, 12-week, multicenter trial. Treatment was initiated with F+M 5 + 50 mg, or E 10 mg, or P. Doses were doubled after 4 or 8 weeks if diastolic BP was >90 mm Hg. The HRQL was measured at baseline and at the last visit using two validated questionnaires: the Psychological General Well-being Index (PGWB) and the Subjective Symptom Assessment Profile (SSA-P). Office BP was measured at trough, that is, 24 h after the previous dose. RESULTS: The HRQL was high at baseline and generally well maintained during the study. For example, the mean (SD) PGWB total score was 104 (16) at baseline and 105 (16) at 12 weeks in all three treatment groups. The BP reductions after F+M (18/14 mm Hg) and E (12/9 mm Hg) were significantly greater than after P (7/7 mm Hg), and the reduction after F+M was significantly greater than after E. CONCLUSIONS: The HRQL is maintained in the presence of substantial BP reduction during antihypertensive treatment with F+M fixed combination tablets
Dificultades para codificar, relacionar y categorizar problemas verbales algebraicos: dos estudios con estudiantes de secundaria y profesores en formaciĂłn
En resoluciĂłn de problemas verbales por transferencia, la activaciĂłn de problemas ya conocidos que sirvan de guĂa, depende de las analogĂas percibidas entre Ă©stos y el problema a resolver. Se desarrollan dos estudios relacionados para analizar en quĂ© caracterĂsticas se basan los estudiantes para codificar problemas y detectar sus analogĂas, en tareas de categorizaciĂłn (sorting). Se utilizaron tĂ©cnicas cuantitativas y cualitativas combinadas. Primero se analizĂł cĂłmo los estudiantes de secundaria son influidos por diferentes variables caracterĂsticas de problemas de ciencias. Una gran proporciĂłn de sujetos no fue capaz de percibir las analogĂas y diferencias adecuadas entre problemas. El segundo estudio tratĂł de avanzar una explicaciĂłn de estos resultados. El nivel acadĂ©mico y la familiaridad con las temĂĄticas fueron factores significativos, pero los futuros profesores participantes mostraron demasiadas dificultades, alertando sobre la conveniencia de revisar algunos supuestos instruccionales habituales
Perioperative tumor cell dissemination in patients with primary or metastatic colorectal cancer
The Cholecystectomy As A Day Case (CAAD) Score: A Validated Score of Preoperative Predictors of Successful Day-Case Cholecystectomy Using the CholeS Data Set
Background
Day-case surgery is associated with significant patient and cost benefits. However, only 43% of cholecystectomy patients are discharged home the same day. One hypothesis is day-case cholecystectomy rates, defined as patients discharged the same day as their operation, may be improved by better assessment of patients using standard preoperative variables.
Methods
Data were extracted from a prospectively collected data set of cholecystectomy patients from 166 UK and Irish hospitals (CholeS). Cholecystectomies performed as elective procedures were divided into main (75%) and validation (25%) data sets. Preoperative predictors were identified, and a risk score of failed day case was devised using multivariate logistic regression. Receiver operating curve analysis was used to validate the score in the validation data set.
Results
Of the 7426 elective cholecystectomies performed, 49% of these were discharged home the same day. Same-day discharge following cholecystectomy was less likely with older patients (OR 0.18, 95% CI 0.15â0.23), higher ASA scores (OR 0.19, 95% CI 0.15â0.23), complicated cholelithiasis (OR 0.38, 95% CI 0.31 to 0.48), male gender (OR 0.66, 95% CI 0.58â0.74), previous acute gallstone-related admissions (OR 0.54, 95% CI 0.48â0.60) and preoperative endoscopic intervention (OR 0.40, 95% CI 0.34â0.47). The CAAD score was developed using these variables. When applied to the validation subgroup, a CAAD score of â€5 was associated with 80.8% successful day-case cholecystectomy compared with 19.2% associated with a CAAD score >5 (pâ<â0.001).
