bluuebunny/crossref_metadata_2025_split huggingface dataset:
VV′ Alternans Triplets on Near‐Field ICD Intracardiac Electrogram is Associated with Mortality
Authors: BAUMERT MATHIAS , KABIR MUAMMAR M. , DALOUK KHIDIR , HENRIKSON CHARLES A. , TERESHCHENKO LARISA G. 
Published: March 2015

BackgroundIn heart failure patients with implantable cardioverter defibrillator (ICD) the risk of death from causes other than tachyarrhythmia is substantial. Benefit from ICD is determined by two competing risks: appropriate ICD shock or nonarrhythmic death. The goal of the study was to test predictors of competing outcomes.MethodsPatients with structural heart disease (N = 234, mean age 58.5 ± 15.1; 71% men, 80% whites, 61% ischemic cardiomyopathy) and primary (75%) or secondary prevention ICD underwent a 5‐minute baseline near‐field electrogram (NF EGM) recording. VV′ alternans triplets were quantified as a percentage of three sinus VV′ cycles sequences of “short‐long‐short” or “long‐short‐long” order. Appropriate ICD shock for fast ventricular tachycardia (FVT, cycle length ≤240 ms)/ventricular fibrillation (VF) and composite nonarrhythmic death (pump failure death or heart transplant) served as competing outcomes.ResultsOver a median follow‐up of 2.4 years, 26 patients (4.6% per person‐year of follow‐up) developed FVT/VF with ICD shock, and 35 (6.3% per person‐year of follow‐up) had nonarrhythmic death. In competing risk analysis, after adjustment for demographics, left ventricular ejection fraction, New York Heart Association class, cardiomyopathy type, use of class I antiarrhythmics, and diabetes, increased percentage of VV′ alternans triplets (>69%) was associated with nonarrhythmic death (subhazard ratio [SHR] 2.09; 95% confidence interval [CI] 1.03–4.23; P = 0.041), rather than with FVT/VF (SHR 1.05; 95% CI 0.45–2.46; P = 0.901). Risk of nonarrhythmic death was especially high in diabetics with VV′ alternans triplets in the highest quartile (SHR 3.46; 95% CI 1.41–8.50; P = 0.007).ConclusionIn ICD patients with structural heart disease sinus VV′ alternans triplets on NF EGM is independently associated with nonarrhythmic death, rather than with FVT/VF.
Pleomorphism during Ventricular Tachycardia: A Distinguishing Feature between Cardiac Sarcoidosis and Idiopathic VT
Authors: PANDA SUBHANARAYAN , KAUR DALJEET , LALUKOTA KRISHNAMOHAN , SUNDAR GOMATHI , PAVRI BEHZAD B. , NARASIMHAN CALAMBUR 
Published: March 2015

BackgroundVentricular tachycardia (VT), a common manifestation of cardiac sarcoidosis (CS), is associated with high morbidity and mortality. It could be mistaken for idiopathic VT (IVT) in the absence of systemic manifestations and overt cardiac structural abnormality. We studied the electrocardiogram (ECG) characteristics of VT in CS that may distinguish from IVT and also explored the relationship of the ECG characteristics with imaging findings in patients with CS.Methods and ResultsTwelve‐lead ECG characteristics of VT in CS patients (Group I = 37) were compared with IVT (Group II = 49). QRS duration, axis, morphology, VT cycle length, and cycle length variation (CLV) were analyzed.In Group I, 18 (49%) had pleomorphic VT (PLVT) and none in Group II. CLV was seen only in Group I (24%). Mean QRS duration (milliseconds) and cycle length (milliseconds) were greater in Group I (QRSd 152.49 [39.3] vs 140.9 [19.2]) and (332.2 [136.5] vs 312.9 [56.2]), the differences not statistically significant.In Group I, myocardial scar was present in 22 of 25 patients and myocardial inflammation in 28 of 29 patients as assessed by cardiac magnetic resonance imaging (delayed enhancement) and 18‐fluorodeoxyglucose positron emission computed tomography, respectively. PLVT was seen more commonly in patients with involvement of >1 myocardial region than focal involvement (58% and 30%, respectively, with myocardial scar and 50% and 40%, respectively, with myocardial inflammation).ConclusionPleomorphism and CLV during VT may be distinguishing features between IVT and VTs of CS origin.
Outcome of Patients with Advanced Heart Failure Who Receive Device‐Based Therapy for Primary Prevention of Sudden Cardiac Death: Insights from the Israeli ICD Registry
Authors: SULEIMAN MAHMOUD , GOLDENBERG ILAN , SAMNIAH NIMER , ROSSO RAPHAEL , MARAI IBRAHIM , PEKAR ALEXANDER , KHALAMEIZER VLADIMIR , MILITIANU ARIE , GLIKSON MICHAEL 
Published: March 2015

