Maintenance Fluid Therapy: Isotonic Versus Hypotonic Solutions.

PubMed

Hansen, Bernie; Vigani, Alessio

2017-03-01

The goal of maintenance fluid therapy in small animals is to replace normal ongoing losses of water and salts when oral intake is withheld. Hospitalized dogs and cats may have multiple stimuli for antidiuretic hormone release that disrupt normal osmoregulation and predispose to water retention. Severe illness promotes retention of both sodium and water as edema. Commercially available fluids have electrolyte concentrations that are very different from dietary maintenance requirements, and potential consequences include development of hypoosmolality, edema, or both when excesses of water or sodium are administered. Suggestions for tailoring fluid administration toward specific goals are provided. Copyright © 2016 Elsevier Inc. All rights reserved.

Increasing Daily Water Intake and Fluid Adherence in Children Receiving Treatment for Retentive Encopresis

PubMed Central

Hoodin, Flora; Rice, Jennifer; Felt, Barbara T.; Rausch, Joseph R.; Patton, Susana R.

2010-01-01

Objective To examine the efficacy of an enhanced intervention (EI) compared to standard care (SC) in increasing daily water intake and fluid goal adherence in children seeking treatment for retentive encopresis. Methods Changes in beverage intake patterns and fluid adherence were examined by comparing 7-week diet diary data collected during participation in the EI to achieved data for families who had previously completed the SC. Results Compared to children in SC (n = 19), children in the EI (n = 18) demonstrated a significantly greater increase in daily water intake from baseline to the conclusion of treatment ( p ≤ .001), and were four and six times more likely to meet fluid targets in Phases 1 (Weeks 3–4) and 2 (Weeks 5–6) of fluid intervention, respectively (both p ≤ .001). Conclusions Enhanced education and behavioral strategies were efficacious in increasing children’s intake of water and improving fluid adherence. Future research should replicate the findings in a prospective randomized clinical trial to discern their effectiveness. PMID:20439348

[GOAL-DIRECTED FLUID THERAPY IN SEVERE CONCOMITANT TRAUMA].

PubMed

Konkaev, A K; Gurbanova, E I; Mynbaeva, Z N

2015-01-01

We examined 78 patients with severe concomitant injury. Were evaluated the severity of the injury and indices of volumetric haemodynamic monitoring by PICCO. The retrospective comparison group consisted of 50 patients with severe concomitant injury who were treated in the ICU of Trauma Institution during 2009-2011. In patients with severe concomitant injury goal-directed fluid therapy based on PICCO monitoring parameters increasing the volume of infusion on the second and third post-traumatic days by 45% and 24%, respectively (< 0.05). Infusion-related pulmonary complications in the study group patients were not recorded Goal-directed fluid therapy was one of the factors that made it possible to reduce patient's mortality 2.1 times on conditions that severity of the injury and the initial state were similar. Colloid (6% HES 200/0.5) infusion was associated with increases in rate of transient azotemia.

Refractory Hypertension Is not Attributable to Intravascular Fluid Retention as Determined by Intracardiac Volumes.

PubMed

Velasco, Alejandro; Siddiqui, Mohammed; Kreps, Eric; Kolakalapudi, Pavani; Dudenbostel, Tanja; Arora, Garima; Judd, Eric K; Prabhu, Sumanth D; Lloyd, Steven G; Oparil, Suzanne; Calhoun, David A

2018-06-04

Refractory hypertension (RfHTN) is an extreme phenotype of antihypertensive treatment failure defined as lack of blood pressure control with ≥5 medications, including a long-acting thiazide and a mineralocorticoid receptor antagonist. RfHTN is a subgroup of resistant hypertension (RHTN), which is defined as blood pressure >135/85 mm Hg with ≥3 antihypertensive medications, including a diuretic. RHTN is generally attributed to persistent intravascular fluid retention. It is unknown whether alternative mechanisms are operative in RfHTN. Our objective was to determine whether RfHTN is characterized by persistent fluid retention, indexed by greater intracardiac volumes determined by cardiac magnetic resonance when compared with controlled RHTN patients. Consecutive patients evaluated in our institution with RfHTN and controlled RHTN were prospectively enrolled. Exclusion criteria included advanced chronic kidney disease and masked or white coat hypertension. All enrolled patients underwent biochemical testing and cardiac magnetic resonance. The RfHTN group (n=24) was younger (mean age, 51.7±8.9 versus 60.6±11.5 years; P =0.003) and had a greater proportion of women (75.0% versus 43%; P =0.02) compared with the controlled RHTN group (n=30). RfHTN patients had a greater left ventricular mass index (88.3±35.0 versus 54.6±12.5 g/m 2 ; P <0.001), posterior wall thickness (10.1±3.1 versus 7.7±1.5 mm; P =0.001), and septal wall thickness (14.5±3.8 versus 10.0±2.2 mm; P <0.001). There was no difference in B-type natriuretic peptide levels and left atrial or ventricular volumes. Diastolic dysfunction was noted in RfHTN. Our findings demonstrate greater left ventricular hypertrophy without chamber enlargement in RfHTN, suggesting that antihypertensive treatment failure is not attributable to intravascular volume retention. © 2018 American Heart Association, Inc.

Thermocapillary flow with evaporation and condensation and its effect on liquid retention in low-G fluid acquisition devices

NASA Technical Reports Server (NTRS)

Schmidt, George R.

1994-01-01

The steady motion, thermal and free surface behavior of a volatile, wetting liquid in microgravity are studied using scaling and numerical techniques. The objective is to determine whether the thermocapillary and two-phase convection arising from thermodynamic nonequilibrium along the porous surfaces of spacecraft liquid acquisition devices could cause the retention failures observed with liquid hydrogen and heated vapor pressurant. Why these devices seem immune to retention loss when pressurized with heated helium or heated directly through the porous structure was also examined. Results show that highly wetting fluids exhibit large negative and positive dynamic pressure gradients towards the meniscus interline when superheated and subcooled, respectively. With superheating, the pressure variation and recoil force arising from liquid/vapor phase change exert the same influence on surface morphology and promote retention. With subcooling, however, the pressure distribution produces a suction that degrades mechanical equilibrium of the surface. This result indicates that thermocapillary-induced deformation arising from subcooling and condensation is the likely cause for retention loss. In addition, increasing the level of nonequilibrium by reducing accommodation coefficient suppresses deformation and explains why this failure mode does not occur in instances of direct screen heating or pressurization with a heated inert gas.

Hot soup! Correlating the severity of liquid scald burns to fluid and biomedical properties.

PubMed

Loller, Cameron; Buxton, Gavin A; Kerzmann, Tony L

2016-05-01

Burns caused by hot drinks and soups can be both debilitating and costly, especially to pediatric and geriatric patients. This research is aimed at better understanding the fluid properties that can influence the severity of skin burns. We use a standard model which combines heat transfer and biomedical equations to predict burn severity. In particular, experimental data from a physical model serves as the input to our numerical model to determine the severity of scald burns as a consequence of actual fluid flows. This technique enables us to numerically predict the heat transfer from the hot soup into the skin, without the need to numerically estimate the complex fluid mechanics and thermodynamics of the potentially highly viscous and heterogeneous soup. While the temperature of the soup is obviously is the most important fact in determining the degree of burn, we also find that more viscous fluids result in more severe burns, as the slower flowing thicker fluids remain in contact with the skin for longer. Furthermore, other factors can also increase the severity of burn such as a higher initial fluid temperature, a greater fluid thermal conductivity, or a higher thermal capacity of the fluid. Our combined experimental and numerical investigation finds that for average skin properties a very viscous fluid at 100°C, the fluid must be in contact with the skin for around 15-20s to cause second degree burns, and more than 80s to cause a third degree burn. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

Resuscitation With Balanced Fluids Is Associated With Improved Survival in Pediatric Severe Sepsis.

PubMed

Emrath, Elizabeth T; Fortenberry, James D; Travers, Curtis; McCracken, Courtney E; Hebbar, Kiran B

2017-07-01

To evaluate outcomes in patients receiving balanced fluids for resuscitation in pediatric severe sepsis. Observational cohort review of prospectively collected data from a large administrative database. PICUs from 43 children's hospitals. PICU patients diagnosed with severe sepsis. None. We reviewed data from the Pediatric Health Information System database from 2004 to 2012. Children with pediatric severe sepsis receiving balanced fluids for resuscitation in the first 24 and 72 hours of treatment were compared to those receiving unbalanced fluids. Thirty-six thousand nine hundred eight patients met entry criteria for analysis. Two thousand three hundred ninety-eight patients received exclusively balanced fluids at 24 hours and 1,641 at 72 hours. After propensity matching, the 72-hour balanced fluids group had lower mortality (12.5% vs 15.9%; p = 0.007; odds ratio, 0.76; 95% CI, 0.62-0.93), lower prevalence of acute kidney injury (16.0% vs 19.2%; p = 0.028; odds ratio, 0.82; 95% CI, 0.68-0.98), and fewer vasoactive infusion days (3.0 vs 3.3 d; p < 0.001) when compared with the unbalanced fluids group. In this retrospective analysis carried out by propensity matching, exclusive use of balanced fluids in pediatric severe sepsis patients for the first 72 hours of resuscitation was associated with improved survival, decreased prevalence of acute kidney injury, and shorter duration of vasoactive infusions when compared with exclusive use of unbalanced fluids.

Effects of rehydration fluid temperature and composition on body weight retention upon voluntary drinking following exercise-induced dehydration

PubMed Central

Bae, Yoon Jung; Lee, Yong Soo; Kim, Byeong Jo

2012-01-01

The purpose of this study was to determine the effects of beverage temperature and composition on weight retention and fluid balance upon voluntary drinking following exercise induced-dehydration. Eight men who were not acclimated to heat participated in four randomly ordered testing sessions. In each session, the subjects ran on a treadmill in a chamber maintained at 37℃ without being supplied fluids until 2% body weight reduction was reached. After termination of exercise, they recovered for 90 min under ambient air conditions and received one of the following four test beverages: 10℃ water (10W), 10℃ sports drink (10S), 26℃ water (26W), and 26℃ sports drink (26S). They consumed the beverages ad libitum. The volume of beverage consumed and body weight were measured at 30, 60, and 90 min post-recovery. Blood samples were taken before and immediately after exercise as well as at the end of recovery in order to measure plasma parameters and electrolyte concentrations. We found that mean body weight decreased by 1.8-2.0% following exercise. No differences in mean arterial pressure, plasma volume, plasma osmolality, and blood electrolytes were observed among the conditions. Total beverage volumes consumed were 1,164 ± 388, 1,505 ± 614, 948 ± 297, and 1,239 ± 401 ml for 10W, 10S, 26W, and 26S respectively (P > 0.05). Weight retention at the end of recovery from dehydration was highest in 10S (1.3 ± 0.7 kg) compared to 10W (0.4 ± 0.5 kg), 26W (0.4 ± 0.4 kg), and (0.6 ± 0.4 kg) (P < 0.005). Based on these results, carbohydrate/electrolyte-containing beverages at cool temperature were the most favorable for consumption and weight retention compared to plain water and moderate temperature beverages. PMID:22586501

Association of Fluid Accumulation with Clinical Outcomes in Critically Ill Children with Severe Sepsis

PubMed Central

Chen, Jiao; Li, Xiaozhong; Bai, Zhenjiang; Fang, Fang; Hua, Jun; Li, Ying; Pan, Jian; Wang, Jian; Feng, Xing; Li, Yanhong

2016-01-01

Objective To evaluate whether early and acquired daily fluid overload (FO), as well as fluctuations in fluid accumulation, were associated with adverse outcomes in critically ill children with severe sepsis. Methods This study enrolled 202 children in a pediatric intensive care unit (PICU) with severe sepsis. Early fluid overload was defined as ≥5% fluid accumulation occurring in the first 24 hours of PICU admission. The maximum daily fluid accumulation ≥5% occurring during the next 6 days in patients with at least 48 hours of PICU stay was defined as PICU-acquired daily fluid overload. The fluctuation in fluid accumulation was calculated as the difference between the maximum and the minimum daily fluid accumulation obtained during the first 7 days after admission. Results Of the 202 patients, 61 (30.2%) died during PICU stay. Among all patients, 41 (20.3%) experienced early fluid overload, including 9 with a FO ≥10%. Among patients with at least 48 hours of PICU stay (n = 154), 36 (23.4%) developed PICU-acquired daily fluid overload, including 2 with a FO ≥10%. Both early fluid overload (AOR = 1.20; 95% CI 1.08–1.33; P = 0.001; n = 202) and PICU-acquired daily fluid overload (AOR = 5.47 per log increase; 95% CI 1.15–25.96; P = 0.032; n = 154) were independent risk factors associated with mortality after adjusting for age, illness severity, etc. However, fluctuations in fluid accumulation were not associated with mortality after adjustment. Length of PICU stay increased with greater fluctuations in fluid accumulation in all patients with at least 48 hours of PICU stay (FO <5%, 5%-10% vs. ≥10%: 4 [3–8], 7 [4–11] vs. 10 [6–16] days; P <0.001; n = 154) and in survivors (4 [3–8], 7 [5–11] vs. 10 [5–15] days; P <0.001; n = 121). Early fluid overload achieved an area under-the-receiver-operating-characteristic curve of 0.74 (95% CI 0.65–0.82; P <0.001; n = 202) for predicting mortality in patients with severe sepsis, with a sensitivity of 67

Tolvaptan as an alternative treatment for refractory fluid retention associated with sinusoidal obstruction syndrome after allogeneic stem cell transplantation.

PubMed

Yakushijin, Kimikazu; Yamamoto, Katsuya; Kurata, Keiji; Miyata, Yoshiharu; Kakiuchi, Seiji; Tomioka, Hideo; Kawamori-Iwamoto, Yuriko; Inui, Yumiko; Sanada, Yukinari; Okamura, Atsuo; Murayama, Tohru; Matsuoka, Hiroshi; Minami, Hironobu

2013-02-01

Tolvaptan is an oral vasopressin V2-receptor antagonist recognized as effective for fluid retention associated with congestive heart failure and liver cirrhosis. However, there have been no reports concerning clinical experience with tolvaptan for sinusoidal obstruction syndrome (SOS). A 42-year-old male with primarily refractory T-lymphoblastic lymphoma underwent allogeneic peripheral blood stem cell transplantation from an HLA-matched sibling donor. The myeloablative conditioning regimen consisted of busulfan and cyclophosphamide. On day 20, the total bilirubin level was elevated to 2.0 mg/dL, and body weight increased from 76 to 85 kg, allowing a diagnosis of SOS to be made. Treatments with thrombomodulin, furosemide, carperitide, and low-dose dopamine were ineffective. By day 27, the patient's body weight had increased to 90 kg, and he subsequently developed cardiopulmonary failure. Therefore, we administered low-dose tolvaptan for 2 days (3.75 mg on day 27 and 7.5 mg on day 28). Consequently, his ascites and edema were significantly reduced, and body weight returned to 77 kg by day 34. However, he died of lymphoma progression on day 55. Tolvaptan may be an alternative and promising treatment for refractory fluid retention associated with SOS, although it is unclear whether tolvaptan administration leads to improvement in clinical outcome.

Bacteria facilitate prey retention by the pitcher plant Darlingtonia californica

PubMed Central

2016-01-01

Bacteria are hypothesized to provide a variety of beneficial functions to plants. Many carnivorous pitcher plants, for example, rely on bacteria for digestion of captured prey. This bacterial community may also be responsible for the low surface tensions commonly observed in pitcher plant digestive fluids, which might facilitate prey capture. I tested this hypothesis by comparing the physical properties of natural pitcher fluid from the pitcher plant Darlingtonia californica and cultured ‘artificial’ pitcher fluids and tested these fluids' prey retention capabilities. I found that cultures of pitcher leaves' bacterial communities had similar physical properties to raw pitcher fluids. These properties facilitated the retention of insects by both fluids and hint at a previously undescribed class of plant–microbe interaction. PMID:27881762

Bacteria facilitate prey retention by the pitcher plant Darlingtonia californica.

PubMed

Armitage, David W

2016-11-01

Bacteria are hypothesized to provide a variety of beneficial functions to plants. Many carnivorous pitcher plants, for example, rely on bacteria for digestion of captured prey. This bacterial community may also be responsible for the low surface tensions commonly observed in pitcher plant digestive fluids, which might facilitate prey capture. I tested this hypothesis by comparing the physical properties of natural pitcher fluid from the pitcher plant Darlingtonia californica and cultured 'artificial' pitcher fluids and tested these fluids' prey retention capabilities. I found that cultures of pitcher leaves' bacterial communities had similar physical properties to raw pitcher fluids. These properties facilitated the retention of insects by both fluids and hint at a previously undescribed class of plant-microbe interaction. © 2016 The Author(s).

Effect of reference conditions on flow rate, modifier fraction and retention in supercritical fluid chromatography.

PubMed

De Pauw, Ruben; Shoykhet Choikhet, Konstantin; Desmet, Gert; Broeckhoven, Ken

2016-08-12

When using compressible mobile phases such as fluidic CO2, the density, the volumetric flow rates and volumetric fractions are pressure dependent. The pressure and temperature definition of these volumetric parameters (referred to as the reference conditions) may alter between systems, manufacturers and operating conditions. A supercritical fluid chromatography system was modified to operate in two modes with different definition of the eluent delivery parameters, referred to as fixed and variable mode. For the variable mode, the volumetric parameters are defined with reference to the pump operating pressure and actual pump head temperature. These conditions may vary when, e.g. changing the column length, permeability, flow rate, etc. and are thus variable reference conditions. For the fixed mode, the reference conditions were set at 150bar and 30°C, resulting in a mass flow rate and mass fraction of modifier definition which is independent of the operation conditions. For the variable mode, the mass flow rate of carbon dioxide increases with system pump operating pressure, decreasing the fraction of modifier. Comparing the void times and retention factor shows that the deviation between the two modes is almost independent of modifier percentage, but depends on the operating pressure. Recalculating the set volumetric fraction of modifier to the mass fraction results in the same retention behaviour for both modes. This shows that retention in SFC can be best modelled using the mass fraction of modifier. The fixed mode also simplifies method scaling as it only requires matching average column pressure. Copyright © 2016 Elsevier B.V. All rights reserved.

Diffusion-limited retention of porous particles at density interfaces

PubMed Central

Kindler, Kolja; Khalili, Arzhang; Stocker, Roman

2010-01-01

Downward carbon flux in the ocean is largely governed by particle settling. Most marine particles settle at low Reynolds numbers and are highly porous, yet the fluid dynamics of this regime have remained unexplored. We present results of an experimental investigation of porous particles settling through a density interface at Reynolds numbers between 0.1 and 1. We tracked 100 to 500 μm hydrogel spheres with 95.5% porosity and negligible permeability. We found that a small negative initial excess density relative to the lower (denser) fluid layer, a common scenario in the ocean, results in long retention times of particles at the interface. We hypothesized that the retention time was determined by the diffusive exchange of the stratifying agent between interstitial and ambient fluid, which increases excess density of particles that have stalled at the interface, enabling their settling to resume. This hypothesis was confirmed by observations, which revealed a quadratic dependence of retention time on particle size, consistent with diffusive exchange. These results demonstrate that porosity can control retention times and therefore accumulation of particles at density interfaces, a mechanism that could underpin the formation of particle layers frequently observed at pycnoclines in the ocean. We estimate retention times of 3 min to 3.3 d for the characteristic size range of marine particles. This enhancement in retention time can affect carbon transformation through increased microbial colonization and utilization of particles and release of dissolved organics. The observed size dependence of the retention time could further contribute to improve quantifications of vertical carbon flux. PMID:21135242

Dielectric Interactions and the Prediction of Retention Times of Pesticides in Supercritical Fluid Chromatography with CO2

NASA Astrophysics Data System (ADS)

Alvarez, Guillermo A.; Baumanna, Wolfram

2005-02-01

A thermodynamic model for the partition of a solute (pesticide) between two immiscible phases, such as the stationary and mobile phases of supercritical fluid chromatography with CO2, is developed from first principles. A key ingredient of the model is the result of the calculation made by Liptay of the energy of interaction of a polar molecule with a dielectric continuum, which represents the solvent. The strength of the interaction between the solute and the solvent, which may be considered a measure of the solvent power, is characterized by a function g = (ɛ - 1)/(2ɛ +1), where ɛ is the dielectric constant of the medium, which is a function of the temperature T and the pressure P. Since the interactions between the nonpolar supercritical CO2 solvent and the slightly polar pesticide molecules are considered to be extremely weak, a regular solution model is appropriate from the thermodynamic point of view. At constant temperature, the model predicts a linear dependence of the logarithm of the capacity factor (lnk) of the chromatographic experiment on the function g = g(P), as the pressure is varied, with a slope which depends on the dipole moment of the solute, dispersion interactions and the size of the solute cavity in the solvent. At constant pressure, once the term containing the g (solvent interaction) factor is subtracted from lnk, a plot of the resulting term against the inverse of temperature yields the enthalpy change of transfer of the solute from the mobile (supercritical CO2) phase to the stationary (adsorbent) phase. The increase in temperature with the consequent large volume expansion of the supercritical fluid lowers its solvent strength and hence the capacity factor of the column (or solute retention time) increases. These pressure and temperature effects, predicted by the model, agree excellently with the experimental retention times of seven pesticides. Beyond a temperature of about 393 K, where the liquid solvent densities approach those of

Cold enzymatic bleaching of fluid whey.

PubMed

Campbell, R E; Drake, M A

2013-01-01

Chemical bleaching of fluid whey and retentate with hydrogen peroxide (HP) alone requires high concentrations (100-500 mg of HP/kg) and recent studies have demonstrated that off-flavors are generated during chemical bleaching that carry through to spray-dried whey proteins. Bleaching of fluid whey and retentate with enzymes such as naturally present lactoperoxidase or an exogenous commercial peroxidase (EP) at cold temperatures (4°C) may be a viable alternative to traditional chemical bleaching of whey. The objective of this study was to determine the optimum level of HP for enzymatic bleaching (both lactoperoxidase and EP) at 4°C and to compare bleaching efficacy and sensory characteristics to HP chemical bleaching at 4°C. Selected treatments were subsequently applied for whey protein concentrate with 80% protein (WPC80) manufacture. Fluid Cheddar whey and retentate (80% protein) were manufactured in triplicate from pasteurized whole milk. The optimum concentration of HP (0 to 250 mg/kg) to activate enzymatic bleaching at 4°C was determined by quantifying the loss of norbixin. In subsequent experiments, bleaching efficacy, descriptive sensory analysis, and volatile compounds were monitored at selected time points. A control with no bleaching was also evaluated. Enzymatic bleaching of fluid whey and retentate at 4°C resulted in faster bleaching and higher bleaching efficacy (color loss) than bleaching with HP alone at 250 mg/kg. Due to concentrated levels of naturally present lactoperoxidase, retentate bleached to completion (>80% norbixin destruction in 30 min) faster than fluid whey at 4°C (>80% norbixin destruction in 12h). In fluid whey, the addition of EP decreased bleaching time. Spray-dried WPC80 from bleached wheys, regardless of bleaching treatment, were characterized by a lack of sweet aromatic and buttery flavors, and the presence of cardboard flavor concurrent with higher relative abundance of 1-octen-3-ol and 1-octen-3-one. Among enzymatically

Re: Coagulation and Fluid Resuscitation by HyperHES in Severe Hemorrhage

DTIC Science & Technology

2013-08-01

aid kit, and we cannot envisage to load them with so much weight. In the context of trauma combat casualty care, fluid resuscitation byHyperHES...coagulation following femur injury and severe hemorrhage in pigs. J Trauma Acute Care Surg. 2013; 74(3):732Y740. 2. Dubick MA, Atkins JL. Small-volume...fluid resuscitation for the far-forward combat envi- ronment: current concepts. J Trauma . 2003;54: S43YS45. 3. Sharma P, Benford B, Karaian JE

[Improving myocardial mechanics parameters of severe burn rabbits with oral fluid resuscitation].

PubMed

Ruan, Jing; Zhang, Bing-qian; Wang, Guang; Luo, Zhong-hua; Zheng, Qing-yi; Zheng, Jian-sheng; Huang, Yue-sheng; Xiao, Rong

2008-08-01

To investigate the protective effect of oral fluid resuscitation on cardiac function in severe burn rabbits. One hundred and fifty rabbits were randomly divided into normal control group (NC group, n = 6, without treatment), burn group (B group, n = 42, without fluid therapy), immediate oral fluid resuscitation group (C group, n = 42), delayed oral fluid resuscitation group (D group, n = 30) and delayed and rapid oral fluid resuscitation group (E group, n = 30). The rabbits in B, C, D, E groups were subjected to 40% TBSA full-thickness burn, then were treated with fluid therapy immediately after burn (C group), at 6 hour after burn (D, E groups). The myocardial mechanics parameters including mean arterial pressure (MAP), left ventricular systolic pressure (LVSP), left ventricular end diastolic pressure (LVEDP), LV +/- dp/dt max were observed at 2, 6, 8, 12, 24, 36 and 48 post burn hour (PBH). Urine output was also examined. The level of LVSP, LV +/- dp/dt max in B roup were significantly lower than those in NC group. The level of LVSP, LV +/- dp/dt max in the C and E group were singnificantly increased during 24 hour after burn. The level of LV + dp/dt max and LV-dp/dt max in C group peaked at 8 PBH (892 +/- 116 kPa/s) and at 6PBH (724 +/- 149 kPa/s) respectively. The levels of LV +/- dp/dt max, LVSP in D group at each time point were similar to B group (P > 0.05). Both the levels of LV +/- dp/dt max in E group peaked at 8 PBH. The level of LVEDP was no obvious difference between B and other groups at each time point (P > 0.05). The changes of MAP and urine output on 24 PBH in each group were similar to above indices. Effective oral fluid therapy in severe burn rabbits during 24 hours after burn can ameliorate myocardial mechanics parameters. The amount of fluid resuscitation can be estimated according to relevant formula for delayed fluid resuscitation in burn rabbits.

Out-of-Hospital Fluid in Severe Sepsis: Effect on Early Resuscitation in the Emergency Department

PubMed Central

Seymour, Christopher W.; Cooke, Colin R.; Mikkelsen, Mark E.; Hylton, Julie; Rea, Tom D.; Goss, Christopher H.; Gaieski, David F.; Band, Roger A.

2014-01-01

Background Early identification and treatment of patients with severe sepsis improves outcome, yet the role of out-of-hospital intravenous (IV) fluid is unknown. Objective To determine if the delivery of out-of-hospital fluid in patients with severe sepsis is associated with reduced time to achievement of goal-oriented resuscitation in the emergency department (ED). Methods We performed a secondary data analysis of a retrospective cohort study in a metropolitan, tertiary care, university-based medical center supported by a two-tiered system of out-of-hospital emergency medical services (EMS) providers. We studied the association between delivery of out-of-hospital fluid by advanced life support (ALS) providers and the achievement of resuscitation endpoints (central venous pressure [CVP] ≥8 mmHg, mean arterial pressure [MAP] ≥65 mmHg, and central venous oxygen saturation [ScvO2] ≥70%) within six hours after triage during early goal-directed therapy (EGDT) in the ED. Results Twenty five (48%) of 52 patients transported by ALS with severe sepsis received out-of-hospital fluid. Data for age, gender, source of sepsis, and presence of comorbidities were similar between patients who did and did not receive out-of-hospital fluid. Patients receiving out-of-hospital fluid had lower out-of-hospital mean (± standard deviation) systolic blood pressure (95 ± 40 mmHg vs. 117 ± 29 mmHg; p = 0.03) and higher median (interquartile range) Sequential Organ Failure Assessment (SOFA) scores in the ED (7 [5–8] vs. 4 [4–6]; p = 0.01) than patients not receiving out-of-hospital fluid. Despite greater severity of illness, patients receiving out-of-hospital fluid approached but did not attain a statistically significant increase in the likelihood of achieving MAP ≥65 mmHg within six hours after ED triage (70% vs. 44%, p = 0.09). On average, patients receiving out-of-hospital fluid received twice the fluid volume within one hour after ED triage (1.1 L [1.0–2.0 L] vs. 0.6 L [0

Lubricant retention in liquid-infused microgrooves exposed to turbulent flow

NASA Astrophysics Data System (ADS)

Fu, Matthew; Chen, Ting-Hsuan; Arnold, Craig; Hultmark, Marcus

2017-11-01

Liquid infused surfaces are a promising method of passive drag reduction for turbulent flows. These surfaces rely on functionalized roughness elements to trap a liquid lubricant that is immiscible with external fluids. The presence of the lubricant creates a collection of fluid-fluid interfaces which can support a finite slip velocity at the effective surface. Generating a streamwise slip at the surface has been demonstrated as an effective mechanism for drag reduction; however, sustained drag reduction is predicated on the retention of the lubricating layer. Here, a turbulent channel-flow facility is used to characterize the robustness of liquid-infused surfaces and evaluate criteria for ensuring retention of the lubricant. Microscale grooved surfaces infused with alkane lubricants are mounted flush in the channel and exposed to turbulent flows. The retention of lubricants and pressure drop are monitored to characterize the effects of surface geometry and lubricant properties. To improve the retention of lubricant within grooved structures, a novel laser patterning technique is used to scribe chemical barriers onto grooved surfaces and evaluated. Supported under ONR Grants N00014-12-1-0875 and N00014-12-1-0962 (program manager Ki-Han Kim) and by the Department of Defense (DoD) through the National Defense Science & Engineering Graduate Fellowship (NDSEG) Program.

Systems and methods for the detection of low-level harmful substances in a large volume of fluid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carpenter, Michael V.; Roybal, Lyle G.; Lindquist, Alan

A method and device for the detection of low-level harmful substances in a large volume of fluid comprising using a concentrator system to produce a retentate and analyzing the retentate for the presence of at least one harmful substance. The concentrator system performs a method comprising pumping at least 10 liters of fluid from a sample source through a filter. While pumping, the concentrator system diverts retentate from the filter into a container. The concentrator system also recirculates at least part of the retentate in the container again through the filter. The concentrator system controls the speed of the pumpmore » with a control system thereby maintaining a fluid pressure less than 25 psi during the pumping of the fluid; monitors the quantity of retentate within the container with a control system, and maintains a reduced volume level of retentate and a target volume of retentate.« less

Global Regularity for Several Incompressible Fluid Models with Partial Dissipation

NASA Astrophysics Data System (ADS)

Wu, Jiahong; Xu, Xiaojing; Ye, Zhuan

2017-09-01

This paper examines the global regularity problem on several 2D incompressible fluid models with partial dissipation. They are the surface quasi-geostrophic (SQG) equation, the 2D Euler equation and the 2D Boussinesq equations. These are well-known models in fluid mechanics and geophysics. The fundamental issue of whether or not they are globally well-posed has attracted enormous attention. The corresponding models with partial dissipation may arise in physical circumstances when the dissipation varies in different directions. We show that the SQG equation with either horizontal or vertical dissipation always has global solutions. This is in sharp contrast with the inviscid SQG equation for which the global regularity problem remains outstandingly open. Although the 2D Euler is globally well-posed for sufficiently smooth data, the associated equations with partial dissipation no longer conserve the vorticity and the global regularity is not trivial. We are able to prove the global regularity for two partially dissipated Euler equations. Several global bounds are also obtained for a partially dissipated Boussinesq system.

Fluid Pressures at the Shoe-Floor-Contaminant Interface During Slips: Effects of Tread & Implications on Slip Severity

PubMed Central

Beschorner, Kurt E.; Albert, Devon L.; Chambers, April J.; Redfern, Mark S.

2018-01-01

Previous research on slip and fall accidents has suggested that pressurized fluid between the shoe and floor is responsible for initiating slips yet this effect has not been verified experimentally. This study aimed to 1) measure hydrodynamic pressures during slipping for treaded and untreaded conditions; 2) determine the effects of fluid pressure on slip severity; and 3) quantify how fluid pressures vary with instantaneous resultant slipping speed, position on the shoe surface, and throughout the progression of the slip. Eighteen subjects walked on known dry and unexpected slippery floors, while wearing treaded and untreaded shoes. Fluid pressure sensors, embedded in the floor, recorded hydrodynamic pressures during slipping. The maximum fluid pressures (mean+/−standard deviation) were significantly higher for the untreaded conditions (124 +/−75 kPa) than the treaded conditions (1.1 +/−0.29 kPa). Maximum fluid pressures were positively correlated with peak slipping speed (r = 0.87), suggesting that higher fluid pressures, which are associated with untreaded conditions, resulted in more severe slips. Instantaneous resultant slipping speed and position of sensor relative to the shoe sole and walking direction explained 41% of the fluid pressure variability. Fluid pressures were primarily observed for untreaded conditions. This study confirms that fluid pressures are relevant to slipping events, consistent with fluid dynamics theory (i.e. the Reynolds equation), and can be modified with shoe tread design. The results suggest that the occurrence and severity of unexpected slips can be reduced by designing shoes/floors that reduce underfoot fluid pressures. PMID:24267270

Cerebrospinal fluid PCR analysis and biochemistry in bodies with severe decomposition.

PubMed

Palmiere, Cristian; Vanhaebost, Jessica; Ventura, Francesco; Bonsignore, Alessandro; Bonetti, Luca Reggiani

2015-02-01

The aim of this study was to assess whether Neisseria meningitidis, Listeria monocytogenes, Streptococcus pneumoniae and Haemophilus influenzae can be identified using the polymerase chain reaction technique in the cerebrospinal fluid of severely decomposed bodies with known, noninfectious causes of death or whether postmortem changes can lead to false positive results and thus erroneous diagnostic information. Biochemical investigations, postmortem bacteriology and real-time polymerase chain reaction analysis in cerebrospinal fluid were performed in a series of medico-legal autopsies that included noninfectious causes of death with decomposition, bacterial meningitis without decomposition, bacterial meningitis with decomposition, low respiratory tract infections with decomposition and abdominal infections with decomposition. In noninfectious causes of death with decomposition, postmortem investigations failed to reveal results consistent with generalized inflammation or bacterial infections at the time of death. Real-time polymerase chain reaction analysis in cerebrospinal fluid did not identify the studied bacteria in any of these cases. The results of this study highlight the usefulness of molecular approaches in bacteriology as well as the use of alternative biological samples in postmortem biochemistry in order to obtain suitable information even in corpses with severe decompositional changes. Copyright © 2014 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Noble gases in gas shales : Implications for gas retention and circulating fluids.

NASA Astrophysics Data System (ADS)

Basu, Sudeshna; Jones, Adrian; Verchovsky, Alexander

2016-04-01

Gas shales from three cores of Haynesville-Bossier formation have been analysed simultaneously for carbon, nitrogen and noble gases (He, Ne, Ar, Xe) to constrain their source compositions and identify signatures associated with high gas retention. Ten samples from varying depths of 11785 to 12223 feet from each core, retrieved from their centres, have been combusted from 200-1200°C in incremental steps of 100°C, using 5 - 10 mg of each sample. Typically, Xe is released at 200°C and is largely adsorbed, observed in two of the three cores. The third core lacked any measureable Xe. High 40Ar/36Ar ratio up to 8000, is associated with peak release of nitrogen with distinctive isotopic signature, related to breakdown of clay minerals at 500°C. He and Ne are also mostly released at the same temperature step and predominantly hosted in the pore spaces of the organic matter associated with the clay. He may be produced from the uranium related to the organic matter. The enrichment factors of noble gases defined as (iX/36Ar)sample/(iX/36Ar)air where iX denotes any noble gas isotope, show Ne and Xe enrichment observed commonly in sedimentary rocks including shales (Podosek et al., 1980; Bernatowicz et al., 1984). This can be related to interaction of the shales with circulating fluids and diffusive separation of gases (Torgersen and Kennedy, 1999), implying the possibility of loss of gases from these shales. Interaction with circulating fluids (e.g. crustal fluids) have been further confirmed using 20Ne/N2, 36Ar/N2 and 4He/N2 ratios. Deviations of measured 4He/40Ar* (where 40Ar* represents radiogenic 40Ar after correcting for contribution from atmospheric Ar) from expected values has been used to monitor gas loss by degassing. Bernatowicz, T., Podosek, F.A., Honda, M., Kramer, F.E., 1984. The Atmospheric Inventory of Xenon and Noble Gases in Shales: The Plastic Bag Experiment. Journal of Geophysical Research 89, 4597-4611. Podosek, F.A., Honda, M., Ozima, M., 1980

Fluid overload and kidney failure in children with severe sepsis and septic shock: A cohort study.

PubMed

Naveda Romero, Omar E; Naveda Meléndez, Andrea F

2017-04-01

In children with sepsis, fluid overload as a result of an aggressive fluid replacement or excessive fluid administration may result in kidney impairment and increased mortality. Objective. To determine the association between fluid overload and the rate of kidney failure in a group of children with severe sepsis and septic shock. This was a prospective cohort study conducted in the intensive care unit of Hospital Universitario de Pediatría “Dr. Agustín Zubillaga” (Barquisimeto, Lara State, Venezuela), between March 2013 and May 2016, in children with severe sepsis or septic shock. One hundred and forty-nine patients were included in the analysis. Sepsis predominated in 59.7% of cases; patients' average age was 6.4 ± 3.3 years old, their average weight was 17.8 ± 3.6 kg, 30.2% had fluid overload, and overall mortality was 25.5%. Kidney failure occurred in 16.1% of cases. A binary logistic regression model was used to identify fluid overload (odds ratio [OR]: 1.5; 95% confidence interval [CI]: 1.2-4.9, p = 0.028) and shock for more than 2 days (OR: 1.7; 95% CI: 1.3-6.3, p = 0.039) as independent predictors of kidney failure. In addition, a significant increase in the risk of mortality among children with kidney failure and fluid overload was observed as per the Kaplan-Meier method (p= 0.019). Fluid overload and shock for more than 2 days increase the risk for kidney failure in critically ill children with severe sepsis and septic shock.

Mortality after fluid bolus in African children with severe infection.

PubMed

Maitland, Kathryn; Kiguli, Sarah; Opoka, Robert O; Engoru, Charles; Olupot-Olupot, Peter; Akech, Samuel O; Nyeko, Richard; Mtove, George; Reyburn, Hugh; Lang, Trudie; Brent, Bernadette; Evans, Jennifer A; Tibenderana, James K; Crawley, Jane; Russell, Elizabeth C; Levin, Michael; Babiker, Abdel G; Gibb, Diana M

2011-06-30

The role of fluid resuscitation in the treatment of children with shock and life-threatening infections who live in resource-limited settings is not established. We randomly assigned children with severe febrile illness and impaired perfusion to receive boluses of 20 to 40 ml of 5% albumin solution (albumin-bolus group) or 0.9% saline solution (saline-bolus group) per kilogram of body weight or no bolus (control group) at the time of admission to a hospital in Uganda, Kenya, or Tanzania (stratum A); children with severe hypotension were randomly assigned to one of the bolus groups only (stratum B). All children received appropriate antimicrobial treatment, intravenous maintenance fluids, and supportive care, according to guidelines. Children with malnutrition or gastroenteritis were excluded. The primary end point was 48-hour mortality; secondary end points included pulmonary edema, increased intracranial pressure, and mortality or neurologic sequelae at 4 weeks. The data and safety monitoring committee recommended halting recruitment after 3141 of the projected 3600 children in stratum A were enrolled. Malaria status (57% overall) and clinical severity were similar across groups. The 48-hour mortality was 10.6% (111 of 1050 children), 10.5% (110 of 1047 children), and 7.3% (76 of 1044 children) in the albumin-bolus, saline-bolus, and control groups, respectively (relative risk for saline bolus vs. control, 1.44; 95% confidence interval [CI], 1.09 to 1.90; P=0.01; relative risk for albumin bolus vs. saline bolus, 1.01; 95% CI, 0.78 to 1.29; P=0.96; and relative risk for any bolus vs. control, 1.45; 95% CI, 1.13 to 1.86; P=0.003). The 4-week mortality was 12.2%, 12.0%, and 8.7% in the three groups, respectively (P=0.004 for the comparison of bolus with control). Neurologic sequelae occurred in 2.2%, 1.9%, and 2.0% of the children in the respective groups (P=0.92), and pulmonary edema or increased intracranial pressure occurred in 2.6%, 2.2%, and 1.7% (P=0

[Clinical evaluation of the postburn retention and the metabolism of Imipenem in the third space].

PubMed

Rong, Xin-Zhou; Bei, Chun-Hua; Huang, Xiao-Hua; Li, Qing-Hui

2003-04-01

To explore the half life and retention of Imipenem in the third space. Eight severely burned patients and eight healthy volunteers were enrolled as the burn group (B) and normal control group (C), respectively. HPLC (high performance liquid chromatography) was employed to determine the contents of Imipenem in the plasma, subeschar tissue fluid (STF) and the changes in its pharmacokinetics. Furthermore, the Imipenem content in the third space was calculated according to the systemic edema degree. The half life of Imipenem in STF (2.53 h) was longer than that in plasma (1.73 h), P < 0.05). The Imipenem content in STF increased gradually along with the lapse of time after repeated intravenous infusion of Imipenem, and at the same the total content of imipenem was increased significantly in the third space. There was antibiotic retention in the third space after severe burn injury, and a prolonged action of the drug could be expected when the drug re-entered the blood stream.

[FEATURES OF FLUID THERAPY IN CHILDREN WITH SEVERE MAJOR TRAUMA].

PubMed

Pshenisnov, K V; Aleksandrovich, Yu S; Mironov, P I; Suhanov, Yu V; Kuzmin, O V; Blinov, S A; Kondin, A N

2016-01-01

Fluid and transfusion therapy is proved to be a required component of treating children with severe major trauma significantly influencing the case outcome. To analyze efficiency of fluid and transfusion therapy in children with severe major trauma and assess its correspondence with current recommendations. 150 children aged from 0 to 18 years getting treatment in intensive care units of children's city hospitals of Saint Petersburg, Archangelsk, Ufa, Samara, and Leningrad region were included in the research. The main course of severe major trauma were car injury and catatrauma. The coefficient according to Pediatric trauma score (PTS) was 6.4 points. The mean duration of hospitalization in emergencies units was 3 (2-7) days, the duration of artificial lung ventilation was 48 ± 99.9 hours, the duration of hospitalization in the department ward was 24 (15-32) days. Favorable outcome (transferring from emergencies units to department wards) was reported in 147 (98%) children, death cases were registered in 4 (2.6%) children. There was determined that the basic crystalloid solutions used for infusion therapy in children were the following: Ringer solution, Plasma-lit solution and 10% glucose solution. "Gelofisin" and "Voluven" had more frequent administration rate among colloidal solutions. Transfusion of blood was performed in 26% patients. The infusion therapy in the first three days did not exceed the necessary physiological requirements that provided stabilization of the patient's condition and did not produce a negative influence on the status of hemodynamics and gas exchange. Administration of current well-balanced crystalloid and colloidal solutions to children with severe combined trauma in an amount within the limits of required physiological indicators does not produce a negative influence on the status of gas exchange and the case outcome.

Thiel embalming fluid--a new way to revive formalin-fixed cadaveric specimens.

PubMed

Hunter, Amanda; Eisma, Roos; Lamb, Clare

2014-09-01

By soft fixing cadavers using the Thiel embalming method, our cadavers now exhibit a greater degree of flexibility and color retention compared to that of traditional formalin-fixed cadavers. The aim of this experiment was to discover whether Thiel embalming fluid could be used to revive and soften the muscles of formalin-fixed prosected specimens. Earlier this year, two severely dehydrated formalin-fixed forearm and hand specimens were fully submerged in a tank containing Thiel embalming fluid. After a period of six months the specimens were removed from the tank and noticeable changes were observed in flexibility, quality of the tissue, and color of the specimens. © 2014 Wiley Periodicals, Inc.

Balanced Fluid Versus Saline-Based Fluid in Post-operative Severe Traumatic Brain Injury Patients: Acid-Base and Electrolytes Assessment

PubMed Central

Hassan, Mohamad Hasyizan; Hassan, Wan Mohd Nazaruddin Wan; Zaini, Rhendra Hardy Mohd; Shukeri, Wan Fadzlina Wan Muhd; Abidin, Huda Zainal; Eu, Chong Soon

2017-01-01

Background Normal saline (NS) is a common fluid of choice in neurosurgery and neuro-intensive care unit (ICU), but it does not contain other electrolytes and has the potential to cause hyperchloremic metabolic acidosis with prolonged infusion. These problems may be reduced with the availability of balanced fluid (BF), which becomes a more physiological isotonic solution with the presence of complete electrolyte content. This study aimed to compare the changes in electrolytes and acid–base between NS and BF (Sterofundin® ISO) therapy for post-operative severe traumatic brain injury (TBI) patients in neuro-ICU. Methods Sixty-six severe TBI patients who required emergency craniotomy or craniectomy and were planned for post-operative ventilation were randomised into NS (n = 33) and BF therapy groups (n = 33). The calculation of maintenance fluid given was based on the Holliday-Segar method. The electrolytes and acid–base parameters were assessed at an 8 h interval for 24 h. The data were analysed using repeated measures ANOVA. Results The NS group showed a significant lower base excess (−3.20 versus −1.35, P = 0.049), lower bicarbonate level (22.03 versus 23.48 mmol/L, P = 0.031), and more hyperchloremia (115.12 versus 111.74 mmol/L, P < 0.001) and hypokalemia (3.36 versus 3.70 mmol/L, P < 0.001) than the BF group at 24 h of therapy. The BF group showed a significantly higher level of calcium (1.97 versus 1.79 mmol/L, P = 0.003) and magnesium (0.94 versus 0.80 mmol/L, P < 0.001) than the NS group at 24 h of fluid therapy. No significant differences were found in pH, pCO2, lactate, and sodium level. Conclusion BF therapy showed better effects in maintaining higher electrolyte parameters and reducing the trend toward hyperchloremic metabolic acidosis than the NS therapy during prolonged fluid therapy for postoperative TBI patients. PMID:29386975

Balanced Fluid Versus Saline-Based Fluid in Post-operative Severe Traumatic Brain Injury Patients: Acid-Base and Electrolytes Assessment.

PubMed

Hassan, Mohamad Hasyizan; Hassan, Wan Mohd Nazaruddin Wan; Zaini, Rhendra Hardy Mohd; Shukeri, Wan Fadzlina Wan Muhd; Abidin, Huda Zainal; Eu, Chong Soon

2017-10-01

Normal saline (NS) is a common fluid of choice in neurosurgery and neuro-intensive care unit (ICU), but it does not contain other electrolytes and has the potential to cause hyperchloremic metabolic acidosis with prolonged infusion. These problems may be reduced with the availability of balanced fluid (BF), which becomes a more physiological isotonic solution with the presence of complete electrolyte content. This study aimed to compare the changes in electrolytes and acid-base between NS and BF (Sterofundin® ISO) therapy for post-operative severe traumatic brain injury (TBI) patients in neuro-ICU. Sixty-six severe TBI patients who required emergency craniotomy or craniectomy and were planned for post-operative ventilation were randomised into NS ( n = 33) and BF therapy groups ( n = 33). The calculation of maintenance fluid given was based on the Holliday-Segar method. The electrolytes and acid-base parameters were assessed at an 8 h interval for 24 h. The data were analysed using repeated measures ANOVA. The NS group showed a significant lower base excess (-3.20 versus -1.35, P = 0.049), lower bicarbonate level (22.03 versus 23.48 mmol/L, P = 0.031), and more hyperchloremia (115.12 versus 111.74 mmol/L, P < 0.001) and hypokalemia (3.36 versus 3.70 mmol/L, P < 0.001) than the BF group at 24 h of therapy. The BF group showed a significantly higher level of calcium (1.97 versus 1.79 mmol/L, P = 0.003) and magnesium (0.94 versus 0.80 mmol/L, P < 0.001) than the NS group at 24 h of fluid therapy. No significant differences were found in pH, pCO 2 , lactate, and sodium level. BF therapy showed better effects in maintaining higher electrolyte parameters and reducing the trend toward hyperchloremic metabolic acidosis than the NS therapy during prolonged fluid therapy for postoperative TBI patients.

Unsupervised parameter optimization for automated retention time alignment of severely shifted gas chromatographic data using the piecework alignment algorithm.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pierce, Karisa M.; Wright, Bob W.; Synovec, Robert E.

2007-02-02

First, simulated chromatographic separations with declining retention time precision were used to study the performance of the piecewise retention time alignment algorithm and to demonstrate an unsupervised parameter optimization method. The average correlation coefficient between the first chromatogram and every other chromatogram in the data set was used to optimize the alignment parameters. This correlation method does not require a training set, so it is unsupervised and automated. This frees the user from needing to provide class information and makes the alignment algorithm more generally applicable to classifying completely unknown data sets. For a data set of simulated chromatograms wheremore » the average chromatographic peak was shifted past two neighboring peaks between runs, the average correlation coefficient of the raw data was 0.46 ± 0.25. After automated, optimized piecewise alignment, the average correlation coefficient was 0.93 ± 0.02. Additionally, a relative shift metric and principal component analysis (PCA) were used to independently quantify and categorize the alignment performance, respectively. The relative shift metric was defined as four times the standard deviation of a given peak’s retention time in all of the chromatograms, divided by the peak-width-at-base. The raw simulated data sets that were studied contained peaks with average relative shifts ranging between 0.3 and 3.0. Second, a “real” data set of gasoline separations was gathered using three different GC methods to induce severe retention time shifting. In these gasoline separations, retention time precision improved ~8 fold following alignment. Finally, piecewise alignment and the unsupervised correlation optimization method were applied to severely shifted GC separations of reformate distillation fractions. The effect of piecewise alignment on peak heights and peak areas is also reported. Piecewise alignment either did not change the peak height, or caused it to

Modelling fluid accumulation in the neck using simple baseline fluid metrics: implications for sleep apnea.

PubMed

Vena, Daniel; Yadollahi, A; Bradley, T Douglas

2014-01-01

Obstructive sleep apnea (OSA) is a common respiratory disorder among adults. Recently we have shown that sedentary lifestyle causes an increase in diurnal leg fluid volume (LFV), which can shift into the neck at night when lying down to sleep and increase OSA severity. The purpose of this work was to investigate various metrics that represent baseline fluid retention in the legs and examine their correlation with neck fluid volume (NFV) and to develop a robust model for predicting fluid accumulation in the neck. In 13 healthy awake non-obese men, LFV and NFV were recorded continuously and simultaneously while standing for 5 minutes and then lying supine for 90 minutes. Simple regression was used to examine correlations between baseline LFV, baseline neck circumference (NC) and change in LFV with the outcome variables: change in NC (ΔNC) and in NFV (ΔNFV90) after lying supine for 90 minutes. An exhaustive grid search was implemented to find combinations of input variables which best modeled outcomes. We found strong positive correlations between baseline LFV (supine and standing) and ΔNFV90. Models developed for predicting ΔNFV90 included baseline standing LFV, baseline NC combined with change in LFV after lying supine for 90 minutes. These correlations and the developed models suggest that a greater baseline LFV might contribute to increased fluid accumulation in the neck. These results give more evidence that sedentary lifestyle might play a role in the pathogenesis of OSA by increasing the baseline LFV. The best models for predicting ΔNC include baseline LFV and NC; they improved accuracies of estimating ΔNC over individual predictors, suggesting that a combination of baseline fluid metrics is a good predictor of the change in NC while lying supine. Future work is aimed at adding additional baseline demographic features to improve model accuracy and eventually use it as a screening tool to predict severity of OSA prior to sleep.

Spironolactone reduces severity of obstructive sleep apnoea in patients with resistant hypertension: a preliminary report.

PubMed

Gaddam, K; Pimenta, E; Thomas, S J; Cofield, S S; Oparil, S; Harding, S M; Calhoun, D A

2010-08-01

Obstructive sleep apnoea (OSA) and hyperaldosteronism are very common in subjects with resistant hypertension. We hypothesized that aldosterone-mediated chronic fluid retention may influence OSA severity in patients with resistant hypertension. We tested this in an open-label evaluation by assessing the changes in the severity of OSA in patients with resistant hypertension after treatment with spironolactone. Subjects with resistant hypertension (clinical blood pressure (BP) >or=140/90 mm Hg on >or=3 antihypertensive medications, including a thiazide diuretic and OSA (defined as an apnoea-hypopnoea index (AHI) >or=15) had full diagnostic, polysomnography before and 8 weeks after spironolactone (25-50 mg a day) was added to their ongoing antihypertensive therapy. In all, 12 patients (mean age 56 years and body mass index 36.8 kg m(-2)) were evaluated. After treatment with spironolactone, the AHI (39.8+/-19.5 vs 22.0+/-6.8 events/h; P<0.05) and hypoxic index (13.6+/-10.8 vs 6.7+/-6.6 events/h; P<0.05), weight and clinic and ambulatory BP were significantly reduced. Plasma renin activity (PRA) and serum creatinine were significantly higher. This study provides preliminary evidence that treatment with a mineralocorticoid receptor antagonist substantially reduces the severity of OSA. If confirmed in a randomized assessment, it will support aldosterone-mediated chronic fluid retention as an important mediator of OSA severity in patients with resistant hypertension.

[Fluid management and cause of death during shock period in patients with severe burns or burns complicated by inhalation injury].

PubMed

Zhang, Ming-liang; Li, Chi; Ma, Chun-xu

2003-11-01

To explore fluid management and cause of death during shock period in severe burns or burns with inhalation injury. One hundred and twelve patients with severe burns or burn complicated by inhalation injury admitted to our hospital from 1991 to 2000 were analyzed. The fluid management and death conditions during shock period were discussed. The fluid volume for resuscitation could be described as follows: the total fluid volume was 2.2 ml/(%TBSA.kg) including colloid fluid 0.5 ml/(%TBSA.kg), crystalloid fluid 1 ml/(%TBSA.kg)and water 0.7 ml/(%TBSA.kg) during first 24 hours. The total fluid volume was 1.8 ml/(%TBSA.kg) including colloid fluid 0.4 ml/(%TBSA.kg), crystalloid fluid 0.7 ml/(%TBSA.kg) and water 0.7 ml/(%TBSA.kg) during second 24 hours. There were no difference in fluid management between burns and burns with inhalation injury. Seven patients died due to respiratory failure during shock period. Many fluid formula can provide guidance for resuscitation and it is very important that early fluid therapy should accord with concrete clinical conditions of patients in order to pass smoothly through shock period. Early fluid management is not different between burns and burns with inhalation injury.

Fluid retention, muscle damage, and altered body composition at the Ultraman triathlon.

PubMed

Baur, Daniel A; Bach, Christopher W; Hyder, William J; Ormsbee, Michael J

2016-03-01

The primary purpose of this investigation was to determine the effects of participation in a 3-day multistage ultraendurance triathlon (stage 1 = 10 km swim, 144.8 km bike; stage 2 = 275.4 km bike; stage 3 = 84.4 km run) on body mass and composition, hydration status, hormones, muscle damage, and blood glucose. Eighteen triathletes (mean ± SD; age 41 ± 7.5 years; height 175 ± 9 cm; weight 73.5 ± 9.8 kg; male n = 14, female n = 4) were assessed before and after each stage of the race. Body mass and composition were measured via bioelectrical impedance, hydration status via urine specific gravity, hormones and muscle damage via venous blood draw, and blood glucose via fingerstick. Following the race, significant changes included reductions in body mass (qualified effect size: trivial), fat mass (moderate), and percent body fat (small); increases in percent total body water (moderate) and urine specific gravity (large); and unchanged absolute total body water and fat-free mass. There were also extremely large increases in creatine kinase, C-reactive protein, aldosterone and cortisol combined with reductions in testosterone (small) and the testosterone:cortisol ratio (moderate). There were associations between post-race aldosterone and total body water (r = -0.504) and changes in cortisol and fat-free mass (r = -0.536). Finally, blood glucose increased in a stepwise manner prior to each stage. Participation in Ultraman Florida leads to fluid retention and dramatic alterations in body composition, muscle health, hormones, and metabolism.

Vitamin B12 deficiency results in severe oxidative stress, leading to memory retention impairment in Caenorhabditis elegans.

PubMed

Bito, Tomohiro; Misaki, Taihei; Yabuta, Yukinori; Ishikawa, Takahiro; Kawano, Tsuyoshi; Watanabe, Fumio

2017-04-01

Oxidative stress is implicated in various human diseases and conditions, such as a neurodegeneration, which is the major symptom of vitamin B 12 deficiency, although the underlying disease mechanisms associated with vitamin B 12 deficiency are poorly understood. Vitamin B 12 deficiency was found to significantly increase cellular H 2 O 2 and NO content in Caenorhabditis elegans and significantly decrease low molecular antioxidant [reduced glutathione (GSH) and L-ascorbic acid] levels and antioxidant enzyme (superoxide dismutase and catalase) activities, indicating that vitamin B 12 deficiency induces severe oxidative stress leading to oxidative damage of various cellular components in worms. An NaCl chemotaxis associative learning assay indicated that vitamin B 12 deficiency did not affect learning ability but impaired memory retention ability, which decreased to approximately 58% of the control value. When worms were treated with 1mmol/L GSH, L-ascorbic acid, or vitamin E for three generations during vitamin B 12 deficiency, cellular malondialdehyde content as an index of oxidative stress decreased to the control level, but the impairment of memory retention ability was not completely reversed (up to approximately 50%). These results suggest that memory retention impairment formed during vitamin B 12 deficiency is partially attributable to oxidative stress. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Smart Fluids in Hydrology: Use of Non-Newtonian Fluids for Pore Structure Characterization

NASA Astrophysics Data System (ADS)

Abou Najm, M. R.; Atallah, N. M.; Selker, J. S.; Roques, C.; Stewart, R. D.; Rupp, D. E.; Saad, G.; El-Fadel, M.