Conclusions
The CAAD score which utilises data readily available from clinic letters and electronic sources can predict same-day discharges following cholecystectomy
Non-AIDS defining cancers in the D:A:D Study-time trends and predictors of survival : a cohort study
BACKGROUND:Non-AIDS defining cancers (NADC) are an important cause of morbidity and mortality in HIV-positive individuals. Using data from a large international cohort of HIV-positive individuals, we described the incidence of NADC from 2004-2010, and described subsequent mortality and predictors of these.METHODS:Individuals were followed from 1st January 2004/enrolment in study, until the earliest of a new NADC, 1st February 2010, death or six months after the patient's last visit. Incidence rates were estimated for each year of follow-up, overall and stratified by gender, age and mode of HIV acquisition. Cumulative risk of mortality following NADC diagnosis was summarised using Kaplan-Meier methods, with follow-up for these analyses from the date of NADC diagnosis until the patient's death, 1st February 2010 or 6 months after the patient's last visit. Factors associated with mortality following NADC diagnosis were identified using multivariable Cox proportional hazards regression.RESULTS:Over 176,775 person-years (PY), 880 (2.1%) patients developed a new NADC (incidence: 4.98/1000PY [95% confidence interval 4.65, 5.31]). Over a third of these patients (327, 37.2%) had died by 1st February 2010. Time trends for lung cancer, anal cancer and Hodgkin's lymphoma were broadly consistent. Kaplan-Meier cumulative mortality estimates at 1, 3 and 5 years after NADC diagnosis were 28.2% [95% CI 25.1-31.2], 42.0% [38.2-45.8] and 47.3% [42.4-52.2], respectively. Significant predictors of poorer survival after diagnosis of NADC were lung cancer (compared to other cancer types), male gender, non-white ethnicity, and smoking status. Later year of diagnosis and higher CD4 count at NADC diagnosis were associated with improved survival. The incidence of NADC remained stable over the period 2004-2010 in this large observational cohort.CONCLUSIONS:The prognosis after diagnosis of NADC, in particular lung cancer and disseminated cancer, is poor but has improved somewhat over time. Modifiable risk factors, such as smoking and low CD4 counts, were associated with mortality following a diagnosis of NADC
Study of the lineshape of the chi(c1) (3872) state
A study of the lineshape of the chi(c1) (3872) state is made using a data sample corresponding to an integrated luminosity of 3 fb(-1) collected in pp collisions at center-of-mass energies of 7 and 8 TeV with the LHCb detector. Candidate chi(c1)(3872) and psi(2S) mesons from b-hadron decays are selected in the J/psi pi(+)pi(-) decay mode. Describing the lineshape with a Breit-Wigner function, the mass splitting between the chi(c1 )(3872) and psi(2S) states, Delta m, and the width of the chi(c1 )(3872) state, Gamma(Bw), are determined to be (Delta m=185.598 +/- 0.067 +/- 0.068 Mev,)(Gamma BW=1.39 +/- 0.24 +/- 0.10 Mev,) where the first uncertainty is statistical and the second systematic. Using a Flatte-inspired model, the mode and full width at half maximum of the lineshape are determined to be (mode=3871.69+0.00+0.05 MeV.)(FWHM=0.22-0.04+0.13+0.07+0.11-0.06-0.13 MeV, ) An investigation of the analytic structure of the Flatte amplitude reveals a pole structure, which is compatible with a quasibound D-0(D) over bar*(0) state but a quasivirtual state is still allowed at the level of 2 standard deviations
Measurement of the CKM angle in and decays with
A measurement of -violating observables is performed using the decays
and , where the meson is
reconstructed in one of the self-conjugate three-body final states and (commonly denoted ). The decays are analysed in bins of the -decay phase space, leading
to a measurement that is independent of the modelling of the -decay
amplitude. The observables are interpreted in terms of the CKM angle .
Using a data sample corresponding to an integrated luminosity of
collected in proton-proton collisions at centre-of-mass
energies of , , and with the LHCb experiment,
is measured to be . The hadronic
parameters , , , and ,
which are the ratios and strong-phase differences of the suppressed and
favoured decays, are also reported
Novel Developments in Metabolic Disorders of Purine and Pyrimidine Metabolism and Therapeutic Applications of Their Analogs
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