BackgroundRandomized clinical trials have shown conflicting data on the benefit of implantable cardioverter defibrillator (ICD) for primary prevention of sudden cardiac death in patients with more advanced heart failure (HF) symptoms. Using the Israeli ICD Registry data, we sought to examine the effect of HF functional class on the outcome of patients who receive device therapy in a real‐world setting.MethodsThe association between HF functional class (categorized as baseline New York Heart Association [NYHA] functional class I and II in [61%] vs class III and IV in [39%]) and clinical outcomes was assessed among 913 patients who received an ICD (n = 514) or a cardiac resynchronization therapy with a defibrillator (CRT‐D; n = 399) device and were prospectively followed in the Israeli ICD Registry between July 2011 and June 2013.ResultsThe risk associated with advanced HF functional class was significantly different in ICD and CRT‐D recipients. In the former group, patients with NYHA classes III and IV experienced >3‐fold increased risk of HF or death (hazard ratio [HR] = 3.28; P < 0.001), whereas among CRT‐D recipients the risk was similar between patients with NYHA III/IV and those with less advanced HF symptoms (HR = 0.97 [95% confidence interval (CI) 0.54–1.78]; P = 0.42; P value for NYHA functional class by device type interaction = 0.002). The risk for ventricular arrhythmia (VA) was significantly lower among patients with more advanced NYHA functional class, regardless of device type (overall HR = 0.52; 95% CI 0.33–0.91; P = 0.04).ConclusionOur findings suggest that patients with less advanced HF symptoms experience a greater risk for VA and the development of HF is attenuated in CRT‐D recipients with more advanced NYHA functional class.
Going mobile: Non‐cell‐autonomous small RNAs shape the genetic landscape of plants
Authors: Pyott Douglas E. , Molnar Attila 
Published: March 2015

SummaryRNA silencing is a form of genetic regulation, which is conserved across eukaryotes and has wide ranging biological functions. Recently, there has been a growing appreciation for the importance of mobility in RNA silencing pathways, particularly in plants. Moreover, in addition to the importance for mobile RNA silencing in an evolutionary context, the potential for utilizing mobile short silencing RNAs in biotechnological applications is becoming apparent. This review aims to set current knowledge of this topic in a historical context and provides examples to illustrate the importance of mobile RNA silencing in both natural and artificially engineered systems in plants.
The Odense Child Cohort: Aims, Design, and Cohort Profile
Authors: Kyhl Henriette Boye , Jensen Tina Kold , Barington Torben , Buhl Susanne , Norberg Lene Annette , Jørgensen Jan Stener , Jensen Ditlev Frank Granhøj , Christesen Henrik Thybo , Lamont Ronald F. , Husby Steffen 
Published: March 2015

AbstractBackgroundThe importance of the environment on the development of the fetus and infant throughout early life is increasingly recognised. To study such effects, biological samples and accurate data records are required. Based on multiple data collection from a healthy pregnant population, the Odense Childhood Cohort (OCC) study aims to provide new information about the environmental impact on child health by sequential follow‐up to 18 years of age among children born between 2010 and 2012.MethodsA total of 2874 of 6707 pregnancies (43%) were recruited between January 2010 and December 2012. Three hundred seventy‐four have since left the study, leaving 2500 active families. The non‐participants act as controls contributing data through local registries. Biological material, questionnaires, and registry data were compiled. Anthropometric data and other physical data were collected.ResultsTwo thousand five hundred families actively participated in the study with 2549 children. Sixty‐four per cent of the fathers and 60% and 58% of the mothers, respectively, donated a blood sample at 10 and 28 weeks of gestation. On average, 69% completed questionnaires, 78% of the children were regularly examined, and had a blood sample taken (46%). The participating pregnant women differed from the non‐participants in several respects: age, body mass index, smoking, parity, education, and ethnicity. The infants were comparable with respect to gender and mode of delivery.ConclusionsThe OCC provides material for in‐depth analysis of environmental and genetic factors that are important for child health and disease. Registry data from non‐participating women and infants are available which ensures a high degree of comparable data.
Utilization of maternal health services among adolescent women in Bangladesh: A scoping review of the literature
Authors: Shahabuddin A. S. M. , Delvaux Thérèse , Abouchadi Saloua , Sarker Malabika , De Brouwere Vincent 
Published: March 2015

