Search Results
Results 1 - 50 of 2457
1 2 3 4 5 6 7 8 9 10 >
Penny A M AM School of GeoSciences, University of Edinburgh, West Mains Road, Edinburgh EH9 3JW, UK. - - 2014
Reef-building in metazoans represents an important ecological innovation whereby individuals collectively enhance feeding efficiency and gain protection from competitors and predation. The appearance of metazoan reefs in the fossil record therefore indicates an adaptive response to complex ecological pressures. In the Nama Group, Namibia, we found evidence of reef-building by ...
ProcheĊŸ Serban S Discipline of Geography, University of KwaZulu-Natal, Westville Campus, PO Box X54001, Durban 4000, South Africa Environmental and Life Sciences Programme, Universiti Brunei Darussalam, Jalan Tungku Link 1410, Brunei Darussalam - - 2014
We use dated phylogenetic trees for tetrapod vertebrates to identify lineages that shifted between terrestrial and aquatic ecosystems in terms of feeding or development, and to assess the timing of such events. Both stem and crown lineage ages indicate a peak in transition events in correspondence with the K-Pg mass ...
Gritti Fabrice F Department of Chemistry, University of Tennessee, Knoxville, TN 37996-1600, - - 2014
The effect of the pressure on the dispersion of a low molecular weight compound along 0.508 and 1.016mm i.d. × 50cm long open circular tubes was investigated theoretically and experimentally. The theoretical predictions were based on the early models of dispersion derived by Aris and Taylor (1953) and on the ...
Lorente Leonardo - - 2014
The use of a system for continuous control of endotracheal tube cuff pressure reduced the incidence of ventilator-associated pneumonia (VAP) in one randomized controlled trial (RCT) with 112 patients but not in another RCT with 142 patients. In several guidelines on the prevention of VAP, the use of a system ...
Revel G M GM DIISM, Università Politecnica delle Marche, Ancona, - - 2014
The present paper proposes a new characterization technique for air-coupled ultrasound probes. The technique is based on a shock tube to generate a controlled pressure wave to calibrate transducers within their operating frequency range. The aim is to generate a high frequency pressure wave (at least up to 200kHz) with ...
Wang Jidong J Beijing Engineering Research Center for BioNanotechnology & Key Lab for Biological Effects of Nanomaterials and Nanosafety, National Center for NanoScience and Technology, Beijing, 100190, China. xingyujiang@nanoctr.cn - - 2014
This report describes a straightforward but robust tubing method for connecting polydimethylsiloxane (PDMS) microfluidic devices to external equipment. The interconnection is irreversible and can sustain a pressure of up to 4.5 MPa that is characterized experimentally and theoretically. To demonstrate applications of this high-pressure tubing technique, we fabricate a semicircular ...
Grabenbauer Markus M Institute for Anatomy and Cell Biology Germany, University of Heidelberg, Heidelberg, - - 2014
High-pressure freeze fixation is the method of choice to arrest instantly all dynamic and physiological processes inside cells, tissues, and small organisms. Embedded in vitreous ice, such samples can be further processed by freeze substitution or directly analyzed in their fully hydrated state by cryo-electron microscopy of vitreous sections (CEMOVIS) ...
Papazova Diana A DA Department of Nephrology & Hypertension, University Medical Center Utrecht, Utrecht, The - - 2014
While the presence of oxidative stress in chronic kidney disease (CKD) is well established, its relation to hypertensive renal hemodynamics remains unclear. We hypothesized that once CKD is established blood pressure and renal vascular resistance (RVR) no longer depend on reactive oxygen species. CKD was induced by bilateral ablation of ...
Aquila Marco M Department of Bioscience, University of Milan, Milan, - - 2014
Whole-cell recording is the most widely used configuration of the patch recording technique, mainly because it allows to manipulate the intracellular environment while recording membrane current. However, the patch pipette tapered shank and the small tip opening give high access resistances and preclude efficient exchange between pipette solution and cell ...
Ikeda C M CM Department of Mechanical Engineering , University of Maryland , College Park, MD 20742, - - 2013
The implosion of cylindrical shell structures in a high-pressure water environment is studied experimentally. The shell structures are made from thin-walled aluminium and brass tubes with circular cross sections and internal clearance-fit aluminium end caps. The structures are filled with air at atmospheric pressure. The implosions are created in a ...
