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Aims Ablation of outflow tract ventricular arrhythmias may be limited by a deep intramural location of the arrhythmogenic source. This study evaluates the acute and long-term outcomes of patients undergoing ablation of intramural outflow tract premature ventricular complexes (PVCs). Methods and results This multicenter series included patients with structurally normal heart or nonischemic cardiomyopathy and intramural outflow tract PVCs defined by: (a) ≥ 2 of the following criteria: (1) earliest endocardial or epicardial activation < 20ms pre-QRS; (2) Similar activation in different chambers; (3) no/transient PVC suppression with ablation at earliest endocardial/epicardial site; or (b) earliest ventricular activation recorded in a septal coronary vein. Ninety-two patients were included, with a mean PVC burden of 21.5±10.9%. Twenty-six patients had had previous ablations. All PVCs had inferior axis, with LBBB pattern in 68%. In 29 patients (32%) direct mapping of the intramural septum was performed using an insulated wire or multielectrode catheter, and in 13 of these cases the earliest activation was recorded within a septal vein. Most patients required special ablation techniques (one or more), including sequential unipolar ablation in 73%, low-ionic irrigation in 26%, bipolar ablation in 15% and ethanol ablation in 1%. Acute PVC suppression was achieved in 75% of patients. Following the procedure, the PVC burden was reduced to 5.8±8.4%. The mean follow-up was 15±14 months and 16 patients underwent a repeat ablation. Conclusion Ablation of intramural PVCs is challenging; acute arrhythmia elimination is achieved in 3/4 patients, and non-conventional approaches are often necessary for success. more...

A calculus for scaled experimentation has recently appeared in the open literature founded on the continuous (metaphysical) concept of space scaling. The new theory for isotropic scaling (termed finite similitude) is a single-parameter theory that provides similitude rules that link unlimited numbers of scaled experiments to predict the behavior of any full-scale system. A facet of the theory is that it relates scalar, vectorial and tensorial coefficients and is therefore indirectly influenced by the choice of inertial-coordinate frames characterizing the full and scaled experiments. This feature is explored in this paper to relate objects that are skewed with a particular focus on thin-walled vibrating structures, which find widespread industrial usage but also benefit from anisotropic scaling in their thickness direction. The focus here is on the recently developed first-order finite similitude theory involving two scaled-down experiments for scaled vibrational analysis. The efficacy of the proposed scaling method is examined by means of analytical and numerical simulations. Case studies involving thin-walled plates and hollow beams, subject to free and forced vibration, confirm that titanium prototypes can be represented with high accuracy (∼0% error) by scaled models of identical and different materials (viz., steel and aluminum). more...

The wide-ranging product applications in the food and beverage (F&B) industry, owing to its rich taste and creaminess, are among the primary factors driving the table butter market. In line with this, the growing demand for table butter as a condiment or spread on toasted bread items is further catalyzing the market growth. more...

The escalating consumer concerns towards the spread of water-borne diseases are among the primary factors driving the bottled water market. Besides this, the elevating awareness regarding the health hazards of sugar and artificial sweeteners that are present in carbonated drinks is further catalyzing the market growth. Moreover, the emerging trend of premium bottled water variants is acting as another significant growth-inducing factor. more...

The expanding construction industry is primarily driving the medium-density fiberboard market. Additionally, MDF is comprised of superior quality wood fibers and is usually available at significantly lower prices when compared to its counterparts, including hardboard, particleboard, dimensional lumber, etc., which is further catalyzing the market growth. more...

The rising consumer inclination towards high-end and premium personal grooming products is primarily driving the US professional skincare market. Moreover, the widespread adoption of skin care regimes to protect the skin from any damage caused by dust, ultraviolet (UV) rays, humidity., etc., is also catalyzing the market growth. Besides this, numerous manufacturers are using organic and herbal product variants to expand their customer base, which is further augmenting the regional market. more...

