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Sample records for high abdominal pressure

  1. Association between general and abdominal obesity with high blood pressure: difference between genders

    Directory of Open Access Journals (Sweden)

    Alison O. Silva

    2016-04-01

    Full Text Available Abstract Objective: To assess the association between general and abdominal obesity with high blood pressure in adolescents of both genders from the public school system. Methods: This was an epidemiological, descriptive, exploratory study, with a quantitative approach and local scope whose sample consisted of 481 high school students (aged 14–19, selected by using a random cluster sampling strategy. Blood pressure was measured through the use of automated monitor and was considered high when the pressure values were at or above the 95th percentile. The analyses were performed using the chi-squared test and binary logistic regression. Results: The prevalence of high blood pressure was 6.4%, and it was higher among boys (9.0% vs. 4.7%, p < 0.05. There was no significant difference between general (p = 0.903 and abdominal obesity (p = 0.157 when genders were compared. After adjusting for age, high blood pressure was associated with general (OR = 6.4; p < 0.001 and abdominal obesity (OR = 7.0; p < 0.001 only among boys, when comparing the fourth quartile with the first quartile of body mass index (≤18.6 kg/m2 vs. ≥23.5 kg/m2 and waist circumference (≤69 cm vs. ≥80.1 cm. Conclusion: It was observed that general and abdominal obesity are associated with high blood pressure only in boys, regardless of age.

  2. Intra-abdominal pressure during swimming.

    Science.gov (United States)

    Moriyama, S; Ogita, F; Huang, Z; Kurobe, K; Nagira, A; Tanaka, T; Takahashi, H; Hirano, Y

    2014-02-01

    The present study aimed to determine the intra-abdominal pressure during front crawl swimming at different velocities in competitive swimmers and to clarify the relationships between stroke indices and changes in intra-abdominal pressure. The subjects were 7 highly trained competitive collegiate male swimmers. Intra-abdominal pressure was measured during front crawl swimming at 1.0, 1.2 and 1.4 m · s(-1) and during the Valsalva maneuver. Intra-abdominal pressure was taken as the difference between minimum and maximum values, and the mean of 6 stable front crawl stroke cycles was used. Stroke rate and stroke length were also measured as stroke indices. There were significant differences in stroke rate among all velocities (P swimming velocity. These findings do not appear to support the effectiveness of trunk training performed by competitive swimmers aimed at increasing intra-abdominal pressure. © Georg Thieme Verlag KG Stuttgart · New York.

  3. Negative pressure device for intra-abdominal pressure reduction

    Energy Technology Data Exchange (ETDEWEB)

    David, M; Geido, D; Pracca, F; Sanchez, G; Simini, F; Zoppolo, C [Nucleo de Ingenierfa Biomedica, Universidad de la Republica O. del Uruguay, Hospital de ClInicas, Av. Italia S/N, 11600, Montevideo (Uruguay)

    2007-11-15

    A device that generates negative extra-abdominal pressure (ABDOPRE) for treatment of patients with high intra-abdominal pressure was developed. It includes pressure sensors for transducing intra-abdominal pressure through an intra-vesical catheter and negative pressure in the vacuum bell which is placed over the abdomen. By means of a control system, a pattern for reducing IAP is set, according to a clinical protocol. The external negative pressure is generated using a vacuum pump connected to the bell. The system registers the values of interest for the medical history. The system is being tested over ICU patients, registering a satisfactory IAP reduction.

  4. Visceral adiposity, not abdominal subcutaneous fat area, is associated with high blood pressure in Japanese men: the Ohtori study.

    Science.gov (United States)

    Koh, Hideo; Hayashi, Tomoshige; Sato, Kyoko Kogawa; Harita, Nobuko; Maeda, Isseki; Nishizawa, Yoshiki; Endo, Ginji; Fujimoto, Wilfred Y; Boyko, Edward J; Hikita, Yonezo

    2011-05-01

    Visceral adiposity is considered to have a key role in cardiometabolic diseases. The purpose of this study is to investigate cross-sectionally the association between intra-abdominal fat area (IAFA) measured by computed tomography (CT) and high blood pressure independent of abdominal subcutaneous fat area (ASFA) and insulin resistance. Study participants included 624 Japanese men not taking oral hypoglycemic medications or insulin. Abdominal, thoracic and thigh fat areas were measured by CT. Total fat area (TFA) was calculated as the sum of abdominal, thoracic and thigh fat area. Total subcutaneous fat area (TSFA) was defined as TFA minus IAFA. Hypertension and high normal blood pressure were defined using the 1999 criteria of the World Health Organization. Multiple-adjusted odds ratios of hypertension for tertiles of IAFA were 2.64 (95% confidence interval, 1.35-5.16) for tertile 2, and 5.08 (2.48-10.39) for tertile 3, compared with tertile 1 after adjusting for age, fasting immunoreactive insulin, diabetes status, ASFA, alcohol consumption, regular physical exercise and smoking habit. IAFA remained significantly associated with hypertension even after adjustment for ASFA, TSFA, TFA, body mass index or waist circumference, and no other measure of regional or total adiposity was associated with the odds of hypertension in models, which included IAFA. Similar results were obtained for the association between IAFA and the prevalence of high normal blood pressure or hypertension. In conclusion, greater visceral adiposity was associated with a higher odds of high blood pressure in Japanese men.

  5. [Monitoring of intra-abdominal pressure and abdominal perfusion pressure in urgent abdominal surgery].

    Science.gov (United States)

    Raĭbuzhis, E N; Fot, E V; Gaĭdukov, K M; Kirov, M Iu

    2014-01-01

    To evaluate the changes in intra-abdominal pressure (IAP) and abdominal perfusion pressure (APP) during perioperative period in urgent abdominal surgery and to assess the relationship of these parameters with gas exchange and tissue perfusion. Twenty-four patients undergoing emergency abdominal surgery were enrolled into a prospective observational study. We recorded IAP APP, mean arterial pressure, arterial and venous blood gases after induction of anesthesia, at the end of surgery, and 6, 12, 48 and 72 h postoperatively. LAP was measured by nasogastric tube using CiMON monitor (Pulsion Medical Systems, Germany). In addition, we studied the relationship of IAP and APP with blood gases parameters. We observed perioperative increase of IAP (> 12 mm Hg) in 75% of enrolled patients, tendency to postoperative rise of IAP and transient increase of arterial lactate at 6 h after surgery. APP remained within normal values. We found positive correlation of APP with PaO2/FiO2 and ScvO2 at 72 hours after surgery. Transient perioperative increase of IAP was observed in 75% patients undergoing urgent abdominal surgery; however in parallel with intensive care the abdominal perfusion pressure remained within normal values. Abdominal perfusion is related with arterial oxygenation and central venous saturation.

  6. abdominal pressure monitoring in varying intra- abdominal ...

    African Journals Online (AJOL)

    TV measurements were achieved using a manual manometer system with a Foley ... relatedness. As the test subjects were organised into related groups, we used intra- .... air before instillation of fluid, contractility of the muscular stomach wall, an exit ... TV techniques both have utility in the clinical setting, with TG pressure.

  7. Effects of ovariohysterectomy on intra-abdominal pressure and abdominal perfusion pressure in cats.

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    Bosch, L; Rivera del Álamo, M M; Andaluz, A; Monreal, L; Torrente, C; García-Arnas, F; Fresno, L

    2012-12-15

    Intra-abdominal pressure (IAP) and abdominal perfusion pressure (APP) have shown clinical relevance in monitoring critically ill human beings submitted to abdominal surgery. Only a few studies have been performed in veterinary medicine. The aim of this study was to assess how pregnancy and abdominal surgery may affect IAP and APP in healthy cats. For this purpose, pregnant (n=10) and non-pregnant (n=11) queens undergoing elective spaying, and tomcats (n=20, used as controls) presented for neutering by scrotal orchidectomy were included in the study. IAP, mean arterial blood pressure (MAP), APP, heart rate and rectal temperature (RT) were determined before, immediately after, and four hours after surgery. IAP increased significantly immediately after abdominal surgery in both female groups when compared with baseline (PPregnancy did not seem to affect IAP in this population of cats, possibly due to subjects being in early stages of pregnancy.

  8. Intra-abdominal pressure: an integrative review.

    Science.gov (United States)

    Milanesi, Rafaela; Caregnato, Rita Catalina Aquino

    2016-01-01

    There is a growing request for measuring intra-abdominal pressure in critically ill patients with acute abdominal pain to be clarified. Summarizing the research results on measurement of vesical intra-abdominal pressure and analyzing the level of evidence were the purposes of this integrative literature review, carried out based on the databases LILACS, MEDLINE and PubMed, from 2005 to July 2012. Twenty articles were identified, in that, 12 literature reviews, 4 descriptive and exploratory studies, 2 expert opinions, one prospective cohort study and one was an experience report. The vesical intra-abdominal pressure measurement was considered gold standard. There are variations in the technique however, but some common points were identified: complete supine position, in absence of abdominal contracture, in the end of expiration and expressed in mmHg. Most research results indicate keeping the transducer zeroed at the level of the mid-axillary line at the iliac crest level, and instill 25mL of sterile saline. Strong evidence must be developed. RESUMO Em pacientes críticos com quadros abdominais agudos a esclarecer é crescente a solicitação da aferição da pressão intra-abdominal. Sintetizar resultados de pesquisas sobre a mensuração da pressão intra-abdominal pela via vesical e analisar o nível de evidência foram os objetivos desta revisão integrativa da literatura, realizada nas bases LILACS, MEDLINE e PubMed, no período de 2005 a julho de 2012. Identificaram-se 20 artigos, sendo 12 revisões de literatura, 4 estudos exploratório-descritivos, 2 opiniões de especialistas, 1 estudo de coorte prospectivo e 1 relato de experiência. O método vesical para mensuração da pressão intra-abdominal foi considerado padrão-ouro. Existem variações na técnica, entretanto pontos em comum foram identificados: posição supina completa, na ausência de contratura abdominal, ao final da expiração e expressa em mmHg. A maioria indica posicionar o ponto zero do

  9. [Changes of the intraabdominal pressure in patients with abdominal sepsis].

    Science.gov (United States)

    Kursov, S V

    2013-01-01

    64 patients with abdominal sepsis were included in the study of the intraabdominal pressure changes before and after the operation. The study demonstrated that the use of the crystalloids alone leads to the development of the capillary leak syndrome in comparison with the therapy regimen using colloids. The aggressive fluid resuscitation, associated with high numbers of central venous pressure, increasing 1177Pa (120 mm H2O), was connected with the increase of the intraabdominal pressure.

  10. The Diagnostic Value of Intra-abdominal Pressure in Patients with Blunt Acute Abdominal Trauma

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    Huseyin Narci

    2012-06-01

    Full Text Available Purpose:The objective of this study was to determine the diagnostic value of intra-abdominal pressure measurement in blunt abdominal trauma patients. Method: A prospective study was performed in 49 patients with blunt trauma in our university hospital for 1 years. Patients were randomly into two groups as intra-abdominal trauma (n=28 and extraabdominal trauma (n=21 groups. Intra-abdominal pressures was measured an classified as normal (10 cm H2O or less, elevated (more than 10 cm H2O determined indirectly. Results: No significant differences were found between abdominal trauma and extra-abdominal trauma groups from the point of intra-abdominal pressure (IAP. One the other hand, in abdominal trauma group; significant differences were observed between operated patients. Intra-abdominal bleeding was found in 10 patients and all of them elevated IAP values (exceeding 16 cm H2O. For determining the intra-abdominal injury, IAP had a sensitivity of 93%, specificity 38% in patients. Conclusion: IAP exceeding 16 cm H2O with blunt abdominal trauma patients abdominal trauma can be detected. It is thought that IAP, indirect monitoring of abdominal trauma patients is a reproducible, scientific guide and simple method.To determine the efficacy of the measurement of intra-abdominal pressure in blunt abdominal trauma patients, further studies should be done. [Cukurova Med J 2012; 37(3.000: 157-161

  11. The potential participation of abdominal pressure in preeclampsia.

    Science.gov (United States)

    Zhang, Andy K

    2015-06-01

    Preeclampsia is a major cause of maternal and perinatal mortality and morbidity. Regardless of susceptibility or predisposing conditions and risk factors, the degree of increase in abdominal pressure is directly related to the severity of preeclampsia, particularly in women with hydatidiform mole. When increased abdominal pressure is normalized by delivery, preeclampsia is cured. Recent genetic studies highlighted two leading risk factors for preeclampsia: chronic renal disease and T235 homozygosity for the AGT gene. Thus, while there is increased abdominal pressure in pregnancy, an imbalanced renin angiotensin system and renal injuries lead to a vicious cycle of increasing abdominal pressure and further renal injuries. A hypothesis for the potential participation of pressure in preeclampsia is described and the amelioration of preeclampsia through postural intervention and the possible therapeutic effect of angiotensin is suggested.

  12. A Single-Lumen Central Venous Catheter for Continuous and Direct Intra-abdominal Pressure Measurement

    NARCIS (Netherlands)

    O.J.F. van Waes (Oscar); J.B. Jaquet (Jean); W.C.J. Hop (Wim); M.J.M. Morak (Marjolein); J.N.M. IJzermans (Jan); J. Koning (Jan)

    2009-01-01

    textabstractBackground: Abdominal compartment syndrome (ACS) is associated with high morbidity and mortality rates. Therefore, the need for a good diagnostic tool to predict intra-abdominal hypertension (IAH) and progression to ACS is paramount. Bladder pressure (BP) has been used for several years

  13. Detecção de hipertensão arterial em adolescentes através de marcadores gerais e adiposidade abdominal Detección de hipertensión arterial en adolescentes por medio de marcadores generales y adiposidad abdominal High blood pressure detection in adolescents by clustering overall and abdominal adiposity markers

    Directory of Open Access Journals (Sweden)

    Diego G. D Christofaro

    2011-06-01

    Full Text Available FUNDAMENTO: A obesidade está ligada à hipertensão arterial (HA na infância. Entretanto, o papel da gordura como preditor de HA em adolescentes permanece desconhecido. OBJETIVO: Investigar a associação entre obesidade geral e abdominal com HA e identificar a sensibilidade e especificidade desses indicadores para detectar HA em adolescentes. MÉTODOS: A amostra consistiu em 1.021 adolescentes com idade de 10-17 anos. Os indivíduos foram classificados como normal, sobrepeso/obesidade, de acordo com as medidas do IMC, e como não-obeso com obesidade abdominal, de acordo com as medidas da circunferência da cintura (CC. A pressão arterial sistólica (PAS e diastólica (PAD foi avaliada através de um dispositivo oscilométrico. Regressão logística e curvas ROC foram usadas na análise estatística. RESULTADOS: A prevalência geral de HA foi 11,8% (13,4% em meninos e 10,2% em meninas. A prevalência de HA em meninos e meninas com sobrepeso/obesidade foi 10% e 11,1%, respectivamente. A prevalência de HA em meninos com obesidade abdominal foi 28,6%. Para ambos os sexos, o odds ratio (OR para HA foi mais alto na obesidade abdominal do que no sobrepeso/obesidade geral (4,09 [OR IC95% = 2,57-6,51] versus 1,83 [OR IC95% = 1,83-4,30]. O OR para HA foi mais alto quando sobrepeso/obesidade geral e obesidade abdominal estavam agrupados (OR = 4,35 [OR IC95% = 2,68 -7,05], do que quando identificados como sobrepeso/obesidade geral ou obesidade abdominal apenas (OR = 1,32 [OR IC95% = 0,65- 2,68]. Entretanto, ambos os tipos de obesidade apresentavam baixo poder preditivo na detecção de HA. CONCLUSÃO: Obesidade geral e obesidade abdominal foram associadas com HA; entretanto, a sensibilidade e especificidade dessas variáveis na detecção de HA são baixas em adolescentes brasileiros.BACKGROUND: Obesity is linked to high blood pressure (HBP in childhood. However, the role of fat as a predictor of HBP in adolescents remains unknown. OBJECTIVE: To

  14. Wireless system for monitoring Intra-abdominal pressure in patient with severe abdominal pathology

    Science.gov (United States)

    Sokolovskiy, S. S.; Shtotskiy, Y. V.; Leljanov, A. D.

    2017-01-01

    The paper discusses an experimental design of the wireless system for monitoring intra-abdominal pressure (IAP) using Bluetooth Low Energy technology. The possibility of measuring IAP via the bladder using a wireless pressure sensor with a hydrophobic bacteria filter between the liquid transmitting medium and the sensor element is grounded.

  15. Pressure Measurement Techniques for Abdominal Hypertension: Conclusions from an Experimental Model

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    Sascha Santosh Chopra

    2015-01-01

    Full Text Available Introduction. Intra-abdominal pressure (IAP measurement is an indispensable tool for the diagnosis of abdominal hypertension. Different techniques have been described in the literature and applied in the clinical setting. Methods. A porcine model was created to simulate an abdominal compartment syndrome ranging from baseline IAP to 30 mmHg. Three different measurement techniques were applied, comprising telemetric piezoresistive probes at two different sites (epigastric and pelvic for direct pressure measurement and intragastric and intravesical probes for indirect measurement. Results. The mean difference between the invasive IAP measurements using telemetric pressure probes and the IVP measurements was −0.58 mmHg. The bias between the invasive IAP measurements and the IGP measurements was 3.8 mmHg. Compared to the realistic results of the intraperitoneal and intravesical measurements, the intragastric data showed a strong tendency towards decreased values. The hydrostatic character of the IAP was eliminated at high-pressure levels. Conclusion. We conclude that intragastric pressure measurement is potentially hazardous and might lead to inaccurately low intra-abdominal pressure values. This may result in missed diagnosis of elevated abdominal pressure or even ACS. The intravesical measurements showed the most accurate values during baseline pressure and both high-pressure plateaus.

