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Noack Thilo T Department of Cardiac Surgery, University Heart Center Leipzig, Struempellstrasse 39, 04289 Leipzig, - - 2013
The high complexity of the mitral valve (MV) anatomy and function is not yet fully understood. Studying especially the dynamic movement and interaction of MV components to describe MV physiology during the cardiac cycle remains a challenge. Imaging is the key to assessing details of MV disease and to studying ...
Graser B - - 2013
   Over 40,000 annuloplasty rings are implanted each year in the USA to treat mitral regurgitation. However, the used measuring techniques to select a suitable annuloplasty ring are imprecise and highly depending on the expert's experience. This can cause a re-occurrence of the mitral regurgitation or an annuloplasty ring dehiscence, and ...
Addetia Karima - - 2013
Differentiating between mitral valve (MV) prolapse (MVP) and MV billowing (MVB) on two-dimensional echocardiography is challenging. The aim of this study was to test the hypothesis that color-coded models of maximal leaflet displacement from the annular plane into the atrium derived from three-dimensional transesophageal echocardiography would allow discrimination between these ...
Rubod C - - 2013
Genital prolapse remains a complex pathological condition. Physiopathology remains poorly understood, aetiology is multi-factorial, surgery is not always satisfying, as the rate of relapse cannot be overlooked. More over a good anatomical result will not always guarantee functional satisfaction. The aim of our study is to have a better understanding ...
Teodoro Tiago Quevedo - - 2013
Accurate relativistic adapted Gaussian basis sets (RAGBSs) for 87 Fr up to 118 Uuo atoms without variational prolapse were developed here with the use of a polynomial version of the Generator Coordinate Dirac-Fock method. Two finite nuclear models have been used, the Gaussian and uniform sphere models. The largest RAGBS ...
Sprouse Chad - - 2013
This study is concerned with the development of patient-specific simulations of the mitral valve that use personalized anatomical models derived from 3D Transesophageal Echocardiography (3D TEE). The proposed method predicts the closed configuration of the mitral valve by solving for an equilibrium solution that balances various forces including blood pressure, ...
Siefert Andrew W - - 2013
Patient-specific models of the heart's mitral valve (MV) exhibit potential for surgical planning. While advances in 3D echocardiography (3DE) have provided adequate resolution to extract MV leaflet geometry, no study has quantitatively assessed the accuracy of their modeled leaflets vs. a ground-truth standard for temporal frames beyond systolic closure or ...
Gavrovska Ana - - 2013
Phonocardiography has shown a great potential for developing low-cost computer-aided diagnosis systems for cardiovascular monitoring. So far, most of the work reported regarding cardiosignal analysis using multifractals is oriented towards heartbeat dynamics. This paper represents a step towards automatic detection of one of the most common pathological syndromes, so-called mitral ...
Rausch Manuel K - - 2012
Alterations in mitral valve mechanics are classical indicators of valvular heart disease, such as mitral valve prolapse, mitral regurgitation, and mitral stenosis. Computational modeling is a powerful technique to quantify these alterations, to explore mitral valve physiology and pathology, and to classify the impact of novel treatment strategies. The selection ...
Verberkmoes Niels J NJ Department of Cardio-Thoracic Surgery, Catharina Hospital, Eindhoven, Netherlands. - - 2013
Simulators have been proven to equip trainee surgeons with better skills than the traditional, standard approach to skill development. The purpose of this study was to develop a low-fidelity, low-cost, reusable and portable simulation device, which could provide training in nearly the full range of mitral valve surgery techniques, in ...
Rabbah Jean-Pierre JP Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 313 Ferst Drive, Atlanta, GA 30332-0535, - - 2013
Numerical models of the mitral valve have been used to elucidate mitral valve function and mechanics. These models have evolved from simple two-dimensional approximations to complex three-dimensional fully coupled fluid structure interaction models. However, to date these models lack direct one-to-one experimental validation. As computational solvers vary considerably, experimental benchmark ...
