bluuebunny/crossref_metadata_2025_split huggingface dataset:
Are the criteria currently used to rate the quality of clinical studies sufficient to warrant valid results?
Authors: Aust Norbert 
Published: November 2013

AbstractBackgroundCurrently, the quality of a clinical study is rated with respect to the risk of bias alone. Criteria for the internal validity of data assessment, and data processing, are not applied.MethodThis paper describes three major requirements for data validity as applied in, for instance, engineering: precision of data assessment; evaluation of significance; and definition of main outcome measure. The impact is illustrated using three high‐quality studies claiming to prove efficacy of homeopathic remedies.ResultThe three additional engineering criteria could be shown to have a substantial impact on the validity of the three studies discussed, which are considered as model studies, showing that in fact the evidence claimed therein is not warranted at all.ConclusionThis paper shows that, even for studies considered to be of high quality, data validity can be so problematic that the evidence claimed in the study is, in fact, useless. Much of the evidence base for homeopathy seems to suffer from that shortcoming, even if it is too early yet for generalisation. Whether evidence for other CAM therapies of even evidence‐based medicine suffers from the same problems is an open question as yet.
Looks Good, You’re Hired? Evidence from Extra-Parliamentary Activities of German Parliamentarians
Authors: Geys Benny 
Published: November 2013

AbstractPoliticians have been shown to benefit electorally from an attractive physical appearance. Employing data on 614 German MPs, this note explores whether it also affects their success/failure in the market for extra-parliamentary activities. An attractive physical appearance is found to mainly benefit female MPs, especially for private-sector jobs. This is particularly driven by MPs’ perceived likability. While MP’s perceived beauty is shown to have no direct effects for extra-parliamentary activities, our findings suggest important indirect effects.
A Leaky Aquifer below Champlain Sea Clay: Closed‐Form Solutions for Natural Seepage
Authors: Chapuis Robert P. , Saucier Antoine 
Published: November 2013

AbstractClosed‐form solutions are proposed for natural seepage in semiconfined (leaky) aquifers such as those existing below the massive Champlain Sea clay layers in the Saint‐Lawrence River Valley. The solutions are for an ideal horizontal leaky aquifer below an ideal aquitard that may have either a constant thickness and a constant hydraulic head at its surface, or a variable thickness and a variable hydraulic head at its surface. A few simplifying assumptions were needed to obtain the closed‐form solutions. These have been verified using a finite element method, which did not make any of the assumptions but gave an excellent agreement for hydraulic heads and groundwater velocities. For example, the difference between the two solutions was smaller than 1 mm for variations in the 5 to 8 m range for the hydraulic head in the semiconfined aquifer. Note that fitting the hydraulic head data of monitoring wells to the theoretical solutions gives only the ratio of the aquifer and aquitard hydraulic conductivities, a clear case of multiple solutions for an inverse problem. Consequently, field permeability tests in the aquitard and the aquifer, and pumping tests in the aquifer, are still needed to determine the hydraulic conductivity values.
Progress in Remediation of Groundwater at Petroleum Sites in California
Authors: McHugh Thomas E. , Kulkarni Poonam R. , Newell Charles J. , Connor John A. , Garg Sanjay 
Published: November 2013

AbstractQuantifying the overall progress in remediation of contaminated groundwater has been a significant challenge. We utilized the GeoTracker database to evaluate the progress in groundwater remediation from 2001 to 2011 at over 12,000 sites in California with contaminated groundwater. This paper presents an analysis of analytical results from over 2.1 million groundwater samples representing at least $100 million in laboratory analytical costs. Overall, the evaluation of monitoring data shows a large decrease in groundwater concentrations of gasoline constituents. For benzene, half of the sites showed a decrease in concentration of 85% or more. For methyl tert‐butyl ether (MTBE), this decrease was 96% and for TBE, 87%. At remediation sites in California, the median source attenuation rate was 0.18/year for benzene and 0.36/year for MTBE, corresponding to half‐lives of 3.9 and 1.9 years, respectively. Attenuation rates were positive (i.e., decreasing concentration) for benzene at 76% of sites and for MTBE at 85% of sites. An evaluation of sites with active remediation technologies suggests differences in technology effectiveness. The median attenuation rates for benzene and MTBE are higher at sites with soil vapor extraction or air sparging compared with sites without these technologies. In contrast, there was little difference in attenuation rates at sites with or without soil excavation, dual phase extraction, or in situ enhanced biodegradation. The evaluation of remediation technologies, however, did not evaluate whether specific systems were well designed or implemented and did not control for potential differences in other site factors, such as soil type.
Carbon isotope stratigraphy of Torinosu‐type limestone in the western Paleo‐Pacific and its implication to paleoceanography in the Late Jurassic and earliest Cretaceous
Authors: Kakizaki Yoshihiro , Kano Akihiro 
Published: November 2013