  16. Interaction between intra-abdominal pressure and positive-end expiratory pressure

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    Jamili Anbar Torquato

    2009-02-01

    Full Text Available OBJECTIVE: The aim of this study was to quantify the interaction between increased intra-abdominal pressure and Positive-End Expiratory Pressure. METHODS: In 30 mechanically ventilated ICU patients with a fixed tidal volume, respiratory system plateau and abdominal pressure were measured at a Positive-End Expiratory Pressure level of zero and 10 cm H2O. The measurements were repeated after placing a 5 kg weight on the patients' belly. RESULTS: After the addition of 5 kg to the patients' belly at zero Positive-End Expiratory Pressure, both intra-abdominal pressure (p<0.001 and plateau pressures (p=0.005 increased significantly. Increasing the Positive-End Expiratory Pressure levels from zero to 10 cm H2O without weight on the belly did not result in any increase in intra-abdominal pressure (p=0.165. However, plateau pressures increased significantly (p< 0.001. Increasing Positive-End Expiratory Pressure from zero to 10 cm H2O and adding 5 kg to the belly increased intra-abdominal pressure from 8.7 to 16.8 (p<0.001 and plateau pressure from 18.26 to 27.2 (p<0.001. Maintaining Positive-End Expiratory Pressure at 10 cm H2O and placing 5 kg on the belly increased intra-abdominal pressure from 12.3 +/- 1.7 to 16.8 +/- 1.7 (p<0.001 but did not increase plateau pressure (26.6+/-1.2 to 27.2 +/-1.1 -p=0.83. CONCLUSIONS: The addition of a 5kg weight onto the abdomen significantly increased both IAP and the airway plateau pressure, confirming that intra-abdominal hypertension elevates the plateau pressure. However, plateau pressure alone cannot be considered a good indicator for the detection of elevated intra-abdominal pressure in patients under mechanical ventilation using PEEP. In these patients, the intra-abdominal pressure must also be measured.

  17. Intra-abdominal pressure and abdominal compartment syndrome in acute general surgery.

    LENUS (Irish Health Repository)

    Sugrue, Michael

    2012-01-31

    BACKGROUND: Intra-abdominal pressure (IAP) is a harbinger of intra-abdominal mischief, and its measurement is cheap, simple to perform, and reproducible. Intra-abdominal hypertension (IAH), especially grades 3 and 4 (IAP > 18 mmHg), occurs in over a third of patients and is associated with an increase in intra-abdominal sepsis, bleeding, renal failure, and death. PATIENTS AND METHODS: Increased IAP reading may provide an objective bedside stimulus for surgeons to expedite diagnostic and therapeutic work-up of critically ill patients. One of the greatest challenges surgeons and intensivists face worldwide is lack of recognition of the known association between IAH, ACS, and intra-abdominal sepsis. This lack of awareness of IAH and its progression to ACS may delay timely intervention and contribute to excessive patient resuscitation. CONCLUSIONS: All patients entering the intensive care unit (ICU) after emergency general surgery or massive fluid resuscitation should have an IAP measurement performed every 6 h. Each ICU should have guidelines relating to techniques of IAP measurement and an algorithm for management of IAH.

  18. Abdominal drainage following cholecystectomy: high, low, or no suction?

    OpenAIRE

    McCormack, T T; Abel, P D; Collins, C. D.

    1983-01-01

    A prospective trial to assess the effect of suction in an abdominal drain following cholecystectomy was carried out. Three types of closed drainage system were compared: a simple tube drain, a low negative pressure drain, and a high negative pressure drain: 120 consecutive patients undergoing cholecystectomy were randomly allocated to one of the three drainage groups. There was no significant difference in postoperative pyrexia, wound infection, chest infection, or hospital stay. This study f...

  19. Atmospheric pressure variations and abdominal aortic aneurysm rupture.

    LENUS (Irish Health Repository)

    Killeen, S D

    2012-02-03

    BACKGROUND: Ruptured abdominal aortic aneurysm (RAAA) presents with increased frequency in the winter and spring months. Seasonal changes in atmospheric pressure mirrors this pattern. AIM: To establish if there was a seasonal variation in the occurrence of RAAA and to determine if there was any association with atmospheric pressure changes. METHODS: A retrospective cohort-based study was performed. Daily atmospheric pressure readings for the region were obtained. RESULTS: There was a statistically significant monthly variation in RAAA presentation with 107 cases (52.5%) occurring from November to March. The monthly number of RAAA and the mean atmospheric pressure in the previous month were inversely related (r = -0.752, r (2) = 0.566, P = 0.03), and there was significantly greater daily atmospheric pressure variability on days when patients with RAAA were admitted. CONCLUSION: These findings suggest a relationship between atmospheric pressure and RAAA.

  20. Hypertension (High Blood Pressure)

    Science.gov (United States)

    ... Surgery? A Week of Healthy Breakfasts Shyness Hypertension (High Blood Pressure) KidsHealth > For Teens > Hypertension (High Blood Pressure) Print ... rest temperature diet emotions posture medicines Why Is High Blood Pressure Bad? High blood pressure means a person's heart ...

  1. A user's guide to intra-abdominal pressure measurement.

    LENUS (Irish Health Repository)

    Sugrue, Michael

    2015-01-01

    The intra-abdominal pressure (IAP) measurement is a key to diagnosing and managing critically ill medical and surgical patients. There are an increasing number of techniques that allow us to measure the IAP at the bedside. This paper reviews these techniques. IAP should be measured at end-expiration, with the patient in the supine position and ensuring that there is no abdominal muscle activity. The intravesicular IAP measurement is convenient and considered the gold standard. The level where the mid-axillary line crosses the iliac crest is the recommended zero reference for the transvesicular IAP measurement; moreover, marking this level on the patient increases reproducibility. Protocols for IAP measurement should be developed for each ICU based on the locally available tools and equipment. IAP measurement techniques are safe, reproducible and accurate and do not increase the risk of urinary tract infection. Continuous IAP measurement may offer benefits in specific situations in the future. In conclusion, the IAP measurement is a reliable and essential adjunct to the management of patients at risk of intra-abdominal hypertension.

  2. Intra-abdominal pressure correlates with extracellular water content.

    Directory of Open Access Journals (Sweden)

    Wojciech Dąbrowski

    Full Text Available Secondary increase in intra-abdominal pressure (IAP may result from extra-abdominal pathology, such as massive fluid resuscitation, capillary leak or sepsis. All these conditions increase the extravascular water content. The aim of this study was to analyze the relationship between IAP and body water volume.Adult patients treated for sepsis or septic shock with acute kidney injury (AKI and patients undergoing elective pharyngolaryngeal or orthopedic surgery were enrolled. IAP was measured in the urinary bladder. Total body water (TBW, extracellular water content (ECW and volume excess (VE were measured by whole body bioimpedance. Among critically ill patients, all parameters were analyzed over three consecutive days, and parameters were evaluated perioperatively in surgical patients.One hundred twenty patients were studied. Taken together, the correlations between IAP and VE, TBW, and ECW were measured at 408 time points. In all participants, IAP strongly correlated with ECW and VE. In critically ill patients, IAP correlated with ECW and VE. In surgical patients, IAP correlated with ECW and TBW. IAP strongly correlated with ECW and VE in the mixed population. IAP also correlated with VE in critically ill patients. ROC curve analysis showed that ECW and VE might be discriminative parameters of risk for increased IAP.IAP strongly correlates with ECW.

  3. High Blood Pressure

    Science.gov (United States)

    ... normal blood pressure 140/90 or higher is high blood pressure Between 120 and 139 for the top number, ... prehypertension. Prehypertension means you may end up with high blood pressure, unless you take steps to prevent it. High ...

  4. High Blood Pressure (Hypertension)

    Science.gov (United States)

    ... Print Page Text Size: A A A Listen High Blood Pressure (Hypertension) Nearly 1 in 3 American adults has ... weight. How Will I Know if I Have High Blood Pressure? High blood pressure is a silent problem — you ...

  5. Goal-Directed Fluid Therapy Guided by Cardiac Monitoring During High-Risk Abdominal Surgery in Adult Patients: Cost-Effectiveness Analysis of Esophageal Doppler and Arterial Pulse Pressure Waveform Analysis.

    Science.gov (United States)

    Legrand, Guillaume; Ruscio, Laura; Benhamou, Dan; Pelletier-Fleury, Nathalie

    2015-07-01

    Several minimally invasive techniques for cardiac output monitoring such as the esophageal Doppler (ED) and arterial pulse pressure waveform analysis (APPWA) have been shown to improve surgical outcomes compared with conventional clinical assessment (CCA). To evaluate the cost-effectiveness of these techniques in high-risk abdominal surgery from the perspective of the French public health insurance fund. An analytical decision model was constructed to compare the cost-effectiveness of ED, APPWA, and CCA. Effectiveness data were defined from meta-analyses of randomized clinical trials. The clinical end points were avoidance of hospital mortality and avoidance of major complications. Hospital costs were estimated by the cost of corresponding diagnosis-related groups. Both goal-directed therapy strategies evaluated were more effective and less costly than CCA. Perioperative mortality and the rate of major complications were reduced by the use of ED and APPWA. Cost reduction was mainly due to the decrease in the rate of major complications. APPWA was dominant compared with ED in 71.6% and 27.6% and dominated in 23.8% and 20.8% of the cases when the end point considered was "major complications avoided" and "death avoided," respectively. Regarding cost per death avoided, APPWA was more likely to be cost-effective than ED in a wide range of willingness to pay. Cardiac output monitoring during high-risk abdominal surgery is cost-effective and is associated with a reduced rate of hospital mortality and major complications, whatever the device used. The two devices evaluated had negligible costs compared with the observed reduction in hospital costs. Our comparative studies suggest a larger effect with APPWA that needs to be confirmed by further studies. Copyright © 2015 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  6. Hypertension (High Blood Pressure)

    Science.gov (United States)

    ... Loss Surgery? A Week of Healthy Breakfasts Shyness Hypertension (High Blood Pressure) KidsHealth > For Teens > Hypertension (High Blood Pressure) A ... rest temperature diet emotions posture medicines Why Is High Blood Pressure Bad? High blood pressure means a person's heart ...

  7. High pressure technology 1994

    Energy Technology Data Exchange (ETDEWEB)

    Kapp, J.A.; Picqueuer, L.M. (eds.)

    1994-01-01

    This volume is divided into four sessions: fracture mechanics applications to high pressure vessels; high pressure code issues; high pressure design, analysis, and safety concerns; and military and other high pressure applications. Separate abstracts were prepared for eleven papers of this conference.

  8. High blood pressure medications

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/007484.htm High blood pressure medicines To use the sharing features on this page, please enable JavaScript. Treating high blood pressure will help prevent problems such as heart disease, ...

  9. Treating High Blood Pressure

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    About High Blood Pressure Many people in the United States die from high blood pressure. This condition usually does not cause symptoms. Most ... until it is too late. A person has high blood pressure when the blood pushes against Visit your doctor ...

  10. High blood pressure - children

    Science.gov (United States)

    ... number is the diastolic pressure. This measures the pressure in the arteries when the heart is at rest. Blood pressure ... Medical Professional Call your child's provider if home monitoring shows that your child's blood pressure is still high. Prevention Your child's provider will ...

  11. [Intra-abdominal pressure as a surgery predictor in patients with acute abdominal pain].

    Science.gov (United States)

    Campos-Muñoz, Manuel Alejandro; Villarreal-Ríos, Enrique; Chimal-Torres, Mariano; Pozas-Medina, Josué Atila

    2016-01-01

    Introducción: la presión intraabdominal es el estado de equilibrio de la presión de la cavidad abdominal en reposo y puede presentar cambios durante la ventilación mecánica o espontánea. El objetivo fue determinar la presión intraabdominal como predictor de cirugía en el paciente con dolor abdominal agudo. Métodos: se llevó a cabo un estudio de casos y controles anidado en una cohorte de pacientes con dolor abdominal agudo en el servicio de urgencias de un hospital de segundo nivel, en el periodo comprendido entre abril y diciembre de 2013. Se incluyeron 37 pacientes, todos fueron intervenidos quirúrgicamente con previa toma de la presión intraabdominal. Se formaron los grupos con el resultado del estudio anatomopatológico: con evidencia de proceso inflamatorio abdominal agudo (n = 28) y sin evidencia de proceso inflamatorio abdominal agudo (n = 9). Resultados: en los casos el 100 % presentó presión intraabdominal alta con una p = 0.01, RM: 5 (IC 95 %: 2.578-9.699). En los casos la media de la presión intraabdominal fue de 11.46 y en los controles de 9.2 (p = 0.183). Conclusiones: el dolor abdominal que requiere cirugía para su resolución tiene relación directa con una presión intraabdominal > 5 mmHg.

  12. High-pressure apparatus

    NARCIS (Netherlands)

    Schepdael, van L.J.M.; Bartels, P.V.; Berg, van den R.W.

    1999-01-01

    The invention relates to a high-pressure device (1) having a cylindrical high-pressure vessel (3) and prestressing means in order to exert an axial pressure on the vessel. The vessel (3) can have been formed from a number of layers of composite material, such as glass, carbon or aramide fibers which

  13. The role of routine measurement of intra-abdominal pressure in preventing abdominal compartment syndrome

    Directory of Open Access Journals (Sweden)

    G Raghavendra Prasad

    2017-01-01

    Conclusion: Routine measure of IAP facilitates early recognition of IAH. This facilitates therapeutic measures to be initiated to reduce IAP. Early decision to decompress by laparotomy/laparostomy saves lives. Hence, routine IAP measurement should be a part of standard care in pediatric abdominal surgery.

  14. High Blood Pressure Facts

    Science.gov (United States)

    ... More black women than men have high blood pressure. 2 Race of Ethnic Group Men (%) Women (%) African Americans 43.0 45.7 Mexican Americans 27.8 28.9 Whites 33.9 31.3 All 34.1 32.7 Top of Page Why Blood Pressure Matters View this graphic snapshot of blood pressure ...

  15. Direct intra-abdominal pressure monitoring via piezoresistive pressure measurement: a technical note

    Directory of Open Access Journals (Sweden)

    Dembinski Rolf

    2009-04-01

    Full Text Available Abstract Background Piezoresistive pressure measurement technique (PRM has previously been applied for direct IAP measurement in a porcine model using two different devices. Aim of this clinical study was to assess both devices regarding complications, reliability and agreement with IVP in patients undergoing elective abdominal surgery. Methods A prospective cohort study was performed in 20 patients randomly scheduled to receive PRM either by a Coach®-probe or an Accurate++®-probe (both MIPM, Mammendorf, Germany. Probes were placed on the greater omentum and passed through the abdominal wall paralleling routine drainages. PRM was compared with IVP measurement by t-testing and by calculating mean difference as well as limits of agreement (LA. Results There were no probe related complications. Due to technical limitations, data could be collected in 3/10 patients with Coach® and in 7/10 patients with Accurate++®. Analysis was carried out only for Accurate++®. Mean values did not differ to mean IVP values. Mean difference to IVP was 0.1 ± 2.8 mmHg (LA: -5.5 to 5.6 mmHg. Conclusion Direct IAP measurement was clinically uneventful. Although results of Accurate++® were comparable to IVP, the device might be too fragile for IAP measurements in the clinical setting. Local ethical committee trial registration: EK2024

  16. Direct intra-abdominal pressure monitoring via piezoresistive pressure measurement: a technical note

    Science.gov (United States)

    Otto, Jens; Kaemmer, Daniel; Binnebösel, Marcel; Jansen, Marc; Dembinski, Rolf; Schumpelick, Volker; Schachtrupp, Alexander

    2009-01-01

    Background Piezoresistive pressure measurement technique (PRM) has previously been applied for direct IAP measurement in a porcine model using two different devices. Aim of this clinical study was to assess both devices regarding complications, reliability and agreement with IVP in patients undergoing elective abdominal surgery. Methods A prospective cohort study was performed in 20 patients randomly scheduled to receive PRM either by a Coach®-probe or an Accurate++®-probe (both MIPM, Mammendorf, Germany). Probes were placed on the greater omentum and passed through the abdominal wall paralleling routine drainages. PRM was compared with IVP measurement by t-testing and by calculating mean difference as well as limits of agreement (LA). Results There were no probe related complications. Due to technical limitations, data could be collected in 3/10 patients with Coach® and in 7/10 patients with Accurate++®. Analysis was carried out only for Accurate++®. Mean values did not differ to mean IVP values. Mean difference to IVP was 0.1 ± 2.8 mmHg (LA: -5.5 to 5.6 mmHg). Conclusion Direct IAP measurement was clinically uneventful. Although results of Accurate++® were comparable to IVP, the device might be too fragile for IAP measurements in the clinical setting. Local ethical committee trial registration: EK2024 PMID:19383161

  17. Deleterious Effects of Increased Intra-Abdominal Pressure on Kidney Function

    Directory of Open Access Journals (Sweden)

    Zaher Armaly

    2014-01-01

    Full Text Available Elevated intra-abdominal pressure (IAP occurs in many clinical settings, including sepsis, severe acute pancreatitis, acute decompensated heart failure, hepatorenal syndrome, resuscitation with large volume, mechanical ventilation with high intrathoracic pressure, major burns, and acidosis. Although increased IAP affects several vital organs, the kidney is very susceptible to the adverse effects of elevated IAP. Kidney dysfunction is among the earliest physiological consequences of increased IAP. In the last two decades, laparoscopic surgery is rapidly replacing the open approach in many areas of surgery. Although it is superior at many aspects, laparoscopic surgery involves elevation of IAP, due to abdominal insufflation with carbonic dioxide (pneumoperitoneum. The latter has been shown to cause several deleterious effects where the most recognized one is impairment of kidney function as expressed by oliguria and reduced glomerular filtration rate (GFR and renal blood flow (RBF. Despite much research in this field, the systemic physiologic consequences of elevated IAP of various etiologies and the mechanisms underlying its adverse effects on kidney excretory function and renal hemodynamics are not fully understood. The current review summarizes the reported adverse renal effects of increased IAP in edematous clinical settings and during laparoscopic surgery. In addition, it provides new insights into potential mechanisms underlying this phenomenon and therapeutic approaches to encounter renal complications of elevated IAP.