2015-12-01

Classic porous media characterization relies on typical infiltration experiments with Newtonian fluids (i.e., water) to estimate hydraulic conductivity. However, such experiments are generally not able to discern important characteristics such as pore size distribution or pore structure. We show that introducing non-Newtonian fluids provides additional unique flow signatures that can be used for improved pore structure characterization while still representing the functional hydraulic behavior of real porous media. We present a new method for experimentally estimating the pore structure of porous media using a combination of Newtonian and non-Newtonian fluids. The proposed method transforms results of N infiltration experiments using water and N-1 non-Newtonian solutions into a system of equations that yields N representative radii (Ri) and their corresponding percent contribution to flow (wi). This method allows for estimating the soil retention curve using only saturated experiments. Experimental and numerical validation comparing the functional flow behavior of different soils to their modeled flow with N representative radii revealed the ability of the proposed method to represent the water retention and infiltration behavior of real soils. The experimental results showed the ability of such fluids to outsmart Newtonian fluids and infer pore size distribution and unsaturated behavior using simple saturated experiments. Specifically, we demonstrate using synthetic porous media that the use of different non-Newtonian fluids enables the definition of the radii and corresponding percent contribution to flow of multiple representative pores, thus improving the ability of pore-scale models to mimic the functional behavior of real porous media in terms of flow and porosity. The results advance the knowledge towards conceptualizing the complexity of porous media and can potentially impact applications in fields like irrigation efficiencies, vadose zone hydrology, soil

Acute urinary retention due to benign inflammatory nervous diseases.

PubMed

Sakakibara, Ryuji; Yamanishi, Tomonori; Uchiyama, Tomoyuki; Hattori, Takamichi

2006-08-01

Both neurologists and urologists might encounter patients with acute urinary retention due to benign inflammatory nervous diseases. Based on the mechanism of urinary retention, these disorders can be divided into two subgroups: disorders of the peripheral nervous system (e.g., sacral herpes) or the central nervous system (e.g., meningitis-retention syndrome [MRS]). Laboratory abnormalities include increased herpes virus titers in sacral herpes, and increased myelin basic protein in the cerebrospinal fluid (CSF) in some cases with MRS. Urodynamic abnormality in both conditions is detrusor areflexia; the putative mechanism of it is direct involvement of the pelvic nerves in sacral herpes; and acute spinal shock in MRS. There are few cases with CSF abnormality alone. Although these cases have a benign course, management of the acute urinary retention is necessary to avoid bladder injury due to overdistension. Clinical features of sacral herpes or MRS differ markedly from those of the original "Elsberg syndrome" cases.

Exploratory Application of Neuropharmacometabolomics in Severe Childhood Traumatic Brain Injury.

PubMed

Hagos, Fanuel T; Empey, Philip E; Wang, Pengcheng; Ma, Xiaochao; Poloyac, Samuel M; Bayır, Hülya; Kochanek, Patrick M; Bell, Michael J; Clark, Robert S B

2018-05-07

To employ metabolomics-based pathway and network analyses to evaluate the cerebrospinal fluid metabolome after severe traumatic brain injury in children and the capacity of combination therapy with probenecid and N-acetylcysteine to impact glutathione-related and other pathways and networks, relative to placebo treatment. Analysis of cerebrospinal fluid obtained from children enrolled in an Institutional Review Board-approved, randomized, placebo-controlled trial of a combination of probenecid and N-acetylcysteine after severe traumatic brain injury (Trial Registration NCT01322009). Thirty-six-bed PICU in a university-affiliated children's hospital. Twelve children 2-18 years old after severe traumatic brain injury and five age-matched control subjects. Probenecid (25 mg/kg) and N-acetylcysteine (140 mg/kg) or placebo administered via naso/orogastric tube. The cerebrospinal fluid metabolome was analyzed in samples from traumatic brain injury patients 24 hours after the first dose of drugs or placebo and control subjects. Feature detection, retention time, alignment, annotation, and principal component analysis and statistical analysis were conducted using XCMS-online. The software "mummichog" was used for pathway and network analyses. A two-component principal component analysis revealed clustering of each of the groups, with distinct metabolomics signatures. Several novel pathways with plausible mechanistic involvement in traumatic brain injury were identified. A combination of metabolomics and pathway/network analyses showed that seven glutathione-centered pathways and two networks were enriched in the cerebrospinal fluid of traumatic brain injury patients treated with probenecid and N-acetylcysteine versus placebo-treated patients. Several additional pathways/networks consisting of components that are known substrates of probenecid-inhibitable transporters were also identified, providing additional mechanistic validation. This proof

On colloid retention in saturated porous media in the presence of energy barriers: The failure of α, and opportunities to predict η

NASA Astrophysics Data System (ADS)

Johnson, William P.; Tong, Meiping; Li, Xiqing

2007-12-01

This contribution reviews recent findings that illuminate the processes governing colloid retention in porous media under environmentally relevant conditions. In the environment, colloids act as conveyors of contaminants, or even as contaminants themselves; however, despite decades of research, we are unable to accurately predict the retention of colloids in granular aquifer media under environmental conditions, where repulsion exists between colloids and surfaces. This failure cannot be blamed solely on the complexities of the subsurface, since colloid filtration theory (CFT) works well in the absence of colloid-collector repulsion despite its idealization of porous media as consisting of spherical grains completely surrounded by fluid envelopes. Rather, the failure of CFT stems from failure to incorporate the correct mechanisms of retention when repulsion exists. Recent observations implicate wedging in grain-to-grain contacts and retention in secondary energy minima as dominant mechanisms of colloid retention in the presence of an energy barrier. Mechanistic simulations in unit cells containing grain-to-grain contacts corroborate these mechanisms of colloid retention. The resulting concept for colloid retention in the presence of an energy barrier involves translation of colloids across the collector surfaces until they become wedged within grain-to-grain contacts, or are retained via secondary energy minima (without attachment) in zones where the balance of fluid drag, diffusion, gravitational, and colloid-collector interaction forces allow retention. The above findings highlight the pore domain geometry as a dominant governor of colloid retention in so far as the geometry gives rise to grain-to-grain contacts and zones of relatively low fluid drag.

The use of lithium as a marker for the retention of liquids in the oral cavity after rinsing.

PubMed

Hanning, Sara M; Kieser, Jules A; Ferguson, Martin M; Reid, Malcolm; Medlicott, Natalie J

2014-01-01

The aim of this study was to validate the use of lithium as a marker to indicate the retention of simple liquids in the oral cavity and use this to determine how much liquid is retained in the oral cavity following 30 s of rinsing. This is a validation study in which saliva was spiked with known concentrations of lithium. Twenty healthy participants then rinsed their mouths with either water or a 1 % w/v carboxymethylcellulose (CMC) solution for 30 s before expectorating into a collection cup. Total volume and concentration of lithium in the expectorant were then measured, and the percentage of liquid retained was calculated. The mean amount of liquid retained was 10.4 ± 4.7 % following rinsing with water and 15.3 ± 4.1 % following rinsing with 1 % w/v CMC solution. This difference was significant (p < 0.01). Lithium was useful as a marker for the retention of liquids in the oral cavity, and a value for the amount of water and 1 % w/v CMC solution remaining in the oral cavity following a 30-s rinse was established. The present study quantifies the retention of simple fluids in the oral cavity, validating a technique that may be applied to more complex fluids such as mouth rinses. Further, the application of this method to specific population groups such as those with severe xerostomia may assist in developing effective saliva substitutes.

A randomized, double crossover study to investigate the influence of saline infusion on sleep apnea severity in men.

PubMed

Yadollahi, Azadeh; Gabriel, Joseph M; White, Laura H; Taranto Montemurro, Luigi; Kasai, Takatoshi; Bradley, T Douglas

2014-10-01

Obstructive sleep apnea (OSA) is commoner in patients with fluid-retaining states than in those without fluid retention, in men than in women, and worsens with aging. In men, OSA severity is related to the amount of fluid shifting out of the legs overnight, but a cause-effect relationship is not established. Our objective was to test the hypothesis that mimicking fluid overload during sleep would increase severity of OSA more in older (≥ 40 years) than in younger men (< 40 years). Randomized, single-blind, double crossover study. Research sleep laboratory. Seven older and 10 younger men with non-severe or no sleep apnea, matched for body mass index. During the control arm, normal saline was infused to keep the vein open. During intervention, subjects received an intravenous bolus of normal saline (22 mL/kg body weight) after sleep onset while they were wearing compression stockings to prevent fluid accumulation in the legs. Compared to younger men, infusion of similar amounts of saline in older men caused a greater increase in neck circumference (P < 0.05) and in the AHI (32.2 ± 22.1 vs. 2.2 ± 7.1, P = 0.002). Older men are more susceptible to the adverse effects of intravenous fluid loading on obstructive sleep apnea severity than younger men. This may be due to age-related differences in the amount of fluid accumulating in the neck or upper airway collapsibility in response to intravenous fluid loading. These possibilities remain to be tested in future studies. © 2014 Associated Professional Sleep Societies, LLC.

Acquisition system environmental effects study. [for capillary-screen propellant retention devices

NASA Technical Reports Server (NTRS)

1975-01-01

The effects of vibration, warm gas exposure, and feed system startup/shutdown fluid dynamics on capillary-screen propellant retention capabilities are quantified. The existing technology is extended to the point where quantitative conlusions in terms of design criteria may be drawn.

Fluid administration in severe sepsis and septic shock, patterns and outcomes: an analysis of a large national database.

PubMed

Marik, Paul E; Linde-Zwirble, Walter T; Bittner, Edward A; Sahatjian, Jennifer; Hansell, Douglas

2017-05-01

The optimal strategy of fluid resuscitation in the early hours of severe sepsis and septic shock is controversial, with both an aggressive and conservative approach being recommended. We used the 2013 Premier Hospital Discharge database to analyse the administration of fluids on the first ICU day, in 23,513 patients with severe sepsis and septic shock, who were admitted to an ICU from the emergency department. Day 1 fluid was grouped into categories 1 L wide, starting with 1-1.99 L up to ≥9 L, to examine the effect of day 1 fluids on patient mortality. We built binary response models for hospital mortality and the propensity for receiving more than 5 L of fluids on day 1, using patient age and acute conditions present on admission. Patients were grouped by the requirement for mechanical ventilation and the presence or absence of shock. We assessed trends in the difference between actual and expected mortality, in the low fluid range (1-5 L day 1 fluids) and the high fluid range (5 to ≥9 L day 1 fluids) categories, using weighted linear regression controlling for the effects of sample size and variation within the day 1 fluid category. Day 1 fluid administration averaged 4.4 L being lowest in the group with no mechanical ventilation and no shock (3.6 L) and highest (5.4 L) in the group receiving mechanical ventilation and in shock. The administration of day 1 fluids was remarkably consistent on the basis of hospital size, teaching status, rural/urban location, and region of the country. The hospital mortality in the entire cohort was 25.8%, with a mean ICU and hospital length of stay of 5.1 and 9.1 days, respectively. In the entire cohort, low volume resuscitation (1-4.99 L) was associated with a small but significant reduction in mortality, of -0.7% per litre (95% CI -1.0%, -0.4%; p = 0.02). However, in patients receiving high volume resuscitation (5 to ≥9 L), the mortality increased by 2.3% (95% CI 2.0, 2.5%; p = 0.0003) for

Effect of an oxygen plasma on the physical and chemical properties of several fluids for the liquid droplet radiator

NASA Technical Reports Server (NTRS)

Gulino, D. A.; Coles, C. E.

1986-01-01

The Liquid Droplet Radiator is one of several radiator systems currently under investigation by NASA Lewis Research Center. It involves the direct exposure of the radiator working fluid to the space environment. An area of concern is the potential harmful effects of the low-Earth-orbit atomic oxygen environment on the radiator working fluid. To address this issue, seven candidate fluids were exposed to an oxygen plasma environment in a laboratory plasma asher. The fluids studied included Dow Corning 705 Diffusion Pump Fluid, polymethylphenylsiloxane and polydimethlsiloxane, both of which are experimental fluids made by Dow Corning, Fomblin Z25, made by Montedison, and three fluids from the Krytox family of fluids, Krytox 143AB, 1502, and 16256, which are made by DuPont. The fluids were characterized by noting changes in visual appearance, physical state, mass, and infrared spectra. Of the fluids tested, the Fomblin and the three Krytoxes were the least affected by the oxygen plasma. The only effect noted was a change in mass, which was most likely due to an oxygen-catalyzed deploymerization of the fluid molecule.

A Viscoelastic Deadly Fluid in Carnivorous Pitcher Plants

NASA Astrophysics Data System (ADS)

Gaume, Laurence; Forterre, Yoel

2008-07-01

We study the rheology of the digestive fluid secreted by the carnivorous pitcher plants Nepenthes rafflesiana and its role in the mechanism of insects trapping. Using a combination of physical measurements (surface tension, wetting properties, extensional and shear rheometry), insects bioessays and high-speed video, we show that the digestive fluid of Nepenthes rafflesiana is a highly viscoelastic fluid and that this property is crucial for the retention of insect in its trap. Trapping efficiency is shown to remain strong even when the fluid is highly diluted by water, as long as the elastic relaxation time of the fluid is higher than the typical time scale of insect movements (large Deborah numbers).

The physical mechanisms of complete denture retention.

PubMed

Darvell, B W; Clark, R K

2000-09-09

The purpose of this article is to assist the practitioner to understand which factors are relevant to complete denture retention in the light of the current understanding of physics and materials science and thus to guide design. Atmospheric pressure, vacuum, adhesion, cohesion, surface tension, viscosity, base adaption, border seal, seating force and muscular control have all been cited at one time or another as major or contributory factors, but usually as an opinion without proper reference to fundamental principles. Although there has been a detailed analysis published, it seems appropriate that a restatement of the points in a collated form be made. In fact, denture retention is a dynamic issue dependent on the control of the flow of interposed fluid and thus its viscosity and film thickness, while the timescale of displacement loading affects the assessment. Surface tension forces at the periphery contribute to retention, but the most important concerns are good base adaptation and border seal. These must be achieved if full advantage is to be taken of the saliva flow-related effects.

Predictors of home healthcare nurse retention.

PubMed

Ellenbecker, Carol Hall; Porell, Frank W; Samia, Linda; Byleckie, James J; Milburn, Michael

2008-01-01

To examine the level of job satisfaction and test a theoretical model of the direct and indirect effects of job satisfaction, and individual nurse and agency characteristics, on intent to stay and retention for home healthcare nurses. A descriptive correlation study of home healthcare nurses in six New England states. Home healthcare nurse job satisfaction self-report data was collected with the HHNJS survey questionnaire & Retention Survey Questionnaire. Based on a structural equation model, job tenure and job satisfaction were the strongest predictors of nurse retention. Understanding the variables associated with home healthcare nurse retention can help agencies retain nurses in a time of severe nurse shortages and increased patient demand. Predicted nursing shortages and increasing demand have made the retention of experienced, qualified nursing staff essential to assure access to high-quality home healthcare services in the future.

ORTHODONTIC RETENTION. Studies of retention capacity, cost-effectiveness and long-term stability.

PubMed

Tynelius, Gudrun Edman

2014-01-01

gender had no significant influence on mandibular LII (Paper II, Figure 4 and Table 4). Paper III. The cost minimization analysis disclosed that although the three retention methods achieved clinically similar results, the associated societal costs differed. After two years of retention, the vacuum-formed retainer (VFR) in combination with a canine-to-canine retainer (CTC) was the least cost-effective retention appliance. Paper IV. After five years or more out of retention, the three retention methods had achieved equally favourable clinical results. Key conclusion and clinical implications. This study compared the short- and long-term outcomes of orthodontic retention by three different methods: a maxillary vacuum-formed retainer combined with a mandibular canine-to-canine retainer; a maxillary vacuum-formed retainer combined with stripping of the mandibular anterior teeth and a prefabricated positioner. All methods gave equally positive clinical results in both the short-term, i.e. after one and two years of retention, and in the long-term, five years or more post-retention. After two years of retention, the level of compliance affected the retention treatment result. However, no such effect was shown for body height, the severity of initial crowding or gender. Today, there is increasing emphasis on the importance of economic aspects of healthcare. Of the three methods evaluated in this study, the least cost-effective, after two years of retention, was a vacuum-formed retainer combined with a bonded canine-to-canine retainer. The clinical implication of this finding is that in patients meeting the inclusion criteria, interproximal stripping of the mandibular anterior teeth, or the use of a prefabricated positioner, are highly appropriate alternatives to a mandibular bonded canine-to-canine retainer. The overall conclusions are that there are a number of effective retention methods available and the clinician is not limited to routine use of a bonded mandibular canine

Fluid physico-chemical properties influence capture and diet in Nepenthes pitcher plants

PubMed Central

Bazile, Vincent; Le Moguédec, Gilles; Marshall, David J.; Gaume, Laurence

2015-01-01

Background and Aims Nepenthes pitcher plants have evolved modified leaves with slippery surfaces and enzymatic fluids that trap and digest prey, faeces and/or plant detritus. Although the fluid’s contribution to insect capture is recognized, the physico-chemical properties involved remain underexplored and may vary among species, influencing their diet type. This study investigates the contributions of acidity and viscoelasticity in the fluid’s capture efficiency of two ant and two fly species in four Nepenthes species with different nutrition strategies. Methods Four Nepenthes species were studied, namely N. rafflesiana, N. gracilis, N. hemsleyana and N. ampullaria. Fluid was collected from pitchers of varying ages from plants growing in the field and immediately transferred to glass vials, and individual ants (tribe Campotini, Fomicinae) and flies (Calliphora vomitoria and Drosophila melanogaster) were dropped in and observed for 5 min. Water-filled vials were used as controls. Survival and lifetime data were analysed using models applied to right-censored observations. Additional laboratory experiments were carried out in which C. vomitoria flies were immersed in pH-controlled aqueous solutions and observed for 5 min. Key Results Pitcher fluid differed among Nepenthes species as regards insect retention capacity and time-to-kill, with differences observed between prey types. Only the fluids of the reputedly insectivorous species were very acidic and/or viscoelastic and retained significantly more insects than the water controls. Viscoelastic fluids were fatal to flies and were able to trap the broadest diversity of insects. Younger viscoelastic fluids showed a better retention ability than older fluids, although with less rapid killing ability, suggesting that a chemical action follows a mechanical one. Insect retention increased exponentially with fluid viscoelasticity, and this happened more abruptly and at a lower threshold for flies compared with

Housing Retention in Single-Site Housing First for Chronically Homeless Individuals With Severe Alcohol Problems

PubMed Central

Malone, Daniel K.; Clifasefi, Seema L.

2013-01-01

Objectives. We studied housing retention and its predictors in the single-site Housing First model. Methods. Participants (n = 111) were chronically homeless people with severe alcohol problems who lived in a single-site Housing First program and participated in a larger nonrandomized controlled trial (2005–2008) conducted in Seattle, Washington. At baseline, participants responded to self-report questionnaires assessing demographic, illness burden, alcohol and other drug use, and psychiatric variables. Housing status was recorded over 2 years. Results. Participants were interested in housing, although a sizable minority did not believe they would be able to maintain abstinence-based housing. Only 23% of participants returned to homelessness during the 2-year follow-up. Commonly cited risk factors—alcohol and other drug use, illness burden, psychiatric symptoms, and homelessness history—did not predict resumed homelessness. Active drinkers were more likely to stay in this housing project than nondrinkers. Conclusions. We found that single-site Housing First programming fills a gap in housing options for chronically homeless people with severe alcohol problems. PMID:24148063

A Randomized, Double Crossover Study to Investigate the Influence of Saline Infusion on Sleep Apnea Severity in Men

PubMed Central

Yadollahi, Azadeh; Gabriel, Joseph M.; White, Laura H.; Taranto Montemurro, Luigi; Kasai, Takatoshi; Bradley, T. Douglas

2014-01-01

Study Objectives: Obstructive sleep apnea (OSA) is commoner in patients with fluid-retaining states than in those without fluid retention, in men than in women, and worsens with aging. In men, OSA severity is related to the amount of fluid shifting out of the legs overnight, but a cause-effect relationship is not established. Our objective was to test the hypothesis that mimicking fluid overload during sleep would increase severity of OSA more in older (≥ 40 years) than in younger men (< 40 years). Design: Randomized, single-blind, double crossover study. Setting: Research sleep laboratory. Patients or Participants: Seven older and 10 younger men with non-severe or no sleep apnea, matched for body mass index. Interventions: During the control arm, normal saline was infused to keep the vein open. During intervention, subjects received an intravenous bolus of normal saline (22 mL/kg body weight) after sleep onset while they were wearing compression stockings to prevent fluid accumulation in the legs. Measurements and Results: Compared to younger men, infusion of similar amounts of saline in older men caused a greater increase in neck circumference (P < 0.05) and in the AHI (32.2 ± 22.1 vs. 2.2 ± 7.1, P = 0.002). Conclusions: Older men are more susceptible to the adverse effects of intravenous fluid loading on obstructive sleep apnea severity than younger men. This may be due to age-related differences in the amount of fluid accumulating in the neck or upper airway collapsibility in response to intravenous fluid loading. These possibilities remain to be tested in future studies. Citation: Yadollahi A, Gabriel JM, White LH, Taranto Montemurro L, Kasai T, Bradley TD. A randomized, double crossover study to investigate the influence of saline infusion on sleep apnea severity in men. SLEEP 2014;37(10):1699-1705. PMID:25197812

Fluid physico-chemical properties influence capture and diet in Nepenthes pitcher plants.

PubMed

Bazile, Vincent; Le Moguédec, Gilles; Marshall, David J; Gaume, Laurence

2015-03-01

Nepenthes pitcher plants have evolved modified leaves with slippery surfaces and enzymatic fluids that trap and digest prey, faeces and/or plant detritus. Although the fluid's contribution to insect capture is recognized, the physico-chemical properties involved remain underexplored and may vary among species, influencing their diet type. This study investigates the contributions of acidity and viscoelasticity in the fluid's capture efficiency of two ant and two fly species in four Nepenthes species with different nutrition strategies. Four Nepenthes species were studied, namely N. rafflesiana, N. gracilis, N. hemsleyana and N. ampullaria. Fluid was collected from pitchers of varying ages from plants growing in the field and immediately transferred to glass vials, and individual ants (tribe Campotini, Fomicinae) and flies (Calliphora vomitoria and Drosophila melanogaster) were dropped in and observed for 5 min. Water-filled vials were used as controls. Survival and lifetime data were analysed using models applied to right-censored observations. Additional laboratory experiments were carried out in which C. vomitoria flies were immersed in pH-controlled aqueous solutions and observed for 5 min. Pitcher fluid differed among Nepenthes species as regards insect retention capacity and time-to-kill, with differences observed between prey types. Only the fluids of the reputedly insectivorous species were very acidic and/or viscoelastic and retained significantly more insects than the water controls. Viscoelastic fluids were fatal to flies and were able to trap the broadest diversity of insects. Younger viscoelastic fluids showed a better retention ability than older fluids, although with less rapid killing ability, suggesting that a chemical action follows a mechanical one. Insect retention increased exponentially with fluid viscoelasticity, and this happened more abruptly and at a lower threshold for flies compared with ants. Flies were more often retained if they

Predictors of Percutaneous Catheter Drainage (PCD) after Abdominal Paracentesis Drainage (APD) in Patients with Moderately Severe or Severe Acute Pancreatitis along with Fluid Collections

PubMed Central

Liu, Wei-hui; Wang, Tao; Yan, Hong-tao; Chen, Tao; Xu, Chuan; Ye, Ping; Zhang, Ning; Liu, Zheng-cai; Tang, Li-jun

2015-01-01

Aims Although we previously demonstrated abdominal paracentesis drainage (APD) preceding percutaneous catheter drainage (PCD) as the central step for treating patients with moderately severe (MSAP) or severe acute pancreatitis (SAP), the predictors leading to PCD after APD have not been studied. Methods Consecutive patients with MSAP or SAP were recruited between June 2011 and June 2013. As a step-up approach, all patients initially received medical management, later underwent ultrasound-guided APD before PCD, if necessary, followed by endoscopic necrosectomy through the path formed by PCD. APD primarily targeted fluid in the abdominal or pelvic cavities, whereas PCD aimed at (peri)pancreatic fluid. Results Of the 92 enrolled patients, 40 were managed with APD alone and 52 received PCD after APD (14 required necrosectomy after initial PCD). The overall mortality was 6.5%. Univariate analysis showed that among the 20 selected parameters, 13 factors significantly affected PCD intervention after APD. Multivariate analysis revealed that infected (peri)pancreatic collections (P = -0.001), maximum extent of necrosis of more than 30% of the pancreas (P = -0.024), size of the largest necrotic peri(pancreatic) collection (P = -0.007), and reduction of (peri)pancreatic fluid collections by <50% after APD (P = -0.008) were all independent predictors of PCD. Conclusions Infected (peri)pancreatic collections, a largest necrotic peri(pancreatic) collection of more than 100 ml, and reduction of (peri)pancreatic fluid collections by <50% after APD could effectively predict the need for PCD in the early course of the disease. PMID:25659143

Vectorization on the star computer of several numerical methods for a fluid flow problem

NASA Technical Reports Server (NTRS)

Lambiotte, J. J., Jr.; Howser, L. M.

1974-01-01

A reexamination of some numerical methods is considered in light of the new class of computers which use vector streaming to achieve high computation rates. A study has been made of the effect on the relative efficiency of several numerical methods applied to a particular fluid flow problem when they are implemented on a vector computer. The method of Brailovskaya, the alternating direction implicit method, a fully implicit method, and a new method called partial implicitization have been applied to the problem of determining the steady state solution of the two-dimensional flow of a viscous imcompressible fluid in a square cavity driven by a sliding wall. Results are obtained for three mesh sizes and a comparison is made of the methods for serial computation.

Clinically severe Epstein-Barr virus encephalitis with mild cerebrospinal fluid abnormalities in an immunocompetent adolescent: a case report.

PubMed

Engelmann, Ilka; Nasser, Hala; Belmiloudi, Soufien; Le Guern, Rémi; Dewilde, Anny; Vallée, Louis; Hober, Didier

2013-06-01

A 15-year-old boy developed Epstein-Barr virus (EBV) encephalitis, a rare complication of infectious mononucleosis. The severe clinical picture and the marked neuroimaging changes were in contrast with mild cerebrospinal fluid abnormalities: leukocyte count was normal and protein level was only slightly elevated. EBV DNA was detected in cerebrospinal fluid by polymerase chain reaction. Copyright © 2013 Elsevier Inc. All rights reserved.

Meningitis-retention syndrome. An unrecognized clinical condition.

PubMed

Sakakibara, Ryuji; Uchiyama, Tomoyuki; Liu, Zhi; Yamamoto, Tatsuya; Ito, Takashi; Uzawa, Akiyuki; Suenaga, Tadahiro; Kanai, Kazuaki; Awa, Yusuke; Sugiyama, Yoshiki; Hattori, Takamichi

2005-12-01

A combination of acute urinary retention and aseptic meningitis has not been well known. This combination can be referred to as meningitis-retention syndrome (MRS), when accompanied by no other abnormalities. To describe the results of a uro-neurological assessment in our patients with MRS. In three patients (two men, one woman; age, 34-68 years), we performed urodynamic studies and relevant imaging and neurophysiological tests, in addition to cerebrospinal fluid (CSF) examination. All three patients developed acute urinary retention along with headache, fever and stiff neck. None had obvious neurological abnormalities, other than a slightly brisk reflex in the lower extremities. One had previously experienced generalized erythematous eruptions, but none had pain, hypalgesia or skin eruptions in the sacral dermatomes suggestive of Elsberg syndrome (infectious sacral polyradiculitis; mostly genital herpes). Brain/spinal/lumbar plexus MRI scans and nerve conduction studies were normal. CSF examination showed mild mononuclear pleocytosis, increased protein content, and normal to mildly decreased glucose content in all patients; increased myelin basic protein suggestive of central nervous system demyelination in one; and increased viral titers in none. Urodynamic study revealed, during the voiding phase, an underactive detrusor in all patients and an unrelaxing sphincter in one. These clinical manifestations were ameliorated within 3 weeks. We reported three cases of MRS, a peculiar syndrome that could be regarded as a mild variant of acute disseminated encephalomyelitis (ADEM). Urinary retention might reflect acute shock phase of this disorder. Although MRS has a benign and self-remitting course, management of the acute urinary retention is necessary.

A Janus Mucoadhesive and Omniphobic Device for Gastrointestinal Retention.

PubMed

Lee, Young-Ah Lucy; Zhang, Shiyi; Lin, Jiaqi; Langer, Robert; Traverso, Giovanni

2016-05-01

A novel Janus device with omniphobic and mucoadhesive sides that exhibit the unique capacity for antifouling and extended gastrointestinal retention is fabricated. This system enables repulsion of the food and fluid stream by the luminal-facing omniphobic side and allows attachment to the gastrointestinal mucosa by the mucoadhesive side. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fluid overpressures and strength of the sedimentary upper crust

NASA Astrophysics Data System (ADS)

Suppe, John

2014-12-01

The classic crustal strength-depth profile based on rock mechanics predicts a brittle strength σ1 -σ3 = κ(ρbar gz -Pf) that increases linearly with depth as a consequence of [1] the intrinsic brittle pressure dependence κ plus [2] an assumption of hydrostatic pore-fluid pressure, Pf = ρwgz. Many deep borehole stress data agree with a critical state of failure of this form. In contrast, fluid pressures greater than hydrostatic ρbar gz >Pf >ρw gz are normally observed in clastic continental margins and shale-rich mountain belts. Therefore we explore the predicted shapes of strength-depth profiles using data from overpressured regions, especially those dominated by the widespread disequilibrium-compaction mechanism, in which fluid pressures are hydrostatic above the fluid-retention depth zFRD and overpressured below, increasing parallel to the lithostatic gradient ρbar gz . Both brittle crustal strength and frictional fault strength below the zFRD must be constant with depth because effective stress (ρbar gz -Pf) is constant, in contrast with the classic linearly increasing profile. Borehole stress and fluid-pressure measurements in several overpressured deforming continental margins agree with this constant-strength prediction, with the same pressure-dependence κ as the overlying hydrostatic strata. The role of zFRD in critical-taper wedge mechanics and jointing is illustrated. The constant-strength approximation is more appropriate for overpressured crust than classic linearly increasing models.

The effects of water replacement by oral rehydration fluids with or without betaine supplementation on performance, acid-base balance, and water retention of heat-stressed broiler chickens.

PubMed

Sayed, M A M; Downing, J

2011-01-01

Exposing broilers to a high temperature increases water and electrolyte K(+) and Na(+) excretion, which negatively affects the heat dissipation capacity and acid-base homeostasis, resulting in losses in growth performance. In this experiment, the efficacy of providing oral rehydration therapy and betaine on growth performance, acid-base balance, and water and electrolyte retention was evaluated. A total of 432 one-day-old broiler chicks (Cobb) were allocated to 72 metabolic cages and reared to 31 d of age under standard conditions. From 32 to 41 d of age, chicks were exposed to heat stress (ambient temperature, 32°C) and high RH (80 to 100% RH) for 9 h daily. The ameliorative effects of a 3 × 3 factorial array of treatments administered via drinking water were evaluated in 8 replicates of 6 chicks per cage for each treatment. Two oral rehydration therapy (ORT) fluids, based on either citrate or bicarbonate salts, were added to tap water. In addition, betaine was added to tap water at an inclusion rate of 0, 500, or 1,000 mg/L to complete the array of 9 liquid-based treatments. Growth performance was assessed at 32, 35, and 41 d of age. From 32 to 35 d of age, chicks receiving ORT fluids exhibited improved growth performance, water balance, and electrolyte (K(+), Na(+)) retention. In addition, the physiological response to stress was attenuated, as indicated by lower heterophil-to-lymphocyte ratios and blood glucose concentrations relative to the negative controls. The addition of betaine at an inclusion rate of 500 mg/L improved BW gain. From d 36 to 41, treatments did not significantly influence growth performance, which suggests that chicks receiving tap water were able to compensate and adapt to the heat-stress conditions. The results demonstrate that the beneficial effects of providing ORT fluids and 500 mg of betaine/L were observed only during the first 4 d of heat exposure. After this period, adaptation to the heat appears to occur, and none of the

Biomarkers for Severity of Spinal Cord Injury in the Cerebrospinal Fluid of Rats

PubMed Central

Lubieniecka, Joanna M.; Streijger, Femke; Lee, Jae H. T.; Stoynov, Nikolay; Liu, Jie; Mottus, Randy; Pfeifer, Tom; Kwon, Brian K.; Coorssen, Jens R.; Foster, Leonard J.; Grigliatti, Thomas A.; Tetzlaff, Wolfram

2011-01-01

One of the major challenges in management of spinal cord injury (SCI) is that the assessment of injury severity is often imprecise. Identification of reliable, easily quantifiable biomarkers that delineate the severity of the initial injury and that have prognostic value for the degree of functional recovery would significantly aid the clinician in the choice of potential treatments. To find such biomarkers we performed quantitative liquid chromatography-mass spectrometry (LC-MS/MS) analyses of cerebrospinal fluid (CSF) collected from rats 24 h after either a moderate or severe SCI. We identified a panel of 42 putative biomarkers of SCI, 10 of which represent potential biomarkers of SCI severity. Three of the candidate biomarkers, Ywhaz, Itih4, and Gpx3 were also validated by Western blot in a biological replicate of the injury. The putative biomarkers identified in this study may potentially be a valuable tool in the assessment of the extent of spinal cord damage. PMID:21559420

Safeguards Workforce Repatriation, Retention and Utilization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gallucci, Nicholas; Poe, Sarah

Brookhaven National Laboratory was tasked by NA-241 to assess the transition of former IAEA employees back to the United States, investigating the rate of retention and overall smoothness of the repatriation process among returning safeguards professionals. Upon conducting several phone interviews, study authors found that the repatriation process went smoothly for the vast majority and that workforce retention was high. However, several respondents expressed irritation over the minimal extent to which their safeguards expertise had been leveraged in their current positions. This sentiment was pervasive enough to prompt a follow-on study focusing on questions relating to the utilization rather thanmore » the retention of safeguards professionals. A second, web-based survey was conducted, soliciting responses from a larger sample pool. Results suggest that the safeguards workforce may be oversaturated, and that young professionals returning to the United States from Agency positions may soon encounter difficulties finding jobs in the field.« less

Computational fluid dynamics modelling of hydraulics and sedimentation in process reactors during aeration tank settling.

PubMed

Jensen, M D; Ingildsen, P; Rasmussen, M R; Laursen, J

2006-01-01

Aeration tank settling is a control method allowing settling in the process tank during high hydraulic load. The control method is patented. Aeration tank settling has been applied in several waste water treatment plants using the present design of the process tanks. Some process tank designs have shown to be more effective than others. To improve the design of less effective plants, computational fluid dynamics (CFD) modelling of hydraulics and sedimentation has been applied. This paper discusses the results at one particular plant experiencing problems with partly short-circuiting of the inlet and outlet causing a disruption of the sludge blanket at the outlet and thereby reducing the retention of sludge in the process tank. The model has allowed us to establish a clear picture of the problems arising at the plant during aeration tank settling. Secondly, several process tank design changes have been suggested and tested by means of computational fluid dynamics modelling. The most promising design changes have been found and reported.

A study of the effects of long-term exposure to fuels and fluids on the behavior of advanced composite materials

NASA Technical Reports Server (NTRS)

Tanimoto, E. Y.

1981-01-01

The periodic testing and evaluation of graphite/epoxy and Kevlar/epoxy material systems after subjecting test specimens to prolonged exposure to several laboratory-controlled environments deemed typical of normal aircraft operations is discussed. It is noted that specimen immersion in water or water-based fluids resulted in the greatest effect on the mechanical properties tested. Also, the environmental fluids showed a tendency to affect Kevlar/epoxy systems at an earlier exposure period than the graphite/epoxy systems. Results also indicate mechanical property strength retention generally being lower for the Kevlar/epoxy systems when compared to the corresponding graphite/epoxy systems in similar environments, after prolonged exposure.

Fiber length and orientation prevent migration in fluid filters

NASA Technical Reports Server (NTRS)

Reiman, P. A.

1966-01-01

Stainless steel fiber web filter resists fiber migration which causes contamination of filtered fluids. This filter is capable of holding five times more particulate matter before arbitrary cutoff pressure drop and shows excellent retention in fuel flow at high rates.

Intracochlear drug injections through the round window membrane: Measures to improve drug retention

PubMed Central

Plontke, Stefan K.; Hartsock, Jared J.; Gill, Ruth M.; Salt, Alec N.

2016-01-01

The goal of this study was to develop appropriate methodology to apply drugs quantitatively to perilymph of the ear. Intratympanic applications of drugs to the inner ear often result in variable drug levels in perilymph and can only be used for molecules that readily permeate the round window (RW) membrane. Direct intracochlear and intralabyrinthine application procedures for drugs, genes or cell-based therapies by-pass the tight boundaries at the round window, oval window, otic capsule and the blood-labyrinth barrier. However, perforations can release inner ear pressure, allowing cerebrospinal fluid to enter through the cochlear aqueduct, displacing the injected drug solution into the middle ear. Two markers, fluorescein or fluorescein isothiocyanate (FITC)-labeled dextran, were used to quantify how much of an injected substance was retained in cochlear perilymph following an intracochlear injection. We evaluated whether procedures to mitigate fluid leaks improved marker retention in perilymph. Almost all procedures to reduce volume efflux, including the use of gel for internal sealing and glue for external sealing of the injection site, resulted in improved retention of the marker in perilymph. Adhesive on the RW membrane effectively prevented leaks but also influenced fluid exchange between CSF and perilymph. We conclude that drugs can be delivered to the ear in a consistent, quantitative manner using intracochlear injections if care is taken to control the fluid leaks that result from cochlear perforation. PMID:26905306

The Role of Student Characteristics in Predicting Retention in Online Courses

ERIC Educational Resources Information Center

Cochran, Justin D.; Campbell, Stacy M.; Baker, Hope M.; Leeds, Elke M.

2014-01-01

Given the continued issue of student retention for online classes, past research has suggested several "retention strategies" focused on engaging students as a way to reduce their withdrawal rate from these classes. However, a recent study testing the effects of these strategies on retention in online undergraduate business courses…

Retention-Oriented Curricular Design

ERIC Educational Resources Information Center

Milanovic, Ivana; Eppes, Tom A.; Girouard, Janice; Townsend, Lee

2010-01-01

This paper presents a retention-oriented approach to the educational value stream within the STEM undergraduate area. Faced with several strategic challenges and opportunities, a Flex Advantage Plan was developed to enhance the undergraduate engineering technology programs and better utilize the curricular flexibilities inherent in the current…

Integrated fountain effect pump device for fluid management at low gravity

NASA Astrophysics Data System (ADS)

Yuan, S. W. K.; Frank, D. J.

1988-02-01

To transfer He II in space, the supply tank must be drained at low gravity. Conventional capillary devices such as the gallery system make use of the capillary retention capability of the screens for fluid management. Liquid helium is collected into gallery channels and then conveyed to the downstream fountain effect pump (FEP) or mechanical pump. In this Paper, a new fluid management device is proposed. The screens along the gallery channels are replaced by porous plugs which are responsible for both the fluid retention and pumping (by mechanical effect) of He II. No downstream pump is needed. The plugs in contact with liquid helium on both sides act as FEPs, and plugs exposed to vapour on one side behave as vapour-liquid phase separators (VLPSs). The total net transfer rate of He II into the receiving tank is the mass flow rate through the FEP minus the liquid loss from the VLPS plugs. The performance of the integrated FEP device (IFD) was analysed. The possibility of liquid breakthrough in the IFD was studied. The IFD is a very promising system for the fluid management of He II at low gravity.

Minoxidil for severe hypertension after failure of other hypotensive drugs.

PubMed Central

Devine, B L; Fife, R; Trust, P M

1977-01-01

Forty-four patients with severe hypertension who were resistant to treatment with more conventional hypotensive drugs or could not tolerate the side effects were treated with minoxidil, a potent peripheral vasodilator. A beta-blocking drug and a diuretic were used routinely to control, respectively, the tachycardia and fluid retention caused by minoxidil. During treatment the outpatient supine blood pressure fell from a mean of 221/134 mm Hg to 162/98 mm Hg. Eleven patients required additional or alternative hypotensive agents before blood pressure was adequately controlled. Side effects were minor, although the invariable hirsuties caused by minoxidil was unacceptable to three women. The possibility of cardiotoxic effects, raised by early studies in dogs, has not been excluded, and therefore this drug should be used only in patients with severe hypertension. In such patients minoxidil appears to be most effective. PMID:902045

Association of Fluid Resuscitation Initiation Within 30 Minutes of Severe Sepsis and Septic Shock Recognition With Reduced Mortality and Length of Stay.

PubMed

Leisman, Daniel; Wie, Benjamin; Doerfler, Martin; Bianculli, Andrea; Ward, Mary Frances; Akerman, Meredith; D'Angelo, John K; Zemmel D'Amore, Jason A

2016-09-01

We evaluate the association of intravenous fluid resuscitation initiation within 30 minutes of severe sepsis or septic shock identification in the emergency department (ED) with inhospital mortality and hospital length of stay. We also compare intravenous fluid resuscitation initiated at various times from severe sepsis or septic shock identification's association with the same outcomes. This was a review of a prospective, observational cohort of all ED severe sepsis or septic shock patients during 13 months, captured in a performance improvement database at a single, urban, tertiary care facility (90,000 ED visits/year). The primary exposure was initiation of a crystalloid bolus at 30 mL/kg within 30 minutes of severe sepsis or septic shock identification. Secondary analysis compared intravenous fluid initiated within 30, 31 to 60, or 61 to 180 minutes, or when intravenous fluid resuscitation was initiated at greater than 180 minutes or not provided. Of 1,866 subjects, 53.6% were men, 72.5% were white, mean age was 72 years (SD 16.6 years), and mean initial lactate level was 2.8 mmol/L. Eighty-six percent of subjects were administered intravenous antibiotics within 180 minutes; 1,193 (64%) had intravenous fluid initiated within 30 minutes. Mortality was lower in the within 30 minutes group (159 [13.3%] versus 123 [18.3%]; 95% confidence interval [CI] 1.4% to 8.5%), as was median hospital length of stay (6 days [95% CI 6 to 7] versus 7 days [95% CI 7 to 8]). In multivariate regression that included adjustment for age, lactate, hypotension, acute organ dysfunction, and Emergency Severity Index score, intravenous fluid within 30 minutes was associated with lower mortality (odds ratio 0.63; 95% CI 0.46 to 0.86) and 12% shorter length of stay (hazard ratio=1.14; 95% CI 1.02 to 1.27). In secondary analysis, mortality increased with later intravenous fluid resuscitation initiation: 13.3% (≤30 minutes) versus 16.0% (31 to 60 minutes) versus 16.9% (61 to 180 minutes

A Binomial Modeling Approach for Upscaling Colloid Transport Under Unfavorable Attachment Conditions: Emergent Prediction of Nonmonotonic Retention Profiles

NASA Astrophysics Data System (ADS)

Hilpert, Markus; Johnson, William P.

2018-01-01

We used a recently developed simple mathematical network model to upscale pore-scale colloid transport information determined under unfavorable attachment conditions. Classical log-linear and nonmonotonic retention profiles, both well-reported under favorable and unfavorable attachment conditions, respectively, emerged from our upscaling. The primary attribute of the network is colloid transfer between bulk pore fluid, the near-surface fluid domain (NSFD), and attachment (treated as irreversible). The network model accounts for colloid transfer to the NSFD of downgradient grains and for reentrainment to bulk pore fluid via diffusion or via expulsion at rear flow stagnation zones (RFSZs). The model describes colloid transport by a sequence of random trials in a one-dimensional (1-D) network of Happel cells, which contain a grain and a pore. Using combinatorial analysis that capitalizes on the binomial coefficient, we derived from the pore-scale information the theoretical residence time distribution of colloids in the network. The transition from log-linear to nonmonotonic retention profiles occurs when the conditions underlying classical filtration theory are not fulfilled, i.e., when an NSFD colloid population is maintained. Then, nonmonotonic retention profiles result potentially both for attached and NSFD colloids. The concentration maxima shift downgradient depending on specific parameter choice. The concentration maxima were also shown to shift downgradient temporally (with continued elution) under conditions where attachment is negligible, explaining experimentally observed downgradient transport of retained concentration maxima of adhesion-deficient bacteria. For the case of zero reentrainment, we develop closed-form, analytical expressions for the shape, and the maximum of the colloid retention profile.

FLUID SELECTING APPARATUS

DOEpatents

Stinson, W.J.

1958-09-16

A valve designed to selectively sample fluids from a number of sources is described. The valve comprises a rotatable operating lever connected through a bellows seal to a rotatable assembly containing a needle valve, bearings, and a rotational lock. The needle valve is connected through a flexible tube to the sample fluid outlet. By rotating the lever the needle valve is placed over . one of several fluid sources and locked in position so that the fluid is traasferred through the flexible tubing and outlet to a remote sampling system. The fluids from the nonselected sources are exhausted to a waste line. This valve constitutes a simple, dependable means of selecting a sample from one of several scurces.

RETENTION OF HALOCARBONS ON A HEXAFLUOROPROPYLENE EPOXIDE-MODIFIED GRAPHITIZED CARBON BLACK - IV. PROPANE- BASED COMPOUNDS

EPA Science Inventory

The retention characteristics of 25 propane-based bromofluorocarbon, chlorocarbon, chlorofluorocarbon, and fluorocarbon fluids have been studied as a function of temperature on a stationary phase consisting of a 5% (m/m) coating of a low-molecular-mass polymer of hexafluoropropyl...

The effect of sitting and calf activity on leg fluid and snoring.

PubMed

Singh, Bhajan; Yadollahi, Azadeh; Lyons, Owen; Alshaer, Hisham; Bradley, T Douglas

2017-06-01

Prolonged sitting may promote leg fluid retention that redistributes to the neck during sleep and contributes to snoring. This could be attenuated by calf activity while sitting. In 16 healthy non-obese subjects we measured leg fluid volume (LFV) below the knees using bioelectrical impedance while sitting for 4h, snoring using a portable BresoDx™ device, and Mallampati grade. Using a double cross-over study design, subjects were randomized to one of two arms and crossed-over one week later: control arm - no calf exercise while sitting; intervention arm - calf contraction against a pedal resistance while sitting. The effects of sitting±calf activity on LFV and snoring were compared. We found that LFV increased by 216±101.0ml (p<0.0001) after sitting. Calf activity while sitting attenuated LFV by 53.8ml (p<0.0001) and, in all five subjects with severe upper airway narrowing (Mallampati grade IV), reduced snoring duration (from 357±132.9 to 116.2±72.1s/h, p=0.02) suggesting reduced overnight rostral fluid shift to the neck. Copyright © 2017 Elsevier B.V. All rights reserved.

Specialized moisture retention eyewear for evaporative dry eye.

PubMed

Waduthantri, Samanthila; Tan, Chien Hua; Fong, Yee Wei; Tong, Louis

2015-05-01

To evaluate the suitablity of commercially available moisture retention eyewear for treating evaporative dry eye. Eleven patients with evaporative dry eyes were prescibed moisture retention eyewear for 3 months in addition to regular lubricant eye drops. Frequency and severity of dry eye symptoms, corneal fluorescein staining and tear break up time (TBUT) were evaluated at baseline and 3-month post-treatment. Main outcome measure was global symptom score (based on severity and frequency of dry eye symptoms on a visual analog scale) and secondary outcomes were changes in sectoral corneal fluorescein staining and tear break up time (TBUT) from pre-treatment level. There was a significant improvement in dry eye symptoms after using moisture retention eyewear for 3 months (p < 0.05). Corneal fluorescein staining in all five zones of the cornea in both eyes improved significantly (p < 0.05). There was no significant improvement in TBUT. Patients used ocular lubricants less frequently (p < 0.05) compared to the commencement of the study. Patients found moisture retention eyewear to be useful in relieving dry eye symptoms in windy, air-conditioned environments or when doing vision-related daily tasks. This study shows that moisture retention eyewear might be a valuable adjunct in management of evaporative dry eye and this new design of commercially available eyewear could have a good acceptability rate.

Computational Fluid Dynamics Simulation of Transport and Retention of Nanoparticle in Saturated Sand Filters

EPA Science Inventory

Experimental and computational investigation of the transport parameters of nano particles flowing through porous media has been made. The objective of this work was to develop a simulation capability applicable to the transport and retention of nanoparticles (NPs) in saturated p...

Deuterium retention in tungsten in dependence of the surface conditions

NASA Astrophysics Data System (ADS)

Ogorodnikova, O. V.; Roth, J.; Mayer, M.

2003-03-01

The paper reviews hydrogen isotope retention and migration in tungsten (W). Due to a large scatter of the deuterium (D) retention database, new measurements of ion-driven D retention in polycrystalline W foil have been performed to clarify the mechanism of hydrogen isotope inventory in W. Deuterium retention has been investigated as a function of ion fluence, implantation temperature, incident energy and surface conditions. Special attention has been given on the investigation of D retention in thin films of tungsten carbide and tungsten oxide which can be formed on W surface in a fusion device. Such kinds of films increase the D retention in W. Several points are reviewed: (i) inventory in pure W, (ii) inventory in W pre-implanted by carbon ions and (iii) inventory in tungsten oxide.

Influence of Two-Phase Thermocapillary Flow on Cryogenic Liquid Retention in Microscopic Pores

NASA Technical Reports Server (NTRS)

Schmidt, G. R.; Nadarajah, A.; Chung, T. J.; Karr, G. R.

1994-01-01

Previous experiments indicate that the bubble point pressure of spacecraft liquid hydrogen acquisition devices is reduced substantially when the ullage is pressurized with heated hydrogen vapor. The objective is to determine whether the two-phase thermocapillary convection arising from thermodynamic non-equilibrium along the porous surfaces of such devices could lead to this observed degradation in retention performance. We also examine why retention capability appears to be unaffected by pressurization with heated helium or direct heating through the porous structure. Computational assessments based on coupled solution of the flowfield and liquid free surface indicate that for highly wetting fluids in small pores, dynamic pressure and vapor recoil dictate surface morphology and drive meniscus deformation. With superheating, the two terms exert the same influence on curvature and promote mechanical equilibrium, but with subcooling, the pressure distribution produces a suction about the pore center-line that degrades retention. This result points to thermocapillary-induced deformation arising from condensation as the cause for retention loss. It also indicates that increasing the level of non-equilibrium by reducing accommodation coefficient restricts deformation and explains why retention failure does not occur with direct screen heating or helium pressurization.

Joule-Thomson inversion curves and related coefficients for several simple fluids

NASA Technical Reports Server (NTRS)

Hendricks, R. C.; Peller, I. C.; Baron, A. K.

1972-01-01

The equations of state (PVT relations) for methane, oxygen, argon, carbon dioxide, carbon monoxide, neon, hydrogen, and helium were used to establish Joule-Thomson inversion curves for each fluid. The principle of corresponding states was applied to the inversion curves, and a generalized inversion curve for fluids with small acentric factors was developed. The quantum fluids (neon, hydrogen, and helium) were excluded from the generalization, but available data for the fluids xenon and krypton were included. The critical isenthalpic Joule-Thomson coefficient mu sub c was determined; and a simplified approximation mu sub c approximates T sub c divided by 6P sub c was found adequate, where T sub c and P sub c are the temperature and pressure at the thermodynamic critical point. The maximum inversion temperatures were obtained from the second virial coefficient (maximum (B/T)).

Autoshaping induces ethanol drinking in nondeprived rats: evidence of long-term retention but no induction of ethanol preference.

PubMed

Tomie, Arthur; Kuo, Teresa; Apor, Khristine R; Salomon, Kimberly E; Pohorecky, Larissa A

2004-04-01

The effects of autoshaping procedures (paired vs. random) and sipper fluid (ethanol vs. water) on sipper-directed drinking were evaluated in male Long-Evans rats maintained with free access to food and water. For the paired/ethanol group (n=16), autoshaping procedures consisted of presenting the ethanol sipper (containing 0% to 28% unsweetened ethanol) conditioned stimulus (CS) followed by the response-independent presentation of food unconditioned stimulus (US). The random/ethanol group (n=8) received the sipper CS and food US randomly with respect to one another. The paired/water group (n=8) received only water in the sipper CS. The paired/ethanol group showed higher grams per kilogram ethanol intake than the random/ethanol group did at ethanol concentrations of 8% to 28%. The paired/ethanol group showed higher sipper CS-directed milliliter fluid consumption than the paired/water group did at ethanol concentrations of 1% to 6%, and 15%, 16%, 18%, and 20%. Following a 42-day retention interval, the paired/ethanol group showed superior retention of CS-directed drinking of 18% ethanol, relative to the random/ethanol group, and superior retention of CS-directed milliliter fluid drinking relative to the paired/water group. When tested for home cage ethanol preference using limited access two-bottle (28% ethanol vs. water) procedures, the paired/ethanol and random/ethanol groups did not differ on any drinking measures.

Institutionalization of a Retention Model

NASA Astrophysics Data System (ADS)

Davis, E. J.; Campbell, A.

2006-05-01

Bowie State University and NASA Goddard Space Flight Center have, for the past 10 years, worked diligently together to enhance the science, mathematics, engineering and technology (SMET) domain. Efforts made, because of a Model Institutions for Excellence (MIE) Award, have changed the landscape of the SMET domain by increasing the retention and graduation rates, the number of students entering graduate and professional schools, and the number of students entering SMET related careers for minorities and women. Several initiatives a Scholarship Program, PRISEM Tutoring Center, Safety-net Program, Research emphasis, Focused Mentoring, a Summer Academy for accepted incoming students, a Bridge Program for students needing assistance being admitted to the University, the RISE Program and the Bowie State Satellite Operations and Control Center (BSOCC) provide the nurturing, mentoring, and opportunities for our students. As a result of efforts made, the retention rate has increase to approximately 80%, the graduation rate has increased 40%, and 85% of the SMET students are now interested or entering graduate and professional schools. Successes that have been documented by various assessment activities have led to the institutionalization of the Retention Model of the MIE Initiative. It is anticipated that University-wide application of the retention model will prove the incentives necessary to obtain similar results as the MIE Initiative.

PAR-2 expression in the gingival crevicular fluid reflects chronic periodontitis severity.

PubMed

Fukushima, Henrique; Alves, Vanessa Tubero Euzebio; Carvalho, Verônica Franco de; Ambrósio, Lucas Macedo Batitucci; Eichler, Rosangela Aparecida Dos Santos; Carvalho, Maria Helena Catelli de; Saraiva, Luciana; Holzhausen, Marinella

2017-01-26

Recent studies investigating protease-activated receptor type 2 (PAR-2) suggest an association between the receptor and periodontal inflammation. It is known that gingipain, a bacterial protease secreted by the important periodontopathogen Porphyromonas gingivalis can activate PAR-2. Previous studies by our group found that PAR-2 is overexpressed in the gingival crevicular fluid (GCF) of patients with moderate chronic periodontitis (MP). The present study aimed at evaluating whether PAR-2 expression is associated with chronic periodontitis severity. GCF samples and clinical parameters, including plaque and bleeding on probing indices, probing pocket depth and clinical attachment level, were collected from the control group (n = 19) at baseline, and from MP patients (n = 19) and severe chronic periodontitis (SP) (n = 19) patients before and 6 weeks after periodontal non-surgical treatment. PAR-2 and gingipain messenger RNA (mRNA) in the GCF of 4 periodontal sites per patient were evaluated by Reverse Transcription Polymerase Chain Reaction (RT-qPCR). PAR-2 and gingipain expressions were greater in periodontitis patients than in control group patients. In addition, the SP group presented increased PAR-2 and gingipain mRNA levels, compared with the MP group. Furthermore, periodontal treatment significantly reduced (p <0.05) PAR-2 expression in patients with periodontitis. In conclusion, PAR-2 is associated with chronic periodontitis severity and with gingipain levels in the periodontal pocket, thus suggesting that PAR-2 expression in the GCF reflects the severity of destruction during periodontal infection.

Transdermal Scopolamine and Acute Postoperative Urinary Retention in Pelvic Reconstructive Surgery.