Lourenço Isabela Scali - - 2013
To compare pressure-support ventilation with spontaneous breathing through a T-tube for interrupting invasive mechanical ventilation in patients undergoing cardiac surgery with cardiopulmonary bypass. Adults of both genders were randomly allocated to 30 minutes of either pressure-support ventilation or spontaneous ventilation with "T-tube" before extubation. Manovacuometry, ventilometry and clinical evaluation were ...
Adi Na - - 2013
The study objective was to evaluate endotracheal tubes (ETT) from extubated adult patients and compare them to new, unused, size-matched control tubes for changes in inspiratory resistance (Rinsp) and peak inspiratory pressure (PIP) before and immediately after suctioning with the Airway Medix Closed Suction System (AMCSS) (Biovo Technologies, 2013 Tel ...
Nichols Michael D MD Department of Biomedical Engineering, Center for Biomolecular and Tissue Engineering, Duke University, Durham, North Carolina, - - 2013
In this study, the coagulation-induced resistance to flow in small-diameter nonpermeable Tygon tubes and permeable expanded polytetrafluoroethylene (ePTFE) vascular grafts was characterized by measuring the upstream pressure needed to purge the coagulum from the tube lumen. This purging pressure was monitored using a closed system that compressed the contents of ...
Kanotra Sohit P - - 2013
Objective: To assess the risk of aspiration using a novel valve circuit that dynamically modulates endotracheal tube cuff pressure during the ventilatory cycle using bench and live animal models. Study Design: Animal model Methods: The bench model consisted of a cuffed endotracheal tube inserted into an artificial trachea. Leakage of ...
Patricia King Jie Hung - - 2013
Coptotermes curvignathus Holmgren is capable of feeding on living tree. This ability is attributed to their effective digestive system that is furnished by the termite's own cellulolytic enzymes and cooperative enzymes produced by their gut microbes. In this study, the identity of an array of diverse microbes residing in the ...
Matsuda Yu - - 2013
The pressure-sensitive paint technique based on the heterodyne method was proposed for the precise pressure measurement of unsteady flow fields. This measurement is realized by detecting the beat signal that results from interference between a modulating illumination light source and a pressure fluctuation. The beat signal is captured by a ...
Plotnikow Gustavo A GA Respiratory Care Services, Clínica Basilea, Argentina ; Intensive Care Unit, Sanatorio Anchorena, Buenos Aires, - - 2013
Most of the studies referring cuff tubes' issues were conducted on intubated patients. Not much is known about the cuff pressure performance in chronically tracheostomized patients disconnected from mechanical ventilation. To evaluate cuff pressure (CP) variation in tracheostomized, spontaneously breathing patients in a weaning rehabilitation center. Experimental setup to test ...
White-Traut Rosemary - - 2013
The Medoff-Cooper Nutritive Sucking Apparatus (M-CNSA) has been used to objectively measure sucking maturation in preterm infants. The M-CNSA is able to accurately detect sucking pressures less than 20mmHg, however lower pressure thresholds have not previously been used in research. To determine if differences are observed in the number of ...
Agatz Annika - - 2013
A population experiment with Daphnia magna tested the hypothesis that short-term feeding inhibition provokes a shift in population structure that will vary with conspecific pressure (e.g., pressure occurring from individuals of the same species due to competition for food and space) and increases population sensitivity to a xenobiotic exposure due ...
Gu Dongfeng - - 2013
Blood pressure responses to dietary sodium and potassium interventions vary among individuals. We studied the long-term reproducibility of blood pressure responses to dietary sodium and potassium intake. We repeated the dietary sodium and potassium interventions among 487 Chinese adults 4.5 years after the original dietary intervention. The identical dietary intervention ...
Tsai Chen-Chih - - 2013
We developed a novel technique enabling determination of the permeability of electrospun yarns composed of hundreds of fibers. Analyzing the wicking kinetics in a yarn-in-a-tube composite conduit it was found that the kinetic is very specific. The liquid was pulled by the capillary pressure associated with the meniscus in the ...
Lau A Cw - - 2013
OBJECTIVES. To compare three endotracheal tubes for leakage across the cuff (microaspiration) under a comprehensive set of simulated clinical situations. These were the Mallinckrodt TaperGuard (Covidien, US) with a tapered polyvinyl chloride cuff; the KimVent Microcuff (Kimberly-Clark Health Care, US) with a cylindrical polyurethane cuff, and a conventional Portex (Smiths ...
Enflo Laura - - 2013
Resonance tube phonation in water (RTPW) or in air is a voice therapy method successfully used for treatment of several voice pathologies. Its effect on the voice has not been thoroughly studied. This investigation analyzes the effects of RTPW on collision and phonation threshold pressures (CTP and PTP), the lowest ...
