bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adherence and health beliefs in a psychoeducative intervention in naïve HIV‐1‐infected men: the PROADH study
Authors: Fumaz C , Muñoz‐Moreno J , Ferrer M , Gonzalez‐Garcia M , Perez‐Alvarez N , Miranda C , Negredo E , Clotet B 
Published: November 2012

BackgroundHealth beliefs are an important factor in the maintenance of an adherent behaviour. However, specific interventions based on the modification of health beliefs to promote adherence have not been applied in naïve HIV‐infected subjects.MethodsProspective randomized 48‐week study to evaluate the efficacy of a psychoeducative intervention based on health beliefs to promote adherence in a sample of naïve HIV‐1‐infected men who started antiretroviral therapy. Participants were randomized to follow three intervention visits to promote adherence with the use of projective drawing techniques, Life‐steps and Motivational interview (Intervention Group; GI) or to continue with the routine care (Control Group; GC). Adherence was assessed through self‐report and drug plasma levels. Mann‐Whitney nonparametric test, w2 or Fisher exact test were used to compare variables.ResultsParticipants were 40 men with a median (IQ) age of 35.2 (30.2–44.8) years, CD4 cell count at the study entry of 316 (229–539) cells/mm3 and HIV‐RNA VL of 65.000 (22.500–250.000) copies. The infection route had been mainly MSM (90%). QD and BID ARV therapy was prescribed in 29 (72.5%) and 11 (27.5%) subjects. Seven patients (2 in GI; 5 in GC) were lost to follow‐up. At week 48, 100% of subjects in GI and 60% in GC had 100% adherence (p=0.01). In GC, 26% and 14% of subjects had ≥95% and <95% adherence, respectively. No differences were found in adherence regarding QD or BID therapy. All subjects except for 3 had VL <25 copies at week 48.ConclusionsHigh adherence was observed in the majority of this group of naïve HIV‐infected men who initiated their first antiretroviral therapy. However, all subjects following the intervention had 100% adherence after one year of follow‐up. A psychoeducative intervention based on the modification of health beliefs may be a useful strategy to promote adherence in naïve HIV‐infected patients.
Synthesis of F16 conjugated with 5‐fluorouracil and biophysical investigation of its interaction with bovine serum albumin by a spectroscopic and molecular modeling approach
Authors: Xiang Chen , Li Dong‐Wei , Qi Zu‐De , Jiang Feng‐Lei , Ge Yu‐Shu , Liu Yi 
Published: November 2012

ABSTRACT5‐Fluorouracil (5‐FU) has been widely used as a chemotherapy agent in the treatment of many types of solid tumors. Investigation of its antimetabolites led to the development of an entire class of fluorinated pyrimidines. However, the toxicity profile associated with 5‐FU is significant and includes diarrhea, mucositis, hand–foot syndrome and myelosuppression. In aiming at reducing of the side effects of 5‐FU, we have designed and synthesized delocalized lipophilic cations (DLCs) as a vehicle for the delivery of 5‐FU. DLCs accumulate selectively in the mitochondria of cancer cells because of the high mitochondrial transmembrane potential (ΔΨm). Many DLCs exhibited anti‐cancer efficacy and were explored as potential anti‐cancer drugs based on their selective accumulation in the mitochondria of cancer cells. F16, the DLC we used as a vehicle, is a small molecule that selectively inhibits tumor cell growth and dissipates mitochondrial membrane potential. The binding of the conjugate F16–5‐FU to bovine serum albumin (BSA) was investigated using spectroscopic and molecular modeling approaches. Fluorescence quenching constants were determined using the Stern–Volmer equation to provide a measure of the binding affinity between F16–5‐FU and BSA. The activation energy of the interaction between F16–5‐FU and BSA was calculated and the unusually high value was discussed in terms of the special structural block indicated by the molecular modeling approach. Molecular modeling showed that F16–5‐FU binds to human serum albumin in site II, which is consistent with the results of site‐competitive replacement experiments. It is suggested that hydrophobic and polar forces played important roles in the binding reaction, in accordance with the results of thermodynamic experiments. Copyright © 2012 John Wiley & Sons, Ltd.
Direct determination of sitagliptin in pharmaceutical formulations and its determination in urine after solid‐phase extraction by spectrofluorimetry
Authors: de Paula e Mancilha Taiza , de Paula Carlos Eduardo Rodrigues , Cassella Ricardo J. , Pacheco Wagner F. 
Published: November 2012