PubMed

Propst, Katie; OʼSullivan, David M; Tulikangas, Paul K

2016-01-01

To evaluate the relationship between perioperative use of transdermal scopolamine and the rate of urinary retention after stress urinary incontinence and pelvic organ prolapse procedures in women. This is a retrospective, cohort study; the primary outcome is the rate of acute postoperative urinary retention. Study candidates were adult female patients who underwent pelvic reconstructive surgery at a tertiary care center. Subjects were excluded if preoperative postvoid residual urine volume was greater than 150 mL, preoperative urodynamic testing was not performed, or if a postoperative trial of void was not performed. Subjects were grouped based on preoperative use of transdermal scopolamine. Patients were selected consecutively until 138 subjects per group was reached. Differences in rates of acute postoperative urinary retention were evaluated using a chi-square test. Group demographics were evaluated using t tests and χ tests. Two hundred seventy-six subjects were included in the analysis, 138 received a transdermal scopolamine patch in the perioperative period and 138 did not. The overall rate of acute postoperative urinary retention was 25.3%. There was no significant difference in the rate of acute postoperative urinary retention between the study groups (scopolamine, 26.8%; no scopolamine, 23.9%; P = 0.580). Demographics of the 2 groups were compared; patients who received scopolamine patch were younger (P = 0.001), received a greater amount of intravenous fluids (P = 0.007), and underwent a greater percentage of incontinence procedures (P = 0.048). Otherwise, there were no differences between the groups. Transdermal scopolamine is not a risk factor for acute postoperative urinary retention after pelvic reconstructive procedures.

Disregarded Effect of Biological Fluids in siRNA Delivery: Human Ascites Fluid Severely Restricts Cellular Uptake of Nanoparticles.

PubMed

Dakwar, George R; Braeckmans, Kevin; Demeester, Joseph; Ceelen, Wim; De Smedt, Stefaan C; Remaut, Katrien

2015-11-04

Small interfering RNA (siRNA) offers a great potential for the treatment of various diseases and disorders. Nevertheless, inefficient in vivo siRNA delivery hampers its translation into the clinic. While numerous successful in vitro siRNA delivery stories exist in reduced-protein conditions, most studies so far overlook the influence of the biological fluids present in the in vivo environment. In this study, we compared the transfection efficiency of liposomal formulations in Opti-MEM (low protein content, routinely used for in vitro screening) and human undiluted ascites fluid obtained from a peritoneal carcinomatosis patient (high protein content, representing the in vivo situation). In Opti-MEM, all formulations are biologically active. In ascites fluid, however, the biological activity of all lipoplexes is lost except for lipofectamine RNAiMAX. The drop in transfection efficiency was not correlated to the physicochemical properties of the nanoparticles, such as premature siRNA release and aggregation of the nanoparticles in the human ascites fluid. Remarkably, however, all of the formulations except for lipofectamine RNAiMAX lost their ability to be taken up by cells following incubation in ascites fluid. To take into account the possible effects of a protein corona formed around the nanoparticles, we recommend always using undiluted biological fluids for the in vitro optimization of nanosized siRNA formulations next to conventional screening in low-protein content media. This should tighten the gap between in vitro and in vivo performance of nanoparticles and ensure the optimal selection of nanoparticles for further in vivo studies.

Atomistic Modeling of the Fluid-Solid Interface in Simple Fluids

NASA Astrophysics Data System (ADS)

Hadjiconstantinou, Nicolas; Wang, Gerald

2017-11-01

Fluids can exhibit pronounced structuring effects near a solid boundary, typically manifested in a layered structure that has been extensively shown to directly affect transport across the interface. We present and discuss several results from molecular-mechanical modeling and molecular-dynamics (MD) simulations aimed at characterizing the structure of the first fluid layer directly adjacent to the solid. We identify a new dimensionless group - termed the Wall number - which characterizes the degree of fluid layering, by comparing the competing effects of wall-fluid interaction and thermal energy. We find that in the layering regime, several key features of the first layer layer - including its distance from the solid, its width, and its areal density - can be described using mean-field-energy arguments, as well as asymptotic analysis of the Nernst-Planck equation. For dense fluids, the areal density and the width of the first layer can be related to the bulk fluid density using a simple scaling relation. MD simulations show that these results are broadly applicable and robust to the presence of a second confining solid boundary, different choices of wall structure and thermalization, strengths of fluid-solid interaction, and wall geometries.

The effect of fluid overload on sleep apnoea severity in haemodialysis patients.

PubMed

Lyons, Owen D; Inami, Toru; Perger, Elisa; Yadollahi, Azadeh; Chan, Christopher T; Bradley, T Douglas

2017-04-01

As in heart failure, obstructive and central sleep apnoea (OSA and CSA, respectively) are common in end-stage renal disease. Fluid overload characterises end-stage renal disease and heart failure, and in heart failure plays a role in the pathogenesis of OSA and CSA. We postulated that in end-stage renal disease patients, those with sleep apnoea would have greater fluid volume overload than those without.End-stage renal disease patients on thrice-weekly haemodialysis underwent overnight polysomnography on a nondialysis day to determine their apnoea-hypopnoea index (AHI). Extracellular fluid volume of the total body, neck, thorax and right leg were measured using bioelectrical impedance.28 patients had an AHI ≥15 (sleep apnoea group; OSA:CSA 21:7) and 12 had an AHI <15 (no sleep apnoea group). Total body extracellular fluid volume was 2.6 L greater in the sleep apnoea group than in the no sleep apnoea group (p=0.006). Neck, thorax, and leg fluid volumes were also greater in the sleep apnoea than the no sleep apnoea group (p<0.05), despite no difference in body mass index (p=0.165).These findings support a role for fluid overload in the pathogenesis of both OSA and CSA in end-stage renal disease. Copyright ©ERS 2017.

The Role of Environmental Forcing in Controlling Water Retention Gyres in Subsystems of Narragansett Bay

NASA Astrophysics Data System (ADS)

Balt, C.; Kincaid, C. R.; Ullman, D. S.

2010-12-01

Greenwich Bay and the Providence River represent two subsystems of the Narragansett Bay (RI) estuary with chronic water quality problems. Both underway and moored Acoustic Doppler Current Profiler (ADCP) observations have shown the presence of large-scale, subtidal gyres within these subsystems. Prior numerical models of Narragansett Bay, developed using the Regional Ocean Modeling System (ROMS), indicate that prevailing summer sea breeze conditions are favorable to the evolution of stable circulation gyres, which increase retention times within each subsystem. Fluid dynamics laboratory models of the Providence River, conducted in the Geophysical Fluid Dynamics Laboratory of the Research School of Earth Sciences (Australian National University), reproduce gyres that match first order features of the ADCP data. These laboratory models also reveal details of small-scale eddies along the edges of the retention gyre. We report results from spatially and temporally detailed current meter deployments (using SeaHorse Tilt Current Meters) in both subsystems, which reveal details on the growth and decay of gyres under various spring-summer forcing conditions. In particular, current meters were deployed during the severe flooding events in the Narragansett Bay watershed during March, 2010. A combination of current meter data and high-resolution ROMS modeling is used to show how gyres effectively limit subtidal exchange from the Providence River and Greenwich Bay and to understand the forcing conditions that favor efficient flushing. The residence times of stable gyres within these regions can be an order of magnitude larger than values predicted by fraction of water methods. ROMS modeling is employed to characterize gyre energy, stability, and flushing rates for a wide range of seasonal, wind and runoff scenarios.

In-vessel melt retention as a severe accident management strategy for the Loviisa Nuclear Power Plant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kymaelaeinen, O.; Tuomisto, H.; Theofanous, T.G.

1997-02-01

The concept of lower head coolability and in-vessel retention of corium has been approved as a basic element of the severe accident management strategy for IVO`s Loviisa Plant (VVER-440) in Finland. The selected approach takes advantage of the unique features of the plant such as low power density, reactor pressure vessel without penetrations at the bottom and ice-condenser containment which ensures flooded cavity in all risk significant sequences. The thermal analyses, which are supported by experimental program, demonstrate that in Loviisa the molten corium on the lower head of the reactor vessel is coolable externally with wide margins. This papermore » summarizes the approach and the plant modifications being implemented. During the approval process some technical concerns were raised, particularly with regard to thermal loadings caused by contact of cool cavity water and hot corium with the reactor vessel. Resolution of these concerns is also discussed.« less

The reliability of the physical examination to guide fluid therapy in adults with severe falciparum malaria: an observational study.

PubMed

Hanson, Josh; Lam, Sophia W K; Alam, Shamsul; Pattnaik, Rajyabardhan; Mahanta, Kishore C; Uddin Hasan, Mahatab; Mohanty, Sanjib; Mishra, Saroj; Cohen, Sophie; Day, Nicholas; White, Nicholas; Dondorp, Arjen

2013-10-01

Adults with severe malaria frequently require intravenous fluid therapy to restore their circulating volume. However, fluid must be delivered judiciously as both under- and over-hydration increase the risk of complications and, potentially, death. As most patients will be cared for in a resource-poor setting, management guidelines necessarily recommend that physical examination should guide fluid resuscitation. However, the reliability of this strategy is uncertain. To determine the ability of physical examination to identify hypovolaemia, volume responsiveness, and pulmonary oedema, clinical signs and invasive measures of volume status were collected independently during an observational study of 28 adults with severe malaria. The physical examination defined volume status poorly. Jugular venous pressure (JVP) did not correlate with intravascular volume as determined by global end diastolic volume index (GEDVI; r(s) = 0.07, p = 0.19), neither did dry mucous membranes (p = 0.85), or dry axillae (p = 0.09). GEDVI was actually higher in patients with decreased tissue turgor (p < 0.001). Poor capillary return correlated with GEDVI, but was present infrequently (7% of observations) and, therefore, insensitive. Mean arterial pressure (MAP) correlated with GEDVI (rs = 0.16, p = 0.002), but even before resuscitation patients with a low GEDVI had a preserved MAP. Anuria on admission was unrelated to GEDVI and although liberal fluid resuscitation led to a median hourly urine output of 100 ml in 19 patients who were not anuric on admission, four (21%) developed clinical pulmonary oedema subsequently. MAP was unrelated to volume responsiveness (p = 0.71), while a low JVP, dry mucous membranes, dry axillae, increased tissue turgor, prolonged capillary refill, and tachycardia all had a positive predictive value for volume responsiveness of ≤50%. Extravascular lung water ≥11 ml/kg indicating pulmonary oedema was present on 99 of the 353 times that it was assessed during the

An Experimental Study on the Impact of Different-frequency Elastic Waves on Water Retention Curve

NASA Astrophysics Data System (ADS)

Deng, J. H.; Dai, J. Y.; Lee, J. W.; Lo, W. C.

2017-12-01

ABSTEACTOver the past few decades, theoretical and experimental studies on the connection between elastic wave attributes and the physical properties of a fluid-bearing porous medium have attracted the attention of many scholars in fields of porous medium flow and hydrogeology. It has been previously determined that the transmission of elastic waves in a porous medium containing two immiscible fluids will have an effect on the water retention curve, but it has not been found that the water retention curve will be affected by the frequency of elastic vibration waves or whether the effect on the soil is temporary or permanent. This research is based on a sand box test in which the soil is divided into three layers (a lower, middle, and upper layer). In this case, we discuss different impacts on the water retention curve during the drying process under sound waves (elastic waves) subject to three frequencies (150Hz, 300Hz, and 450Hz), respectively. The change in the water retention curve before and after the effect is then discussed. In addition, how sound waves affect the water retention curve at different depths is also observed. According to the experimental results, we discover that sound waves can cause soil either to expand or to contract. When the soil is induced to expand due to sound waves, it can contract naturally and return to the condition it was in before the influence of the sound waves. On the contrary, when the soil is induced to contract, it is unable to return to its initial condition. Due to the results discussed above, it is suggested that sound waves causing soil to expand have a temporary impact while those causing soil to contract have a permanent impact. In addition, our experimental results show how sound waves affect the water retention curve at different depths. The degree of soil expansion and contraction caused by the sound waves will differ at various soil depths. Nevertheless, the expanding or contracting of soil is only subject to the

Triticonazole enantiomers: Separation by supercritical fluid chromatography and the effect of the chromatographic conditions.

PubMed

He, Jianfeng; Fan, Jun; Yan, Yilun; Chen, Xiaodong; Wang, Tai; Zhang, Yaomou; Zhang, Weiguang

2016-11-01

Enantiomeric pairs of triticonazole have been successfully separated by supercritical fluid chromatography coupled with a tris(3,5-dimethylphenylcarbamoyl) cellulose-coated chiral stationary phase in this work. The effects of co-solvent, dissolution solvent, flow rate, backpressure, and column temperature have been studied in detail with respect to retention, selectivity, and resolution of triticonazole. As indicated, the co-solvents mostly affected the retention factors and resolution, due to the different molecular structure and polarity. In addition, the dissolution solvents, namely, chloromethanes and alcohols, have been also important for enantioseparation because of the different interaction with stationary phase. Higher flow rate and backpressure led to faster elution of the triticonazole molecules, and the change of column temperature showed slight effect on the resolution of triticonazole racemate. Moreover, a comparative separation experiment between supercritical fluid chromatography and high performance liquid chromatography revealed that chiral supercritical fluid chromatography gave the 3.5 times value of R s /t R2 than high performance liquid chromatography, which demonstrated that supercritical fluid chromatography had much higher separation efficiency. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Theory for nanoparticle retention time in the helical channel of quadrupole magnetic field-flow fractionation

NASA Astrophysics Data System (ADS)

Williams, P. Stephen; Carpino, Francesca; Zborowski, Maciej

2009-05-01

Quadrupole magnetic field-flow fractionation (QMgFFF) is a separation and characterization technique for magnetic nanoparticles such as those used for cell labeling and for targeted drug therapy. A helical separation channel is used to efficiently exploit the quadrupole magnetic field. The fluid and sample components therefore have angular and longitudinal components to their motion in the thin annular space occupied by the helical channel. The retention ratio is defined as the ratio of the times for non-retained and a retained material to pass through the channel. Equations are derived for the respective angular and longitudinal components to retention ratio.

Retention of minority participants in clinical research studies.

PubMed

Keller, Colleen S; Gonzales, Adelita; Fleuriet, K Jill

2005-04-01

Recruitment of minority participants for clinical research studies has been the topic of several analytical works. Yet retention of participants, most notably minority and underserved populations, is less reported and understood, even though these populations have elevated health risks. This article describes two related, intervention-based formative research projects in which researchers used treatment theory to address issues of recruitment and retention of minority women participants in an exercise program to reduce obesity. Treatment theory incorporates a model of health promotion that allows investigators to identify and control sources of extraneous variables. The authors' research demonstrates that treatment theory can improve retention of minority women participants by considering critical inputs, mediating processes, and substantive participant characteristics in intervention design.

Retention of Pictorial and Verbal Content of A Text with Illustrations

ERIC Educational Resources Information Center

Peeck, J.

1974-01-01

Questioning why illustrated text is commonly used for children in the absence of significant proof of its usefulness, the present author undertook a study to measure fourth graders' retention of three variations of a story book text. Results indicate illustrations have several effects on retention. (BJG)

[Fluid therapy in acute pancreatitis].

PubMed

de-Madaria, Enrique

2013-12-01

Severe acute pancreatitis (AP) is associated with an increased need for fluids due to fluid sequestration and, in the most severe cases, with decreased peripheral vascular tone. For several decades, clinical practice guidelines have recommended aggressive fluid therapy to improve the prognosis of AP. This recommendation is based on theoretical models, animal studies, and retrospective studies in humans. Recent studies suggest that aggressive fluid administration in all patients with AP could have a neutral or harmful effect. Fluid therapy based on Ringer's lactate could improve the course of the disease, although further studies are needed to confirm this possibility. Most patients with AP do not require invasive monitoring of hemodynamic parameters to guide fluid therapy administration. Moreover, the ability of these parameters to improve prognosis has not been demonstrated. Copyright © 2013 Elsevier España, S.L. and AEEH y AEG. All rights reserved.

What predicts retention on an in-prison drug treatment program?

PubMed

Casares-López, María José; González-Menéndez, Ana; Fernández, Paula; Secades-Villa, Roberto; Fernández-Hermida, José Ramón

2012-11-01

The effectiveness of treatments for substance use disorders is strongly related to retention, since early dropout from treatment is associated with greater likelihood of relapse. The purpose of this prospective, ex post facto study is to analyze the effect of individual variables on retention in a treatment program carried out in a prison drug-free unit. The Addiction Severity Index, motivation and personality profile of fifty inmates were assessed on entry to the prison. Inmates were monitored for a year to identify length of stay. Motivation variables at intake play a vital role in the prediction of retention in a prison drug-free unit; scores on the Aggressive-Sadistic and Narcissistic scales are also strong predictors of treatment retention.

Measuring SeHCAT retention: a technical note.

PubMed

Notghi, Alp; O'Brien, Joseph; Low, Chen Sheng; Thomson, William

2011-10-01

TauroH-23-((75)Se)selena-25-homocholic acid (SeHCAT) retention has been used for the diagnosis of bile acid malabsorption since the early 1980s. Bile acid malabsorption has been increasingly recognized as an important cause of severe chronic diarroea with subsequent increase in the number of referrals for the SeHCAT test. In this study, we review and discuss the standard techniques for the measurement of SeHCAT retention and describe a simple and modified technique using a noncollimated whole-body scanner, suitable for most modern dual-headed cameras.

Fluid balance, glomerular filtration rate, and urine output in dogs anesthetized for an orthopedic surgical procedure.

PubMed

Boscan, Pedro; Pypendop, Bruno H; Siao, Kristine T; Francey, Thierry; Dowers, Kristy; Cowgill, Larry; Ilkiw, Jan E

2010-05-01

To determine fluid retention, glomerular filtration rate, and urine output in dogs anesthetized for a surgical orthopedic procedure. 23 dogs treated with a tibial plateau leveling osteotomy. 12 dogs were used as a control group. Cardiac output was measured in 5 dogs, and 6 dogs received carprofen for at least 14 days. Dogs received oxymorphone, atropine, propofol, and isoflurane for anesthesia (duration, 4 hours). Urine and blood samples were obtained for analysis every 30 minutes. Lactated Ringer's solution was administered at 10 mL/kg/h. Urine output was measured and glomerular filtration rate was estimated. Fluid retention was measured by use of body weight, fluid balance, and bioimpedance spectroscopy. No difference was found among control, cardiac output, or carprofen groups, so data were combined. Median urine output and glomerular filtration rate were 0.46 mL/kg/h and 1.84 mL/kg/min. Dogs retained a large amount of fluids during anesthesia, as indicated by increased body weight, positive fluid balance, increased total body water volume, and increased extracellular fluid volume. The PCV, total protein concentration, and esophageal temperature decreased in a linear manner. Dogs anesthetized for a tibial plateau leveling osteotomy retained a large amount of fluids, had low urinary output, and had decreased PCV, total protein concentration, and esophageal temperature. Evaluation of urine output alone in anesthetized dogs may not be an adequate indicator of fluid balance.

[Academic stress, desertion, and retention strategies for students in higher education].

PubMed

Suárez-Montes, Nancy; Díaz-Subieta, Luz B

2015-04-01

A systematic review was performed to specify the characteristics of academic stress that affect the mental health of the university population. To do this, recent publications regarding academic stress, student desertion, and retention strategies were examined. Throughout this text, we present the results of the review in terms of the definitions of academic stress, student desertion, and retention strategies. In the same way, we examine the interpretative models with regard to student desertion and approach retention strategies in higher education. We also review retention experiences of several other countries. In terms of Colombia, we present aspects related to student desertion and retention programs from the point of view of the National Ministry of Education and from the experience of some universities with consolidated programs.

Nuclear reactor melt-retention structure to mitigate direct containment heating

DOEpatents

Tutu, Narinder K.; Ginsberg, Theodore; Klages, John R.

1991-01-01

A light water nuclear reactor melt-retention structure to mitigate the extent of direct containment heating of the reactor containment building. The structure includes a retention chamber for retaining molten core material away from the upper regions of the reactor containment building when a severe accident causes the bottom of the pressure vessel of the reactor to fail and discharge such molten material under high pressure through the reactor cavity into the retention chamber. In combination with the melt-retention chamber there is provided a passageway that includes molten core droplet deflector vanes and has gas vent means in its upper surface, which means are operable to deflect molten core droplets into the retention chamber while allowing high pressure steam and gases to be vented into the upper regions of the containment building. A plurality of platforms are mounted within the passageway and the melt-retention structure to direct the flow of molten core material and help retain it within the melt-retention chamber. In addition, ribs are mounted at spaced positions on the floor of the melt-retention chamber, and grid means are positioned at the entrance side of the retention chamber. The grid means develop gas back pressure that helps separate the molten core droplets from discharged high pressure steam and gases, thereby forcing the steam and gases to vent into the upper regions of the reactor containment building.

Contribution of pitcher fragrance and fluid viscosity to high prey diversity in a Nepenthes carnivorous plant from Borneo.

PubMed

Giusto, Bruno Di; Grosbois, Vladimir; Fargeas, Elodie; Marshall, David J; Gaume, Laurence

2008-03-01

Mechanisms that improve prey richness in carnivorous plants may involve three crucial phases of trapping:attraction, capture and retention. Nepenthes rafflesiana var. typica is an insectivorous pitcher plant that is widespread in northern Borneo. It exhibits ontogenetic pitcher dimorphism with the upper pitchers trapping more flying prey than the lower pitchers. While this difference in prey composition has been ascribed to differences in attraction,the contribution of capture and retention has been overlooked. This study focused on distinguishing between the prey trapping mechanisms, and assessing their relative contribution to prey diversity. Arthropod richness and diversity of both visitors and prey in the two types of pitchers were analysed to quantify the relative contribution of attraction to prey trapping. Rate of insect visits to the different pitcher parts and the presence or absence of a sweet fragrance was recorded to clarify the origin and mechanism of attraction. The mechanism of retention was studied by insect bioassays and measurements of fluid viscosity. Nepenthes rafflesiana was found to trap a broader prey spectrum than that previously described for any Nepenthes species,with the upper pitchers attracting and trapping a greater quantity and diversity of prey items than the lower pitchers. Capture efficiency was low compared with attraction or retention efficiency. Fragrance of the peristome,or nectar rim,accounted mainly for the observed non-specific, better prey attraction by the upper pitchers, while the retentive properties of the viscous fluid in these upper pitchers arguably explains the species richness of their flying prey. The pitchers of N. rafflesiana are therefore more than simple pitfall traps and the digestive fluid plays an important yet unsuspected role in the ecological success of the species.

Tritium retention in reduced-activation ferritic/martensitic steels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hatano, Y.; Abe, S.; Matsuyama, M.

Reduced-activation ferritic/martensitic (RAFM) steels are structural material candidates for breeding blankets of future fusion reactors. Therefore, tritium (T) retention in RAFM steels is an important problem in assessing the T inventory of blankets. In this study, specimens of RAFM steels were subjected to irradiation of 20 MeV W ions to 0.54 displacements per atom (dpa), exposure to high flux D plasmas at 400 and 600 K and that to pulsed heat loads. The specimens thus prepared were exposed to DT gas at 473 K. Despite severe modification in the surface morphology, heat loads had negligible effects on T retention. Significantmore » increase in T retention at the surface and/or subsurface was observed after D plasma exposure. However, T trapped at the surface/subsurface layer was easily removed by maintaining the specimens in the air at about 300 K. Displacement damage led to increase in T retention in the bulk due to the trapping effects of defects, and T trapped was stable at 300 K. It was therefore concluded that displacement damages had the largest influence on T retention under the present conditions.« less

The reliability of the physical examination to guide fluid therapy in adults with severe falciparum malaria: an observational study

PubMed Central

2013-01-01

Background Adults with severe malaria frequently require intravenous fluid therapy to restore their circulating volume. However, fluid must be delivered judiciously as both under- and over-hydration increase the risk of complications and, potentially, death. As most patients will be cared for in a resource-poor setting, management guidelines necessarily recommend that physical examination should guide fluid resuscitation. However, the reliability of this strategy is uncertain. Methods To determine the ability of physical examination to identify hypovolaemia, volume responsiveness, and pulmonary oedema, clinical signs and invasive measures of volume status were collected independently during an observational study of 28 adults with severe malaria. Results The physical examination defined volume status poorly. Jugular venous pressure (JVP) did not correlate with intravascular volume as determined by global end diastolic volume index (GEDVI; rs = 0.07, p = 0.19), neither did dry mucous membranes (p = 0.85), or dry axillae (p = 0.09). GEDVI was actually higher in patients with decreased tissue turgor (p < 0.001). Poor capillary return correlated with GEDVI, but was present infrequently (7% of observations) and, therefore, insensitive. Mean arterial pressure (MAP) correlated with GEDVI (rs = 0.16, p = 0.002), but even before resuscitation patients with a low GEDVI had a preserved MAP. Anuria on admission was unrelated to GEDVI and although liberal fluid resuscitation led to a median hourly urine output of 100 ml in 19 patients who were not anuric on admission, four (21%) developed clinical pulmonary oedema subsequently. MAP was unrelated to volume responsiveness (p = 0.71), while a low JVP, dry mucous membranes, dry axillae, increased tissue turgor, prolonged capillary refill, and tachycardia all had a positive predictive value for volume responsiveness of ≤50%. Extravascular lung water ≥11 ml/kg indicating pulmonary oedema was

Hematuria and clot retention after transvaginal oocyte aspiration: a case report.

PubMed

Modder, Joshua; Kettel, L Michael; Sakamoto, Kyoko

2006-09-01

To report a case of bladder injury with hematuria and urinary retention after transvaginal oocyte aspiration. Case report. Emergency room in a university medical center. A 28-year-old woman presented with urinary retention and suprapubic pain 8 hours after oocyte aspiration. Foley catheter, intravenous fluid bolus, bladder irrigation, and computed tomography with postvoid films that showed a blood clot in the bladder. Patient was discharged home with antibiotics and catheter in place. Clinical follow-up. Patient passed voiding trial 4 days later and was artificially inseminated. No further hematuria or voiding problems were reported, and she had a successful pregnancy. Patients who elect to undergo oocyte aspiration should be warned about the possibility of bladder injury because of the close proximity of the ovaries to the bladder, and physicians should have an appropriate treatment plan.

Influence of the operational parameters on bioelectricity generation in continuous microbial fuel cell, experimental and computational fluid dynamics modelling

NASA Astrophysics Data System (ADS)

Sobieszuk, Paweł; Zamojska-Jaroszewicz, Anna; Makowski, Łukasz

2017-12-01

The influence of the organic loading rate (also known as active anodic chamber volume) on bioelectricity generation in a continuous, two-chamber microbial fuel cell for the treatment of synthetic wastewater, with glucose as the only carbon source, was examined. Ten sets of experiments with different combinations of hydraulic retention times (0.24-1.14 d) and influent chemical oxygen demand concentrations were performed to verify the impact of organic loading rate on the voltage generation capacity of a simple dual-chamber microbial fuel cell working in continuous mode. We found that there is an optimal hydraulic retention time value at which the maximum voltage is generated: 0.41 d. However, there were no similar effects, in terms of voltage generation, when a constant hydraulic retention time with different influent chemical oxygen demand of wastewater was used. The obtained maximal voltage value (600 mV) has also been compared to literature data. Computational fluid dynamics (CFD) was used to calculate the fluid flow and the exit age distribution of fluid elements in the reactor to explain the obtained experimental results and identify the crucial parameters for the design of bioreactors on an industrial scale.

A theoretical model of job retention for home health care nurses.

PubMed

Ellenbecker, Carol Hall

2004-08-01

Predicted severe nursing shortages and an increasing demand for home health care services have made the retention of experienced, qualified nursing staff a priority for health care organizations. The purpose of this paper is to describe a theoretical model of job retention for home health care nurses. The theoretical model is an integration of the findings of empirical research related to intent to stay and retention, components of Neal's theory of home health care nursing practice and findings from earlier work to develop an instrument to measure home health care nurses' job satisfaction. The theoretical model identifies antecedents to job satisfaction of home health care nurses. The antecedents are intrinsic and extrinsic job characteristics. The model also proposes that job satisfaction is directly related to retention and indirectly related to retention though intent to stay. Individual nurse characteristics are indirectly related to retention through intent to stay. The individual characteristic of tenure is indirectly related to retention through autonomy, as an intrinsic characteristic of job satisfaction, and intent to stay. The proposed model can be used to guide research that explores gaps in knowledge about intent to stay and retention among home health care nurses.

Combination of partial least squares regression and design of experiments to model the retention of pharmaceutical compounds in supercritical fluid chromatography.

PubMed

Andri, Bertyl; Dispas, Amandine; Marini, Roland Djang'Eing'a; Hubert, Philippe; Sassiat, Patrick; Al Bakain, Ramia; Thiébaut, Didier; Vial, Jérôme

2017-03-31

This work presents a first attempt to establish a model of the retention behaviour for pharmaceutical compounds in gradient mode SFC. For this purpose, multivariate statistics were applied on the basis of data gathered with the Design of Experiment (DoE) methodology. It permitted to build optimally the experiments needed, and served as a basis for providing relevant physicochemical interpretation of the effects observed. Data gathered over a broad experimental domain enabled the establishment of well-fit linear models of the retention of the individual compounds in presence of methanol as co-solvent. These models also allowed the appreciation of the impact of each experimental parameter and their factorial combinations. This approach was carried out with two organic modifiers (i.e. methanol and ethanol) and provided comparable results. Therefore, it demonstrates the feasibility to model retention in gradient mode SFC for individual compounds as a function of the experimental conditions. This approach also permitted to highlight the predominant effect of some parameters (e.g. gradient slope and pressure) on the retention of compounds. Because building of individual models of retention was possible, the next step considered the establishment of a global model of the retention to predict the behaviour of given compounds on the basis of, on the one side, the physicochemical descriptors of the compounds (e.g. Linear Solvation Energy Relationship (LSER) descriptors) and, on the other side, of the experimental conditions. This global model was established by means of partial least squares regression for the selected compounds, in an experimental domain defined by the Design of Experiment (DoE) methodology. Assessment of the model's predictive capabilities revealed satisfactory agreement between predicted and actual retention (i.e. R 2 =0.942, slope=1.004) of the assessed compounds, which is unprecedented in the field. Copyright © 2017 Elsevier B.V. All rights reserved.

Decreased synovial fluid ghrelin levels are linked with disease severity in primary knee osteoarthritis patients and are increased following laser therapy.

PubMed

Zou, Yu-Cong; Deng, Hong-Yu; Mao, Zheng; Zhao, Chang; Huang, Ju; Liu, Gang

2017-07-01

Ghrelin has been proved to inhibit inflammation and promote cartilage growth. So far, its role in patients with primary knee osteoarthritis has not been investigated. The current study was performed to explore the serum and synovial ghrelin levels as well as the relationship between ghrelin levels and disease severity in primary knee OA patients. 52 primary knee OA patients were recruited in the study. 52 sex and age-matched patients visiting our hospital for regular body check were selected as controls. The serum and synovial fluid ghrelin levels were examined by enzyme linked immunosorbent assay (ELISA) before treatment, one week and four weeks after laser therapy, respectively. The inflammation markers IL-6 and TNF-α were also investigated. The radiographic progression was assessed by Kellgren-Lawrence (K-L) grade scale and the symptomatic severity was evaluated by visual analog scale (VAS), Lequesne index and Lysholm scores. The Receiver Operating Characteristic (ROC) analysis curve was conducted to test the diagnostic value of ghrelin, IL-6 and TNF-α for radiographic progression. No significant difference of serum ghrelin levels was found between knee OA patients and healthy controls. Synovial fluid ghrelin concentrations were significantly negatively correlated with K-L grading (r=-0.591, P<0.001).Attenuated synovial fluid ghrelin levels were also related to clinical severity determined by Lequesne index (r=-0.308, P=0.025),VAS scores (r=-0.591, P<0.001) and Lysholm scores (r=0.381, P=0.005).In addition, ghrelin levels were also negatively associated with TNF-α (r=-0.424, P=0.002) and IL-6 concentrations (r=-0.428, P=0.002). ROC curve analysis demonstrated that ghrelin exhibited more diagnostic value than IL-6 and TNF-α for assessing radiographic progression in medium-late stage. Decreased synovial fluid ghrelin levels are related to disease severity in patients with primary osteoarthritis and are increased following laser therapy. Local application of

The reliability and predictive value of an amniotic fluid scoring system in severe second-trimester oligohydramnios.

PubMed

Moore, T R; Longo, J; Leopold, G R; Casola, G; Gosink, B B

1989-05-01

Sixty-two cases of oligohydramnios diagnosed by ultrasound between 13-28 weeks' gestation were reviewed. Three experienced ultrasonographers used a subjective scale to rate the oligohydramnios as mild, moderate, severe, or anhydramniotic. Interobserver reliability was excellent (intraclass correlation coefficient 0.81). The overall perinatal mortality rate was 43%, and the incidence of pulmonary hypoplasia was 33%. One-third had lethal congenital anomalies. The frequency of adverse outcome correlated strongly with the most severe degrees of oligohydramnios; 88% of the fetuses with severe oligohydramnios or anhydramnios had lethal outcomes, compared with 11% in the mild/moderate group. The presence of an anuric urinary tract anomaly was associated with the most severe grades of oligohydramnios and was uniformly fatal. Pulmonary hypoplasia was diagnosed in 60% of the severe group versus 6% in the moderate group. We conclude that subjective grading of oligohydramnios by experienced observers is both reliable and predictive of outcome. The finding of severe oligohydramnios in the second trimester is highly predictive of poor fetal outcome and should stimulate a thorough search for etiology and consideration of intervention. Moderate grades of reduced amniotic fluid may be managed with relative optimism.

The (pro)renin receptor and body fluid homeostasis

PubMed Central

Cao, Theresa

2013-01-01

The renin-angiotensin system (RAS) has long been established as one of the major mechanisms of hypertension through the increased levels of angiotensin (ANG) II and its resulting effect on the sympathetic nerve activity, arterial vasoconstriction, water reabsorption, and retention, etc. In the central nervous system, RAS activation affects body fluid homeostasis through increases in sympathetic nerve activity, water intake, food intake, and arginine vasopressin secretion. Previous studies, however, have shown that ANG II can be made in the brain, and it could possibly be through a new component called the (pro)renin receptor. This review intends to summarize the central and peripheral effects of the PRR on body fluid homeostasis. PMID:23678024

Undergraduate STEM Achievement and Retention: Cognitive, Motivational, and Institutional Factors and Solutions

ERIC Educational Resources Information Center

Cromley, Jennifer G.; Perez, Tony; Kaplan, Avi

2016-01-01

Student cognition and motivation, as well as institutional policies, determine student course grades and retention in science, technology, engineering, and mathematics (STEM) majors. Regarding cognition, study skills relate to course grades, and grades relate to retention in STEM. Several aspects of motivation are related to both grades and…

Pericardial fluid level of heart-type cytoplasmic fatty acid-binding protein (H-FABP) is an indicator of severe myocardial ischemia.

PubMed

Tambara, Keiichi; Fujita, Masatoshi; Miyamoto, Shoichi; Doi, Kazuhiko; Nishimura, Kazunobu; Komeda, Masashi

2004-02-01

Heart-type cytoplasmic fatty acid-binding protein (H-FABP) has been reported as a sensitive and specific marker for the early diagnosis of acute myocardial infarction. Our hypothesis was that serum or pericardial fluid levels of H-FABP can reflect not only myocardial infarction but also myocardial ischemia. A total of 34 patients with unstable angina, who had anginal symptoms and/or ST-changes in ECG monitoring within 24 h before operation, were classified into group A (n=17), and those without these symptoms and changes into group B (n=17). Blood and pericardial fluid samples were obtained immediately after median sternotomy, and serum and pericardial fluid levels of creatine kinase-MB, cardiac troponin-T, and H-FABP were measured. Serum H-FABP levels were slightly elevated compared with their normal values in both groups. While they showed no difference between groups A and B (group A vs. B: 8.5+/-1.0 vs. 7.1+/-0.7 ng/ml, P=0.25), pericardial fluid levels of H-FABP were significantly higher in group A than in group B (16.3+/-2.0 vs. 9.6+/-1.0 ng/ml, P=0.0046). H-FABP showed a weak correlation between its serum levels and pericardial fluid levels (r=0.40). Pericardial fluid levels of H-FABP reflect myocardial ischemia occurring within 24 h of their measurements. H-FABP may be secreted into the interstitial space by increased permeability of the myocardial cell membrane associated with severe myocardial ischemia. Thus, pericardial fluid reflects pathophysiological conditions of cardiomyocytes more sensitively than circulating blood.

Fuel nozzle tube retention

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cihlar, David William; Melton, Patrick Benedict

A system for retaining a fuel nozzle premix tube includes a retention plate and a premix tube which extends downstream from an outlet of a premix passage defined along an aft side of a fuel plenum body. The premix tube includes an inlet end and a spring support feature which is disposed proximate to the inlet end. The premix tube extends through the retention plate. The spring retention feature is disposed between an aft side of the fuel plenum and the retention plate. The system further includes a spring which extends between the spring retention feature and the retention plate.

Elastic properties of a magnetic fluid with an air cavity retained by levitation forces

NASA Astrophysics Data System (ADS)

Polunin, V. M.; Boev, M. L.; Tan, Myo Min; Karpova, G. V.; Roslyakova, L. I.

2013-01-01

The paper describes the process of an air cavity rising in a magnetic fluid filling a tube with a bottom, transport, and retention of the cavity by magnetic levitation forces. The elastic and dissipative properties of a vibratory system with an inertial element that is a column of a magnetic fluid over an air cavity are considered. The possibility of using a transported air cavity as a movable reflector for a sound wave is evaluated.

Maternal Serum and Amniotic Fluid Inhibin A Levels in Women who Subsequently Develop Severe Preeclampsia

PubMed Central

Kim, Shin-Young; Yang, Jae-Hyug; Kim, Moon-Young; Ahn, Hyun-Kyong; Shin, Joong-Sik; Choi, Jun-Seek; Park, So-Yeon; Kim, Jin-Mi; Lee, Bom-Yi; Kim, Do-Jin

2006-01-01

The purpose of this study was to evaluate whether maternal serum (MS) and amniotic fluid (AF) inhibin A levels are elevated in patients who subsequently develop severe preecalmpsia, and to investigate the correlation between MS and AF inhibin A levels in the second trimester. The study included 40 patients who subsequently developed severe preecalmpsia and 80 normal pregnant women. Inhibin A levels in MS and AF were measured with enzyme-linked immunosorbent assay (ELISA). The MS and AF inhibin A levels in patients who developed severe preeclampsia were significantly higher than those in the control group (both for p<0.001). There was a positive correlation between MS and AF inhibin A levels in patients who developed severe preeclampsia (r=0.397, p=0.011), but not in the control group (r=0.185, p=0.126). The best cutoff values of MS and AF inhibin A levels for the prediction of severe preeclampsia were 427 pg/mL and 599 pg/mL, respectively; the estimated ORs that were associated with these cut-off values were 9.95 (95% CI 3.8-25.9, p<0.001) and 6.0 (95% CI 2.3-15.8, p<0.001). An elevated level of inhibin A in MS and AF at the time of second trimester amniocentesis may be a risk factor for the subsequent development of severe preeclampsia. PMID:16778388

A unified classification of stationary phases for packed column supercritical fluid chromatography.

PubMed

West, C; Lesellier, E

2008-05-16

The use of supercritical fluids as chromatographic mobile phases allows to obtain rapid separations with high efficiency on packed columns, which could favour the replacement of numerous HPLC methods by supercritical fluid chromatography (SFC) ones. Moreover, despite some unexpected chromatographic behaviours, general retention rules are now well understood, and mainly depend on the nature of the stationary phase. The use of polar stationary phases improves the retention of polar compounds, when C18-bonded silica favours the retention of hydrocarbonaceous compounds. In this sense, reversed-phase and normal-phase chromatography can be achieved in SFC, as in HPLC. However, these two domains are clearly separated in HPLC due to the opposite polarity of the mobile phases used for each method. In SFC, the same mobile phase can be used with both polar and non-polar stationary phases. Consequently, the need for a novel classification of stationary phases in SFC appears, allowing a unification of the classical reversed- and normal-phase domains. In this objective, the paper presents the development of a five-dimensional classification based on retention data for 94-111 solutes, using 28 commercially available columns representative of three major types of stationary phases. This classification diagram is based on a linear solvation energy relationship, on the use of solvation vectors and the calculation of similarity factors between the different chromatographic systems. This classification will be of great help in the choice of the well-suited stationary phase, either in regards of a particular separation or to improve the coupling of columns with complementary properties.

Ecosystem Nitrogen Retention Following Severe Bark Beetle and Salvage Logging Disturbance in Lodgepole Pine Forests: a 15N Enrichment Study

NASA Astrophysics Data System (ADS)

Avera, B.; Rhoades, C.; Paul, E. A.; Cotrufo, M. F.

2017-12-01

In recent decades, bark beetle outbreaks have caused high levels of tree mortality in lodgepole pine (Pinus contorta) dominated forests across western North America. Previous work has found increased soil mineral nitrogen (N) with tree mortality in beetle infested stands, but surprisingly little change in stream N export. These findings suggest an important role of residual live vegetation and altered soil microbial response for retaining surplus N and mitigating N losses from disturbed lodgepole forests. Post outbreak salvage of merchantable timber reduces fuel levels and promotes tree regeneration; however, the implications of the combined bark beetle and harvesting disturbances on ecosystem N retention and productivity are uncertain. To advance understanding of post-disturbance N retention we compare unlogged beetle-infested forests and salvage logged stands with post-harvest woody residue retention or removal. We applied 15N-labeled (2 atom%) and natural abundance ammonium sulfate to eight year old lodgepole pine seedlings in three replicate plots of the three forest management treatments. This approach allows us to quantify the relative contributions of N retention in soil, microbial biomass, and plant tissue. Our study targets gaps in understanding of the processes that regulate N utilization and transfer between soil and vegetation that result in effective N retention in lodgepole pine ecosystems. These findings will also help guide forest harvest and woody residue management practices in order to maintain soil productivity.

Fluid resuscitation in acute pancreatitis

PubMed Central

Aggarwal, Aakash; Manrai, Manish; Kochhar, Rakesh

2014-01-01

Acute pancreatitis remains a clinical challenge, despite an exponential increase in our knowledge of its complex pathophysiological changes. Early fluid therapy is the cornerstone of treatment and is universally recommended; however, there is a lack of consensus regarding the type, rate, amount and end points of fluid replacement. Further confusion is added with the newer studies reporting better results with controlled fluid therapy. This review focuses on the pathophysiology of fluid depletion in acute pancreatitis, as well as the rationale for fluid replacement, the type, optimal amount, rate of infusion and monitoring of such patients. The basic goal of fluid epletion should be to prevent or minimize the systemic response to inflammatory markers. For this review, various studies and reviews were critically evaluated, along with authors’ recommendations, for predicted severe or severe pancreatitis based on the available evidence. PMID:25561779

The contributions of encoding, retention, and recall to the Hebb effect.

PubMed

Oberauer, Klaus; Meyer, Nadine

2009-10-01

The article reports an experiment testing whether the Hebb repetition effect-the gradual improvement of immediate serial recall when the same list is repeated several times-depends on overt recall of the repeated lists. Previous reports which suggest that recall is critical confound the recall manipulation with retention interval. The present experiment orthogonally varies retention interval (0 or 9 s) and whether the list is to be recalled after the retention interval. Hebb repetition learning is assessed in a final test phase. A repetition effect was obtained in all four experimental conditions; it was larger for recalled than non-recalled lists, whereas retention interval had no effect. The results show that encoding is sufficient to generate cumulative long-term learning, which is strengthened by recall. Rehearsal, if it takes place in the retention interval at all, does not have the same effect on long-term learning as overt recall.

Coupled fluid and solid mechanics study for improved permeability estimation of fines' invaded porous materials

NASA Astrophysics Data System (ADS)

Mirabolghasemi, M.; Prodanovic, M.

2012-12-01

The problem of fine particle infiltration is seen in fields from subsurface transport, to drug delivery to industrial slurry flows. Sediment filtration and pathogen retention are well-known subsurface engineering problems that have been extensively studied through different macroscopic, microscopic and experimental modeling techniques Due to heterogeneity, standard constitutive relationships and models yield poor predictions for flow (e.g. permeability) and rock properties (e.g. elastic moduli) of the invaded (damaged) porous media. This severely reduces our ability to, for instance, predict retention, pressure build-up, newly formed flow pathways or porous medium mechanical behavior. We chose a coupled computational fluid dynamics (CFD) - discrete element modeling (DEM) approach to simulate the particulate flow through porous media represented by sphere packings. In order to minimize the uncertainty involved in estimating the flow properties of porous media on Darcy scale and address the dynamic nature of filtration process, this microscopic approach is adapted as a robust method that can incorporate particle interaction physics as well as the heterogeneity of the porous medium.. The coupled simulation was done in open-source packages which has both CFD (openFOAM) and DEM components (LIGGGHTS). We ran several sensitivity analyses over different parameters such as particle/grain size ratio, fluid viscosity, flow rate and sphere packing porosity in order to investigate their effects on the depth of invasion and damaged porous medium permeability. The response of the system to the variation of different parameters is reflected through different clogging mechanism; for instance, bridging is the dominant mechanism of pore-throat clogging when larger particles penetrate into the packing, whereas, in case of fine particles which are much smaller than porous medium grains (1/20 in diameter), this mechanism is not very effective due to the frequent formation and

Retention of ingested porcine reproductive and respiratory syndrome virus in houseflies.

PubMed

Schurrer, Jennifer A; Dee, Scott A; Moon, Roger D; Murtaugh, Michael P; Finnegan, Colleen P; Deen, John; Kleiboeker, Steven B; Pijoan, Carlos B J

2005-09-01

To evaluate retention of porcine reproductive and respiratory syndrome virus (PRRSV) in houseflies for various time frames and temperatures. Fifteen 2-week-old pigs, two 10-week-old pigs, and laboratory-cultivated houseflies. In an initial experiment, houseflies were exposed to PRRSV; housed at 15 degrees, 20 degrees, 25 degrees, and 30 degrees C; and tested at various time points. In a second experiment to determine dynamics of virus retention, houseflies were exposed to PRRSV and housed under controlled field conditions for 48 hours. Changes in the percentage of PRRSV-positive flies and virus load per fly were assessed over time, and detection of infective virus at 48 hours after exposure was measured. Finally, in a third experiment, virus loads were measured in houseflies allowed to feed on blood, oropharyngeal washings, and nasal washings obtained from experimentally infected pigs. In experiment 1, PRRSV retention in houseflies was proportional to temperature. In the second experiment, the percentage of PRRSV-positive houseflies and virus load per fly decreased over time; however, infective PRRSV was found in houseflies 48 hours after exposure. In experiment 3, PRRSV was detected in houseflies allowed to feed on all 3 porcine body fluids. For the conditions of this study, houseflies did not support PRRSV replication. Therefore, retention of PRRSV in houseflies appears to be a function of initial virus load after ingestion and environmental temperature. These factors may impact the risk of insect-borne spread of PRRSV among farms.

Compression in Working Memory and Its Relationship With Fluid Intelligence.

PubMed

Chekaf, Mustapha; Gauvrit, Nicolas; Guida, Alessandro; Mathy, Fabien

2018-06-01

Working memory has been shown to be strongly related to fluid intelligence; however, our goal is to shed further light on the process of information compression in working memory as a determining factor of fluid intelligence. Our main hypothesis was that compression in working memory is an excellent indicator for studying the relationship between working-memory capacity and fluid intelligence because both depend on the optimization of storage capacity. Compressibility of memoranda was estimated using an algorithmic complexity metric. The results showed that compressibility can be used to predict working-memory performance and that fluid intelligence is well predicted by the ability to compress information. We conclude that the ability to compress information in working memory is the reason why both manipulation and retention of information are linked to intelligence. This result offers a new concept of intelligence based on the idea that compression and intelligence are equivalent problems. Copyright © 2018 Cognitive Science Society, Inc.

Assessing the potential contributions of additional retention processes to PFAS retardation in the subsurface.

PubMed

Brusseau, Mark L

2018-02-01

A comprehensive understanding of the transport and fate of per- and poly-fluoroalkyl substances (PFAS) in the subsurface is critical for accurate risk assessments and design of effective remedial actions. A multi-process retention model is proposed to account for potential additional sources of retardation for PFAS transport in source zones. These include partitioning to the soil atmosphere, adsorption at air-water interfaces, partitioning to trapped organic liquids (NAPL), and adsorption at NAPL-water interfaces. An initial assessment of the relative magnitudes and significance of these retention processes was conducted for two PFAS of primary concern, perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), and an example precursor (fluorotelomer alcohol, FTOH). The illustrative evaluation was conducted using measured porous-medium properties representative of a sandy vadose-zone soil. Data collected from the literature were used to determine measured or estimated values for the relevant distribution coefficients, which were in turn used to calculate retardation factors for the model system. The results showed that adsorption at the air-water interface was a primary source of retention for both PFOA and PFOS, contributing approximately 50% of total retention for the conditions employed. Adsorption to NAPL-water interfaces and partitioning to bulk NAPL were also shown to be significant sources of retention. NAPL partitioning was the predominant source of retention for FTOH, contributing ~98% of total retention. These results indicate that these additional processes may be, in some cases, significant sources of retention for subsurface transport of PFAS. The specific magnitudes and significance of the individual retention processes will depend upon the properties and conditions of the specific system of interest (e.g., PFAS constituent and concentration, porous medium, aqueous chemistry, fluid saturations, co-contaminants). In cases wherein these

Retention interval affects visual short-term memory encoding.

PubMed

Bankó, Eva M; Vidnyánszky, Zoltán

2010-03-01

Humans can efficiently store fine-detailed facial emotional information in visual short-term memory for several seconds. However, an unresolved question is whether the same neural mechanisms underlie high-fidelity short-term memory for emotional expressions at different retention intervals. Here we show that retention interval affects the neural processes of short-term memory encoding using a delayed facial emotion discrimination task. The early sensory P100 component of the event-related potentials (ERP) was larger in the 1-s interstimulus interval (ISI) condition than in the 6-s ISI condition, whereas the face-specific N170 component was larger in the longer ISI condition. Furthermore, the memory-related late P3b component of the ERP responses was also modulated by retention interval: it was reduced in the 1-s ISI as compared with the 6-s condition. The present findings cannot be explained based on differences in sensory processing demands or overall task difficulty because there was no difference in the stimulus information and subjects' performance between the two different ISI conditions. These results reveal that encoding processes underlying high-precision short-term memory for facial emotional expressions are modulated depending on whether information has to be stored for one or for several seconds.

Cardiovascular and fluid volume control in humans in space.

PubMed

Norsk, Peter

2005-08-01

The human cardiovascular system and regulation of fluid volume are heavily influenced by gravity. When decreasing the effects of gravity in humans such as by anti-orthostatic posture changes or immersion into water, venous return is increased by some 25%. This leads to central blood volume expansion, which is accompanied by an increase in renal excretion rates of water and sodium. The mechanisms for the changes in renal excretory rates include a complex interaction of cardiovascular reflexes, neuroendocrine variables, and physical factors. Weightlessness is unique to obtain more information on this complex interaction, because it is the only way to completely abolish the effects of gravity over longer periods. Results from space have been unexpected, because astronauts exhibit a fluid and sodium retaining state with activation of the sympathetic nervous system, which subjects during simulations by head-down bed rest do not. Therefore, the concept as to how weightlessness affects the cardiovascular system and modulates regulation of body fluids should be revised and new simulation models developed. Knowledge as to how gravity and weightlessness modulate integrated fluid volume control is of importance for understanding pathophysiology of heart failure, where gravity plays a strong role in fluid and sodium retention.

Comparison of liquid and supercritical fluid chromatography mobile phases for enantioselective separations on polysaccharide stationary phases.

PubMed

Khater, Syame; Lozac'h, Marie-Anne; Adam, Isabelle; Francotte, Eric; West, Caroline

2016-10-07

Analysis and production of enantiomerically pure compounds is a major topic of interest when active pharmaceutical ingredients are concerned. Enantioselective chromatography has become a favourite both at the analytical and preparative scales. High-performance liquid chromatography (HPLC) and supercritical fluid chromatography (SFC) are dominating the scene and are often seen as complementary techniques. Nowadays, for economic and ecologic reasons, SFC may be preferred over normal-phase HPLC (NPLC) as it allows significant reductions in solvent consumption. However, the transfer of NPLC methods to SFC is not always straightforward. In this study, we compare the retention of achiral molecules and separation of enantiomers under supercritical fluid (carbon dioxide with ethanol or isopropanol) and liquid normal-phase (heptane with ethanol or isopropanol) elution modes with polysaccharide stationary phases in order to explore the differences between the retention and enantioseparation properties between the two modes. Chemometric methods (namely quantitative structure-retention relationships and discriminant analysis) are employed to compare the results obtained on a large set of analytes (171 achiral probes and 97 racemates) and gain some understanding on the retention and separation mechanisms. The results indicate that, contrary to popular belief, carbon dioxide - solvent SFC mobile phases are often weaker eluents than liquid mobile phases. It appears that SFC and NPLC elution modes provide different retention mechanisms. While some enantioseparations are unaffected, facilitating the transfer between the two elution modes, other enantioseparations may be drastically different due to different types and strength of interactions contributing to enantioselectivity. Copyright © 2016 Elsevier B.V. All rights reserved.

Factors affecting nurse retention at an academic Magnet® hospital.

PubMed

Buffington, Annsley; Zwink, Jennifer; Fink, Regina; Devine, Deborah; Sanders, Carolyn

2012-05-01

: The aim of this study was to examine the factors affecting the retention of registered nurses (RNs) and validate the revised Casey-Fink Nurse Retention Survey (2009). : Creating an organizational culture of retention may reduce nurse turnover. Focusing on why nurses leave and identifying factors why nurses stay are essential. : A descriptive survey design gathered data from RNs with 1 or more years of experience providing direct patient care and employed in inpatient/ambulatory settings in an acute care, academic, Magnet hospital. : There were no statistically significant relationships between nurse respondents' perceptions of work environment/support/encouragement and age or years of experience. However, there were significant differences between inpatient and ambulatory nurse responses in several key areas including job satisfaction, mentorship, and educational support. Overall, nurses reported feeling a lack of support and recognition from managers. Results provide evidence to support improved strategies to foster nurse retention.

RETENTION OF HALOCARBONS ON A HEXAFLUOROPROPYLENE-EPOXIDE MODIFIED GRAPHITIZED CARBON BLACK, PART 5: HEAVIER ETHANE- AND ETHENE-BASED COMPOUNDS

EPA Science Inventory

The paper gives results of a study of the retention characteristics of 13 heavier ethane-based and 8 ethene-based halocarbon fluids related to alternative refrigerant research as a function of temperature on a stationary phase consisting of a 5% (by mass) coating of a low molecul...

For-Profit versus Nonprofit Colleges: A Predictive Study of Student Retention in Two-Year Community Colleges

ERIC Educational Resources Information Center

Daly, Jon C.

2013-01-01

Student retention has been a significant issue in higher education for several decades. "Two-year colleges" tend to have lower retention rates than four-year colleges (Seidman, 2005, ). Low retention is a problem in both two-year for-profit and nonprofit colleges. The purpose of this study was to ascertain the predictors of retention…

SMN deficiency in severe models of spinal muscular atrophy causes widespread intron retention and DNA damage

PubMed Central

Jangi, Mohini; Fleet, Christina; Cullen, Patrick; Gupta, Shipra V.; Mekhoubad, Shila; Chiao, Eric; Allaire, Norm; Bennett, C. Frank; Rigo, Frank; Krainer, Adrian R.; Hurt, Jessica A.; Carulli, John P.; Staropoli, John F.

2017-01-01

Spinal muscular atrophy (SMA), an autosomal recessive neuromuscular disease, is the leading monogenic cause of infant mortality. Homozygous loss of the gene survival of motor neuron 1 (SMN1) causes the selective degeneration of lower motor neurons and subsequent atrophy of proximal skeletal muscles. The SMN1 protein product, survival of motor neuron (SMN), is ubiquitously expressed and is a key factor in the assembly of the core splicing machinery. The molecular mechanisms by which disruption of the broad functions of SMN leads to neurodegeneration remain unclear. We used an antisense oligonucleotide (ASO)-based inducible mouse model of SMA to investigate the SMN-specific transcriptome changes associated with neurodegeneration. We found evidence of widespread intron retention, particularly of minor U12 introns, in the spinal cord of mice 30 d after SMA induction, which was then rescued by a therapeutic ASO. Intron retention was concomitant with a strong induction of the p53 pathway and DNA damage response, manifesting as γ-H2A.X positivity in neurons of the spinal cord and brain. Widespread intron retention and markers of the DNA damage response were also observed with SMN depletion in human SH-SY5Y neuroblastoma cells and human induced pluripotent stem cell-derived motor neurons. We also found that retained introns, high in GC content, served as substrates for the formation of transcriptional R-loops. We propose that defects in intron removal in SMA promote DNA damage in part through the formation of RNA:DNA hybrid structures, leading to motor neuron death. PMID:28270613

Prevalence, course and determinants of carpal tunnel syndrome symptoms during pregnancy: a prospective study.