The expanding construction sector and the growing number of housing, commercial, industrial, and mega real estate development projects are among the key factors driving the PVC pipes market. Besides this, the rising demand for PVC pipes in sewage and water utility services is further catalyzing the market growth. Moreover, PVC pipes offer high cost-efficiency, easy installation, and low maintenance costs by mitigating the need for welding, unlike the traditional metal pipes, which is acting as another significant growth-inducing factor. more...

The widespread adoption of outdoor illumination systems, across various commercial and industrial areas, including security perimeters, stadiums, warehouses, etc., owing to their capacity to withstand harsh conditions, such as vibrations, rough weather, external shocks, etc., is primarily driving the LED down lights market. Additionally, the increasing popularity of LED retrofitting for excellent lumen power and better service life at less wattage is further catalyzing the market growth. more...

The growing health consciousness among consumers is propelling the demand for functional foods that contain high quantities of proteins and other vital nutrients. This, in turn, is among the primary factors driving the GCC protein ingredients market. In addition to this, the escalating popularity of vegan, vegetarian, and gluten-free product variants is further catalyzing the market growth. Moreover, the emerging fitness trend and the inflating product usage in protein-rich foods, which are essential for muscle building and weight management, are acting as significant growth-inducing factors. more...

The elevating alcohol consumption levels across the globe are among the primary factors driving the glass bottles market. In addition to this, the growing adoption of glass-based packaging solutions in the personal grooming sector for catering to the safe and seamless transportation and storage of various fragrances and cosmetic products is further catalyzing the market growth. more...

The growing sales of passenger vehicles and the increasing product adoption as an alternative to fossil fuels are primarily driving the ethanol market. In line with this, the development of bioethanol, which is biodegradable, relatively less toxic, and does not cause environmental pollution when compared to conventional fuels, is further catalyzing the market growth. more...

The expanding information technology (IT) industry across the globe is primarily driving the laptops market. Besides this, the widespread adoption of bring-your-own-device (BYOD) trends by various organizations to ease operations is further stimulating the market growth. more...

The expanding number of power transmission and distribution plants is primarily driving the electrical wire market. Additionally, the widespread product adoption in electronic entertainment devices, heating, ventilation and air conditioning (HVAC) systems and lighting solutions in smart homes is further catalyzing the market growth. Besides this, the increasing utilization of electrical wires in underground cabling for utility distribution networks and to provide a connection between transformers and generators is acting as another significant growth-inducing factor. more...

The growing product adoption as a gelling agent to thicken the consistency of various fruit-based products, such as jams, marmalades, jellies, etc., is primarily driving the pectin market. Additionally, the escalating demand for natural and clean label ingredients, on account of the increasing consumer inclination towards functional supplements, is further catalyzing the market growth. more...

The escalating number of fast-food chains is among the primary factors driving the cheese market. In line with this, the growing demand for ready-to-eat (RTE) food items is further bolstering the market growth. Moreover, the emerging trend of Westernization of food consumption patterns, especially in developing countries, such as India and China, is acting as another significant growth-inducing factor. Apart from this, the expanding organized retail sector and the rising improvements in cold chain infrastructures are also augmenting the global market. more...

The rising product demand in the commercial and residential sectors, owing to the expanding construction industry, is among the key factors driving the float glass market. Besides this, float glass is utilized in architectural and interior design applications, such as flooring, ceiling, insulated glass, mirrors, reflective windows, tabletops, etc., which is further catalyzing the market growth. more...

The growing levels of power consumption across countries are among the primary factors driving the LED bulb market. Moreover, several government bodies are providing steep power subsidies to propel electrification rates, especially in rural areas, which is further catalyzing the market growth. more...

The growing levels of commercial livestock production are among the primary factors driving the US animal feed market. Additionally, the widespread product adoption as a source of energy and nutrition to support muscular activity and sustain life processes in the animals is further catalyzing the market growth. Besides this, the increasing consumer awareness towards the various health benefits of algae-based ingredients in animal feed is acting as another significant growth-inducing factor. more...