AbstractObjectiveTo understand the health‐seeking behaviour of adolescent women in Bangladesh with respect to the use of maternal health services.MethodsLiterature review of seven electronic databases: PubMed, ISI Web of Knowledge, PsycINFO, Embase, CINAHL, POPLINE and Global Health. Studies published in English between 1990 and 2013 which describe Bangladeshi adolescent women's healthcare‐seeking behaviour during pregnancy, delivery and post‐partum were included.ResultsTwelve studies were included in this review. 11 used quantitative methods and one used a mixed‐methods approach. All studies included married adolescent women only. Women with lower educational levels are less likely to seek skilled maternal health services than those with higher levels of education. Use of maternal health services is also less common among rural married adolescent women than women in urban areas. Being part of the richest bands of wealth, having had previous experiences of childbirth and higher women's autonomy positively influence the use of skilled maternal health services among married adolescent women in Bangladesh. Antenatal care is a key predictor of the use of skilled birth attendants for delivery and post‐natal care.ConclusionMaternal health‐related programmes should be designed targeting rural and uneducated married adolescent women in Bangladesh. More qualitative investigations are required to broaden our understanding on maternal health‐seeking behaviour of both married and unmarried adolescent women.
In vitro affinity reduction of biologic response modifiers from production buffy coat platelets exposed to recombinant protein receptors
Authors: Sandgren Per , Rönnmark Jenny , Axelsson Jonas 
Published: March 2015

BACKGROUNDRecent studies link biologic response modifiers found in donor platelet (PLT) concentrates to transfusion reactions. We tested a novel method to deplete BRMs from PLT concentrates using apheresis.STUDY DESIGN AND METHODSWhole blood from 25 donors was treated to yield PLTs for in vitro measurements on Days 2, 5, and 7. On Day 7, PLTs were filtrated through columns with either antibody‐coated agarose or rh‐megalin bound to antibody‐coated agarose. In addition, we also tested the naked matrix (agarose) and another apheresis surface containing rh‐cubilin bound to agarose. Megalin and cubilin are parts of the protein complex mediating BRM endocytosis in the human kidney.RESULTSCompared to before filtration (951 × 109 ± 41 × 109 cells/L), PLT numbers decreased slightly after filtration over both naked (859 × 109 ± 38 × 109) and antibody‐coated (848 × 109 ± 41 × 109) matrices (both p < 0.001 vs. before). Concentrations of interleukin (IL)‐1β, IL‐12 (p40), IL‐12 (p70), and IL‐7 all decreased by approximately 40% even in the absence of a recombinant surface. After filtration over rh‐cubilin, but not rh‐megalin, concentrations of IFN‐γ, IL‐1β, tumor necrosis factor‐α, IL‐12, and IL‐7 all further decreased by 30% to 50%.CONCLUSIONIn a pilot study of in vitro apheresis to deplete BRMs, we found that cell numbers and function remained largely unaffected by filtration. Significant reductions in BRMs occurred already with agarose. However, apheresis with the multiligand receptor rh‐cubilin was able to further decrease concentrations.
Reconstructing the invasion of Cyperus esculentus in Central Europe
Authors: Follak S , Aldrian U , Moser D , Essl F 
Published: March 2015