  18. High blood pressure - infants

    Science.gov (United States)

    ... Certain tumors Inherited conditions (problems that run in families) Thyroid problems Blood pressure rises as the baby grows. The average blood ... vomiting constantly Prevention Some causes of high blood pressure run in families. Talk to your provider before you get pregnant ...

  19. Preventing High Blood Pressure

    Science.gov (United States)

    ... Web Sites Division for Heart Disease and Stroke Prevention Stroke Heart Disease Cholesterol Salt Million Hearts® WISEWOMAN Preventing High Blood Pressure: Healthy Living Habits Recommend on Facebook Tweet Share Compartir By living a healthy lifestyle, you can help keep your blood pressure in ...

  20. SU-E-J-190: Development of Abdominal Compression & Respiratory Guiding System Using Gas Pressure Sensor

    Energy Technology Data Exchange (ETDEWEB)

    Kim, T; Kim, D; Kang, S; Cho, M; Kim, K; Shin, D; Suh, T [The Catholic University of Korea College of Medicine, Seoul (Korea, Republic of); Kim, S [Virginia Commonwealth University, Richmond, VA (United States)

    2015-06-15

    Purpose: Abdominal compression is known to be effective but, often makes external-marker-based monitoring of breathing motion not feasible. In this study, we developed and evaluated a system that enables both abdominal compression and monitoring of residual abdominal motion simultaneously. The system can also provide visual-biofeedback capability. Methods: The system developed consists of a compression belt, an abdominal motion monitoring sensor (gas pressure sensor) and a visual biofeedback device. The compression belt was designed to be able to compress the frontal side of the abdomen. The pressure level of the belt is controlled by air volume and monitored in real time using the gas pressure sensor. The system displays not only the real-time monitoring curve but also a guiding respiration model (e.g., a breath hold or shallow breathing curve) simultaneously on the head mounted display to help patients keep their breathing pattern as consistent as possible. Three healthy volunteers were enrolled in this pilot study and respiratory signals (pressure variations) were obtained both with and without effective abdominal compression to investigate the feasibility of the developed system. Two guidance patterns, breath hold and shallow breathing, were tested. Results: All volunteers showed smaller abdominal motion with compression (about 40% amplitude reduction compared to without compression). However, the system was able to monitor residual abdominal motion for all volunteers. Even under abdominal compression, in addition, it was possible to make the subjects successfully follow the guide patterns using the visual biofeedback system. Conclusion: The developed abdominal compression & respiratory guiding system was feasible for residual abdominal motion management. It is considered that the system can be used for a respiratory motion involved radiation therapy while maintaining the merit of abdominal compression. This work was supported by the Radiation Technology R

  1. High Blood Pressure (Hypertension)

    Science.gov (United States)

    ... already been diagnosed with high blood pressure. Try yoga and meditation. Yoga and meditation not only can strengthen your body ... Accessed Sept. 21, 2015. Hu B, et al. Effects of psychological stress on hypertension in middle-aged ...

  2. Intra-abdominal pressure and possible ways of its drug correction after emergency laparotomy

    Directory of Open Access Journals (Sweden)

    Людмила Василівна Новицька-Усенко

    2015-11-01

    Full Text Available Introduction. Postoperative disorders of gastrointestinal tract (GIT motility are often after abdominal operations. Postoperative enteroparesis is usually accompanied by the raise of intra-abdominal pressure (IAP.Materials and methods. After approval of research by bioethics committee and informed consent 52 patients were prospectively divided in 2 groups depending on the type of postoperative intensive care. Patients underwent operations on abdominal cavity by laparotomy incision on the subject of peritonitis. Patient of the 1 (control group (n=27 after operation received stimulation of GIT with metoclopramide and simethicone.  In the 2 group (n=25 patients received metoclopramide and simethicone. Patients were comparable on age, sex, concomitant pathology, ASA class (IIE-IIIE and the type of operative intervention (laparotomy on the subject of peritonitis. IAP level was studied before operation and at 1,2,3 days after it. IAP was measured by indirect method trough the urinary bladder. The values recommended by the World society of abdominal compartment syndrome were considered as the normal IAP level.  Perfuse pressure (PP in abdominal cavity was calculated by formula: PP=MAP-ICP where MAP – mean arterial pressure. There were also studied indices of the central and peripheral hemodynamics, inflammation markers (leukocytes, fibrinogen level, IL-1α, TNFα, IL-10, leukocytic index of intoxication was calculated. The final point of research was 28 day after operation when we evaluated mortality and life quality on Rancho Los Amigos scale.Results and discussion. We registered the raise of IAP in 63.1% of patients. The value of intra-abdominal pressure exceeded an upper limit of the normal one by 58,5% (р <0,001. Among patients with high IAP 83% had intra-abdominal hypertension (IAH of 1 degree, 17% - of 2 degree.  The development of 3 and 4degree IAH were not observed before operation. PP remained within the normal.Correlative analysis

  3. Prevention of High Blood Pressure

    Science.gov (United States)

    ... page from the NHLBI on Twitter. Prevention of High Blood Pressure Healthy lifestyle habits, proper use of medicines, and ... prevent high blood pressure or its complications. Preventing High Blood Pressure Onset Healthy lifestyle habits can help prevent high ...

  4. High Blood Pressure Fact Sheet

    Science.gov (United States)

    ... High Blood Pressure Salt Cholesterol Million Hearts® WISEWOMAN High Blood Pressure Fact Sheet Language: English Español (Spanish) Recommend on ... time. High blood pressure is also called hypertension. High Blood Pressure in the United States Having high blood pressure ...

  5. "EFFECTIVENESS OF ABDOMINAL WALL ELEVATOR IN REDUCING INTRA-ABDOMINAL PRESSURE AND CO2 VOLUME DURING LAPAROSCOPIC CHOLECYSTECTOMY"

    Directory of Open Access Journals (Sweden)

    A. Yaghoobi Notash

    2004-06-01

    Full Text Available Since CO2 pneumoperitoneum is the dominant method of laparoscopic exposure due to facility and good view, its physiologic effects are most relevant to the surgeons. CO2 pneumoperitoneum may affects hemodynamics by increased intra-abdominal pressure (IAP and the physiologic effects of absorbed CO2. The adverse effects of both mechanisms relate directly to the duration of the pneumoperitoneum and the elevation of IAP. Gasless laparoscopy involves obtaining exposure for laparoscopy by placing an internal retracting device through a small incision and lifting the anterior abdominal wall. We designed and made a mechanical wall elevator and used it in 24 patients, compared with a control group (52 cases using a conventional laparoscopic cholecystectomy. A prospective trial was undertaken in Sina Hospital, Tehran University of Medical Sciences from 1998 to 2000. The patients were assigned randomly to two groups. There was a significant decrease in IAP and CO2 consumption in the group using mechanical wall elevator as compared to conventional laparoscopic cholecystectomy, (mean IAP of 3.5 mmHg compared to 11.4 mmHg in the control group, mean CO2 volume 17 liters compared to 73 liters in the control group. We recommend this semigasless method in laparoscopy due to safety in performance and significant reduction in IAP through the surgery. This method provides a satisfactory view and easy performance without any increase in time or complications. The hospital stay and costs did not increase.

  6. Increased Intra-Abdominal Pressure Causes Bacterial Translocation in Rabbits

    Directory of Open Access Journals (Sweden)

    Gokhan Yagci

    2005-04-01

    Conclusion: We propose that an intravesical pressure (IVP of 15 mmHg is the critical point for BT in patients with increased IAP. In this experimental study, BT occurred when IVP reached 20 mmHg. We suggest that IVP monitoring is desirable in the management of patients with ACS, and that decompressive laparotomy should be performed in patients with IVP > 20 mmHg.

  7. Diagnosis of High Blood Pressure

    Medline Plus

    Full Text Available ... the NHLBI on Twitter. Diagnosis of High Blood Pressure For most patients, health care providers diagnose high ... 140/90 mmHg or above. Confirming High Blood Pressure A blood pressure test is easy and painless ...

  8. High Pressure Biomass Gasification

    Energy Technology Data Exchange (ETDEWEB)

    Agrawal, Pradeep K [Georgia Tech Research Corporation, Atlanta, GA (United States)

    2016-07-29

    According to the Billion Ton Report, the U.S. has a large supply of biomass available that can supplement fossil fuels for producing chemicals and transportation fuels. Agricultural waste, forest residue, and energy crops offer potential benefits: renewable feedstock, zero to low CO2 emissions depending on the specific source, and domestic supply availability. Biomass can be converted into chemicals and fuels using one of several approaches: (i) biological platform converts corn into ethanol by using depolymerization of cellulose to form sugars followed by fermentation, (ii) low-temperature pyrolysis to obtain bio-oils which must be treated to reduce oxygen content via HDO hydrodeoxygenation), and (iii) high temperature pyrolysis to produce syngas (CO + H2). This last approach consists of producing syngas using the thermal platform which can be used to produce a variety of chemicals and fuels. The goal of this project was to develop an improved understanding of the gasification of biomass at high pressure conditions and how various gasification parameters might affect the gasification behavior. Since most downstream applications of synags conversion (e.g., alcohol synthesis, Fischer-Tropsch synthesis etc) involve utilizing high pressure catalytic processes, there is an interest in carrying out the biomass gasification at high pressure which can potentially reduce the gasifier size and subsequent downstream cleaning processes. It is traditionally accepted that high pressure should increase the gasification rates (kinetic effect). There is also precedence from coal gasification literature from the 1970s that high pressure gasification would be a beneficial route to consider. Traditional approach of using thermogravimetric analyzer (TGA) or high-pressure themogravimetric analyzer (PTGA) worked well in understanding the gasification kinetics of coal gasification which was useful in designing high pressure coal gasification processes. However

  9. Effect of hemodialysis on intra-abdominal pressure Efeito da hemodiálise sobre a pressão intra-abdominal

    Directory of Open Access Journals (Sweden)

    Roberta Fernandes Bonfim

    2007-01-01

    Full Text Available OBJECTIVE: To study the effect of hemodialysis on intra-abdominal pressure. METHODS: Five patients admitted between July and November of 2003 were evaluated in the intensive care unit. Intra-abdominal pressure was measured before and after hemodialysis, maintaining the ventilatory parameters except for PEEP (positive-end expiratory pressure. RESULTS: Intra-abdominal pressure was significantly reduced by hemodialysis in all the 5 patients. CONCLUSION: Hemodialysis significantly reduced intra-abdominal pressure in the 5 patients, an effect which could have influence over other organic systems. This reduction is related to the weight variation before and after hemodialysis, as well as to the loss of volume caused by this procedure.OBJETIVO: Pesquisar o efeito da hemodiálise sobre a pressão intra-abdominal. MÉTODOS: Foram avaliados cinco pacientes internados entre julho e novembro de 2003, na Unidade de Terapia Intensiva do Serviço de Nefrologia do Hospital das Clínicas de São Paulo. Mensurou-se a pressão intra-abdominal antes e após a hemodiálise, mantendo os parâmetros ventilatórios exceto a PEEP (positive end expiratory pressure. RESULTADOS: Constatou-se que a hemodiálise foi capaz de reduzir significativamente a PIA em cinco pacientes na Unidade de Terapia Intensiva CONCLUSÃO: A hemodiálise reduziu a pressão intra-abdominal numa amostra de cinco pacientes, de maneira significativa, o que poderia influenciar os demais sistemas orgânicos. Essa redução está relacionada com a variação de peso pré e pós-hemodiálise, e com a perda de volume promovida pelo procedimento.

  10. Diagnosis of High Blood Pressure

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    Full Text Available ... Blood Pressure » Diagnosis of High Blood Pressure Explore High Blood Pressure What Is... Other Names Causes Who Is at Risk Signs & Symptoms Diagnosis Treatments Prevention Living With Clinical ...

  11. Living with High Blood Pressure

    Science.gov (United States)

    ... page from the NHLBI on Twitter. Living With High Blood Pressure If you have high blood pressure, the best thing to do is to talk ... help you track your blood pressure. Pregnancy Planning High blood pressure can cause problems for mother and baby. High ...

  12. Diagnosis of High Blood Pressure

    Medline Plus

    Full Text Available ... High Blood Pressure Explore High Blood Pressure What Is... Other Names Causes Who Is at Risk Signs & Symptoms Diagnosis Treatments Prevention Living ... Confirming High Blood Pressure A blood pressure test is easy and painless and can be done in ...

  13. Abdominal Twin Pressure Sensors for the assessment of abdominal injuries in Q dummies: in-dummy evaluation and performance in accident reconstructions.

    Science.gov (United States)

    Beillas, Philippe; Alonzo, François; Chevalier, Marie-Christine; Lesire, Philippe; Leopold, Franck; Trosseille, Xavier; Johannsen, Heiko

    2012-10-01

    The Abdominal Pressure Twin Sensors (APTS) for Q3 and Q6 dummies are composed of soft polyurethane bladders filled with fluid and equipped with pressure sensors. Implanted within the abdominal insert of child dummies, they can be used to detect abdominal loading due to the belt during frontal collisions. In the present study - which is part of the EC funded CASPER project - two versions of APTS (V1 and V2) were evaluated in abdominal belt compression tests, torso flexion test (V1 only) and two series of sled tests with degraded restraint conditions. The results suggest that the two versions have similar responses, and that the pressure sensitivity to torso flexion is limited. The APTS ability to detect abdominal loading in sled tests was also confirmed, with peak pressures typically below 1 bar when the belt loaded only the pelvis and the thorax (appropriate restraint) and values above that level when the abdomen was loaded directly (inappropriate restraint). Then, accident reconstructions performed as part of CASPER and previous EC funded projects were reanalyzed. Selected data from 19 dummies (12 Q6 and 7 Q3) were used to plot injury risk curves. Maximum pressure, maximum pressure rate and their product were all found to be injury predictors. Maximum pressure levels for a 50% risk of AIS3+ were consistent with the levels separating appropriate and inappropriate restraint in the sled tests (e.g. 50% risk of AIS3+ at 1.09 bar for pressure filtered CFC180). Further work is needed to refine the scaling techniques between ages and confirm the risk curves.

  14. Diagnosis of High Blood Pressure

    Medline Plus

    Full Text Available ... providers diagnose high blood pressure when blood pressure readings are consistently 140/90 mmHg or above. Confirming ... minutes before the test. To track blood pressure readings over a period of time, the health care ...

  15. Pressure Dome for High-Pressure Electrolyzer

    Science.gov (United States)

    Norman, Timothy; Schmitt, Edwin

    2012-01-01

    A high-strength, low-weight pressure vessel dome was designed specifically to house a high-pressure [2,000 psi (approx. = 13.8 MPa)] electrolyzer. In operation, the dome is filled with an inert gas pressurized to roughly 100 psi (approx. = 690 kPa) above the high, balanced pressure product oxygen and hydrogen gas streams. The inert gas acts to reduce the clamping load on electrolyzer stack tie bolts since the dome pressure acting axially inward helps offset the outward axial forces from the stack gas pressure. Likewise, radial and circumferential stresses on electrolyzer frames are minimized. Because the dome is operated at a higher pressure than the electrolyzer product gas, any external electrolyzer leak prevents oxygen or hydrogen from leaking into the dome. Instead the affected stack gas stream pressure rises detectably, thereby enabling a system shutdown. All electrical and fluid connections to the stack are made inside the pressure dome and require special plumbing and electrical dome interfaces for this to be accomplished. Further benefits of the dome are that it can act as a containment shield in the unlikely event of a catastrophic failure. Studies indicate that, for a given active area (and hence, cell ID), frame outside diameter must become ever larger to support stresses at higher operating pressures. This can lead to a large footprint and increased costs associated with thicker and/or larger diameter end-plates, tie-rods, and the frames themselves. One solution is to employ rings that fit snugly around the frame. This complicates stack assembly and is sometimes difficult to achieve in practice, as its success is strongly dependent on frame and ring tolerances, gas pressure, and operating temperature. A pressure dome permits an otherwise low-pressure stack to operate at higher pressures without growing the electrolyzer hardware. The pressure dome consists of two machined segments. An O-ring is placed in an O-ring groove in the flange of the bottom

  16. Chromium at High Pressure

    Science.gov (United States)

    Jaramillo, Rafael

    2012-02-01

    Chromium has long served as the archetype of spin density wave magnetism. Recently, Jaramillo and collaborators have shown that Cr also serves as an archetype of magnetic quantum criticality. Using a combination of x-ray diffraction and electrical transport measurements at high pressures and cryogenic temperatures in a diamond anvil cell, they have demonstrated that the N'eel transition (TN) can be continuously suppressed to zero, with no sign of a concurrent structural transition. The order parameter undergoes a broad regime of exponential suppression, consistent with the weak coupling paradigm, before deviating from a BCS-like ground state within a narrow but accessible quantum critical regime. The quantum criticality is characterized by mean field scaling of TN and non mean field scaling of the transport coefficients, which points to a fluctuation-induced reconstruction of the critical Fermi surface. A comparison between pressure and chemical doping as means to suppress TN sheds light on different routes to the quantum critical point and the relevance of Fermi surface nesting and disorder at this quantum phase transition. The work by Jaramillo et al. is broadly relevant to the study of magnetic quantum criticality in a physically pure and theoretically tractable system that balances elements of weak and strong coupling. [4pt] [1] R. Jaramillo, Y. Feng, J. Wang & T. F. Rosenbaum. Signatures of quantum criticality in pure Cr at high pressure. Proc. Natl. Acad. Sci. USA 107, 13631 (2010). [0pt] [2] R. Jaramillo, Y. Feng, J. C. Lang, Z. Islam, G. Srajer, P. B. Littlewood, D. B. McWhan & T. F. Rosenbaum. Breakdown of the Bardeen-Cooper-Schrieffer ground state at a quantum phase transition. Nature 459, 405 (2009).

  17. High Blood Pressure

    Science.gov (United States)

    ... mmHg People read "118 over 76" millimeters of mercury. Normal Blood Pressure Normal blood pressure for adults ... health. Share your story with other women on Facebook . The Heart Truth campaign offers a variety of ...