Young Melissa - - 2012
In certain populations, open heart surgery to replace a diseased mitral valve is not an option, leaving percutaneous delivery a viable alternative. However, a surgical transcatheter based delivery of a metallic support frame incorporating a tissue derived valve puts considerable constraints on device specifications. Expansion to a large diameter from ...
Godard B G - - 2012
In the past few years, the small spotted dogfish has become the primary model for analyses of early development in chondrichthyans. Its phylogenetic position makes it an ideal outgroup to reconstruct the ancestral gnathostome state by comparisons with established vertebrate model organisms. It is also a suitable model to address ...
Vandenberg Laura N - - 2013
Consistent left-right (LR) patterning of the heart and viscera is a crucial part of normal embryogenesis. Because errors of laterality form a common class of birth defects, it is important to understand the molecular mechanisms and stage at which LR asymmetry is initiated. Frog embryos are a system uniquely suited ...
Burlina P - - 2012
We describe a method for performing modeling and simulation to predict the closure of the Mitral Valve (MV) using patient specific anatomical information derived from 3D Transesophageal Echocardiography (3D TEE). The ability to predict the MV closure behavior is an important step along the way of developing personalized simulation tools ...
Sprouse C - - 2012
We describe a method for modeling the closure of the Mitral Valve (MV) and to compute realistic strain and stresses in MV tissues. This informs preoperative planning by allowing a surgeon to evaluate various MV repairs options. The modeling method exploits individualized (patient-specific) anatomical structure recovered from real-time 3D echocardiography ...
Lai David - - 2012
With the benefits of automation, sensitivity and precision, microfluidics has enabled complex and otherwise tedious experiments. Lately, lab-on-a-chip (LOC) has proven to be a useful tool for enhancing non-invasive assisted reproductive technology (ART). Non-invasive gamete and embryo assessment has largely been through periodic morpohological assessment using optical microscopy and early ...
Tendeng Christian - - 2012
Good progress has been made in identifying key signaling molecules and explaining how they are used to generate spatial patterns during embryonic development. In contrast, little is known about the control of timing or how cells use time signals in the developing embryo. In this review, I describe how direct ...
Sutter M E - - 2012
Poison center consultations for potential toxic alcohol poisonings are challenging because blood levels are typically not immediately available. The primary objective of this study was to determine whether readily obtainable laboratory values can be used to accurately and rapidly diagnose these poisonings. Over a 15-month period, patients with a history ...
Vandelook Filip - - 2012
• The factors driving the evolution of the relative embryo length in Apiaceae were examined. We tested the hypothesis that seeds with large relative embryo length, because of more rapid germination, are beneficial in dry and open habitats and for short-lived species. We also analyzed to what extent delayed germination ...
Heikkilä A-M - - 2012
In this study, a linear programming model was developed to maximize the gross margin of milk production by determining the optimal use of different reproductive technologies in a dairy herd. The model has the potential to vary the use of conventional artificial insemination, insemination with X-sorted sperm, and the use ...
Gore Aniket V - - 2012
The zebrafish has emerged as an excellent vertebrate model system for studying blood and lymphatic vascular development. The small size, external and rapid development, and optical transparency of zebrafish embryos are some of the advantages the zebrafish model system offers. Multiple well-established techniques have been developed for imaging and functionally ...
Roth Siegfried - - 2012
The generation and interpretation of positional information are key processes in developmental systems. In this issue, Chen et al. report discoveries made in the Drosophila embryo that give new insights into how positional information can be produced by patterning gradients.
Kalinka Alex T - - 2012
There is a remarkable similarity in the appearance of groups of animal species during periods of their embryonic development. This classic observation has long been viewed as an emphatic realization of the principle of common descent. Despite the importance of embryonic conservation as a unifying concept, models seeking to predict ...
Morelli Luis G - - 2012
Computational approaches are breaking new ground in understanding how embryos form. Here, we discuss recent studies that couple precise measurements in the embryo with appropriately matched modeling and computational methods to investigate classic embryonic patterning strategies. We include signaling gradients, activator-inhibitor systems, and coupled oscillators, as well as emerging paradigms ...