PubMed

Meems, M; Truijens, Sem; Spek, V; Visser, L H; Pop, V J M

2015-07-01

To investigate the prevalence, severity and relation to fluid retention of self-reported pregnancy-related carpal tunnel syndrome (CTS) symptoms in a large sample of pregnant women. A prospective longitudinal cohort study. Dutch women who became pregnant between January 2013 and January 2014 in the southeast of The Netherlands. A total of 639 Dutch pregnant women. Baseline characteristics were assessed at 12 weeks' gestation. CTS symptoms were assessed using the Boston Carpal Tunnel Questionnaire (BCTQ) at 32 weeks and during the first postpartum week regarding the last weeks of pregnancy. Fluid retention, sleeping problems and depressive symptoms (using the Edinburgh Depression Scale) were assessed at several time points during pregnancy. BCTQ scores, fluid retention and sleeping problems. Of the 639 women, 219 (34%) reported CTS symptoms during pregnancy. Total mean scores on the BCTQ were significantly higher after 32 weeks' than up to 32 weeks' gestation. Most women experienced mild to moderate symptoms. Pregnant women with CTS symptoms reported significantly higher levels of fluid retention during gestation compared with pregnant women without CTS symptoms [F = 60.6, df (1598), P < 0.001], adjusted for body mass index (BMI), age, parity, and depression scores. Higher scores on fluid retention throughout the pregnancy were significantly related to CTS (OR = 1.8, 95%CI 1.5, 2.1, P < 0.001). Finally, the occurrence of CTS was independently related to sleeping problems. Although the severity of symptoms and functional impairment of CTS were relatively mild, health care professionals should be aware of the high prevalence. The occurrence of CTS symptoms is significantly higher in women who report fluid retention during gestation and it can contribute to sleeping problems. © 2015 Royal College of Obstetricians and Gynaecologists.

Retention of urine in anogenital herpetic infection.

PubMed

Oates, J K; Greenhouse, P R

1978-04-01

In 17 patients, 15 women and 2 men, acute retention of urine developed in association with an attack of anogenital herpes. Constipation, blunting of sensation over the 2nd and 3rd sacral dermatomes, and neuralgic pains in the same area (with absence of the bulbocavernosus reflex in some individuals) suggested localised lumbosacral meningomyelitis with involvement of mainly sacral-nerve roots. The urinary dysfunction persisted on average for ten days and in 4 patients was severe enough to warrant catheterisation. Anogenital herpes should always be considered as a possible cause of acute retention of urine in sexually active young people and the possibility of occult herpetic infection of the cervix and rectum should be investigated.

Fluid handling equipment: A compilation

NASA Technical Reports Server (NTRS)

1976-01-01

Devices and techniques used in fluid-handling and vacuum systems are described. Section 1 presents several articles on fluid lines and tubing. Section 2 describes a number of components such as valves, filters, and regulators. The last section contains descriptions of a number of innovative fluid-handling systems.

A percutaneous drainage protocol for severe and moderately severe acute pancreatitis.

PubMed

Sugimoto, Motokazu; Sonntag, David P; Flint, Greggory S; Boyce, Cody J; Kirkham, John C; Harris, Tyler J; Carr, Sean M; Nelson, Brent D; Barton, Joshua G; Traverso, L William

2015-11-01

According to the revised Atlanta classification, severe and moderately severe acute pancreatitis (AP) includes patients with pancreatic and peripancreatic collections with or without organ failure. These collections suggest the presence of pancreatic juice leakage. The aim of this study was to evaluate the efficacy of a percutaneous catheter drainage (PCD) protocol designed to control leakage and decrease disease severity. Among 663 patients with clinical AP, 122 were classified as moderately severe or severe AP (all had collections). The computed tomography severity index (CTSI) score was calculated. The indication for PCD was based on progressive clinical signs and symptoms. Drain patency, position, and need for additional drainage sites were assessed using CT scans and drain studies initially every 3 days using a proactive protocol. Drain fluid was examined for amylase concentration and microbiological culture. Clinicopathological variables for patients with and without PCD were compared. Since there was no mortality, we used prolonged drainage time to measure the success of PCD. Within the group treated with PCD, variables that resulted in prolonged drainage time were analyzed. PCD was used in 47/122 (39 %) patients of which 33/47 (70 %) had necrosis. PCD cases had a median CTSI of 8 and were classified as moderately severe AP (57 %) and severe AP (43 %). Inhospital mortality was zero. Surgical necrosectomy was not required for patients with necrosis. Independent risk factors for prolonged drainage time were persistent organ failure >48 h (P = 0.001), CTSI 8-10 (P = 0.038), prolonged duration of amylase-rich fluid in drains (P < 0.001), and polymicrobial culture fluid in drains (P = 0.015). A proactive PCD protocol persistently maintaining drain patency advanced to the site of leak controlled the prolonged amylase in drainage fluid resulting in a mortality rate of zero.

Workforce Challenges and Retention Success Stories

NASA Technical Reports Server (NTRS)

Donohue, John T.

2008-01-01

This viewgraph document discusses the current and future challenges in building and retaining the required workforce of scientist and engineers for NASA. Specifically, the talk reviews the current situation at the Goddard Space Flight Center in Greenbelt, Maryland. Several programs at NASA for high school and college students to assist in inspiring the next generation of scientist and engineers are reviewed. The issue of retention of the best of the young scientists and engineers is also reviewed, with a brief review of several young engineers and their success with and for NASA.

Study of blood flow in several benchmark micro-channels using a two-fluid approach.

PubMed

Wu, Wei-Tao; Yang, Fang; Antaki, James F; Aubry, Nadine; Massoudi, Mehrdad

2015-10-01

It is known that in a vessel whose characteristic dimension (e.g., its diameter) is in the range of 20 to 500 microns, blood behaves as a non-Newtonian fluid, exhibiting complex phenomena, such as shear-thinning, stress relaxation, and also multi-component behaviors, such as the Fahraeus effect, plasma-skimming, etc. For describing these non-Newtonian and multi-component characteristics of blood, using the framework of mixture theory, a two-fluid model is applied, where the plasma is treated as a Newtonian fluid and the red blood cells (RBCs) are treated as shear-thinning fluid. A computational fluid dynamic (CFD) simulation incorporating the constitutive model was implemented using OpenFOAM® in which benchmark problems including a sudden expansion and various driven slots and crevices were studied numerically. The numerical results exhibited good agreement with the experimental observations with respect to both the velocity field and the volume fraction distribution of RBCs.

Study of blood flow in several benchmark micro-channels using a two-fluid approach

PubMed Central

Wu, Wei-Tao; Yang, Fang; Antaki, James F.; Aubry, Nadine; Massoudi, Mehrdad

2015-01-01

It is known that in a vessel whose characteristic dimension (e.g., its diameter) is in the range of 20 to 500 microns, blood behaves as a non-Newtonian fluid, exhibiting complex phenomena, such as shear-thinning, stress relaxation, and also multi-component behaviors, such as the Fahraeus effect, plasma-skimming, etc. For describing these non-Newtonian and multi-component characteristics of blood, using the framework of mixture theory, a two-fluid model is applied, where the plasma is treated as a Newtonian fluid and the red blood cells (RBCs) are treated as shear-thinning fluid. A computational fluid dynamic (CFD) simulation incorporating the constitutive model was implemented using OpenFOAM® in which benchmark problems including a sudden expansion and various driven slots and crevices were studied numerically. The numerical results exhibited good agreement with the experimental observations with respect to both the velocity field and the volume fraction distribution of RBCs. PMID:26240438

The Effects of Spatial Visualization Skill Training on Gender and Retention in Engineering.

ERIC Educational Resources Information Center

Devon, Richard; Engel, Renata; Turner, Geoffrey

1998-01-01

Engineering students were given a mental rotation test at the beginning and end of their first-year engineering course and again several years later to assess the relationship between spatial visualization skill and retention in engineering. No relationship was found between task scores and retention; however, a course in design and graphics…

Retention of Homeless Smokers in the Power to Quit Study.

PubMed

Richards, Christina M; Sharif, Faduma; Eischen, Sara; Thomas, Janet; Wang, Qi; Guo, Hongfei; Luo, Xianghua; Okuyemi, Kolawole

2015-09-01

Concerns about retention are a major barrier to conducting studies enrolling homeless individuals. Since smoking is a major problem in homeless communities and research on effective methods of promoting smoking cessation is needed, we describe strategies used to increase retention and participant characteristics associated with retention in smoking cessation study enrolling homeless adults. The parent study was a 2-group randomized controlled trial with 26-week follow-up enrolling 430 homeless smokers from emergency shelters and transitional housing units in Minneapolis/Saint Paul, MN, USA. Multiple strategies were used to increase retention, including conducting visits at convenient locations for participants, collecting several forms of contact information from participants, using a schedule that was flexible and included frequent low-intensity visits, and providing incentives. Participant demographics as well as characteristics related to tobacco and drug use and health status were analyzed for associations with retention using univariate and multivariate analysis. Overall retention was 75% at 26 weeks. Factors associated with increased retention included greater age; having healthcare coverage; history of multiple homeless episodes, lower stress level; and higher PHQ-9 (Patient Health Questionnaire-9) score. A history of excessive drinking and drug use were associated with decreased retention. It is possible to successfully retain homeless individuals in a smoking cessation study if the study is designed with participants' needs in mind. © The Author 2014. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

In vivo optical imaging of the viable epidermis around the nailfold capillaries for the assessment of heart failure severity in humans.

PubMed

Shirshin, Evgeny A; Gurfinkel, Yury I; Matskeplishvili, Simon T; Sasonko, Maria L; Omelyanenko, Nikolai P; Yakimov, Boris P; Lademann, Juergen; Darvin, Maxim E

2018-05-29

Heart failure is among the socially significant diseases, involving over 2% of the adult population in the developed countries. Diagnostics of the HF severity remains complicated due to the absence of specific symptoms and objective criteria. Here we present an indicator of the HF severity based on the imaging tissue parameters around the nailfold capillaries. High resolution nailfold video capillaroscopy was performed to determine the perivascular zone (PZ) size around nailfold capillaries, and two-photon tomography with fluorescence lifetime imaging was used to investigate PZ composition. We found that the size of PZ around the nailfold capillaries strongly correlates with heart failure severity. Further investigations using two-photon tomography demonstrated that PZ corresponds to the border of viable epidermis and it was suggested that the PZ size variations were due to the different amounts of interstitial fluid that potentially further translates in clinically significant oedema. The obtained results allow for the development of a quantitative indicator of oedematous syndrome, which can be used in various applications to monitor the dynamics of interstitial fluid retention. We therefore suggest PZ size measured with nailfold video capillaroscopy as a novel quantitative sensitive non-invasive marker of heart failure severity. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Boulder Valley Kindergarten Study: Retention Practices and Retention Effects.

ERIC Educational Resources Information Center

Shepard, Lorrie A.; Smith, Mary Lee

Having implemented a policy that allowed schools to retain children in kindergarten an extra year, the Boulder Valley Public School District in Colorado conducted a study to determine the cognitive and emotional benefits of retention in kindergarten and the characteristics that led to decisions about retention. The study involved a research review…

Reimagining the Retention Problem: Moving Our Thinking from End-Product to By-Product

ERIC Educational Resources Information Center

Siegel, Michael J.

2011-01-01

Over the past several decades, college-student retention has arguably been the most intensely studied issue in academe. Though the body of retention literature grows ever larger, no one model adequately explains the process by which college students make a decision to leave an institution or to persist to graduation. And while no magic bullet…

Passenger fluid volumes measured before and after a prolonged commercial jet flight.

NASA Technical Reports Server (NTRS)

Johnson, P. C.; Carpentier, W. R.; Driscoll, T. B.; Lapinta, C. K.; Rummel, J. A.; Sawin, C. F.

1972-01-01

Interstitial and intracellular fluid volumes were calculated from measured plasma volume, extracellular volume and total body water of six subjects before and after a 24-hour commercial overseas flight. No change occurred in these spaces or in peripheral hematocrit or total serum protein concentration. The subjective feeling of dehydration and the actual swelling of the lower extremities characteristically found among passengers at the end of a long trip of this type seems to represent a shift in body fluids to the dependent portions of the body rather than water retention or a decrease in the intravascular water volume.

The role of heterogeneous fluid pressures in the shape of critical-taper submarine wedges, with application to Barbados

NASA Astrophysics Data System (ADS)

Yeh, En-Chao; Suppe, John

2014-05-01

Some classic accretionary wedges such as Nankai trough and Barbados are mechanically heterogeneous based on their spatial variation in taper, showing inward decrease in surface slope α without covariation in detachment dip β. Possible sources of regional heterogeniety include variation in fluid pressure, density, cohesion and fault strength, which can be constrained by the seismic or borehole observable parameter, fluid-retention depth Z_FRD, below which compaction is strongly diminished. In particular the Hubbert-Rubey fluid-pressure weakening can be addressed as (1-lambda)~0.6Z_FRD/Z. We recast the heterogeneous critical-taper wedge theory of Dahlen (1990) in terms of the observable Z_FRD/H, where H is the detachment depth, which allows for real world applications. For example, seismic velocity and borehole data from the Barbados shows that the fluid-retention depth Z_FRD is approximately constant and Z_FRD/H decreases inward. This leads to a factor of four inward decreases in wedge strength, dominated by fluid pressure, with only a second-order role for density and cohesion. An inward decrease in wedge strength should by itself produce an increase in taper, therefore the observed decreasing taper must be dominated by decreasing fault strength mu_b* from 0.03 to 0.01. Static fluid-pressures along the detachment in equilibrium with the overlying wedge predict the observed wedge geometry well, given a constant intrinsic friction coefficient mu_b=0.15.

Actual drawing of histological images improves knowledge retention.

PubMed

Balemans, Monique C M; Kooloos, Jan G M; Donders, A Rogier T; Van der Zee, Catharina E E M

2016-01-01

Medical students have to process a large amount of information during the first years of their study, which has to be retained over long periods of nonuse. Therefore, it would be beneficial when knowledge is gained in a way that promotes long-term retention. Paper-and-pencil drawings for the uptake of form-function relationships of basic tissues has been a teaching tool for a long time, but now seems to be redundant with virtual microscopy on computer-screens and printers everywhere. Several studies claimed that, apart from learning from pictures, actual drawing of images significantly improved knowledge retention. However, these studies applied only immediate post-tests. We investigated the effects of actual drawing of histological images, using randomized cross-over design and different retention periods. The first part of the study concerned esophageal and tracheal epithelium, with 384 medical and biomedical sciences students randomly assigned to either the drawing or the nondrawing group. For the second part of the study, concerning heart muscle cells, students from the previous drawing group were now assigned to the nondrawing group and vice versa. One, four, and six weeks after the experimental intervention, the students were given a free recall test and a questionnaire or drawing exercise, to determine the amount of knowledge retention. The data from this study showed that knowledge retention was significantly improved in the drawing groups compared with the nondrawing groups, even after four or six weeks. This suggests that actual drawing of histological images can be used as a tool to improve long-term knowledge retention. © 2015 American Association of Anatomists.

Magnetic Fluids--Part 2.

ERIC Educational Resources Information Center

Hoon, S. B.; Tanner, B. K.

1985-01-01

Continues a discussion of magnetic fluids by providing background information on and procedures for conducting several demonstrations. Indicates that, with a little patience and ingenuity, only modest magnetic fields and about 20 ml of low-viscosity, commercial magnetite-water-based magnetic fluid are required. (JN)

Elsberg syndrome: a neurologic basis for acute urinary retention in patients with genital herpes.

PubMed

Hemrika, D J; Schutte, M F; Bleker, O P

1986-09-01

Three patients with genital herpes simplex type II primoinfection and acute urinary retention are described. All patients showed pleocytosis of the cerebrospinal fluid, substantiating central nervous involvement. The association of genital herpes and sacral (myelo-) radiculitis has gained little attention in gynecologic literature, yet it is not an uncommon finding in female patients suffering from herpes. The present report emphasizes the importance of urinary symptoms in genital herpes and reviews the literature on similar cases.

Effect of ceramic membrane channel diameter on limiting retentate protein concentration during skim milk microfiltration.

PubMed

Adams, Michael C; Barbano, David M

2016-01-01

Our objective was to determine the effect of retentate flow channel diameter (4 or 6mm) of nongraded permeability 100-nm pore size ceramic membranes operated in nonuniform transmembrane pressure mode on the limiting retentate protein concentration (LRPC) while microfiltering (MF) skim milk at a temperature of 50°C, a flux of 55 kg · m(-2) · h(-1), and an average cross-flow velocity of 7 m · s(-1). At the above conditions, the retentate true protein concentration was incrementally increased from 7 to 11.5%. When temperature, flux, and average cross-flow velocity were controlled, ceramic membrane retentate flow channel diameter did not affect the LRPC. This indicates that LRPC is not a function of the Reynolds number. Computational fluid dynamics data, which indicated that both membranes had similar radial velocity profiles within their retentate flow channels, supported this finding. Membranes with 6-mm flow channels can be operated at a lower pressure decrease from membrane inlet to membrane outlet (ΔP) or at a higher cross-flow velocity, depending on which is controlled, than membranes with 4-mm flow channels. This implies that 6-mm membranes could achieve a higher LRPC than 4-mm membranes at the same ΔP due to an increase in cross-flow velocity. In theory, the higher LRPC of the 6-mm membranes could facilitate 95% serum protein removal in 2 MF stages with diafiltration between stages if no serum protein were rejected by the membrane. At the same flux, retentate protein concentration, and average cross-flow velocity, 4-mm membranes require 21% more energy to remove a given amount of permeate than 6-mm membranes, despite the lower surface area of the 6-mm membranes. Equations to predict skim milk MF retentate viscosity as a function of protein concentration and temperature are provided. Retentate viscosity, retentate recirculation pump frequency required to maintain a given cross-flow velocity at a given retentate viscosity, and retentate protein

A simple approximation for larval retention around reefs

NASA Astrophysics Data System (ADS)

Cetina-Heredia, Paulina; Connolly, Sean R.

2011-09-01

Estimating larval retention at individual reefs by local scale three-dimensional flows is a significant problem for understanding, and predicting, larval dispersal. Determining larval dispersal commonly involves the use of computationally demanding and expensively calibrated/validated hydrodynamic models that resolve reef wake eddies. This study models variation in larval retention times for a range of reef shapes and circulation regimes, using a reef-scale three-dimensional hydrodynamic model. It also explores how well larval retention time can be estimated based on the "Island Wake Parameter", a measure of the degree of flow turbulence in the wake of reefs that is a simple function of flow speed, reef dimension, and vertical diffusion. The mean residence times found in the present study (0.48-5.64 days) indicate substantial potential for self-recruitment of species whose larvae are passive, or weak swimmers, for the first several days after release. Results also reveal strong and significant relationships between the Island Wake Parameter and mean residence time, explaining 81-92% of the variability in retention among reefs across a range of unidirectional flow speeds and tidal regimes. These findings suggest that good estimates of larval retention may be obtained from relatively coarse-scale characteristics of the flow, and basic features of reef geomorphology. Such approximations may be a valuable tool for modeling connectivity and meta-population dynamics over large spatial scales, where explicitly characterizing fine-scale flows around reef requires a prohibitive amount of computation and extensive model calibration.

Measuring faculty retention and success in academic medicine.

PubMed

Ries, Andrew; Wingard, Deborah; Gamst, Anthony; Larsen, Catherine; Farrell, Elizabeth; Reznik, Vivian

2012-08-01

To develop and demonstrate the usefulness of quantitative methods for assessing retention and academic success of junior faculty in academic medicine. The authors created matched sets of participants and nonparticipants in a junior faculty development program based on hire date and academic series for newly hired assistant professors at the University of California, San Diego (UCSD), School of Medicine between 1988 and 2005. They used Kaplan-Meier and Cox proportional hazards survival analyses to characterize the influence of covariates, including gender, ethnicity, and program participation, on retention. They also developed a new method for quantifying academic success based on several measures including (1) leadership and professional activities, (2) honors and awards, (3) research grants, (4) teaching and mentoring/advising activities, and (5) publications. The authors then used these measures to compare matched pairs of participating and nonparticipating faculty who were subsequently promoted and remained at UCSD. Compared with matched nonparticipants, the retention of junior faculty who participated in the faculty development program was significantly higher. Among those who were promoted and remained at UCSD, the academic success of faculty development participants was consistently greater than that of matched nonparticipants. This difference reached statistical significance for leadership and professional activities. Using better quantitative methods for evaluating retention and academic success will improve understanding and research in these areas. In this study, use of such methods indicated that organized junior faculty development programs have positive effects on faculty retention and may facilitate success in academic medicine.

The role of transpapillary drainage in management of patients with pancreatic fluid collections and pancreatic duct disruption as a consequences of severe acute pancreatitis.

PubMed

Jagielski, Mateusz; Smoczyński, Marian; Adrych, Krystian

In last thirty years we have been observing significant development of an endoscopic treatment of pancreatic fluid collections, including transmural drainage of walled-off pancreatic necrosis. Simultaneously, the use of endotherapy in treatment of main pancreatic ducts disruptions has increased. Despite many publications available in current literature, concerning the endoscopic treatment of consequences of acute necrotizing pancreatitis, the role of transpapillary drainage in management of patients with pancreatic fluid collections and pancreatic duct disruption as an after-effect of severe acute pancreatitis remains unclear and is still a current problem. This publication includes comment on the article entitled 'Early dual drainage combining transpapillary endotherapy and percutaneous catheter drainage in patients with pancreatic fistula associated with severe acute pancreatitis' published by Yokoi et al. in the July-August 2016 issue of Pancreatology together with questions to the authors. Furthermore, in the article we did pay particular attention to the role of transpapillary drainage in management of pancreatic fluid collections, especially of walled-of pancreatic necrosis. Copyright © 2016 IAP and EPC. Published by Elsevier B.V. All rights reserved.

Fall 1982 Retention Study.

ERIC Educational Resources Information Center

Peralta Community Coll. District, Oakland, CA. Office of Research, Planning and Development.

In fall 1982, a study was conducted in the Peralta Community College District (PCCD) using withdrawal and grade distribution data to analyze student retention patterns. Successful retention rates were based on the percentage of students who received a passing grade, while total retention rates were based on the percentage of students who received…

Effect of hydrofracking fluid on colloid transport in the unsaturated zone.

PubMed

Sang, Wenjing; Stoof, Cathelijne R; Zhang, Wei; Morales, Verónica L; Gao, Bin; Kay, Robert W; Liu, Lin; Zhang, Yalei; Steenhuis, Tammo S

2014-07-15

Hydraulic fracturing is expanding rapidly in the US to meet increasing energy demand and requires high volumes of hydrofracking fluid to displace natural gas from shale. Accidental spills and deliberate land application of hydrofracking fluids, which return to the surface during hydrofracking, are common causes of environmental contamination. Since the chemistry of hydrofracking fluids favors transport of colloids and mineral particles through rock cracks, it may also facilitate transport of in situ colloids and associated pollutants in unsaturated soils. We investigated this by subsequently injecting deionized water and flowback fluid at increasing flow rates into unsaturated sand columns containing colloids. Colloid retention and mobilization was measured in the column effluent and visualized in situ with bright field microscopy. While <5% of initial colloids were released by flushing with deionized water, 32-36% were released by flushing with flowback fluid in two distinct breakthrough peaks. These peaks resulted from 1) surface tension reduction and steric repulsion and 2) slow kinetic disaggregation of colloid flocs. Increasing the flow rate of the flowback fluid mobilized an additional 36% of colloids, due to the expansion of water filled pore space. This study suggests that hydrofracking fluid may also indirectly contaminate groundwater by remobilizing existing colloidal pollutants.

Effect of Hydrofracking Fluid on Colloid Transport in the Unsaturated Zone

PubMed Central

2014-01-01

Hydraulic fracturing is expanding rapidly in the US to meet increasing energy demand and requires high volumes of hydrofracking fluid to displace natural gas from shale. Accidental spills and deliberate land application of hydrofracking fluids, which return to the surface during hydrofracking, are common causes of environmental contamination. Since the chemistry of hydrofracking fluids favors transport of colloids and mineral particles through rock cracks, it may also facilitate transport of in situ colloids and associated pollutants in unsaturated soils. We investigated this by subsequently injecting deionized water and flowback fluid at increasing flow rates into unsaturated sand columns containing colloids. Colloid retention and mobilization was measured in the column effluent and visualized in situ with bright field microscopy. While <5% of initial colloids were released by flushing with deionized water, 32–36% were released by flushing with flowback fluid in two distinct breakthrough peaks. These peaks resulted from 1) surface tension reduction and steric repulsion and 2) slow kinetic disaggregation of colloid flocs. Increasing the flow rate of the flowback fluid mobilized an additional 36% of colloids, due to the expansion of water filled pore space. This study suggests that hydrofracking fluid may also indirectly contaminate groundwater by remobilizing existing colloidal pollutants. PMID:24905470

Determination of nitrate in biological fluids by HPLC.

PubMed

Ashraf, Muhammad; Ghalloo, Bilal Ahmed; Hayat, Muhammad Munawar; Rahman, Jameel; Ejaz, Samina; Iqbal, Muhammad; -Nasim, Faizul Hassan

2017-01-01

Nitrate is the stable product of nitric oxide, which is physiologically active radical, an immunomodulator and a neuromodulator; its quantification in biological fluids is important to study the physiological and biochemical nature. Therefore, the purpose of this study was to quantify nitrate in different biological fluids like serum, cerebrospinal fluid (CSF) and ascetic fluid (ASF) using HPLC technique. A new HPLC method for the estimation of nitrate in serum, CSF and ASF was developed using the mobile phase of 1.0mM each of Na 2 CO 3 and NaHCO 3 (1:1, v/v, pH 5 with H 3 PO 4 ) at a flow rate of 1.0mLmin -1 . Eluate was detected at 220nm with the retention time of nitrate 2.55 min. The LOD and LOQ values of nitrate were 0.03μgmL -1 and 0.098μgmL -1 , respectively. Nitrate was eluted through SAX Hypersil column of 150 × 4.6mm, id, 5μm particle size. Run time was 10min. The method was validated according to the FDA guidelines and was found linear in the range of 0.39 to 50μgmL -1 and CV was <3%, within limits of FDA guidelines. The method was used successfully for the estimation of nitrate in biological fluids like serum, CSF and ASF of 20 patients each. This is an alternate and reproducible method for the detection of nitrates in biological fluids.

Institutionalization: A Model of Retention Through Student Engagement

NASA Astrophysics Data System (ADS)

Davis, E. J.; Campbell, A.; Strand, D.

2005-12-01

Bowie State University and NASA Goddard Space Flight Center have, for the past 10 years, worked diligently together to enhance the science, mathematics, engineering and technology (SMET) domain. Efforts made because of a Model Institutions for Excellence (MIE) Award have changed the landscape of the SMET domain by increasing the retention and graduation rates, the number of students entering graduate and professional schools, and the number of students entering SMET related careers. Several initiatives - a Scholarship program, PRISEM Tutoring Center, Safenet Program, Research Emphasis, Focused Mentoring, a Summer Academy for accepted and enrolled incoming students, a Bridge Program for students needing assistance being admitted to the University, the RISE Program and the Bowie State Satellite Operations and Control Center - provides the nurturing and mentoring focus, and opportunities that have resulted in a retention rate of approximately 80%, a 40% increase in the graduation rate, and an 85% increase in the number of students interested/entering graduate school. Successes that have documented by various assessment activities have led to the institutionalization of the retention model of the MIE Initiative. It is anticipated that University-wide application of the retention model will provide the incentives necessary to obtain similar results as has the MIE Initiative.

Intraoperative Fluids and Fluid Management for Ambulatory Dental Sedation and General Anesthesia.

PubMed

Saraghi, Mana

2015-01-01

Intravenous fluids are administered in virtually every parenteral sedation and general anesthetic. The purpose of this article is to review the physiology of body-water distribution and fluid dynamics at the vascular endothelium, evaluation of fluid status, calculation of fluid requirements, and the clinical rationale for the use of various crystalloid and colloid solutions. In the setting of elective dental outpatient procedures with minor blood loss, isotonic balanced crystalloid solutions are the fluids of choice. Colloids, on the other hand, have no use in outpatient sedation or general anesthesia for dental or minor oral surgery procedures but may have several desirable properties in long and invasive maxillofacial surgical procedures where advanced hemodynamic monitoring may assess the adequacy of intravascular volume.

Driver retention strategy : the role of a career path

DOT National Transportation Integrated Search

2000-03-01

The voluntary turnover rate among truckload carriers, at 50-100 percent, is excessive when compared to other industries. The turnover rate has been known to exceed 150 percent. It is believed that are several factors are involved in this retention pr...

Personalised fluid resuscitation in the ICU: still a fluid concept?

PubMed

van Haren, Frank

2017-12-28

The administration of intravenous fluid to critically ill patients is one of the most common, but also one of the most fiercely debated, interventions in intensive care medicine. Even though many thousands of patients have been enrolled in large trials of alternative fluid strategies, consensus remains elusive and practice is widely variable. Critically ill patients are significantly heterogeneous, making a one size fits all approach unlikely to be successful.New data from basic, animal, and clinical research suggest that fluid resuscitation could be associated with significant harm. There are several important limitations and concerns regarding fluid bolus therapy as it is currently being used in clinical practice. These include, but are not limited to: the lack of an agreed definition; limited and short-lived physiological effects; no evidence of an effect on relevant patient outcomes; and the potential to contribute to fluid overload, specifically when fluid responsiveness is not assessed and when targets and safety limits are not used.Fluid administration in critically ill patients requires clinicians to integrate abnormal physiological parameters into a clinical decision-making model that also incorporates the likely diagnosis and the likely risk or benefit in the specific patient's context. Personalised fluid resuscitation requires careful attention to the mnemonic CIT TAIT: context, indication, targets, timing, amount of fluid, infusion strategy, and type of fluid.The research agenda should focus on experimental and clinical studies to: improve our understanding of the physiological effects of fluid infusion, e.g. on the glycocalyx; evaluate new types of fluids; evaluate novel fluid minimisation protocols; study the effects of a no-fluid strategy for selected patients and scenarios; and compare fluid therapy with other interventions. The adaptive platform trial design may provide us with the tools to evaluate these types of interventions in the intrinsically

Sonographic findings in acute urinary retention secondary to retroverted gravid uterus: pathophysiology and preventive measures.

PubMed

Yang, J-M; Huang, W-C

2004-05-01

To explore the pathophysiology of acute urinary retention in women with a retroverted gravid uterus and to suggest measures to prevent its recurrence. In five women with a retroverted gravid uterus and acute urinary retention necessitating catheterization, the morphology of the genitourinary system was assessed by using transabdominal, transvaginal and introital sonography. In the supine resting position, the cervix was displaced superiorly and anteriorly by the impacted and retroverted uterus so that it compressed the lower bladder, leading to obstruction of the internal urethral orifice. The upper bladder extended superiorly and overlay the uterus. During straining, urethral motion was not limited and there was an average rotational angle of the bladder neck of 32 degrees, ranging from 21 degrees to 44 degrees. Increasing abdominal pressure further compressed the lower bladder. Measures suggested to the women for the prevention of urinary retention included limiting fluid intake before sleep, changing from the supine to the prone position before getting up and avoiding a Valsalva maneuver but performing a Credé maneuver during voiding. In all except one case these measures successfully prevented recurrence. Acute urinary retention secondary to a retroverted gravid uterus is caused by a displaced cervix compressing the lower bladder and interfering with drainage to the urethra. The urethra itself is not compressed or distorted. Understanding the pathophysiology of the lower urinary tract may allow maneuvers which prevent acute urinary retention. Copyright 2004 ISUOG. Published by John Wiley & Sons, Ltd.

Metalworking and machining fluids

DOEpatents

Erdemir, Ali; Sykora, Frank; Dorbeck, Mark

2010-10-12

Improved boron-based metal working and machining fluids. Boric acid and boron-based additives that, when mixed with certain carrier fluids, such as water, cellulose and/or cellulose derivatives, polyhydric alcohol, polyalkylene glycol, polyvinyl alcohol, starch, dextrin, in solid and/or solvated forms result in improved metalworking and machining of metallic work pieces. Fluids manufactured with boric acid or boron-based additives effectively reduce friction, prevent galling and severe wear problems on cutting and forming tools.

Urinary retention and post-void residual urine in men: separating truth from tradition.

PubMed

Kaplan, Steven A; Wein, Alan J; Staskin, David R; Roehrborn, Claus G; Steers, William D

2008-07-01

The definitions of acute and chronic urinary retention remain empirical and subject to wide interpretation. Standardized criteria have not been established and many questions remain unanswered. Moreover, the definition of significant post-void residual urine is unclear. We reviewed several aspects of urinary retention that require clarification with the objective of stimulating discussion among urologists to establish an accurate and coherent definition of urinary retention and significant post-void residual urine, and clarify risk factors. A MEDLINE search for articles written in English and published before April 2007 was done using a list of terms related to urinary retention. Articles not directly relevant to urinary retention or post-void residual urine were excluded. The term urinary retention lacks precise clinical or urodynamic meaning. Use of this term to describe a symptom, a sign, and a condition further complicates the issue. Many factors can contribute to the development of retention, including bladder outlet obstruction, detrusor underactivity, and neurogenic bladder conditions. Community based studies and clinical trials in patients with benign prostatic enlargement and/or lower urinary tract symptoms yield different estimates of the incidence of retention and only provide information on the epidemiology of acute urinary retention. However, age, previous retention episodes, lower urinary tract symptoms, chronic inflammation, serum prostate specific antigen level, prostate size, and urodynamic variables appear to be predictors of acute urinary retention. Alpha-receptor antagonists and 5alpha-reductase inhibitors may be useful in preventing urinary retention episodes and progressive benign prostatic enlargement. Clinical trials on the short-term use of antimuscarinics have not provided evidence that these agents increase the risk of retention; data on longer term administration are needed. Clinicians are adopting less invasive approaches (eg

Voluntary fluid intake and core temperature responses in adolescent tennis players: sports beverage versus water.

PubMed

Bergeron, M F; Waller, J L; Marinik, E L

2006-05-01

To examine differences in ad libitum fluid intake, comparing a 6% carbohydrate/electrolyte drink (CHO-E) and water, and associated differences in core temperature and other selected physiological and perceptual responses in adolescent athletes during tennis training in the heat. Fourteen healthy, fit, young tennis players (nine male; five female; mean (SD) age 15.1 (1.4) years; weight 60.6 (8.3) kg; height 172.8 (8.6) cm) completed two 120 minute tennis specific training sessions on separate days (randomised, crossover design) in a warm environment (wet bulb globe temperature: CHO-E, 79.3 (2.6) degrees F; water, 79.9 (2.2) degrees F; p>0.05). There were no significant differences (p>0.05) between the trials with respect to fluid intake, urine volume, fluid retention, sweat loss, perceived exertion, thirst, or gastrointestinal discomfort. However, there was a difference (p<0.05) in the percentage body weight change after training (CHO-E, -0.5 (0.7)%; water, -0.9 (0.6)%). Urine specific gravity before training (CHO-E, 1.024 (0.006); water, 1.025 (0.005)) did not correlate significantly (p>0.05) with any of these measurements or with core body temperature. In examining the main effect for trial, the CHO-E trial showed a significantly lower (p<0.001) mean body temperature (irrespective of measurement time) than the water trial. However, the mean body temperature in each trial was not associated (p>0.05) with fluid intake, fluid retention, sweat loss, or percentage body weight change. Ad libitum consumption of a CHO-E drink may be more effective than water in minimising fluid deficits and mean core temperature responses during tennis and other similar training in adolescent athletes.

Simplified tools for measuring retention in care in antiretroviral treatment program in Ethiopia: cohort and current retention in care.

PubMed

Assefa, Yibeltal; Worku, Alemayehu; Wouters, Edwin; Koole, Olivier; Haile Mariam, Damen; Van Damme, Wim

2012-01-01

Patient retention in care is a critical challenge for antiretroviral treatment programs. This is mainly because retention in care is related to adherence to treatment and patient survival. It is therefore imperative that health facilities and programs measure patient retention in care. However, the currently available tools, such as Kaplan Meier, for measuring retention in care have a lot of practical limitations. The objective of this study was to develop simplified tools for measuring retention in care. Retrospective cohort data were collected from patient registers in nine health facilities in Ethiopia. Retention in care was the primary outcome for the study. Tools were developed to measure "current retention" in care during a specific period of time for a specific "ART-age group" and "cohort retention" in care among patients who were followed for the last "Y" number of years on ART. "Probability of retention" based on the tool for "cohort retention" in care was compared with "probability of retention" based on Kaplan Meier. We found that the new tools enable to measure "current retention" and "cohort retention" in care. We also found that the tools were easy to use and did not require advanced statistical skills. Both "current retention" and "cohort retention" are lower among patients in the first two "ART-age groups" and "ART-age cohorts" than in subsequent "ART-age groups" and "ART-age cohorts". The "probability of retention" based on the new tools were found to be similar to the "probability of retention" based on Kaplan Meier. The simplified tools for "current retention" and "cohort retention" will enable practitioners and program managers to measure and monitor rates of retention in care easily and appropriately. We therefore recommend that health facilities and programs start to use these tools in their efforts to improve retention in care and patient outcomes.

Pulmonary instillation of low doses of titanium dioxide nanoparticles in mice leads to particle retention and gene expression changes in the absence of inflammation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Husain, Mainul, E-mail: mainul.husain@hc-sc.gc.ca; Saber, Anne T., E-mail: ats@nrcwe.dk; Guo, Charles, E-mail: charles.guo@hc-sc.gc.ca

2013-06-15

We investigated gene expression, protein synthesis, and particle retention in mouse lungs following intratracheal instillation of varying doses of nano-sized titanium dioxide (nano-TiO{sub 2}). Female C57BL/6 mice were exposed to rutile nano-TiO{sub 2} via single intratracheal instillations of 18, 54, and 162 μg/mouse. Mice were sampled 1, 3, and 28 days post-exposure. The deposition of nano-TiO{sub 2} in the lungs was assessed using nanoscale hyperspectral microscopy. Biological responses in the pulmonary system were analyzed using DNA microarrays, pathway-specific real-time RT-PCR (qPCR), gene-specific qPCR arrays, and tissue protein ELISA. Hyperspectral mapping showed dose-dependent retention of nano-TiO{sub 2} in the lungs upmore » to 28 days post-instillation. DNA microarray analysis revealed approximately 3000 genes that were altered across all treatment groups (± 1.3 fold; p < 0.1). Several inflammatory mediators changed in a dose- and time-dependent manner at both the mRNA and protein level. Although no influx of neutrophils was detected at the low dose, changes in the expression of several genes and proteins associated with inflammation were observed. Resolving inflammation at the medium dose, and lack of neutrophil influx in the lung fluid at the low dose, were associated with down-regulation of genes involved in ion homeostasis and muscle regulation. Our gene expression results imply that retention of nano-TiO{sub 2} in the absence of inflammation over time may potentially perturb calcium and ion homeostasis, and affect smooth muscle activities. - Highlights: • Pulmonary effects following exposure to low doses of nano-TiO{sub 2} were examined. • Particle retention in lungs was assessed using nanoscale hyperspectral microscopy. • Particles persisted up to 28 days in lungs in all dose groups. • Inflammation was the pathway affected in the high dose group at all time points. • Ion homeostasis and muscle activity pathways were affected in the

“Retention Projection” Enables Reliable Use of Shared Gas Chromatographic Retention Data Across Labs, Instruments, and Methods

PubMed Central

Barnes, Brian B.; Wilson, Michael B.; Carr, Peter W.; Vitha, Mark F.; Broeckling, Corey D.; Heuberger, Adam L.; Prenni, Jessica; Janis, Gregory C.; Corcoran, Henry; Snow, Nicholas H.; Chopra, Shilpi; Dhandapani, Ramkumar; Tawfall, Amanda; Sumner, Lloyd W.; Boswell, Paul G.

2014-01-01

Gas chromatography-mass spectrometry (GC-MS) is a primary tool used to identify compounds in complex samples. Both mass spectra and GC retention times are matched to those of standards, but it is often impractical to have standards on hand for every compound of interest, so we must rely on shared databases of MS data and GC retention information. Unfortunately, retention databases (e.g. linear retention index libraries) are experimentally restrictive, notoriously unreliable, and strongly instrument dependent, relegating GC retention information to a minor, often negligible role in compound identification despite its potential power. A new methodology called “retention projection” has great potential to overcome the limitations of shared chromatographic databases. In this work, we tested the reliability of the methodology in five independent laboratories. We found that even when each lab ran nominally the same method, the methodology was 3-fold more accurate than retention indexing because it properly accounted for unintentional differences between the GC-MS systems. When the labs used different methods of their own choosing, retention projections were 4- to 165-fold more accurate. More importantly, the distribution of error in the retention projections was predictable across different methods and labs, thus enabling automatic calculation of retention time tolerance windows. Tolerance windows at 99% confidence were generally narrower than those widely used even when physical standards are on hand to measure their retention. With its high accuracy and reliability, the new retention projection methodology makes GC retention a reliable, precise tool for compound identification, even when standards are not available to the user. PMID:24205931

Acute Lung Injury Edema Fluid Decreases Net Fluid Transport across Human Alveolar Epithelial Type II Cells*

PubMed Central

Lee, Jae W.; Fang, Xiaohui; Dolganov, Gregory; Fremont, Richard D.; Bastarache, Julie A.; Ware, Lorraine B.; Matthay, Michael A.

2009-01-01

Most patients with acute lung injury (ALI) have reduced alveolar fluid clearance that has been associated with higher mortality. Several mechanisms may contribute to the decrease in alveolar fluid clearance. In this study, we tested the hypothesis that pulmonary edema fluid from patients with ALI might reduce the expression of ion transport genes responsible for vectorial fluid transport in primary cultures of human alveolar epithelial type II cells. Following exposure to ALI pulmonary edema fluid, the gene copy number for the major sodium and chloride transport genes decreased. By Western blot analyses, protein levels of αENaC, α1Na,K-ATPase, and cystic fibrosis transmembrane conductance regulator decreased as well. In contrast, the gene copy number for several inflammatory cytokines increased markedly. Functional studies demonstrated that net vectorial fluid transport was reduced for human alveolar type II cells exposed to ALI pulmonary edema fluid compared with plasma (0.02±0.05 versus 1.31±0.56 μl/cm2/h, p<0.02). An inhibitor of p38 MAPK phosphorylation (SB202190) partially reversed the effects of the edema fluid on net fluid transport as well as gene and protein expression of the main ion transporters. In summary, alveolar edema fluid from patients with ALI induced a significant reduction in sodium and chloride transport genes and proteins in human alveolar epithelial type II cells, effects that were associated with a decrease in net vectorial fluid transport across human alveolar type II cell monolayers. PMID:17580309

A viscoelastic deadly fluid in carnivorous pitcher plants.

PubMed

Gaume, Laurence; Forterre, Yoel

2007-11-21

The carnivorous plants of the genus Nepenthes, widely distributed in the Asian tropics, rely mostly on nutrients derived from arthropods trapped in their pitcher-shaped leaves and digested by their enzymatic fluid. The genus exhibits a great diversity of prey and pitcher forms and its mechanism of trapping has long intrigued scientists. The slippery inner surfaces of the pitchers, which can be waxy or highly wettable, have so far been considered as the key trapping devices. However, the occurrence of species lacking such epidermal specializations but still effective at trapping insects suggests the possible implication of other mechanisms. Using a combination of insect bioassays, high-speed video and rheological measurements, we show that the digestive fluid of Nepenthes rafflesiana is highly viscoelastic and that this physical property is crucial for the retention of insects in its traps. Trapping efficiency is shown to remain strong even when the fluid is highly diluted by water, as long as the elastic relaxation time of the fluid is higher than the typical time scale of insect movements. This finding challenges the common classification of Nepenthes pitchers as simple passive traps and is of great adaptive significance for these tropical plants, which are often submitted to high rainfalls and variations in fluid concentration. The viscoelastic trap constitutes a cryptic but potentially widespread adaptation of Nepenthes species and could be a homologous trait shared through common ancestry with the sundew (Drosera) flypaper plants. Such large production of a highly viscoelastic biopolymer fluid in permanent pools is nevertheless unique in the plant kingdom and suggests novel applications for pest control.

Fluid Dynamics of Magnetic Nanoparticles in Simulated Blood Vessels

NASA Astrophysics Data System (ADS)

Blue, Lauren; Sewell, Mary Kathryn; Brazel, Christopher S.

2008-11-01

Magnetic nanoparticles (MNPs) can be used to locally target therapies and offer the benefit of using an AC magnetic field to combine hyperthermia treatment with the triggered release of therapeutic agents. Here, we investigate localization of MNPs in a simulated environment to understand the relationship between magnetic field intensity and bulk fluid dynamics to determine MNP retention in a simulated blood vessel. As MNPs travel through blood vessels, they can be slowed or trapped in a specific area by applying a magnetic field. Magnetic cobalt ferrite nanoparticles were synthesized and labeled with a fluorescent rhodamine tag to visualize patterns in a flow cell, as monitored by a fluorescence microscope. Particle retention was determined as a function of flow rate, concentration, and magnetic field strength. Understanding the relationship between magnetic field intensity, flow behavior and nanoparticle characteristics will aid in the development of therapeutic systems specifically targeted to diseased tissue.

Evaluating the Impact of National Educational Policy to Reduce Retention and Increase Achievement in Compulsory Education

ERIC Educational Resources Information Center

Barata, M. Clara; Calheiros, M. Manuela; Patrício, Joana Nunes; Graça, João; Lima, M. Luisa

2015-01-01

Despite the accumulated evidence that retention is an ineffective and potentially harmful remedial strategy, several countries struggle with high levels of retention in compulsory schooling. This article provides evidence of the impact of the Portuguese national educational policy "Programa Mais Sucesso Escolar" (PMSE) using class size,…

Inductive Learning: Does Interleaving Exemplars Affect Long-Term Retention?

ERIC Educational Resources Information Center

Zulkiply, Norehan; Burt, Jennifer S.

2013-01-01

Purpose: The present study investigated whether or not the benefits of interleaving of exemplars from several categories vary with retention interval in inductive learning. Methodology: Two experiments were conducted using paintings (Experiment 1) and textual materials (Experiment 2), and the experiments used a mixed factorial design. Forty…

Unusual Severe Complication Following Transarterial Chemoembolization for Metastatic Malignant Melanoma: Giant Intrahepatic Cyst and Fatal Hepatic Failure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ataergin, Selmin, E-mail: sataergin@superonline.co; Tasar, Mustafa; Solchaga, Luis

2009-03-15

We describe a 45-year-old male patient with malignant melanoma who underwent hepatic arterial chemoembolization due to liver metastases. Four months after the procedure, the patient developed a giant cystic cavity in the liver. Cytologic examination of the cystic fluid retention revealed necrotic tumor material. The fluid was drained by percutaneous catheter, but the patient developed hepatic failure. This case represents another rare complication of transarterial chemoembolization and shows that transarterial chemoembolization may have rare fatal complications.

Body fluid volumes in rats with mestranol-induced hypertension

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fowler, W.L. Jr.; Johnson, J.A.; Kurz, K.D.

Because estrogens have been reported to produce sodium retention, this study investigated the possibility that hypertension in rats resulting from the ingestion of an estrogen used as an oral contraceptive could be due to increases in body fluid volumes. Female rats were given feed containing mestranol for 1, 3, and 6 mo; control rats were given the feed without mestranol. The mestranol-treated rats had higher arterial pressures than the controls only after 6 mo of treatment. Plasma volume, extracellular fluid volume, and total body water were measured in each rat by the distribution volumes of radioiodinated serum albumin, /sup 32/SO/submore » 4/, and tritiated water, respectively. The body fluid volumes, expressed per 100 g of body weight, were not different between the mestranol-treated rats and their controls at any of the three treatment times. Due to differences in body weight and lean body mass between the mestranol-treated and the control rats, these volumes also were expressed per 100 g of lean body mass. Again, no differences were observed between the mestranol-treated rats and the control rats for any of these body fluid compartments at any of the treatment times. These studies, therefore, were unable to provide evidence that increases in body fluid volumes contributed to the elevated arterial pressure in this rat model of oral contraceptive hypertension.« less

Cholesterol-dependent retention of GPI-anchored proteins in endosomes.

PubMed Central

Mayor, S; Sabharanjak, S; Maxfield, F R

1998-01-01

Several cell surface eukaryotic proteins have a glycosylphosphatidylinositol (GPI) modification at the Cterminal end that serves as their sole means of membrane anchoring. Using fluorescently labeled ligands and digital fluorescence microscopy, we show that contrary to the potocytosis model, GPI-anchored proteins are internalized into endosomes that contain markers for both receptor-mediated uptake (e.g. transferrin) and fluid phase endocytosis (e.g. dextrans). This was confirmed by immunogold electron microscopy and the observation that a fluorescent folate derivative bound to the GPI-anchored folate receptor is internalized into the same compartment as co-internalized horseradish peroxidase-transferrin; the folate fluorescence was quenched when cells subsequently were incubated with diaminobenzidine and H2O2. Most of the GPI-anchored proteins are recycled back to the plasma membrane but at a rate that is at least 3-fold slower than C6-NBD-sphingomyelin or recycling receptors. This endocytic retention is regulated by the level of cholesterol in cell membranes; GPI-anchored proteins are recycled back to the cell surface at the same rate as recycling transferrin receptors and C6-NBD-sphingomyelin in cholesterol-depleted cells. Cholesterol-dependent endocytic sorting of GPI-anchored proteins is consistent with the involvement of specialized lipid domains or 'rafts' in endocytic sorting. These results provide an alternative explanation for GPI-requiring functions of some GPI-anchored proteins. PMID:9707422

Transport and retention of bacteria and viruses in biochar-amended sand.

PubMed

Sasidharan, Salini; Torkzaban, Saeed; Bradford, Scott A; Kookana, Rai; Page, Declan; Cook, Peter G

2016-04-01

The transport and retention of Escherichia coli and bacteriophages (PRD1, MS2 and ФX174), as surrogates for human pathogenic bacteria and viruses, respectively, were studied in the sand that was amended with several types of biochar produced from various feedstocks. Batch and column studies were conducted to distinguish between the role of attachment and straining in microbe retention during transport. Batch experiments conducted at various solution chemistries showed negligible attachment of viruses and bacteria to biochar before or after chemical activation. At any given solution ionic strength, the attachment of viruses to sand was significantly higher than that of biochar, whereas bacteria showed no attachment to either sand or biochar. Consistent with batch results, biochar addition (10% w/w) to sand reduced virus retention in the column experiments, suggesting a potential negative impact of biochar application to soil on virus removal. In contrast, the retention of bacteria was enhanced in biochar-amended sand columns. However, elimination of the fine fraction (<60μm) of biochar particles in biochar-amended sand columns significantly reduced bacteria retention. Results from batch and column experiments suggest that land application of biochar may only play a role in microbe retention via straining, by alteration of pore size distribution, and not via attachment. Consequently, the particle size distribution of biochar and sediments is a more important factor than type of biochar in determining whether land application of biochar enhances or diminishes microbial retention. Copyright © 2016 Elsevier B.V. All rights reserved.

Fluid and electrolyte control in simulated and actual spaceflight

NASA Technical Reports Server (NTRS)

Leach, C. S.; Johnson, P. C., Jr.

1985-01-01

Effects of microgravity on body fluid distribution and electrolyte and hormonal levels of astronauts have been studied since the early manned space missions. Bedrested subjects have been used as controls to separate effects of microgravity from those of hypokinesia. These investigations have led to documentation of the physiological effects of spaceflight and to a unified theory of response to microgravity. During flight, crewmembers have decreased thirst and a net loss of body water, sodium, and potassium. These changes seem to be initiated by passive transfer of extracellular fluid resulting in increased central venous pressure (CVP), to which the homeostatic mechanisms respond. A new equilibrium state is maintained during flight; it does not change in response to negative calcium and nitrogen balances during flight. On reexposure to gravity, profound water and salt retention occurs to replete extracellular fluid. Attempts to avoid cardiac deconditioning by repleting water and salt before leaving microgravity have somewhat ameliorated postural hypotension but have had little effect on CVP, cardiac chamber size or electrolyte dynamics.

When sticky fluids don't stick: yield-stress fluid drops on heated surfaces

NASA Astrophysics Data System (ADS)

Blackwell, Brendan; Wu, Alex; Ewoldt, Randy

2016-11-01

Yield-stress fluids, including gels and pastes, are effectively fluid at high stress and solid at low stress. In liquid-solid impacts, these fluids can stick and accumulate where they impact; this sticky behavior motivates several applications of these rheologically-complex materials. Here we describe experiments with aqueous yield stress fluids that are more 'sticky' than water at room temperature (e.g. supporting larger coating thicknesses), but are less 'sticky' at higher temperatures. Specifically, we study the conditions for aqueous yield stress fluids to bounce and slide on heated surfaces when water sticks. Here we present high-speed imaging and color interferometry to observe the thickness of the vapor layer between the drop and the surface during both stick and non-stick events. We use these data to gain insight into the physics behind the phenomenon of the yield-stress fluids bouncing and sliding, rather than sticking, on hot surfaces.

Urinary retention and syndrome of inappropriate antidiuretic hormone secretion (SIADH) secondary to impacted gravid uterus.

PubMed

Irani, M; Fisher, N; Mor, A; Bensinger, G

2016-06-01

Urinary retention is an emergency that rarely occurs during pregnancy. Previous case reports have suggested multiple risk factors that can cause the gravid uterus to become impacted in the pelvis leading to lower bladder or urethral compression with subsequent urinary retention. However, no cases of urinary obstruction in a pregnancy that was complicated with severe electrolyte imbalance have been reported. To our knowledge, we report the first case of a 31-year-old woman presenting at 8 weeks' gestation with acute urinary retention caused by a retroflexed, retroverted uterus with a 6-cm posterior uterine fibroid leading to syndrome of inappropriate antidiuretic hormone secretion and severe hyponatremia requiring intensive care unit admission. The cornerstones of effective management of urinary retention should include: (i) urgent bladder catheterization; (ii) assessment of sodium levels to rule out syndrome of inappropriate antidiuretic hormone secretion, and prompt treatment before neurological damage occurs; (iii) reduction of the impacted uterus; and (iv) monitoring for post-obstructive diuresis. © 2016 Japan Society of Obstetrics and Gynecology.

Multiphase fluid characterization system

DOEpatents

Sinha, Dipen N.

2014-09-02

A measurement system and method for permitting multiple independent measurements of several physical parameters of multiphase fluids flowing through pipes are described. Multiple acoustic transducers are placed in acoustic communication with or attached to the outside surface of a section of existing spool (metal pipe), typically less than 3 feet in length, for noninvasive measurements. Sound speed, sound attenuation, fluid density, fluid flow, container wall resonance characteristics, and Doppler measurements for gas volume fraction may be measured simultaneously by the system. Temperature measurements are made using a temperature sensor for oil-cut correction.

Bryophyte species richness on retention aspens recovers in time but community structure does not.

PubMed

Oldén, Anna; Ovaskainen, Otso; Kotiaho, Janne S; Laaka-Lindberg, Sanna; Halme, Panu

2014-01-01

Green-tree retention is a forest management method in which some living trees are left on a logged area. The aim is to offer 'lifeboats' to support species immediately after logging and to provide microhabitats during and after forest re-establishment. Several studies have shown immediate decline in bryophyte diversity after retention logging and thus questioned the effectiveness of this method, but longer term studies are lacking. Here we studied the epiphytic bryophytes on European aspen (Populus tremula L.) retention trees along a 30-year chronosequence. We compared the bryophyte flora of 102 'retention aspens' on 14 differently aged retention sites with 102 'conservation aspens' on 14 differently aged conservation sites. We used a Bayesian community-level modelling approach to estimate the changes in bryophyte species richness, abundance (area covered) and community structure during 30 years after logging. Using the fitted model, we estimated that two years after logging both species richness and abundance of bryophytes declined, but during the following 20-30 years both recovered to the level of conservation aspens. However, logging-induced changes in bryophyte community structure did not fully recover over the same time period. Liverwort species showed some or low potential to benefit from lifeboating and high potential to re-colonise as time since logging increases. Most moss species responded similarly, but two cushion-forming mosses benefited from the logging disturbance while several weft- or mat-forming mosses declined and did not re-colonise in 20-30 years. We conclude that retention trees do not function as equally effective lifeboats for all bryophyte species but are successful in providing suitable habitats for many species in the long-term. To be most effective, retention cuts should be located adjacent to conservation sites, which may function as sources of re-colonisation and support the populations of species that require old-growth forests.

An evaluation and comparison of intraventricular, intraparenchymal, and fluid-coupled techniques for intracranial pressure monitoring in patients with severe traumatic brain injury.