  18. High Blood Pressure Increasing Worldwide

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_162977.html High Blood Pressure Increasing Worldwide And health risks may appear even ... of people around the world with elevated or high blood pressure increases, so do the number of deaths linked ...

  19. Medications for High Blood Pressure

    Science.gov (United States)

    ... Consumers Home For Consumers Consumer Updates Medications for High Blood Pressure Share Tweet Linkedin Pin it More sharing options ... age and you cannot tell if you have high blood pressure by the way you feel, so have your ...

  20. What Causes High Blood Pressure?

    Science.gov (United States)

    ... page from the NHLBI on Twitter. Causes of High Blood Pressure Changes, either from genes or the environment, in ... and blood vessel structure and function. Biology and High Blood Pressure Researchers continue to study how various changes in ...

  1. Diagnosis of High Blood Pressure

    Medline Plus

    Full Text Available ... page from the NHLBI on Twitter. Diagnosis of High Blood Pressure For most patients, health care providers diagnose high ... are consistently 140/90 mmHg or above. Confirming High Blood Pressure A blood pressure test is easy and painless ...

  2. Diagnosis of High Blood Pressure

    Medline Plus

    Full Text Available ... page from the NHLBI on Twitter. Diagnosis of High Blood Pressure For most patients, health care providers diagnose high ... are consistently 140/90 mmHg or above. Confirming High Blood Pressure A blood pressure test is easy and painless ...

  3. Controlling your high blood pressure

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000101.htm Controlling your high blood pressure To use the sharing features on this page, ... JavaScript. Hypertension is another term used to describe high blood pressure. High blood pressure can lead to: Stroke Heart ...

  4. Diagnosis of High Blood Pressure

    Science.gov (United States)

    ... page from the NHLBI on Twitter. Diagnosis of High Blood Pressure For most patients, health care providers diagnose high ... are consistently 140/90 mmHg or above. Confirming High Blood Pressure A blood pressure test is easy and painless ...

  5. Effects of Altered Intra-abdominal Pressure on the Upper Airway Collapsibility in a Porcine Model

    Institute of Scientific and Technical Information of China (English)

    Shu-Lin Ren; Yan-Ru Li; Ji-Xiang Wu; Jing-Ying Ye; Rachel Jen

    2015-01-01

    Background: Obstructive sleep apnea is strongly associated with obesity, particularly abdominal obesity common in centrally obese males.Previous studies have demonstrated that intra-abdominal pressure (IAP) is increased in morbid obesity, and tracheal traction forces may influence pharyngeal airway collapsibility.This study aimed to investigate that whether IAP plays a role in the mechanism of upper airway (UA) collapsibility via IAP-related caudal tracheal traction.Methods: An abdominal wall lifting (AWL) system and graded CO2 pneumoperitoneum pressure was applied to four supine, anesthetized Guizhou miniature pigs and its effects on tracheal displacement (TD) and airflow dynamics of UA were studied.Individual run data in 3 min obtained before and after AWL and obtained before and after graded pneumoperitoneum pressure were analyzed.Differences between baseline and AWL/graded pneumoperitoneum pressure data of each pig were examined using a Student's t-test or analysis of variance.Results: Application of AWL resulted in decreased IAP and significant caudal TD.The average displacement amplitude was 0.44 mm (P < 0.001).There were three subjects showed increased tidal volume (TV) (P < 0.0l) and peak inspiratory airflow (P < 0.01);however, the change of flow limitation inspiratory UA resistance (Rua) was not significant.Experimental increased IAP by pneumoperitoneum resulted in significant cranial TD.The average displacement amplitude was 1.07 mm (P < 0.001) when IAP was 25 cmH20 compared to baseline.There were three subjects showed reduced Rua while the TV increased (P < 0.01).There was one subject had decreased TV and elevated Rua (P < 0.001).Conclusions: Decreased IAP significantly increased caudal TD, and elevated IAP significantly increased cranial TD.However, the mechanism of UA collapsibility appears primarily mediated by changes in lung volume rather than tracheal traction effect.TV plays an independent role in the mechanism of UA collapsibility.

  6. [High Pressure Gas Tanks

    Science.gov (United States)

    Quintana, Rolando

    2002-01-01

    Four high-pressure gas tanks, the basis of this study, were especially made by a private contractor and tested before being delivered to NASA Kennedy Space Center. In order to insure 100% reliability of each individual tank the staff at KSC decided to again submit the four tanks under more rigorous tests. These tests were conducted during a period from April 10 through May 8 at KSC. This application further validates the predictive safety model for accident prevention and system failure in the testing of four high-pressure gas tanks at Kennedy Space Center, called Continuous Hazard Tracking and Failure Prediction Methodology (CHTFPM). It is apparent from the variety of barriers available for a hazard control that some barriers will be more successful than others in providing protection. In order to complete the Barrier Analysis of the system, a Task Analysis and a Biomechanical Study were performed to establish the relationship between the degree of biomechanical non-conformities and the anomalies found within the system on particular joints of the body. This relationship was possible to obtain by conducting a Regression Analysis to the previously generated data. From the information derived the body segment with the lowest percentage of non-conformities was the neck flexion with 46.7%. Intense analysis of the system was conducted including Preliminary Hazard Analysis (PHA), Failure Mode and Effect Analysis (FMEA), and Barrier Analysis. These analyses resulted in the identification of occurrences of conditions, which may be becoming hazardous in the given system. These conditions, known as dendritics, may become hazards and could result in an accident, system malfunction, or unacceptable risk conditions. A total of 56 possible dendritics were identified. Work sampling was performed to observe the occurrence each dendritic. The out of control points generated from a Weighted c control chart along with a Pareto analysis indicate that the dendritics "Personnel not

  7. Pain pressure threshold algometry of the abdominal wall in healthy women

    Directory of Open Access Journals (Sweden)

    M.L.L.S. Montenegro

    2012-07-01

    Full Text Available The objective of this study was to determine the inter- and intra-examiner reliability of pain pressure threshold algometry at various points of the abdominal wall of healthy women. Twenty-one healthy women in menacme with a mean age of 28 ± 5.4 years (range: 19-39 years were included. All volunteers had regular menstrual cycles (27-33 days and were right-handed and, to the best of our knowledge, none were taking medications at the time of testing. Women with a diagnosis of depression, anxiety or other mood disturbances were excluded. Women with previous abdominal surgery, any pain condition or any evidence of inflammation, hypertension, smoking, alcoholism, or inflammatory disease were also excluded. Pain perception thresholds were assessed with a pressure algometer with digital traction and compression and a measuring capacity for 5 kg. All points were localized by palpation and marked with a felt-tipped pen and each individual was evaluated over a period of 2 days in two consecutive sessions, each session consisting of a set of 14 point measurements repeated twice by two examiners in random sequence. There was no statistically significant difference in the mean pain threshold obtained by the two examiners on 2 diferent days (examiner A: P = 1.00; examiner B: P = 0.75; Wilcoxon matched pairs test. There was excellent/good agreement between examiners for all days and all points. Our results have established baseline values to which future researchers will be able to refer. They show that pressure algometry is a reliable measure for pain perception in the abdominal wall of healthy women.

  8. Pain pressure threshold algometry of the abdominal wall in healthy women

    Directory of Open Access Journals (Sweden)

    M.L.L.S. Montenegro

    2012-07-01

    Full Text Available The objective of this study was to determine the inter- and intra-examiner reliability of pain pressure threshold algometry at various points of the abdominal wall of healthy women. Twenty-one healthy women in menacme with a mean age of 28 ± 5.4 years (range: 19-39 years were included. All volunteers had regular menstrual cycles (27-33 days and were right-handed and, to the best of our knowledge, none were taking medications at the time of testing. Women with a diagnosis of depression, anxiety or other mood disturbances were excluded. Women with previous abdominal surgery, any pain condition or any evidence of inflammation, hypertension, smoking, alcoholism, or inflammatory disease were also excluded. Pain perception thresholds were assessed with a pressure algometer with digital traction and compression and a measuring capacity for 5 kg. All points were localized by palpation and marked with a felt-tipped pen and each individual was evaluated over a period of 2 days in two consecutive sessions, each session consisting of a set of 14 point measurements repeated twice by two examiners in random sequence. There was no statistically significant difference in the mean pain threshold obtained by the two examiners on 2 diferent days (examiner A: P = 1.00; examiner B: P = 0.75; Wilcoxon matched pairs test. There was excellent/good agreement between examiners for all days and all points. Our results have established baseline values to which future researchers will be able to refer. They show that pressure algometry is a reliable measure for pain perception in the abdominal wall of healthy women.

  9. Effects of intra-abdominal pressure on adrenal gland function and morphology in rats.

    Science.gov (United States)

    Akkapulu, Nezih; Tirnaksiz, Mehmet Bulent; Kulac, Ibrahim; Tezel, Gaye Guler; Hayran, Mutlu; Dogrul, Ahmet Bulent; Cetinkaya, Erdinc; Yorganci, Kaya

    2015-01-01

    Intra-abdominal hypertension and abdominal compartment syndrome (IAH/ACS) are life-threatening conditions and caused by several clinical status. Although there is insufficient data regarding its effects on adrenal glands. This study aimed to identify whether elevated intra-abdominal pressure (IAP) caused any alteration on the morphology and function of adrenal glands in a rat model. Twenty four Sprague-Dawley male rats were included in the study. Animals were allocated into 4 groups. IAP was elevated to 15 mmHg for one hour and four hours in group 2 and 4. Group 1 and 3 were sham groups. Blood samples were taken for the assessment of plasma adrenaline, noradrenaline, and corticosterone levels and adrenalectomies were performed to evaluate apoptosis. Blood adrenaline, noradrenaline and corticosterone levels were significantly higher in the study groups compared with the sham groups. However, there were no significant changes in apoptotic index scores in the study groups as compared to sham groups. These results support that increased IAH leads to discharge of catecholamine and corticosterone from the adrenal glands. Failure to demonstrate similar changes in apoptotic index score may be concluded as apoptosis is not a leading pathway for impairment of adrenal glands during IAH period.

  10. Analyzing intra-abdominal pressures and outcomes in patients undergoing emergency laparotomy

    Directory of Open Access Journals (Sweden)

    Khan Shehtaj

    2010-01-01

    Full Text Available Background : Studies have documented the impact of intra-abdominal hypertension (IAH on virtually every organ. However, it still remains strangely underdiagnosed. The aims of the study were to assess, in patients undergoing emergency laparotomy, whether intra-abdominal pressure (IAP is an independent predictor of morbidity and mortality, to evaluate the effects of IAH, and to identify hidden cases of abdominal compartment syndrome (ACS. Materials and Methods : The study comprised 197 patients undergoing emergency laparotomy. IAP was measured preoperatively and then postoperatively at 0, 6, and 24 hours. Duration of hospital stay, occurrence of burst abdomen, and mortality were noted as outcomes. Results : At admission, incidence of IAH was 80%. No significant association was found between IAP and occurrence of burst abdomen (P > 0.1. IAP was found to be a significant predictor of mortality in patients undergoing laparotomy (P < 0.001. Elevated IAP was found to affect all the organ systems adversely. The incidence of post-op ACS was 3.05% in the general population and 13.16% in trauma patients. The mortality rate for this subgroup was 100%. Conclusions : IAP is a significant predictor of mortality in patients undergoing laparotomy. IAH has detrimental effects on various organ systems. A more frequent monitoring with prompt decompression may be helpful in decreasing the mortality rate. Further studies are required to establish a screening protocol in patients undergoing laparotomy to detect and manage cases of IAH and ACS.

  11. High-pressure neutron diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Hongwu [Los Alamos National Laboratory

    2011-01-10

    This lecture will cover progress and prospect of applications of high-pressure neutron diffraction techniques to Earth and materials sciences. I will first introduce general high-pressure research topics and available in-situ high-pressure techniques. Then I'll talk about high-pressure neutron diffraction techniques using two types of pressure cells: fluid-driven and anvil-type cells. Lastly, I will give several case studies using these techniques, particularly, those on hydrogen-bearing materials and magnetic transitions.

  12. Diagnosis of High Blood Pressure

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    Full Text Available ... and Obesity Smoking and Your Heart Stroke Send a link to NHLBI to someone by E-MAIL | ... 90 mmHg or above. Confirming High Blood Pressure A blood pressure test is easy and painless and ...

  13. Diagnosis of High Blood Pressure

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    Full Text Available ... of Intramural Research Research Resources Research Meeting Summaries Technology Transfer Clinical Trials What Are Clinical Trials? Children & ... blood pressure is due to other conditions or medicines or if you have primary high blood pressure. ...

  14. Diagnosis of High Blood Pressure

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    Full Text Available ... to keep a written log of all your results. Whenever you have an appointment with the health ... appointments to diagnose high blood pressure. Using the results of your blood pressure test, your health care ...

  15. High Blood Pressure in Pregnancy

    Science.gov (United States)

    ... of the baby. Controlling your blood pressure during pregnancy and getting regular prenatal care are important for ... your baby. Treatments for high blood pressure in pregnancy may include close monitoring of the baby, lifestyle ...

  16. Diagnosis of High Blood Pressure

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    Full Text Available ... ask for your readings. Blood Pressure Severity and Type Your health care provider usually takes 2–3 ... any other location. Health care providers diagnose this type of high blood pressure by reviewing readings in ...

  17. Diagnosis of High Blood Pressure

    Medline Plus

    Full Text Available ... ask for your readings. Blood Pressure Severity and Type Your health care provider usually takes 2–3 ... any other location. Health care providers diagnose this type of high blood pressure by reviewing readings in ...

  18. Diagnosis of High Blood Pressure

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    Full Text Available ... above. Confirming High Blood Pressure A blood pressure test is easy and painless and can be done ... provider’s office or clinic. To prepare for the test: Don’t drink coffee or smoke cigarettes for ...

  19. Diagnosis of High Blood Pressure

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    Full Text Available ... readings. Blood Pressure Severity and Type Your health care provider usually takes 2–3 readings at several medical appointments to diagnose high blood pressure. Using the ...

  20. Diagnosis of High Blood Pressure

    Medline Plus

    Full Text Available ... and Obesity Smoking and Your Heart Stroke Send a link to NHLBI to someone by E-MAIL | ... 90 mmHg or above. Confirming High Blood Pressure A blood pressure test is easy and painless and ...

  1. Diagnosis of High Blood Pressure

    Medline Plus

    Full Text Available ... above. Confirming High Blood Pressure A blood pressure test is easy and painless and can be done ... provider’s office or clinic. To prepare for the test: Don’t drink coffee or smoke cigarettes for ...

  2. Low Transmission of Airway Pressures to the Abdomen in Mechanically Ventilated Patients With or Without Acute Respiratory Failure and Intra-Abdominal Hypertension.

    Science.gov (United States)

    Heijnen, Bram G A D H; Spoelstra-de Man, Angelique M E; Groeneveld, A B Johan

    2017-03-01

    Intra-abdominal pressure, measured at end expiration, may depend on ventilator settings and transmission of intrathoracic pressure. We determined the transmission of positive intrathoracic pressure during mechanical ventilation at inspiration and expiration into the abdominal compartment. We included 9 patients after uncomplicated cardiac surgery and 9 with acute respiratory failure. Intravesical pressures were measured thrice (reproducibility of 1.8%) and averaged, at the end of each inspiratory and expiratory hold maneuvers of 5 seconds. Transmission, the change in intra-abdominal over intrathoracic pressures from end inspiration to end expiration, was about 8%. End-expiratory intra-abdominal pressure was lower than "total" intra-abdominal pressure over the entire respiratory cycle by 0.34 cm H2O. It was 0.73 cm H2O higher than "true" intra-abdominal pressure over the entire respiratory cycle, taking transmission into account. The percentage error was 3% for total and 10% for true pressure. Results did not differ among patients with or without acute respiratory failure and decreased respiratory compliance or between those with (≥12 mm Hg, n = 5) or without intra-abdominal hypertension. Transmitted airway pressure only slightly affects intra-abdominal pressure in mechanically ventilated patients, irrespective of respiratory compliance and baseline intra-abdominal pressure values. End-expiratory measurements referenced against atmospheric pressure may suffice for clinical practice.

  3. High Blood Pressure

    Science.gov (United States)

    ... giving Gift and estate planning Circle of Champions Corporate sponsorship Join us at an event The Hope ... blood pressure is the #2 cause of kidney failure. It accounts for about one-fourth of all ...

  4. High Blood Pressure (Hypertension)

    Science.gov (United States)

    ... possible. Practice healthy coping techniques, such as muscle relaxation, deep breathing or meditation. Getting regular physical activity ... you monitor your blood pressure at home. Practice relaxation or slow, deep breathing. Practice taking deep, slow ...

  5. High Blood Pressure and Women

    Science.gov (United States)

    ... blood pressure during a previous pregnancy, have a family history of high blood pressure or mild kidney disease. The combination of birth ... Print (PDF) | Online How to Measure Your Blood Pressure (PDF) Questions To Ask ... FREE digital-only, quarterly magazine for patients, families, and caregivers, which focuses on the prevention and ...

  6. What Is High Blood Pressure?

    Science.gov (United States)

    ... Disease Venous Thromboembolism Aortic Aneurysm More What is High Blood Pressure? Updated:Oct 31,2016 First, let’s define high ... resources . This content was last reviewed October 2016. High Blood Pressure • Home • Get the Facts About HBP Introduction What ...

