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Introduction: Intra-arrest transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) have been introduced in adult patients with cardiac arrest (CA). Whether the diagnostic performance of TTE or TEE is superior during resuscitation is unclear. We conducted a systematic review following PRISMA guidelines.Methods: We searched databases from PubMed, Embase, and Google Scholar and evaluated articles with intra-arrest TTE and TEE in adult patients with non-traumatic CA. Two authors independently screened and selected articles for inclusion; they then dual-extracted study characteristics and target conditions (pericardial effusion, aortic dissection, pulmonary embolism, myocardial infarction, hypovolemia, left ventricular dysfunction, and sonographic cardiac activity). We performed quality assessment using the Quality Assessment of Diagnostic Accuracy Studies Version 2 criteria.Results: A total of 27 studies were included: 14 studies with 2,145 patients assessed TTE; and 16 with 556 patients assessed TEE. A high risk of bias or applicability concerns in at least one domain was present in 20 studies (74%). Both TTE and TEE found positive findings in nearly one-half of the patients. The etiology of CA was identified in 13% (271/2,145), and intervention was performed in 38% (102/271) of patients in the TTE group. In patients who received TEE, the etiology was identified in 43% (239/556), and intervention was performed in 28% (68/239). In the TEE group, a higher incidence regarding the etiology of CA was observed, particularly for those with aortic dissection. However, the outcome of those with aortic dissection in the TEE group was poor.Conclusion: While TEE could identify more causes of CA than TTE, sonographic cardiac activity was reported much more in the TTE group. The impact of TTE and TEE on the return of spontaneous circulation and further survival was still inconclusive in the current dataset.

ABSTRACT In many bacteria, the FtsH protease and its modulators, HflK and HflC, form a large protein complex that contributes to both membrane protein quality control and regulation of the cellular response to environmental stress. Both activities are crucial to the Lyme disease pathogen Borrelia burgdorferi, which depends on membrane functions, such as motility, protein transport, and cell signaling, to respond to rapid changes in its environment. Using an inducible system, we demonstrate that FtsH production is essential for both mouse and tick infectivity and for in vitro growth of B. burgdorferi. FtsH depletion in B. burgdorferi cells resulted in membrane deformation and cell death. Overproduction of the protease did not have any detectable adverse effects on B. burgdorferi growth in vitro, suggesting that excess FtsH does not proteolytically overwhelm its substrates. In contrast, we did not observe any phenotype for cells lacking the protease modulators HflK and HflC (ΔHflK/C), although we examined morphology, growth rate, growth under stress conditions, and the complete mouse-tick infectious cycle. Our results demonstrate that FtsH provides an essential function in the life cycle of the obligate pathogen B. burgdorferi but that HflK and HflC do not detectably affect FtsH function. IMPORTANCE Lyme disease is caused by Borrelia burgdorferi, which is maintained in nature in an infectious cycle alternating between small mammals and Ixodes ticks. B. burgdorferi produces specific membrane proteins to successfully infect and persist in these diverse organisms. We hypothesized that B. burgdorferi has a specific mechanism to ensure that membrane proteins are properly folded and biologically active when needed and removed if improperly folded or dysfunctional. Our experiments demonstrate that FtsH, a protease that fulfills this role in other microorganisms, is essential to B. burgdorferi viability. Cells depleted of FtsH do not survive in laboratory culture medium and cannot colonize mice or ticks, revealing an absolute requirement for this protease. However, the loss of two potential modulators of FtsH activity, HflK and HflC, does not detectably affect B. burgdorferi physiology. Our results provide the groundwork for the identification of FtsH substrates that are critical for the bacterium’s viability.