PubMed

Vender, John; Waller, Jennifer; Dhandapani, Krishnan; McDonnell, Dennis

2011-08-01

Intracranial pressure measurements have become one of the mainstays of traumatic brain injury management. Various technologies exist to monitor intracranial pressure from a variety of locations. Transducers are usually placed to assess pressure in the brain parenchyma and the intra-ventricular fluid, which are the two most widely accepted compartmental monitoring sites. The individual reliability and inter-reliability of these devices with and without cerebrospinal fluid diversion is not clear. The predictive capability of monitors in both of these sites to local, regional, and global changes also needs further clarification. The technique of monitoring intraventricular pressure with a fluid-coupled transducer system is also reviewed. There has been little investigation into the relationship among pressure measurements obtained from these two sources using these three techniques. Eleven consecutive patients with severe, closed traumatic brain injury not requiring intracranial mass lesion evacuation were admitted into this prospective study. Each patient underwent placement of a parenchymal and intraventricular pressure monitor. The ventricular catheter tubing was also connected to a sensor for fluid-coupled measurement. Pressure from all three sources was measured hourly with and without ventricular drainage. Statistically significant correlation within each monitoring site was seen. No monitoring location was more predictive of global pressure changes or more responsive to pressure changes related to patient stimulation. However, the intraventricular pressure measurements were not reliable in the presence of cerebrospinal fluid drainage whereas the parenchymal measurements remained unaffected. Intraparenchymal pressure monitoring provides equivalent, statistically similar pressure measurements when compared to intraventricular monitors in all care and clinical settings. This is particularly valuable when uninterrupted cerebrospinal fluid drainage is desirable.

Recommendations for snag retention in southwestern mixed-conifer and ponderosa pine forests: History and current status

Treesearch

Joseph L. Ganey

2016-01-01

Snags provide habitat for numerous species of wildlife. Several authors have provided recommendations for snag retention in southwestern mixed-conifer and ponderosa pine (Pinus ponderosa) forests. Most recommendations were presented in terms of minimum snag density and/or size. I summarized the history of recommendations for snag retention in these forest...

Urinary Retention Associated with Stroke.

PubMed

Umemura, Takeru; Ohta, Hirotsugu; Yokota, Akira; Yarimizu, Shiroh; Nishizawa, Shigeru

Patients often exhibit urinary retention following a stroke. Various neuropathological and animal studies have implicated the medulla oblongata, pons, limbic system, frontal lobe as areas responsible for micturition control, although the exact area responsible for urinary retention after stroke is not clear. The purpose of this study was to identify the stroke area responsible for urinary retention by localizing the areas where strokes occur. We assessed 110 patients with cerebral infarction and 27 patients with cerebral hemorrhage (78 men, 59 women; mean age, 73.0 years) who had been admitted to our hospital between October, 2012 and September, 2013. We used computed tomography (CT) and magnetic resonance imaging (MRI) to investigate the stroke location, and evaluated whether post-stroke urinary retention occurred. Twelve (8.8%) of the 137 patients (7 men, 5 women; mean age, 78.8 years) exhibited urinary retention after a stroke. Stroke occurred in the right/left dominant hemisphere in 7 patients; nondominant hemisphere in 1; cerebellum in 3; and brainstem in 1. Strokes in the dominant hemisphere were associated with urinary retention (P = 0.0314), particularly in the area of the insula (P < 0.01). We concluded that stroke affecting the insula of the dominant hemisphere tends to cause urinary retention.

Mobile Learning and Student Retention

ERIC Educational Resources Information Center

Fozdar, Bharat Inder; Kumar, Lalita S.

2007-01-01

Student retention in open and distance learning (ODL) is comparatively poor to traditional education and, in some contexts, embarrassingly low. Literature on the subject of student retention in ODL indicates that even when interventions are designed and undertaken to improve student retention, they tend to fall short. Moreover, this area has not…

Advancing the science of recruitment and retention of ethnically diverse populations.

PubMed

Nápoles, Anna M; Chadiha, Letha A

2011-06-01

We highlight several critical challenges that must be addressed to accelerate the advancement of the science on recruitment and retention of ethnically diverse older adults into health research. These include the relative lack of attention by researchers to methodological issues related to recruitment and retention of ethnically diverse populations and the inadequacy of funding to advance systematically this field. We describe strategies used by the Resource Centers on Minority Aging Research and other National Institute of Aging-funded programs to advance the science of recruitment of ethnically diverse older adults. Finally, we propose a set of broad recommendations designed to generate a body of evidence on successful methods of recruitment and retention of ethnically diverse populations in health research. To eliminate health disparities and better understand aging processes in ethnically diverse populations, much more research is needed on effective strategies for increasing minority enrollment in health research. Comparative effectiveness research on more intensive recruitment and retention methods, which are often needed for including diverse populations, will require dedicated funding and concerted efforts by investigators.

Natural resolution or intervention for fluid collections in acute severe pancreatitis.

PubMed

Sarathi Patra, P; Das, K; Bhattacharyya, A; Ray, S; Hembram, J; Sanyal, S; Dhali, G K

2014-12-01

Revisions in terminology of fluid collections in acute pancreatitis have necessitated reanalysis of their evolution and outcome. The course of fluid collections in patients with acute pancreatitis was evaluated prospectively. Consecutive adults with acute pancreatitis, who had contrast-enhanced CT (CECT) within 5-7 days of symptom onset, were enrolled in a prospective cohort study in a tertiary-care centre. Patients were treated according to standard guidelines. Follow-up transabdominal ultrasonography was done at 4-week intervals for at least 6 months. CECT was repeated at 6-10 weeks, or at any time if there were new or persistent symptoms. Asymptomatic collections were followed until spontaneous resolution. Risk factors for pancreatic pseudocysts or walled-off necrosis (WON) were assessed in multivariable analyses. Of 122 patients with acute pancreatitis, 109 were analysed. Some 91 patients (83·5 per cent) had fluid collections at baseline. Eleven of 29 with interstitial oedematous pancreatitis had acute peripancreatic fluid collections, none of which evolved into pseudocysts. All 80 patients with acute necrotizing pancreatitis had at least one acute necrotizing collection (ANC); of these, five patients died (2 after drainage), three underwent successful drainage within 5 weeks, and collections resolved spontaneously in 33 and evolved into WON in 39. By 6 months' follow-up, WON had required drainage in eight patients, resolved spontaneously in 23 and was persistent but asymptomatic in seven. Factors associated with increased risk of WON were blood urea nitrogen 20 mg/dl or more (odds ratio (OR) 10·96, 95 per cent c.i. 2·57 to 46·73; P = 0·001) and baseline ANC diameter greater than 6 cm (OR 14·57, 1·60 to 132·35; P = 0·017). Baseline ANC diameter over 6 cm was the only independent predictor of either the need for drainage or persistence of such collections beyond 6 months (hazard ratio 6·61, 1·77 to 24·59; P = 0·005

Competing retention pathways of uranium upon reaction with Fe(II)

NASA Astrophysics Data System (ADS)

Massey, Michael S.; Lezama-Pacheco, Juan S.; Jones, Morris E.; Ilton, Eugene S.; Cerrato, José M.; Bargar, John R.; Fendorf, Scott

2014-10-01

Biogeochemical retention processes, including adsorption, reductive precipitation, and incorporation into host minerals, are important in contaminant transport, remediation, and geologic deposition of uranium. Recent work has shown that U can become incorporated into iron (hydr)oxide minerals, with a key pathway arising from Fe(II)-induced transformation of ferrihydrite, (Fe(OH)3·nH2O) to goethite (α-FeO(OH)); this is a possible U retention mechanism in soils and sediments. Several key questions, however, remain unanswered regarding U incorporation into iron (hydr)oxides and this pathway's contribution to U retention, including: (i) the competitiveness of U incorporation versus reduction to U(IV) and subsequent precipitation of UO2; (ii) the oxidation state of incorporated U; (iii) the effects of uranyl aqueous speciation on U incorporation; and, (iv) the mechanism of U incorporation. Here we use a series of batch reactions conducted at pH ∼7, [U(VI)] from 1 to 170 μM, [Fe(II)] from 0 to 3 mM, and [Ca] at 0 or 4 mM coupled with spectroscopic examination of reaction products of Fe(II)-induced ferrihydrite transformation to address these outstanding questions. Uranium retention pathways were identified and quantified using extended X-ray absorption fine structure (EXAFS) spectroscopy, X-ray powder diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy. Analysis of EXAFS spectra showed that 14-89% of total U was incorporated into goethite, upon reaction with Fe(II) and ferrihydrite. Uranium incorporation was a particularly dominant retention pathway at U concentrations ⩽50 μM when either uranyl-carbonato or calcium-uranyl-carbonato complexes were dominant, accounting for 64-89% of total U. With increasing U(VI) and Fe(II) concentrations, U(VI) reduction to U(IV) became more prevalent, but U incorporation remained a functioning retention pathway. These findings highlight the potential importance of U(V) incorporation within iron

5 CFR 536.301 - Mandatory pay retention.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Mandatory pay retention. 536.301 Section... PAY RETENTION Pay Retention § 536.301 Mandatory pay retention. (a) Subject to the requirements in § 536.102 and this section, an agency must provide pay retention to an employee who moves between...

Prenatal diagnosis of Bartter syndrome: amniotic fluid aldosterone.

PubMed

Rachid, Myriam; Dreux, Sophie; Pean de Ponfilly, Gauthier; Vargas-Poussou, Rosa; Czerkiewicz, Isabelle; Chevenne, Didier; Oury, Jean-François; Deschênes, Georges; Muller, Françoise

2017-04-01

Bartter syndrome is a severe inherited tubulopathy characterized at birth by salt wasting, severe polyuria, dehydration, growth retardation and secondary hyperaldosteronism. Prenatally, the disease is usually discovered following onset of severe polyhydramnios. We studied amniotic fluid aldosterone concentration in cases of Bartter syndrome and in control groups. Amniotic fluid aldosterone was assayed by radioimmunoassay. We undertook a retrospective case-control study based on 36 cases of postnatally diagnosed Bartter syndrome and 144 controls matched for gestational age. Two controls groups were defined: controls with polyhydramnios (n=72) and control without polyhydramnios (n=72). Amniotic fluid aldosterone was compared between the three groups. The median amniotic fluid aldosterone concentration in the Bartter syndrome group (90 pg/mL) did not differ significantly from that in the controls with polyhydramnios (90 pg/mL, p=0.33) or the controls without polyhydramnios (87 pg/mL, p=0.41). In conclusion, amniotic fluid aldosterone assay cannot be used for prenatal diagnosis of Bartter syndrome.

Recruitment and Retention of Minority Students Entering Teacher Education.

ERIC Educational Resources Information Center

George, Thomas W.

There has been a severe decline in minority students entering preservice teacher education programs at the University of Tennessee, Knoxville, during the current decade. This paper outlines the recruiting and retention strategies directed toward high school students by the university to encourage them to choose teaching as a career. (JD)

Teacher Retention: Problems and Solutions

ERIC Educational Resources Information Center

McLaurin, Sidney E.; Smith, Willis; Smillie, Amanda

2009-01-01

There is a teacher retention crisis in the United States. The purpose of this paper is to answer the following questions: What contributes to teachers leaving the field? How has "No Child Left Behind" affected teacher retention? What can be done to retain good teachers? What impact do school administrators have on teacher retention?…

300 Area Building Retention Evaluation Mitigation Plan

DOE Office of Scientific and Technical Information (OSTI.GOV)

D. J. McBride

2007-07-03

Evaluate the long-term retention of several facilities associated with the PNNL Capability Replacement Laboratory and other Hanfor mission needs. WCH prepared a mitigation plan for three scenarios with different release dates for specific buildings. The evaluations present a proposed plan for providing utility services to retained facilities in support of a long-term (+20 year) lifespan in addition to temporary services to buildings with specified delayed release dates.

Preheating temperature effect on tritium retention in VPS-W

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sato, M.; Uchimura, H.; Toda, K.

The W coating by Vacuum Plasma Spraying (VPS) technology is thought to be reasonable for most plasma facing components in future fusion reactors. In this paper the deuterium retention behavior for the Vacuum Plasma Spraying (VPS) tungsten (W) coating has been studied to demonstrate the tritium retention as a function of heating temperature. It has been found that two major deuterium desorption stages were observed at the temperature regions of 400 - 700 K (Stage 1) and 900 - 1100 K (Stage 2), considering that Stage 1 has been linked to the desorption of deuterium trapped by near surface andmore » intrinsic defects, and Stage 2 has been related to the desorption of deuterium bound to impurities as C-D bonds. By heating the sample above 673 K, the major peak of C-1s shifted from C-O bond to C-C bond, where the retention of deuterium as Stage 2 has increased. Therefore it indicates that the hydrogen isotope retention was controlled by the amount of C-C bond in VPS, most of which was contaminated during the VPS coating process. The comparison of several samples (VPS-W with shading, VPS-W without shading and Polycrystalline W (PCW)) shows that the carbon impurity has a large affinity with deuterium and makes stable trapping states compared to that with intrinsic defects and grain boundaries. However, most of them was reduced by heating at 1173 K. Therefore, heating treatment is quite important to get rid of carbon impurities and refrain higher tritium retention in VPS. (authors)« less

Does skill retention benefit from retentivity and symbolic rehearsal? - two studies with a simulated process control task.

PubMed

Kluge, Annette; Frank, Barbara; Maafi, Sanaz; Kuzmanovska, Aleksandra

2016-05-01

Two experiments were designed to compare two symbolic rehearsal refresher interventions (imaginary practice, a hidden introspective process) and investigate the role of retentivity in skill retention. Retentivity is investigated as the ability to memorise and reproduce information and associations that were learned a short time ago. Both experiments comprised initial training (week 1), a symbolic rehearsal for the experimental group (week 2) and a retention assessment (week 3). In the first study, the experimental group received a symbolic rehearsal, while the control group received no rehearsal. In the second study, the experimental group received the same symbolic rehearsal used in study 1, enhanced with rehearsal tasks addressing human-computer interaction. The results showed that both symbolic rehearsal interventions were equally likely to mitigate skill decay. The retentivity showed medium to high correlations with skill retention in both studies, and the results suggest that subjects high in retentivity benefit more from a symbolic rehearsal refresher intervention. Practitioner Summary: Skill decay becomes a problem in situations in which jobs require the correct mastery of non-routine situations. Two experimental studies with simulated process control tasks showed that symbolic rehearsal and retentivity can significantly mitigate skill decay and that subjects higher in retentivity benefit more from refresher interventions.

Wildfire impacts on soil-water retention in the Colorado Front Range, United States

NASA Astrophysics Data System (ADS)

Ebel, Brian A.

2012-12-01

This work examined the plot-scale differences in soil-water retention caused by wildfire in the area of the 2010 Fourmile Canyon Fire in the Colorado Front Range, United States. We measured soil-water retention curves on intact cores and repacked samples, soil particle-size distributions, and organic matter content. Estimates were also made of plant-available water based on the soil-water retention curves. Parameters for use in soil-hydraulic property models were estimated; these parameters can be used in unsaturated flow modeling for comparing burned and unburned watersheds. The primary driver for measured differences in soil-water retention in burned and unburned soils was organic matter content and not soil-particle size distribution. The tendency for unburned south-facing soils to have greater organic matter content than unburned north-facing soils in this field area may explain why unburned south-facing soils had greater soil-water retention than unburned north-facing soils. Our results suggest that high-severity wildfire can "homogenize" soil-water retention across the landscape by erasing soil-water retention differences resulting from organic matter content, which for this site may be affected by slope aspect. This homogenization could have important implications for ecohydrology and plant succession/recovery in burned areas, which could be a factor in dictating the window of vulnerability of the landscape to flash floods and erosion that are a common consequence of wildfire.

Nursing Student Retention in Associate Degree Nursing Programs Utilizing a Retention Specialist

ERIC Educational Resources Information Center

Schrum, Ronna A.

2014-01-01

The purpose of this study was to examine specific variables associated with nursing student retention in Associate Degree Nursing (ADN) Programs. Jeffreys (2004) Nursing Undergraduate Retention and Success (NURS) conceptual model provided the framework for this descriptive correlational study. One hundred sixty eight pre-licensure associate degree…

Quantitative structure-retention relationships for gas chromatographic retention indices of alkylbenzenes with molecular graph descriptors.

PubMed

Ivanciuc, O; Ivanciuc, T; Klein, D J; Seitz, W A; Balaban, A T

2001-02-01

Quantitative structure-retention relationships (QSRR) represent statistical models that quantify the connection between the molecular structure and the chromatographic retention indices of organic compounds, allowing the prediction of retention indices of novel, not yet synthesized compounds, solely from their structural descriptors. Using multiple linear regression, QSRR models for the gas chromatographic Kováts retention indices of 129 alkylbenzenes are generated using molecular graph descriptors. The correlational ability of structural descriptors computed from 10 molecular matrices is investigated, showing that the novel reciprocal matrices give numerical indices with improved correlational ability. A QSRR equation with 5 graph descriptors gives the best calibration and prediction results, demonstrating the usefulness of the molecular graph descriptors in modeling chromatographic retention parameters. The sequential orthogonalization of descriptors suggests simpler QSRR models by eliminating redundant structural information.

A Viscoelastic Deadly Fluid in Carnivorous Pitcher Plants

PubMed Central

Gaume, Laurence; Forterre, Yoel

2007-01-01

Background The carnivorous plants of the genus Nepenthes, widely distributed in the Asian tropics, rely mostly on nutrients derived from arthropods trapped in their pitcher-shaped leaves and digested by their enzymatic fluid. The genus exhibits a great diversity of prey and pitcher forms and its mechanism of trapping has long intrigued scientists. The slippery inner surfaces of the pitchers, which can be waxy or highly wettable, have so far been considered as the key trapping devices. However, the occurrence of species lacking such epidermal specializations but still effective at trapping insects suggests the possible implication of other mechanisms. Methodology/Principal Findings Using a combination of insect bioassays, high-speed video and rheological measurements, we show that the digestive fluid of Nepenthes rafflesiana is highly viscoelastic and that this physical property is crucial for the retention of insects in its traps. Trapping efficiency is shown to remain strong even when the fluid is highly diluted by water, as long as the elastic relaxation time of the fluid is higher than the typical time scale of insect movements. Conclusions/Significance This finding challenges the common classification of Nepenthes pitchers as simple passive traps and is of great adaptive significance for these tropical plants, which are often submitted to high rainfalls and variations in fluid concentration. The viscoelastic trap constitutes a cryptic but potentially widespread adaptation of Nepenthes species and could be a homologous trait shared through common ancestry with the sundew (Drosera) flypaper plants. Such large production of a highly viscoelastic biopolymer fluid in permanent pools is nevertheless unique in the plant kingdom and suggests novel applications for pest control. PMID:18030325

Cerebrospinal fluid D-serine concentrations in major depressive disorder negatively correlate with depression severity.

PubMed

Ishiwata, Sayuri; Hattori, Kotaro; Sasayama, Daimei; Teraishi, Toshiya; Miyakawa, Tomoko; Yokota, Yuuki; Matsumura, Ryo; Nishikawa, Toru; Kunugi, Hiroshi

2018-01-15

D-serine is an endogenous co-agonist of N-methyl-D-aspartate receptor (NMDAR) and plays an important role in glutamate neurotransmission. Several studies suggested the possible involvement of D-serine related in the pathophysiology of psychiatric disorders including major depression disorders (MDD). We tried to examine whether cerebrospinal fluid (CSF) or plasma D-serine concentrations are altered in MDD and whether D-serine concentrations correlated with disease severity. 26 MDD patients and 27 healthy controls matched for age, sex and ethnicity were enrolled. We measured amino acids in these samples using by high-performance liquid chromatography with fluorometric detection. D-serine and L-serine, precursor of D-serine, levels in CSF or plasma were not significantly different in patients of MDD compared to controls. Furthermore, a significant correlation between D-serine levels in CSF and Hamilton Depression Rating Scale (HAMD)-17 score was observed (r = -0.65, p = 0.006). Furthermore, we found a positive correlation between CSF D-serine and HVA concentrations in MDD patients (r = 0.54, p = 0.007). CSF D-serine concentrations were correlated with those of plasma in MDD (r = 0.61, p = 0.01) but not in controls. In CSF, we also confirmed a significant correlation between D-serine and L-serine levels in MDD (r = 0.72, p < 0.0001) and controls (r = 0.70, p < 0.0001). The study has some limitations; sample size was relatively small and most patients were medicated. We revealed that CSF D-serine concentrations were correlated with depression severity and HVA concentrations and further investigation were required to reveal the effect of medication and disease heterogeneity. Copyright © 2017 Elsevier B.V. All rights reserved.

Job embeddedness and nurse retention.

PubMed

Reitz, O Ed; Anderson, Mary Ann; Hill, Pamela D

2010-01-01

Nurse retention is a different way of conceptualizing the employer-employee relationship when compared with turnover. Job embeddedness (JE), a construct based on retention, represents the sum of reasons why employees remain at their jobs. However, JE has not been investigated in relation to locale (urban or rural) or exclusively with a sample of registered nurses (RNs). The purpose of this study was to determine what factors (JE, age, gender, locale, and income) help predict nurse retention. A cross-sectional mailed survey design was used with RNs in different locales (urban or rural). Job embeddedness was measured by the score on the composite, standardized instrument. Nurse retention was measured by self-report items concerning intent to stay. A response rate of 49.3% was obtained. The typical respondent was female (96.1%), white, non-Hispanic (87.4%), and married (74.9%). Age and JE were predictive of nurse retention and accounted for 26% of the explained variance in intent to stay. Although age was a significant predictor of intent to stay, it accounted for only 1.4% of the variance while JE accounted for 24.6% of the variance of nurse retention (as measured by intent to stay). Older, more "embedded" nurses are more likely to remain employed in their current organization. Based on these findings, JE may form the basis for the development of an effective nurse retention program.

Calculation of Retention Time Tolerance Windows with Absolute Confidence from Shared Liquid Chromatographic Retention Data

PubMed Central

Boswell, Paul G.; Abate-Pella, Daniel; Hewitt, Joshua T.

2015-01-01

Compound identification by liquid chromatography-mass spectrometry (LC-MS) is a tedious process, mainly because authentic standards must be run on a user’s system to be able to confidently reject a potential identity from its retention time and mass spectral properties. Instead, it would be preferable to use shared retention time/index data to narrow down the identity, but shared data cannot be used to reject candidates with an absolute level of confidence because the data are strongly affected by differences between HPLC systems and experimental conditions. However, a technique called “retention projection” was recently shown to account for many of the differences. In this manuscript, we discuss an approach to calculate appropriate retention time tolerance windows for projected retention times, potentially making it possible to exclude candidates with an absolute level of confidence, without needing to have authentic standards of each candidate on hand. In a range of multi-segment gradients and flow rates run among seven different labs, the new approach calculated tolerance windows that were significantly more appropriate for each retention projection than global tolerance windows calculated for retention projections or linear retention indices. Though there were still some small differences between the labs that evidently were not taken into account, the calculated tolerance windows only needed to be relaxed by 50% to make them appropriate for all labs. Even then, 42% of the tolerance windows calculated in this study without standards were narrower than those required by WADA for positive identification, where standards must be run contemporaneously. PMID:26292624

Calculation of retention time tolerance windows with absolute confidence from shared liquid chromatographic retention data.

PubMed

Boswell, Paul G; Abate-Pella, Daniel; Hewitt, Joshua T

2015-09-18

Compound identification by liquid chromatography-mass spectrometry (LC-MS) is a tedious process, mainly because authentic standards must be run on a user's system to be able to confidently reject a potential identity from its retention time and mass spectral properties. Instead, it would be preferable to use shared retention time/index data to narrow down the identity, but shared data cannot be used to reject candidates with an absolute level of confidence because the data are strongly affected by differences between HPLC systems and experimental conditions. However, a technique called "retention projection" was recently shown to account for many of the differences. In this manuscript, we discuss an approach to calculate appropriate retention time tolerance windows for projected retention times, potentially making it possible to exclude candidates with an absolute level of confidence, without needing to have authentic standards of each candidate on hand. In a range of multi-segment gradients and flow rates run among seven different labs, the new approach calculated tolerance windows that were significantly more appropriate for each retention projection than global tolerance windows calculated for retention projections or linear retention indices. Though there were still some small differences between the labs that evidently were not taken into account, the calculated tolerance windows only needed to be relaxed by 50% to make them appropriate for all labs. Even then, 42% of the tolerance windows calculated in this study without standards were narrower than those required by WADA for positive identification, where standards must be run contemporaneously. Copyright © 2015 Elsevier B.V. All rights reserved.

Retention behavior of lipids in reversed-phase ultrahigh-performance liquid chromatography-electrospray ionization mass spectrometry.

PubMed

Ovčačíková, Magdaléna; Lísa, Miroslav; Cífková, Eva; Holčapek, Michal

2016-06-10

Reversed-phase ultrahigh-performance liquid chromatography (RP-UHPLC) method using two 15cm sub-2μm particles octadecylsilica gel columns is developed with the goal to separate and unambiguously identify a large number of lipid species in biological samples. The identification is performed by the coupling with high-resolution tandem mass spectrometry (MS/MS) using quadrupole - time-of-flight (QTOF) instrument. Electrospray ionization (ESI) full scan and tandem mass spectra are measured in both polarity modes with the mass accuracy better than 5ppm, which provides a high confidence of lipid identification. Over 400 lipid species covering 14 polar and nonpolar lipid classes from 5 lipid categories are identified in total lipid extracts of human plasma, human urine and porcine brain. The general dependences of relative retention times on relative carbon number or relative double bond number are constructed and fit with the second degree polynomial regression. The regular retention patterns in homologous lipid series provide additional identification point for UHPLC/MS lipidomic analysis, which increases the confidence of lipid identification. The reprocessing of previously published data by our and other groups measured in the RP mode and ultrahigh-performance supercritical fluid chromatography on the silica column shows more generic applicability of the polynomial regression for the description of retention behavior and the prediction of retention times. The novelty of this work is the characterization of general trends in the retention behavior of lipids within logical series with constant fatty acyl length or double bond number, which may be used as an additional criterion to increase the confidence of lipid identification. Copyright © 2016 Elsevier B.V. All rights reserved.

Physician recruitment and retention in rural and underserved areas.

PubMed

Lee, Dane M; Nichols, Tommy

2014-01-01

The purpose of this paper is to identify the challenges when recruiting and retaining rural physicians and to ascertain methods that make rural physician recruitment and retention successful. There are studies that suggest rural roots is an important factor in recruiting rural physicians, while others look at rural health exposure in medical school curricula, self-actualization, community sense and spousal perspectives in the decision to practice rural medicine. An extensive literature review was performed using Academic Search Complete, PubMed and The Cochrane Collaboration. Key words were rural, rural health, community hospital(s), healthcare, physicians, recruitment, recruiting, retention, retaining, physician(s) and primary care physician(s). Inclusion criteria were peer-reviewed full-text articles written in English, published from 1997 and those limited to USA and Canada. Articles from foreign countries were excluded owing to their unique healthcare systems. While there are numerous articles that call for special measures to recruit and retain physicians in rural areas, there is an overall dearth. This review identifies several articles that suggest recruitment and retention techniques. There is a need for a research agenda that includes valid, reliable and rigorous analysis regarding formulating and implementing these strategies. Rural Americans are under-represented when it comes to healthcare and what research there is to assist recruitment and retention is difficult to find. This paper identify the relevant research and highlights key strategies.

Prenatal diagnosis of Bartter syndrome: amniotic fluid aldosterone.

PubMed

Rachid, Myriam L; Dreux, Sophie; Pean de Ponfilly, Gauthier; Vargas-Poussou, Rosa; Czerkiewicz, Isabelle; Chevenne, Didier; Oury, Jean-François; Deschênes, Georges; Muller, Françoise

2016-01-01

Bartter syndrome is a severe inherited tubulopathy characterized by postnatal salt wasting, severe polyuria, dehydration, failure to thrive and secondary hyperaldosteronism. Prenatally, the disease is usually discovered following the onset of severe polyhydramnios in the second trimester. We studied amniotic fluid aldosterone concentration in Bartter syndrome and in controls. Amniotic fluid aldosterone was assayed by radioimmunoassay. We undertook a retrospective case-control study based on 36 cases of prenatally suspected and postnatally confirmed Bartter syndrome (22 with identified mutations): and 72 gestational age matched controls presenting with polyhydramnios and 72 without polyhydramnios. Amniotic fluid aldosterone was compared between the three groups. The median amniotic fluid aldosterone concentration in the Bartter syndrome group (90 pg/mL) was not different from that in the controls with polyhydramnios (90 pg/mL, P = 0.33) or without polyhydramnios (87 pg/mL, P = 0.41). Amniotic fluid aldosterone assay cannot be used for prenatal diagnosis of Bartter syndrome. © 2015 John Wiley & Sons, Ltd. © 2015 John Wiley & Sons, Ltd.

[Arterial pressure curve and fluid status].

PubMed

Pestel, G; Fukui, K

2009-04-01

Fluid optimization is a major contributor to improved outcome in patients. Unfortunately, anesthesiologists are often in doubt whether an additional fluid bolus will improve the hemodynamics of the patient or not as excess fluid may even jeopardize the condition. This article discusses physiological concepts of liberal versus restrictive fluid management followed by a discussion on the respective capabilities of various monitors to predict fluid responsiveness. The parameter difference in pulse pressure (dPP), derived from heart-lung interaction in mechanically ventilated patients is discussed in detail. The dPP cutoff value of 13% to predict fluid responsiveness is presented together with several assessment techniques of dPP. Finally, confounding variables on dPP measurements, such as ventilation parameters, pneumoperitoneum and use of norepinephrine are also mentioned.

Wildfire impacts on soil-water retention in the Colorado Front Range, United States

USGS Publications Warehouse

Ebel, Brian A.

2012-01-01

This work examined the plot-scale differences in soil-water retention caused by wildfire in the area of the 2010 Fourmile Canyon Fire in the Colorado Front Range, United States. We measured soil-water retention curves on intact cores and repacked samples, soil particle-size distributions, and organic matter content. Estimates were also made of plant-available water based on the soil-water retention curves. Parameters for use in soil-hydraulic property models were estimated; these parameters can be used in unsaturated flow modeling for comparing burned and unburned watersheds. The primary driver for measured differences in soil-water retention in burned and unburned soils was organic matter content and not soil-particle size distribution. The tendency for unburned south-facing soils to have greater organic matter content than unburned north-facing soils in this field area may explain why unburned south-facing soils had greater soil-water retention than unburned north-facing soils. Our results suggest that high-severity wildfire can “homogenize” soil-water retention across the landscape by erasing soil-water retention differences resulting from organic matter content, which for this site may be affected by slope aspect. This homogenization could have important implications for ecohydrology and plant succession/recovery in burned areas, which could be a factor in dictating the window of vulnerability of the landscape to flash floods and erosion that are a common consequence of wildfire.

Effects of Constant Flow vs. Constant Pressure Perfusion on Fluid Filtration in Severe Hypothermic Isolated Blood-Perfused Rat Lungs.

PubMed

Halsøy, Kathrine; Kondratiev, Timofey; Tveita, Torkjel; Bjertnaes, Lars J

2016-01-01

Victims of severe accidental hypothermia are prone to fluid extravasation but rarely develop lung edema. We hypothesize that combined hypothermia-induced increase in pulmonary vascular resistance (PVR) and a concomitant fall in cardiac output protect the lungs against edema development. Our aim was to explore in hypothermic-isolated blood-perfused rat lungs whether perfusion at constant pressure influences fluid filtration differently from perfusion at constant flow. Isolated blood-perfused rat lungs were hanging freely in a weight transducer for measuring weight changes (ΔW). Fluid filtration coefficient (Kfc), was determined by transiently elevating left atrial pressure (Pla) by 5.8 mmHg two times each during normothermia (37°C) and during hypothermia (15°C). The lung preparations were randomized to two groups. One group was perfused with constant flow (Constant flow group) and the other group with constant pulmonary artery pressure (Constant PPA group). Microvascular pressure (Pmv) was determined before and during elevation of Pla (ΔPmv) by means of the double occlusion technique. Kfc was calculated with the formula Kfc = ΔW/ΔPmv/min. All Kfc values were normalized to predicted lung weight (P LW ), which was based on body weight (BW) according to the formula: P LW  = 0.0053 BW - 0.48 and presented as Kfc PLW in mg/min/mmHg/g. At cessation, bronchoalveolar lavage (BAL) fluid/perfusate protein concentration (B/P) ratio was determined photometrically. Data were analyzed with parametric or non-parametric tests as appropriate. p  < 0.05 considered as significant. Perfusate flow remained constant in the Constant flow group, but was more than halved during hypothermia in the Constant PPA group concomitant with a more fold increase in PVR. In the Constant flow group, Kfc PLW and B/P ratio increased significantly by more than 10-fold during hypothermia concerted by visible signs of edema in the trachea. Hemoglobin and hematocrit increased within

Poor ultrafiltration during nighttime dialysis in CAPD patients and its effects on fluid balance.

PubMed

Pagé, D E; Levine, D Z

1993-01-01

To evaluate fluid retention during the long nighttime peritoneal dwell in continuous ambulatory peritoneal dialysis (CAPD) patients, we measured remaining volumes in 70 patients. In only 50% of these patients were more than 2 L of fluid recovered; in 30% between 1.5 and 2 L were recovered; and in 17% of patients we retrieved less than 1.5 L of peritoneal fluid. In 3 of these patients, who were edematous and had marked pitting edema, we shortened the nighttime dwell by having the patients awaken after 4 hours and drain the dwell. This resulted in 3-5 kg of weight loss in each patient, when compared with each patient's previous use of long nighttime dwells. Finally, we propose in this report two automated methods whereby the period of nighttime dialysis can be controlled, while patients sleep, using a system of timer clamps.

Three-dimensional fluid-structure interaction case study on cubical fluid cavity with flexible bottom

NASA Astrophysics Data System (ADS)

Ghelardi, Stefano; Rizzo, Cesare; Villa, Diego

2017-12-01

In this paper, we report our study on a numerical fluid-structure interaction problem originally presented by Mok et al. (2001) in two dimensions and later studied in three dimensions by Valdés Vazquez (2007), Lombardi (2012), and Trimarchi (2012). We focus on a 3D test case in which we evaluated the sensitivity of several input parameters on the fluid and structural results. In particular, this analysis provides a starting point from which we can look deeper into specific aspects of these simulations and analyze more realistic cases, e.g., in sails design. In this study, using the commercial software ADINA™, we addressed a well-known unsteadiness problem comprising a square box representing the fluid domain with a flexible bottom modeled with structural shell elements. We compared data from previously published work whose authors used the same numerical approach, i.e., a partitioned approach coupling a finite volume solver (for the fluid domain) and a finite element solver (for the solid domain). Specifically, we established several benchmarks and made comparisons with respect to fluid and solid meshes, structural element types, and structural damping, as well as solution algorithms. Moreover, we compared our method with a monolithic finite element solution method. Our comparisons of new and old results provide an outline of best practices for such simulations.

A Scholarship Model for Student Recruitment and Retention in STEM Disciplines

ERIC Educational Resources Information Center

Yelamarthi, Kumar; Mawasha, P. Ruby

2010-01-01

A scholarship program offers enrichment, support, higher recruitment and retention, improved professional development towards employment, and increased graduate opportunities for underrepresented groups. In this paper, it is postulated that the development of a successful and competitive scholarship program is dependent on several variables…

The Evolutionary Economics of Embryonic-Sac Fluids in Squamate Reptiles.

PubMed

Bonnet, Xavier; Naulleau, Guy; Shine, Richard

2017-03-01

The parchment-shelled eggs of squamate reptiles take up substantial water from the nest environment, enabling the conversion of yolk into neonatal tissue and buffering the embryo against the possibility of subsequent dry weather. During development, increasing amounts of water are stored in the embryonic sacs (i.e., membranes around the embryo: amnion, allantois, and chorion). The evolution of viviparity (prolonged uterine retention of developing embryos) means that embryonic-sac fluid storage now imposes a cost (increased maternal burdening), confers less benefit (because the mother buffers fetal water balance), and introduces a potential conflict among uterine siblings (for access to finite water supplies). Our data on nine species of squamate reptiles and published information on three species show that the embryonic-sac fluids comprise around 33% of neonatal mass in viviparous species versus 94% in full-term eggs of oviparous squamates. Data on parturition in 149 vipers (Vipera aspis, a viviparous species) show that larger offspring store more fluids in their fetal sacs and that an increase in litter size is associated with a decrease in fluid-sac mass per offspring. Overall, the evolutionary transition from oviparity to viviparity may have substantially altered selective forces on offspring packaging and created competition among offspring for access to water reserves during embryonic development.

Subarachnoid Hemorrhage Severely Impairs Brain Parenchymal Cerebrospinal Fluid Circulation in Nonhuman Primate.

PubMed

Goulay, Romain; Flament, Julien; Gauberti, Maxime; Naveau, Michael; Pasquet, Nolwenn; Gakuba, Clement; Emery, Evelyne; Hantraye, Philippe; Vivien, Denis; Aron-Badin, Romina; Gaberel, Thomas

2017-08-01

Subarachnoid hemorrhage (SAH) is a devastating form of stroke with neurological outcomes dependent on the occurrence of delayed cerebral ischemia. It has been shown in rodents that some of the mechanisms leading to delayed cerebral ischemia are related to a decreased circulation of the cerebrospinal fluid (CSF) within the brain parenchyma. Here, we evaluated the cerebral circulation of the CSF in a nonhuman primate in physiological condition and after SAH. We first evaluated in physiological condition the circulation of the brain CSF in Macaca facicularis , using magnetic resonance imaging of the temporal DOTA-Gd distribution after its injection into the CSF. Then, animals were subjected to a minimally invasive SAH before an MRI evaluation of the impact of SAH on the brain parenchymal CSF circulation. We first demonstrate that the CSF actively penetrates the brain parenchyma. Two hours after injection, almost the entire brain is labeled by DOTA-Gd. We also show that our model of SAH in nonhuman primate displays the characteristics of SAH in humans and leads to a dramatic impairment of the brain parenchymal circulation of the CSF. The CSF actively penetrates within the brain parenchyma in the gyrencephalic brain, as described for the glymphatic system in rodent. This parenchymal CSF circulation is severely impaired by SAH. © 2017 American Heart Association, Inc.

Bryophyte Species Richness on Retention Aspens Recovers in Time but Community Structure Does Not

PubMed Central

Oldén, Anna; Ovaskainen, Otso; Kotiaho, Janne S.; Laaka-Lindberg, Sanna; Halme, Panu

2014-01-01

Green-tree retention is a forest management method in which some living trees are left on a logged area. The aim is to offer ‘lifeboats’ to support species immediately after logging and to provide microhabitats during and after forest re-establishment. Several studies have shown immediate decline in bryophyte diversity after retention logging and thus questioned the effectiveness of this method, but longer term studies are lacking. Here we studied the epiphytic bryophytes on European aspen (Populus tremula L.) retention trees along a 30-year chronosequence. We compared the bryophyte flora of 102 ‘retention aspens’ on 14 differently aged retention sites with 102 ‘conservation aspens’ on 14 differently aged conservation sites. We used a Bayesian community-level modelling approach to estimate the changes in bryophyte species richness, abundance (area covered) and community structure during 30 years after logging. Using the fitted model, we estimated that two years after logging both species richness and abundance of bryophytes declined, but during the following 20–30 years both recovered to the level of conservation aspens. However, logging-induced changes in bryophyte community structure did not fully recover over the same time period. Liverwort species showed some or low potential to benefit from lifeboating and high potential to re-colonise as time since logging increases. Most moss species responded similarly, but two cushion-forming mosses benefited from the logging disturbance while several weft- or mat-forming mosses declined and did not re-colonise in 20–30 years. We conclude that retention trees do not function as equally effective lifeboats for all bryophyte species but are successful in providing suitable habitats for many species in the long-term. To be most effective, retention cuts should be located adjacent to conservation sites, which may function as sources of re-colonisation and support the populations of species that require old

Is there a crisis in nursing retention in New South Wales?

PubMed Central

Doiron, Denise; Hall, Jane; Jones, Glenn

2008-01-01

Background There is a severe shortage of nurses in Australia. Policy makers and researchers are especially concerned that retention levels of nurses in the health workforce have worsened over the last decade. There are also concerns that rapidly growing private sector hospitals are attracting qualified nurses away from the public sector. To date no systematic analysis of trends in nursing retention rates over time has been conducted due to the lack of consistent panel data. Results A 1.4 percentage point improvement in retention has led to a 10% increase in the overall supply of nurses in NSW. There has also been a substantial aging of the workforce, due to greater retention and an increase in mature age entrants. The improvement in retention is found in all types of premises and is largest in nursing homes. There is a substantial amount of year to year movement in and out of the workforce and across premises. The shortage of nurses in public hospitals is due to a slowdown in entry rather than competition from the rapidly growing private sector hospitals. Policy Implications The finding of an improvement (rather than a worsening) in retention suggests that additional improvements may be difficult to achieve as further retention must involve individuals more and more dissatisfied with nursing relative to other opportunities. Hence policies targeting entry such as increased places in nursing programs and additional subsidies for training costs may be more effective in dealing with the workforce shortage. This is also the case for shortages in public sector hospitals as retention in nursing is found to be relatively high in this sector. However, the large amount of year to year movements across nursing jobs, especially among the younger nurses, also suggests that policies aimed at reducing job switches and increasing the number who return to nursing should also be pursued. More research is needed in understanding the relative importance of detailed working conditions

Competing retention pathways of uranium upon reaction with Fe(II)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Massey, Michael S.; Lezama Pacheco, Juan S.; Jones, Morris

Biogeochemical retention processes, including adsorption, reductive precipitation, and incorporation into host minerals, are important in contaminant transport, remediation, and geologic deposition of uranium. Recent work has shown that U can become incorporated into iron (hydr)oxide minerals, with a key pathway arising from Fe(II)-induced transformation of ferrihydrite, (Fe(OH)3•nH2O) to goethite (α-FeO(OH)); this is a possible U retention mechanism in soils and sediments. Several key questions, however, remain unanswered regarding U incorporation into iron (hydr)oxides and this pathway’s contribution to U retention, including: (i) the competitiveness of U incorporation versus reduction to U(IV) and subsequent precipitation of UO2; (ii) the oxidation statemore » of incorporated U; (iii) the effects of uranyl aqueous speciation on U incorporation; and, (iv) the mechanism of U incorporation. Here we use a series of batch reactions conducted at pH ~7, [U(VI)] from 1 to 170 μM, [Fe(II)] from 0 to 3 mM, and [Ca] at 0 or 4 mM) coupled with spectroscopic examination of reaction products of Fe(II)-induced ferrihydrite transformation to address these outstanding questions. Uranium retention pathways were identified and quantified using extended x-ray absorption fine structure (EXAFS) spectroscopy, x-ray powder diffraction, x-ray photoelectron spectroscopy, and transmission electron microscopy. Analysis of EXAFS spectra showed that 14 to 89% of total U was incorporated into goethite, upon reaction with Fe(II) and ferrihydrite. Uranium incorporation was a particularly dominant retention pathway at U concentrations ≤ 50 μM when either uranyl-carbonato or calcium-uranyl-carbonato complexes were dominant, accounting for 64 to 89% of total U. With increasing U(VI) and Fe(II) concentrations, U(VI) reduction to U(IV) became more prevalent, but U incorporation remained a functioning retention pathway. These findings highlight the potential importance of U

Deuterium retention and release behaviours of tungsten and deuterium co-deposited layers

NASA Astrophysics Data System (ADS)

Qiao, L.; Zhang, H. W.; Xu, J.; Chai, L. Q.; Hu, M.; Wang, P.

2018-04-01

Tungsten (W) layer deposited in argon and deuterium atmosphere by magnetron sputtering was used as a model system to study the deuterium (D) retention and release behavior in co-deposited W layer. After deposition several selected samples were exposed in deuterium plasma at 370 K with a flux of 4.0 × 1021 D/(m2 s) up to a fluence of 1.1 × 1025 D/m2. Structures of co-deposited W layers are investigated by field-emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD), and the corresponding D retention and release behaviors are studied as functions of deposition and exposure parameters using thermal desorption spectroscopy (TDS). Two main D release peaks were detected from TDS spectra located near 600 and 800 K in these W and D co-deposited layers, and total deuterium retention increased linearly as a function of W layer's thickness. After deuterium plasma exposure, the total D retention amount in W layer increases significantly and D release peak shifts to lower temperature. Clearly, despite the high density of defects expected in co-deposited W layers, the initial deuterium retention before exposure to the deuterium plasma is low even for the samples with a W&D layer. But due to the high densities of defects, during the deuterium plasma exposure the deuterium retention increases faster for co-deposited layer than for the bulk W sample.

How Students "Stay the Course": Retention Practices in Higher Education

ERIC Educational Resources Information Center

Kurantowicz, Ewa; Nizinska, Adrianna

2013-01-01

The article is based on the results of research carried out under the RANLHE project in several Polish academic institutions. Applying the biographical research approach, the project aimed to explore and understand the access and retention-related experiences of non-traditional students. In a study of non-traditional students, three distinct…

Fructo-oligosaccharides and calcium absorption and retention in adolescent girls.

PubMed

Martin, Berdine R; Braun, Michelle M; Wigertz, Karin; Bryant, Rebecca; Zhao, Yongdong; Lee, WangHee; Kempa-Steczko, Ania; Weaver, Connie M

2010-08-01

Several studies have shown a positive effect of fructo-oligosaccharides on calcium absorption and retention in animals and humans. Effects of levels of these pre-biotics that can be functionally incorporated into manufactured foods, have not been studied in controlled feeding studies. This study was designed to evaluate the effect of 9 g/d of fructo-oligosaccharides as part of a controlled diet on calcium absorption and retention in adolescent girls. Fourteen healthy adolescent girls aged 11-13 y were studied in a metabolic setting for two 3-week periods separated by a 2-week washout period. In a randomized, double-blinded, crossover design, the teens received a diet containing either 9 g/d oligofructose-enriched inulin in a calcium-fortified cereal or the control cereal with no inulin. Both diets contained ~1500 mg calcium daily. Calcium retention was determined on the third week of each period. On day 14 of the diet period, fractional calcium absorption was determined from the enrichment of (44)Ca in 4-day urine collections. Calcium absorption (67 ± 3 vs. 66 ± 3%) and retention (409 ± 394 vs. 464 ± 241 mg/d) were not significantly different when diets contained 9 g/d oligofructose-enriched inulin or not in a calcium-fortified cereal. Daily consumption of cereal containing a combination of short- and long-chain fructo-oligosaccharides as part of a controlled diet did not benefit calcium absorption or retention in adolescent girls. Lack of response to the prebiotic in this cohort may relate to their already high calcium absorption efficiency.

Retention capacity of correlated surfaces.

PubMed

Schrenk, K J; Araújo, N A M; Ziff, R M; Herrmann, H J

2014-06-01

We extend the water retention model [C. L. Knecht et al., Phys. Rev. Lett. 108, 045703 (2012)] to correlated random surfaces. We find that the retention capacity of discrete random landscapes is strongly affected by spatial correlations among the heights. This phenomenon is related to the emergence of power-law scaling in the lake volume distribution. We also solve the uncorrelated case exactly for a small lattice and present bounds on the retention of uncorrelated landscapes.

Retention of long-term interim restorations with sodium fluoride enriched interim cement

NASA Astrophysics Data System (ADS)

Strash, Carolyn

Purpose: Interim fixed dental prostheses, or "provisional restorations", are fabricated to restore teeth when definitive prostheses are made indirectly. Patients undergoing extensive prosthodontic treatment frequently require provisionalization for several months or years. The ideal interim cement would retain the restoration for as long as needed and still allow for ease of removal. It would also avoid recurrent caries by preventing demineralization of tooth structure. This study aims to determine if adding sodium fluoride varnish to interim cement may assist in the retention of interim restorations. Materials and methods: stainless steel dies representing a crown preparation were fabricated. Provisional crowns were milled for the dies using CAD/CAM technology. Crowns were provisionally cemented onto the dies using TempBond NE and NexTemp provisional cements as well as a mixture of TempBond NE and Duraphat fluoride varnish. Samples were stored for 24h then tested or thermocycled for 2500 or 5000 cycles before being tested. Retentive strength of each cement was recorded using a universal testing machine. Results: TempBond NE and NexTemp cements performed similarly when tested after 24h. The addition of Duraphat significantly decreased the retention when added to TempBond NE. NexTemp cement had high variability in retention over all tested time periods. Thermocycling for 2500 and 5000 cycles significantly decreased the retention of all cements. Conclusions: The addition of Duraphat fluoride varnish significantly decreased the retention of TempBond NE and is therefore not recommended for clinical use. Thermocycling significantly reduced the retention of TempBond NE and NexTemp. This may suggest that use of these cements for three months, as simulated in this study, is not recommended.

Fluid composition and acute kidney injury.

PubMed

Zampieri, Fernando G; Libório, Alexandre B; Cavalcanti, Alexandre B

2016-12-01

To describe recent advances in the understanding of the role of fluid composition in renal outcomes in critically ill patients. The debate on fluid composition is now focused in a pragmatic discussion on fluid electrolyte composition. The resurgence of this debate was propelled by several observational studies that suggested that balanced (i.e., low chloride) solutions were associated with less acute kidney injury in critically ill patients. Nevertheless, a cluster randomized trial failed to show any benefit of balanced solutions. This trial, however, may have failed to detect an effect because of low global illness severity and little fluid infused. If balanced solutions are to be associated with less acute kidney injury, it will probably be in high risk, aggressively resuscitated patients. Additionally, the causal loop involving unbalanced solution infusion, induction of hyperchloremia and acute kidney injury is yet to be closed. Other factors, such as buffer type, speed of infusion and temperature, among others, may also be important. Recent evidence suggests that crystalloid fluid composition matters and can influence renal outcomes in critically ill patients. Further studies should assess the impact and cost-efficiency of balanced solutions in the context of high-risk scenarios.

Persistence-Retention. Snapshot™ Report, Spring 2014

ERIC Educational Resources Information Center

National Student Clearinghouse, 2014

2014-01-01

This snapshot report provides information on student persistence and retention rates for Spring 2014. Data is presented in tabular format on the following: (1) First-Year Persistence and Retention Rates by Starting Enrollment Intensity (all institutional sectors); (2) First-Year Persistence and Retention Rates by Age at College Entry (all…

Regulation of body fluid volume and electrolyte concentrations in spaceflight.

PubMed

Smith, S M; Krauhs, J M; Leach, C S

1997-01-01

Despite a number of difficulties in performing experiments during weightlessness, a great deal of information has been obtained concerning the effects of spaceflight on the regulation of body fluid and electrolytes. Many paradoxes and questions remain, however. Although body mass, extracellular fluid volume, and plasma volume are reduced during spaceflight and remain so at landing, the changes in total body water are comparatively small. Serum or plasma sodium and osmolality have generally been unchanged or reduced during the spaceflight, and fluid intake is substantially reduced, especially during the first of flight. The diuresis that was predicted to be caused by weightlessness, has only rarely been observed as an increased urine volume. What has been well established by now, is the occurrence of a relative diuresis, where fluid intake decreases more than urine volume does. Urinary excretion of electrolytes has been variable during spaceflight, but retention of fluid and electrolytes at landing has been consistently observed. The glomerular filtration rate was significantly elevated during the SLS missions, and water and electrolyte loading tests have indicated that renal function is altered during readaptation to Earth's gravity. Endocrine control of fluid volumes and electrolyte concentrations may be altered during weightlessness, but levels of hormones in body fluids do not conform to predictions based on early hypotheses. Antidiuretic hormone is not suppressed, though its level is highly variable and its secretion may be affected by space motion sickness and environmental factors. Plasma renin activity and aldosterone are generally elevated at landing, consistent with sodium retention, but inflight levels have been variable. Salt intake may be an important factor influencing the levels of these hormones. The circadian rhythm of cortisol has undoubtedly contributed to its variability, and little is known yet about the influence of spaceflight on circadian

Regulation of body fluid volume and electrolyte concentrations in spaceflight

NASA Technical Reports Server (NTRS)

Smith, S. M.; Krauhs, J. M.; Leach, C. S.

1997-01-01

Despite a number of difficulties in performing experiments during weightlessness, a great deal of information has been obtained concerning the effects of spaceflight on the regulation of body fluid and electrolytes. Many paradoxes and questions remain, however. Although body mass, extracellular fluid volume, and plasma volume are reduced during spaceflight and remain so at landing, the changes in total body water are comparatively small. Serum or plasma sodium and osmolality have generally been unchanged or reduced during the spaceflight, and fluid intake is substantially reduced, especially during the first of flight. The diuresis that was predicted to be caused by weightlessness, has only rarely been observed as an increased urine volume. What has been well established by now, is the occurrence of a relative diuresis, where fluid intake decreases more than urine volume does. Urinary excretion of electrolytes has been variable during spaceflight, but retention of fluid and electrolytes at landing has been consistently observed. The glomerular filtration rate was significantly elevated during the SLS missions, and water and electrolyte loading tests have indicated that renal function is altered during readaptation to Earth's gravity. Endocrine control of fluid volumes and electrolyte concentrations may be altered during weightlessness, but levels of hormones in body fluids do not conform to predictions based on early hypotheses. Antidiuretic hormone is not suppressed, though its level is highly variable and its secretion may be affected by space motion sickness and environmental factors. Plasma renin activity and aldosterone are generally elevated at landing, consistent with sodium retention, but inflight levels have been variable. Salt intake may be an important factor influencing the levels of these hormones. The circadian rhythm of cortisol has undoubtedly contributed to its variability, and little is known yet about the influence of spaceflight on circadian

[Retention and biomechanics of retentive complexes. 3. The Kratochvil school and current retentive complexes].

PubMed

Enrique Fernández, M; Jacques Grimonster, L

1989-04-01

The authors analyse the biomechanical bases of the Kratochvil "retentive complex" and show how they have induced the nowadays north-american propositions (RPI & RPA). They compare them to the european ones (Nally-Martinet).

Retention of colonoscopy skills after virtual reality simulator training by independent and proctored methods.

PubMed

Snyder, Christopher W; Vandromme, Marianne J; Tyra, Sharon L; Hawn, Mary T

2010-07-01

Virtual reality (VR) simulators may enhance surgical resident colonoscopy skills, but the duration of skill retention and the effects of different simulator training methods are unknown. Medical students participating in a randomized trial of independent (automated simulator feedback only) versus proctored (human expert feedback plus simulator feedback) simulator training performed a standardized VR colonoscopy scenario at baseline, at the end of training (posttraining), and after a median 4.5 months without practice (retention). Performances were scored on a 10-point scale based on expert proficiency criteria and compared for the independent and proctored groups. Thirteen trainees (8 proctored, 5 independent) were included. Performance at retention testing was significantly better than baseline (median score 10 vs. 5, P < 0.0001), and no different from posttraining (median score 10 vs. 10, P = 0.19). Score changes from baseline to retention and from posttraining to retention were no different for the proctored and independent groups. Overinsufflation and excessive force were the most common reasons for nonproficiency at retention. After proficiency-based VR simulator training, colonoscopy skills are retained for several months, regardless of whether an independent or proctored approach is used. Error avoidance skills may not be retained as well as speed and efficiency skills.

Choice of Fluid Therapy in the Initial Management of Sepsis, Severe Sepsis, and Septic Shock.

PubMed

Chang, Ronald; Holcomb, John B

2016-07-01

Sepsis results in disruption of the endothelial glycocalyx layer and damage to the microvasculature, resulting in interstitial accumulation of fluid and subsequently edema. Fluid resuscitation is a mainstay in the initial treatment of sepsis, but the choice of fluid is unclear. The ideal resuscitative fluid is one that restores intravascular volume while minimizing edema; unfortunately, edema and edema-related complications are common consequences of current resuscitation strategies. Crystalloids are recommended as first-line therapy, but the type of crystalloid is not specified. There is increasing evidence that normal saline is associated with increased mortality and kidney injury; balanced crystalloids may be a safer alternative. Albumin is similar to crystalloids in terms of outcomes in the septic population but is costlier. Hydroxyethyl starches appear to increase mortality and kidney injury in the critically ill and are no longer indicated in these patients. In the trauma population, the shift to plasma-based resuscitation with decreased use of crystalloid and colloid in the treatment of hemorrhagic shock has led to decreased inflammatory and edema-mediated complications. Studies are needed to determine if these benefits also occur with a similar resuscitation strategy in the setting of sepsis.

Persistence-Retention. Snapshot™ Report, Spring 2015

ERIC Educational Resources Information Center

National Student Clearinghouse, 2015

2015-01-01

This Snapshot Report offers information on student persistence and retention rates for 2009-2013. It offers data on the following: (1) First-Year Persistence and Retention Rates for Students Who Start College at Four-Year Private Nonprofit Institutions; (2) First-Year Persistence and Retention Rates for Students Who Start College at Four-Year…

Occurrence of turbulent flow conditions in supercritical fluid chromatography.