AbstractCarbon isotope stratigraphy of the Late Jurassic and earliest Cretaceous was revealed from Torinosu‐type limestone, which was deposited in a shallow‐marine setting in the western Paleo‐Pacific, in Japan. Two sections were examined; the Nakanosawa section of the late Kimmeridgian to early Tithonian age (Fukushima Prefecture, Northeast Japan), and the Furuichi section of the late Kimmeridgian to early Berriasian age (Ehime Prefecture, Southwest Japan). The age‐model was established using Sr isotope ratio and fossil occurrence. The limestone samples have a low Mn/Sr ratio (mostly <0.5) and lack a distinct correlation between δ13C and δ18O, indicating a low degree of diagenetic alteration. Our composite δ13C profile from the two limestone sections shows three stratigraphic correlation points that can be correlated with the profiles of relevant ages from the Alpine Tethyan region: a large‐amplitude fluctuation (the lower upper Kimmeridgian, ∼152 Ma), a positive anomaly (above the Kimmeridgian/Tithonian boundary, ∼150 Ma), and a negative anomaly (the upper lower Tithonian, ∼148 Ma). In addition, we found that δ13C values of the Torinosu‐type limestone are ∼1‰ lower than the Tethyan values in the late Kimmeridgian. This inter‐regional difference in δ13C values is likely to have resulted from a higher productivity and/or an organic burial in the Tethyan region. The difference gradually reduces and disappears in the late Tithonian, where the Tethyan and our δ13C records show similar stable values of 1.5–2.0‰. This isotopic homogenization is probably due to changes in the continental distribution and the global ocean circulation, which propagated the 13C‐depleted signature from the larger Paleo‐Pacific to the smaller Tethys Ocean during this time.
The effects of a catheter clamping protocol on bladder function in neurosurgical patients: A controlled trial
Authors: Liu Yi Si , Wei Shuang , Elliott Malcolm 
Published: November 2013

There is scant evidence‐based literature on the best strategies for short‐term urinary catheter removal. This clinical trial explored the effects of an early urinary catheter clamping protocol on bladder function in neurosurgical patients. Eligible patients were divided into observation and control groups. Those in the observation group had their catheter clamped postoperatively on return to the ward and unclamped at dedicated intervals. The control group received standard care; the catheter was on free drainage during the entire time in situ.The mean catheter indwelling time was 2.6 days. Compared with the control group, the observation group experienced shorter time to first postoperative urination, less residual urine volume and better subjective perception during their first postoperative urination. For patients undergoing neurosurgery and associated short‐term indwelling urinary catheterization, an early catheter clamping protocol is effective in facilitating bladder function, reducing the rate of dysuria and making patients feel more comfortable after catheter removal.
A Quiet Revolution in Corporate Governance: An Examination of Voluntary Best Practice Governance Policies
Authors: Baulkaran Vishaal 
Published: November 2013

AbstractThis paper investigates the effects of several voluntary best practice corporate governance principles on firm performance and firm risk. Using a sample of Standard & Poor's/Toronto Stock Exchange Composite Index firms from 2003–2010, I show that firms with individual director election and detailed disclosure of voting results in director elections have a higher firm value or performance. Firms with independent chairman, majority voting, and detailed disclosure of voting results in director elections have lower idiosyncratic risk. In addition, the results from the panel regression show that detailed disclosure of voting results in director election leads to lower systematic and total risk.
Compositional Dependence of CdSe Quantum Dot Formation on Silicate Host Glass Composition
Authors: Lee Yl Kwon , Choi Yong Gyu , Heo Jong , Chung Woon Jin 
Published: November 2013

Silicate glasses were synthesized with additional CdO and ZnSe of varying content. When CdO was added up to 3 mol% with the amount of ZnSe fixed at 1 mol%, absorption due to Se2− color centers significantly decreased and the color of glasses was bleached without any evidence of CdSe quantum dots (QDs). However, characteristic absorption due to CdSe QDs appeared without additional heat treatment when the ZnSe content exceeded 1.5 mol%, whereas the CdO content was fixed at 1 mol%. Raman spectra and transmission electron microscopy verified the formation of CdSe QDs. The role of CdO and ZnSe in CdSe QD formation has been discussed in relation to their structural contribution within silicate glasses.
Ion‐Beam Etching on Nanostructured La2Ti2O7 Piezoelectric Thin Films
Authors: Ferri Anthony , Saitzek Sébastien , Shao Zhenmian , Declercq Gaëtan , Costecalde Jean , Rémiens Denis , Deresmes Dominique , Troadec David , Desfeux Rachel 
Published: November 2013