SummaryCyperus esculentus (yellow nutsedge) is a serious weed in agriculture worldwide and observational data suggest that it has recently started to spread rapidly in Central Europe. We studied its spatiotemporal invasion pattern, rate of spread and habitat affiliation in Austria, Germany and Switzerland, using retrospective distribution data from various sources and a method that accounts for sampling bias. In total, we found 265 records of C. esculentus since 1900. Multiple accidental introductions, coupled with subsequent regional radial expansion, describe the spatiotemporal range expansion of C. esculentus in the study area. Cumulative number of records and of the number of invaded grid cells showed a continuous increase, but spread has become more pronounced recently (>2005). Invasion hotspots were located in the warmest regions of the study area, as well as in regions with an oceanic climate. On average, the rate of spread within these invasion hotspots ranged between 3.1 and 5.7 km per year. Cyperus esculentus was primarily found on arable land, while other habitats have been rarely invaded. The integration of different data sources improved the cover of distribution data and was useful for reconstructing the incipient and recent invasion phase of C. esculentus. The data suggest that control may be best achieved by preventing long‐range dispersal and containing or eradicating incipient infestations of C. esculentus.
The Application of Convective Cooling Enhancement of Span-Wise Cooling Holes in a Typical First Stage Turbine Blade
Authors: Stankiewicz D. J. , Kirkham T. R. 
Published: March 2015

A technique of heat transfer enhancement is investigated whereby the internal span-wise cooling passages of a typical first stage gas turbine blade are modified by the introduction of circumferential ribs.
The technique is verified by the use of a test rig incorporating a heated internally ribbed tube operating at the same range of Mach and Reynolds numbers as the turbine blade as well as by a test rig incorporating actual production blades immersed in a heated oil bath.
Thermal Strain Tolerant Abradable Thermal Barrier Coatings
Authors: Strangman T. E. 
Published: March 2015

Thermal barrier coatings (TBCs) are applied to hot gas path surfaces to reduce metal temperatures and thermal stresses for improved turbine component durability. Improvements in engine performance are achieved when TBCs enable reductions in cooling air usage and turbine blade tip-shroud clearances.
This paper describes the development of thick TBCs with superior strain tolerance. A pattern of grooves or slant steps incorporated into the surface to be coated enables the development of shadow gaps in the ceramic layer during plasma spray deposition. These gaps segment the TBC, permitting ceramic-metal thermal expansion mismatch and thermal strains to be accommodated by free expansion.
Implanted Component Faults and Their Effects on Gas Turbine Engine Performance
Authors: MacLeod J. D. , Taylor V. , Laflamme J. C. G. 
Published: March 2015

Under the sponsorship of the Canadian Department of National Defence, the Engine Laboratory of the National Research Council of Canada (NRCC) has established a program for the evaluation of component deterioration on gas turbine engine performance. The effort is aimed at investigating the effects of typical in-service faults on the performance characteristics of each individual engine component. The objective of the program is the development of a generalized fault library which will be used with fault identification techniques in the field, to reduce unscheduled maintenance.
To evaluate the effects of implanted faults on the performance of a single spool engine, such as an Allison T56 turboprop engine, a series of faulted parts were installed. For this paper the following faults were analyzed:
a) 1st stage turbine nozzle erosion damage,
b) 1st stage turbine rotor blade untwist,
c) compressor seal wear,
d) 1st and 2nd stage compressor blade tip clearance increase.
This paper describes the project objectives, the experimental installation, and the results of the fault implantation on engine performance. Discussed are performance variations on both engine and component characteristics. As the performance changes were significant, a rigorous measurement uncertainty analysis is included.
The Use of Gaseous Fuels on Aero-Derivative Gas Turbine Engines
Authors: Mathieu Philippe , Pilidis Pericles 
Published: March 2015

In this paper, the use of various gaseous fuels in aero-derivative gas turbine engines is analysed. The gases investigated are natural gas and three coal synthetic gases of calorific values which are significantly lower than that of natural gas.
The analysis is carried out employing natural gas fuel as a yardstick for comparison. Due to the lower calorific values of synthetic gases, the mass flow balance between compressors and turbines is altered. This in turn affects the matching of the components and the overall performance of a gas turbine engine. The engines examined are a single spool gas generator with a free power turbine and the double engine described in a previous paper.
The main conclusion drawn from this analysis is that, for a given power output, the use of synthetic gases will result in an erosion of surge margins and in a reduction of the overall efficiency of the power plant.
Two-Phase Flow Correlations in Air/Oil Systems of Aero Engines
Authors: Zimmermann H. , Kammerer A. , Fischer R. , Rebhan D. 
Published: March 2015