PubMed

De Pauw, Ruben; Choikhet, Konstantin; Desmet, Gert; Broeckhoven, Ken

2014-09-26

Having similar densities as liquids but with viscosities up to 20 times lower (higher diffusion coefficients), supercritical CO2 is the ideal (co-)solvent for fast and/or highly efficient separations without mass-transfer limitations or excessive column pressure drops. Whereas in liquid chromatography the flow remains laminar in both the packed bed and tubing, except in extreme cases (e.g. in a 75 μm tubing, pure acetonitrile at 5 ml/min), a supercritical fluid can experience a transition from laminar to turbulent flow in more typical operation modes. Due to the significant lower viscosity, this transition for example already occurs at 1.3 ml/min for neat CO2 when using connection tubing with an ID of 127 μm. By calculating the Darcy friction factor, which can be plotted versus the Reynolds number in a so-called Moody chart, typically used in fluid dynamics, higher values are found for stainless steel than PEEK tubing, in agreement with their expected higher surface roughness. As a result turbulent effects are more pronounced when using stainless steel tubing. The higher than expected extra-column pressure drop limits the kinetic performance of supercritical fluid chromatography and complicates the optimization of tubing ID, which is based on a trade-off between extra-column band broadening and pressure drop. One of the most important practical consequences is the non-linear increase in extra-column pressure drop over the tubing downstream of the column which leads to an unexpected increase in average column pressure and mobile phase density, and thus decrease in retention. For close eluting components with a significantly different dependence of retention on density, the selectivity can significantly be affected by this increase in average pressure. In addition, the occurrence of turbulent flow is also observed in the detector cell and connection tubing. This results in a noise-increase by a factor of four when going from laminar to turbulent flow (e.g. going

Role of nocturnal rostral fluid shift in the pathogenesis of obstructive and central sleep apnoea.

PubMed

White, Laura H; Bradley, T Douglas

2013-03-01

Obstructive sleep apnoea (OSA) is common in the general population and increases the risk of motor vehicle accidents due to hypersomnolence from sleep disruption, and risk of cardiovascular diseases owing to repetitive hypoxia, sympathetic nervous system activation, and systemic inflammation. In contrast, central sleep apnoea (CSA) is rare in the general population. Although their pathogenesis is multifactorial, the prevalence of both OSA and CSA is increased in patients with fluid retaining states, especially heart failure, where they are associated with increased mortality risk. This observation suggests that fluid retention may contribute to the pathogenesis of both OSA and CSA. According to this hypothesis, during the day fluid accumulates in the intravascular and interstitial spaces of the legs due to gravity, and upon lying down at night redistributes rostrally, again owing to gravity. Some of this fluid may accumulate in the neck, increasing tissue pressure and causing the upper airway to narrow, thereby increasing its collapsibility and predisposing to OSA. In heart failure patients, with increased rostral fluid shift, fluid may additionally accumulate in the lungs, provoking hyperventilation and hypocapnia, driving below the apnoea threshold, leading to CSA. This review article will explore mechanisms by which overnight rostral fluid shift, and its prevention, can contribute to the pathogenesis and therapy of sleep apnoea.

Role of nocturnal rostral fluid shift in the pathogenesis of obstructive and central sleep apnoea

PubMed Central

White, Laura H; Bradley, T Douglas

2013-01-01

Obstructive sleep apnoea (OSA) is common in the general population and increases the risk of motor vehicle accidents due to hypersomnolence from sleep disruption, and risk of cardiovascular diseases owing to repetitive hypoxia, sympathetic nervous system activation, and systemic inflammation. In contrast, central sleep apnoea (CSA) is rare in the general population. Although their pathogenesis is multifactorial, the prevalence of both OSA and CSA is increased in patients with fluid retaining states, especially heart failure, where they are associated with increased mortality risk. This observation suggests that fluid retention may contribute to the pathogenesis of both OSA and CSA. According to this hypothesis, during the day fluid accumulates in the intravascular and interstitial spaces of the legs due to gravity, and upon lying down at night redistributes rostrally, again owing to gravity. Some of this fluid may accumulate in the neck, increasing tissue pressure and causing the upper airway to narrow, thereby increasing its collapsibility and predisposing to OSA. In heart failure patients, with increased rostral fluid shift, fluid may additionally accumulate in the lungs, provoking hyperventilation and hypocapnia, driving below the apnoea threshold, leading to CSA. This review article will explore mechanisms by which overnight rostral fluid shift, and its prevention, can contribute to the pathogenesis and therapy of sleep apnoea. PMID:23230237

"The nurse satisfaction, service quality and nurse retention chain": implications for management of recruitment and retention.

PubMed

Newman, Karin; Maylor, Uvanney; Chansarkar, Bal

2002-01-01

This paper presents the findings of a qualitative study, based on interviews with over 130 nurses and midwives in four London Trust hospitals on: the main factors influencing nurse satisfaction and retention; empirical support for the robustness of a conceptual framework or model "the nurse satisfaction, service quality and nurse retention chain"; and some managerial considerations for recruitment and retention. The three main factors influencing job satisfaction were patients, the inherent characteristics of nursing and the nursing team; the two main sources of job dissatisfaction were staff shortages and poor management and amongst nurse retention strategies improving working conditions was more important than increased pay. For recruitment, as well as retention, improving the image and reputation of nursing along with improvements in work-life balance were pre-requisites for meeting the challenging target of an additional 20,000 nurses on the wards by 2004.

The Successful Mobilization of a Campus Community for Student Retention. Report of the University Retention Steering Committee.

ERIC Educational Resources Information Center

Eastern Michigan Univ., Ypsilanti.

Components of a student retention program at Eastern Michigan University are examined; for each effort to improve retention, project objectives and design, results, and recommendations are presented. Retention initiatives, decided upon as a result of a campus-wide mobilization of effort, include: a student-focused orientation system, a fast track…

12 CFR 202.12 - Record retention.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 12 Banks and Banking 2 2010-01-01 2010-01-01 false Record retention. 202.12 Section 202.12 Banks... OPPORTUNITY ACT (REGULATION B) § 202.12 Record retention. (a) Retention of prohibited information. A creditor...) Applications. For 25 months (12 months for business credit, except as provided in paragraph (b)(5) of this...

Procalcitonin levels in patients with positive blood culture, positive body fluid culture, sepsis, and severe sepsis: a cross-sectional study.

PubMed

Yu, Ying; Li, Xia-Xi; Jiang, Ling-Xiao; Du, Meng; Liu, Zhan-Guo; Cen, Zhong-Ran; Wang, Hua; Guo, Zhen-Hui; Chang, Ping

2016-01-01

Numerous investigations on procalcitonin (PCT) have been carried out, although few with large sample size. To deal with the complexity of sepsis, an understanding of PCT in heterogeneous clinical conditions is required. Hospitalized patients aged 10-79 years were included in this retrospective and cross-sectional study. PCT tests were assayed within 2 days of blood culture. A total of 2952 cases (from 2538 patients) were enrolled in this study, including 440 cases in the 'positive BC' group, 123 cases in the 'positive body fluid culture' group, and 2389 cases in the 'negative all culture' group. Median PCT values were 4.53 ng/ml, 2.95 ng/ml, and 0.49 ng/ml, respectively. Median PCT values in the gram-negative BC group and gram-positive BC group, respectively, were 6.99 ng/ml and 2.96 ng/ml. Median PCT values in the 'positive hydrothorax culture' group, 'positive ascites culture' group, 'positive bile culture' group, and 'positive cerebrospinal fluid culture' group, respectively, were 1.39 ng/ml, 8.32 ng/ml, 5.98 ng/ml, and 0.46 ng/ml. In all, 357 cases were classified into the 'sepsis' group, 150 of them were classified into the 'severe sepsis' group. Median PCT values were 5.63 ng/ml and 11.06 ng/ml, respectively. PCT could be used in clinical algorithms to diagnose positive infections and sepsis. Different PCT levels could be related to different kinds of microbemia, different infection sites, and differing severity of sepsis.

Urinary retention during combined treatment of postpsychotic depression with duloxetine and olanzapine.

PubMed

Englisch, Susanne; Fritzinger, Michael; Zink, Mathias

2008-01-01

Duloxetine, a dual-reuptake inhibitor of serotonin and norepinephrine, has been approved for the treatment of major depressive episodes and for female stress urinary incontinence. At present, only sparse experiences are available regarding antidepressive treatment in patients with a psychotic lifetime diagnose, whereas this group of patients often suffer from major depressive episodes. Here, we describe the first case of a male patient with postpsychotic depression who developed the severe side effect of urinary retention during antidepressive treatment with duloxetine combined with olanzapine. After remission of his psychotic episode, the patient presented with depressed mood, psychomotor inhibition, sleep disturbance, and suicidal ideas. Without changing the antipsychotic therapy, we implemented duloxetine (60 mg/d) and the patient significantly improved. However, he increasingly suffered from obstructive voiding difficulties and complained about a weak urinary stream and incomplete voiding leading to unacceptable dribbling. The urinary retention disappeared completely within 1 week after discontinuation of duloxetine. We switched to venlafaxine (150 mg/d) and were able to keep the depression in remission. This case report demonstrates for the first time the onset of urinary retention in postpsychotic depression and during combined treatment with duloxetine and olanzapine. We therefore suggest increased attention on voiding function in particular if several pharmacological agents are combined.

Factors associated with severity of sleep apnoea syndrome in patients with chronic kidney disease.

PubMed

Tanaka, Akihito; Inaguma, Daijo; Ito, Eri; Kamegai, Naoki; Kato, Akiko; Mizutani, Minami; Shimogushi, Hiroya; Shinjo, Hibiki; Otsuka, Yasuhiro; Takeda, Asami

2017-08-01

Background In patients with chronic kidney disease (CKD), prevalence of sleep apnoea syndrome (SAS) is reported to be markedly high. However, the factors associated with severity of SAS in such patients rarely have been reported. Methods This was a cross-sectional study of 100 stable non-dialysis patients with CKD who attended a CKD educational programme from April 2014 to August 2015. Diagnosis of SAS and its severity were assessed using a type-3 portable monitor. Results Eighty-six men and 14 women with a mean age of 71.6 ± 9.7 years were included. Mean apnoea-hypopnoea index (AHI) was 26.0 ± 13.8. Severe SAS was seen in 39 patients. Significant differences in brain natriuretic peptide (BNP) level (213.6 ± 329.6 pg/mL vs 107.8 ± 141.3 pg/mL, P < 0.05) and cardiothoracic ratio (CTR, 52.4% ± 6.3% vs 49.6% ± 5.7%, P < 0.05) were seen between patients with and without severe SAS. After adjusting for various parameters, BNP level, CTR, and diameter of the inferior vena cava at the end of inhalation were found to correlate with AHI. Conclusions In patients with CKD, prevalence of severe SAS is extremely high. In these patients, fluid retention, rather than systolic or diastolic function, correlates with severity of SAS.

Particle-fluid interactions for flow measurements

NASA Technical Reports Server (NTRS)

Berman, N. S.

1973-01-01

Study has been made of the motion of single particle and of group of particles, emphasizing solid particles in gaseous fluid. Velocities of fluid and particle are compared for several conditions of physical interest. Mean velocity and velocity fluctuations are calculated for single particle, and some consideration is given to multiparticle systems.

Retention of Emergency Care Knowledge.

ERIC Educational Resources Information Center

Burckes, Mardie E.; Shao, Kung Ping Pam

1984-01-01

Data on the emergency care knowledge of college students were measured by a pretest, posttest, and retention test. A high relationship was found between students' posttest scores and retention test scores. Findings are discussed. (Author/DF)

Retention challenge facing Australia's rural community mental health services: Service managers' perspectives.

PubMed

Cosgrave, Catherine; Hussain, Rafat; Maple, Myfanwy

2015-10-01

This paper aims to contribute to the development of a more sustainable Australian rural community mental health workforce by comparing the findings from a literature search investigating impacting factors on retention with the experiences of community mental health service managers running services in rural Australia. Semi-structured interviews. Public health sector, rural New South Wales. Five community mental health managers, running services in rural Australia. Interviews were undertaken as a pilot for a broader qualitative study investigating factors influencing the decision to stay or leave among community mental health professionals working in rural positions. The purpose of undertaking this pilot study was to test for validity and relevance of the retention phenomena and help inform the research design for the main study. Three key retention focussed themes were identified: (i) Staffing is a persistent challenge; (ii) Small remote towns pose the biggest challenge; and (iii) The decision to stay or leave is complex and multifactorial. The findings of this pilot study support previous research and contribute to the understanding of influences on retention among health professionals working in rural community mental health services. Importantly, those who have worked for several years in rural positions hold important information through which to explore factors that impact retention in rural and remote regions. © 2015 National Rural Health Alliance Inc.

Distress tolerance interacts with circumstances, motivation, and readiness to predict substance abuse treatment retention.

PubMed

Ali, Bina; Green, Kerry M; Daughters, Stacey B; Lejuez, C W

2017-10-01

Our understanding of the conditions that influence substance abuse treatment retention in urban African American substance users is limited. This study examined the interacting effect of circumstances, motivation, and readiness (CMR) with distress tolerance to predict substance abuse treatment retention in a sample of urban African American treatment-seeking substance users. Data were collected from 81 African American substance users entering residential substance abuse treatment facility in an urban setting. Participants completed self-reported measures on CMR and distress tolerance. In addition, participants were assessed on psychiatric comorbidities, substance use severity, number of previous treatments, and demographic characteristics. Data on substance abuse treatment retention were obtained using administrative records of the treatment center. Logistic regression analysis found that the interaction of CMR and distress tolerance was significant in predicting substance abuse treatment retention. Higher score on CMR was significantly associated with increased likelihood of treatment retention in substance users with higher distress tolerance, but not in substance users with lower distress tolerance. Findings of the study indicate that at higher level of distress tolerance, favorable external circumstances, higher internal motivation, and greater readiness to treatment are important indicators of substance abuse treatment retention. The study highlights the need for assessing CMR and distress tolerance levels among substance users entering treatment, and providing targeted interventions to increase substance abuse treatment retention and subsequent recovery from substance abuse among urban African American substance users. Copyright © 2017 Elsevier Ltd. All rights reserved.

Integrated fountain effect pump device for fluid management at low gravity

NASA Technical Reports Server (NTRS)

Yuan, S. W. K.; Frank, D. J.

1988-01-01

A new device for fluid management at low gravity is described. The system is basically the same as the enclosed capillary device using screens, in which the screens along the gallery channels are replaced by porous plugs which are responsible for both the fluid retention and pumping of He II; in this device, no downstream pump is needed. The plugs in contact with liquid He on both sides act as a fountain-effect pumps (FEPs), while plugs exposed to vapor on one side behave as vapor-liquid phase separators (VLPSs). The total net rate of He II transfer into the receiving tank equals the mass flow rate through the FEP plugs minus the liquid loss from the VLPS plugs. The results of the performance analysis of this integrated FEP device are presented together with its schematic diagram.

Fluid Overload and Fluid Removal in Pediatric Patients on Extracorporeal Membrane Oxygenation Requiring Continuous Renal Replacement Therapy

PubMed Central

Selewski, David T; Cornell, Timothy T; Blatt, Neal B; Han, Yong Y; Mottes, Theresa; Kommareddi, Mallika; Gaies, Michael G; Annich, Gail M; Kershaw, David B; Shanley, Thomas P; Heung, Michael

2012-01-01

Objective In pediatric patients fluid overload (FO) at continuous renal replacement (CRRT) initiation is associated with increased mortality. The aim of this study was to characterize the association between fluid overload at CRRT initiation, fluid removal during CRRT, the kinetics of fluid removal and mortality in a large pediatric population receiving CRRT while on extracorporeal membrane oxygenation (ECMO). Design Retrospective chart review. Setting Tertiary children’s hospital Patients ECMO patients requiring CRRT from July 2006 to September 2010 Interventions None Measurements and Main Results Overall ICU survival was 34% for 53 patients that were initiated on CRRT while on ECMO during the study period. Median FO at CRRT initiation was significantly lower in survivors compared to non-survivors (24.5 vs. 38%, p=0.006). Median FO at CRRT discontinuation was significantly lower in survivors compared to non-survivors (7.1 vs. 17.5%, p=0.035). After adjusting for percent FO at CRRT initiation, age and severity of illness, the change in FO at CRRT discontinuation was not significantly associated with mortality (p=0.212). Models investigating the rates of fluid removal in different periods, age, severity of illness and fluid overload at CRRT initiation found that fluid overload at CRRT initiation was the most consistent predictor of survival. Conclusions Our data demonstrates an association between FO at CRRT initiation and mortality in pediatric patients receiving ECMO. The degree of FO at CRRT discontinuation is also associated with mortality, but appears to reflect the effect of FO at initiation. Furthermore, correction of FO to ≤ 10% was not associated with improved survival. These results suggest that intervening prior to the development of significant FO may be more clinically effective than attempting fluid removal after significant fluid overload has developed. Our findings suggest a role for earlier initiation of CRRT in this population, and warrant

Retention of iron by infants.

PubMed

Fomon, S J; Nelson, S E; Ziegler, E E

2000-01-01

Throughout the world, the most common nutritional deficiency disorder of infants is iron deficiency. Developing effective strategies for preventing iron deficiency requires detailed knowledge of iron retention under ordinary living conditions. For the adult population, such knowledge is at an advanced stage, but relatively little is known about infants. Many reports of iron retention by infants have been based on the assumption that, as in normal and iron-deficient adults, 80%-100% of newly absorbed iron is promptly incorporated into circulating erythrocytes, but this assumption is not supported by available data. This communication presents a review of iron retention by term and preterm infants, as determined by metabolic balance studies or (59)Fe whole-body counting studies, and it explores the relationship between iron retention and postnatal age, iron nutritional status, iron intake (or dose), and type of feeding.

Injuries from non-retention in gillnet fisheries suppress reproductive maturation in escaped fish.

PubMed

Baker, Matthew R; Swanson, Penny; Young, Graham

2013-01-01

Exploitation of fisheries resources has unintended consequences, not only in the bycatch and discard of non-target organisms, but also in damage to targeted fish that are injured by gear but not landed (non-retention). Delayed mortality due to non-retention represents lost reproductive potential in exploited stocks, while not contributing to harvest. Our study examined the physiological mechanisms by which delayed mortality occurs and the extent to which injuries related to disentanglement from commercial gear compromise reproductive success in spawning stocks of Pacific salmon (Oncorhynchus spp.). We found evidence for elevated stress in fish injured via non-retention in gillnet fisheries. Plasma cortisol levels correlated with the severity of disentanglement injury and were elevated in fish that developed infections related to disentanglement injuries. We also analyzed sex steroid concentrations in females (estradiol-17β and 17,20β-dihydroxy-4-pregnen-3-one) to determine whether non-retention impairs reproductive potential in escaped individuals. We demonstrate evidence for delayed or inhibited maturation in fish with disentanglement injuries. These findings have important implications for effective conservation and management of exploited fish stocks and suggest means to improve spawning success in such stocks if retention in commercial fisheries is improved and incidental mortality reduced.

Injuries from Non-Retention in Gillnet Fisheries Suppress Reproductive Maturation in Escaped Fish

PubMed Central

Baker, Matthew R.; Swanson, Penny; Young, Graham

2013-01-01

Exploitation of fisheries resources has unintended consequences, not only in the bycatch and discard of non-target organisms, but also in damage to targeted fish that are injured by gear but not landed (non-retention). Delayed mortality due to non-retention represents lost reproductive potential in exploited stocks, while not contributing to harvest. Our study examined the physiological mechanisms by which delayed mortality occurs and the extent to which injuries related to disentanglement from commercial gear compromise reproductive success in spawning stocks of Pacific salmon (Oncorhynchus spp.). We found evidence for elevated stress in fish injured via non-retention in gillnet fisheries. Plasma cortisol levels correlated with the severity of disentanglement injury and were elevated in fish that developed infections related to disentanglement injuries. We also analyzed sex steroid concentrations in females (estradiol-17β and 17,20β-dihydroxy-4-pregnen-3-one) to determine whether non-retention impairs reproductive potential in escaped individuals. We demonstrate evidence for delayed or inhibited maturation in fish with disentanglement injuries. These findings have important implications for effective conservation and management of exploited fish stocks and suggest means to improve spawning success in such stocks if retention in commercial fisheries is improved and incidental mortality reduced. PMID:23894510

5 CFR 575.306 - Authorizing a retention incentive.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Authorizing a retention incentive. 575... RECRUITMENT, RELOCATION, AND RETENTION INCENTIVES; SUPERVISORY DIFFERENTIALS; AND EXTENDED ASSIGNMENT INCENTIVES Retention Incentives § 575.306 Authorizing a retention incentive. (a) Authority of authorized...

Hypothalamic integration of body fluid regulation.

PubMed Central

Denton, D A; McKinley, M J; Weisinger, R S

1996-01-01

The progression of animal life from the paleozoic ocean to rivers and diverse econiches on the planet's surface, as well as the subsequent reinvasion of the ocean, involved many different stresses on ionic pattern, osmotic pressure, and volume of the extracellular fluid bathing body cells. The relatively constant ionic pattern of vertebrates reflects a genetic "set" of many regulatory mechanisms--particularly renal regulation. Renal regulation of ionic pattern when loss of fluid from the body is disproportionate relative to the extracellular fluid composition (e.g., gastric juice with vomiting and pancreatic secretion with diarrhea) makes manifest that a mechanism to produce a biologically relatively inactive extracellular anion HCO3- exists, whereas no comparable mechanism to produce a biologically inactive cation has evolved. Life in the ocean, which has three times the sodium concentration of extracellular fluid, involves quite different osmoregulatory stress to that in freshwater. Terrestrial life involves risk of desiccation and, in large areas of the planet, salt deficiency. Mechanisms integrated in the hypothalamus (the evolutionary ancient midbrain) control water retention and facilitate excretion of sodium, and also control the secretion of renin by the kidney. Over and above the multifactorial processes of excretion, hypothalamic sensors reacting to sodium concentration, as well as circumventricular organs sensors reacting to osmotic pressure and angiotensin II, subserve genesis of sodium hunger and thirst. These behaviors spectacularly augment the adaptive capacities of animals. Instinct (genotypic memory) and learning (phenotypic memory) are melded to give specific behavior apt to the metabolic status of the animal. The sensations, compelling emotions, and intentions generated by these vegetative systems focus the issue of the phylogenetic emergence of consciousness and whether primal awareness initially came from the interoreceptors and vegetative

Fluid Flow Phenomena during Welding

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Wei

2011-01-01

MOLTEN WELD POOLS are dynamic. Liquid in the weld pool in acted on by several strong forces, which can result in high-velocity fluid motion. Fluid flow velocities exceeding 1 m/s (3.3 ft/s) have been observed in gas tungsten arc (GTA) welds under ordinary welding conditions, and higher velocities have been measured in submerged arc welds. Fluid flow is important because it affects weld shape and is related to the formation of a variety of weld defects. Moving liquid transports heat and often dominates heat transport in the weld pool. Because heat transport by mass flow depends on the direction andmore » speed of fluid motion, weld pool shape can differ dramatically from that predicted by conductive heat flow. Temperature gradients are also altered by fluid flow, which can affect weld microstructure. A number of defects in GTA welds have been attributed to fluid flow or changes in fluid flow, including lack of penetration, top bead roughness, humped beads, finger penetration, and undercutting. Instabilities in the liquid film around the keyhole in electron beam and laser welds are responsible for the uneven penetration (spiking) characteristic of these types of welds.« less

Generating perfect fluid spheres in general relativity

NASA Astrophysics Data System (ADS)

Boonserm, Petarpa; Visser, Matt; Weinfurtner, Silke

2005-06-01

Ever since Karl Schwarzschild’s 1916 discovery of the spacetime geometry describing the interior of a particular idealized general relativistic star—a static spherically symmetric blob of fluid with position-independent density—the general relativity community has continued to devote considerable time and energy to understanding the general-relativistic static perfect fluid sphere. Over the last 90 years a tangle of specific perfect fluid spheres has been discovered, with most of these specific examples seemingly independent from each other. To bring some order to this collection, in this article we develop several new transformation theorems that map perfect fluid spheres into perfect fluid spheres. These transformation theorems sometimes lead to unexpected connections between previously known perfect fluid spheres, sometimes lead to new previously unknown perfect fluid spheres, and in general can be used to develop a systematic way of classifying the set of all perfect fluid spheres.

Job embeddedness factors and retention of nurses with 1 to 3 years of experience.

PubMed

Halfer, Diana

2011-10-01

An aging work force, predictions of job growth in health care, and an eventual economic recovery suggest that the current reprieve from the national nursing shortage is temporary. New graduate nurses are an important part of the work force and are needed to replace nurses who will retire in the next decade. Organizational leaders can address the forecasted work force demand by proactively investing in programs for workplace development and retention. Recent literature reports an increased focus on understanding the work experience and career support needed for new graduate nurses. Several studies report improvements in job satisfaction and retention after implementation of structured mentoring programs for new graduate nurses. However, despite successful transition programs, turnover for these same nurses after 1 to 3 years of organizational tenure remains high. Studying factors that contribute to retention and supporting careers beyond the first year of practice may have a significant effect on improving retention and will contribute new knowledge to the nursing literature. This study, undertaken at a Midwestern pediatric academic medical center, examined job factors and career development support that lead to retention of nurses with 1 to 3 years of experience. Understanding these issues may guide nursing leaders and staff development educators in investing in focused retention and career development plans during an economic recession. Copyright 2011, SLACK Incorporated.

Fecal retention in childhood: Evaluation on ultrasonography.

PubMed

Hatori, Reiko; Tomomasa, Takeshi; Ishige, Takashi; Tatsuki, Maiko; Arakawa, Hirokazu

2017-04-01

To assess the usefulness of rectal diameter measurement on ultrasonography as a diagnostic tool for fecal retention in children. One hundred children (median age, 5.0 years), consisting of 80 with functional constipation and 20 without constipation, participated in the study. All patients underwent physical examination that included digital rectal examination. Forty-five children underwent ultrasonography in three differential planes: transection above the symphysis; under the ischial spine; and at the bladder neck. The measurement of the rectal diameter at the transection above the symphysis could most easily detect fecal retention and had the closest correlations with retention among the three planes. Rectal diameter was wider at all measuring points (35.2 vs 20.9 mm above the symphysis, P < 0.0001; 35.7 vs 24.0 mm under the ischial spine, P < 0.0001; and 19.4 vs 8.7 mm at the bladder neck, P < 0.0001) in children with fecal retention than in those with no fecal retention. With regard to presence of constipation, children with fecal retention had a wider rectal diameter above the symphysis than those with no fecal retention (children with functional constipation, 35.3 vs 20.0 mm, P < 0.0001; children without constipation: 32.6 vs 14.6 mm, P = 0.0026). The cut-off for the rectal diameter measured above the symphysis to identify fecal retention was 27 mm, with high sensitivity and specificity (95.5% and 94.1%, respectively). Ultrasound rectal diameter measurement can be used to detect fecal retention in children. © 2016 Japan Pediatric Society.

Data Retention and Anonymity Services

NASA Astrophysics Data System (ADS)

Berthold, Stefan; Böhme, Rainer; Köpsell, Stefan

The recently introduced legislation on data retention to aid prosecuting cyber-related crime in Europe also affects the achievable security of systems for anonymous communication on the Internet. We argue that data retention requires a review of existing security evaluations against a new class of realistic adversary models. In particular, we present theoretical results and first empirical evidence for intersection attacks by law enforcement authorities. The reference architecture for our study is the anonymity service AN.ON, from which we also collect empirical data. Our adversary model reflects an interpretation of the current implementation of the EC Directive on Data Retention in Germany.

Fluid pressure responses for a Devil's Slide-like system: problem formulation and simulation

USGS Publications Warehouse

Thomas, Matthew A.; Loague, Keith; Voss, Clifford I.

2015-01-01

This study employs a hydrogeologic simulation approach to investigate subsurface fluid pressures for a landslide-prone section of the central California, USA, coast known as Devil's Slide. Understanding the relative changes in subsurface fluid pressures is important for systems, such as Devil's Slide, where slope creep can be interrupted by episodic slip events. Surface mapping, exploratory core, tunnel excavation records, and dip meter data were leveraged to conceptualize the parameter space for three-dimensional (3D) Devil's Slide-like simulations. Field observations (i.e. seepage meter, water retention, and infiltration experiments; well records; and piezometric data) and groundwater flow simulation (i.e. one-dimensional vertical, transient, and variably saturated) were used to design the boundary conditions for 3D Devil's Slide-like problems. Twenty-four simulations of steady-state saturated subsurface flow were conducted in a concept-development mode. Recharge, heterogeneity, and anisotropy are shown to increase fluid pressures for failure-prone locations by up to 18.1, 4.5, and 1.8% respectively. Previous estimates of slope stability, driven by simple water balances, are significantly improved upon with the fluid pressures reported here. The results, for a Devil's Slide-like system, provide a foundation for future investigations

20 CFR 655.167 - Document retention requirements.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Document retention requirements. 655.167... retention requirements. (a) Entities required to retain documents. All employers filing an Application for... retain the documents and records proving compliance with this subpart. (b) Period of required retention...

Molecular Mechanisms Controlling GLUT4 Intracellular Retention

PubMed Central

Blot, Vincent

2008-01-01

In basal adipocytes, glucose transporter 4 (GLUT4) is sequestered intracellularly by an insulin-reversible retention mechanism. Here, we analyze the roles of three GLUT4 trafficking motifs (FQQI, TELEY, and LL), providing molecular links between insulin signaling, cellular trafficking machinery, and the motifs in the specialized trafficking of GLUT4. Our results support a GLUT4 retention model that involves two linked intracellular cycles: one between endosomes and a retention compartment, and the other between endosomes and specialized GLUT4 transport vesicles. Targeting of GLUT4 to the former is dependent on the FQQI motif and its targeting to the latter is dependent on the TELEY motif. These two motifs act independently in retention, with the TELEY-dependent step being under the control of signaling downstream of the AS160 rab GTPase activating protein. Segregation of GLUT4 from endosomes, although positively correlated with the degree of basal retention, does not completely account for GLUT4 retention or insulin-responsiveness. Mutation of the LL motif slows return to basal intracellular retention after insulin withdrawal. Knockdown of clathrin adaptin protein complex-1 (AP-1) causes a delay in the return to intracellular retention after insulin withdrawal. The effects of mutating the LL motif and knockdown of AP-1 were not additive, establishing that AP-1 regulation of GLUT4 trafficking requires the LL motif. PMID:18550797

The PSI Artist Project: Aerosol Retention and Accident Management Issues Following a Steam Generator Tube Rupture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guntay, Salih; Dehbi, Abdel; Suckow, Detlef

2002-07-01

Steam generator tube rupture (SGTR) incidents, such as those, which occurred in various operating pressurized, water reactors in the past, are serious operational concerns and remain among the most risk-dominant events. Although considerable efforts have been spent to understand tube degradation processes, develop improved modes of operation, and take preventative and corrective measures, SGTR incidents cannot be completely ruled out. Under certain conditions, high releases of radionuclides to the environment are possible during design basis accidents (DBA) and severe accidents. The severe accident codes' models for aerosol retention in the secondary side of a steam generator (SG) have not beenmore » assessed against any experimental data, which means that the uncertainties in the source term following an un-isolated SGTR concurrent with a severe accident are not currently quantified. The accident management (AM) procedures aim at avoiding or minimizing the release of fission products from the SG. The enhanced retention of activity within the SG defines the effectiveness of the accident management actions for the specific hardware characteristics and accident conditions of concern. A sound database on aerosol retention due to natural processes in the SG is not available, nor is an assessment of the effect of management actions on these processes. Hence, the effectiveness of the AM in SGTR events is not presently known. To help reduce uncertainties relating to SGTR issues, an experimental project, ARTIST (Aerosol Trapping In a Steam generator), has been initiated at the Paul Scherrer Institut to address aerosol and droplet retention in the various parts of the SG. The test section is comprised of a scaled-down tube bundle, a full-size separator and a full-size dryer unit. The project will study phenomena at the separate effect and integral levels and address AM issues in seven distinct phases: Aerosol retention in 1) the broken tube under dry secondary side

Toward a Political Explanation of Grade Retention

ERIC Educational Resources Information Center

Bali, Valentina A.; Anagnostopoulos, Dorothea; Roberts, Reginald

2005-01-01

Policies that mandate in-grade retention of low-performing students have become central components of standards-based reforms across the country. While educational researchers have extensively studied the student-level correlates of retention and the consequences of retention for student achievement, little attention has been focused on…

A parametric study of helium retention in beryllium and its effect on deuterium retention

NASA Astrophysics Data System (ADS)

Alegre, D.; Baldwin, M. J.; Simmonds, M.; Nishijima, D.; Hollmann, E. M.; Brezinsek, S.; Doerner, R. P.

2017-12-01

Beryllium samples have been exposed in the PISCES-B linear plasma device to conditions relevant to the International Thermonuclear Experimental Reactor (ITER) in pure He, D, and D/He mixed plasmas. Except at intermediate sample exposure temperatures (573-673 K) He addition to a D plasma is found to have a beneficial effect as it reduces the D retention in Be (up to ˜55%), although the mechanism is unclear. Retention of He is typically around 1020-1021 He m-2, and is affected primarily by the Be surface temperature during exposition, by the ion fluence at <500 K exposure, but not by the ion impact energy at 573 K. Contamination of the Be surface with high-Z elements from the mask of the sample holder in pure He plasmas is also observed under certain conditions, and leads to unexpectedly large He retention values, as well as changes in the surface morphology. An estimation of the tritium retention in the Be first wall of ITER is provided, being sufficiently low to allow a safe operation of ITER.

Pinnaplasty: reshaping ears to improve hearing aid retention.

PubMed

Gault, David; Grob, Marion; Odili, Joy

2007-01-01

The hearing aid is extremely important to the deaf. A small number have difficulty in retaining the device because the ear is prominent or cup-shaped. This report describes 11 children whose ear shape was modified to improve hearing aid retention and one adult in whom an over set back ear was released to allow fitment of a postaural device. In eight of the 11 children treated, conservative measures such as double-sided tape and retention bands (Huggies) had been tried previously without success. The creation of an antihelical fold in a misshapen ear lacking such a fold provides a reinforcing strut which is useful to support a hearing aid. In patients whose ear had been excessively tethered by previous surgery, projection was restored by inserting a cartilage block behind the ear. In one child with ears tethered by previous surgery, costal cartilage was used not only to release both ears, but also to reconstruct a new helical rim on one side. Surgery enabled a normal postaural hearing aid to be worn in 17 of the 19 ears treated. The two failures deserve special mention. In one patient with a unilateral deformity and severe mental retardation, the dressings were pulled off immediately after surgery. In another patient with a bilateral problem, the appearance and hearing aid retention was improved, but there was not enough room in the postauricular sulcus on one side for the battery component to fit comfortably and an in-the-ear device is now used on that side. Pinnaplasty is a helpful strategy to improve hearing aid retention. Care must be taken not to overdo the set back so that enough room is left to retain the hearing device.

Fall 1989-Spring 1990 Retention Analysis. Enrollment Analysis EA91-3.

ERIC Educational Resources Information Center

Clagett, Craig A.

Fall-to-spring retention rates were calculated at Prince George's Community College (PGCC) for several demographic groups and for first-time students attending the college in fall 1989. Data from longitudinal studies were included to provide a more complete picture of student persistence at PGCC. Study findings included the following: (1) 60% of…

Green roof stormwater retention: effects of roof surface, slope, and media depth.

PubMed

VanWoert, Nicholaus D; Rowe, D Bradley; Andresen, Jeffrey A; Rugh, Clayton L; Fernandez, R Thomas; Xiao, Lan

2005-01-01

Urban areas generate considerably more stormwater runoff than natural areas of the same size due to a greater percentage of impervious surfaces that impede water infiltration. Roof surfaces account for a large portion of this impervious cover. Establishing vegetation on rooftops, known as green roofs, is one method of recovering lost green space that can aid in mitigating stormwater runoff. Two studies were performed using several roof platforms to quantify the effects of various treatments on stormwater retention. The first study used three different roof surface treatments to quantify differences in stormwater retention of a standard commercial roof with gravel ballast, an extensive green roof system without vegetation, and a typical extensive green roof with vegetation. Overall, mean percent rainfall retention ranged from 48.7% (gravel) to 82.8% (vegetated). The second study tested the influence of roof slope (2 and 6.5%) and green roof media depth (2.5, 4.0, and 6.0 cm) on stormwater retention. For all combined rain events, platforms at 2% slope with a 4-cm media depth had the greatest mean retention, 87%, although the difference from the other treatments was minimal. The combination of reduced slope and deeper media clearly reduced the total quantity of runoff. For both studies, vegetated green roof systems not only reduced the amount of stormwater runoff, they also extended its duration over a period of time beyond the actual rain event.

40 CFR 160.195 - Retention of records.

Code of Federal Regulations, 2012 CFR

2012-07-01

... obtained from mutagenicity tests, specimens of soil, water, and plants, and wet specimens of blood, urine... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Retention of records. 160.195 Section... LABORATORY PRACTICE STANDARDS Records and Reports § 160.195 Retention of records. (a) Record retention...

40 CFR 160.195 - Retention of records.

Code of Federal Regulations, 2014 CFR

2014-07-01

... obtained from mutagenicity tests, specimens of soil, water, and plants, and wet specimens of blood, urine... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Retention of records. 160.195 Section... LABORATORY PRACTICE STANDARDS Records and Reports § 160.195 Retention of records. (a) Record retention...

40 CFR 160.195 - Retention of records.

Code of Federal Regulations, 2013 CFR

2013-07-01

... obtained from mutagenicity tests, specimens of soil, water, and plants, and wet specimens of blood, urine... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Retention of records. 160.195 Section... LABORATORY PRACTICE STANDARDS Records and Reports § 160.195 Retention of records. (a) Record retention...

40 CFR 160.195 - Retention of records.

Code of Federal Regulations, 2011 CFR

2011-07-01

... obtained from mutagenicity tests, specimens of soil, water, and plants, and wet specimens of blood, urine... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Retention of records. 160.195 Section... LABORATORY PRACTICE STANDARDS Records and Reports § 160.195 Retention of records. (a) Record retention...

Reframing Retention Strategy: A Focus on Progress

ERIC Educational Resources Information Center

Spittle, Brian

2013-01-01

Few words have dominated the vocabulary of college retention as has the word "persistence." Many institutions still struggle to engage faculty and administrators in building campuswide retention efforts, to find the organizational levers that translate the abstractions and complexities of retention theory into scalable and durable initiatives, and…

22 CFR 50.20 - Retention of nationality.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Retention of nationality. 50.20 Section 50.20 Foreign Relations DEPARTMENT OF STATE NATIONALITY AND PASSPORTS NATIONALITY PROCEDURES Retention and Resumption of Nationality § 50.20 Retention of nationality. (a) Section 351(b) of the Immigration and...

22 CFR 50.20 - Retention of nationality.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Retention of nationality. 50.20 Section 50.20 Foreign Relations DEPARTMENT OF STATE NATIONALITY AND PASSPORTS NATIONALITY PROCEDURES Retention and Resumption of Nationality § 50.20 Retention of nationality. (a) Section 351(b) of the Immigration and...

22 CFR 50.20 - Retention of nationality.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Retention of nationality. 50.20 Section 50.20 Foreign Relations DEPARTMENT OF STATE NATIONALITY AND PASSPORTS NATIONALITY PROCEDURES Retention and Resumption of Nationality § 50.20 Retention of nationality. (a) Section 351(b) of the Immigration and...

22 CFR 50.20 - Retention of nationality.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Retention of nationality. 50.20 Section 50.20 Foreign Relations DEPARTMENT OF STATE NATIONALITY AND PASSPORTS NATIONALITY PROCEDURES Retention and Resumption of Nationality § 50.20 Retention of nationality. (a) Section 351(b) of the Immigration and...

22 CFR 50.20 - Retention of nationality.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Retention of nationality. 50.20 Section 50.20 Foreign Relations DEPARTMENT OF STATE NATIONALITY AND PASSPORTS NATIONALITY PROCEDURES Retention and Resumption of Nationality § 50.20 Retention of nationality. (a) Section 351(b) of the Immigration and...

46 CFR 308.600 - Records retention requirement.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 8 2011-10-01 2011-10-01 false Records retention requirement. 308.600 Section 308.600 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE Records Retention § 308.600 Records retention requirement. The records specified in §§ 308.8, 308.517, and...

46 CFR 308.600 - Records retention requirement.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 8 2012-10-01 2012-10-01 false Records retention requirement. 308.600 Section 308.600 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE Records Retention § 308.600 Records retention requirement. The records specified in §§ 308.8, 308.517, and...

46 CFR 308.600 - Records retention requirement.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 8 2010-10-01 2010-10-01 false Records retention requirement. 308.600 Section 308.600 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE Records Retention § 308.600 Records retention requirement. The records specified in §§ 308.8, 308.517, and...

46 CFR 308.600 - Records retention requirement.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 8 2014-10-01 2014-10-01 false Records retention requirement. 308.600 Section 308.600 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE Records Retention § 308.600 Records retention requirement. The records specified in §§ 308.8, 308.517, and...

46 CFR 308.600 - Records retention requirement.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 8 2013-10-01 2013-10-01 false Records retention requirement. 308.600 Section 308.600 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE Records Retention § 308.600 Records retention requirement. The records specified in §§ 308.8, 308.517, and...

Reframing Retention Strategy: A Focus on Profile

ERIC Educational Resources Information Center

Kalsbeek, David H.; Zucker, Brian

2013-01-01

Over 35 years of retention theory and literature have acknowledged the importance of institutional and student profiles in accounting for cross-sectional differences in retention and completion rates between types of colleges and universities. The first "P" within a 4 Ps framework of student retention--"profile"--recognizes that an institution's…

The cerebrospinal fluid proteome in HIV infection: change associated with disease severity.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Angel, Thomas E.; Jacobs, Jon M.; Spudich, Serena S.

2012-03-20

Central nervous system (CNS) infection is a constant feature of systemic HIV infection with a clinical spectrum that ranges from chronic asymptomatic infection to severe cognitive and motor dysfunction. Analysis of cerebrospinal fluid (CSF) has played an important part in defining the character of this evolving infection and response to treatment. To further characterize CNS HIV infection and its effects, we applied advanced high-throughput proteomic methods to CSF to identify novel proteins and their changes with disease progression and treatment. After establishing an accurate mass and time (AMT) tag database containing 23,141 AMT tags for CSF peptides, we analyzed 91more » CSF samples by LC-MS from 12 HIV-uninfected and 14 HIV-infected subjects studied in the context of initiation of antiretroviral and correlated abundances of identified proteins (a) within and between subjects, (b) with all other proteins across the entire sample set, and (c) with 'external' CSF biomarkers of infection (HIV RNA), immune activation (neopterin) and neural injury (neurofilament light chain protein, NFL). We identified a mean of 2,333 +/- 328 (SD) peptides covering 307 +/-16 proteins in the 91 CSF sample set. Protein abundances differed both between and within subjects sampled at different time points and readily separated those with and without HIV infection. Proteins also showed inter-correlations across the sample set that were associated with biologically relevant dynamic processes. One-hundred and fifty proteins showed correlations with the external biomarkers. For example, using a threshold of cross correlation coefficient (Pearson's) {le}0.3 and {ge}0.3 for potentially meaningful relationships, a total of 99 proteins correlated with CSF neopterin (43 negative and 56 positive correlations) and related principally to neuronal plasticity and survival and to innate immunity. Pathway analysis defined several networks connecting the identified proteins, including one with

The cerebrospinal fluid proteome in HIV infection: change associated with disease severity

PubMed Central

2012-01-01

Background Central nervous system (CNS) infection is a nearly universal feature of untreated systemic HIV infection with a clinical spectrum that ranges from chronic asymptomatic infection to severe cognitive and motor dysfunction. Analysis of cerebrospinal fluid (CSF) has played an important part in defining the character of this evolving infection and response to treatment. To further characterize CNS HIV infection and its effects, we applied advanced high-throughput proteomic methods to CSF to identify novel proteins and their changes with disease progression and treatment. Results After establishing an accurate mass and time (AMT) tag database containing 23,141 AMT tags for CSF peptides, we analyzed 91 CSF samples by LC-MS from 12 HIV-uninfected and 14 HIV-infected subjects studied in the context of initiation of antiretroviral therapy and correlated abundances of identified proteins a) within and between subjects, b) with all other proteins across the entire sample set, and c) with "external" CSF biomarkers of infection (HIV RNA), immune activation (neopterin) and neural injury (neurofilament light chain protein, NFL). We identified a mean of 2,333 +/- 328 (SD) peptides covering 307 +/-16 proteins in the 91 CSF sample set. Protein abundances differed both between and within subjects sampled at different time points and readily separated those with and without HIV infection. Proteins also showed inter-correlations across the sample set that were associated with biologically relevant dynamic processes. One-hundred and fifty proteins showed correlations with the external biomarkers. For example, using a threshold of cross correlation coefficient (Pearson's) ≤ -0.3 and ≥0.3 for potentially meaningful relationships, a total of 99 proteins correlated with CSF neopterin (43 negative and 56 positive correlations) and related principally to neuronal plasticity and survival and to innate immunity. Pathway analysis defined several networks connecting the identified

Oral versus intravenous rehydration therapy in severe gastroenteritis.

PubMed Central

Sharifi, J; Ghavami, F; Nowrouzi, Z; Fouladvand, B; Malek, M; Rezaeian, M; Emami, M

1985-01-01

A controlled, randomised trial comparing the results of oral rehydration therapy with those of intravenous fluid treatment in 470 children with severe gastroenteritis was undertaken. The oral rehydration therapy was divided into two phases--a rehydration phase that used high sodium isotonic fluid at 40 ml/kg per hour and a maintenance phase using low sodium isotonic fluid (sodium 40, potassium 30, bicarbonate 25, chloride 45, and dextrose 130 mmol/l). The results indicate that oral rehydration treatment, used according to this protocol, is successful in treating severe diarrhoea and dehydration, and has considerable advantages over intravenous fluid therapy in reducing complications associated with the treatment of hypernatraemia, in promoting rapid correction of hypokalaemia and acidosis, in decreasing the duration of diarrhoea, and in promoting a greater weight gain at hospital discharge. PMID:3901934

20 CFR 655.1319 - Document retention requirements.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Document retention requirements. 655.1319... Employment in the United States (H-2A Workers) § 655.1319 Document retention requirements. (a) Entities... retention. Records and documents must be retained for a period of 3 years from the date of certification of...

Predictors of retention in a drug-free unit/substance abuse treatment in prison.

PubMed

Casares-López, María José; González-Menéndez, Ana; Festinger, David S; Fernández-García, Paula; Fernández-Hermida, José Ramón; Secades, Roberto; Matejkowski, Jason

2013-01-01

The high rate of dropout from treatment programs is a recurring problem in the field of drug dependence. The purpose of this study was to identify the predictors of retention in a prison-based drug-free unit (DFU). The relationships among subscales of the Addiction Severity Index (ASI) as well as motivation and personality profiles and length of stay in a DFU, of 57 prisoners admitted for the first time to the program were analyzed. The mean dropout rates were 52.9% at six months and 67.8% at one year. The mean length of stay was 195.05 days. Predictors of retention at six months included the ASI Family Composite Score, the motivation subscale Taking Steps, and Narcissistic personality trait score. Predictors of retention at one year included lower ASI Psychological Composite Score, higher scores on the motivation subscale Ambivalence, and higher number of charges pending at the time of admission to the program. Identification of these predictor variables may be useful for developing strategies to increase retention in the context of in-prison substance abuse treatment. Copyright © 2013. Published by Elsevier Ltd.

Mechanisms of nutrient retention and its relation to flow connectivity in river-floodplain corridors

USGS Publications Warehouse

Larsen, Laurel; Harvey, Judson; Maglio, Morgan M.

2015-01-01

Understanding heterogeneity or patchiness in the distribution of vegetation and retention of C and nutrients in river corridors is critical for setting priorities for river management and restoration. Several mechanisms of spatial differentiation in nutrient retention in river and floodplain corridors have been recognized, but few studies have distinguished their relative importance or established their role in long-term geomorphic change, nutrient retention, and connectivity with downstream systems. We evaluated the ability of 3 mechanisms (evapotranspiration focusing [EF], differential hydrologic exchange [DHE], and particulate nutrient redistribution [PNR]) to explain spatial patterns of P retention and function in the Everglades (Florida, USA). We used field measurements in sloughs and on slightly higher, more densely vegetated ridges to quantify P fluxes attributable to the 3 mechanisms. EF does not explain Everglades nutrient retention or P concentrations on ridges and in sloughs. However, DHE resulting from different periods of groundwater–surface-water connectivity across topographic elements is the primary cause of elevated P concentrations on ridges and completely explains interpatch differences in long-term P accumulation rates. With historical flow velocities, which were an order of magnitude higher than at present, PNR would have further increased the interpatch difference in long-term P retention rates nearly 2-fold. In conclusion, DHE and PNR are the dominant drivers of nutrient patchiness in the Everglades and are hypothesized to be important in P-limited river and floodplain corridors globally.

The Fluids and Combustion Facility

NASA Technical Reports Server (NTRS)

Kundu, Sampa

2004-01-01

Microgravity is an environment with very weak gravitational effects. The Fluids and Combustion Facility (FCF) on the International Space Station (ISS) will support the study of fluid physics and combustion science in a long-duration microgravity environment. The Fluid Combustion Facility's design will permit both independent and remote control operations from the Telescience Support Center. The crew of the International Space Station will continue to insert and remove the experiment module, store and reload removable data storage and media data tapes, and reconfigure diagnostics on either side of the optics benches. Upon completion of the Fluids Combustion Facility, about ten experiments will be conducted within a ten-year period. Several different areas of fluid physics will be studied in the Fluids Combustion Facility. These areas include complex fluids, interfacial phenomena, dynamics and instabilities, and multiphase flows and phase change. Recently, emphasis has been placed in areas that relate directly to NASA missions including life support, power, propulsion, and thermal control systems. By 2006 or 2007, a Fluids Integrated Rack (FIR) and a Combustion Integrated Rack (CIR) will be installed inside the International Space Station. The Fluids Integrated Rack will contain all the hardware and software necessary to perform experiments in fluid physics. A wide range of experiments that meet the requirements of the international space station, including research from other specialties, will be considered. Experiments will be contained in subsystems such as the international standard payload rack, the active rack isolation system, the optics bench, environmental subsystem, electrical power control unit, the gas interface subsystem, and the command and data management subsystem. In conclusion, the Fluids and Combustion Facility will allow researchers to study fluid physics and combustion science in a long-duration microgravity environment. Additional information is

Intestinal fluid absorption in spontaneously hypertensive rats.

PubMed Central

Dorey, P G; King, J; Munday, K A; Parsons, B J; Poat, J A

1983-01-01

A comparison has been made of intestinal fluid absorption between male Okamoto spontaneously hypertensive rats (s.h.r.) and normotensive male Wistar controls. S.h.r. show enhanced fluid absorption both in hypertensive adults and in young s.h.r. before hypertension has developed. Several potential causes for increased fluid transport in s.h.r. were tested using pharmacological antagonists. It is unlikely that enhanced fluid absorption is due to high sympathetic nervous activity, the renin-angiotensin system or is secondary to hypertension. Intestine from s.h.r. have a high short-circuit current indicating a change in ion pump activity. These results are discussed in relation to the possible causes of increased fluid (ion) transport by the intestine of s.h.r. PMID:6361232

HPLC retention thermodynamics of grape and wine tannins.

PubMed

Barak, Jennifer A; Kennedy, James A

2013-05-08

The effect of grape and wine tannin structure on retention thermodynamics under reversed-phase high-performance liquid chromatography conditions on a polystyrene divinylbenzene column was investigated. On the basis of retention response to temperature, an alternative retention factor was developed to approximate the combined temperature response of the complex, unresolvable tannin mixture. This alternative retention factor was based upon relative tannin peak areas separated by an abrupt change in solvent gradient. Using this alternative retention factor, retention thermodynamics were calculated. Van't Hoff relationships of the natural log of the alternative retention factor against temperature followed Kirchoff's relationship. An inverse quadratic equation was fit to the data, and from this the thermodynamic parameters for tannin retention were calculated. All tannin fractions exhibited exothermic, spontaneous interaction, with enthalpy-entropy compensation observed. Normalizing for tannin size, distinct tannin compositional effects on thermodynamic parameters were observed. The results of this study indicate that HPLC can be valuable for measuring the thermodynamics of tannin interaction with a hydrophobic surface and provides a potentially valuable alternative to calorimetry. Furthermore, the information gathered may provide insight into understanding red wine astringency quality.

Soil Water Retention Curve

NASA Astrophysics Data System (ADS)

Johnson, L. E.; Kim, J.; Cifelli, R.; Chandra, C. V.

2016-12-01

Potential water retention, S, is one of parameters commonly used in hydrologic modeling for soil moisture accounting. Physically, S indicates total amount of water which can be stored in soil and is expressed in units of depth. S can be represented as a change of soil moisture content and in this context is commonly used to estimate direct runoff, especially in the Soil Conservation Service (SCS) curve number (CN) method. Generally, the lumped and the distributed hydrologic models can easily use the SCS-CN method to estimate direct runoff. Changes in potential water retention have been used in previous SCS-CN studies; however, these studies have focused on long-term hydrologic simulations where S is allowed to vary at the daily time scale. While useful for hydrologic events that span multiple days, the resolution is too coarse for short-term applications such as flash flood events where S may not recover its full potential. In this study, a new method for estimating a time-variable potential water retention at hourly time-scales is presented. The methodology is applied for the Napa River basin, California. The streamflow gage at St Helena, located in the upper reaches of the basin, is used as the control gage site to evaluate the model performance as it is has minimal influences by reservoirs and diversions. Rainfall events from 2011 to 2012 are used for estimating the event-based SCS CN to transfer to S. As a result, we have derived the potential water retention curve and it is classified into three sections depending on the relative change in S. The first is a negative slope section arising from the difference in the rate of moving water through the soil column, the second is a zero change section representing the initial recovery the potential water retention, and the third is a positive change section representing the full recovery of the potential water retention. Also, we found that the soil water moving has traffic jam within 24 hours after finished first

28 CFR 345.67 - Retention of benefits.

Code of Federal Regulations, 2010 CFR

2010-07-01

... INDUSTRIES (FPI) INMATE WORK PROGRAMS Inmate Pay and Benefits § 345.67 Retention of benefits. (a) Job retention. Ordinarily, when an inmate is absent from the job for a significant period of time, the SOI will... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Retention of benefits. 345.67 Section 345...

Novel word retention in bilingual and monolingual speakers

PubMed Central

Kan, Pui Fong; Sadagopan, Neeraja

2014-01-01

The goal of this research was to examine word retention in bilinguals and monolinguals. Long-term word retention is an essential part of vocabulary learning. Previous studies have documented that bilinguals outperform monolinguals in terms of retrieving newly-exposed words. Yet, little is known about whether or to what extent bilinguals are different from monolinguals in word retention. Participants were 30 English-speaking monolingual adults and 30 bilingual adults who speak Spanish as a home language and learned English as a second language during childhood. In a previous study (Kan et al., 2014), the participants were exposed to the target novel words in English, Spanish, and Cantonese. In this current study, word retention was measured a week after the fast mapping task. No exposures were given during the one-week interval. Results showed that bilinguals and monolinguals retain a similar number of words. However, participants produced more words in English than in either Spanish or Cantonese. Correlation analyses revealed that language knowledge plays a role in the relationships between fast mapping and word retention. Specifically, within- and across-language relationships between bilinguals' fast mapping and word retention were found in Spanish and English, by contrast, within-language relationships between monolinguals' fast mapping and word retention were found in English and across-language relationships between their fast mapping and word retention performance in English and Cantonese. Similarly, bilinguals differed from monolinguals in the relationships among the word retention scores in three languages. Significant correlations were found among bilinguals' retention scores. However, no such correlations were found among monolinguals' retention scores. The overall findings suggest that bilinguals' language experience and language knowledge most likely contribute to how they learn and retain new words. PMID:25324789

Novel word retention in bilingual and monolingual speakers.

PubMed

Kan, Pui Fong; Sadagopan, Neeraja

2014-01-01

The goal of this research was to examine word retention in bilinguals and monolinguals. Long-term word retention is an essential part of vocabulary learning. Previous studies have documented that bilinguals outperform monolinguals in terms of retrieving newly-exposed words. Yet, little is known about whether or to what extent bilinguals are different from monolinguals in word retention. Participants were 30 English-speaking monolingual adults and 30 bilingual adults who speak Spanish as a home language and learned English as a second language during childhood. In a previous study (Kan et al., 2014), the participants were exposed to the target novel words in English, Spanish, and Cantonese. In this current study, word retention was measured a week after the fast mapping task. No exposures were given during the one-week interval. Results showed that bilinguals and monolinguals retain a similar number of words. However, participants produced more words in English than in either Spanish or Cantonese. Correlation analyses revealed that language knowledge plays a role in the relationships between fast mapping and word retention. Specifically, within- and across-language relationships between bilinguals' fast mapping and word retention were found in Spanish and English, by contrast, within-language relationships between monolinguals' fast mapping and word retention were found in English and across-language relationships between their fast mapping and word retention performance in English and Cantonese. Similarly, bilinguals differed from monolinguals in the relationships among the word retention scores in three languages. Significant correlations were found among bilinguals' retention scores. However, no such correlations were found among monolinguals' retention scores. The overall findings suggest that bilinguals' language experience and language knowledge most likely contribute to how they learn and retain new words.

