bluuebunny/crossref_metadata_2025_split huggingface dataset:
The QT Interval as a Noninvasive Marker of Atrial Refractoriness
Authors: NGUYEN KAYLIN T. , GLADSTONE RACHEL A. , DUKES JONATHAN W. , NAZER BABAK , VITTINGHOFF ERIC , BADHWAR NITISH , VEDANTHAM VASANTH , GERSTENFELD EDWARD P. , LEE BYRON K. , LEE RANDALL J. , TSENG ZIAN H. , OLGIN JEFFREY E. , SCHEINMAN MELVIN M. , MARCUS GREGORY M. 
Published: October 2016

BackgroundAtrial refractoriness may be an important determinant of atrial fibrillation (AF) risk, but its measurement is not clinically accessible. Because the QT interval predicts incident AF and the atrium and ventricle share repolarizing ion currents, we investigated the association between an individual's QT interval and atrial effective refractory period (AERP).MethodsIn paroxysmal AF patients presenting for catheter ablation, the QT interval was measured from the surface 12‐lead electrocardiogram. The AERP was defined as the longest S1–S2 coupling interval without atrial capture using a 600‐ms drive cycle length.ResultsIn 28 patients, there was a positive correlation between QTc and mean AERP. After multivariate adjustment, a 1‐ms increase in QTc predicted a 0.70‐ms increase in AERP.ConclusionsThe QTc interval reflects the AERP, suggesting that the QTc interval may be used as a marker of atrial refractoriness relevant to assessing AF risk and mechanism‐specific therapeutic strategies.
High Left Ventricular Lead Sensing Delay Predicts QRS Narrowing and Good Response to Cardiac Resynchronization Therapy
Authors: KAYPAKLI ONUR , KOÇ MEVLÜT , GÖZÜBÜYÜK GÖKHAN , ŞAHİN DURMUŞ YILDIRAY 
Published: October 2016

BackgroundCardiac resynchronization therapy (CRT) was shown to improve heart failure (HF) prognosis. But many patients do not benefit from CRT. Optimization of left ventricular (LV) lead position to the latest activated LV area is important to increase CRT response. We aimed to detect the relationship between LV lead sensing delay and echocardiographic and electrocardiographic response to CRT treatment.MethodsWe prospectively included 156 consecutive patients with HF diagnosis, QRS ≥ 120 ms, left bundle branch block, New York Heart Association II–IV, LV ejection fraction (LVEF) < 35%, and scheduled for CRT (100 male, 56 female; mean age 65.8 ± 10.06 years). Echocardiographic CRT response was defined as ≥15% reduction in LV end‐systolic volume (LVESV). LV lead sensing delay was calculated as the time interval from the onset of surface QRS wave to the onset of depolarization wave recorded from the LV lead by using the LV pacing lead as a bipolar electrode.ResultsLVESV reduction was associated with baseline QRS width (r = 0.292, P = 001), QRS narrowing (r = 0.332, P < 001), and LV lead sensing delay (r = 0.454, P < 001) in bivariate analysis. In logistic regression analysis, LV lead sensing delay was found to be the only independent parameter for predicting significant LVESV reduction (β = 0.423, P < 0.001). LV lead sensing delay was also found to be significantly associated with LVEF increase (r = 0.320, P < 0.001) and QRS narrowing (r = 0.345, P < 0.001).ConclusionLV lead sensing delay is the only independent predictor for significant reduction in LVESV and was found to be significantly associated with LVEF increase and QRS narrowing after CRT treatment. We suggest that LV lead sensing delay may be used as a marker to predict the favorable response to CRT.
High hydrogen peroxide production and antioxidative enzymes expression in the Chlamydomonas reinhardtii cia3 mutant with an increased tolerance to cadmium and anthracene
Authors: Aksmann Anna , Pokora Wojciech , Baścik‐Remisiewicz Agnieszka , Dettlaff‐Pokora Agnieszka , Tukaj Zbigniew 
Published: October 2016