The impact of generated Ga+ ion beams on the functional properties of crystallized lanthanum dititanate oxide (La2Ti2O7) ferroelectric thin films has been investigated at the nanometer scale by means of the scanning probe microscopy. Both the surface and the electrical response are shown to undergo sensitive modifications for areas exposed to ion irradiation. These are revealed through dynamic force mode, Kelvin force, and piezoresponse force (PFM) microscopies. Despite the nanometer film‐dimensions, local piezoactivity is still detected, thus confirming the high resistance of the material to ion‐beam exposures. In addition, crystallized La2Ti2O7 film, with a Pt electrode on top, is successfully patterned by focused ion beam (FIB) process. This allows the achieving of localized islands with lateral sizes ranging from 500 to 300 nm. Nanoscale electromechanical response is measured inside these nanostructures with the help of the PFM technique. In this case, the local piezosignal exhibits a level similar to the one obtained for the unetched film. The measures evidence no obvious sidewall effect in spite of not using the usual postannealing treatment that leads to functional properties recovery. This study demonstrates that the use of La2Ti2O7 materials combined with the FIB technique constitute a suitable and promising test‐bench to pattern low‐dimensional nanostructures. These investigations bear significant implications in view of the development of lead‐free piezoelectric thin films for nanoelectromechanical systems applications.
Invar Like Behavior of the Cr2AlC MAX Phase at Low Temperature
Authors: Jaouen Michel , Chartier Patrick , Cabioc'h Thierry , Mauchamp Vincent , André Gilles , Viret Michel 
Published: November 2013

The structure of Cr2AlC has been studied using neutron scattering experiments performed in a temperature range running from room temperature down to 1.8 K. It is shown that the unit cell volume does not vary significantly below 80 K. This anomalous behavior, correlated with the existence of a weak ferromagnetic ordering revealed from superconducting quantum interference device experiments, is similar to that characteristic of Invar alloys. Just above the Curie temperature TC ~ 73 ± 5 K, the Cr2AlC undergoes significant distortions of the octahedron and triangular prisms units. Above 100 K, Cr2AlC follows an usual thermal expansion.
Optimization of Isoamyl Acetate Production in a Solvent‐Free System
Authors: Azudin N. Yusoff , Mashitah M.D. , Abd Shukor S.R. 
Published: November 2013

AbstractEnzymatic esterification of isoamyl acetate using Candida antarctica immobilized lipase was studied and optimized using response surface methodology (RSM) by Design of Experiment software. Isoamyl acetate is a colorless organic compound which is used by food industry as additives for its banana flavor. The production of isoamyl acetate is costly, hence, RSM giving advantages by minimizing the number of experiments for studying parameter effect. The model developed by RSM also simplified the relationship that can be used for practical engineering purposes. The parameters investigated in this study are mass of enzyme (1–14 wt %), reaction temperature (30–50C) and reaction time (2–6 h). As reaction temperature increased at any given mass of enzyme, a yield of ester increased up to optimum temperature 40C and thereafter decreased. The model obtained by RSM indicated the optimum conditions for maximum esterification (100% yields) at 34.8C with 1.04 g mass of enzyme after 0.5 h reaction time, which is in good agreement with the experimental value (104%).Practical ApplicationsIsoamyl acetate is a compound that has a strong fruity aroma similar to banana and pear. It is commonly used as food flavor in the food industry. Apart from that, it is also popular as a solvent for varnishes, paints and nitrocellulose lacquers. The compound is also used in rayon, dyes, artificial pearls, film manufacturing and extraction of penicillin.
Metabolic syndrome association with fibrosis development in chronic hepatitis B virus inactive carriers
Authors: Mena Álvaro , Pedreira José D , Castro Ángeles , López Soledad , Vázquez Pilar , Poveda Eva 
Published: November 2013