  7. Correlation study of intra-abdominal fat accumulation and ambulatory blood pressure

    Directory of Open Access Journals (Sweden)

    Li ZHANG

    2012-05-01

    Full Text Available Objective  To explore the influence of intra-abdominal fat (IAF accumulation on ambulatory blood pressure (ABP. Methods  Four hundred and forty-eight hospitalized patients with cardiovascular and metabolic diseases, including 235 males and 213 females, aged 20-85 (55±12 years old, were enrolled in this study. The abdominal fatty thickness was measured with B-mode ultrasound. Simultaneously the patient received 24hABP monitoring. The patients were divided into excessive IAF group, normal group, and quintile subgroups according to the cut-off points (male 38.5mm, female 34.7mm for observing the difference in indexes of ambulatory blood pressure between different groups/subgroups. Results  The 24h mean systolic BP (24hMSBP, 24h mean BP (24hMBP, 24h mean diastolic BP (24hMDBP, daytime MSBP (dMSBP, daytime MBP (dMBP, daytime MDBP (dMDBP, nighttime MSBP (nMSBP, nighttime MBP (nMBP, night MDBP (nMDBP were significantly higher in the excessive IAF group than in the normal group (P < 0.05. However, the elevation of ABP was not a simple gradual linear elevation corresponding to a gradual increase in IAF thickness, but manifested an approximately U-shaped trend. Pearson correlation analysis showed IAF thickness was positively correlated with all the indexes of 24hABP, while partial correlation analysis after adjustment for age and sex showed IAF thickness was positively correlated with 24hSBP, 24hMBP, dMBP and nMBP. Conclusion  The relationship between IAF thickness and ABP presents a U-shaped curve, which may provide an enlightenment in controlling blood pressure by weight loss in clinical work.

  8. Effect of intra-abdominal pressure on respiratory function in patients undergoing ventral hernia repair.

    Science.gov (United States)

    Gaidukov, Konstantin M; Raibuzhis, Elena N; Hussain, Ayyaz; Teterin, Alexey Y; Smetkin, Alexey A; Kuzkov, Vsevolod V; Malbrain, Manu Lng; Kirov, Mikhail Y

    2013-05-04

    To determine the influence of intra-abdominal pressure (IAP) on respiratory function after surgical repair of ventral hernia and to compare two different methods of IAP measurement during the perioperative period. Thirty adult patients after elective repair of ventral hernia were enrolled into this prospective study. IAP monitoring was performed via both a balloon-tipped nasogastric probe [intragastric pressure (IGP), CiMON, Pulsion Medical Systems, Munich, Germany] and a urinary catheter [intrabladder pressure (IBP), UnoMeterAbdo-Pressure Kit, UnoMedical, Denmark] on five consecutive stages: (1) after tracheal intubation (AI); (2) after ventral hernia repair; (3) at the end of surgery; (4) during spontaneous breathing trial through the endotracheal tube; and (5) at 1 h after tracheal extubation. The patients were in the complete supine position during all study stages. The IAP (measured via both techniques) increased on average by 12% during surgery compared to AI (P IGP and IBP (r = 0.65-0.81, P IGP was 8.0 (5.5-11.0) mmHg and the median IBP was 8.8 (5.8-13.1) mmHg. The overall r (2) value (n = 30) was 0.76 (P IGP or IBP demonstrated excellent concordance.

  9. Common High Blood Pressure Myths

    Science.gov (United States)

    ... Artery Disease Venous Thromboembolism Aortic Aneurysm More Common High Blood Pressure Myths Updated:Dec 9,2016 Knowing the facts ... health. This content was last reviewed October 2016. High Blood Pressure • Home • Get the Facts About HBP Introduction What ...

  10. Stroke and High Blood Pressure

    Science.gov (United States)

    ... More How High Blood Pressure Can Lead to Stroke Updated:Dec 2,2016 Stroke and high blood ... Changes That Matter • Find Tools & Resources Show Your Stroke Support! Show your stroke support with our new ...

  11. Nanomaterials under high-pressure.

    Science.gov (United States)

    San-Miguel, Alfonso

    2006-10-01

    The use of high-pressure for the study and elaboration of homogeneous nanostructures is critically reviewed. Size effects, the interaction between nanostructures and guest species or the interaction of the nanosystem with the pressure transmitting medium are emphasized. Phase diagrams and the possibilities opened by the combination of pressure and temperature for the elaboration of new nanomaterials is underlined through the examination of three different systems: nanocrystals, nano-cage materials which include fullerites and group-14 clathrates, and single wall nanotubes. This tutorial review is addressed to scientist seeking an introduction or a panoramic view of the study of nanomaterials under high-pressure.

  12. Intra-abdominal pressure alterations after large pancreatic pseudocyst transcutaneous drainage

    Directory of Open Access Journals (Sweden)

    Papavramidis Theodossis S

    2009-06-01

    Full Text Available Abstract Background Acute pancreatitis leads to abdominal hypertension and compartment syndrome. Weeks after the episodes pancreatic fluids sometimes organize to pseudocysts, fluid collections by or in the gland. Aims of the present study were to evaluate the intra-abdominal pressure (IAP induced by large pancreatic pseudocysts and to examine the effect of their transcutaneous drainage on IAP. Methods Twenty seven patients with a pancreatic pseudocyst were included. Nine patients with pseudocysts greater than 1l (group A had CT drainage and eighteen (volume less than 1l were the control group. The measurements of group A were taken 6 hours before and every morning after the drainage, while for group B, two measurements were performed, one at the day of the initial CT and one 7 days after. Abdominal compliance (Cabd was calculated. Data were analyzed using student's t-test. Results Baseline IAP for group A was 9.3 mmHg (S.D. 1.7 mmHg, while the first post-drainage day (PDD IAP was 5.1 mmHg (S.D. 0.7 mmHg. The second PDD IAP was 5.6 mmHg (S.D. 0.8 mmHg, the third 6.4 mmH (S.D. 1.2 mmHgg, the fourth 6.9 mmHg (S.D. 1.6 mmHg, the fifth 7.9 mmHg (S.D. 1.5 mmHg, the sixth 8.2 mmHg (S.D. 1.4 mmHg, and the seventh 8.2 mmHg (S.D. 1.5 mmHg. Group B had baseline IAP 8.0 mmHg (S.D. 1.2 mmHg and final 8.2 mmHg (S.D. 1.4 mmHg. Cabd after drainage was 185.6 ml/mmHg (SD 47.5 ml/mmHg. IAP values were reduced between the baseline and all the post-drainage measurements in group A. IAPs seem to stabilize after the 5th post-drainage day. Baseline IAP was higher in group A than in group B, while the two values, at day 7, were equivalent. Conclusion The drainage of large pancreatic pseudocyst reduces IAP. Moreover, the IAP seems to rise shortly after the drainage again, but in a way that it remains inferior to the initial value. More chronic changes to the IAP are related to abdominal cavity's properties and have to be further studied.

  13. High-Pressure Vibrational Spectroscopy.

    Science.gov (United States)

    Pogson, Mark

    1987-09-01

    Available from UMI in association with The British Library. Requires signed TDF. The study of solids at high pressure and variable temperature enables development of accurate interatomic potential functions over wide ranges of interatomic distances. A review of the main models used in the determination of these potentials is given in Chapter one. A discussion of phonon frequency as a variable physical parameter reflecting the interatomic potential is given. A high pressure Raman study of inorganic salts of the types MSCN, (M = K,Rb,Cs & NH_4^+ ) and MNO_2, (M = K,Na) has been completed. The studies have revealed two new phases in KNO_2 and one new phase in NaNO _2 at high pressure. The accurate phonon shift data have enabled the determination of the pure and biphasic stability regions of the phases of KNO _2. A discussion of the B1, B2 relationship of univalent nitrites is also given. In the series of thiocyanates studied new phases have been found in all four materials. In both the potassium and rubidium salts two new phases have been detected, and in the ceasium salt one new phase has been detected, all at high pressure, from accurate phonon shift data. These transitions are discussed in terms of second-order mechanisms with space groups suggested for all phases, based on Landau's theory of second-order phase transitions. In the ammonium salt one new phase has been detected. This new phase transition has been interpreted as a second-order transition. The series of molecular crystals CH_3 HgX, (X = Cl,Br & I) has been studied at high pressure and at variable temperature. In Chapter five, their phase behaviour at high pressure is detailed along with the pressure dependencies of their phonon frequencies. In the chloride and the bromide two new phases have been detected. In the bromide one has been detected at high temperature and one at high pressure, and latter being interpreted as the stopping of the methyl rotation. In the chloride one phase has been found at

  14. Clinical evaluation of an air-capsule technique for the direct measurement of intra-abdominal pressure after elective abdominal surgery

    Science.gov (United States)

    Otto, Jens; Kaemmer, Daniel; Biermann, Andreas; Jansen, Marc; Dembinski, Rolf; Schumpelick, Volker; Schachtrupp, Alexander

    2008-01-01

    Background The gold standard for assessment of intraabdominal pressure (IAP) is via intravesicular pressure measurement (IVP). This accepted technique has some inherent problems, e.g. indirectness. Aim of this clinical study was to assess direct IAP measurement using an air-capsule method (ACM) regarding complications risks and agreement with IVP in patients undergoing abdominal surgery. Methods A prospective cohort study was performed in 30 patients undergoing elective colonic, hepatic, pancreatic and esophageal resection. For ACM a Probe 3 (Spiegelberg®, Germany) was placed on the greater omentum. It was passed through the abdominal wall paralleling routine drainages. To compare ACM with IVP t-testing was performed and mean difference as well as limits of agreement were calculated. Results ACM did not lead to complications particularly with regard to organ lesion or surgical site infection. Mean insertion time of ACM was 4.4 days (min-max: 1–5 days). 168 pairwise measurements were made. Mean ACM value was 7.9 ± 2.7 mmHg while mean IVP was 8.4 ± 3.0 mmHg (n.s). Mean difference was 0.4 mmHg ± 2.2 mmHg. Limits of agreement were -4.1 mmHg to 5.1 mmHg. Conclusion Using ACM, direct IAP measurement is feasible and uncomplicated. Associated with relatively low pressure ranges (<17 mmHg), results are comparable to bladder pressure measurement. PMID:18925973

  15. Raman Spectroscopy at High Pressures

    Directory of Open Access Journals (Sweden)

    Alexander F. Goncharov

    2012-01-01

    Full Text Available Raman spectroscopy is one of the most informative probes for studies of material properties under extreme conditions of high pressure. The Raman techniques have become more versatile over the last decades as a new generation of optical filters and multichannel detectors become available. Here, recent progress in the Raman techniques for high-pressure research and its applications in numerous scientific disciplines including physics and chemistry of materials under extremes, earth and planetary science, new materials synthesis, and high-pressure metrology will be discussed.

  16. Steam Oxidation at High Pressure

    Energy Technology Data Exchange (ETDEWEB)

    Holcomb, Gordon R. [NETL; Carney, Casey [URS

    2013-07-19

    A first high pressure test was completed: 293 hr at 267 bar and 670{degrees}C; A parallel 1 bar test was done for comparison; Mass gains were higher for all alloys at 267 bar than at 1 bar; Longer term exposures, over a range of temperatures and pressures, are planned to provide information as to the commercial implications of pressure effects; The planned tests are at a higher combination of temperatures and pressures than in the existing literature. A comparison was made with longer-term literature data: The short term exposures are largely consistent with the longer-term corrosion literature; Ferritic steels--no consistent pressure effect; Austenitic steels--fine grain alloys less able to maintain protective chromia scale as pressure increases; Ni-base alloys--more mass gains above 105 bar than below. Not based on many data points.

  17. Effect of Low-Pressurized Perfusion with Different Concentration of Elastase on the Aneurysm Formation Rate in the Abdominal Aortic Aneurysm Model in Rabbits.

    Science.gov (United States)

    Nie, Maoxiao; Yan, Yunfeng; Li, Xinhe; Feng, Tingting; Zhao, Xin; Zhang, Mingduo; Zhao, Quanming

    2016-01-01

    Establishing an animal model of abdominal aortic aneurysm (AAA) is the key to study the pathogenesis and the pathophysiological features of AAAs. We investigated the effects of low-pressurized perfusion with different concentrations of elastase on aneurysm formation rate in the AAA model. Fifty male New Zealand white rabbits were randomly divided into A, B, C, D, and E groups. 10 μL of normal saline was perfused into the abdominal aorta in group A and 1 U/mL, 10 U/mL, 100 U/mL, or 200 U/mL of elastase was, respectively, perfused for the other four groups. All the animals were perfused for 7 min. Doppler ultrasound examinations of the abdominal aorta were performed before surgery and on day 14 after surgery. The rabbits were sacrificed and the perfused segment of the abdominal aorta was observed visually and after staining. The aneurysm formation rate of group A, group B, group C, group D, and group E was, respectively, 0%, 0%, 33.3%, 102.5-146.8%, and 241.5-255.2%. The survival rate of five groups was 90%, 90%, 90%, 90%, and 40%, respectively. So, we concluded that low-pressurized perfusion with 100 U/mL of elastase can effectively establish AAAs in rabbits with a high aneurysm formation rate.

  18. High Blood Pressure Prevention

    Science.gov (United States)

    ... or "no added salt." Look for the sodium content in milligrams and the Percent Daily Value. Aim for foods that are less than 5 percent of the Daily Value of sodium. Foods with 20 percent or more Daily Value of sodium are considered high. To learn more about reading nutrition labels, see ...

  19. Hypertension (High Blood Pressure)

    Science.gov (United States)

    ... over the years led to verification of the important role of high blood pressure—especially in concert with ... is specific for that person will be an important key to improving prevention, ... an international team of investigators, funded in part by the NIH, ...

  20. High pressure ceramic joint

    Science.gov (United States)

    Ward, Michael E.; Harkins, Bruce D.

    1993-01-01

    Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present joint when used with recuperators increases the use of ceramic components which do not react to highly corrosive gases. Thus, the present joint used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present joint is comprised of a first ceramic member, a second ceramic member, a mechanical locking device having a groove defined in one of the first ceramic member and the second ceramic member. The joint and the mechanical locking device is further comprised of a refractory material disposed in the groove and contacting the first ceramic member and the second ceramic member. The present joint mechanically provides a high strength load bearing joint having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures.

  1. Diagnosis of High Blood Pressure

    Medline Plus

    Full Text Available ... Planning, & Legislative Advisory Committees Jobs Contact Us FAQs Home » Health Information for the Public » Health Topics » High ... also may ask you to check readings at home or at other locations that have blood pressure ...

  2. Diagnosis of High Blood Pressure

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    Full Text Available ... Explore High Blood Pressure What Is... Other Names Causes Who Is at Risk Signs & Symptoms Diagnosis Treatments Prevention Living With Clinical Trials Links Related Topics Atherosclerosis DASH Eating Plan Overweight and Obesity Smoking and Your Heart ...

  3. Diagnosis of High Blood Pressure

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    Full Text Available ... Health care providers diagnose this type of high blood pressure by reviewing readings in the office and readings taken anywhere else. ... The Heart Truth ® —a national heart disease awareness campaign for ...

  4. Diagnosis of High Blood Pressure

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    Full Text Available ... to check readings at home or at other locations that have blood pressure equipment and to keep ... office compared with readings taken in any other location. Health care providers diagnose this type of high ...

  5. Diagnosis of High Blood Pressure

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    Full Text Available ... provider usually takes 2–3 readings at several medical appointments to diagnose high blood pressure. Using the ... Researchers believe stress, which can occur during the medical appointment, causes white coat hypertension. Rate This Content: ...

  6. Diagnosis of High Blood Pressure

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    Full Text Available ... Events Spokespeople Email Alerts E-Newsletters About NHLBI Organization NHLBI Director Budget, Planning, & Legislative Advisory Committees Jobs Contact Us FAQs Home » Health Information for the Public » Health Topics » High Blood Pressure » ...

  7. High pressure rinsing parameters measurements

    Energy Technology Data Exchange (ETDEWEB)

    Cavaliere, E. [INFN Milano - LASA, Via F.lli Cervi 201, I-20090 Segrate (MI) (Italy); Fusetti, M. [INFN Milano - LASA, Via F.lli Cervi 201, I-20090 Segrate (MI) (Italy); Michelato, P. [INFN Milano - LASA, Via F.lli Cervi 201, I-20090 Segrate (MI) (Italy); Pagani, C. [INFN Milano - LASA, Via F.lli Cervi 201, I-20090 Segrate (MI) (Italy)]. E-mail: carlo.pagani@mi.infn.it; Pierini, P. [INFN Milano - LASA, Via F.lli Cervi 201, I-20090 Segrate (MI) (Italy); Paulon, R. [INFN Milano - LASA, Via F.lli Cervi 201, I-20090 Segrate (MI) (Italy); Sertore, D. [INFN Milano - LASA, Via F.lli Cervi 201, I-20090 Segrate (MI) (Italy)

    2006-07-15

    High pressure rinsing with ultra pure water jet is an essential step in the high field superconducting cavity production process. In this paper, we illustrate the experimental characterization of a HPR system, in terms of specific power and energy deposition on the cavity surfaces and on the damage threshold for niobium. These measurements are used to tentatively derive general rules for the optimization of the free process parameters (nozzle geometry, speeds and water pressure)

  8. Clinical evaluation of an air-capsule technique for the direct measurement of intra-abdominal pressure after elective abdominal surgery

    Directory of Open Access Journals (Sweden)

    Dembinski Rolf

    2008-10-01

    Full Text Available Abstract Background The gold standard for assessment of intraabdominal pressure (IAP is via intravesicular pressure measurement (IVP. This accepted technique has some inherent problems, e.g. indirectness. Aim of this clinical study was to assess direct IAP measurement using an air-capsule method (ACM regarding complications risks and agreement with IVP in patients undergoing abdominal surgery. Methods A prospective cohort study was performed in 30 patients undergoing elective colonic, hepatic, pancreatic and esophageal resection. For ACM a Probe 3 (Spiegelberg®, Germany was placed on the greater omentum. It was passed through the abdominal wall paralleling routine drainages. To compare ACM with IVP t-testing was performed and mean difference as well as limits of agreement were calculated. Results ACM did not lead to complications particularly with regard to organ lesion or surgical site infection. Mean insertion time of ACM was 4.4 days (min-max: 1–5 days. 168 pairwise measurements were made. Mean ACM value was 7.9 ± 2.7 mmHg while mean IVP was 8.4 ± 3.0 mmHg (n.s. Mean difference was 0.4 mmHg ± 2.2 mmHg. Limits of agreement were -4.1 mmHg to 5.1 mmHg. Conclusion Using ACM, direct IAP measurement is feasible and uncomplicated. Associated with relatively low pressure ranges (

  9. Effect of increased intra-abdominal pressure due to pneumoperitoneum on liver functions and liver histopathology in a rat model with intra-abdominal sepsis.