The elevating urbanization levels and the growing electrification rates are among the key factors driving the GCC power inverter market. In line with this, the rising demand for consumer electronic appliances and gadgets is further catalyzing the market growth. Moreover, the inflating need to ensure uninterrupted power supply, especially in urban areas, is propelling the usage of power inverters as alternate backup solutions in case of outages. Besides this, these products are noise-free and eco-friendly in nature since they do not emit carbon emissions and extinguish the need for gasoline, which is needed for running generators. more...

The expanding construction industry is among the primary factors driving the GCC gypsum board market. In line with this, the inflating demand for commercial and residential building projects, owing to the growing population and elevating urbanization levels, is further catalyzing the market growth. Moreover, the escalating number of renovation and restoration undertakings for structural complexes is acting as another significant growth-inducing factor. In addition to this, the emerging trend of wood-frame construction, which uses gypsum boards as essential components, is also bolstering the market growth. more...

The launch of various favorable policies by government bodies aimed at spreading awareness towards the usage of modern medicines for HIV treatments and early detection is among the key factors driving the GCC HIV drugs market. Besides this, the widespread adoption of advanced medical solutions is propelling the demand for HIV drugs that aid the immune system in keeping the levels of the virus at a minimal level, thereby leading to prolonged life expectancy in patients. more...

The escalating demand for on-the-go food products is among the key factors driving the GCC specialty paper market. In line with this, the widespread product adoption as a packaging material in the food and beverage (F&B) industry is further catalyzing the market growth. Besides this, the growing consumer inclination towards specialty paper alternatives, on account of the several stringent regulations related to the usage of plastic bags, is acting as another significant growth-inducing factor. more...

The increasing prevalence of chronic diseases, including obesity, diabetes, cardiovascular diseases (CVDs), etc., is primarily driving the self-care medical devices market. Additionally, the growing consumer inclination towards various self-care devices, such as wearable and smart trackers, to self-monitor their physical well-being is further catalyzing the market growth. Besides this, self-care medical devices aid in reducing the patient burden in terms of hospital visits for minor medical conditions and enable the timely diagnosis of an ailment which is acting as another significant growth-inducing factor. more...

The widespread product adoption as a source of backup or emergency power across the industrial sector is primarily driving the US portable gas generator market. In line with this, the increasing utilization of standby power sources to meet the inflating need for reliable and regular electricity supply is further catalyzing the market growth. Moreover, the launch of numerous favorable policies by the government bodies to promote the usage of environment-friendly gas generators that can be powered by biofuels and other sustainable energy sources, on account of the growing consumer concerns towards harmful greenhouse gas emissions, is acting as another significant growth-inducing factor. more...

The elevating consumer awareness towards the importance of regular household cleaning is primarily driving the glass cleaning spray market. Additionally, the widespread product adoption, owing to its simple and disposable nature, to ensure a clean and spotless home at minimal effort is further catalyzing the market growth. Besides this, the development of glass cleaning sprays that are skin-friendly, biodegradable, and possess a thick formulation for better dispensing control is acting as another significant growth-inducing factor. more...

The growing consumer inclination towards ready-to-eat food products, on account of the rising hectic lifestyles, is primarily driving the cakes and pastries market. Additionally, the widespread adoption of various bakery items, including cakes, pastries, pies, etc., that are sugar-free, gluten-free, whole-wheat, etc., by health-conscious individuals is further catalyzing the market growth. Besides this, the increasing utilization of cakes and pastries on numerous ceremonial and formal occasions, owing to their palatability, appearance, easily digestible nature, etc., is acting as another significant growth-inducing factor. more...

The global weight management market is primarily driven by the rising prevalence of obesity and weight-related health issues. Besides this, the expanding fast-food industry, hectic work schedules, and a lack of physical activity are resulting in numerous lifestyle diseases, which in turn are putting a significant strain on public healthcare budgets. These factors have prompted the government bodies across several countries to host health awareness and wellness programs, thereby augmenting the demand for weight management services. more...