Urinary Retention

MedlinePlus

... urinary retention with • bladder drainage • urethral dilation • urethral stents • prostate medications • surgery The type and length of ... patient will receive sedation and regional anesthesia. Urethral Stents Another treatment for urethral stricture involves inserting an ...

Application of the self-generation effect to the learning of Blissymbols by persons presenting with a severe aphasia.

PubMed

Rajaram, Priya; Alant, Erna; Dada, Shakila

2012-06-01

This study investigated the application of the self-generation effect to enhance the recognition and retention of Blissymbols in persons with severe aphasia. A 2×2×3 factorial design of two treatment types (self-generation and non-generation) was used to teach two sets of Blissymbols. These were administered during 3 training days, between which were withdrawal periods of 1 day and 7 days. Recognition and retention probes were administered at intervals during the training. ANOVA analysis showed that the self-generation treatment produced no immediate recognition advantage; however, better retention of symbol recognition may have occurred over time. Hence, the potential application of the self-generation effect in enhancing the retention of Blissymbols in persons with severe aphasia may warrant further investigation.

Effect of beta-adrenergic blockade with carvedilol on cachexia in severe chronic heart failure: results from the COPERNICUS trial.

PubMed

Clark, Andrew L; Coats, Andrew J S; Krum, Henry; Katus, Hugo A; Mohacsi, Paul; Salekin, Damien; Schultz, Melissa K; Packer, Milton; Anker, Stefan D

2017-08-01

Cardiac cachexia frequently accompanies the progression of heart failure despite the use of effective therapies for left ventricular dysfunction. Activation of the sympathetic nervous system has been implicated in the pathogenesis of weight loss, but the effects of sympathetic antagonism on cachexia are not well defined. We prospectively evaluated changes in body weight in 2289 patients with heart failure who had dyspnoea at rest or on minimal exertion and a left ventricular ejection fraction <25%. Patients were randomly assigned (double-blind) to receive either placebo (n = 1133) or carvedilol (n = 1156) and were followed for the occurrence of major clinical events for up to 29 months (COPERNICUS trial). Patients were not enrolled if they had signs of clinically significant fluid retention due to heart failure. Patients in the carvedilol group were 33% less likely than patients in the placebo group to experience a further significant loss of weight (>6%) (95% confidence interval: 14-48%, P = 0.002) and were 37% more likely to experience a significant gain in weight (≥5%) (95% confidence interval: 12-66%, P = 0.002). Carvedilol's ability to prevent weight loss was most marked in patients with increased body mass index at baseline, whereas its ability to promote weight gain was most marked in patients with decreased body mass index at baseline. Increases in weight were not accompanied by evidence of fluid retention. Baseline values for body mass index and change in body weight were significant predictors of survival regardless of treatment. Carvedilol attenuated the development and promoted a partial reversal of cachexia in patients with severe chronic heart failure, supporting a role for prolonged sympathetic activation in the genesis of weight loss. © 2017 The Authors. Journal of Cachexia, Sarcopenia and Muscle published by John Wiley & Sons Ltd on behalf of the Society on Sarcopenia, Cachexia and Wasting Disorders.

Transient urinary retention and chronic neuropathic pain associated with genital herpes simplex virus infection.

PubMed

Haanpää, Maija; Paavonen, Jorma

2004-10-01

Genital herpes (GH) causes genital ulcer disease, severe transient pain, and often paresthesias. Whether or not GH can cause urinary retention or chronic neuropathic pain is not well known. We present two immunocompetent patients with GH associated with neuropathic symptoms. We also review the literature on GH and associated neurologic problems. Patient 1 had primary herpes simplex virus (HSV)-2 infection with transient urinary retention and chronic bilateral neuropathic pain in the sacral area. Patient 2 had recurrent HSV-1 associated with unitaleral chronic neuropathic pain in the sacral area. Although transient urinary retention associated with GH is not uncommon, chronic neuropathic pain has not been reported previously. Our cases show that chronic neuropathic pain, that is "pain initiated or caused by a primary lesion or dysfunction in the nervous system," can follow genital HSV infection.

Strategies for improving employee retention.

PubMed

Verlander, Edward G; Evans, Martin R

2007-03-28

This article proposes a solution to the perennial problem of talent retention in the clinical laboratory. It includes the presentation of 12 strategies that may be used to significantly improve institutional identity formation and establishment of the psychological contract that employees form with laboratory management. Identity formation and psychological contracting are deemed as essential in helping reduce employee turnover and increase retention. The 12 conversational strategies may be used as a set of best practices for all employees, but most importantly for new employees, and should be implemented at the critical moment when employees first join the laboratory. This time is referred to as "retention on-boarding"--the period of induction and laboratory orientation. Retention on-boarding involves a dialogue between employees and management that is focused on the psychological, practical, cultural, and political dimensions of the laboratory. It is placed in the context of the modern clinical laboratory, which is faced with employing and managing Generation X knowledge workers. Specific topics and broad content areas of those conversations are outlined.

Computer simulation of the effect of dDAVP with saline loading on fluid balance after 24-hour head-down tilt

NASA Technical Reports Server (NTRS)

Srinivasan, R. S.; Simanonok, K. E.; Charles, J. B.

1994-01-01

Fluid loading (FL) before Shuttle reentry is a countermeasure currently in use by NASA to improve the orthostatic tolerance of astronauts during reentry and postflight. The fluid load consists of water and salt tablets equivalent to 32 oz (946 ml) of isotonic saline. However, the effectiveness of this countermeasure has been observed to decrease with the duration of spaceflight. The countermeasure's effectiveness may be improved by enhancing fluid retention using analogs of vasopressin such as lypressin (LVP) and desmopressin (dDAVP). In a computer simulation study reported previously, we attempted to assess the improvement in fluid retention obtained by the use of LVP administered before FL. The present study is concerned with the use of dDAVP. In a recent 24-hour, 6 degree head-down tilt (HDT) study involving seven men, dDAVP was found to improve orthostatic tolerance as assessed by both lower body negative pressure (LBNP) and stand tests. The treatment restored Luft's cumulative stress index (cumulative product of magnitude and duration of LBNP) to nearly pre-bedrest level. The heart rate was lower and stroke volume was marginally higher at the same LBNP levels with administration of dDAVP compared to placebo. Lower heart rates were also observed with dDAVP during stand test, despite the lower level of cardiovascular stress. These improvements were seen with only a small but significant increase in plasma volume of approximately 3 percent. This paper presents a computer simulation analysis of some of the results of this HDT study.

Fluid Sources at the Panasqueira Tungsten-Vein Deposit

NASA Astrophysics Data System (ADS)

Lecumberri-Sanchez, P.; Heinrich, C. A.; Wälle, M.; Codeço, M.; Weis, P.; Pinto, F.; Vieira, R.

2017-12-01

Panasqueira is a world-class tungsten-vein deposit. Several paragenetic stages have been proposed (Polya et al., 2000) including two pre-ore stages (crack-seal quartz-seam, and muscovite selvages) and four ore stages (main oxide-silicate stage, main sulfide stage, pyrrhotite alteration stage, and late carbonate stage). In this study, compositions of the mineralizing fluids at Panasqueira have been determined by a combination of detailed petrography, microthermometric measurements and LA-ICPMS analyses. We have characterized the fluids related to several mineralizing stages and determined the information they provide about the fluid sources in this system. Three fluid generations recorded in pseudosecondary to secondary fluid inclusions have been identified at Panasqueira. The first fluid generation identified consists of CO2-bearing fluid inclusions with homogenization temperatures ranging between 260 and 320 °C and salinities between 5 and 8 eq wt % NaCl. Petrographic constraints indicate that this first generation (1) is paragenetically related to the main oxide-silicate stage. Two lower-temperature CO2-absent fluid generations (2a and 2b) have been identified and are represented by secondary fluid inclusions postdating the main oxide-silicate stage. This stage was likely trapped under high pressures and lithostatic conditions (Jacques and Pascal, 2017). Generation (2a) consists of high-salinity (20-30 eq wt % NaCl) fluids with homogenization temperatures ranging between 180°C and 250°C. Generation (2b) consists of low-salinity (<2 wt %) low homogenization temperature (100-150°C) fluid inclusions. Conclusive petrographic evidence of the relationship between these two late-stage fluid generations and specific late mineral stages are scarce. However, fluid compositions suggests that generation (2a) is related to the main sulfide stage and generation (2b) is related to the late carbonate stage. The PTX evolution of fluids at Panasqueira indicate a transition

Fluid overload in the ICU: evaluation and management.

PubMed

Claure-Del Granado, Rolando; Mehta, Ravindra L

2016-08-02

Fluid overload is frequently found in acute kidney injury patients in critical care units. Recent studies have shown the relationship of fluid overload with adverse outcomes; hence, manage and optimization of fluid balance becomes a central component of the management of critically ill patients. In critically ill patients, in order to restore cardiac output, systemic blood pressure and renal perfusion an adequate fluid resuscitation is essential. Achieving an appropriate level of volume management requires knowledge of the underlying pathophysiology, evaluation of volume status, and selection of appropriate solution for volume repletion, and maintenance and modulation of the tissue perfusion. Numerous recent studies have established a correlation between fluid overload and mortality in critically ill patients. Fluid overload recognition and assessment requires an accurate documentation of intakes and outputs; yet, there is a wide difference in how it is evaluated, reviewed and utilized. Accurate volume status evaluation is essential for appropriate therapy since errors of volume evaluation can result in either in lack of essential treatment or unnecessary fluid administration, and both scenarios are associated with increased mortality. There are several methods to evaluate fluid status; however, most of the tests currently used are fairly inaccurate. Diuretics, especially loop diuretics, remain a valid therapeutic alternative. Fluid overload refractory to medical therapy requires the application of extracorporeal therapies. In critically ill patients, fluid overload is related to increased mortality and also lead to several complications like pulmonary edema, cardiac failure, delayed wound healing, tissue breakdown, and impaired bowel function. Therefore, the evaluation of volume status is crucial in the early management of critically ill patients. Diuretics are frequently used as an initial therapy; however, due to their limited effectiveness the use of continuous

phosphorus retention data and metadata

EPA Pesticide Factsheets

phosphorus retention in wetlands data and metadataThis dataset is associated with the following publication:Lane , C., and B. Autrey. Phosphorus retention of forested and emergent marsh depressional wetlands in differing land uses in Florida, USA. Wetlands Ecology and Management. Springer Science and Business Media B.V;Formerly Kluwer Academic Publishers B.V., GERMANY, 24(1): 45-60, (2016).

Considering Student Retention as a Complex System: A Possible Way forward for Enhancing Student Retention

ERIC Educational Resources Information Center

Forsman, Jonas; van den Bogaard, Maartje; Linder, Cedric; Fraser, Duncan

2015-01-01

This study uses multilayer minimum spanning tree analysis to develop a model for student retention from a complex system perspective, using data obtained from first-year engineering students at a large well-regarded institution in the European Union. The results show that the elements of the system of student retention are related to one another…

Employee retention: a customer service approach.

PubMed

Gerson, Richard F

2002-01-01

Employee retention is a huge problem. There are staff shortages in radiology because not enough people are entering the profession; too many people are leaving the profession for retirement, higher-paying jobs or jobs with less stress; and there are not enough opportunities for career advancement. Staff shortages are exacerbated by difficulty in retaining people who enter the profession. While much work has been focused on recruitment and getting more people "in the front door," I suggest that the bulk of future efforts be focused on employee retention and "closing the back door." Employee retention must be an ongoing process, not a program. Approaches to employee retention that focus on external things, i.e., things that the company can do to or for the employee, generally are not successful. The truth is that employee retention processes must focus on what the employee gets out of the job. The process must be a benefits-based approach that helps employees answer the question, "What's in it for me?" The retention processes must be ongoing and integrated into the daily culture of the company. The best way to keep your employees is to treat them like customers. Customer service works for external customers. We treat them nicely. We work to satisfy them. We help them achieve their goals. Why not do the same for our employees? If positive customer service policies and practices can satisfy and keep external customers, why not adapt these policies and practices for employees? And, there is a service/satisfaction link between employee retention and higher levels of customer satisfaction. Customers prefer dealing with the same employees over and over again. Employee turnover destroys a customer's confidence in the company. Just like a customer does not want to have to "train and educate" a new provider, they do not want to do the same for your "revolving door" employees. So, the key is to keep employees so they in turn will help you keep your customers. Because the

Hydrogen retention in lithium and lithium oxide films

NASA Astrophysics Data System (ADS)

Buzi, L.; Yang, Y.; Domínguez-Gutiérrez, F. J.; Nelson, A. O.; Hofman, M.; Krstić, P. S.; Kaita, R.; Koel, B. E.

2018-04-01

Pure lithium (Li) surfaces are difficult to maintain in fusion devices due to rapid oxide formation, therefore, parameterizing and understanding the mechanisms of hydrogen (H, D) retention in lithium oxide (Li2O) in addition to pure Li is crucial for Li plasma-facing material applications. To compare H retention in Li and Li2O films, measurements were made as a function of surface temperature (90-520 K) under ultrahigh vacuum (UHV) conditions using temperature programmed desorption (TPD). In both cases, the total retention dropped with surface temperature, from 95% at 90 K to 35% at 520 K Li2O films retained H in similar amounts as pure Li. Molecular Dynamics (MD) modeling was used to elucidate the mechanisms of H retention, and results were consistent with experiments in terms of both retention fraction and the drop of retention with temperature.

A Chlorine-Centric Perspective on Fluid-Mediated Processes at Convergent Plate Boundaries

NASA Astrophysics Data System (ADS)

Selverstone, J.

2014-12-01

The release and migration of metamorphic fluids from subducting slabs into overlying mantle is widely recognized as a major mechanism in producing arc geochemical signatures and returning fluid-mobile elements to earth's crust and surface environments. Although the magnitudes of many geochemical fluxes are well constrained, the processes whereby mass transfer occurs in different portions of the subduction system are less well known. Chlorine stable isotopes provide a new perspective on some of these processes: Cl is hydrophilic, but decarbonation reactions favor Cl retention in minerals. Cl also shows less isotopic fractionation than other fluid-sensitive systems and may thus preserve evidence of specific fluid sources and/or fluid mixing events. Detailed studies of sedimentary sequences show that individual beds are isotopically homogeneous but large heterogeneities in δ37Cl exist across beds on a cm to m scale and vary as a function of depositional environment. Compositionally correlative medium-, high-, and ultrahigh-pressure metamorphic sequences in the Alps record decreases of 30-50% in Cl contents in the earliest stages of metamorphism, but little change thereafter. No statistically significant change in isotopic composition occurs during prograde metamorphism of individual horizons, and the same large degree of isotopic heterogeneity (up to 6‰) persists throughout the prograde devolatilization history of the rocks. Likewise, analysis of HP/UHP serpentinites and altered oceanic crust show that heterogeneous protolith compositions are preserved during transport to sub-arc depths, despite large-scale devolatilization. However, upward transport of rocks within the subduction channel results in highly localized interaction with isotopically distinct, Cl-bearing fluid packets. Overlying forearc wedge rocks also record heterogeneous and channelized interaction with distinct fluid components with different δ37Cl. Within-layer fluid compartmentalization during

Critical asymmetry in renormalization group theory for fluids.

PubMed

Zhao, Wei; Wu, Liang; Wang, Long; Li, Liyan; Cai, Jun

2013-06-21

The renormalization-group (RG) approaches for fluids are employed to investigate critical asymmetry of vapour-liquid equilibrium (VLE) of fluids. Three different approaches based on RG theory for fluids are reviewed and compared. RG approaches are applied to various fluid systems: hard-core square-well fluids of variable ranges, hard-core Yukawa fluids, and square-well dimer fluids and modelling VLE of n-alkane molecules. Phase diagrams of simple model fluids and alkanes described by RG approaches are analyzed to assess the capability of describing the VLE critical asymmetry which is suggested in complete scaling theory. Results of thermodynamic properties obtained by RG theory for fluids agree with the simulation and experimental data. Coexistence diameters, which are smaller than the critical densities, are found in the RG descriptions of critical asymmetries of several fluids. Our calculation and analysis show that the approach coupling local free energy with White's RG iteration which aims to incorporate density fluctuations into free energy is not adequate for VLE critical asymmetry due to the inadequate order parameter and the local free energy functional used in the partition function.

Transport and Retention of Carboxymethylcellulose-Modified Carbon Nanotube-Magnetite Nanohybrids in Water-Saturated Porous Media

NASA Astrophysics Data System (ADS)

Wang, D.; Su, C.

2017-12-01

Carbon-metal oxide nanohybrids (NHs) are increasingly recognized as the next-generation, promising group of nanomaterials for solving emerging environmental issues and challenges. This research, for the first time, systematically explored the transport and retention of the multifunctional carbon nanotube-magnetite (CNT-Fe3O4) NHs in water-saturated porous media under environmentally relevant physicochemical conditions. An environment-benign macromolecule, carboxymethylcellulose (CMC), was employed to stabilize the NHs. Classical Derjaguin-Landau-Verwey-Overbeek (DLVO) theory and colloid transport model were used to describe the transport and retention of the NHs. Our results showed that transport of the magnetic CNT-Fe3O4 NHs was lower than that of the parent CNT due to greater aggregation (induced by magnetic attraction) during transport. The DLVO theory well-interpreted the NHs' transport; and secondary minimum played dominant roles in NHs' retention. A novel transport feature, an initial low and following sharp peaks occurred frequently in the NHs' breakthrough curves; and the magnitude and location of both transport peaks varied with different experimental conditions due to the interplay between variability of the fluid viscosity and aggregation-dispersion nature of the NHs. Very promisingly, the estimated maximum transport distance of NHs using the Tufenkji-Elimelech equation ranged between 0.38-46 m, supporting the feasibility of employing the magnetically recyclable CNT-Fe3O4 NHs for in-situ nanoremediation of contaminated soils, sediment aquifers, and groundwater.

Diagnostic imaging of small amounts of pleural fluid: pleural effusion vs. physiologic pleural fluid.

PubMed

Kocijancic, Igor

2007-12-01

The aim of this article is to present an overview of our 10 years clinical research work and early clinical experience with small pleural effusions. Small amounts of pleural fluid are severely difficult to identify with imaging methods (chest x-rays and ultrasound). Nevertheless, it may be an important finding, sometimes leading to a definitive diagnosis of pleural carcinomatosis, infection or other pathologic condition. Chest x-rays were used for many years for the diagnosis of small pleural effusions. Lateral decubitus chest radiographs represented a gold standard for imaging of small amounts of plural fluid for more than 80 years. In the last two decades, ultrasonography of pleural space became a leading real-time method for demonstrating small pleural effusions. Furthermore, the advent of sonographic technology actually enables detection of physiologic pleural fluid in some otherwise healthy individuals. In conclusion, new definitions of the key terms in the field of diagnostic imaging of small amounts of pleural fluid seem to be justified. We suggest that the term pleural fluid should determine physiologic pleural space condition while the term pleural effusion should only be used in the cases of pleural involvement or pleural illness.

Water retention curve for hydrate-bearing sediments

NASA Astrophysics Data System (ADS)

Dai, Sheng; Santamarina, J. Carlos

2013-11-01

water retention curve plays a central role in numerical algorithms that model hydrate dissociation in sediments. The determination of the water retention curve for hydrate-bearing sediments faces experimental difficulties, and most studies assume constant water retention curves regardless of hydrate saturation. This study employs network model simulation to investigate the water retention curve for hydrate-bearing sediments. Results show that (1) hydrate in pores shifts the curve to higher capillary pressures and the air entry pressure increases as a power function of hydrate saturation; (2) the air entry pressure is lower in sediments with patchy rather than distributed hydrate, with higher pore size variation and pore connectivity or with lower specimen slenderness along the flow direction; and (3) smaller specimens render higher variance in computed water retention curves, especially at high water saturation Sw > 0.7. Results are relevant to other sediment pore processes such as bioclogging and mineral precipitation.

A Cost Benefit Analysis Between the Current Naval Officer Retention Bonus Plan and the Enlisted Retention Bonus Plan

DTIC Science & Technology

2016-06-01

that personnel targeted for retention had a direct ability to affect the success of the transaction and company. High potential, job function, job level...and job title rounded out the top five reasons personnel were targeted for retention . In brief, this study found that slightly more than half of...lower income may value the job security provided by service in the military, thus making retention in the military a more attractive option. 4

Fluid, energy and nutrient recovery via ad libitum intake of different fluids and food.

PubMed

Campagnolo, Nadia; Iudakhina, Elizaveta; Irwin, Christopher; Schubert, Matthew; Cox, Gregory R; Leveritt, Michael; Desbrow, Ben

2017-03-15

This study compared the effects of ad libitum consumption of different beverages and foods on fluid retention and nutrient intake following exercise. Ten endurance trained males (mean±SD; Age=25.3±4.9years, VO 2 max=63.0±7.2mL·kg·min -1 ) performed four trials employing a counterbalanced, crossover design. Following 60min of exercise (matched for energy expenditure and fluid loss) participants consumed either water (W1 and W2), a sports drink (Powerade® (P)) or a milk-based liquid meal supplement (Sustagen Sport® (SS)) over a four hour recovery period. Additionally, participants had access to snack foods on two occasions within the first 2h of recovery on all trials. All beverages and food were consumed ad libitum. Total nutrient intake, urine volume, USG, body weight as well as subjective measures of gastrointestinal tolerance and thirst were obtained hourly. Plasma osmolality was measured pre, post, 1 and 4h after exercise. Total fluid volume ingested from food and beverages in W1 (2.28±0.42L) and P (2.82±0.80L) trials were significantly greater than SS (1.94±0.54L). Total urine output was not different between trials (W1=644±202mL, W2=602±352mL, P=879±751mL, SS=466±129mL). No significant differences in net body weight change was observed between trials (W1=0.01±0.28kg, W2=0.08±0.30kg, P=-0.02±0.24kg, SS=-0.05±0.24kg). Total energy intake was higher on P (10,179±1484kJ) and SS (10,577±2210kJ) compared to both water trials (W1=7826±888kJ, W2=7578±1112kJ). With the co-ingestion of food, fluid restoration following exercise is tightly regulated and not influenced by the choice of either water, a carbohydrate-electrolyte (sports drink) or a milk-based beverage. Copyright © 2017 Elsevier Inc. All rights reserved.

β-Liddle mutation of the epithelial sodium channel increases alveolar fluid clearance and reduces the severity of hydrostatic pulmonary oedema in mice

PubMed Central

Randrianarison, Nadia; Escoubet, Brigitte; Ferreira, Chrystophe; Fontayne, Alexandre; Fowler-Jaeger, Nicole; Clerici, Christine; Hummler, Edith; Rossier, Bernard C; Planès, Carole

2007-01-01

Transepithelial sodium transport via alveolar epithelial Na+ channels and Na+,K+-ATPase constitutes the driving force for removal of alveolar oedema fluid. Decreased activity of the amiloride-sensitive epithelial Na+ channel (ENaC) in the apical membrane of alveolar epithelial cells impairs sodium-driven alveolar fluid clearance (AFC) and predisposes to pulmonary oedema. We hypothesized that hyperactivity of ENaC in the distal lung could improve AFC and facilitate the resolution of pulmonary oedema. AFC and lung fluid balance were studied at baseline and under conditions of hydrostatic pulmonary oedema in the β-Liddle (L) mouse strain harbouring a gain-of-function mutation (R566stop) within the Scnn1b gene. As compared with wild-type (+/+), baseline AFC was increased by 2- and 3-fold in heterozygous (+/L) and homozygous mutated (L/L) mice, respectively, mainly due to increased amiloride-sensitive AFC. The β2-agonist terbutaline stimulated AFC in +/+ and +/L mice, but not in L/L mice. Acute volume overload induced by saline infusion (40% of body weight over 2 h) significantly increased extravascular (i.e. interstitial and alveolar) lung water as assessed by the bloodless wet-to-dry lung weight ratio in +/+ and L/L mice, as compared with baseline. However, the increase was significantly larger in +/+ than in L/L groups (P= 0.01). Volume overload also increased the volume of the alveolar epithelial lining fluid in +/+ mice, indicating the presence of alveolar oedema, but not in L/L mice. Cardiac function as evaluated by echocardiography was comparable in both groups. These data show that constitutive ENaC activation improved sodium-driven AFC in the mouse lung, and attenuated the severity of hydrostatic pulmonary oedema. PMID:17430990

5 CFR 950.604 - Records retention.

Code of Federal Regulations, 2011 CFR

2011-01-01

... VOLUNTARY ORGANIZATIONS Miscellaneous Provisions § 950.604 Records retention. Federations, PCFOs and other... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Records retention. 950.604 Section 950.604 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS...

5 CFR 950.604 - Records retention.

Code of Federal Regulations, 2013 CFR

2013-01-01

... VOLUNTARY ORGANIZATIONS Miscellaneous Provisions § 950.604 Records retention. Federations, PCFOs and other... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false Records retention. 950.604 Section 950.604 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS...

5 CFR 950.604 - Records retention.

Code of Federal Regulations, 2014 CFR

2014-01-01

... VOLUNTARY ORGANIZATIONS Miscellaneous Provisions § 950.604 Records retention. Federations, PCFOs and other... 5 Administrative Personnel 2 2014-01-01 2014-01-01 false Records retention. 950.604 Section 950.604 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS...

5 CFR 950.604 - Records retention.

Code of Federal Regulations, 2012 CFR

2012-01-01

... VOLUNTARY ORGANIZATIONS Miscellaneous Provisions § 950.604 Records retention. Federations, PCFOs and other... 5 Administrative Personnel 2 2012-01-01 2012-01-01 false Records retention. 950.604 Section 950.604 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS...

5 CFR 950.604 - Records retention.

Code of Federal Regulations, 2010 CFR

2010-01-01

... VOLUNTARY ORGANIZATIONS Miscellaneous Provisions § 950.604 Records retention. Federations, PCFOs and other... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Records retention. 950.604 Section 950.604 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS...

A successful Minority Retention Project.

PubMed

Gardner, Janelle D

2005-12-01

Racial and ethnic minorities are underrepresented in the nursing profession. The high attrition rate of minority students from nursing schools contributes to this problem. Academic leaders are calling for change in nursing education and asking educators to work diligently to retain minority students. This article describes a Minority Retention Project that included interventions designed to enhance the integration of minority students into a supportive learning environment, assist them in using the available resources, and help them feel connected and supported by their peers and faculty. At the end of the first year of the project, the nursing school experienced 100% retention of minority nursing students. Increasing the retention and graduation of minority nursing students supports the continued effort to provide culturally competent health care.

Round window electrode insertion potentiates retention in the scala tympani.

PubMed

Connor, Stephen E J; Holland, N Julian; Agger, Andreas; Leong, Annabelle C; Varghese, Re Ajay; Jiang, Dan; Fitzgerald O'Connor, Alec

2012-09-01

The round window membrane (RWM)-intentioned approach is superior to the traditional bony cochleostomy (BC) approach in obtaining electrode placement within the scala tympani (ST). Cochlear implant outcome is influenced by several factors, including optimal placement and retention of the electrode array within the ST. The present study aimed to assess whether the RWM route is superior to a traditional BC for placement and retention of the electrode array in the ST. This was a prospective consecutive non-randomized comparison study. All patients were implanted with the Advanced Bionics 1J electrode array. The RWM approach (n = 32) was compared with a traditional BC group (n = 33). The outcome measure was the electrode position as judged within the scalar chambers at four points along the basal turn using postoperative computed tomography (CT). When the mean position scores were compared, the RWM-intentioned group had significantly more electrodes directed towards the ST compartment than the BC group (p < 0.001). The RWM electrodes achieved 94% ST retention compared with 64% for the BC group (p < 0.05). All electrodes stayed in the ST in the RWM group, whereas in the BC group 9% crossed from the ST to the scala vestibuli.

Newly Licensed RN Retention: Hospital and Nurse Characteristics.

PubMed

Blegen, Mary A; Spector, Nancy; Lynn, Mary R; Barnsteiner, Jane; Ulrich, Beth T

2017-10-01

The aims of this study were to examine the relationship between 1-year retention of newly licensed RNs (NLRNs) employed in hospitals and personal and hospital characteristics, and determine which characteristics had the most influence. A secondary analysis of data collected in a study of transition to practice was used to describe the retention of 1464 NLRNs employed by 97 hospitals in 3 states. Hospitals varied in size, location (urban and rural), Magnet® designation, and university affiliation. The NLRNs also varied in education, age, race, gender, and experience. The overall retention rate at 1 year was 83%. Retention of NLRNs was higher in urban areas and in Magnet hospitals. The only personal characteristic that affected retention was age, with younger nurses more likely to stay. Hospital characteristics had a larger effect on NLRN retention than personal characteristics. Hospitals in rural areas have a particular challenge in retaining NLRNs.

Hydrogen retention in lithium and lithium oxide films

DOE PAGES

Buzi, L.; Yang, Y.; Dominguez-Gutierrez, F. J.; ...

2018-02-09

Pure lithium (Li) surfaces are difficult to maintain in fusion devices due to rapid oxide formation, therefore, parameterizing and understanding the mechanisms of hydrogen (H, D) retention in lithium oxide (Li 2O) in addition to pure Li is crucial for Li plasma-facing material applications. To compare H retention in Li and Li 2O films, measurements were made as a function of surface temperature (90–520 K) under ultrahigh vacuum (UHV) conditions using temperature programmed desorption (TPD). In both cases, the total retention dropped with surface temperature, from 95% at 90 K to 35% at 520 K Li 2O films retained Hmore » in similar amounts as pure Li. Finally, Molecular Dynamics (MD) modeling was used to elucidate the mechanisms of H retention, and results were consistent with experiments in terms of both retention fraction and the drop of retention with temperature.« less

Hydrogen retention in lithium and lithium oxide films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Buzi, L.; Yang, Y.; Dominguez-Gutierrez, F. J.

Pure lithium (Li) surfaces are difficult to maintain in fusion devices due to rapid oxide formation, therefore, parameterizing and understanding the mechanisms of hydrogen (H, D) retention in lithium oxide (Li 2O) in addition to pure Li is crucial for Li plasma-facing material applications. To compare H retention in Li and Li 2O films, measurements were made as a function of surface temperature (90–520 K) under ultrahigh vacuum (UHV) conditions using temperature programmed desorption (TPD). In both cases, the total retention dropped with surface temperature, from 95% at 90 K to 35% at 520 K Li 2O films retained Hmore » in similar amounts as pure Li. Finally, Molecular Dynamics (MD) modeling was used to elucidate the mechanisms of H retention, and results were consistent with experiments in terms of both retention fraction and the drop of retention with temperature.« less

Fluid therapy and the hypovolemic microcirculation.

PubMed

Gruartmoner, G; Mesquida, J; Ince, Can

2015-08-01

In shock states, optimizing intravascular volume is crucial to promote an adequate oxygen delivery to the tissues. Our current practice in fluid management pivots on the Frank-Starling law of the heart, and the effects of fluids are measured according to the induced changes on stroke volume. The purpose of this review is to evaluate the boundaries of current macrohemodynamic approach to fluid administration, and to introduce the microcirculatory integration as a fundamental part of tissue perfusion monitoring. Macrocirculatory changes induced by volume expansion are not always coupled to proportional changes in microcirculatory perfusion. Loss of hemodynamic coherence limits the value of guiding fluid therapy according to macrohemodynamics, and highlights the importance of evaluating the ultimate target of volume administration, the microcirculation. Current approach to intravascular volume optimization is made from a macrohemodynamic perspective. However, several situations wherein macrocirculatory and microcirculatory coherence is lost have been described. Future clinical trials should explore the usefulness of integrating the microcirculatory evaluation in fluid optimization.

Predictors of retention in community-based methadone maintenance treatment program in Pearl River Delta, China

PubMed Central

2013-01-01

Background The aims were to identify predictors of treatment retention in methadone maintenance treatment (MMT) clinics in Pearl River Delta, China. Methods Retrospective longitudinal study. Participants: 6 MMT clinics in rural and urban area were selected. Statistical analysis: Stratified random sampling was employed, and the data were analyzed using Kaplan-Meier survival curves and life table method. Protective or risk factors were explored using Cox’s proportional hazards model. Independent variables were enrolled in univariate analysis and among which significant variables were analyzed by multivariate analysis. Results A total of 2728 patients were enrolled. The median of the retention duration was 13.63 months, and the cumulative retention rates at 1,2,3 years were 53.0%, 35.0%, 20.0%, respectively. Multivariate Cox analysis showed: age, relationship with family, live on support from family or friends, income, considering treatment cost suitable, considering treatment open time suitable, addiction severity (daily expense for drug), communication with former drug taking peer, living in rural area, daily treatment dosage, sharing needles, re-admission and history of being arrested were predictors for MMT retention. Conclusions MMT retention rate in Guangdong was low and treatment skills and quality should be improved. Meanwhile, participation of family and society should be encouraged. PMID:23497263

Evaluation of Data Retention Characteristics for Ferroelectric Random Access Memories (FRAMs)

NASA Technical Reports Server (NTRS)

Sharma, Ashok K.; Teverovsky, Alexander

2001-01-01

Data retention and fatigue characteristics of 64 Kb lead zirconate titanate (PZT)-based Ferroelectric Random Access Memories (FRAMs) microcircuits manufactured by Ramtron were examined over temperature range from -85 C to +310 C for ceramic packaged parts and from -85 C to +175 C for plastic parts, during retention periods up to several thousand hours. Intrinsic failures, which were caused by a thermal degradation of the ferroelectric cells, occurred in ceramic parts after tens or hundreds hours of aging at temperatures above 200 C. The activation energy of the retention test failures was 1.05 eV and the extrapolated mean-time-to-failure (MTTF) at room temperature was estimated to be more than 280 years. Multiple write-read cycling (up to 3x10(exp 7)) during the fatigue testing of plastic and ceramic parts did not result in any parametric or functional failures. However, operational currents linearly decreased with the logarithm of number of cycles thus indicating fatigue process in PZT films. Plastic parts, that had more recent date code as compared to ceramic parts, appeared to be using die with improved process technology and showed significantly smaller changes in operational currents and data access times.

Predictors of Calcium Retention in Adolescent Boys

PubMed Central

Hill, Kathleen M.; Braun, Michelle; Kern, Mark; Martin, Berdine R.; Navalta, James W.; Sedlock, Darlene A.; McCabe, Linda; McCabe, George P.; Peacock, Munro; Weaver, Connie M.

2008-01-01

Context: The relationship between calcium (Ca) intake and Ca retention in adolescent boys was recently reported. Objective: This study evaluated the influence of Ca intake, serum hormone levels, biomarkers of bone metabolism, habitual physical activity, habitual Ca intake, and physical fitness on Ca retention in the same sample. Design: This study was a randomized, cross-over design that consisted of two 3-wk metabolic balance periods. Setting: The study took place on a university campus as a summer camp. Patients or Other Participants: A total of 31 American white boys (13–15 yr) participated in the study. Interventions: Each subject consumed a controlled diet with one of five high-low Ca intake pairs that ranged from 670-2003 mg/d, which was manipulated utilizing a fortified beverage. Main Outcome Measures: Ca retention was determined by Ca intake minus urinary and fecal Ca excretion during each balance period. Results: Ca intake explained 21.7% of the variability in Ca retention, and serum IGF-I concentration explained an additional 11.5%. Other serum hormone levels did not significantly add to the model. Biomarkers of bone metabolism, habitual physical activity, habitual Ca intake, and physical fitness were not significant predictors of Ca retention in adolescent boys. Conclusions: IGF-I, a regulator of growth during puberty, is an important predictor of Ca retention in adolescent boys. However, dietary Ca intake is an even greater predictor of Ca retention during this period of growth. PMID:18840643

METHOD FOR THE SUPERCRITICAL FLUID EXTRACTION OF SOILS/SEDIMENTS

EPA Science Inventory

Supercritical fluid extraction has been publicized as an extraction method which has several advantages over conventional methods, and it is expected to result in substantial cost and labor savings. This study was designed to evaluate the feasibility of using supercritical fluid ...

Retention behavior of isomeric polycyclic aromatic sulfur heterocycles in gas chromatography on stationary phases of different selectivity

PubMed Central

Wilson, Walter B.; Sander, Lane C.; Oña-Ruales, Jorge O.; Mössner, Stephanie G.; Sidisky, Leonard M.; Lee, Milton L.; Wise, Stephen A.

2017-01-01

Retention indices for 48 polycyclic aromatic sulfur heterocycles (PASHs) were determined using gas chromatography with three different stationary phases: a 50% phenyl phase, a 50% liquid crystalline dimethylpolysiloxane (LC-DMPS) phase, and an ionic liquid (IL) phase. Correlations between the retention behavior on the three stationary phases and PASH geometry (L/B and T, i.e., length-to-breadth ratio and thickness, respectively) were investigated for the following four isomer sets: (1) 4 three-ring molecular mass (MM) 184 Da PASHs, (2) 13 four-ring MM 234 Da PASHs, (3) 10 five-ring MM 258 Da PASHs, and (4) 20 five-ring MM 284 Da PASHs. Correlation coefficients for retention on the 50% LC-DMPS vs L/B ranged from r = 0.50 (MM 284 Da) to r = 0.77 (MM 234 Da). Correlation coefficients for retention on the IL phase vs L/B ranged from r = 0.31 (MM 234 Da) to r = 0.54 (MM 284 Da). Correlation coefficients for retention on the 50% phenyl vs L/B ranged from r = 0.14 (MM 258 Da) to r = 0.59 (MM 284 Da). Several correlation trends are discussed in detail for the retention behavior of PASH on the three stationary phases. PMID:28089272

Retention behavior of isomeric polycyclic aromatic sulfur heterocycles in gas chromatography on stationary phases of different selectivity.

PubMed

Wilson, Walter B; Sander, Lane C; Oña-Ruales, Jorge O; Mössner, Stephanie G; Sidisky, Leonard M; Lee, Milton L; Wise, Stephen A

2017-02-17

Retention indices for 48 polycyclic aromatic sulfur heterocycles (PASHs) were determined using gas chromatography with three different stationary phases: a 50% phenyl phase, a 50% liquid crystalline dimethylpolysiloxane (LC-DMPS) phase, and an ionic liquid (IL) phase. Correlations between the retention behavior on the three stationary phases and PASH geometry (L/B and T, i.e., length-to-breadth ratio and thickness, respectively) were investigated for the following four isomer sets: (1) 4 three-ring molecular mass (MM) 184Da PASHs, (2) 13 four-ring MM 234Da PASHs, (3) 10 five-ring MM 258Da PASHs, and (4) 20 five-ring MM 284Da PASHs. Correlation coefficients for retention on the 50% LC-DMPS vs L/B ranged from r=0.50 (MM 284Da) to r=0.77 (MM 234Da). Correlation coefficients for retention on the IL phase vs L/B ranged from r=0.31 (MM 234Da) to r=0.54 (MM 284Da). Correlation coefficients for retention on the 50% phenyl vs L/B ranged from r=0.14 (MM 258Da) to r=0.59 (MM 284Da). Several correlation trends are discussed in detail for the retention behavior of PASH on the three stationary phases. Published by Elsevier B.V.

Short-term effects of grade retention on the growth rate of Woodcock-Johnson III broad math and reading scores.

PubMed

Wu, Wei; West, Stephen G; Hughes, Jan N

2008-02-01

We investigated the effects of grade retention in first grade on the growth of the Woodcock-Johnson broad mathematics and reading scores over three years using linear growth curve modeling on an academically at-risk sample. A large sample (n=784) of first grade children who were at risk for retention was initially identified based on low literacy scores. Scores representing propensity for retention were constructed based on 72 variables collected in comprehensive baseline testing in first grade. We closely matched 97 pairs of retained and promoted children based on their propensity scores using optimal matching procedures. This procedure adjusted for baseline differences between the retained and promoted children. We found that grade retention decreased the growth rate of mathematical skills but had no significant effect on reading skills. In addition, several potential moderators of the effect of retention on growth of mathematical and reading skills were identified including limited English language proficiency and children's conduct problems.

Short-Term Effects of Grade Retention on the Growth Rate of Woodcock-Johnson III Broad Math and Reading Scores

PubMed Central

Wu, Wei; West, Stephen G.; Hughes, Jan N.

2008-01-01

We investigated the effects of grade retention in first grade on the growth of the Woodcock-Johnson broad mathematics and reading scores over three years using linear growth curve modeling on an academically at-risk sample. A large sample (n = 784) of first grade children who were at risk for retention were initially identified based on low literacy scores. Scores representing propensity for retention were constructed based on 72 variables collected in comprehensive baseline testing in first grade. We closely matched 97 pairs of retained and promoted children based on their propensity scores using optimal matching procedures. This procedure adjusted for baseline differences between the retained and promoted children. We found that grade retention decreased the growth rate of mathematical skills but had no significant effect on reading skills. In addition, several potential moderators of the effect of retention on growth of mathematical and reading skills were identified including limited English language proficiency and children's conduct problems. PMID:19083352

A rational approach to fluid therapy in sepsis.

PubMed

Marik, P; Bellomo, R

2016-03-01

Aggressive fluid resuscitation to achieve a central venous pressure (CVP) greater than 8 mm Hg has been promoted as the standard of care, in the management of patients with severe sepsis and septic shock. However recent clinical trials have demonstrated that this approach does not improve the outcome of patients with severe sepsis and septic shock. Pathophysiologically, sepsis is characterized by vasoplegia with loss of arterial tone, venodilation with sequestration of blood in the unstressed blood compartment and changes in ventricular function with reduced compliance and reduced preload responsiveness. These data suggest that sepsis is primarily not a volume-depleted state and recent evidence demonstrates that most septic patients are poorly responsive to fluids. Furthermore, almost all of the administered fluid is sequestered in the tissues, resulting in severe oedema in vital organs and, thereby, increasing the risk of organ dysfunction. These data suggest that a physiologic, haemodynamically guided conservative approach to fluid therapy in patients with sepsis would be prudent and would likely reduce the morbidity and improve the outcome of this disease. © The Author 2015. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Student Retention at Prince George's Community College. Research Brief RB89-6.

ERIC Educational Resources Information Center

Clagett, Craig A.

A study was conducted at Prince George's Community College (PGCC) to examine student retention in two ways. First, the percentage of fall 1987 students who returned for classes the following spring was calculated for several student groups. Second, students entering PGCC for the first time in 1980 were tracked in terms of attendance and degree…

5 CFR 293.511 - Retention schedule.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Retention schedule. 293.511 Section 293.511 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PERSONNEL RECORDS Employee Medical File System Records § 293.511 Retention schedule. (a) Temporary EMFS records must...

5 CFR 293.511 - Retention schedule.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 5 Administrative Personnel 1 2013-01-01 2013-01-01 false Retention schedule. 293.511 Section 293.511 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PERSONNEL RECORDS Employee Medical File System Records § 293.511 Retention schedule. (a) Temporary EMFS records must...

5 CFR 293.511 - Retention schedule.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Retention schedule. 293.511 Section 293.511 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PERSONNEL RECORDS Employee Medical File System Records § 293.511 Retention schedule. (a) Temporary EMFS records must...

5 CFR 293.511 - Retention schedule.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 5 Administrative Personnel 1 2014-01-01 2014-01-01 false Retention schedule. 293.511 Section 293.511 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PERSONNEL RECORDS Employee Medical File System Records § 293.511 Retention schedule. (a) Temporary EMFS records must...

5 CFR 293.511 - Retention schedule.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 5 Administrative Personnel 1 2012-01-01 2012-01-01 false Retention schedule. 293.511 Section 293.511 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PERSONNEL RECORDS Employee Medical File System Records § 293.511 Retention schedule. (a) Temporary EMFS records must...

A strategic approach to employee retention.

PubMed

Gering, John; Conner, John

2002-11-01

A sound retention strategy should incorporate a business plan, a value proposition, progress measures, and management influences. The business plan will indicate whether a healthcare organization will achieve a return on investment for its effort. A value proposition will showcase an organization's strengths and differentiate it from its competitors. Measuring progress toward meeting retention goals at regular intervals will help keep an organization on track. The best managers require accountability, rewarding employees for their successes and taking corrective action as necessary. Retention rate targets must be at a level that will achieve a competitive advantage in the served market.

Liposome retention in size exclusion chromatography

PubMed Central

Ruysschaert, Tristan; Marque, Audrey; Duteyrat, Jean-Luc; Lesieur, Sylviane; Winterhalter, Mathias; Fournier, Didier

2005-01-01

Background Size exclusion chromatography is the method of choice for separating free from liposome-encapsulated molecules. However, if the column is not presaturated with lipids this type of chromatography causes a significant loss of lipid material. To date, the mechanism of lipid retention is poorly understood. It has been speculated that lipid binds to the column material or the entire liposome is entrapped inside the void. Results Here we show that intact liposomes and their contents are retained in the exclusion gel. Retention depends on the pore size, the smaller the pores, the higher the retention. Retained liposomes are not tightly fixed to the beads and are slowly released from the gels upon direct or inverted eluent flow, long washing steps or column repacking. Further addition of free liposomes leads to the elution of part of the gel-trapped liposomes, showing that the retention is transitory. Trapping reversibility should be related to a mechanism of partitioning of the liposomes between the stationary phase, water-swelled polymeric gel, and the mobile aqueous phase. Conclusion Retention of liposomes by size exclusion gels is a dynamic and reversible process, which should be accounted for to control lipid loss and sample contamination during chromatography. PMID:15885140

A magnetic fluid seal for rotary blood pumps: Behaviors of magnetic fluids in a magnetic fluid seal.

PubMed

Mitamura, Yoshinori; Yano, Tetsuya; Nakamura, Wataru; Okamoto, Eiji

2013-01-01

A magnetic fluid (MF) seal has excellent durability. The performance of an MF seal, however, has been reported to decrease in liquids (several days). We have developed an MF seal that has a shield mechanism. The seal was perfect for 275 days in water. To investigate the effect of a shield, behaviors of MFs in a seal in water were studied both experimentally and computationally. (a) Two kinds of MF seals, one with a shield and one without a shield, were installed in a centrifugal pump. Behaviors of MFs in the seals in water were observed with a video camera and high-speed microscope. In the seal without a shield, the surface of the water in the seal waved and the turbulent flow affected behaviors of the MFs. In contrast, MFs rotated stably in the seal with a shield in water even at high rotational speeds. (b) Computational fluid dynamics analysis revealed that a stationary secondary flow pattern in the seal and small velocity difference between magnetic fluid and water at the interface. These MF behaviors prolonged the life of an MF seal in water.

Environmental Stability and Infectivity of Hepatitis C Virus (HCV) in Different Human Body Fluids.

PubMed

Pfaender, Stephanie; Helfritz, Fabian A; Siddharta, Anindya; Todt, Daniel; Behrendt, Patrick; Heyden, Julia; Riebesehl, Nina; Willmann, Wiebke; Steinmann, Joerg; Münch, Jan; Ciesek, Sandra; Steinmann, Eike

2018-01-01

Background: Hepatitis C virus (HCV) is a hepatotropic, blood-borne virus, but in up to one-third of infections of the transmission route remained unidentified. Viral genome copies of HCV have been identified in several body fluids, however, non-parental transmission upon exposure to contaminated body fluids seems to be rare. Several body fluids, e.g., tears and saliva, are renowned for their antimicrobial and antiviral properties, nevertheless, HCV stability has never been systematically analyzed in those fluids. Methods: We used state of the art infectious HCV cell culture techniques to investigate the stability of HCV in different body fluids to estimate the potential risk of transmission via patient body fluid material. In addition, we mimicked a potential contamination of HCV in tear fluid and analyzed which impact commercially available contact lens solutions might have in such a scenario. Results: We could demonstrate that HCV remains infectious over several days in body fluids like tears, saliva, semen, and cerebrospinal fluid. Only hydrogen-peroxide contact lens solutions were able to efficiently inactivate HCV in a suspension test. Conclusion: These results indicate that HCV, once it is present in various body fluids of infected patients, remains infective and could potentially contribute to transmission upon direct contact.

7 CFR 3015.21 - Retention period.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 15 2010-01-01 2010-01-01 false Retention period. 3015.21 Section 3015.21 Agriculture Regulations of the Department of Agriculture (Continued) OFFICE OF THE CHIEF FINANCIAL OFFICER, DEPARTMENT OF AGRICULTURE UNIFORM FEDERAL ASSISTANCE REGULATIONS Record Retention and Access Requirements § 3015.21...

Emotional Intelligence and Nursing Student Retention

ERIC Educational Resources Information Center

Wilson, Victoria Jane

2013-01-01

The study examined the constructs of a Multi-Intelligence Model of Retention with four constructs: cognitive and emotional-social intelligence, student characteristics, and environmental factors. Data were obtained from sophomore students entering two diploma, nine associate, and five baccalaureate nursing programs. One year later, retention and…

12 CFR 609.945 - Records retention.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 12 Banks and Banking 6 2011-01-01 2011-01-01 false Records retention. 609.945 Section 609.945 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM ELECTRONIC COMMERCE Standards for Boards and Management § 609.945 Records retention. Records stored electronically must be accurate, accessible...

5 CFR 351.404 - Retention register.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Retention register. 351.404 Section 351.404 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS REDUCTION IN FORCE Scope of Competition § 351.404 Retention register. (a) When a competing employee is to be released...

5 CFR 351.404 - Retention register.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 5 Administrative Personnel 1 2014-01-01 2014-01-01 false Retention register. 351.404 Section 351.404 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS REDUCTION IN FORCE Scope of Competition § 351.404 Retention register. (a) When a competing employee is to be released...

5 CFR 351.404 - Retention register.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 5 Administrative Personnel 1 2012-01-01 2012-01-01 false Retention register. 351.404 Section 351.404 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS REDUCTION IN FORCE Scope of Competition § 351.404 Retention register. (a) When a competing employee is to be released...

5 CFR 351.404 - Retention register.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 5 Administrative Personnel 1 2013-01-01 2013-01-01 false Retention register. 351.404 Section 351.404 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS REDUCTION IN FORCE Scope of Competition § 351.404 Retention register. (a) When a competing employee is to be released...

5 CFR 351.404 - Retention register.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Retention register. 351.404 Section 351.404 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS REDUCTION IN FORCE Scope of Competition § 351.404 Retention register. (a) When a competing employee is to be released...

African Retentions in Blues and Jazz.

ERIC Educational Resources Information Center

Meadows, Eddie S.

1979-01-01

The perseverance of African musical characteristics among American Blacks is an historic reality. African retentions have been recorded in Black music of the antebellum period. Various African scales and rhythms permeate Black American music today as evidenced in the retentions found in blues and jazz. (RLV)

12 CFR 609.945 - Records retention.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Records retention. 609.945 Section 609.945 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM ELECTRONIC COMMERCE Standards for Boards and Management § 609.945 Records retention. Records stored electronically must be accurate, accessible...

Fluid mechanics in fluids at rest.

PubMed

Brenner, Howard

2012-07-01

Using readily available experimental thermophoretic particle-velocity data it is shown, contrary to current teachings, that for the case of compressible flows independent dye- and particle-tracer velocity measurements of the local fluid velocity at a point in a flowing fluid do not generally result in the same fluid velocity measure. Rather, tracer-velocity equality holds only for incompressible flows. For compressible fluids, each type of tracer is shown to monitor a fundamentally different fluid velocity, with (i) a dye (or any other such molecular-tagging scheme) measuring the fluid's mass velocity v appearing in the continuity equation and (ii) a small, physicochemically and thermally inert, macroscopic (i.e., non-Brownian), solid particle measuring the fluid's volume velocity v(v). The term "compressibility" as used here includes not only pressure effects on density, but also temperature effects thereon. (For example, owing to a liquid's generally nonzero isobaric coefficient of thermal expansion, nonisothermal liquid flows are to be regarded as compressible despite the general perception of liquids as being incompressible.) Recognition of the fact that two independent fluid velocities, mass- and volume-based, are formally required to model continuum fluid behavior impacts on the foundations of contemporary (monovelocity) fluid mechanics. Included therein are the Navier-Stokes-Fourier equations, which are now seen to apply only to incompressible fluids (a fact well-known, empirically, to experimental gas kineticists). The findings of a difference in tracer velocities heralds the introduction into fluid mechanics of a general bipartite theory of fluid mechanics, bivelocity hydrodynamics [Brenner, Int. J. Eng. Sci. 54, 67 (2012)], differing from conventional hydrodynamics in situations entailing compressible flows and reducing to conventional hydrodynamics when the flow is incompressible, while being applicable to both liquids and gases.

Hypereosinophilic Syndrome (HES)

MedlinePlus

... 5 (IL-5) monocolonal antibodies (mepolizumab and reslizumab). Systemic steroids are often needed to treat HES with organ involvement or with systemic symptoms, like severe rash, fluid retention, and similar. ...

Adolescents entering chemical dependency treatment in private managed care: ethnic differences in treatment initiation and retention.

PubMed

Campbell, Cynthia I; Weisner, Constance; Sterling, Stacy

2006-04-01

There has been little research on adolescents of different ethnicities in chemical dependency (CD) treatment, despite a focus on ethnic disparities in health care in recent years. In particular, little is known about ethnic differences in utilization of adolescent CD services. We examined treatment initiation and treatment retention in a sample of African American, Native American, Latino, Asian American, and Caucasian adolescents entering CD treatment in a private, managed care health plan (n = 419). Our conceptual framework included ethnicity as the main factor as well as measures of external pressure and internal motivation/readiness for treatment, family environment, psychiatric co-morbidities, and severity of alcohol and drug problems. Logistic and Poisson regression were used to examine differences. The study found ethnic differences in treatment initiation and treatment retention. Native American adolescents had lower odds of returning after intake to initiate treatment compared with Caucasians (odds ratio [OR] .35, p = .009), and African American youth spent less time in treatment than Caucasians (RR: .49, p < .001). Study findings indicate differences in treatment initiation for Native Americans and in treatment retention for African Americans. Intake and orientation sessions offer an opportunity to intervene with Native American youth. Given their high psychiatric co-morbidity, they may also benefit from the availability of psychiatric services. Even after adjusting for severity, we found shorter treatment retention for African American adolescents and suggest that organizational factors, such as cultural competency, may play an important role.

Devices with extended area structures for mass transfer processing of fluids

DOEpatents

TeGrotenhuis, Ward E.; Wegeng, Robert S.; Whyatt, Greg A.; King, David L.; Brooks, Kriston P.; Stenkamp, Victoria S.

2009-04-21

A microchannel device includes several mass transfer microchannels to receive a fluid media for processing at least one heat transfer microchannel in fluid communication with a heat transfer fluid defined by a thermally conductive wall, and at several thermally conductive fins each connected to the wall and extending therefrom to separate the mass transfer microchannels from one another. In one form, the device may optionally include another heat transfer microchannel and corresponding wall that is positioned opposite the first wall and has the fins and the mass transfer microchannels extending therebetween.

Black Student Retention in Higher Education.

ERIC Educational Resources Information Center

Lang, Marvel, Ed.; Ford, Clinita A., Ed.

This collection focuses on problems in the recruitment, enrollment and retention of Blacks in higher education in America. The following chapters are provided: "The Black Student Retention Problem in Higher Education: Some Introductory Perspectives" (Marvel Lang); "Early Acceptance and Institutional Linkages in a Model Program of Recruitment,…

Light's Retention Scale [and] Recording Form.

ERIC Educational Resources Information Center

Light, H. Wayne

Light's Retention Scale, consisting of 19 evaluation categories, is designed for use by teachers and school psychologists to determine whether a student should be retained in grade or promoted. Another suggested use is for nonprofessionals to determine what educational and psychological research discloses about a specific retention candidate in…

Retention of Nontraditional Students. Tip Sheet.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus. Instructional Materials Lab.

This publication begins with a list of suggestions for increasing the retention of male and female students pursuing nontraditional occupations. It then highlights five successful Ohio programs for the retention of these students: (1) Overcoming Sex Bias and Sex Stereotyping in Secondary Vocational Education--Nontraditional Support (Great Oaks…

Minority Teacher Recruitment and Retention Strategies

ERIC Educational Resources Information Center

Kearney-Gissendaner, Janet E.

2010-01-01

The tools and resources in this book help school leaders seamlessly incorporate minority teacher recruitment and retention programs into current human-resources activities. With details about exemplary minority teacher recruitment and retention programs, this book also showcases strategies for how to replicate such programs in your own school or…

The Tennessee Lottery Scholarship Program: Impact on Retention

ERIC Educational Resources Information Center

Puryear, Carol G.