    Science.gov (United States)

    Youssef, Youssef Farouk; Noseer, Mona

    2008-04-01

    Intra-abdominal sepsis was induced by open cecal ligation and puncture (OCLP) technique. Sixty rats were randomly divided into three equal groups each of 20. G1 was used as a control. G2 were subjected to laparotomy and closure after 12 hours from (OCLP) via the same incision. In G3, pneumoperitoneum was induced 12 hours after OCLP and maintained at 12 mmHg for about 30 minutes. Blood samples were taken for liver functions after 12 & 24 hours from OCLP procedure, and Liver biopsies were taken for histopathological examination after 24 hours. The results showed that liver functions were markedly increased in G3 after pneumoperitoneum, compared to Gs 1 & 2. The histopathological changes in liver biopsies due to sepsis were more marked in cases exposed to pneumoperitoneum than that exposed to conventional laparotomy. The intra-abdominal sepsis affected liver functions and caused pathogenesis. The increased intra-abdominal pressure induced more liver insults, compared to that gained after open surgery.

  10. Intra-abdominal pressure during Pilates: unlikely to cause pelvic floor harm.

    Science.gov (United States)

    Coleman, Tanner J; Nygaard, Ingrid E; Holder, Dannielle N; Egger, Marlene J; Hitchcock, Robert

    2015-08-01

    The objective was to describe the intra-abdominal pressures (IAP) generated during Pilates Mat and Reformer activities, and determine whether these activities generate IAP above a sit-to-stand threshold. Twenty healthy women with no symptomatic vaginal bulge, median age 43 (range 22-59 years), completed Pilates Mat and Reformer exercise routines each consisting of 11 exercises. IAP was collected by an intra-vaginal pressure transducer, transmitted wirelessly to a base station, and analyzed for maximal and area under the curve (AUC) IAP. There were no statistically significant differences in the mean maximal IAP between sit-to-stand and any of the Mat or Reformer exercises in the study population. Six to twenty-five percent of participants exceeded their individual mean maximal IAP sit-to-stand thresholds for 10 of the 22 exercises. When measuring AUC from 0 cm H2O, half the exercises exceeded the mean AUC of sit-to-stand, but only Pilates Reformer and Mat roll-ups exceeded the mean AUC of sit-to-stand when calculated from a threshold of 40 cm H2O (consistent with, for example, walking). Our results support recommending this series of introductory Pilates exercises, including five Mat exercises and six Reformer exercises to women desiring a low IAP exercise routine. More research is needed to determine the long-term effects of Pilates exercise on post-surgical exercise rehabilitation and pelvic floor health.

  11. Hemorrhage exacerbates bacterial translocation at low levels of intra-abdominal pressure.

    Science.gov (United States)

    Gargiulo, N J; Simon, R J; Leon, W; Machiedo, G W

    1998-12-01

    It has been shown previously that the adverse cardiopulmonary sequelae of increased intra-abdominal pressure (IAP) are worsened by hemorrhage and resuscitation. Bacterial translocation (BT) to the mesenteric lymph nodes (MLNs), liver, and spleen has also been shown to occur with increased IAP. To investigate the hypothesis that BT associated with elevated IAP would be significantly increased after hemorrhage and resuscitation. Anesthetized adult male rats had femoral artery and vein catheters placed, and an intra-abdominal catheter placed to measure IAP. Group 1 underwent surgery only and served as controls. Group 2 had IAP raised to 10 mm Hg by infused lactated Ringer's solution for 40 minutes. Group 3 had a 25% hemorrhage, followed by resuscitation by infused lactated Ringer's solution and shed blood. Group 4 first had a 25% hemorrhage, resuscitated using infused lactated Ringer's solution and shed blood, and then had IAP raised to 10 mm Hg by infused lactated Ringer's solution for 40 minutes. All groups were killed after 2 hours, and had MLNs, liver, and spleen harvested for quantitative cultures. Hemorrhage and resuscitation alone did not increase BT to the MLNs, liver, or spleen. An increase in IAP to 10 mm Hg resulted in a significant level of BT to the MLNs and liver on MacConkey II agar (PBT only to the liver on trypticase soy agar with 5% sheep's blood (PBT to the liver and spleen when IAP was increased to 10 mm Hg (PBT to the MLNs, liver, or spleen. However, hemorrhage and resuscitation increased BT to the liver and spleen when IAP was increased to 10 mm Hg. This supports the concept that prior hemorrhage and resuscitation exacerbates the effects of increased IAP.

  12. High-pressure creep tests

    Science.gov (United States)

    Bhattacharyya, S.; Lamoureux, J.; Hales, C.

    1986-01-01

    The automotive Stirling engine, presently being developed by the U.S. Department of Energy and NASA, uses high-pressure hydrogen as a working fluid; its long-term effects on the properties of alloys are relatively unknown. Hence, creep-rupture testing of wrought and cast high-temperature alloys in high-pressure hydrogen is an essential part of the research supporting the development of the Stirling cycle engine. Attention is given to the design, development, and operation of a 20 MPa hydrogen high-temperature multispecimen creep-rupture possessing high sensitivity. This pressure vessel allows for the simultaneous yet independent testing of six specimens. The results from one alloy, XF-818, are presented to illustrate how reported results are derived from the raw test data.

  13. Perforated second trimester appendicitis with abdominal compartment syndrome managed with negative pressure wound therapy and open abdomen.

    Science.gov (United States)

    Turnock, Adam R; Fleischer, Brian P; Carney, Martin J; Vanderlan, Wesley B

    2016-06-14

    Abdominal compartment syndrome (ACS) is a known complication of laparotomy; however, the literature is lacking in regards to treatment of this entity in pregnant patients. We present a case of acute perforated appendicitis in a second trimester primagravida, complicated by gangrenous necrosis of the contiguous bowel with subsequent development of ACS and intra-abdominal sepsis. This was treated with a novel approach, using non-commercial negative pressure wound therapy and open abdomen technique. Gestational integrity was preserved and the patient went on to experience a normal spontaneous vaginal delivery. At 5 years post-delivery the patient has had no surgical complications and her baby has met all developmental milestones.

  14. High pressure neon arc lamp

    Science.gov (United States)

    Sze, Robert C.; Bigio, Irving J.

    2003-07-15

    A high pressure neon arc lamp and method of using the same for photodynamic therapies is provided. The high pressure neon arc lamp includes a housing that encloses a quantity of neon gas pressurized to about 500 Torr to about 22,000 Torr. At each end of the housing the lamp is connected by electrodes and wires to a pulse generator. The pulse generator generates an initial pulse voltage to breakdown the impedance of the neon gas. Then the pulse generator delivers a current through the neon gas to create an electrical arc that emits light having wavelengths from about 620 nanometers to about 645 nanometers. A method for activating a photosensitizer is provided. Initially, a photosensitizer is administered to a patient and allowed time to be absorbed into target cells. Then the high pressure neon arc lamp is used to illuminate the target cells with red light having wavelengths from about 620 nanometers to about 645 nanometers. The red light activates the photosensitizers to start a chain reaction that may involve oxygen free radicals to destroy the target cells. In this manner, a high pressure neon arc lamp that is inexpensive and efficiently generates red light useful in photodynamic therapy is provided.

  15. Differential Effects of Intraoperative Positive End-expiratory Pressure (PEEP) on Respiratory Outcome in Major Abdominal Surgery Versus Craniotomy

    DEFF Research Database (Denmark)

    de Jong, Myrthe A C; Ladha, Karim S; Melo, Marcos F Vidal

    2015-01-01

    OBJECTIVES: In this study, we examined whether (1) positive end-expiratory pressure (PEEP) has a protective effect on the risk of major postoperative respiratory complications in a cohort of patients undergoing major abdominal surgeries and craniotomies, and (2) the effect of PEEP is differed...... abdominal surgery patients and 5063 craniotomy patients. Analysis was performed using multivariable logistic regression. The primary outcome was a composite of major postoperative respiratory complications (respiratory failure, reintubation, pulmonary edema, and pneumonia) within 3 days of surgery. RESULTS...... odds of respiratory complications in patients undergoing major abdominal surgery (odds ratio 0.53, 95% confidence interval 0.39 - 0.72), effects that translated to deceased hospital length of stay [median hospital length of stay : 6 days (4-9 days), incidence rate ratios for each additional day: 0...

  16. In vitro pressure manifolding distribution evaluation of ABThera™ Active Abdominal Therapy System, V.A.C.® Abdominal Dressing System, and Barker’s vacuum packing technique conducted under dynamic conditions

    Directory of Open Access Journals (Sweden)

    Angel Delgado

    2016-01-01

    Full Text Available Objectives: Temporary abdominal closure methods allow for management of open abdomens where immediate primary closure is not possible and/or where repeat abdominal entries are necessary. We assessed pressure mapping and fluid extraction efficiency of three open abdomen dressing systems: ABThera™ Active Abdominal Therapy System, V.A.C.® Abdominal Dressing System, and Barker’s vacuum packing technique. Methods: An in vitro test model was designed to simulate physical conditions present in an open abdomen. The model consisted of a rigid rest platform with elevated central region and a flexible outer layer with centrally located incision. Constant −125 mmHg negative pressure was applied according to the type of system, under simulated dynamic conditions, using albumin-based solution with a viscosity of 14 cP. Data were collected by pressure sensors located circumferentially into three concentric zones: Zone 1 (closest to negative pressure source, Zone 2 (immediately outside of manifolding material edge, and Zone 3 (area most distal from negative pressure source. Each value was the result of approximately 100 pressure readings/zone/experiment with a total of three experiments for each system. Results: Pressure distribution of ABThera Therapy was significantly (p < 0.05 superior to Barker’s vacuum packing technique in all three evaluated zones. Similarly, V.A.C. Abdominal Dressing System pressure distribution was significantly (p < 0.05 improved compared to Barker’s vacuum packing technique in all zones. There were no pressure distribution differences in Zone 1 between ABThera Therapy and V.A.C. Abdominal Dressing System; however, in Zones 2 and 3, ABThera Therapy was significantly (p < 0.05 superior to V.A.C. Abdominal Dressing System. Conclusions: These data suggest that all approaches to negative pressure therapy for open abdomen treatment are not equal. Additional research should be conducted to elucidate clinical

  17. Mass or high-risk screening for abdominal aortic aneurysm

    DEFF Research Database (Denmark)

    Lindholt, Jes Sanddal; Henneberg, E W; Fasting, H

    1997-01-01

    Abdominal aortic aneurysm (AAA) is known to be associated with various diseases, especially hypertension, acute myocardial infarction (AMI), chronic obstructive airway disease (COAD), and intermittent claudication. These associations have led to a debate about whether screening of older men for AAA...

  18. High heritability of liability to abdominal aortic aneurysms

    DEFF Research Database (Denmark)

    Mejnert Jørgensen, Trine; Christensen, Kaare; Lindholt, Jes Sanddal

    2016-01-01

    OBJECTIVE: First degree relatives of patients with abdominal aortic aneurysm (AAA) have an increased risk of developing AAA; however, despite intensive investigation, the specific genetic factors involved in the development of the disease are still largely unknown. In twin studies the influence...

  19. High heritability of liability to abdominal aortic aneurysms

    DEFF Research Database (Denmark)

    Mejnert Jørgensen, Trine; Houlind, Kim Christian; Christensen, Kaare;

    2016-01-01

    OBJECTIVE: First degree relatives of patients with abdominal aortic aneurysm (AAA) have an increased risk of developing AAA; however, despite intensive investigation, the specific genetic factors involved in the development of the disease are still largely unknown. In twin studies the influence o...

  20. Mass or high-risk screening for abdominal aortic aneurysm

    DEFF Research Database (Denmark)

    Lindholt, Jes Sanddal; Henneberg, E W; Fasting, H

    1997-01-01

    Abdominal aortic aneurysm (AAA) is known to be associated with various diseases, especially hypertension, acute myocardial infarction (AMI), chronic obstructive airway disease (COAD), and intermittent claudication. These associations have led to a debate about whether screening of older men for AAA...

  1. Evidence for Negative Effects of Elevated Intra-Abdominal Pressure on Pulmonary Mechanics and Oxidative Stress

    Directory of Open Access Journals (Sweden)

    I. Davarcı

    2015-01-01

    Full Text Available Objective. To compare the effects of pneumoperitoneum on lung mechanics, end-tidal CO2 (ETCO2, arterial blood gases (ABG, and oxidative stress markers in blood and bronchoalveolar lavage fluid (BALF during laparoscopic cholecystectomy (LC by using lung-protective ventilation strategy. Materials and Methods. Forty-six patients undergoing LC and abdominal wall hernia (AWH surgery were assigned into 2 groups. Measurements and blood samples were obtained before, during pneumoperitoneum, and at the end of surgery. BALF samples were obtained after anesthesia induction and at the end of surgery. Results. Peak inspiratory pressure, ETCO2, and pCO2 values at the 30th minute were significantly increased, while there was a significant decrease in dynamic lung compliance, pH, and pO2 values in LC group. In BALF samples, total oxidant status (TOS, arylesterase, paraoxonase, and malondialdehyde levels were significantly increased; the glutathione peroxidase levels were significantly decreased in LC group. The serum levels of TOS and paraoxonase were significantly higher at the end of surgery in LC group. In addition, arylesterase level in the 30th minute was increased compared to baseline. Serum paraoxonase level at the end of surgery was significantly increased when compared to AWH group. Conclusions. Our study showed negative effects of pneumoperitoneum in both lung and systemic levels despite lung-protective ventilation strategy.

  2. Intermolecular Interactions at high pressure

    DEFF Research Database (Denmark)

    Eikeland, Espen Zink

    2016-01-01

    In this project high-pressure single crystal X-ray diffraction has been combined with quantitative energy calculations to probe the energy landscape of three hydroquinone clathrates enclosing different guest molecules. The simplicity of the hydroquinone clathrate structures together with their st......In this project high-pressure single crystal X-ray diffraction has been combined with quantitative energy calculations to probe the energy landscape of three hydroquinone clathrates enclosing different guest molecules. The simplicity of the hydroquinone clathrate structures together...... with their structural chemistry, controlled largely by subtle interactions between the host and the enclosed guest molecules, makes them attractive to study as model systems. Quantifying the numerous superimposed interactions in these clathrates will advance our understanding of more complex supramolecular aggregates....... High-pressure crystallography is the perfect method for studying intermolecular interactions, by forcing the molecules closer together. In all three studied hydroquinone clathrates, new pressure induced phase transitions have been discovered using a mixture of pentane and isopentane as the pressure...

  3. Routine enema before urodynamics has no impact on the quality of abdominal pressure curves: Results of a prospective controlled study.

    Science.gov (United States)

    Rigole, H; Senal, N; Damphousse, M; Brochard, C; Manunta, A; Kerdraon, J; Tondut, L; Alimi, Q; Hascoet, J; Siproudhis, L; Peyronnet, B; Bonan, I

    2016-12-01

    The presence of stools in the rectum might affect the quality of the abdominal pressure curve during filling cystometry, but, to date, no study has evaluated the impact of bowel preparation before urodynamics. We evaluated the influence of a sodium phosphate enema before urodynamics on the quality of the abdominal pressure curve. A prospective, controlled, single-blind study was conducted in a single center from May to June 2013. The patients were divided into 2 consecutive groups: patients seen in outpatient clinics during the first 6 weeks (group A) who underwent urodynamics without bowel preparation and patients seen in outpatient clinics during the second 6 weeks (group B) who had a prescription of sodium phosphate enema before urodynamics. The primary endpoint was the quality of the abdominal pressure curve evaluated independently by three physicians who were blinded to the study group. The following data were also collected: age, gender, the presence of a neurological disorder, complicated nature of urodynamics and bother related to preparation for it, assessed using a Likert scale (0 to 10), and the equipment used. A per protocol analysis and an intent-to-treat analysis were conducted. One hundred and thirty-nine patients were included: 54 in group A and 85 in group B. One-third of patients had neurological conditions. 14 patients in group B did not perform their scheduled enema. Thus, 68 patients performed an enema before urodynamics and 71 did not. There was no difference between groups A and B regarding the complicated nature of urodynamics (Likert scale: 3.12 vs. 3.18; P=0.91) or bother related to preparation for it (Likert scale: 3.46 vs. 2.97; P=0.43). In the per protocol analysis, the abdominal pressure curve was considered perfectly interpretable (PI) in 69% of patients who did not receive an enema before urodynamics and in 65% of patients who did (P=0.61). The between-group difference was not statistically significant in intent-to-treat analysis (P

  4. High Blood Pressure and Kidney Disease

    Science.gov (United States)

    ... Disease Mineral & Bone Disorder View All Content High Blood Pressure & Kidney Disease What is high blood pressure? Blood pressure is the force of blood ... million filtering units called nephrons. How does high blood pressure affect the kidneys? High blood pressure can ...

  5. Anxiety: A Cause of High Blood Pressure?

    Science.gov (United States)

    ... Conditions High blood pressure (hypertension) Can anxiety cause high blood pressure? Answers from Sheldon G. Sheps, M.D. Anxiety doesn't cause long-term high blood pressure (hypertension). But episodes of anxiety can cause dramatic, ...

  6. High Blood Pressure Often Undiagnosed, Untreated

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_162996.html High Blood Pressure Often Undiagnosed, Untreated Half of mobile clinic patients ... that's often referred to as a "silent killer" -- high blood pressure, a new Canadian study reveals. High blood pressure, ...