Sashida Yasunori - - 2013
Abstract Management of a chest tube, especially when lasting for a long period, becomes difficult. The orifice of thoracostomy where a tube is inserted is maintained sterile usually with water-tight sutures. The longer and tighter the sutures are placed, the more severely skin becomes sore by pressure. Recently not only ...
Rosado-Reyes Claudette M - - 2013
Rate coefficients for the dehydration of isobutanol have been determined experimentally from comparative rate single pulse shock tube measurements and calculated via multi-structural transition state theory (MS-TST). They are represented by the Arrhenius expression, k(isobutanol → isobutene + H2O)experimental = 7.2×1013 exp(-35 300 K/T) s-1 The theoretical work leads to ...
Barrett Elizabeth J - - 2013
OBJECTIVE: To determine the effect of gastric distension on intraabdominal pressures (IAP) measured directly from the intraperitoneal space. DESIGN: Prospective, experimental study. SETTING: A university-based equine research facility. ANIMALS: Ten healthy adult horses, 5 males and 5 females. INTERVENTIONS: Intraabdominal pressures were measured through an intraperitoneal cannula zeroed at a ...
Matkowska Dobrochna - - 2013
Densities of pure 1-butyl-3-methylimidazolium methylsulfate, [C4mim][MeSO4], and its mixtures with methanol have been measured. Measurements were made with an accuracy of ±0.2 kg·m(-3), using a vibrating-tube densimeter, over the temperature and pressure ranges (283.15-333.15) K and (0.1-35) MPa, respectively. The experimental densities for the pure ionic liquid and alcohol have been correlated by ...
Nichols Michael D - - 2013
In this study, the coagulation-induced resistance to flow in small-diameter nonpermeable Tygon tubes and permeable expanded polytetrafluoroethylene (ePTFE) vascular grafts was characterized by measuring the upstream pressure needed to purge the coagulum from the tube lumen. This purging pressure was monitored using a closed system that compressed the contents of ...
Gopalakrishnan Senthil - - 2013
OBJECTIVES: Various devices have been used to measure the intracuff pressure (CP) of an endotracheal tube at the time of inflation; however, no device has found widespread acceptance for the continuous monitoring of CP. We devised a simple method to continuously measure the CP using an invasive pressure monitoring setup ...
Steele Catriona M - - 2013
BACKGROUND: It is estimated that approximately 50% of stroke survivors will experience swallowing difficulty, or dysphagia. The associated sequelae of dysphagia include dehydration, malnutrition, and aspiration pneumonia, all of which have can have serious medical consequences. To improve swallowing safety and efficiency, alternative nutritional intake methods (for example, a feeding ...
Jumah Miriam J - - 2013
Impaired Eustachian tube function can limit one's fitness to dive. This study investigated the effect of minimally invasive laser Eustachian tuboplasty (laser tuboplasty) on tube function in divers and its long-term effect on their diving habits. In a prospective surgical trial in nine divers with tubal dysfunction, laser tuboplasty was ...
Nishigawa G - - 2013
OBJECTIVE: A theoretical model, based on fluid dynamics, was developed to measure impression pressure. The purpose of this study was to evaluate the validity of this theoretical model by comparing its theoretical analysis against actual pressure measurements conducted using an impression tray and edentulous oral mucosa analog embedded with pressure ...
Ferrone Giuliano - - 2013
PurposeThe aim of this study was to compare helmet-NIV (non invasive ventilation), in terms of patientventilator interaction and performance, using two different circuits for connection: a double tube circuit (with one inspiratory and one expiratory line) and a standard circuit (an Y piece connected only to one side of the ...
Minonishi Toshiyuki - - 2013
To determine whether the supine-to-prone position change displaced the endotracheal tube (ETT) and, if so, whether the displacement related to this change modified ETT cuff pressure. Prospective study. Operating room of a university hospital. 132 intubated, adult, ASA physical status 1, 2, and 3 patients undergoing lumbar spine surgery. After ...
Gaihede Michael - - 2013
Eustachian tube function is important in pressure regulation of the middle ear. The efficacy or magnitude of pressure equilibration by tube openings should be determined by the gradient between middle ear and ambient pressure, but in theory also the duration of the tube opening may play a role. This study ...
Omeroglu Gokhan - - 2013
The aim of this study is to experimentally investigate the effect of the coiled wire insertions on dynamic instabilities and to compare the results with the smooth tube for forced convection boiling. The experiments were conducted in a circular tube, and water was used as the working fluid. Two different ...