2009-01-01

This study examined if the Tennessee Education Lottery Scholarship (TELS), which began in 2004, was related to student retention at the six Tennessee Board of Regents four-year institutions. This study investigated the impact of the TELS on student retention at TBR universities and general knowledge regarding retention. Post-facto data were…

Critical contribution of nonlinear chromatography to the understanding of retention mechanism in reversed-phase liquid chromatography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gritti, Fabrice; Guiochon, Georges A

2005-11-01

The retention of most compounds in RPLC proceeds through a combination of several independent mechanisms. We review a series of recent studies made on the behavior of several commercial C{sub 18}-bonded stationary phases and of the complex, mixed retention mechanisms that were observed in RPLC. These studies are essentially based on the acquisition of adsorption isotherm data, on the modeling, and on the interpretation of these data. Because linear chromatography deals only with the initial slope of the global, overall, or apparent isotherm, it is unable fully to describe the complete adsorption mechanism. It cannot even afford clues as tomore » the existence of several overlaid retention mechanisms. More specifically, it cannot account for the consequences of the surface heterogeneity of the packing material. The acquisition of equilibrium data in a wide concentration range is required for this purpose. Frontal analysis (FA) of selected probes gives data that can be modeled into equilibrium isotherms of these probes and that can also be used to calculate their adsorption or affinity energy distribution (AED). The combination of these data, the detailed study of the best constants of the isotherm model, the determination of the influence of experimental parameters (e.g., buffer pH and pI, temperature) on the isotherm constants provide important clues regarding the heterogeneity of the adsorbent surface and the main properties of the adsorption mechanisms. The comparison of similar data obtained for the adsorption of neutral and ionizable compounds, treated with the same approach, and the investigation of the influence on the thermodynamics of phase equilibrium of the experimental conditions (temperature, average pressure, mobile phase composition, nature of the organic modifier, and, for ionizable compounds, of the ionic strength, the nature, the concentration of the buffer, and its pH) brings further information. This review provides original conclusions

Effect of foliar-applied salicylic acid on cotton flowering, boll retention, and yield

Treesearch

J.J. Heitholt; J.H. Schmidt; Joseph E. Mulrooney

2001-01-01

Salicylic acid (2-hydroxybenzoic acid) may help regulate several plant functions, including systemic acquired resistance to pathogens and the formation of flowers. The objective of this study was to characterize the effects of foliar-applied salicylic acid on cotton (Gossypium hirsutum L.) flowering, boll retention, and yield. Field experiments were...

Creosote retention levels of timber highway bridge superstructures in Michigan’s Lower Peninsula.

Treesearch

James P. Wacker; Douglas M. Crawford; Merv O. Eriksson

2003-01-01

Environmental concerns about preservative bleeding (or migrating) from timber bridges have increased in recent years. This preliminary study examined the creosote retention levels at six timber highway bridges in Michigan's lower peninsula during the summer of 2000. Several test core samples were removed from the bridge superstructures (four bleeders and two...

The Space Shuttle orbiter payload retention systems

NASA Technical Reports Server (NTRS)

Hardee, J. H.

1982-01-01

Payloads are secured in the orbiter payload bay by the payload retention system or are equipped with their own unique retention systems. The orbiter payload retention mechanisms provide structural attachments for each payload by using four or five attachment points to secure the payload within the orbiter payload bay during all phases of the orbiter mission. The payload retention system (PRS) is an electromechanical system that provides standarized payload carrier attachment fittings to accommodate up to five payloads for each orbiter flight. The mechanisms are able to function under either l-g or zero-g conditions. Payload berthing or deberthing on orbit is accomplished by utilizing the remote manipulator system (RMS). The retention mechanisms provide the capability for either vertical or horizontal payload installation or removal. The payload support points are selected to minimize point torsional, bending, and radial loads imparted to the payloads. In addition to the remotely controlled latching system, the passive system used for nondeployable payloads performs the same function as the RMS except it provides fixed attachments to the orbiter.

Endocrine and fluid metabolism in males and females of different ages after bedrest, acceleration and lower body negative pressure

NASA Technical Reports Server (NTRS)

Leach, C. S.; Vernikos-Danellis, J.; Krauhs, J. M.; Sandler, H.

1985-01-01

Space shuttle flight simulations were conducted to determine the effects of weightlessness, lower body negative pressure (LBNP), and acceleration of fluid and electrolyte excretion and the hormones that control it. Measurements were made on male and female subjects of different ages before and after bedrest. After admission to a controlled environment, groups of 6 to 14 subjects in the age ranges 25 to 35, 35 to 45, 45 to 55 to 65 years were exposed to +3 G sub z for 15 minutes (G1) and to LBNP (LBNP1) on different days. On 3 days during this prebedrest period, no tests were conducted. Six days of bedrest followed, and the G sub z (G2) and LBNP (LBNP2) tests were run again. Hormones, electrolytes, and other parameters were measured in 24-hour urine pools throughout the experiment. During bedrest, cortisol and aldosterone excretion increased. Urine volume decreased, and specific gravity and osmolality increased. Urinary electrolytes were statistically unchanged from levels during the non-stress control period. During G2, cortisol increased significantly over its control and bedrest levels. Urine volume, sodium, and chloride were significantly lower; specific gravity and osmolality were higher during the control period or bedrest. The retention of fluids and electrolytes after +G sub z may at least partially explain decreased urine volume and increased osmolality observed during bedrest in this study. There were some who indicated that space flight would not affect the fluid and electrolyte metabolism of females or older males any more severely than it has affected that of male astronauts.

76 FR 34010 - Credit Risk Retention

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-10

... 2501-AD53 Credit Risk Retention AGENCIES: Office of the Comptroller of the Currency, Treasury (OCC... credit risk retention requirements of section 15G of the Securities Exchange Act of 1934, as added by the Dodd-Frank Wall Street Reform and Consumer Protection Act (``Credit Risk NPR'' or ``proposed rule...

5 CFR 9901.356 - Pay retention.

Code of Federal Regulations, 2011 CFR

2011-01-01

... retention. (b) Pay retention will be based on the employee's rate of base salary in effect immediately... offer to transfer with his or her function to a location outside the commuting area, or is identified... employee whose job is abolished declines an offer within the competitive area, but outside the commuting...

Teacher Decision-Making in Student Retention.

ERIC Educational Resources Information Center

Cross, Ray

This investigation at a southern Texas school district examined three factors that bear on teachers' decisions to recommend first- and second-grade students for retention: (1) criteria used by teachers, (2) degree to which criteria are common among teachers, and (3) relationship of recommendations for promotion or retention to objective measures…

Affairs of State and Student Retention: An Exploratory Study of the Factors that Impact Student Retention in a Politically Turbulent Region

ERIC Educational Resources Information Center

Ben-Tsur, Dalia

2007-01-01

This study examines the impact of a country's security unrest on student retention. It draws on the key factors that influence retention worldwide, adopts Bourdieu's notion of cultural capital and also brings in concepts related to terrorism and security unrest traditionally absent from theories on student retention. Based on a case study carried…

Factors affecting the retention of nurses. A survival analysis.

PubMed

Alonazi, Noufa A; Omar, Maye A

2013-03-01

To identify and explore factors that mostly influence nurses' turnover and retention, and to estimate the length of employment for nurses in the hospital. This is a retrospective cohort study examining the standard Exit Questionnaires completed by all the female pediatric nurses who joined and left the hospital during the period between January 2006 and October 2010. The Developed Questionnaires where completed by nurses who were still employees in October 2010. The nurses who left the job will be considered as events and the nurses who are still working will be considered as censored. The study took place at the Pediatric Department, Prince Sultan Military Medical City (PSMMC), Riyadh, Saudi Arabia. A total of 254 nurses were included in the study. Most of the nurses left their jobs due to family reasons (39.7%) followed by other reasons (37.3%). Seventy five percent of all the pediatric nurses remained in their jobs, on average, for 2.2 years. Both simple and multivariate analysis indicated a strong positive correlation between length of employment (turnover) and the demographic and organization factors. This study has identified several factors that played a key role in staff retention, which can help in predicting nursing turnover at PSMMC. The findings of this study could help PSMMC and its Nursing Administration, in particular, to understand the seriousness of the high turnover rates, to develop and implement strategies to reduce this problem, and improve the retention of nursing staff.

Enantioseparation of novel chiral sulfoxides on chlorinated polysaccharide stationary phases in supercritical fluid chromatography.

PubMed

West, Caroline; Konjaria, Mari-Luiza; Shashviashvili, Natia; Lemasson, Elise; Bonnet, Pascal; Kakava, Rusudan; Volonterio, Alessandro; Chankvetadze, Bezhan

2017-05-26

Asymmetric sulfoxides is a particular case of chirality that may be found in natural as well as synthetic products. Twenty-four original molecules containing a sulfur atom as a centre of chirality were analyzed in supercritical fluid chromatography on seven polysaccharide-based chiral stationary phases (CSP) with carbon dioxide - methanol mobile phases. While all the tested CSP provided enantioseparation for a large part of the racemates, chlorinated cellulosic phases proved to be both highly retentive and highly enantioselective towards these species. Favourable structural features were determined by careful comparison of the enantioseparation of the probe molecules. Molecular modelling studies indicate that U-shaped (folded) conformations were most favorable to achieve high enantioresolution on these CSP, while linear (extended) conformations were not so clearly discriminated. For a subset of these species adopting different conformations, a broad range of mobile phase compositions, ranging from 20 to 100% methanol in carbon dioxide, were investigated. While retention decreased continuously in this range, enantioseparation varied in a non-monotonous fashion. Abrupt changes in the tendency curves of retention and selectivity were observed when methanol proportion reaches about 60%, suggesting that a change in the conformation of the analytes and/or chiral selector is occurring at this point. Copyright © 2017 Elsevier B.V. All rights reserved.

A systematic review of interventions to improve postpartum retention of women in PMTCT and ART care

PubMed Central

Geldsetzer, Pascal; Yapa, H Manisha N; Vaikath, Maria; Ogbuoji, Osondu; Fox, Matthew P; Essajee, Shaffiq M; Negussie, Eyerusalem K; Bärnighausen, Till

2016-01-01

Introduction The World Health Organization recommends lifelong antiretroviral therapy (ART) for all pregnant and breastfeeding women living with HIV. Effective transitioning from maternal and child health to ART services, and long-term retention in ART care postpartum is crucial to the successful implementation of lifelong ART for pregnant women. This systematic review aims to determine which interventions improve (1) retention within prevention of mother-to-child HIV transmission (PMTCT) programmes after birth, (2) transitioning from PMTCT to general ART programmes in the postpartum period, and (3) retention of postpartum women in general ART programmes. Methods We searched Medline, Embase, ISI Web of Knowledge, the regional World Health Organization databases and conference abstracts for data published between 2002 and 2015. The quality of all included studies was assessed using the GRADE criteria. Results and Discussion After screening 8324 records, we identified ten studies for inclusion in this review, all of which were from sub-Saharan Africa except for one from the United Kingdom. Two randomized trials found that phone calls and/or text messages improved early (six to ten weeks) postpartum retention in PMTCT. One cluster-randomized trial and three cohort studies found an inconsistent impact of different levels of integration between antenatal care/PMTCT and ART care on postpartum retention. The inconsistent results of the four identified studies on care integration are likely due to low study quality, and heterogeneity in intervention design and outcome measures. Several randomized trials on postpartum retention in HIV care are currently under way. Conclusions Overall, the evidence base for interventions to improve postpartum retention in HIV care is weak. Nevertheless, there is some evidence that phone-based interventions can improve retention in PMTCT in the first one to three months postpartum. PMID:27118443

Indocyanine green retention test (ICG-r15) as a noninvasive predictor of portal hypertension in patients with different severity of cirrhosis.

PubMed

Pind, Marie-Louise L; Bendtsen, Flemming; Kallemose, Thomas; Møller, Søren

2016-08-01

Portal hypertension is a severe consequence of chronic liver disease, responsible for the main clinical complications of cirrhosis. Measurement of the hepatic venous pressure gradient (HVPG) provides important clinical information, but the procedure is invasive and demands expert skills of the staff.In the present study, we aimed to investigate the relationship between the constant infusion indocyanine green (ICG) clearance, the calculated ICG retention test after 15 min (ICG-r15), and HVPG in patients with different severity of cirrhosis for validation of ICG-r15 as a noninvasive predictor of portal hypertension. A total of 325 patients were studied. During a hemodynamic investigation, the ICG clearance was determined using the constant infusion technique and ICG-r15 was calculated. Assessment of the diagnostic performance of ICG clearance and ICG-r15 as predictors of HVPG above 10 mmHg was performed by receiver operating characteristic curve analyses.The ICG clearance and ICG-r15 performed well in all three Child classes, with the most significant results among Child class A patients [area under the receiver operating characteristic (AUROC)=0.832] and less significant results in Child class B (AUROC=0.7448) and Child class C patients (AUROC=0.7392). Only six out of 102 patients in Child class C had HVPG of less than 12 mmHg. ICG-r15 can be used as an indirect assessment of significant portal hypertension in compensated cirrhotic patients. ICG-r15 may be suitable as a screening tool for the identification of patients for endoscopy and measurement of HVPG.Further validation of ICG-r15 together with other predictors of portal hypertension and its clinical use is encouraged.

32 CFR 240.6 - Retention program.

Code of Federal Regulations, 2014 CFR

2014-07-01

... INFORMATION ASSURANCE SCHOLARSHIP PROGRAM (IASP) § 240.6 Retention program. (a) The DoD IASP retention program... Force Institute of Technology (AFIT) at Wright-Patterson Air Force Base in Dayton, Ohio; the IRMC of the... education, to continue service within the DoD upon conclusion of their education, for a period equal to...

Fluid imbalance

MedlinePlus

... up in the body. This is called fluid overload (volume overload). This can lead to edema (excess fluid in ... Water imbalance; Fluid imbalance - dehydration; Fluid buildup; Fluid overload; Volume overload; Loss of fluids; Edema - fluid imbalance; ...

Interfacial fluid instabilities and Kapitsa pendula.

PubMed

Krieger, Madison S

2017-07-01

The onset and development of instabilities is one of the central problems in fluid mechanics. Here we develop a connection between instabilities of free fluid interfaces and inverted pendula. When acted upon solely by the gravitational force, the inverted pendulum is unstable. This position can be stabilized by the Kapitsa phenomenon, in which high-frequency low-amplitude vertical vibrations of the base creates a fictitious force which opposes the gravitational force. By transforming the dynamical equations governing a fluid interface into an appropriate pendulum-type equation, we demonstrate how stability can be induced in fluid systems by properly tuned vibrations. We construct a "dictionary"-type relationship between various pendula and the classical Rayleigh-Taylor, Kelvin-Helmholtz, Rayleigh-Plateau and the self-gravitational instabilities. This makes several results in control theory and dynamical systems directly applicable to the study of tunable fluid instabilities, where the critical wavelength depends on the external forces or the instability is suppressed entirely. We suggest some applications and instances of the effect ranging in scale from microns to the radius of a galaxy.

Retention of Content Utilizing a Flipped Classroom Approach.

PubMed

Shatto, Bobbi; LʼEcuyer, Kristine; Quinn, Jerod

The flipped classroom experience promotes retention and accountability for learning. The authors report their evaluation of a flipped classroom for accelerated second-degree nursing students during their primary medical-surgical nursing course. Standardized HESI® scores were compared between a group of students who experienced the flipped classroom and a previous group who had traditional teaching methods. Short- and long-term retention was measured using standardized exams 3 months and 12 months following the course. Results indicated that short-term retention was greater and long- term retention was significantly great in the students who were taught using flipped classroom methodology.

Enhanced vaginal drug delivery through the use of hypotonic formulations that induce fluid uptake

PubMed Central

Ensign, Laura M.; Hoen, Timothy; Maisel, Katharina; Cone, Richard; Hanes, Justin

2013-01-01

Mucosal epithelia use osmotic gradients for fluid absorption and secretion. We hypothesized that administration of hypotonic solutions would induce fluid uptake that could be advantageous for rapidly delivering drugs through mucus to the vaginal epithelium. We found that hypotonic formulations markedly increased the rate at which small molecule drugs and muco-inert nanoparticles (mucus-penetrating particles, or MPP), but not conventional mucoadhesive nanparticles (CP), reached the vaginal epithelial surface in vivo in mice. Additionally, hypotonic formulations greatly enhanced drug and MPP delivery to the entire epithelial surface, including deep into the vaginal folds (rugae) that drugs or MPP in isotonic formulations failed to reach efficiently. However, hypotonic formulations caused unencapsulated “free” drugs to be drawn through the epithelium, reducing vaginal retention. In contrast, hypotonic formulations caused MPP to accumulate rapidly and uniformly on vaginal surfaces, ideally positioned for localized sustained drug delivery. Using a mouse model of vaginal genital herpes (HSV-2) infection, we found that hypotonic delivery of free drug led to improved immediate protection, but diminished longer-term protection. In contrast, as we previously demonstrated, hypotonic delivery of drug via MPP led to better long-term retention and protection in the vagina. Importantly, we demonstrate that slightly hypotonic formulations provided rapid and uniform delivery of MPP to the entire vaginal surface, thus enabling formulations with minimal risk of epithelial toxicity. Hypotonic formulations for vaginal drug delivery via MPP may significantly improve prevention and treatment of reproductive tract diseases and disorders. PMID:23769419

Mucous retention cyst of the maxillary sinus.

PubMed

Ruprecht, A; Batniji, S; el-Neweihi, E

1986-12-01

The mucous retention cyst is not a rare phenomenon. The incidence of dental patients was determined. Of 1685 patient radiographs reviewed, 44 (2.6%) had one or more mucous retention cysts in the maxillary sinuses.

Amniotic Fluid Cells Show Higher Pluripotency-Related Gene Expression Than Allantoic Fluid Cells.

PubMed

Kehl, Debora; Generali, Melanie; Görtz, Sabrina; Geering, Diego; Slamecka, Jaroslav; Hoerstrup, Simon P; Bleul, Ulrich; Weber, Benedikt

2017-10-01

Amniotic fluid represents an abundant source of multipotent stem cells, referred as broadly multipotent given their differentiation potential and expression of pluripotency-related genes. However, the origin of this broadly multipotent cellular fraction is not fully understood. Several sources have been proposed so far, including embryonic and extraembryonic tissues. In this regard, the ovine developmental model uniquely allows for direct comparison of fetal fluid-derived cells from two separate fetal fluid cavities, the allantois and the amnion, over the entire duration of gestation. As allantoic fluid mainly collects fetal urine, cells originating from the efferent urinary tract can directly be compared with cells deriving from the extraembryonic amniotic tissues and the fetus. This study shows isolation of cells from the amniotic [ovine amniotic fluid cells (oAFCs)] and allantoic fluid [ovine allantoic fluid cells (oALCs)] in a strictly paired fashion with oAFCs and oALCs derived from the same fetus. Both cell types showed cellular phenotypes comparable to standard mesenchymal stem cells (MSCs), with trilineage differentiation potential, and expression of common ovine MSC markers. However, the expression of MSC markers per single cell was higher in oAFCs as measured by flow cytometry. oAFCs exhibited higher proliferative capacities and showed significantly higher expression of pluripotency-related genes OCT4, STAT3, NANOG, and REX1 by quantitative real-time polymerase chain reaction compared with paired oALCs. No significant decrease of pluripotency-related gene expression was noted over gestation, implying that cells with high differentiation potential may be isolated at the end of pregnancy. In conclusion, this study suggests that cells with highest stem cell characteristics may originate from the fetus itself or the amniotic fetal adnexa rather than from the efferent urinary tract or the allantoic fetal adnexa.

Influence of polymeric carrier on the disposition and retention of 20(R)-ginsenoside-rg3-loaded swellable microparticles in the lung.

PubMed

Wang, Xiuhua; Zhang, Xiao; Fan, Linlin; He, Huan; Zhang, Xiaofei; Zhang, Yuyang; Mao, Shirui

2018-02-01

The objective of this study was to investigate the influence of differently charged biocompatible polymers, including chitosan (CS), hyaluronic acid (HA), and hydroxypropyl cellulose (HPC), on the disposition and retention of 20(R)-ginsenoside-rg3 (Rg3)-loaded swellable microparticles in the lung. A high-pressure homogenization method combined with spray drying was used to prepare Rg3-loaded microparticles. In vitro aerodynamic performance of different microparticles was characterized by the Next Generation Impactor (NGI). Retention of the swellable microparticles in the rat lung was investigated using bronchoalveolar lavage fluid method. Influence of drug loading, polymer molecular weight, and polymer charge on the properties of the swellable microparticles was investigated. It was found that drug loading had no significant influence on experimental mass median aerodynamic diameter (MMAD e ) and fine particle fraction (FPF). Increasing polymer molecular weight caused no remarkable change in MMAD e value, but the FPF value decreased with the increase of polymer molecular weight. At the same molecular weight level, polymer structure and charge had no statistical influence on the in vitro aerodynamic properties of the microparticles and lung disposition, but it influenced the swelling and bioadhesion behavior and therefore lung retention profile. Desirable phagocytosis escapement and inhibition of A549 cell proliferation were achieved for the developed swellable microparticles. In conclusion, the lung retention of swellable microparticles can be adjusted by selecting polymeric carriers with different structure and charge.

Assessing Chemical Retention Process Controls in Ponds

NASA Astrophysics Data System (ADS)

Torgersen, T.; Branco, B.; John, B.

2002-05-01

Small ponds are a ubiquitous component of the landscape and have earned a reputation as effective chemical retention devices. The most common characterization of pond chemical retention is the retention coefficient, Ri= ([Ci]inflow-[Ci] outflow)/[Ci]inflow. However, this parameter varies widely in one pond with time and among ponds. We have re-evaluated literature reported (Borden et al., 1998) monthly average retention coefficients for two ponds in North Carolina. Employing a simple first order model that includes water residence time, the first order process responsible for species removal have been separated from the water residence time over which it acts. Assuming the rate constant for species removal is constant within the pond (arguable at least), the annual average rate constant for species removal is generated. Using the annual mean rate constant for species removal and monthly water residence times results in a significantly enhanced predictive capability for Davis Pond during most months of the year. Predictive ability remains poor in Davis Pond during winter/unstratified periods when internal loading of P and N results in low to negative chemical retention. Predictive ability for Piedmont Pond (which has numerous negative chemical retention periods) is improved but not to the same extent as Davis Pond. In Davis Pond, the rate constant for sediment removal (each month) is faster than the rate constant for water and explains the good predictability for sediment retention. However, the removal rate constant for P and N is slower than the removal rate constant for sediment (longer water column residence time for P,N than for sediment). Thus sedimentation is not an overall control on nutrient retention. Additionally, the removal rate constant for P is slower than for TOC (TOC is not the dominate removal process for P) and N is removed slower than P (different in pond controls). For Piedmont Pond, sediment removal rate constants are slower than the removal

Anthropometric changes and fluid shifts

NASA Technical Reports Server (NTRS)

Thornton, W. E.; Hoffler, G. W.; Rummel, J. A.

1974-01-01

Several observations of body size, shape, posture, and configuration were made to document changes resulting from direct effects of weightlessness during the Skylab 4 mission. After the crewmen were placed in orbit, a number of anatomical and anthropometric changes occurred including a straightening of the thoracolumbar spine, a general decrease in truncal girth, and an increase in height. By the time of the earliest in-flight measurement on mission day 3, all crewmen had lost more than two liters of extravascular fluid from the calf and thigh. The puffy facies, the bird legs effect, the engorgement of upper body veins, and the reduced volume of lower body veins were all documented with photographs. Center-of-mass measurements confirmed a fluid shift cephalad. This shift remained throughout the mission until recovery, when a sharp reversal occurred; a major portion of the reversal was completed in a few hours. The anatomical changes are of considerable scientific interest and of import to the human factors design engineer, but the shifts of blood and extravascular fluid are of more consequence. It is hypothesized that the driving force for the fluid shift is the intrinsic and unopposed lower limb elasticity that forces venous blood and then other fluid cephalad.

[Cerebral vasospasm and lipid peroxidation--lipid peroxides in the cerebrospinal fluid after subarachnoid hemorrhage].

PubMed

Sasaki, T; Asano, T; Takakura, K; Sano, K; Nakamura, T; Suzuki, N; Imabayashi, S; Ishikawa, Y

1982-12-01

The relationship between lipid peroxides in cerebrospinal fluid (CSF) and the occurrence of cerebral vasospasm following subarachnoid hemorrhage (SAH) was evaluated by analyzing CSF with high-performance liquid chromatography (HPLC) and gas chromatography mass spectrometry (GC-MS). Hydroperoxy eicosatetraenoic acids (HPETEs) and hydroxy eicosatetraenoic acids (HETEs) were synthesized by the treatment of arachidonic acid with hydrogen peroxide and cupric chloride. The retention time of these HPETEs and HETEs were determined on HPLC. The position of oxydation occurred was determined after methylation, reduction and trimethyl silylation using GC-MS. Thus the elucidation of positional isomers of HPETEs and HETEs was made possible by the retention time on HPLC. The supernant of CSF after SAH was adjusted to pH 3.0 and then absorbed to octadecyl silyl silica column. The eluted fraction with 15% ethanol-water from octadecyl silyl silica column was analyzed by HPLC detecting at 238 nm. No peak was observed on HPLC at the region of HPETEs and HETEs in the CSF obtained from healthy person. In SAH patients, several peaks were recognized in accordance with the occurrence of cerebral vasospasm. One of the peaks was identified as 5-HETE by HPLC and GC-MS. In 10 SAH patients, semi-quantitative analysis of 5-HETE in the CSF was performed by measuring the height of the peak identified as 5-HETE on HPLC. The close correlation was recognized between the occurrence of cerebral vasospasm and the appearance of 5-HETE in the CSF. The results of the present study suggest that lipid peroxidation is involved in the pathogenesis of chronic vasospasm after SAH.

Mannitol improves absorption and retention of calcium and magnesium in growing rats.

PubMed

Xiao, Jin; Li, Xiao; Min, Xiao; Sakaguchi, Ei

2013-01-01

Resistant sugars, which have several desirable properties, are often used in food production and the pharmaceutical industry. We evaluated the effects of mannitol on the absorption and retention of calcium (Ca) and magnesium (Mg) in growing rats. In experiment 1, 4-wk-old growing male Wistar rats were given a control diet (C) or mannitol diets containing 2%, 4%, 6%, or 8% mannitol (2M, 4M, 6M, or 8M, respectively) for 28 d to measure the absorption and retention of Ca and Mg. In the last 7 d of the feeding trial, the non-absorbable marker chromium-mordant cellulose was added to the experimental diets to estimate Ca and Mg absorbability in the intestinal segments. In experiment 2, 9-wk-old growing male Wistar rats were fed for 7 d with the experimental diets (C, 4M, or 8M) to observe cecal parameters. Apparent Ca absorption and retention in bone were significantly increased by 6M and 8M. Apparent Mg absorption was significantly increased by 4M, 6M, and 8M, whereas Mg retention in bone was significantly increased by 8M. The Ca/Cr and Mg/Cr in cecal digesta were similar in all groups. Fecal Ca/Cr was significantly decreased by 6M and 8M and Mg/Cr was significantly decreased by 4M, 6M, and 8M. In experiment 2, cecal weight and tissue weight were significantly increased by 8M. A significant decrease in pH was concomitant with a significant change in cecal organic acid concentrations after mannitol consumption. Absorption and retention of Ca and Mg are promoted by mannitol feeding through the fermentation of mannitol in the cecum. Copyright © 2013 Elsevier Inc. All rights reserved.

Understanding Fluid Shifts in the Brain: Choroidal Regulation Involved in the Cerebral Fluid Response to Altered Gravity

NASA Technical Reports Server (NTRS)

Gabrion, Jaqueline; Vasques, Marilyn; Aquilina, Rudy (Technical Monitor)

2002-01-01

Fluid balance and regulation of body fluid production are critical aspects of life and survival on Earth. In space, without gravity exerting its usual downward pulling effect, the fluids of the human body shift in an unnatural, headward direction. After awhile, humans and other mammalian species adapt to the microgravity environment which leads to changes in the regulation and distribution of these body fluids. Previous spaceflight experiments have indicated that production of fluid in the brain and spinal cord, cerebrospinal fluid (CSF), might be reduced in rats exposed to microgravity. In this experiment conducted by Dr. Jacqueline Gabrion (University of Pierre and Marie Curie, France), proteins important for CSF production, and several molecules that regulate water and mineral transport, will be investigated in rats flown on the Shuttle. Dr. Gabrion and her team will determine the amounts of these proteins and molecules present in the brain in order to evaluate whether any changes have taken place during the rats' adaptation to microgravity. The levels of different aquaporins (proteins that act as a channel for water transport in and out of cells) will also be investigated in other areas of the brain and body to better understand the regulatory responses affecting these important water channel proteins. In addition to producing essential and basic information about fluid production in the brain and body, this experiment will reveal fundamental information about the mechanisms involved in cerebral adaptation and fluid balance during spaceflight.

Alcohol-related legal infractions and student retention.

PubMed

Thompson, Kevin M

2007-09-01

The present study employed municipal alcohol-related arrest reports to determine if being arrested/cited reduced the probability of academic retention. Alcohol-related legal infraction data implicating 1,310 college students was gathered during a 4-year period. First- through third-year students were identified in the database by cross-checking names in the campus directory. A random sample of nonarrested students functioned as the comparison group (n = 856). Students not appearing in the directory the following year were defined as nonretained students. Retention was not affected by the experience of one alcohol-related legal infraction. Retention odds were 31% lower for students experiencing multiple arrests, however, than for nonarrested or single-arrested students. Gender moderated the association between arrest and retention, with women who had been arrested more likely to return to school than those who had not been arrested. Retention odds were higher for arrested/cited students if they were in their second or third year of college, a fraternity/sorority member, or charged with an offense other than driving under the influence. Multi-arrested college students are at risk for attrition. Immersion in college life may reduce the odds of attrition among arrested college students.

49 CFR 239.203 - Retention of emergency preparedness plan.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Retention of emergency preparedness plan. 239.203... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION PASSENGER TRAIN EMERGENCY PREPAREDNESS Review, Approval, and Retention of Emergency Preparedness Plans § 239.203 Retention of emergency preparedness plan. Each passenger...

Behavior of fluids in a weightless environment

NASA Technical Reports Server (NTRS)

Fester, D. A.; Eberhardt, R. N.; Tegart, J. R.

1977-01-01

Fluid behavior in a low-g environment is controlled primarily by surface tension forces. Certain fluid and system characteristics determine the magnitude of these forces for both a free liquid surface and liquid in contact with a solid. These characteristics, including surface tension, wettability or contact angle, system geometry, and the relationships governing their interaction, are discussed. Various aspects of fluid behavior in a low-g environment are then presented. This includes the formation of static interface shapes, oscillation and rotation of drops, coalescence, the formation of foams, tendency for cavitation, and diffusion in liquids which were observed during the Skylab fluid mechanics science demonstrations. Liquid reorientation and capillary pumping to establish equilibrium configurations for various system geometries, observed during various free-fall (drop-tower) low-g tests, are also presented. Several passive low-g fluid storage and transfer systems are discussed. These systems use surface tension forces to control the liquid/vapor interface and provide gas-free liquid transfer and liquid-free vapor venting.

Urinary retention associated with herpes zoster infection.

PubMed

Cohen, L M; Fowler, J F; Owen, L G; Callen, J P

1993-01-01

Herpes zoster infection particularly involving the sacral dermatomes has been associated with bladder and bowel dysfunction, most commonly urinary retention. We report two patients who developed acute urinary retention, one of whom also had constipation, within days of herpes zoster skin lesions of the S2-S4 dermatomes. Herpes zoster is a reversible cause of neurogenic bladder and bowel dysfunction and should be considered in a patient that presents with acute urinary retention and/or constipation. Sensory abnormalities and flaccid detrusor paralysis are most likely involved in the pathogenesis.

Strategies to improve retention in randomised trials.

PubMed

Brueton, Valerie C; Tierney, Jayne; Stenning, Sally; Harding, Seeromanie; Meredith, Sarah; Nazareth, Irwin; Rait, Greta

2013-12-03

Loss to follow-up from randomised trials can introduce bias and reduce study power, affecting the generalisability, validity and reliability of results. Many strategies are used to reduce loss to follow-up and improve retention but few have been formally evaluated. To quantify the effect of strategies to improve retention on the proportion of participants retained in randomised trials and to investigate if the effect varied by trial strategy and trial setting. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PreMEDLINE, EMBASE, PsycINFO, DARE, CINAHL, Campbell Collaboration's Social, Psychological, Educational and Criminological Trials Register, and ERIC. We handsearched conference proceedings and publication reference lists for eligible retention trials. We also surveyed all UK Clinical Trials Units to identify further studies. We included eligible retention trials of randomised or quasi-randomised evaluations of strategies to increase retention that were embedded in 'host' randomised trials from all disease areas and healthcare settings. We excluded studies aiming to increase treatment compliance. We contacted authors to supplement or confirm data that we had extracted. For retention trials, we recorded data on the method of randomisation, type of strategy evaluated, comparator, primary outcome, planned sample size, numbers randomised and numbers retained. We used risk ratios (RR) to evaluate the effectiveness of the addition of strategies to improve retention. We assessed heterogeneity between trials using the Chi(2) and I(2) statistics. For main trials that hosted retention trials, we extracted data on disease area, intervention, population, healthcare setting, sequence generation and allocation concealment. We identified 38 eligible retention trials. Included trials evaluated six broad types of strategies to improve retention. These were incentives, communication strategies, new questionnaire format, participant case

Drug Retention Times

DOE Office of Scientific and Technical Information (OSTI.GOV)

Center for Human Reliability Studies

The purpose of this monograph is to provide information on drug retention times in the human body. The information provided is based on plausible illegal drug use activities that might be engaged in by a recreational drug user.

48 CFR 1604.705 - Specific retention periods.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 48 Federal Acquisition Regulations System 6 2012-10-01 2012-10-01 false Specific retention periods. 1604.705 Section 1604.705 Federal Acquisition Regulations System OFFICE OF PERSONNEL MANAGEMENT FEDERAL EMPLOYEES HEALTH BENEFITS ACQUISITION REGULATION GENERAL ADMINISTRATIVE MATTERS Contractor Records Retention...

48 CFR 1604.705 - Specific retention periods.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 48 Federal Acquisition Regulations System 6 2013-10-01 2013-10-01 false Specific retention periods. 1604.705 Section 1604.705 Federal Acquisition Regulations System OFFICE OF PERSONNEL MANAGEMENT FEDERAL EMPLOYEES HEALTH BENEFITS ACQUISITION REGULATION GENERAL ADMINISTRATIVE MATTERS Contractor Records Retention...

48 CFR 1604.705 - Specific retention periods.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 48 Federal Acquisition Regulations System 6 2011-10-01 2011-10-01 false Specific retention periods. 1604.705 Section 1604.705 Federal Acquisition Regulations System OFFICE OF PERSONNEL MANAGEMENT FEDERAL EMPLOYEES HEALTH BENEFITS ACQUISITION REGULATION GENERAL ADMINISTRATIVE MATTERS Contractor Records Retention...

48 CFR 1604.705 - Specific retention periods.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 48 Federal Acquisition Regulations System 6 2014-10-01 2014-10-01 false Specific retention periods. 1604.705 Section 1604.705 Federal Acquisition Regulations System OFFICE OF PERSONNEL MANAGEMENT FEDERAL EMPLOYEES HEALTH BENEFITS ACQUISITION REGULATION GENERAL ADMINISTRATIVE MATTERS Contractor Records Retention...

48 CFR 1604.705 - Specific retention periods.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Specific retention periods. 1604.705 Section 1604.705 Federal Acquisition Regulations System OFFICE OF PERSONNEL MANAGEMENT FEDERAL EMPLOYEES HEALTH BENEFITS ACQUISITION REGULATION GENERAL ADMINISTRATIVE MATTERS Contractor Records Retention...

Retention of urine and sacral paraesthesia in anogenital herpes simplex infection.

PubMed

Edis, R H

1981-01-01

Two definite and 2 probable cases of anogenital herpes simplex and sacral radiculitis are described. Symptoms were typical and consisted of paraesthesia and neuralgic pain in the perineum and legs, urinary retention and constipation occurring within several days to a week after an anogenital herpetic eruption. However, at presentation only 1 case had an obvious history of anogenital herpes simplex. Neurological signs were not striking and consisted of a reduced appreciation of light touch and pin prick over the sacral dermatomes and in 2 cases reduced anal sphincter tone. CSF examination in 3 patients showed a lymphocytosis. Bladder catheterisation was required for up to 2 weeks in 2 patients. The paraesthesia persisted for weeks to months. It should be more widely recognised that anogenital herpes simplex, with sacral radiculitis, is probably the commonest cause of acute retention of urine in young sexually active people.

Proteome analysis of pitcher fluid of the carnivorous plant Nepenthes alata.

PubMed

Hatano, Naoya; Hamada, Tatsuro

2008-02-01

The genus Nepenthes comprises carnivorous plants that digest insects in pitcher fluid to supplement their nitrogen uptake. In a recent study, two acid proteinases (nepenthesins I and II) were purified from the pitcher fluid. However, no other enzymes involved in prey digestion have been identified, although several enzyme activities have been reported. To identify all the proteins involved, we performed a proteomic analysis of Nepenthes pitcher fluid. The secreted proteins in pitcher fluid were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and several protein bands were detected by silver staining. The proteins were identified by in-gel tryptic digestion, de novo peptide sequencing, and homology searches against public databases. The proteins included homologues of beta-D-xylosidase, beta-1,3-glucanase, chitinase, and thaumatin-like protein, most of which are designated "pathogenesis-related proteins". These proteins presumably inhibit bacterial growth in the pitcher fluid to ensure sufficient nutrients for Nepenthes growth.

To Evaluate & Compare Retention of Complete Cast Crown in Natural Teeth Using Different Auxiliary Retentive Features with Two Different Crown Heights - An In Vitro Study.

PubMed

Vinaya, Kundapur; Rakshith, Hegde; Prasad D, Krishna; Manoj, Shetty; Sunil, Mankar; Naresh, Shetty

2015-06-01

To evaluate the retention of complete cast crowns in teeth with adequate and inadequate crown height and to evaluate the effects of auxiliary retentive features on retention form complete cast crowns. Sixty freshly extracted human premolars. They were divided into 2 major groups depending upon the height of the teeth after the preparation. Group1 (H1): prepared teeth with constant height of 3.5 mm and Group 2 (H2): prepared teeth with constant height of 2.5 mm. Each group is further subdivided into 3 subgroups, depending upon the retentive features incorporated. First sub group were prepared conventionally, second sub group with proximal grooves and third subgroups with proximal boxes preparation. Castings produced in Nickel chromium alloy were cemented with glass ionomer cement and the cemented castings were subjected to tensional forces required to dislodge each cemented casting from its preparation and used for comparison of retentive quality. The data obtained were statistically analyzed using Oneway ANOVA test. The results showed there was statistically significant difference between adequate (H1) and inadequate (H2) group and increase in retention when there was incorporation of retentive features compared to conventional preparations. Incorporation of retentive grooves was statistically significant compared to retention obtained by boxes. Results also showed there was no statistically significant difference between long conventional and short groove. Complete cast crowns on teeth with adequate crown height exhibited greater retention than with inadequate crown height. Proximal grooves provided greater amount of retention when compared with proximal boxes.

Caffeine-containing beverages, total fluid consumption, and premenstrual syndrome.

PubMed

Rossignol, A M; Bonnlander, H

1990-09-01

The main objective of this study was to evaluate whether daily consumption of caffeine-containing beverages is related to the prevalence and severity of premenstrual syndrome apart from any effects of daily total fluid consumption. A secondary objective was to determine whether daily total fluid consumption itself is related to premenstrual syndrome. The study is based on 841 responses to a questionnaire probing menstrual and premenstrual health, and daily fluid consumption, which was mailed to female university students in Oregon. Analysis of the data revealed that consumption of caffeine-containing beverages was strongly related to the prevalence of premenstrual syndrome. Among women with more severe symptoms, the relation between consumption of caffeine-containing beverages and premenstrual syndrome was dose-dependent, with prevalence odds ratios equal to 1.3 for consumers of one cup of a caffeine-containing beverage per day and increasing steadily to 7.0 for consumers of eight to 10 cups per day. The effects were apparent among both caffeine-containing tea/coffee consumers and caffeine-containing soda consumers. The observed effects were only slightly reduced when daily total fluid consumption was controlled. Daily total fluid consumption also was related to the prevalence of premenstrual symptoms although the effects were large only for consumers of 13-19 cups of fluid per day (the largest amount studied).

Retention performance of green roofs in three different climate regions

NASA Astrophysics Data System (ADS)

Sims, Andrew W.; Robinson, Clare E.; Smart, Charles C.; Voogt, James A.; Hay, Geoffrey J.; Lundholm, Jeremey T.; Powers, Brandon; O'Carroll, Denis M.

2016-11-01

Green roofs are becoming increasingly popular for moderating stormwater runoff in urban areas. This study investigated the impact different climates have on the retention performance of identical green roofs installed in London Ontario (humid continental), Calgary Alberta (semi-arid, continental), and Halifax Nova Scotia (humid, maritime). Drier climates were found to have greater percent cumulative stormwater retention with Calgary (67%) having significantly better percent retention than both London (48%) and Halifax (34%). However, over the same study period the green roof in London retained the greatest depth of stormwater (598 mm), followed by the green roof in Halifax (471 mm) and then Calgary (411 mm). The impact of climate was largest for medium sized storms where the antecedent moisture condition (AMC) at the beginning of a rainfall event governs retention performance. Importantly AMC was a very good predictor of stormwater retention, with similar retention at all three sites for a given AMC, emphasizing that AMC is a relevant indicator of retention performance in any climate. For large rainfall events (i.e., >45 mm) green roof average retention ranged between 16% and 29% in all cities. Overall, drier climates have superior retention due to lower AMC in the media. However, moderate and wet climates still provide substantial total volume reduction benefits.

Fluids in crustal deformation: Fluid flow, fluid-rock interactions, rheology, melting and resources

NASA Astrophysics Data System (ADS)

Lacombe, Olivier; Rolland, Yann

2016-11-01

Fluids exert a first-order control on the structural, petrological and rheological evolution of the continental crust. Fluids interact with rocks from the earliest stages of sedimentation and diagenesis in basins until these rocks are deformed and/or buried and metamorphosed in orogens, then possibly exhumed. Fluid-rock interactions lead to the evolution of rock physical properties and rock strength. Fractures and faults are preferred pathways for fluids, and in turn physical and chemical interactions between fluid flow and tectonic structures, such as fault zones, strongly influence the mechanical behaviour of the crust at different space and time scales. Fluid (over)pressure is associated with a variety of geological phenomena, such as seismic cycle in various P-T conditions, hydrofracturing (including formation of sub-horizontal, bedding-parallel veins), fault (re)activation or gravitational sliding of rocks, among others. Fluid (over)pressure is a governing factor for the evolution of permeability and porosity of rocks and controls the generation, maturation and migration of economic fluids like hydrocarbons or ore forming hydrothermal fluids, and is therefore a key parameter in reservoir studies and basin modeling. Fluids may also help the crust partially melt, and in turn the resulting melt may dramatically change the rheology of the crust.

Gone fishing in a fluid trial.

PubMed

Hjortrup, Peter B; Haase, Nicolai; Wetterslev, Jørn; Perner, Anders

2016-03-01

To maximise the yield of existing data by assessing the effect on mortality of being born under the zodiac sign Pisces in a trial of intravenous (IV) fluids. A retrospective observational study, with no predefined hypothesis or statistical analysis plan, of 26 Scandinavian intensive care units between 2009 and 2011. Patients aged 18 years or older with severe sepsis and in need of fluid resuscitation, randomised in the Scandinavian Starch for Severe Sepsis/ Septic Shock (6S) trial. Ninety-day mortality. We included all 798 randomised patients in our study; 70 (9%) were born under the sign of Pisces. The primary outcome (death within 90 days after randomisation) occurred in 25 patients (35.7%) in the Pisces group, compared with 348 patients (48%) in the non-Pisces group (relative risk, 0.75; 95% CI, 0.54-1.03; one-sided P = 0.03). In a multicentre randomised clinical trial of IV fluids, being born under the sign of Pisces was associated with a decreased risk of death. Our study shows that with convenient use of statistics and an enticing explanatory hypothesis, it is possible to achieve significant findings in post-hoc analyses of data from large trials.

Evaluation of an amide-based stationary phase for supercritical fluid chromatography

PubMed Central

Borges-Muñoz, Amaris C.; Colón, Luis A.

2017-01-01

A relatively new stationary phase containing a polar group embedded in a hydrophobic backbone (i.e., ACE® C18-amide) was evaluated for use in supercritical fluid chromatography. The amide-based column was compared with columns packed with bare silica, C18 silica, and a terminal-amide silica phase. The system was held at supercritical pressure and temperature with a mobile phase composition of CO2 and methanol as cosolvent. The linear solvation energy relationship model was used to evaluate the behavior of these stationary phases, relating the retention factor of selected probes to specific chromatographic interactions. A five-component test mixture, consisting of a group of drug-like molecules was separated isocratically. The results show that the C18-amide stationary phase provided a combination of interactions contributing to the retention of the probe compounds. The hydrophobic interactions are favorable; however, the electron donating ability of the embedded amide group shows a large positive interaction. Under the chromatographic conditions used, the C18-amide column was able to provide baseline resolution of all the drug-like probe compounds in a text mixture, while the other columns tested did not. PMID:27396487

Herpes zoster-induced acute urinary retention.

PubMed

Addison, Ben; Harvey, Martyn

2013-06-01

Urinary retention is a common acute presentation for men in their later decades. Potential contributing pathologies are numerous. We report an unusual case of acute urinary retention requiring catheterisation secondary to sacral herpes zoster reactivation (S2-4) in an 88-year-old man with minimal preceding obstructive symptoms. © 2013 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

Natural frequency and stability analysis of a pipe conveying fluid with axially moving supports immersed in fluid

NASA Astrophysics Data System (ADS)

Ni, Qiao; Luo, Yangyang; Li, Mingwu; Yan, Hao

2017-09-01

Structural model for a slender and uniform pipe conveying fluid, with axially moving supports on both ends, immersed in an incompressible fluid, is formulated. Free vibration and stability of the system are studied through numerical calculation. First, the equations of motion of the system are derived in an absolute coordinate system. An "axial added mass coefficient" is adopted to amend the forces caused by the external fluid. Boundary conditions are fixed by using coordinated conversion. Then, numerical results of the natural frequency are obtained via the Galerkin method, both for pinned-pinned and clamped-clamped supports. The critical speeds of supports and several instability types are discussed. Last, the effects of the system parameters on the dynamics and instability of the system are investigated.

Strategies to improve retention in randomised trials

PubMed Central

Brueton, Valerie C; Tierney, Jayne; Stenning, Sally; Harding, Seeromanie; Meredith, Sarah; Nazareth, Irwin; Rait, Greta

2013-01-01

severe symptoms do not return questionnaires or attend a follow-up visit, this will bias the findings of the trial. Many methods are used by researchers to keep people in trials. These encourage people to send back data by questionnaire, return to a clinic or hospital for trial-related tests, or be seen by a health or community care worker. Study characteristics This review identified methods that encouraged people to stay in trials. We searched scientific databases for randomised studies (where people are allocated to one of two or more possible treatments in a random manner) or quasi-randomised studies (where allocation is not really random, e.g. based on date of birth, order in which they attended clinic) that compared methods of increasing retention in trials. We included trials of participants from any age, gender, ethnic, cultural, language and geographic groups. Key results The methods that appeared to work were offering or giving a small amount of money for return of a completed questionnaire and enclosing a small amount of money with a questionnaire with the promise of a further small amount of money for return of a filled in questionnaire. The effect of other ways to keep people in trials is still not clear and more research is needed to see if these really do work. Such methods are shorter questionnaires, sending questionnaires by recorded delivery, using a trial design where people know which treatment they will receive, sending specially designed letters with a reply self addressed stamped envelope followed by a number of reminders, offering a donation to charity or entry into a prize draw, sending a reminder to the study site about participants to follow-up, sending questionnaires close to the time the patient was last followed-up, managing peoples' follow-up, conducting follow-up by telephone and changing the order of questionnaire questions. Quality of evidence The methods that we identified were tested in trials run in many different disease areas and

Analysis of DNA Methylation Status in Bodily Fluids for Early Detection of Cancer

PubMed Central

Yokoi, Keigo; Yamashita, Keishi; Watanabe, Masahiko

2017-01-01

Epigenetic alterations by promoter DNA hypermethylation and gene silencing in cancer have been reported over the past few decades. DNA hypermethylation has great potential to serve as a screening marker, a prognostic marker, and a therapeutic surveillance marker in cancer clinics. Some bodily fluids, such as stool or urine, were obtainable without any invasion to the body. Thus, such bodily fluids were suitable samples for high throughput cancer surveillance. Analyzing the methylation status of bodily fluids around the cancer tissue may, additionally, lead to the early detection of cancer, because several genes in cancer tissues are reported to be cancer-specifically hypermethylated. Recently, several studies that analyzed the methylation status of DNA in bodily fluids were conducted, and some of the results have potential for future development and further clinical use. In fact, a stool DNA test was approved by the U.S. Food and Drug Administration (FDA) for the screening of colorectal cancer. Another promising methylation marker has been identified in various bodily fluids for several cancers. We reviewed studies that analyzed DNA methylation in bodily fluids as a less-invasive cancer screening. PMID:28358330

Supercritical fluid extraction and direct fluid injection mass spectrometry for the determination of trichothecene mycotoxins in wheat samples

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kalinoski, H.T.; Udseth, H.R.; Wright, B.W.

1986-10-01

The application of on-line supercritical fluid extraction with chemical ionization mass spectrometry and collision induced dissociation tandem mass spectrometry for the rapid identification of parts-per-million levels of several trichothecene mycotoxins is demonstrated. Supercritical carbon dioxide is shown to allow identification of mycotoxins with minimum sample handling in complex natural matrices (e.g., wheat). Tandem mass spectrometry techniques are employed for unambiguous identification of compounds of varying polarity, and false positives from isobaric compounds are avoided. Capillary column supercritical fluid chromatography-mass spectrometry of a supercritical fluid extract of the same sample was also performed and detection limits in the parts-per-billion range appearmore » feasible.« less

Retention strategies in longitudinal studies with emerging adults.

PubMed

Hanna, Kathleen M; Scott, Linda L; Schmidt, Karen K

2014-01-01

The purpose of this report was to describe retention strategies that were useful and those that were not in a longitudinal study of emerging adults. A longitudinal study examining the transition to young adulthood among emerging adults with type 1 diabetes, which had success in retention, provided the context for describing retention strategies. A challenge in longitudinally designed studies is retention of participants because the loss decreases power for statistical analysis. Given that emerging adulthood is a period of instability, retention is particularly challenging among this population. However, longitudinal studies are the best way to understand developmental changes, and it is also important to increase our knowledge of health outcomes during emerging adulthood. Retention strategies used in the study are described, including promoting a positive relationship with participants, maintaining contact with participants, having a study staff with good interpersonal skills, using incentives, conveying respect for participants, and using user-friendly data collection. Useful strategies to promote a positive relationship included sending cards and newsletters to participants, maintaining consistency of contact person, and expressing appreciation for participant's time and effort. Useful strategies for maintaining contact with participants included obtaining contact information at every data collection point, maintaining birth dates and chart numbers in tracking databases, monitoring returned mail, and using Web search engines. Other useful strategies were providing incentives to participants, employing staff with good interpersonal skills, providing participants with choices when appropriate, and using user-friendly data collection. One strategy, using contests, was not found useful. Despite the challenges of conducting longitudinally designed studies with emerging adults, multiple retention strategies can be used that are useful to retention. It is feasible to

Dexamethasone Injection

MedlinePlus

... severe allergic reactions. It is used in the management of certain types of edema (fluid retention and ... needed for normal body functioning) and in the management of certain types of shock. Dexamethasone injection is ...

5 CFR 351.401 - Determining retention standing.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 5 Administrative Personnel 1 2012-01-01 2012-01-01 false Determining retention standing. 351.401 Section 351.401 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS REDUCTION IN FORCE Scope of Competition § 351.401 Determining retention standing. Each agency shall...

5 CFR 351.401 - Determining retention standing.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Determining retention standing. 351.401 Section 351.401 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS REDUCTION IN FORCE Scope of Competition § 351.401 Determining retention standing. Each agency shall...

5 CFR 351.401 - Determining retention standing.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 5 Administrative Personnel 1 2014-01-01 2014-01-01 false Determining retention standing. 351.401 Section 351.401 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS REDUCTION IN FORCE Scope of Competition § 351.401 Determining retention standing. Each agency shall...

5 CFR 351.401 - Determining retention standing.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 5 Administrative Personnel 1 2013-01-01 2013-01-01 false Determining retention standing. 351.401 Section 351.401 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS REDUCTION IN FORCE Scope of Competition § 351.401 Determining retention standing. Each agency shall...

5 CFR 351.401 - Determining retention standing.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Determining retention standing. 351.401 Section 351.401 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS REDUCTION IN FORCE Scope of Competition § 351.401 Determining retention standing. Each agency shall...

Can retention forestry help conserve biodiversity? A meta-analysis

PubMed Central

Fedrowitz, Katja; Koricheva, Julia; Baker, Susan C; Lindenmayer, David B; Palik, Brian; Rosenvald, Raul; Beese, William; Franklin, Jerry F; Kouki, Jari; Macdonald, Ellen; Messier, Christian; Sverdrup-Thygeson, Anne; Gustafsson, Lena

2014-01-01

Industrial forestry typically leads to a simplified forest structure and altered species composition. Retention of trees at harvest was introduced about 25 years ago to mitigate negative impacts on biodiversity, mainly from clearcutting, and is now widely practiced in boreal and temperate regions. Despite numerous studies on response of flora and fauna to retention, no comprehensive review has summarized its effects on biodiversity in comparison to clearcuts as well as un-harvested forests. Using a systematic review protocol, we completed a meta-analysis of 78 studies including 944 comparisons of biodiversity between retention cuts and either clearcuts or un-harvested forests, with the main objective of assessing whether retention forestry helps, at least in the short term, to moderate the negative effects of clearcutting on flora and fauna. Retention cuts supported higher richness and a greater abundance of forest species than clearcuts as well as higher richness and abundance of open-habitat species than un-harvested forests. For all species taken together (i.e. forest species, open-habitat species, generalist species and unclassified species), richness was higher in retention cuts than in clearcuts. Retention cuts had negative impacts on some species compared to un-harvested forest, indicating that certain forest-interior species may not survive in retention cuts. Similarly, retention cuts were less suitable for some open-habitat species compared with clearcuts. Positive effects of retention cuts on richness of forest species increased with proportion of retained trees and time since harvest, but there were not enough data to analyse possible threshold effects, that is, levels at which effects on biodiversity diminish. Spatial arrangement of the trees (aggregated vs. dispersed) had no effect on either forest species or open-habitat species, although limited data may have hindered our capacity to identify responses. Results for different comparisons were largely

Can retention forestry help conserve biodiversity? A meta-analysis.

PubMed

Fedrowitz, Katja; Koricheva, Julia; Baker, Susan C; Lindenmayer, David B; Palik, Brian; Rosenvald, Raul; Beese, William; Franklin, Jerry F; Kouki, Jari; Macdonald, Ellen; Messier, Christian; Sverdrup-Thygeson, Anne; Gustafsson, Lena

2014-12-01

Industrial forestry typically leads to a simplified forest structure and altered species composition. Retention of trees at harvest was introduced about 25 years ago to mitigate negative impacts on biodiversity, mainly from clearcutting, and is now widely practiced in boreal and temperate regions. Despite numerous studies on response of flora and fauna to retention, no comprehensive review has summarized its effects on biodiversity in comparison to clearcuts as well as un-harvested forests. Using a systematic review protocol, we completed a meta-analysis of 78 studies including 944 comparisons of biodiversity between retention cuts and either clearcuts or un-harvested forests, with the main objective of assessing whether retention forestry helps, at least in the short term, to moderate the negative effects of clearcutting on flora and fauna. Retention cuts supported higher richness and a greater abundance of forest species than clearcuts as well as higher richness and abundance of open-habitat species than un-harvested forests. For all species taken together (i.e. forest species, open-habitat species, generalist species and unclassified species), richness was higher in retention cuts than in clearcuts. Retention cuts had negative impacts on some species compared to un-harvested forest, indicating that certain forest-interior species may not survive in retention cuts. Similarly, retention cuts were less suitable for some open-habitat species compared with clearcuts. Positive effects of retention cuts on richness of forest species increased with proportion of retained trees and time since harvest, but there were not enough data to analyse possible threshold effects, that is, levels at which effects on biodiversity diminish. Spatial arrangement of the trees (aggregated vs. dispersed) had no effect on either forest species or open-habitat species, although limited data may have hindered our capacity to identify responses. Results for different comparisons were largely