SUMMARYChlamydomonas reinhardtii cia3 mutant is deficient in activity of CAH3, a carbonic anhydrase isoform necessary for proper functioning of photosystem II (PS II). We used cia3 to verify the hypothesis that despite high concentration of external CO2, deficiency in CAH3 activity results in slight disorder of photosynthesis, which leads to mild but permanent overproduction of reactive oxygen species (ROS). As a consequence, cia3 should possess high ability to rebalance ROS homeostasis to overcome the oxidative stress induced by environmental factors, including chemical contaminations. We have found that in control conditions cia3 had a larger fraction of active PS II reaction centers but their efficiency was lower as compared with the wild type (WT), while H2O2 production by cia3 was significantly higher than in WT. In regard to ROS‐scavenging enzymes, the transcript level for superoxide dismutase (SOD) isoforms and the isoenzymes activity in cia3 were higher than in WT. There were no significant differences in the transcript level of ascorbate peroxidase (APX) and catalase (CAT) genes in both strains, and slightly elevated activity of the enzymes was observed in the cia3‐cells. Comparing the sensitivity of WT and cia3 to chemically‐induced stress we have found that the growth, photosynthesis and H2O2 production in WT were more strongly affected by cadmium and anthracene as compared with cia3. SODs expression and activity in the treated WT were higher than those in cia3, but APX and CAT activities were similar in both strains. Our results indicate that the CAH3‐deficiency is associated with markedly elevated H2O2 production and with a relatively higher initial transcript level and the activity of ROS‐scavenging enzymes. In consequence, cia3 revealed a higher tolerance to cadmium and anthracene compared with WT.
Using ERPs to investigate valence processing in the affect misattribution procedure
Authors: Von Gunten Curtis D. , Bartholow Bruce D. , Scherer Laura D. 
Published: October 2016

AbstractThe construct validity of the affect misattribution procedure (AMP) has been challenged by theories proposing that the task does not actually measure affect misattribution. The current study tested the validity of the AMP as a measure of affect misattribution by examining three components of the ERP known to be associated with the allocation of motivated attention. Results revealed that ERP amplitudes varied in response to affectively ambiguous targets as a function of the valence of preceding primes. Furthermore, differences in ERP responses to the targets were largely similar to differences in ERPs elicited by the primes. The existence of valence differentiation in both the prime‐locked and the target‐locked ERPs, along with the similarity in this differentiation, provides evidence that the affective content of the primes is psychologically registered, and that this content influences the processing of the subsequent, evaluatively ambiguous targets, both of which are required if the priming effects found in the AMP are the result of affect misattribution. However, the behavioral priming effect was uncorrelated with ERP amplitudes, leaving some question as to the locus of this effect in the information‐processing system. Findings are discussed in light of the strengths and weaknesses of using ERPs to understand the priming effects in the AMP.
Indirect Realism with a Human Face
Authors: DePoe John M. 
Published: October 2016

AbstractEpistemic Indirect Realism (EIR) is the position that justification for contingent propositions about the extra‐mental world requires an inference based on a subjective, experiential mental state. One objection against EIR is that it runs contrary to common sense and practice; in essence, ordinary people do not form beliefs about things in the external world on the basis of experiential mental states. This objection implies EIR is contrary to ordinary experience, impractical, and leads to scepticism. In this paper, I will defend EIR against this objection by distinguishing EIR based on conceptual awareness and non‐conceptual awareness. In particular, I will argue that direct acquaintance provides sufficient (non‐conceptual) awareness that can explain how ordinary folks are capable of forming justified beliefs about the external world in a way consistent with EIR. Overall, I present a framework for showing that EIR can satisfy ordinary epistemic practices without betraying human nature or over‐intellectualizing the required epistemic standards for possessing a justified belief.
Rapid dipstick detection of Vibrio cholerae in household stored and municipal water in Dhaka, Bangladesh: CHoBI7 trial
Authors: Rashid Mahamud‐ur , Rahman Zillur , Burrowes Vanessa , Perin Jamie , Mustafiz Munshi , Monira Shirajum , Saif‐Ur‐Rahman K. M. , Bhuyian Sazzadul Islam , Mahmud Md. Toslim , Sack R. Bradley , Sack David , Alam Munirul , George Christine Marie 
Published: October 2016