Ruan Sy - - 2013
Previous studies have shown that spontaneous breathing trials (SBT) with a T-tube or low-level pressure support are comparable. However, low-level pressure support may overestimate the ability of a patient to sustain spontaneous breathing, resulting in premature extubation. Understanding factors contributing to different responses by patients to the two SBT methods ...
Roegholt Evelien - - 2013
A T-piece resuscitator (TPR) uses a built-in manometer to set the inflation pressures, but we are not informed what pressures are actually delivered distally. Aim of this study was to measure the proximal and distal pressures under different gas conditions when using a TPR. METHODOLOGYFINDINGS: A test lung was ventilated ...
Mahmoodpoor Ata - - 2013
Because microaspiration of contaminated supraglottic secretions past the endotracheal tube cuff is considered to be central in the pathogenesis of pneumonia, improved design of tracheal tubes with new cuff material and shape have reduced the size and number of folds, which together with the addition of suction ports above the ...
Singh Saurabh - - 2013
Poiseuille's equation describes the relationship between fluid viscosity, pressure, tubing diameter, and flow, yet it is not known if cold organ perfusion systems follow this equation. We investigated these relationships in an ex vivo model and aimed to offer some rationale for equipment selection. Increasing the cannula size from 14 ...
Carter A - - 2012
To reduce the risk of tracheostomy tube blockage, a removable inner tube can be used. However, this will reduce the size of the lumen and will increase airflow resistance and work of breathing. The magnitude of this increase in workload is unknown. We undertook a bench test to measure the ...
Guo Ning - - 2012
We demonstrate an improved low-pressure chemical vapor deposition method to fabricate hexagonal boron nitride (h-BN) domains of a few layers (one-four layers) from ammonia borane by adding a small quartz tube to stabilize the gas flow over the copper substrate and reducing the growing rate of h-BN. The h-BN grows ...
Segami Y - - 2012
Objective:To measure intraoral pressure and perioral movement in infants during breastfeeding (BF) and feeding with experimental teat (ET). The teat has a wide base, firm shaft and a valve at the base, such that milk flows only when the baby provides a hold pressure.Study Design:Twenty healthy term infants, between 1 ...
Stein Howard - - 2012
The electrical activity of the diaphragm (Edi) is measured by a specialized nasogastric/orogastric tube positioned in the esophagus at the level of the crural diaphragm. Neurally adjusted ventilatory assist (NAVA) uses the Edi signal as a neural trigger and intrabreath controller to synchronize mechanical ventilatory breaths with the patient's respiratory ...
Hannezo Edouard - - 2012
We study theoretically the morphologies of biological tubes affected by various pathologies. When epithelial cells grow, the negative tension produced by their division provokes a buckling instability. Several shapes are investigated: varicose, dilated, sinuous, or sausagelike. They are all found in pathologies of tracheal, renal tubes, or arteries. The final ...
Dusick Joshua R - - 2012
The complex pathophysiology of traumatic brain injury (TBI) involves not only the primary mechanical event but also secondary insults such as hypotension, hypoxia, raised intracranial pressure and changes in cerebral blood flow and metabolism. It is increasingly evident that these initial insults as well as transient events and treatments during ...
Campbell Norm - - 2012
Increased blood pressure is a leading risk for premature death and disability. The causes of increased blood pressure are intuitive and well known. However, the fundamental basis and means for improving blood pressure control are highly integrated into our complex societal structure both inside and outside our health system and ...
Fink Ericka L - - 2012
To describe the use and feasibility of cold saline to decrease body temperature in pediatric neurocritical care. Retrospective chart review. Pediatric tertiary care university hospital. Children between 1 wk and 17 yrs of age admitted to the pediatric intensive care unit with acute brain injury and having received intravenous cold ...
De Nicola Luca - - 2011
Whether nephrology management improves over time achievement of blood pressure (BP) goal (<130/<80 mm Hg) in nondialysis CKD is still ill-defined. This historical cohort analysis evaluated the relationship between 1-year nephrology management and BP control in 275 incident CKD patients in an academic renal clinic. Comparative analysis between referral and ...
Asferg Camilla - - 2011
Abstract Objective. The mechanisms by which overweight and physical inactivity lead to hypertension are complex. Leptin, an adipocyte-derived hormone, has been linked with hypertension. We wanted to investigate the relationship between leptin, physical activity and new-onset hypertension. Methods. The study was a prospective cohort study of 744 women and 367 ...
1 2 3 4 5 6 7 8 9 10 >