A strategy is outlined on how to introduce two-phase flow correlations into air/oil system calculations for aero engines.
The importance of two-phase flow effects is highlighted by demonstrating their particular significance for the high altitude performance of a vent system.
For air/oil mixtures very little can be obtained from the literature and correlations derived from air/water test results have to be corrected. For critical flow conditions in restrictors an improved method is developed. Some test data obtained for air/oil mixtures show, that the proposed correlations agree fairly well.
Furthermore, it is shown how numerical methods for this complex field of fluid dynamics can be used in the future by the example of phase demixing by centrifugal forces.
An Analytical Method for the Fault Diagnosis of Axial Multistage Compressors
Authors: Massardo Aristide 
Published: March 2015

A deterministic approach for troubleshooting in axial multistage flow compressors, that is to say, the solution of the diagnostic or inverse problem is presented.
The approach utilizes a model which is capable of predicting the compressor performance with and without faults — solution of analysis or direct problems — previously developed and tested in several applications. The diagnostic problem solution, where the actual compressor performance is known, allows the type, level and position of a fault to be determined.
The novel method is presented and described in detail. The possibility to integrate this deterministic approach with heuristic diagnostic procedures, to take into account more complex fault configurations, is also discussed.
Influence of Unsteady Effects on the Measurements in a Transonic Axial Compressor
Authors: Paulon Jacques , Zhang Zhifang , Jia Pingfang , Meng Jingfei 
Published: March 2015

Interaction phenomena between rotor and stator are unavoidable in advanced compressors and their effects increase with the performances of the turbomachines.
Until now, it was not possible to quantify the interaction effects, but with the development of 3-D unsteady computation codes in a complete stage, it is possible to know, in detail, the flow field through the machine and to make evident and to explain the difficulties encountered in measuring the flow parameters.
A study has been conducted in this way at ONERA, on an axial transonic compressor stage. The computations have been made with a simulation of the losses; in this manner, the overall computed and measured performances of the compressor are the same.
A detailed analysis of the unsteady computation results makes evident, between rotor and stator, large variations of some parameters of the flow as a function of time but also as a function of the axial and tangential relative position of steady probes and stator blades. Unsteady measurements made on another transonic machine confirm the indications given by these computations.
Temperature Effects on Fuel Thermal Stability
Authors: Chin J. S. , Lefebvre A. H. , Sun F. T.-Y. 
Published: March 2015

The thermal stability characteristics of four kerosine-type fuels are examined using a heated-tube apparatus which allows independent control of fuel pressure, fuel temperature, tube-wall temperature, and fuel flow rate. It is a closed loop system, and fuet flows through the heated tube for periods ranging from 6 to 22 hrs. The deposition rates of carbon on the tube walls are measured by weighing the tube before and after each test.
The results obtained show that tube-wall and fuel temperatures both have a marked influence on deposition rates, the impact of fuel temperature being stronger than that of wall temperature. It is also found that deposition rates increase continuously with increases in tube-wall temperature. This finding contradicts the results of previous studies which had led to the conclusion that deposition rates increase with increase in wall temperature up to a certain value beyond which any further increase in wall temperature causes the deposition rate to decline.
The Transfer Number of Hydrocarbon Liquids
Authors: Odgers J. , Kretschmer D. 
Published: March 2015

The Transfer Number (B) assumes considerable importance in the evaporation and diffusion of fuels prior to their combustion. Quite often the Transfer Number is assumed to be a constant for a given fuel. These notes examine the feasibility of this assumption New correlations have been derived for the specific heats of the liquid fuels and their latent heats, over a wide range of temperatures and pressures, as also the effects of pressure upon the boiling characteristics. New prediction techniques are also proposed for critical temperatures and pressures.
Taking note of the above correlations, it becomes possible to assess the values of B for a wide range of combustor operating conditions for any given fuel. The significance of these variations upon the probable combustion behaviour of the fuels is then commented upon. The results show that the assumption of a constant value for B could lead to a significant mis-interpretation of combustion behaviour due to operating conditions and/or the use of different fuels.