AbstractObjectiveIn urban Dhaka, Bangladesh, 30% of source water samples collected from the households of patients with cholera had detectable Vibrio cholerae. These findings indicate an urgent need for a public health intervention for this population. The Crystal VC® dipstick test is a rapid method for detecting V. cholerae in stool and water. However, to date no study has investigated the use of the rapid dipstick test for household surveillance of stored drinking water.MethodsThe efficacy of the Crystal VC® dipstick test for detecting V. cholerae in the Dhaka city municipal water supply and stored household drinking water sources after enrichment for 18 h in alkaline peptone water (APW) was compared to bacterial culture as the gold standard.ResultsA total of 1648 water samples (824 stored household drinking water samples and 824 municipal water supply samples) were collected from households of patients with cholera. The overall specificity and sensitivity of the dipstick test compared to bacterial culture was 99.6% (95% confidence interval (CI): 99.2%, 99.9%) and 65.6% (95% CI: 55.2%, 75%), respectively. The specificities for stored household drinking water and Dhaka city municipal supply water compared to bacterial culture were 99.8% (95% CI: 99.1%, 100%) and 99.5% (95% CI: 98.6%, 99.9%), respectively (P = 0.138), and the sensitivities were 66.7% (95% CI: 43.0%, 85.4%) and 65.3% (95% CI: 53.5%, 76.0%), respectively (P = 0.891).ConclusionThe Crystal VC® dipstick is a promising screening tool for cholera outbreak surveillance in resource‐limited settings where elimination of false‐positive results is critical. The lower than expected sensitivity should be further investigated in future studies.
Human papillomavirus (HPV) awareness and vaccine receptivity among Senegalese adolescents
Authors: Massey Philip M. , Boansi Ruth K. , Gipson Jessica D. , Adams Rachel M. , Riess Helene , Dieng Thierno , Prelip Michael L. , Glik Deborah C. 
Published: October 2016

AbstractObjectiveTo examine HPV vaccine awareness and receptivity among adolescents and young adults in Senegal.MethodsParticipants from six high schools and five community centres across five regions of Senegal (n = 2286) completed a self‐administered questionnaire in October and November 2014. The study assessed HPV awareness and receptivity towards receiving the HPV vaccine. Multivariable logistic regression explored statistically significant relationships between the predictor variables and both outcomes.ResultsTwenty‐seven percent had heard of HPV. Among those who had heard of HPV (n = 616), only 28% indicated willingness to vaccinate. Multivariable analysis showed that respondents from rural areas had 63% higher odds (95% CI: 1.24, 2.12) of having heard of HPV than those in urban areas. Respondents with fathers who had completed higher education had 41% higher odds (95% CI: 1.04, 1.92) of being aware of HPV (P < 0.05); however, every level of father's education (as compared to no education at all) was negatively associated with willingness to vaccinate. Respondents who had previously spoken to a healthcare professional about the HPV vaccine had 80% higher odds (95% CI: 1.16, 2.81) of willingness to vaccinate than those who did not speak to a provider about the vaccine.ConclusionsHealthcare providers and parents are important stakeholders in disseminating HPV vaccine information. Given the overall low levels of awareness, there is a great opportunity for public health communication efforts to craft health messaging and information in a way to maximise receptivity, outlining benefits and providing information on the minimal risks associated with the vaccine.
Stability of osmolality in previously frozen canine serum and urine samples
Authors: Reinhart Jennifer M. , White Brad J. , Pohlman Lisa M. , Schermerhorn Thomas 
Published: October 2016

