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https://www.readbyqxmd.com/read/28218673/a-high-performance-piezoelectric-sensor-for-dynamic-force-monitoring-of-landslide
#1
Ming Li, Wei Cheng, Jiangpan Chen, Ruili Xie, Xiongfei Li
Due to the increasing influence of human engineering activities, it is important to monitor the transient disturbance during the evolution process of landslide. For this purpose, a high-performance piezoelectric sensor is presented in this paper. To adapt the high static and dynamic stress environment in slope engineering, two key techniques, namely, the self-structure pressure distribution method (SSPDM) and the capacitive circuit voltage distribution method (CCVDM) are employed in the design of the sensor...
February 17, 2017: Sensors
https://www.readbyqxmd.com/read/28218352/concomitant-pulsatile-and-continuous-flow-vad-in-biventricular-and-univentricular-physiology-a-comparison-study-with-a-numerical-model
#2
Arianna Di Molfetta, Gianfranco Ferrari, Roberta Iacobelli, Sergio Filippelli, Paolo Guccione, Libera Fresiello, Gianluigi Perri, Antonio Amodeo
INTRODUCTION: To develop and test a lumped parameter model to simulate and compare the effects of the simultaneous use of continuous flow (CF) and pulsatile flow (PF) ventricular assist devices (VADs) to assist biventricular circulation vs. single ventricle circulation in pediatrics. METHODS: Baseline data of 5 patients with biventricular circulation eligible for LVAD and of 5 patients with Fontan physiology were retrospectively collected and used to simulate patient baselines...
February 11, 2017: International Journal of Artificial Organs
https://www.readbyqxmd.com/read/28213997/echocardiographic-correlates-are-associated-with-in-hospital-mortality-in-trauma-and-burn-patients
#3
Duraid Younan, Russell Griffin, Donald Reiff, Jeffrey Richey, Eric Schinnerer, Jean-Francois Pittet, Ahmed Zaky
BACKGROUND: The role of echocardiographic indices of preload and contractility in predicting outcomes is unknown. We report the association of end diastolic area (EDA) and fractional area of change (FAC) with mortality in a cohort of trauma and burn patients. METHODS: Data on 86 patients admitted to a tertiary care center between July 2013 and July 2015 were reviewed. The association between abnormal EDA and FAC and adverse clinical outcomes was tested using exact logistic regression analysis...
February 9, 2017: American Journal of Surgery
https://www.readbyqxmd.com/read/28213737/associations-among-left-ventricular-systolic-function-tachycardia-and-cardiac-preload-in-septic-patients
#4
Michael J Lanspa, Sajid Shahul, Andrew Hersh, Emily L Wilson, Troy D Olsen, Eliotte L Hirshberg, Colin K Grissom, Samuel M Brown
BACKGROUND: In sepsis, tachycardia may indicate low preload, adrenergic stimulation, or both. Adrenergic overstimulation is associated with septic cardiomyopathy. We sought to determine whether tachycardia was associated with left ventricular longitudinal strain, a measure of cardiac dysfunction. We hypothesized an association would primarily exist in patients with high preload. METHODS: We prospectively observed septic patients admitted to three study ICUs, who underwent early transthoracic echocardiography...
December 2017: Annals of Intensive Care
https://www.readbyqxmd.com/read/28212954/evaluation-of-copd-treatments-a-multicriteria-decision-analysis-of-aclidinium-and-tiotropium-in-the-united-states
#5
Kevin Marsh, Erica Zaiser, Panagiotis Orfanos, Suzanne Salverda, Teresa Wilcox, Shawn Sun, Shailja Dixit
BACKGROUND: Comparisons of the use of aclidinium bromide and tiotropium bromide for the treatment of chronic obstructive pulmonary disease often concentrate on key end points (exacerbations) at the expense of other benefits and risks. Multicriteria decision analysis (MCDA) can help overcome this by using stakeholder preferences to combine multiple end points into an overall value estimate. OBJECTIVES: To evaluate the use of aclidinium bromide twice daily via Pressair™ (AstraZeneca Pharmaceuticals LP, Wilmington, DE) and of tiotropium once daily via HandiHaler(®) (Boehringer Ingelheim Pharmaceuticals, Inc...