AbstractBackground and AimThere are few data of fibrosis development in chronic hepatitis B (CHB) patients classified as inactive carriers. The aim of this study is to determinate the prevalence of significant fibrosis and probable cirrhosis measured by FibroScan in real inactive CHB carriers and investigate the relationship with virological, epidemiological, and metabolic factors.MethodsCross‐sectional cohort study including CHB inactive carriers. Liver stiffness measurement was performed with transient elastography (FibroScan). Significant fibrosis (≥ F2) was defined as stiffness > 7.5 kPa, and probable cirrhosis as > 11.8 kPa. Factors associated with significant fibrosis were explored with univariate and multivariate adjusted logistic regression analyses.ResultsNinety‐six CHB inactive carriers were analyzed. Of them, 24 (25%) had significant fibrosis and 7 (7%) probable cirrhosis; mean stiffness was 6.2 ± 2.3 kPa.Of them, 24% had metabolic syndrome, with higher FibroScan value than those without (8.4 kPa vs 5.5 kPa, P < 0.001).Factors associated with significant fibrosis were (odds ratio, 95% confidence interval, P value): central obesity (7.1, 1.8–27.9, 0.005), elevated fasting glucose (4.3, 1.3–27.9, 0.036), reduced high‐density lipoprotein cholesterol (5.2, 1.2–23.6, 0.032) and elevated triglycerides (6.2, 1.4–28.3, 0.019). Factors as age, sex, transaminases, hepatitis B virus DNA or genotype were not related with liver fibrosis.The presence of metabolic syndrome has a 69% of positive predictive value and 89% of negative predictive value for significant fibrosis.ConclusionDifferent components of metabolic syndrome are associated with fibrosis development in CHB inactive carriers. In the absence of metabolic syndrome, significant fibrosis is uncommon in this population.
Comparing the efficacy and clinical outcome of telbivudine and entecavir naïve patients with hepatitis B virus‐related compensated cirrhosis
Authors: Tsai Ming‐Chao , Yu Hsien‐Chung , Hung Chao‐Hung , Lee Chuan‐Mo , Chiu King‐Wah , Lin Ming‐Tzung , Tseng Po‐Lin , Chang Kuo‐Chin , Yen Yi‐Hao , Chen Chien‐Hung , Hu Tsung‐Hui 
Published: November 2013

AbstractBackground and AimThere is limited data on the efficacy and outcome of telbivudine (LdT) therapy in patients with chronic hepatitis B and compensated cirrhosis. We evaluated LdT as first‐line therapy in these patients and compared with those treated with entecavir (ETV).MethodsWe consecutively enrolled 88 chronic hepatitis B patients with compensated cirrhosis primarily treated with LdT at least for 2 years or less than 2 years but developed resistance, and evaluated the efficacy and clinical outcomes. Meanwhile, we matched a control group who treated with ETV for comparison.ResultsIn LdT group, alanine aminotransferase normalization (65.8%), hepatitis B e antigen seroconversion (39.8%), hepatitis B virus (HBV) DNA undetectablility (71.6%), and virologic resistance (23.9%) were noted after 2 years treatment. Compared with ETV group, there were significant difference in HBV DNA undetectablility (P < 0.001) and virologic resistance (P < 0.001). In addition, the decline of serum hepatitis B surface antigen levels, hepatocellular carcinoma development, mortality, disease progression, and the change of renal function were similar. Cox regression analysis showed that pretreatment low albumin level and high model for end‐stage liver disease scores were risk factors for disease progression.ConclusionsThese results indicated that although LdT and ETV are similar in clinical outcomes for patients with HBV‐related compensated cirrhosis, LdT still had lower HBV undetectablility and higher resistant rate after 2 years treatment, which was a challenge for being as first‐line therapy in these patients who need lifelong therapy.
A Fractal Approach to Microstructural Changes during the Storage of Yoghurts Prepared with Starter Cultures Producing Exopolysaccharides
Authors: Smoczyński Michał , Baranowska Maria 
Published: November 2013