The increasing demand for ready-to-eat (RTE) and ready-to-cook (RTC) food items is among the key factors driving the frozen fish and seafood market. Besides this, the elevating consumer awareness towards the health benefits of consuming seafood is further catalysing the market growth. Moreover, the escalating demand for frozen seafood as a thickening agent in numerous food-processing applications is acting as another significant growth-inducing factor. more...

Measurements of acoustic properties of sound absorbing materials in impedance tubes show poor reproducibility, which was demonstrated in round robin tests. The impedance tube measurements are standardized but lack precise definitions of the actual measurement setup, specimen preparation, and other factors that introduce uncertainty in practice. In this paper, machine learning models identify those factors that mostly affect the sound absorption coefficient from a large data set of more than 3000 absorption spectra measured in one impedance tube. The specimens are manufactured from one polyurethane foam, and different cutting technologies, different operators, different specimen diameters, different specimen thicknesses, and two different approaches to mount the specimens in the impedance tube are considered. Explainable machine learning techniques allow the identification and quantification of the most influential factors and, furthermore, the frequency ranges that are the most affected by the choice of these setup factors. The results indicate that besides the specimen thickness, also the operator affects the absorption coefficient by a directional and non-random relationship. Hence, it needs to be controlled carefully. The method proves to be a promising pathway for knowledge discovery from acoustic measurement data using explainability approaches for machine learning models. more...

Designing the vibroacoustic properties of thin-walled structures is of particularly high practical relevance in the design of vehicle structures. The vibroacoustic properties of thin-walled structures, e.g., vehicle bodies, are usually designed using finite element models. Additional development effort, e.g., experimental tests, arises if the quality of the model predictions are limited due to inherent model uncertainty. Model uncertainty of finite element models usually occurs in the modeling process due to simplifications of the geometry or boundary conditions. The latter highly affect the vibroacoustic properties of a thin-walled structure. The stiffness of the boundary condition is often assumed to be infinite or zero in the finite element model, which can lead to a discrepancy between the measured and the calculated vibroacoustic behavior. This paper compares two different boundary condition assumptions for the finite element (FE) model of a simply supported rectangular plate in their capability to predict the vibroacoustic behavior. The two different boundary conditions are of increasing complexity in assuming the stiffness. In a first step, a probabilistic model parameter calibration via Bayesian inference for the boundary conditions related parameters for the two FE models is performed. For this purpose, a test stand for simply supported rectangular plates is set up and the experimental data is obtained by measuring the vibrations of the test specimen by means of scanning laser Doppler vibrometry. In a second step, the model uncertainty of the two finite element models is identified. For this purpose, the prediction error of the vibroacoustic behavior is calculated. The prediction error describes the discrepancy between the experimental and the numerical data. Based on the distribution of the prediction error, which is determined from the results of the probabilistic model calibration, the model uncertainty is assessed and the model, which most adequately predicts the vibroacoustic behavior, is identified. more...

Engineers often use similitude analyses to design small scale models for experimental tests or to design size ranges of mechanical structures such as drive technology systems. This paper is concerned with similitude analysis methods for vibration analyses of rectangular plates. If their geometry is scaled by different factors (distorted similitude), the scaling laws approximate the actual vibration responses with a certain accuracy only. This paper introduces a performance measure that reliably assesses how well the scaling laws approximate the actual vibration responses of rectangular plates. This measure, the so-called Mahalanobis distance, applies in a-posteriori analyses, where the vibration responses obtained from the scaling laws are compared to the actual ones. Numerical and experimental investigations on vibrating rectangular plates validate that the Mahalanobis distance is suitable to assess the performance of similitude analyses. The Mahalanobis distance can be linked to the geometrical properties of the rectangular plates in order to define a maximum permissible distortion of the geometry. Scaling laws approximate the vibration responses of the rectangular plates sufficiently well up to this maximum permissible distortion. Furthermore, the performance of two different state-of-the-art similitude analysis methods is compared. Both similitude analysis methods are found to perform well up to the maximum permissible amount of geometrical distortion. more...