ABSTRACTThe fluorescence characteristics of sitagliptin phosphate were used to develop a methodology that allowed its determination in pharmaceutical formulations and urine samples; under the studied conditions, limits of determination and quantification of 0.25 and, respectively, 0.85 mg/L were achieved. Linear correlation between fluorescence analytical signal and sitagliptin concentration was achieved up to 10.0 mg/L. The method was considered selective for sitagliptin determination in pharmaceutical formulations because no interferences due to excipients present in considered matrix were observed (as demonstrated by recovery tests comparing analytical and addition curves). When the method was applied to urine samples, Interferences related to the matrix were observed, which made a solid‐phase extraction system necessary. The use of calibration was possible only by applying the standard addition method. Copyright © 2012 John Wiley & Sons, Ltd.
A soft‐switching high step‐up DC‐DC converter with a single magnetic component
Authors: Yang Jae‐Won , Do Hyun‐Lark 
Published: November 2012

SUMMARYA soft‐switching high step‐up DC‐DC converter with a single magnetic component is presented in this paper. The proposed converter can provide high voltage gain with a relatively low turn ratio of a transformer. Voltage doubler structure is selected for the output stage. Due to this structure, the voltage gain can be increased, and the voltage stresses of output diodes are clamped as the output voltage. Moreover, the output diode currents are controlled by a leakage inductance of a transformer, and the reverse‐recovery loss of the output diodes is significantly reduced. Two power switches in the proposed converter can operate with soft‐switching due to the reflected secondary current. The voltages across the power switches are confined to the clamping capacitor voltage. Steady‐state analysis, simulation, and experimental results for the proposed converter are presented to validate the feasibility and the performance of the proposed converter. Copyright © 2012 John Wiley & Sons, Ltd.
Multiple paternity in the freshwater snail, Potamopyrgus antipodarum
Authors: Soper Deanna M. , Delph Lynda F. , Lively Curt M. 
Published: November 2012

AbstractMating multiply may incur costs, such as exposure to predators and to sexually transmitted diseases. Nevertheless, it may be favored, in spite of these costs, as a way to increase the genetic diversity of offspring through fertilization by multiple males. Here, we tested for multiple paternity in a freshwater snail (Potamopyrgus antipodarum), which is host to several species of sterilizing trematode worms. Using microsatellites markers, we found multiple paternity in two different snail populations, with as many as seven males fertilizing a single female. In addition, high evenness of sire fertilization was found within individual broods. Multiple paternity can occur for a variety of reasons; however, given that these populations experience high risk of infection by a sterilizing trematode, one potential explanation may be that multiple paternity and high evenness of sire fertilizations increase the chances of the production of parasite‐resistant offspring.
Taylor's law and body size in exploited marine ecosystems
Authors: Cohen Joel E. , Plank Michael J. , Law Richard 
Published: November 2012

AbstractTaylor's law (TL), which states that variance in population density is related to mean density via a power law, and density‐mass allometry, which states that mean density is related to body mass via a power law, are two of the most widely observed patterns in ecology. Combining these two laws predicts that the variance in density is related to body mass via a power law (variance‐mass allometry). Marine size spectra are known to exhibit density‐mass allometry, but variance‐mass allometry has not been investigated. We show that variance and body mass in unexploited size spectrum models are related by a power law, and that this leads toTLwith an exponent slightly <2. These simulated relationships are disrupted less by balanced harvesting, in which fishing effort is spread across a wide range of body sizes, than by size‐at‐entry fishing, in which only fish above a certain size may legally be caught.
Effects of ozone on zinc and cadmium accumulation in wheat – dose–response functions and relationship with protein, grain yield, and harvest index
Authors: Pleijel Håkan 
Published: November 2012