Zhang Cindy - - 2012
This study describes a novel rat whole embryo culture (rWEC) teratogenicity assay that applies a simplified experimental design and statistical prediction model resulting in reduced animal requirements and increased throughput with low prediction error for classifying teratogenic potential of compounds. A total 70 compounds (38 teratogens and 32 non-teratogens) were ...
Hardway Heather - - 2012
Many biological systems are inherently noisy, yet demonstrate robustness to perturbations and changes in external influences. Such is the case in the Bicoid-Hunchback (Bcd-Hb) system, which is critical to axis specification in the developing Drosophila embryo. We use this system as motivation to explore the larger problem of how precise ...
Svartz Gabriela V - - 2012
Atrazine (ATR), one of the most widely used herbicides in the world, affects not only target organisms but also the biota in general. Here, the teratogenic and neurotoxic effects of ATR on Rhinella arenarum (South American toad) embryos, and larvae were evaluated by means of standardized bioassays during acute and ...
Kirkegaard Kirstine - - 2012
As elective transfer of a single embryo (eSET) becomes increasingly accepted, the need to improve implantation rates becomes crucial. Selecting the most competent embryo therefore constitutes a major challenge in assisted reproductive technology. Embryo morphology and developmental stage at given time points are closely correlated with developmental competence and assessment ...
Kameda Tomomi - - 2012
Understanding the causes of congenital anomalies is of prime importance to develop management and/or prevention strategies. It is widely accepted that the occurrence of congenital malformations in fetuses and neonates is heavily correlated with maternal genetic makeup and lifestyle. However, very few epidemiologic analyses have been conducted on the embryonic ...
Brown Charmaine Y - - 2012
The amenability of the chick embryo to a variety of manipulations has made it an ideal experimental model organism for over 100 years. The ability to manipulate gene function via in ovo electroporations has further revolutionized its value as an experimental model in the last 15 years. Although in ovo ...
Amiridis G S - - 2012
In modern agriculture, assisted reproductive technologies are being used for out of season oestrus induction, enhancement of reproductive performance and genetic improvement. In addition, they can have substantial contribution in preservation of endangered species or breeds, as well as in eradication programs of various diseases. While their applications are widespread ...
Klingemann Justyna Iwona - - 2012
AIMS: The study provides an in-depth qualitative understanding of the maintenance stage when recovering from alcohol dependence with a focus on the broader social context of change of addictive behaviour. It explores the recovery as a subjective process within the abstinence-oriented Polish treatment system organized on the basis of the ...
Cheng Ya-Ling - - 2012
A new approach to the lipase-catalyzed hydrolytic resolution of (R,S)-azolyl carbamates for obtaining chiral azolyl carbamates and alcohol is described. With (R,S)-1-phenylethyl azolyl carbamates as the model substrates, the best reaction condition of using (R,S)-1-phenylethyl 4-bromopyrazole carbamate (1) as the substrate in water-saturated diisopropyl ether at 45 °C is selected. The ...
Simerly Calvin - - 2012
Nonhuman primates are the closest relatives to humans and therefore our most evolutionary close cousins. While marvelous insights are gleaned from studying rodents and other systems, it is impossible to envision how those mechanistic findings can be responsibly translated to the clinic without the appropriate use of nonhuman primates. Thankfully, ...
Hansen Jason M - - 2012
The founding principles of teratology/developmental toxicology state that a developmental toxicants cause dysmorphogenesis when conceptuses are exposed at a sufficient dosage during a sensitive period of development in a sensitive species. While in vitro approaches in developmental toxicology can provide a means to assess the potency of toxicants, ultimately, the ...
Birdsall William C - - 2012
Objective: The objective of this article is to estimate and validate a logistic model of alcohol-impaired driving using previously ignored alcohol consumption behaviors, other risky behaviors, and demographic characteristics as independent variables. Methods: The determinants of impaired driving are estimated using the US Centers for Disease Control and Prevention's (CDC) ...
Akagi Jin - - 2012
Zebrafish (Danio rerio) has recently emerged as a powerful experimental model in drug discovery and environmental toxicology. Drug discovery screens performed on zebrafish embryos mirror with a high level of accuracy the tests usually performed on mammalian animal models, and fish embryo toxicity assay (FET) is one of the most ...