BackgroundThe measurement of osmolality is of interest in several clinical conditions and has been investigated in multiple veterinary studies. However, the stability of osmolality over time in frozen canine serum and urine has not been established.ObjectivesThe purpose of this study was to determine the stability of osmolality in canine serum and urine stored frozen at −20°C and −80°C up to 90 days, and to assess the effect of storage temperature on osmolality measurement.MethodsSerum and urine samples collected from 5 healthy Greyhound dogs were aliquoted and stored at −20°C and −80°C until measurement. Osmolality, assessed by freezing‐point depression, was measured at 0, 7, 14, 30, and 90 days of storage.ResultsFor both serum and urine, osmolality at day 7 was not statistically different from day 0, but osmolality at days 14, 30, and 90 was significantly lower than at day 0. There was no significant effect of storage temperature on serum osmolality. However, the osmolality of urine samples stored at −20°C was slightly, but significantly lower than the osmolality of those stored at −80°C.ConclusionsOsmolality measurement in the serum and urine of healthy dogs appears to be stable for at least 7 days in frozen samples. The small changes observed after day 7 are unlikely to be relevant for individual patients, but could have implications in research study protocols.
Assessment of Residual Stress and Suitability for Subsea Service of a Welded Superduplex Stainless Steel Flange Joint
Authors: Dodge M. , Smith S. D. , London T. , Sotoudeh K. , Morana R. , Kabra S. 
Published: October 2016

Ferritic-austenitic (duplex) stainless steel components are used for oil and gas production duties due to their high strength and corrosion resistance. The material is routinely used for short flowlines, as well as for welded hubs and flanges. Cathodic protection (CP) is employed, via sacrificial aluminium based anodes, which protects ferritic steel parts from seawater corrosion. Whilst CP has proven successful in preventing corrosion, failures have occurred due to the ingress of electrolytically evolved hydrogen. Duplex stainless steel joints become susceptible to environmental cracking under a combination of high stress, hydrogen content, and susceptible microstructures; critical combinations of which may result in hydrogen induced stress cracking (HISC).
Successful operation of duplex equipment, in avoidance of HISC, necessitates a good understanding of the total in-service stresses (including from loading applied in service and from residual stresses from manufacture, fabrication, installation and commissioning). One of the key components of understanding the in-service stress at welds is knowledge of the residual stress distribution, following welding. The focus of this paper is to provide an overview of the typical residual stress levels in a welded superduplex stainless steel (SDSS) subsea joint, using neutron diffraction and finite element modelling. The results are presented in the context of current recommended practice, for example DNV RP-F112.
Validation: What, Why and How
Authors: Eça Luís , Vaz Guilherme , Koop Arjen , Pereira Filipe , Abreu Hugo 
Published: October 2016

Offshore and Naval engineering have relied on physical models, i.e. experimental fluid dynamics (EFD), for several decades. Although the role of experiments in engineering is still unquestionable, some of the limitations of physical models, as for example domain size (blockage and scale effects), can be addressed using mathematical models, i.e. computational fluid dynamics (CFD). However, to gain confidence in the use of CFD it is fundamental to determine the modelling accuracy, i.e. to determine the difference between the “physical reality” and the selected mathematical model. The quantification of the modelling error is the goal of Validation. It must be emphasized that Validation applies to the mathematical model (and not the code) and is performed for selected flow quantities (the so-called quantities of interest).
Ideally, Validation would be performed comparing an exact measurement of the “physical reality” with the exact solution of the selected mathematical model. However, exact measurements do not exist and mathematical models for turbulent flows do not have analytical solutions. Therefore, procedures must be developed to take into account experimental and numerical uncertainties. Furthermore, the exact values of the flow parameters as for example Reynolds number, fluid viscosity or inlet turbulence quantities are often unknown, which leads to the so-called parameter uncertainty that also has to be dealt within the assessment of the modelling error.
The main goal of this paper is to demonstrate that the very popular designation of “code X is validated” is meaningless without saying what is the mathematical model embedded in the code, what are the quantities of interest for the specific application and what is the Validation uncertainty imposed by the experimental, numerical and parameter uncertainties. Furthermore, we also illustrate that Validation is not a pass or fail exercise. A modelling error of 10% may be acceptable for a given application, whereas 1% may not be enough for a different one.
To this end, we present the application of the ASME V&V 20 Validation procedure for local set points and the metric for multiple set points to several practical test cases: prediction of transition from laminar to turbulent regime for the flow over a flat plate; flow around a circular cylinder; flow around the KVLCC2 tanker and current loads in shallow water for a LNG carrier. In most of these exercises, parameter uncertainty is assumed to be zero, which is an assumption often required for the so-called practical calculations due to the computational effort required to address it. Nonetheless, as an illustration of its application, the flow over the flat plate includes parameter uncertainty for the specification of the inlet turbulence quantities.
Examining Random Uncertainty Using a Newly Developed Power Spectrum Based Method
Authors: Brouwer Joris , Klinkenberg Yvette J. C. 
Published: October 2016