AbstractResponse functions for the effect of ozone on cadmium (Cd) (toxic to humans) and zinc (Zn) (essential nutrient for plants and humans) in wheat grain were derived for the first time. Data from four open‐top chamber (OTC) experiments with field‐grown wheat, performed in southwest Sweden, were used. Ozone exposure was expressed as the phytotoxic ozone dose above a threshold of 6 nmol/m2 per sec (POD6), and AOT40. Grain Zn concentration was significantly enhanced by ozone, while Zn yield was not affected. The positive ozone effect on grain Zn concentration was almost twice as large as the corresponding effect on grain protein concentration, most likely as a result of nitrogen availability being more limiting than Zn availability. Cd concentration was unaffected by ozone, but Cd yield was significantly negatively affected. For the variables studied, correlation was stronger with POD6 than AOT40, but in several cases, for example, for Zn concentration and Cd yield, there was practically no difference in the performance between the two exposure indices. From the literature, it is obvious that ozone has important adverse effects on wheat yield and certain quality traits. As shown in this study, there are also examples of ozone leading to improved quality, for example, in terms of enhanced Zn concentration of wheat grain. While OTC enclosure did not affect Zn accumulation in wheat grain, Cd accumulation was significantly positively affected, most likely through transpiration being enhanced by the OTC environment, promoting Cd uptake and transport through the plant.
Extraction of Tryptophan enantiomers by aqueous two‐phase systems of ethanol and (NH4)2SO4
Authors: Chen Xiao‐qing , Dong Qiu‐li , Yu Jin‐gang , Jiao Fei‐peng 
Published: November 2012

AbstractBackgroundAs an important extraction technique, aqueous two‐phase extraction is especially applicable to bioseparation. This work has focused on using a novel kind of aqueous two‐phase system (ATPS), for the enantioseparation of tryptophan.ResultsOnly limited kinds of salts could form effective phases with ethanol. The salting‐out abilities of various salts and the final characteristics of ATPS were investigated. The results show that increase in the amount of phase‐forming components and decrease in pH from 6 to 2.5 are both beneficial for the enantioseparation of tryptophan; enantioselective extraction and partitioning behavior are mainly dependent on the pH of solution, the type of chiral extractant and its concentration. Furthermore, salt, ethanol and temperature also have some effects on the enantioseparation. Finally, the most reasonable extraction mechanism of the tryptophan enantiomers was suggested.ConclusionThe novel ATPS composed of ethanol/ammonium sulfate proposed in this studyhas good ability for the extraction of tryptophan enantiomers. © 2012 Society of Chemical Industry
Depletion of acidic phospholipids influences chromosomal replication in Escherichia coli
Authors: Fingland Nicholas , Flåtten Ingvild , Downey Christopher D. , Fossum‐Raunehaug Solveig , Skarstad Kirsten , Crooke Elliott 
Published: November 2012

AbstractIn Escherichia coli, coordinated activation and deactivation of DnaA allows for proper timing of the initiation of chromosomal synthesis at the origin of replication (oriC) and assures initiation occurs once per cell cycle. In vitro, acidic phospholipids reactivate DnaA, and in vivo depletion of acidic phospholipids, results in growth arrest. Growth can be restored by the expression of a mutant form of DnaA, DnaA(L366K), or by oriC‐independent DNA synthesis, suggesting acidic phospholipids are required for DnaA‐ and oriC‐dependent replication. We observe here that when acidic phospholipids were depleted, replication was inhibited with a concomitant reduction of chromosomal content and cell mass prior to growth arrest. This global shutdown of biosynthetic activity was independent of the stringent response. Restoration of acidic phospholipid synthesis resulted in a resumption of DNA replication prior to restored growth, indicating a possible cell‐cycle‐specific growth arrest had occurred with the earlier loss of acidic phospholipids. Flow cytometry, thymidine uptake, and quantitative polymerase chain reaction data suggest that a deficiency in acidic phospholipids prolonged the time required to replicate the chromosome. We also observed that regardless of the cellular content of acidic phospholipids, expression of mutant DnaA(L366K) altered the DNA content‐to‐cell mass ratio.
Fast direct fourier reconstruction of radial and PROPELLER MRI data using the chirp transform algorithm on graphics hardware
Authors: Feng Yanqiu , Song Yanli , Wang Cong , Xin Xuegang , Feng Qianjin , Chen Wufan 
Published: November 2012