In structures, high vibration levels can destroy components; therefore, the reduction of the vibration levels represents a fundamental target in the industrial field. The structural intensity (STI) field provides information about the energy flow that propagates within a structure. It shows the position of dampers in structures, thus, it can be used for solving structure-borne noise problems. The analysis of the energy distribution on a structure allows to understand where to implement locally concentrated modifications introducing damping patches in order to reduce structure-borne noise. The aim of this paper is to investigate the structural intensity in composite structures and to evaluate the influence of some modeling parameters, such as mesh density, structural damping, etc., on the accuracy of the results. In this paper, numerical investigations on the STI in a fiber composite plate are carried out. Two different numerical models are considered: the first one with solid elements, the second one with shell elements. The two-dimensional model does not allow to analyze and study the composite plate on micro level. The first law of thermodynamics allows to define the accuracy of the STI evaluations. The investigation on two-dimensional and three-dimensional composite structure modeling presents the limits and the advantages of the two different types of approach. The different characteristics of the STI fields provided by these models are analyzed in order to understand the difference between local and global approach. more...

Noise and vibration engineering faces increasing demands of customers such as noise limits or comfort issues and also requires cost-efficient and adaptable design engineering methods due to shorter product life cycles. Taking advantage of similitudes of designs can address these needs by using scaled prototypes in experimental investigations or by designing size ranges and kits. However, a reliable prognosis of noise and vibration of an original design requires scaling laws that transfer the measurement results from the scaled prototype to the original design or from one design to another one within a size range. Similitude analysis lacks efficient and straightforward methods to derive scaling laws, thus, contradicting the demand for cost-efficient design engineering methods. Furthermore, scaling laws are often limited to complete similitude conditions such as equal damping values of the scaled prototype and of the original design or perfect geometrical similitude of a size range, which are hardly fulfilled in practice. This thesis aims at developing a procedure to straightforwardly derive scaling laws of mechanical structures by combining similitude analysis with sensitivity analysis, which determines the effect of design parameters on the vibration behavior of a mechanical structure. From this, the noise and vibration behavior of mechanical structures can be predicted even if incomplete similitude conditions persist. Similitude analysis and sensitivity analysis methods are first illustrated by potential applications in noise and vibration engineering using a double mass oscillator as a comprehensible example of a mechanical structure. A new scaling method is developed that combines similitude analyses with sensitivity analyses. This allows for deriving scaling laws, which incorporate sensitivities as coefficients. The scaling laws of rectangular plates in complete similitude are directly derived from analytical and finite element calculations for global and local vibration responses such as surface-averaged frequency response functions or vibration velocities at a local receiver point. These scaling laws match those derived from state-of-the-art similitude analysis methods, which verifies the new scaling method. Applying the new scaling method to plate-like structures in complete similitude demonstrates that scaling laws can be straightforwardly derived, whereas state-of-the-art similitude analysis methods would be too time-consuming. The scaling laws derived from the new scaling method accurately predict the vibration responses of scaled structures using the vibration responses of an original structure, which are obtained from numerical calculations or experimental measurements. The new scaling method even replicates the vibration responses of structures in geometrically incomplete similitude sufficiently well by using another scaled structure, which is in complete similitude to the original structure. In order to assess the accuracy of the scaled vibration responses an error measure is developed and validated in a-posteriori analyses. Finally, a size range of gear boxes in geometrically incomplete similitude demonstrates that the natural frequencies of an entire size range can be predicted with a sufficient accuracy by the new scaling method. The new scaling method can be enhanced towards kits since the natural frequencies of the gear boxes with various lumped masses attached can be replicated sufficiently well. more...