During steady state measurements, erratic oscillations can often be observed in the measured signals. For example, when measuring the ship-model resistance in a towing tank, oscillations might originate from vortex shedding, carriage control, rail imperfections, etc. These oscillations contribute to the random uncertainty of the observed mean value. The total observed random uncertainty can be caused by rapidly or slowly evolving oscillations. Rapidly evolving means that the periodicity is typically within the time frame of measurement, e.g. vortex shedding. Slowly evolving means that the periodicity is typically not contained within the available time frame of measurement, e.g. creep in a force sensor. The random uncertainty of the mean of a single measurement can be evaluated accurately when the rapidly evolving effects are dominant. The observed autocovariance of the signal can be used to find an uncertainty estimate for the signal as a whole [1]. In this paper, a new methodology to quantify the individual contribution of various spectral components to the random uncertainty is presented.
The new methodology is based on the power spectrum of a signal. The power spectrum only describes the energy content of all the rapidly evolving effects, while energy of slowly evolving effects is absent. For many stationary processes, individual spectral components of the power spectrum can be regarded uncorrelated or weakly correlated with each other. Each individual frequency component may be regarded as an uncorrelated band pass noise process. The uncertainty contribution of such processes to the mean value can be evaluated accurately, hence the spectral density of the process is directly correlated to the uncertainty of the mean; lowering the spectral density lowers the uncertainty. By quantifying the uncertainty contribution for each spectral component, various effects can be distinguished in the frequency domain and their individual contribution to the uncertainty of the mean can be determined. Using this information, sound decisions can be made to what effects should receive effort to lower the amplitude of oscillation and hence the random uncertainty.
This paper presents the newly developed power spectrum based method, called uncertainty spectrum, to determine the spectral contribution to the uncertainty of the mean and demonstrates the application of this method to ship-model resistance measurement data.
Development of a Double Joint Welding Procedure Specification for Fatigue Applications
Authors: Marines-Garcia Israel , Erezuma Emma , Mota-Solis Noe , Darcis Philippe P. , Quintanilla Hector M. 
Published: October 2016

One of the major concerns in terms of Structural Integrity for Steel Catenary Risers (SCR) or Fatigue Sensitive Flowlines (FSFL) consists on their strength to withstand dynamic loading along their service life. SCR and FSFL systems always experience more considerable fatigue loading due to floating structures adopted for deep and ultra-deep water oil and gas recovery, as well as for free spanning due to seabed geography and marine currents.
In this context, a Double Joint (DJ) Welding Procedure Specification (WPS) has been developed to comply with stringent fatigue requirements, as well as to assess their actual fatigue behavior. The benefits of having DJ are: improving the installation time (S-lay, J-lay or reel-lay) having half of the welding joint performed out of the firing line and reducing the need of Field Joint Coating by two, which results on decreasing project’s cost.
This DJ development is focused on a more productive WPS applicable for sour service environments and fatigue endurance requirements considering a Narrow Groove (NG) with J-Bevel design, STT® root pass, SAW for fill and cap passes in 1G welding position. The obtained WPS results are presented on an X65 Steel pipe grade, 273.1 mm OD and 25.4 mm WT.