PurposeTo develop and test a new algorithm for fast direct Fourier transform (DrFT) reconstruction of MR data on non‐Cartesian trajectories composed of lines with equally spaced points.Theory and MethodsThe DrFT, which is normally used as a reference in evaluating the accuracy of other reconstruction methods, can reconstruct images directly from non‐Cartesian MR data without interpolation. However, DrFT reconstruction involves substantially intensive computation, which makes the DrFT impractical for clinical routine applications. In this article, the Chirp transform algorithm was introduced to accelerate the DrFT reconstruction of radial and Periodically Rotated Overlapping ParallEL Lines with Enhanced Reconstruction (PROPELLER) MRI data located on the trajectories that are composed of lines with equally spaced points. The performance of the proposed Chirp transform algorithm‐DrFT algorithm was evaluated by using simulation and in vivo MRI data.ResultsAfter implementing the algorithm on a graphics processing unit, the proposed Chirp transform algorithm‐DrFT algorithm achieved an acceleration of approximately one order of magnitude, and the speed‐up factor was further increased to approximately three orders of magnitude compared with the traditional single‐thread DrFT reconstruction.ConclusionImplementation the Chirp transform algorithm‐DrFT algorithm on the graphics processing unit can efficiently calculate the DrFT reconstruction of the radial and PROPELLER MRI data. Magn Reson Med, 70:1087–1094, 2013. © 2012 Wiley Periodicals, Inc.
Sociodemographic factors influencing the use of injections in South Korean outpatient care
Authors: Lee Iyn‐Hyang , Park Sylvia , Lee Eui‐Kyung 
Published: November 2012

ABSTRACTPurposeThis study explored the relationship between sociodemographic factors and injection utilization in South Korea.MethodsWe conducted a retrospective cross‐sectional analysis using 2009 prescription claims for Korean National Health Insurance beneficiaries. We analyzed the utilization, costs, and proportion of injections in the insured market for oral‐injection dual‐dose‐form ingredients (DFIs). We included outpatients who were prescribed DFIs with no age limits. Descriptive analysis and multivariate logistic regression were performed to evaluate the predictive factors of injection use.ResultsInjections accounted for about 5% of outpatient utilization and costs of the study drugs. The odds of having injections were 1.3–1.6 times higher among those patients who are 70 years and older compared with those in the 20s, in smaller‐sized hospitals and clinics than that in larger, and among medical institutions in rural areas than those in the capital area. The odds of having injections were increased stepwise for the age groups of 30–69 years. Injections were more likely to be prescribed for systematic hormonal preparations and drugs for the musculoskeletal system.ConclusionsThe use of injections was higher among older groups, among smaller medical institutions, and among institutions in rural areas in Korean outpatient care. The difference between prescribing defined daily doses and prescribing rate for injections of the audit reports implies that Korean doctors prescribed injections often, but small doses for momentary effects in outpatient settings. Further studies are required to uncover the underlying causes of the high prevalence of injection use in older or rural populations and smaller institutions. Copyright © 2012 John Wiley & Sons, Ltd.
Short‐wave radiances: comparison between SEVIRI and the Unified Model
Authors: Thelen Jean‐Claude , Edwards John M. 
Published: November 2012

AbstractThe radiation scheme in the Met Office Unified Model (UM) is extended to allow the calculation of short‐wave radiances. Comparisons between short‐wave reflectances simulated with the global forecasting configuration of the UM and observations from SEVIRI (Spin Enhanced Visible and Infrared Imager) on board Meteosat 8 are presented. One of the main purposes for such a comparison is model validation, since it allows us to directly compare model and satellite reflectances, without having to make use of retrieval systems. Eliminating the retrieval algorithm has the advantage that we can be certain that any discrepancies between the modelled and the measured radiances are due to inaccuracies in the model, rather than differences in the assumptions made both in the model and the retrieval algorithm. In principle, this should allow us to detect weaknesses in the model parametrizations.In particular, we compare the four short‐wave channels of SEVIRI to the corresponding radiance simulations obtained from the UM over oceanic regions. Generally good agreement between the simulated and observed reflectances was obtained in the visible channels, but greater disagreement was found in the NIR 1.6 and IR 3.9 channels, hinting at deficiencies in the model's representation of particle size. Sensitivity studies are carried out to explore these sensitivities.
The Harmattan over West Africa: nocturnal structure and frontogenesis
Authors: Burton R. R. , Devine G. M. , Parker D. J. , Chazette P. , Dixon N. , Flamant C. , Haywood J. M. 
Published: November 2012