  7. Localised abdominal compartment syndrome: bladder-over-gastric pressure ratio (B/G ratio) as a clue to diagnosis.

    Science.gov (United States)

    Malbrain, M L N G; De Laet, I E; Willems, A; Van Regenmortel, N; Schoonheydt, K; Dits, H

    2010-01-01

    Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) have been identified as a cause of organ dysfunction and mortality in critically ill patients. The diagnosis of IAH/ACS depends on accurate intra-abdominal pressure (IAP) measurement, which is usually performed via the bladder or the stomach.The aim of this study was to describe cases where intragastric pressure (IGP) and intrabladder pressure (IBP) were measured simultaneously. After review of medical records, four patients admitted to our ICU department where both IGP and IBP were measured, could be identified. IGP was measured using the Spiegelberg catheter and IBP was measured using the FoleyManometer LV. In all patients, the bladder-over-gastric pressure ratio (B/G ratio) was calculated. In two of four patients, IGP and IBP differed significantly. In one patient the B/G ratio was lower than 1 suggesting a diagnosis of epigastric ACS and in one patient B/G ratio was greater than 1 leading to a diagnosis of pelvic ACS. The latter patient was spared a decompressive laparotomy due to the additional IGP measurement and the subsequent diagnosis of localized ACS. The preferred methods for IAP measurement are via the bladder and via the stomach. In some patients, IGP and IBP may differ significantly and this may have clinical implications. Clinicians should be aware of the possibility of localized ACS. In order to identify risk factors and to recommend treatment for localized ACS, further study of simultaneous IGP and IBP measurements are needed.

  8. A systematic review on intra-abdominal pressure in severely burned patients

    NARCIS (Netherlands)

    K.D. Strang; E.M.M. van Lieshout (Esther); R.S. Breederveld (Roelf S.); O.J.F. van Waes (Oscar)

    2014-01-01

    textabstractObjective Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are complications that may occur in severely burned patients. Evidenced based medicine for these patients is in its early development. The aim of this study was to provide an overview of literature rega

  9. Vital Signs - High Blood Pressure

    Centers for Disease Control (CDC) Podcasts

    2012-10-02

    In the U.S., nearly one third of the adult population have high blood pressure, the leading risk factor for heart disease and stroke - two of the nation's leading causes of death.  Created: 10/2/2012 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 10/17/2012.

  10. Diagnosis of High Blood Pressure

    Medline Plus

    Full Text Available ... any other location. Health care providers diagnose this type of high blood pressure by reviewing readings in the office and readings taken anywhere else. Researchers believe stress, which can occur during the medical appointment, causes white coat hypertension. Rate This Content: NEXT >> Updated: ...

  11. Diagnosis of High Blood Pressure

    Medline Plus

    Full Text Available ... Explore High Blood Pressure What Is... Other Names Causes Who Is at Risk Signs & Symptoms Diagnosis Treatments Prevention Living With Clinical Trials Links Related Topics Atherosclerosis DASH Eating Plan Overweight and Obesity Smoking and Your Heart Stroke Send a link ...

  12. High Pressure Treatment in Foods.

    Science.gov (United States)

    Bello, Edwin Fabian Torres; Martínez, Gerardo González; Ceberio, Bernadette F Klotz; Rodrigo, Dolores; López, Antonio Martínez

    2014-08-19

    High hydrostatic pressure (HHP), a non-thermal technology, which typically uses water as a pressure transfer medium, is characterized by a minimal impact on food characteristics (sensory, nutritional, and functional). Today, this technology, present in many food companies, can effectively inactivate bacterial cells and many enzymes. All this makes HHP very attractive, with very good acceptance by consumers, who value the organoleptic characteristics of products processed by this non-thermal food preservation technology because they associate these products with fresh-like. On the other hand, this technology reduces the need for non-natural synthetic additives of low consumer acceptance.

  13. High Pressure Treatment in Foods

    Directory of Open Access Journals (Sweden)

    Edwin Fabian Torres Bello

    2014-08-01

    Full Text Available High hydrostatic pressure (HHP, a non-thermal technology, which typically uses water as a pressure transfer medium, is characterized by a minimal impact on food characteristics (sensory, nutritional, and functional. Today, this technology, present in many food companies, can effectively inactivate bacterial cells and many enzymes. All this makes HHP very attractive, with very good acceptance by consumers, who value the organoleptic characteristics of products processed by this non-thermal food preservation technology because they associate these products with fresh-like. On the other hand, this technology reduces the need for non-natural synthetic additives of low consumer acceptance.

  14. High pressure rinsing system comparison

    Energy Technology Data Exchange (ETDEWEB)

    D. Sertore; M. Fusetti; P. Michelato; Carlo Pagani; Toshiyasu Higo; Jin-Seok Hong; K. Saito; G. Ciovati; T. Rothgeb

    2007-06-01

    High pressure rinsing (HPR) is a key process for the surface preparation of high field superconducting cavities. A portable apparatus for the water jet characterization, based on the transferred momentum between the water jet and a load cell, has been used in different laboratories. This apparatus allows to collected quantitative parameters that characterize the HPR water jet. In this paper, we present a quantitative comparison of the different water jet produced by various nozzles routinely used in different laboratories for the HPR process

  15. High Blood Pressure: Unique to Older Adults

    Science.gov (United States)

    ... our e-newsletter! Aging & Health A to Z High Blood Pressure Hypertension Unique to Older Adults This section provides ... Pressure Targets are Different for Very Old Adults High blood pressure (also called hypertension) increases your chance of having ...

  16. High pressure processing of meat

    DEFF Research Database (Denmark)

    Grossi, Alberto; Christensen, Mette; Ertbjerg, Per

    in the myofibrillar protein pattern and HP-induced change in activity of cathepsin B and L were investigated. Results: In this study we showed that HP treatment of pork meat emulsion, ranging from 0.1 to 800 MPa, induced protein gel formation as shown by the increased Young’s modulus (Fig.1). Analysis of SDS...... the rheological properties of pork meat batters by inducing formation of protein gels. HP induced protein gels are suggested to be formed by high molecular weight myofibrillar protein aggregates and by peptides formed by lysosomal enzyme-induced cleavage of myofibrillar proteins. Perspectives: The data presented......Abstract Background: The research of high pressure (HP) processing of meat based foods needs to address how pressure affects protein interactions, aggregation and/or gelation. The understanding of the gel forming properties of myofibrillar components is fundamental for the development of muscle...

  17. Management of the open abdomen using negative pressure wound therapy with instillation in severe abdominal sepsis

    Directory of Open Access Journals (Sweden)

    Pablo Sibaja

    2017-01-01

    NPWT-I in patients with severe abdominal sepsis had promising results, since we obtained higher fascia closure rates, lower mortality and reduced hospital and ICU length of stay with no complications due to this therapeutic approach.

  18. Insulin resistance, low cardiorespiratory fitness, and increased exercise blood pressure: contribution of abdominal obesity.

    Science.gov (United States)

    Huot, Maxime; Arsenault, Benoit J; Gaudreault, Valérie; Poirier, Paul; Pérusse, Louis; Tremblay, Angelo; Bouchard, Claude; Després, Jean-Pierre; Rhéaume, Caroline

    2011-12-01

    Individuals with insulin resistance and low cardiorespiratory fitness are frequently found to have an increased waist circumference and high exercise blood pressure. We tested the hypothesis that the relationships among insulin resistance, low cardiorespiratory fitness, and increased exercise blood pressure may be mediated by an elevated waist circumference. This study included 317 apparently healthy men and women (mean age: 34.8±12.8 years; mean body mass index: 26.1±5.2 kg/m(2)). Exercise blood pressure values were measured using a submaximal ergometer test evaluating physical working capacity. Plasma insulin and glucose levels were measured during a 3-hour oral glucose tolerance test. Multivariate regression analyses showed that waist circumference accounted for 32.8% (Pexercise systolic blood pressure in men and women, respectively. Participants were classified into tertiles according to either insulin response, measured during the oral glucose tolerance test, or fitness levels and then further subdivided into 2 subgroups using sex-specific waist circumference thresholds. Individuals with an increased waist circumference (≥94 cm and ≥80 cm for men and women, respectively) had higher exercise systolic blood pressure compared with individuals with low waist circumference, irrespective of their level of insulin resistance (10.6 versus 6.8, 12.2 versus 7.7, and 13.2 versus 8.7 mm Hg/metabolic equivalent, respectively, for the low, intermediate, and high tertiles; Pfitness levels (13.1 versus 8.2, 12.0 versus 7.9, and 10.6 versus 7.1 mm Hg/metabolic equivalent, respectively, for the low, intermediate, and high tertiles; Pexercise systolic blood pressure, regardless of their insulin sensitivity or level of cardiorespiratory fitness.

  19. High pressure effects on fruits and vegetables

    NARCIS (Netherlands)

    Timmermans, R.A.H.; Matser, A.M.

    2016-01-01

    The chapter provides an overview on different high pressure based treatments (high pressure pasteurization, blanching, pressure-assisted thermal processing, pressure-shift freezing and thawing) available for the preservation of fruits and vegetable products and extending their shelf life. Pressure t

  20. High pressure effects on fruits and vegetables

    NARCIS (Netherlands)

    Timmermans, R.A.H.; Matser, A.M.

    2016-01-01

    The chapter provides an overview on different high pressure based treatments (high pressure pasteurization, blanching, pressure-assisted thermal processing, pressure-shift freezing and thawing) available for the preservation of fruits and vegetable products and extending their shelf life. Pressure

  1. Questions and Answers about High Blood Pressure

    Science.gov (United States)

    ... checked out by a doctor. Am I at risk for high blood pressure? Anyone can develop high blood pressure. But there are several factors that increase your risk: Being overweight or obese Not ... if I have high blood pressure? High blood pressure is often called "the silent ...

  2. High Blood Pressure (Hypertension) (For Parents)

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old High Blood Pressure (Hypertension) KidsHealth > For Parents > High Blood Pressure (Hypertension) A ... posture, and medications. continue Long-Term Effects of High Blood Pressure When someone has high blood pressure, the heart ...

  3. High Blood Pressure (Hypertension) (For Parents)

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old High Blood Pressure (Hypertension) KidsHealth > For Parents > High Blood Pressure (Hypertension) ... posture, and medications. continue Long-Term Effects of High Blood Pressure When someone has high blood pressure, the heart ...

  4. Effects of intra-abdominal pressure on liver function assessed with the LiMON in critically ill patients.

    Science.gov (United States)

    Inal, Mehmet Turan; Memis, Dilek; Sezer, Y Atakan; Atalay, Meltem; Karakoc, Abdullah; Sut, Necdet

    2011-06-01

    Intra-abdominal pressure (IAP) and intra-abdominal hypertension (IAH) are associated with significant morbidity and mortality in critically ill patients. Our aim was to assess the effects of IAH on liver function using the noninvasive liver function monitoring system LiMON and to assess the prognostic value of IAP in critically ill patients. We conducted a retrospective analysis of critically ill patients who were treated in the intensive care unit (ICU). The IAP and indocyanine green plasma disappearance rate (ICG-PDR) measurements were made within 24 hours after admission to the ICU and repeated 12 hours later. Intra-abdominal pressure was measured via a Foley bladder catheter, and ICG elimination tests were conducted concurrently using the LiMON. We included 30 critically ill patients (17 women and 13 men aged 28-89 yr) in our analysis. Statistical analysis showed that the baseline IAP values were significantly higher among nonsurvivors than survivors (19.38 [standard deviation; SD 2.08] v. 13.07 [SD 0.99]). The twelfth-hour IAP values were higher than baseline measurements among nonsurvivors (21.50 [SD 1.96]) and lower than baseline measurements among survivors (11.71 [SD 1.54]); the difference between groups was significant (p LiMON is a good predictor of the effects of IAP on liver function and, thus, can be recommended for the evaluation of critically ill patients.

  5. Reproducibility of ultrasonography for assessing abdominal fat distribution in a population at high risk of diabetes

    DEFF Research Database (Denmark)

    Philipsen, A; Carstensen, Bendix; Sandbæk, Annelli

    2013-01-01

    Background:Visceral fat plays an important role in the development of metabolic disease independently of the effect of overall abdominal fat. Ultrasonography is an accessible method of accurately assessing abdominal fat distribution in epidemiological studies, but few details about...... the reproducibility of this method have been published.Objective:The aim of this study was to investigate the reproducibility of ultrasonography in the assessment of abdominal fat distribution in a population at high risk of type 2 diabetes.Design and Methods:Ultrasonography was used to estimate visceral...... and subcutaneous abdominal fat. Intra- and interobserver variation, short-term variation and variation between estimates in the fasting and non-fasting state were examined in three samples of 30, 33 and 23 participants from the ADDITION-PRO study. A variance components model was used to calculate intra...

  6. Intra-Abdominal Hypertension and Abdominal Compartment Syndrome after Abdominal Wall Reconstruction: Quaternary Syndromes?

    Science.gov (United States)

    Kirkpatrick, A W; Nickerson, D; Roberts, D J; Rosen, M J; McBeth, P B; Petro, C C; Berrevoet, Frederik; Sugrue, M; Xiao, Jimmy; Ball, C G

    2017-06-01

    Reconstruction with reconstitution of the container function of the abdominal compartment is increasingly being performed in patients with massive ventral hernia previously deemed inoperable. This situation places patients at great risk of severe intra-abdominal hypertension and abdominal compartment syndrome if organ failure ensues. Intra-abdominal hypertension and especially abdominal compartment syndrome may be devastating systemic complications with systematic and progressive organ failure and death. We thus reviewed the pathophysiology and reported clinical experiences with abnormalities of intra-abdominal pressure in the context of abdominal wall reconstruction. Bibliographic databases (1950-2015), websites, textbooks, and the bibliographies of previously recovered articles for reports or data relating to intra-abdominal pressure, intra-abdominal hypertension, and the abdominal compartment syndrome in relation to ventral, incisional, or abdominal hernia repair or abdominal wall reconstruction. Surgeons should thus consider and carefully measure intra-abdominal pressure and its resultant effects on respiratory parameters and function during abdominal wall reconstruction. The intra-abdominal pressure post-operatively will be a result of the new intra-peritoneal volume and the abdominal wall compliance. Strategies surgeons may utilize to ameliorate intra-abdominal pressure rise after abdominal wall reconstruction including temporizing paralysis of the musculature either temporarily or semi-permanently, pre-operative progressive pneumoperitoneum, permanently removing visceral contents, or surgically releasing the musculature to increase the abdominal container volume. In patients without complicating shock and inflammation, and in whom the abdominal wall anatomy has been so functionally adapted to maximize compliance, intra-abdominal hypertension may be transient and tolerable. Intra-abdominal hypertension/abdominal compartment syndrome in the specific setting of

  7. Pressure Drop in Cyclone Separator at High Pressure

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    For the design of pressurized circulating fluidized beds, experiments were conducted in a small cyclone with 120 mm in diameter and 300 mm in height at high pressures and at atmospheric temperatures. Influence of air leakage from the stand pipe into the cyclone was specially focused. A semi-empirical model was developed for the predic tion of the pressure drop of the cyclone separator at different operate pressures with the effect of air leakage and inlet solid loading. The operate pressure, air leakage and inlet solid loading act as significant roles in cyclone pressure drop. The pressure drop increases with the increasing of pressure and decreases with the increasing of the flow rate of air leakage from the standpipe and with the increasing of the inlet solid loading.

  8. Intraperitoneal and retroperitoneal carbon dioxide insufflation evoke different effects on caval vein pressure gradients in humans: evidence for the starling resistor concept of abdominal venous return.

    Science.gov (United States)

    Giebler, R M; Behrends, M; Steffens, T; Walz, M K; Peitgen, K; Peters, J

    2000-06-01

    The authors hypothesized that intraperitoneal and retroperitoneal carbon dioxide insufflation during surgical procedures evoke markedly different effects on the venous low-pressure system, induce different inferior caval vein pressure gradients at similar insufflation pressures, and may provide evidence for the Starling resistor concept of abdominal venous return. Intra- and extrathoracic caval vein pressures were measured using micromanometers during carbon dioxide insufflation at six cavity pressures (baseline and 10, 15, 20, and 24 mmHg and desufflation) in 20 anesthetized patients undergoing laparoscopic (supine, n = 8) or left (n = 6) or right (n = 6) retroperitoneoscopic (prone position) surgery. Intracavital, esophageal, and gastric pressures also were assessed. Data were analyzed for insufflation pressure-dependent and group effects by one-way and two-way analysis of variance for repeated measurements, respectively, followed by the Newman-Keuls post hoc test (P < 0.05). Intraperitoneal, unlike retroperitoneal, insufflation markedly increased, in an insufflation pressure-dependent fashion, the inferior-to-superior caval vein pressure gradient (P < 0.00001) at the level of the diaphragm. In contrast to what was observed with retroperitoneal insufflation, transmural intrathoracic caval vein pressure increased at 10 mmHg insufflation pressure, but the increase flattened with an insufflation pressure of more than 10 mmHg, and pressure decreased with an inflation pressure of 20 mmHg (P = 0.0397). These data are consistent with a zone 2 or 3 abdominal vascular condition during intraperitoneal and a zone 3 abdominal vascular condition during retroperitoneal insufflation. Intraperitoneal but not retroperitoneal carbon dioxide insufflation evokes a transition of the abdominal venous compartment from a zone 3 to a zone 2 condition, presumably impairing venous return, supporting the Starling resistor concept of abdominal venous return in humans.

  9. High-pressure microhydraulic actuator

    Science.gov (United States)

    Mosier, Bruce P [San Francisco, CA; Crocker, Robert W [Fremont, CA; Patel, Kamlesh D [Dublin, CA

    2008-06-10

    Electrokinetic ("EK") pumps convert electric to mechanical work when an electric field exerts a body force on ions in the Debye layer of a fluid in a packed bed, which then viscously drags the fluid. Porous silica and polymer monoliths (2.5-mm O.D., and 6-mm to 10-mm length) having a narrow pore size distribution have been developed that are capable of large pressure gradients (250-500 psi/mm) when large electric fields (1000-1500 V/cm) are applied. Flowrates up to 200 .mu.L/min and delivery pressures up to 1200 psi have been demonstrated. Forces up to 5 lb-force at 0.5 mm/s (12 mW) have been demonstrated with a battery-powered DC-DC converter. Hydraulic power of 17 mW (900 psi@ 180 uL/min) has been demonstrated with wall-powered high voltage supplies. The force and stroke delivered by an actuator utilizing an EK pump are shown to exceed the output of solenoids, stepper motors, and DC motors of similar size, despite the low thermodynamic efficiency.