January 2017: Value in Health: the Journal of the International Society for Pharmacoeconomics and Outcomes Research
https://www.readbyqxmd.com/read/28212401/preload-based-starling-like-control-of-rotary-blood-pumps-an-in-vitro-evaluation
#6
Mahdi Mansouri, Shaun D Gregory, Robert F Salamonsen, Nigel H Lovell, Michael C Stevens, Jo P Pauls, Rini Akmeliawati, Einly Lim
Due to a shortage of donor hearts, rotary left ventricular assist devices (LVADs) are used to provide mechanical circulatory support. To address the preload insensitivity of the constant speed controller (CSC) used in conventional LVADs, we developed a preload-based Starling-like controller (SLC). The SLC emulates the Starling law of the heart to maintain mean pump flow ([Formula: see text]) with respect to mean left ventricular end diastolic pressure (PLVEDm) as the feedback signal. The SLC and CSC were compared using a mock circulation loop to assess their capacity to increase cardiac output during mild exercise while avoiding ventricular suction (marked by a negative PLVEDm) and maintaining circulatory stability during blood loss and severe reductions in left ventricular contractility (LVC)...
2017: PloS One
https://www.readbyqxmd.com/read/28210935/the-effect-of-fluid-resuscitation-on-the-effective-circulating-volume-in-patients-undergoing-liver-surgery-a-post-hoc-analysis-of-a-randomized-controlled-trial
#7
Jaap Jan Vos, A F Kalmar, H G D Hendriks, J Bakker, T W L Scheeren
To assess the significance of an analogue of the mean systemic filling pressure (Pmsa) and its derived variables, in providing a physiology based discrimination between responders and non-responders to fluid resuscitation during liver surgery. A post-hoc analysis of data from 30 patients undergoing major hepatic surgery was performed. Patients received 15 ml kg(-1) fluid in 30 min. Fluid responsiveness (FR) was defined as an increase of 20% or greater in cardiac index, measured by FloTrac-Vigileo(®). Dynamic preload variables (pulse pressure variation and stroke volume variation: PPV, SVV) were recorded additionally...
February 16, 2017: Journal of Clinical Monitoring and Computing
https://www.readbyqxmd.com/read/28210644/axial-plane-biomechanical-evaluation-of-2-suspensory-cortical-button-fixation-constructs-for-acromioclavicular-joint-reconstruction
#8
REVIEW
Steven Struhl, Theodore S Wolfson, Frederick Kummer
BACKGROUND: Although numerous suture-button fixation techniques for acromioclavicular (AC) joint reconstruction have been validated with biomechanical testing in the superior direction, clinical reports continue to demonstrate high rates of construct slippage and breakage. PURPOSE: To compare the stability of a novel closed-loop double Endobutton construct with a commercially available cortical button system in both the axial and superior directions. STUDY DESIGN: Controlled laboratory study...
December 2016: Orthopaedic Journal of Sports Medicine
https://www.readbyqxmd.com/read/28207430/evaluation-of-augmented-pulse-pressure-variation-using-the-valsalva-manoeuvre-as-a-predictor-of-fluid-responsiveness-under-open-chest-conditions-a-prospective-observational-study
#9
Jeong Jin Min, Tae Kyong Kim, Jong-Hwan Lee, Jiyeon Park, Hyun Sung Cho, Wook Sung Kim, Young Tak Lee
BACKGROUND: Pulse pressure variation (PPV) is a well known dynamic preload indicator of fluid responsiveness. However, its usefulness in open-chest conditions remains controversial. OBJECTIVE: We evaluated whether augmented PPV during a Valsalva manoeuvre can predict fluid responsiveness after sternotomy. DESIGN: A prospective, observational study. SETTING: Single-centre trial, study period from October 2014 to June 2015...
February 15, 2017: European Journal of Anaesthesiology
https://www.readbyqxmd.com/read/28202132/comparison-of-platelet-reactivity-in-black-versus-white-patients-with-acute-coronary-syndromes-after-treatment-with-ticagrelor
#10
Michael A Gaglia, Michael J Lipinski, Thibault Lhermusier, Arie Steinvil, Sarkis Kiramijyan, Shreejana Pokharel, Rebecca Torguson, Dominick J Angiolillo, Lars Wallentin, Robert F Storey, Ron Waksman
Ticagrelor, a potent platelet inhibitor, has primarily been studied in white patients. Platelet reactivity among black patients with acute coronary syndrome (ACS) on ticagrelor, however, is unknown. Our objective was to compare platelet reactivity in black versus white patients with ACS treated with ticagrelor. We conducted a prospective, pharmacodynamic study of 29 black patients with ACS treated with ticagrelor. Platelet reactivity was assessed at 1, 4, and 8 hours after a loading dose of ticagrelor 180 mg and at 30 days on a maintenance dose of ticagrelor 90 mg twice daily...