A multicore fiber (MCF) based temperature sensor was fabricated and packaged into a stainless-steel tube to protect the bare-fiber, and it offers a commercial friendly form factor. The sensor displayed a periodic supermode interference pattern that red-shifts with increasing temperature, which was used to calibrate the sensor. Additionally, an economical photodiode-based interrogator was fabricated from off-the-shelf parts and used to calibrate the sensor in both liquid and gas mediums. The response time to changes in temperature for the MCF sensor was found to be an order of magnitude faster than a thermocouple of identical diameter, 0.09 s compared to >1.0 s, respectively. more...

The Genuine Progress Indicator (GPI), a version of the Index of Sustainable Economic Welfare (ISEW), is a significantly more comprehensive approach to assessing economic progress than conventional measures like gross domestic product (GDP). GPI adjusts for income distribution effects, the value of household and volunteer work, costs of mobility and pollution, and the depletion of social and natural capital. ISEW or GPI have been estimated for several countries around the world and a few Canadian provinces, but we report here on the first multi-scale application at the city, county and state levels in Vermont, USA. We show that it is feasible to apply the GPI approach at these smaller scales and to compare across scales and with the national average. Data limitations and problems still exist, but potential solutions to these problems also exist. All three Vermont scales had significantly higher GPI per capita since 1980 than the national average, indicating the major differences that can exist within countries. The GPI per capita for all Vermont scales was similar to the national average in the 1950–1980 period, but more than twice the national average by 2000. The main factors explaining this difference had to do with Vermont’s much better environmental performance than the national average in the post-1980 period. D 2004 Elsevier B.V. All rights reserved. more...

The New World monkey (NWM),Callithrix jacchus, a preferred model in medical research, displays an interesting endocrine regulation of reproduction: LH, the heterodimeric glycoprotein hormone, is functionally replaced by the chorionic gonadotropin (CG), a hormone indispensable for establishment of pregnancy in humans and normally expressed in the placenta. In the marmoset pituitary, the expression of the β-subunit (CGB) gene is regulated similar to human LH β-subunit, but its placental regulation is unknown. This study intended to decipher the underlying mechanism of tissue-specific expression ofCGBin the marmoset placenta. We identified a new placental transcriptional start site, described a new, previously undiscovered exon, and define a novel placental core promoter in the marmosetCGBgene. This promoter contains a TATA box and binding sites for activating protein 2 and selective promoter factor 1, the latter acting synergistically by forming a regulation cassette. Differential first exon usage directed the tissue-specific expression. Methylation analyses revealed a tissue-specific pattern in the placental promoter indicating additional epigenetic regulation of gene expression. Our findings point toward a hitherto unknown evolutionary plasticity in the LH/CG hormonal system in NWM, which could be used as a model to study human CGB regulation in clinical pathologies. more...

Natriuretic peptide (NP) levels (B-type natriuretic peptide (BNP) and N-terminal proBNP) are now widely used in clinical practice and cardiovascular research throughout the world and have been incorporated into most national and international cardiovascular guidelines for heart failure. The role of NP levels in state-of-the-art clinical practice is evolving rapidly. This paper reviews and highlights ten key messages to clinicians: NP levels are quantitative plasma biomarkers of heart failure (HF). NP levels are accurate in the diagnosis of FIR NP levels may help risk stratify emergency department (ED) patients with regard to the need for hospital admission or direct ED discharge. NP levels help improve patient management and reduce total treatment costs in patients with acute dyspnoea. NP levels at the time of admission are powerful predictors of outcome in predicting death and re-hospitalisation in HF patients. NP levels at discharge aid in risk stratification of the HF patient. NP-guided therapy may improve morbidity and/or mortality in chronic HF. The combination of NP levels together with symptoms, signs and weight gain assists in the assessment of clinical decompensation in HE NP levels can accelerate accurate diagnosis of heart failure presenting in primary care. NP levels may be helpful to screen for asymptomatic left ventricular dysfunction in high-risk patients. Published by Elsevier B.V. on behalf of European Society of Cardiology. more...