AbstractChanges were evaluated in the properties of the microstructure during storage of yoghurts obtained with three commercial bacterial starter cultures differing in their ability to produce exopolysaccharides (EPS). The syneresis and rheological parameters were investigated during 28 days of storage. Changes in yoghurt microstructure were also monitored by image analysis processing to calculate the fractal dimension. Yoghurts prepared with EPS‐producing lactic acid bacteria showed higher values of viscosity and hysteresis loop area and lower amounts of whey separation. The calculated fractal dimension indicated changes in the porosity of yoghurt gels during storage. Different relationships between fractal dimension and syneresis and hysteresis loop area were observed for EPS and non‐EPS yoghurts, which may suggest alternative mechanisms of their microstructural behavior and confirm the important role of EPS for yoghurt properties. Fractal geometry provides a powerful method to investigate the properties of irregular structures which are otherwise undetectable.Practical ApplicationsYoghurt has a porous structure built of a protein network. Many physical properties of yoghurt depend on this microstructure. EPS produced by various lactic acid bacteria affect yoghurt microstructure and texture properties to a large extent. During microscopic observation, characterization of such objects is often limited to verbal description and many subtle differences between similar structures escape detection. In this case, fractal geometry can be used for precise mathematical description of such microstructure. The presented method of image analysis and calculation of the fractal dimension of pores in yoghurt microstructure can be a useful tool for yoghurt comparison and even classification of lactic acid bacteria properties.
Plasma Renin Activity and Aldosterone Concentrations in Hypertensive Cats with and without Azotemia and in Response to Treatment with Amlodipine Besylate
Authors: Jepson R.E. , Syme H.M. , Elliott J. 
Published: November 2013

BackgroundRole of renin‐angiotensin aldosterone system (RAAS) in feline systemic hypertension is poorly understood.ObjectivesExamine plasma renin activity (PRA) and plasma aldosterone concentrations (PAC) in normotensive and hypertensive cats with variable renal function and in response to antihypertensive therapy.AnimalsOne hundred and ninety‐six cats >9 years from first opinion practice.MethodsPRA,PAC, and aldosterone‐to‐renin ratio (ARR) were evaluated in cats recruited prospectively and grouped according to systolic blood pressure (SBP) and renal function (nonazotemic normotensive [Non‐Azo‐NT], nonazotemic hypertensive [Non‐Azo‐HT], azotemic normotensive [Azo‐NT], azotemic hypertensive [Azo‐HT]). Changes inPRAandPACwere evaluated with antihypertensive therapy (amlodipine besylate).ResultsPlasma renin activity (ng/mL/h;P = .0013),PAC(pg/mL;P < .001), andARR(P = 0.0062) differed significantly among groups.PRA(ng/mL/h) was significantly lower in hypertensive (Non‐Azo‐HT; n = 25, median 0.22 [25th percentile 0.09, 75th percentile 0.39], Azo‐HT; n = 44, 0.33 [0.15, 0.48]) compared with Non‐Azo‐NTcats (n = 57, 0.52 [0.28, 1.02]). Azo‐HTcats had significantly higherPAC(n = 22, 149.8 [103.1, 228.7]) than normotensive cats (Non‐Azo‐NT; n = 26, 45.4 [19.6, 65.0], Azo‐NT; n = 18, 84.1 [38.6, 137.8]).ARRwas significantly higher in Azo‐HT(n = 20, 503.8 [298.8, 1511]) than Azo‐NTcats (n = 16, 97.8 [77.0, 496.4]). Significant increase inPRAwas documented with antihypertensive therapy (pretreatment [n = 20] 0.32 [0.15–0.46], posttreatment 0.54 [0.28, 1.51]), butPACdid not change.Conclusions and Clinical ImportanceHypertensive cats demonstrate significantly increasedPACwith decreasedPRA.PRAsignificantly increases with antihypertensive therapy. Additional work is required to determine the role of plasma aldosterone concentration in the pathogenesis of hypertension and whether this relates to autonomous production or activation ofRAASwithout demonstrable increase inPRA.
On the Preprocessing of Atrial Electrograms in Atrial Fibrillation: Understanding Botteron's Approach
Authors: CASTELLS FRANCISCO , CERVIGÓN RAQUEL , MILLET JOSÉ 
Published: November 2013

BackgroundThe dominant atrial frequency is a key parameter for the analysis of atrial fibrillation (AF) from intracardiac recordings. The preprocessing approach employed by Botteron et al. in an early work is able to retrieve this frequency. The preprocessing steps are: (1) 40–250‐Hz band‐pass filtering, (2) rectification, and (3) 20 Hz low‐pass filtering.Methods and resultsThe theoretical aspects of this process are addressed. Moreover, its time‐domain and frequency‐domain properties are evaluated using both simulations and real electrogram (EGM) recordings. The fundamental frequency is emphasized, due to the rectification step. As the interval between consecutive activations becomes more irregular, fundamental frequency detection becomes less robust. In the case of fractionated EGM, this approach fails. In time‐domain, the waveform of the atrial beats are dramatically modified, hence hindering any further analysis on the morphology of the activations.ConclusionsBotteron preprocessing succeeds in estimating the dominant atrial rate in most EGMs during AF. However, this approach presents some limitations and improved methods are required.