Quantifications Of uncertainties in soil shear strengths, including undrained shear strength of clay, are essential for geotechnical reliability-based design. In particular, how to reduce the uncertainties in undrained shear strengths based on all available information by correlation is a practical research subject, given the considerable cost of a typical site investigation. Although it is simple to reduce the uncertainties by correlation when the information is one dimensional (or univariate), it is quite challenging to reduce the uncertainties by using multivariate information through multiple correlations. This study proposes a systematic way of achieving multivariate correlations on undrained shear strengths. A set of simplified equations are obtained through Bayesian analysis for the purpose of reducing uncertainties: the inputs to the equations are the results of in situ or laboratory tests and the outputs are the updated mean values and coefficients of variation (c.o.v.s) of the undrained shear strengths. Two case studies are used to demonstrate the consistency of the proposed simplified equations. Results show that uncertainties in undrained shear strengths can be effectively reduced by incorporating multivariate information. Given that reliability-based design can justify more economical design with reduced uncertainties, the proposed equations essentially link the value of more and better tests directly to final design savings. Key words: uncertainty, undrained shear strength, in situ test, correlation. Bayesian analysis. La quantification des incertitudes dans les resistances au cisaillement des sols, incluant la resistance an cisaillement de l'argile, est essentielle pour la conception geotechnique basee sur la fiabilite. Un sujet de recherche pratique concerne les facons de reduire les incertitudes dans les resistances au cisaillement non drainees, basees sur toutes les informations disponibles par correlation, considerant le cout eleve d'une etude typique sur un site. Malgre le fait qu'il soil simple de reduire les incertitudes par correlation lorsque l'information est unidimensionnelle (ou univariee), il est neanmoins plus difficile de reduire les incertitudes a partir de donnees multivariees a correlation multiples. Cette etude propose une methode systematique pour obtenir des correlations multivariees sur des resistances au cisaillement non drainees. Une serie d'equations simplifies sont obtenues a 1'aide d'une analyse Bayesienne dans le but de reduire les incertitudes : les resultats d'essais in situ ou en laboratoire servent d'intrants pour les equations, les sortants etant les moyennes des valeurs et des coefficients de variation (c.o.v.s) pour les resistances au cisaillement non drainees. Deux etudes de cas sont presentees afin de demontrer la coherence des equations simplifies proposees. Les resultats montrent que les incertitudes dans les resistances au cisaillement non drainees peuvent effeclivement etre reduites en integrant des informations multivariees. Etant donne que la conception basee sur la fiabilite pent justifier des conceptions plus economiques avec des incertitudes reduites, les equations proposees font le lien direct entre la valeur d'essais meilleurs el plus nombreux et les economies a la conception finale. Mots-cles : incertitude, resistance au cisaillement non drainee, essai in situ, correlation, analyse Bayesienne. [Traduit par la Redaction], Introduction Uncertainties are commonly encountered in geotechnical engineering. Possible sources of these uncertainties may include inherent variabilities, measurement errors, modeling (or transformation) uncertainties, etc. More economical geotechnical designs can be [...]

The most typical and catastrophic car-motorcycle crash occurs when a car manoeuvres into the path of an approaching motorcycle at an intersection, which involves a car driver violating motorcycle's right of way (ROW). In Taiwan, however, motorcyclists are frequently the ROW violator--they are observed to frequently infringe upon the ROW of oncoming vehicles at intersections. Such a ROW crash in which a left-turn motorcyclist crosses in front of approaching traffic appears to be a safety problem in terms of its frequency and accident consequence. Using the National Taiwan Crash Database, the present study estimates a logistic regression model to predict the likelihood of an approach-turn motorcycle-turning crash (relative to a car-turning crash). Results indicate that given a ROW crash where the rider was female, old, drunk, unlicensed, riding a moped, and on a NBU roadway, the likelihood of a motorcycle-turning crash tends to increase. Our study contributes to the existing motorcycle safety research by reporting the determinants of the unique crashes in which the motorcyclist is the ROW violator., 1. Introduction Past studies [1-5] have identified motorcycle right-of-way (ROW) crash as the most typical and catastrophic car-motorcycle crash that occurs at an intersection. The crash type involves a car [...]

This paper presents a newly developed simulation-based approach for Bayesian model updating, model class selection, and model averaging called the transitional Markov chain Monte Carlo (TMCMC) approach. The idea behind TMCMC is to avoid the problem of sampling from difficult target probability density functions (PDFs) but sampling from a series of intermediate PDFs that converge to the target PDF and are easier to sample. The TMCMC approach is motivated by the adaptive Metropolis--Hastings method developed by Beck and Au in 2002 and is based on Markov chain Monte Carlo. It is shown that TMCMC is able to draw samples from some difficult PDFs (e.g., multimodal PDFs, very peaked PDFs, and PDFs with flat manifold). The TMCMC approach can also estimate evidence of the chosen probabilistic model class conditioning on the measured data, a key component for Bayesian model class selection and model averaging. Three examples are used to demonstrate the effectiveness of the TMCMC approach in Bayesian model updating, model class selection, and model averaging. DOI: 10.1061/(ASCE)0733-9399(2007)133:7(816) CE Database subject headings: Bayesian analysis; Simulation; Markov chains; Monte Carlo method.