AbstractThis article presents observations and model simulations of the low‐level nocturnal structure of the atmosphere over West Africa. The measurements are taken from the dry‐season Special Observing Period (SOP‐0) of the African Monsoon Multidisciplinary Analysis (AMMA), at Niamey, Niger, on 23 and 24 January 2006. During this time, mesoscale structures in the atmospheric aerosol loadings were observed. The available observations indicate that these mesoscale features at Niamey are consistent with the passage of gravity currents or bores in the northerly Harmattan winds.Model simulations at resolutions down to 1 km indicate that the mesoscale structures are caused by nocturnal frontogenesis in the baroclinic zone to the south of the Sahara in the winter months. This frontogenesis is a continental‐scale phenomenon, which has significant implications for the uplift and transport of dust and biomass‐burning aerosols in the region. An accompanying frontogenetic feature appears further south in the model simulations, associated with the winter intertropical front. The frontogenesis is possibly linked with the development of structures showing characteristics of canonical mesoscale phenomena, including internal bores and gravity currents. Representation of these features in the UK Met Office Unified Model at different resolutions (from 12 km to 1 km) is discussed.
NWP model forecast skill optimization via closure parameter variations
Authors: Ollinaho Pirkka , Laine Marko , Solonen Antti , Haario Heikki , Järvinen Heikki 
Published: November 2012

AbstractWe apply a recently developed method, the Ensemble Prediction and Parameter Estimation System (EPPES), to demonstrate how numerical weather prediction (NWP) model closure parameters can be optimized. As proof of concept, we tune the medium‐range forecast skill of the ECMWF model HAMburg version (ECHAM5) atmospheric general circulation model using an ensemble prediction system (EPS) emulator. Initial state uncertainty is represented in the EPS emulator by applying the initial state perturbations generated at the European Centre for Medium‐range Weather Forecasts (ECMWF). Model uncertainty is represented in the emulator via parameter variations at the initial time. We vary four closure parameters related to parametrizations of subgrid‐scale physical processes of clouds and precipitation. With this set‐up, we generate ensembles of 10‐day global forecasts with the ECHAM5 model at T42L31 resolution twice a day over a period of three months. The cost function in the optimization is formulated in terms of standard forecast skill scores, verified against the ECMWF operational analyses. A summarizing conclusion of the experiments is that the EPPES method is able to find ECHAM5 model closure parameter values that correspond to smaller values of the cost function. The forecast skill score improvements verify positively in dependent and independent samples. The main reason is the reduced temperature bias in the tropical lower troposphere. Moreover, the optimization improved the top‐of‐atmosphere radiation flux climatology of the ECHAM5 model, as verified against the Clouds and the Earth's Radiant Energy System (CERES) radiation data over a 6‐year period, while the simulated tropical cloud cover was reduced, thereby increasing a negative bias as verified against the International Satellite Cloud Climatology Project (ISCCP) data.
Small‐scale structure of radiation fog: a large‐eddy simulation study
Authors: Bergot Thierry 
Published: November 2012

AbstractIn order to study the small‐scale structure of radition fog, large‐eddy simulations (LESs) of a fog case are analysed. The LESs were performed at very high resolution –2 m in the horizontal and 1 m in the vertical. Despite uncertainties in the measurements, particularly for advection, the main characteristics of the fog layer were well captured by the model. Radiation fog forms in statically stable stratification near the ground. During the formation phase, small stripes occur in the middle of the fog layer, associated with a significant burst in the turbulent kinetic energy (TKE). During the development phase, the dynamics of the fog layer change significantly. The maximum of the variance moves to the top of the fog layer where horizontal rolls appear clearly. These eddies have their centre near the mean top of the fog layer and have a depth corresponding to about one third of the fog layer height. This leads to a maximum of TKE at the top of fog, and to very strong scatter on the liquid water content. The energy is clearly produced at a length‐scale corresponding to the fog height. The turbulence is 3D homogeneous inside the fog layer, while it is better characterized by 2D turbulence near the top. During the dissipation phase, the radiative heating of the surface increases the convective structure of the fog. The dissipation of fog at ground level takes a long time (about 2 h), even if the soil conditions are homogeneous. The top of the stratus layer is homogeneous, while the spread of the base height reaches a value typical of the cloud thickness. Copyright © 2012 Royal Meteorological Society