January 25, 2017: American Journal of Cardiology
https://www.readbyqxmd.com/read/28196632/procedure-selection-and-patient-positioning-influence-spine-kinematics-during-high-velocity-low-amplitude-spinal-manipulation-applied-to-the-low-back
#11
Spencer Bell, Kevin D'Angelo, Gregory N Kawchuk, John J Triano, Samuel J Howarth
OBJECTIVES: This investigation compared indirect 3-dimensional angular kinematics (position, velocity, and acceleration) of the lumbar spine for 2 different high-velocity, low-amplitude (HVLA) spinal manipulation procedures (lumbar spinous pull or push), and altered initial patient lower limb posture. METHODS: Twenty-four participants underwent 6 HVLA procedures directed toward the presumed L4 vertebra, reflecting each combination of 2 variants of a spinal manipulation application technique (spinous pull and push) and 3 initial hip flexion angles (0°, 45°, and 90°) applied using a right lateral recumbent patient position...
February 10, 2017: Journal of Manipulative and Physiological Therapeutics
https://www.readbyqxmd.com/read/28195341/left-ventricular-systolic-function-is-associated-to-sympathetic-nervous-activity-and-markers-of-inflammation-in-cirrhosis
#12
Raquel Yotti, Cristina Ripoll, Yolanda Benito, Maria Vega Catalina, Jaime Elízaga, Diego Rincón, Francisco Fernández-Avilés, Javier Bermejo, Rafael Bañares
: An accurate evaluation of cardiac function in patients with cirrhosis remains a challenge. We used robust echocardiographic indices to characterize LV systolic function and its relationship to activation of the sympathetic nervous system (SNS) and inflammation in 59 patients cirrhosis and 59 age-matched controls. Aditionally, in eleven patients we withdrew betablockers and diuretics and used phenylephrine and albumin infusion to evaluate the response to acute afterload and preload changes (interventional substudy)...
February 13, 2017: Hepatology: Official Journal of the American Association for the Study of Liver Diseases
https://www.readbyqxmd.com/read/28193800/cardiovascular-and-ventilatory-consequences-of-laparoscopic-surgery
#13
Tamara M Atkinson, George D Giraud, Brandon M Togioka, Daniel B Jones, Joaquin E Cigarroa
Although laparoscopic surgery accounts for >2 million surgical procedures every year, the current preoperative risk scores and guidelines do not adequately assess the risks of laparoscopy. In general, laparoscopic procedures have a lower risk of morbidity and mortality compared with operations requiring a midline laparotomy. During laparoscopic surgery, carbon dioxide insufflation may produce significant hemodynamic and ventilatory consequences such as increased intraabdominal pressure and hypercarbia. Hemodynamic insults secondary to increased intraabdominal pressure include increased afterload and preload and decreased cardiac output, whereas ventilatory consequences include increased airway pressures, hypercarbia, and decreased pulmonary compliance...
February 14, 2017: Circulation
https://www.readbyqxmd.com/read/28191976/preloading-with-unlabeled-ca19-9-targeted-human-monoclonal-antibody-leads-to-improved-pet-imaging-with-89zr%C3%A2-5b1
#14
Jacob Lee Houghton, Dalya Abdel-Atti, Wolfgang W Scholz, Jason S Lewis
CA19.9 is one of the most commonly occurring and highest density antigens in >90% of pancreatic cancers, making it an excellent target for monoclonal antibody (mAb)-based imaging and therapy applications. Preloading of unlabeled antibodies to enhance targeting of a radiolabeled mAb has been previously described both for imaging and radioimmunotherapy studies for other targets. We investigated the effect of preloading with the unmodified anti-CA19.9 antibody 5B1 on the uptake and contrast of the PET tracer 89Zr-5B1 in subcutaneous and orthotopic murine models of pancreatic cancer utilizing Capan-2 xenografts, known to both expresses CA19...
February 13, 2017: Molecular Pharmaceutics
https://www.readbyqxmd.com/read/28186765/complete-decomposition-of-li2co3-in-li-o2-batteries-using-ir-b4c-as-non-carbon-based-oxygen-electrode
#15
Shidong Song, Wu Xu, Jianming Zheng, Langli Luo, Mark H Engelhard, Mark E Bowden, Bin Liu, Chongmin Wang, Ji-Guang Zhang
Instability of carbon based oxygen electrode and incomplete decomposition of Li2CO3 during charge process are critical barriers for rechargeable Li-O2 batteries. Here we report complete decomposition of Li2CO3 in Li-O2 batteries using ultrafine-iridium-decorated boron carbide (Ir/B4C) nanocomposite as a non-carbon based oxygen electrode. The systematic investigation on charging the Li2CO3 preloaded Ir/B4C electrode in an ether-based electrolyte demonstrates that Ir/B4C electrode can decompose Li2CO3 with an efficiency close to 100% at below 4...