Toomey Traci L - - 2012
We examined the associations between the density of alcohol establishments and five types of nonviolent crime across urban neighborhoods. Data from the city of Minneapolis, MN, in 2009 were aggregated and analyzed at the neighborhood level. We examined the association between alcohol establishment density and five categories of nonviolent crime: ...
Schmidt Laura A - - 2012
This study examined the potential for biased inference due to endogeneity when using standard approaches for modeling the utilization of alcohol and drug treatment. Results from standard regression analysis were compared with those that controlled for endogeneity using instrumental variables estimation. Comparable models predicted the likelihood of receiving alcohol treatment ...
Holmes John J Section of Public Health, School of Health and Related Research, University of Sheffield, 30 Regent Street, Sheffield S1 4DA, UK. - - 2012
Changes in per capita alcohol consumption are temporally linked to changes in rates of alcohol-related harm. Methodological approaches for analysing this relationship have been suggested, however, the problem of time lags is not well-addressed. This study provides a review of time lag specifications, looking at (a) time to first effect ...
Ljung Aust Mikael - - 2012
Fatal motor vehicle intersection crashes occurring in Norway in the years 2005-2007 were analyzed to identify causation patterns among their underlying contributing factors, and also to assess if the data collection and documentation procedures used by the Norwegian in-depth investigation teams produces the information necessary to do causation pattern analysis. ...
Eng Sereikhuoch - - 2011
The study here presents multiple configurations (i.e., causal recipes) of antecedents associating with heavy drinking using fuzzy-set qualitative comparative analysis (fsQCA). Using national survey data (United States), intermediate solutions of fsQCA analyses yield high consistency and modest coverage in identifying heavy-drinking groups.
Swanson W F - - 2011
Domestic cats are invaluable research models for the study of hereditary diseases that affect both cats and humans. By necessity, most cat models are maintained as living populations; however, semen and embryo cryopreservation could provide a cost-effective alternative for model conservation if viable offspring can be readily produced with assisted ...
Rossow Ingeborg - - 2012
To estimate the effect on violence of small changes in closing hours for on-premise alcohol sales, and to assess whether a possible effect is symmetrical. A quasi-experimental design drawing on data from 18 Norwegian cities that have changed (extended or restricted) the closing hours for on-premise alcohol sales. All changes ...
Mehling Tanja - - 2011
Surfactant based separation processes are a promising alternative to conventional organic solvent processes. A crucial parameter to describe the efficiency of such processes is the partition coefficient between the surfactant aggregates (micelles) and the aqueous bulk phase. In this work several experimental methods to determine these partition coefficients (micellar liquid ...
Ashok Praveen C - - 2011
Standardization and quality monitoring of alcoholic beverages is an important issue in the liquor production industry. Various spectroscopic techniques have proved useful for tackling this problem. An ideal sensing device for alcoholic beverages should be able to detect the quality of alcohol with a small amount of sample at a ...
Murphy Stephen K - - 2011
A method has been developed for the intermolecular hydroacylation of homoallyl alcohols with salicylaldehydes to furnish homoaldol products in 50-98% yields. The method also applies to the hydroacylation of 2-hydroxystyrenes. This work highlights the use of hydroacylation as a unified approach to both aldol and homoaldol products.
Tsai Pui-Jen - - 2011
Spatial analytical techniques and models are often used in epidemiology to identify spatial anomalies (hotspots) in disease regions. These analytical approaches can be used to identify not only the location of such hotspots, but also their spatial patterns. We used spatial autocorrelation methodologies, including Global Moran's I and Local Getis-Ord ...
Carugo Dario - - 2011
A microfluidic based device has been developed for the characterisation of embolisation behaviour with polyvinyl alcohol (PVA) hydrogel beads within a microchannel network with bifurcations which mimic the blood vessel network. Both distal and proximal embolisations were achieved within the PMMA-made microdevice exhibiting comparable embolisation characteristics with those observed in ...
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