February 10, 2017: Nano Letters
https://www.readbyqxmd.com/read/28183565/minimum-effective-fluid-volume-of-colloid-to-prevent-hypotension-during-caesarean-section-under-spinal-anesthesia-using-a-prophylactic-phenylephrine-infusion-an-up-down-sequential-allocation-study
#16
Christian Loubert, Pierre-Olivier Gagnon, Roshan Fernando
STUDY OBJECTIVE: The aim of this study was to de termine the minimum effective fluid volume (MEFV) of hydroxyethyl starch 130/0.4 (HES) infused in a preload fashion which would prevent hypotension in 50% of parturients undergoing caesarean section. A secondary objective was to measure the hemodynamic effect of fluid loading on the subjects. DESIGN: This is a prospective, double-blinded, dose-finding study using an up-down sequential allocation design. SETTING: In the operating room...
February 2017: Journal of Clinical Anesthesia
https://www.readbyqxmd.com/read/28182575/response-of-a-physiological-controller-for-ventricular-assist-devices-during-acute-patho-physiological-events-an-in-vitro-study
#17
Anastasios Petrou, Panagiotis Pergantis, Gregor Ochsner, Raffael Amacher, Thomas Krabatsch, Volkmar Falk, Mirko Meboldt, Marianne Schmid Daners
The current paper analyzes the performance of a physiological controller for turbodynamic ventricular assist devices (tVADs) during acute patho-physiological events. The numerical model of the human blood circulation implemented on our hybrid mock circulation was extended in order to simulate the Valsalva maneuver (VM) and premature ventricular contractions (PVCs). The performance of an end-diastolic volume (EDV)-based physiological controller for VADs, named preload responsive speed (PRS) controller was evaluated under VM and PVCs...
February 9, 2017: Biomedizinische Technik. Biomedical Engineering
https://www.readbyqxmd.com/read/28181931/avoiding-complications-associated-with-preloaded-ultrathin-descemet-stripping-automated-endothelial-keratoplasty
#18
Mohit Parekh, Alessandro Ruzza, Bernhard Steger, Colin E Willoughby, Stefano Ferrari, Diego Ponzin, Stephen B Kaye, Vito Romano
No abstract text is available yet for this article.
February 8, 2017: Cornea
https://www.readbyqxmd.com/read/28181908/effects-of-endogenous-cardioprotective-mechanisms-on-ischemia-reperfusion-injury
#19
Marcin Kunecki, Wojciech Płazak, Piotr Podolec, Krzysztof S Gołba
Ischemic heart disease have been remarked as a leading cause of morbidity and mortality in adults. Early restoration of cardiac perfusion is necessary to restore perfusion of ischemic heart muscle. Effective revascularization reduce mortality by limiting myocardial necrosis at the acute phase of the cardiac infarction. However, reperfusion may induce a cascade of pathophysiological reactions causing the increase of the infarct area of the myocardium This phenomenon known as ischemia-reperfusion injury is responsible for up to 50% of the final infarct size...
January 10, 2017: Postȩpy Higieny i Medycyny Doświadczalnej
https://www.readbyqxmd.com/read/28173978/the-effects-of-tibia-profile-distraction-angle-and-knee-load-on-wedge-instability-and-hinge-fracture-a-finite-element-study
#20
Pei-Wei Weng, Chia-Hsien Chen, Chu-An Luo, Jui-Sheng Sun, Yang-Hwei Tsuang, Cheng-Kung Cheng, Shang-Chih Lin
Several plate systems for high tibial osteotomy (HTO) have been developed to stabilize the opening wedge of an osteotomized tibia. Among them, the TomoFix system, having a quasi-straight and T-shaped design, has been widely adopted in the literature. However, this system is implemented by inserting a lag (i.e., cortical) screw through the proximal combi-hole, to deform the plate and pull the distal tibia toward the plate. This process potentially induces plate springback and creates an elastic preload on the osteotomized tibia, especially at the lateral hinge of the distracted wedge...
February 4, 2017: Medical Engineering & Physics
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