  10. Application of a Silicone Sheet in Negative-Pressure Wound Therapy to Treat an Abdominal Wall Defect after Necrotizing Fasciitis

    Science.gov (United States)

    Shin, Jin Su

    2017-01-01

    Necrotizing fasciitis (NF) is an aggressive soft-tissue infection involving the deep fascia and is characterized by extensive deterioration of the surrounding tissue. Immediate diagnosis and intensive treatment, including debridement and systemic antibiotics, represent the most important factors influencing the survival of NF patients. In this report, we present a case of NF in the abdomen due to an infection caused by a perforated small bowel after abdominal liposuction. It was successfully treated using negative-pressure wound therapy, in which a silicone sheet functioned as a barrier between the sponge and internal organs to protect the small bowel. PMID:28194352

  11. Diagnosis of High Blood Pressure

    Medline Plus

    Full Text Available ... blood pressure test is easy and painless and can be done in a health care provider’s office ... severity of your blood pressure, he or she can order additional tests to determine if your blood ...

  12. Use of negative pressure wound therapy in the management of infected abdominal wounds containing mesh: an analysis of outcomes.

    Science.gov (United States)

    Baharestani, Mona Mylene; Gabriel, Allen

    2011-04-01

    The purpose of this study was to examine the clinical outcomes of negative pressure wound therapy (NPWT) using reticulated open-cell foam (ROCF) in the adjunctive management of abdominal wounds with exposed and known infected synthetic mesh. A non randomised, retrospective review of medical records for 21 consecutive patients with infected abdominal wounds treated with NPWT was conducted. All abdominal wounds contained exposed synthetic mesh [composite, polypropylene (PP), or knitted polyglactin 910 (PG) mesh]. Demographic and bacteriological data, wound history, pre-NPWT and comparative post-NPWT, operative procedures and complications, hospital length of stay (LOS) and wound healing outcomes were all analysed. Primary endpoints measured were (1) hospital LOS prior to initiation of NPWT, (2) total time on NPWT, (3) hospital LOS from NPWT initiation to discharge and (4) wound closure status at discharge. A total of 21 patients with abdominal wounds with exposed, infected mesh were treated with NPWT. Aetiology of the wounds was ventral hernia repair (n = 11) and acute abdominal wall defect (n = 10). Prior to NPWT initiation, the mean hospital LOS for the composite, PP and PG meshes were 76 days (range: 21-171 days), 51 days (range: 32-62 days) and 19 days (range: 12-39 days), respectively. The mean hospital LOS following initiation of NPWT for wounds with exposed composite, PP and PG mesh were 28, 31 and 32 days, respectively. Eighteen of the 21 wounds (86%) reached full closure after a mean time of 26 days of NPWT and a mean hospital LOS of 30 days postinitiation of NPWT. Three wounds, all with composite mesh left in situ, did not reach full closure, although all exhibited decreased wound dimensions, granulating beds and decreased surface area exposure of mesh. During NPWT/ROCF, one hypoalbuminemic patient with exposed PP mesh developed an enterocutaneous fistula over a prior enterotomy site. This patient subsequently underwent total mesh extraction, takedown of

  13. Managing Stress to Control High Blood Pressure

    Science.gov (United States)

    ... Aneurysm More Managing Stress to Control High Blood Pressure Updated:Jan 10,2017 The importance of stress ... content was last reviewed October 2016. High Blood Pressure • Home • Get the Facts About HBP • Know Your ...

  14. Avoid the Consequences of High Blood Pressure

    Science.gov (United States)

    ... Thromboembolism Aortic Aneurysm More Avoid the Consequences of High Blood Pressure Infographic Updated:Oct 31,2016 View a downloadable version of this infographic High Blood Pressure • Home • Get the Facts About HBP • Know Your ...

  15. High Blood Pressure: Keep the Beat Recipes

    Science.gov (United States)

    ... of this page please turn Javascript on. Feature: High Blood Pressure Keep the Beat Recipes Past Issues / Fall 2011 ... 65 million American adults—one in three—with high blood pressure, you have probably heard the advice, "watch your ...

  16. High blood pressure and eye disease

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000999.htm High blood pressure and eye disease To use the sharing features on this page, please enable JavaScript. High blood pressure can damage blood vessels in the retina . The ...

  17. Risk Factors for High Blood Pressure

    Science.gov (United States)

    ... Share this page from the NHLBI on Twitter. Risk Factors for High Blood Pressure Anyone can develop high blood pressure; however, age, ... Lifestyle Habits Unhealthy lifestyle habits can raise your risk for high blood pressure, and they include: Eating too much sodium or ...

  18. Effect of acute, slightly increased intra-abdominal pressure on intestinal permeability and oxidative stress in a rat model.

    Directory of Open Access Journals (Sweden)

    Yuxin Leng

    Full Text Available INTRODUCTION: Intra-abdominal hypertension (IAH is known as a common, serious complication in critically ill patients. Bacterial translocation and permeability changes are considered the pathophysiological bases for IAH-induced enterogenic endotoxemia and subsequent multiorgan failure. Nevertheless, the effects of slightly elevated intra-abdominal pressures (IAPs on the intestinal mucosa and the associated mechanisms remain unclear. METHODS: To investigate the acute effects of different nitrogen pneumoperitoneum grades on colonic mucosa, male Sprague-Dawley rats were assigned to six groups with different IAPs (0 [control], 4, 8, 12, 16, and 20 mmHg, n = 6/group. During 90 min of exposure, we dynamically monitored the heart rate and noninvasive hemodynamic parameters. After gradual decompression, arterial blood gas analyses were conducted. Thereafter, structural injuries to the colonic mucosa were identified using light microscopy. Colon permeability was determined using the expression of tight junction proteins, combined with fluorescein isothiocyanate dextran (FD-4 absorption. The pro-oxidant-antioxidant balance was determined based on the levels of malondialdehyde (MDA and antioxidant enzymes. RESULTS: IAH significantly affected the histological scores of the colonic mucosa, tight junction protein expression, mucosal permeability, and pro-oxidant-antioxidant balance. Interestingly, elevations of IAP that were lower than the threshold for IAH also showed a similar, undesirable effect. In the 8 mmHg group, mild hyponatremia, hypocalcemia, and hypoxemia occurred, accompanied by reduced blood and abdominal perfusion pressures. Mild microscopic inflammatory infiltration and increased MDA levels were also detected. Moreover, an 8-mm Hg IAP markedly inhibited the expression of tight junction proteins, although no significant differences in FD-4 permeability were observed between the 0- and 8-mmHg groups. CONCLUSIONS: Acute exposure to slightly

  19. Meteorology in ruptured abdominal aortic aneurysm: an institutional study and a meta-analysis of published studies reporting atmospheric pressure.

    Science.gov (United States)

    Takagi, H; Watanabe, T; Mizuno, Y; Kawai, N; Umemoto, T

    2014-12-01

    The aim of this paper was to determine whether weather factors including atmospheric pressure are associated with the occurrence of ruptured abdominal aortic aneurysm (RAAA). We investigated our institutional experiences of RAAA in more than 150 patients during 8 years. Further, we performed a meta-analysis of published studies reporting the influence of atmospheric pressure on RAAA. We retrospectively evaluated 152 patients who underwent surgery for RAAA (including ruptured iliac arterial aneurysm) at our institute between 1 January 2006 and 31 December 2013. Daily regional meteorological data (in the nearest weather station located 3.5 km from the hospital) were obtained online from Japan Meteorological Agency. To identify comparative studies of mean atmospheric pressure on the day with RAAA versus that on the day without RAAA, MEDLINE and EMBASE were searched through January 2014 using Web-based search engines (PubMed and OVID). Mean sea level atmospheric pressure, delta mean atmospheric pressure (difference between mean sea level atmospheric pressure on the day and that on the previous day), and sunshine duration on the day with RAAA were significantly lower than those on the day without RAAA: 1012.43±7.44 versus 1013.71±6.49 hPa, P=0.039, -1.18±5.15 versus 0.05±5.62 hPa, P=0.005; and 4.76±3.76 versus 5.47±3.88 h, P=0.026; respectively. A pooled analysis of 8 studies (including our institutional study) demonstrated that mean atmospheric pressure on the day with RAAA was significantly lower than that on the day without RAAA: standardized mean difference, -0.09; 95% confidence interval, -0.14 to -0.04; P=0.0009. Atmospheric pressure on the day with RAAA appears lower than that on the day without RAAA. Atmospheric pressure may be associated with the occurrence of RAAA.

  20. Effects of high-frequency current therapy on abdominal obesity in young women: a randomized controlled trial

    OpenAIRE

    Kim, Jin-Seop; Oh, Duck-won

    2015-01-01

    [Purpose] The aim of this study was to determine the effects of high-frequency current therapy on the abdominal obesity levels of young women. [Subjects] Twenty-two women with abdominal obesity were randomly allocated to either an experimental group (n 1 = 10) or a control group (n 2 = 12). [Methods] The experimental group subjects received high-frequency current therapy for the abdominal region 3 times per week for 6 weeks (a total of 18 sessions). Outcome measures were waist circumference, ...

  1. High-Pressure Lightweight Thrusters

    Science.gov (United States)

    Holmes, Richard; McKechnie, Timothy; Shchetkovskiy, Anatoliy; Smirnov, Alexander

    2013-01-01

    Returning samples of Martian soil and rock to Earth is of great interest to scientists. There were numerous studies to evaluate Mars Sample Return (MSR) mission architectures, technology needs, development plans, and requirements. The largest propulsion risk element of the MSR mission is the Mars Ascent Vehicle (MAV). Along with the baseline solid-propellant vehicle, liquid propellants have been considered. Similar requirements apply to other lander ascent engines and reaction control systems. The performance of current state-ofthe- art liquid propellant engines can be significantly improved by increasing both combustion temperature and pressure. Pump-fed propulsion is suggested for a single-stage bipropellant MAV. Achieving a 90-percent stage propellant fraction is thought to be possible on a 100-kg scale, including sufficient thrust for lifting off Mars. To increase the performance of storable bipropellant rocket engines, a high-pressure, lightweight combustion chamber was designed. Iridium liner electrodeposition was investigated on complex-shaped thrust chamber mandrels. Dense, uniform iridium liners were produced on chamber and cylindrical mandrels. Carbon/carbon composite (C/C) structures were braided over iridium-lined mandrels and densified by chemical vapor infiltration. Niobium deposition was evaluated for forming a metallic attachment flange on the carbon/ carbon structure. The new thrust chamber was designed to exceed state-of-the-art performance, and was manufactured with an 83-percent weight savings. High-performance C/Cs possess a unique set of properties that make them desirable materials for high-temperature structures used in rocket propulsion components, hypersonic vehicles, and aircraft brakes. In particular, more attention is focused on 3D braided C/Cs due to their mesh-work structure. Research on the properties of C/Cs has shown that the strength of composites is strongly affected by the fiber-matrix interfacial bonding, and that weakening

  2. How Is High Blood Pressure Treated?

    Science.gov (United States)

    ... or focusing on something calm or peaceful Performing yoga or tai chi Meditating Medicines Blood pressure medicines work in different ways to stop or slow some of the body’s functions that cause high blood pressure. Medicines to lower ...

  3. High blood pressure in women.

    Science.gov (United States)

    Calhoun, D A; Oparil, S

    1997-01-01

    There is a sexual dimorphism in blood pressure of humans and experimental animals: males tend to have higher blood pressure than females with functional ovaries, while ovariectomy or menopause tends to abolish the sexual dimorphism and cause females to develop a "male" pattern of blood pressure. Hypertensive male laboratory animals tend to have NaCl-sensitive blood pressure, while females are NaCl resistant unless their ovaries are removed, in which case NaCl sensitivity appears. The hormonal basis of NaCl sensitivity of blood pressure and of the sexual dimorphism of hypertension remains to be defined. Synthetic estrogens and progestins, as found in oral contraceptives, tend to elevate blood pressure, while naturally occurring estrogens lower it, or have no effect. Hypertension increases cardiovascular risk in women, as well as men, although the benefits of antihypertensive treatment have been more difficult to demonstrate in women. In the population of the United States, women are more aware of their hypertension, more likely to be treated medically, and more likely to have their blood pressure controlled.

  4. HIGH BLOOD PRESSURE: DOES THIS CONCERN ME?

    CERN Multimedia

    2007-01-01

    To find out, the Medical Service's nurses are organising A HIGH BLOOD PRESSURE SCREENING AND PREVENTION CAMPAIGN from Monday, 26th to Thursday, 29th March 2007 at the Infirmary - Building 57 - ground floor A blood pressure test, advice, information and, if necessary, referral for specialist medical treatment will be offered to any person working on the CERN site. High blood pressure is a stealth threat to health. So come and get your blood pressure checked.

  5. HIGH BLOOD PRESSURE: DOES THIS CONCERN ME?

    CERN Multimedia

    2007-01-01

    To find out, the Medical Service's nurses are organising A HIGH BLOOD PRESSURE SCREENING AND PREVENTION CAMPAIGN from Monday, 26th to Thursday, 29th March 2007 at the Infirmary - Building 57 - ground floor A blood pressure test, advice, information and, if necessary, referral for specialist medical treatment will be offered to any person working on the CERN site. High blood pressure is a silent threat to health. So come and get your blood pressure checked.

  6. Diagnosis of High Blood Pressure

    Medline Plus

    Full Text Available ... Events Spokespeople Email Alerts E-Newsletters About NHLBI Organization NHLBI Director Budget, Planning, & Legislative Advisory Committees Jobs ... track blood pressure readings over a period of time, the health care provider may ask you to ...

  7. Application of High Pressure in Food Processing

    OpenAIRE

    Herceg, Z; Režek Jambrak, A; Lelas, V.; Krešić, G.

    2011-01-01

    In high pressure processing, foods are subjected to pressures generally in the range of 100 – 800 (1200) MPa. The processing temperature during pressure treatments can be adjusted from below 0 °C to above 100 °C, with exposure times ranging from a few seconds to 20 minutes and even longer, depending on process conditions. The effects of high pressure are system volume reduction and acceleration of reactions that lead to volume reduction. The main areas of interest regarding high-pressure proc...

  8. 分娩前后腹腔内压的测定%Determination of intra-abdominal pressure before and after delivery

    Institute of Scientific and Technical Information of China (English)

    王艳; 梁丽霞; 邓燕红

    2015-01-01

    ObjectiveTo compare the changes of intra-abdominal pressure (IAP) and hemodynamic differences before and after delivery in the normal pregnant women.Methods24 pregnant women,who were going to deliver in the Third Affiliated Hospital of Guangzhou Medical College from November 2011 to March 2012,were divided into a single pregnancy group (20 cases) and a twin pregnancy group (4 cases) according to the pregnant categories.Then the changes of intra-abdominal pressure before and after delivery were monitored by intravesical pressure measurement,in additional,the changes of blood pressure,abdominal perfusion pressure and heart rate were observed.Results(1) In the single pregnancy group,the systolic blood pressure and diastolic blood pressure of the pregnant women after delivery were (118.05±10.12)mm Hg and (70.95±7.65)mm Hg respectively,with no significant differences from those before delivery (P>0.05);While maternal heart rate after the delivery was(83.76±11.31)/min,which was significantly decreased compared with that before delivery of (95.29±14.11)/min,and abdominal perfusion pressure increased significantly than that before delivery,and the differences were significant (P<0.01).(2)The IAP range of women with singleton pregnancy was from 14.28 to 48.96mm Hg with an average of (35.13±8.81)mm Hg before delivery, so the incidence of intra-abdominal hypertension (IAP high 12mmHg) was 100%;While IAP range after delivery was from 8.84 to 25.84 mmHg with an average of(16.16±4.61)mm Hg,so the incidence of intra-abdominal hypertension was 85.7% (18/21),there was a significant difference before and after childbirth (P<0.01).(3)The IAP of women with twin pregnancy before delivery was (38.25±10.18)mm Hg,which was in the range of intra-abdominal hypertension;While that after delivery was (22.61±10.98)mm Hg,only 75% (3/4)of those were diagnosed intra-abdominal hypertension. In short,IAP decreased significantly after delivery (P<0.01). Conclusion The IAP of normal women

  9. Positive end expiratory pressure titrated by transpulmonary pressure improved oxygenation and respiratory mechanics in acute respiratory distress syndrome patients with intra-abdominal hypertension

    Institute of Scientific and Technical Information of China (English)

    YANG Yi; LI Yang; LIU Song-qiao; LIU Ling; HUANG Ying-zi; GUO Feng-mei; QIU Hai-bo

    2013-01-01

    Background Intra-abdominal hypertension (IAH) is common in acute respiratory distress syndrome (ARDS) patients and when resulting in decrease of chest wall compliance will weaken the effect of positive end expiratory pressure (PEEP).We investigated the effect of PEEP titrated by transpulmonary pressure (Ptp) on oxygenation and respiratory mechanics in ARDS patients with IAH compared with PEEP titrated by ARDSnet protocol.Methods ARDS patients admitted to the intensive care unit (ICU) of the Zhongda Hospital were enrolled.Patients were ventilated with volume control mode with tidal volume of 6 ml/kg under two different PEEP levels titrated by Ptp method and ARDSnet protocol.Respiratory mechanics,gas exchange and haemodynamics were measured after 30 minutes of ventilation in each round.IAH was defined as intra-abdominal pressure of 12 mmHg or more.Results Seven ARDS patients with IAH and 8 ARDS patients without IAH were enrolled.PEEP titrated by Ptp were significant higher than PEEP titrated by ARDSnet protocol in both ARDS patients with IAH ((17.3±2.6) cmH2O vs.(6.3±1.6)cmH2O and without IAH ((9.5±2.1) cmH2O vs.(7.8±1.9) cmH2O).Arterial pressure of O2/fraction of inspired oxygen (PaO2/FiO2)was much higher under PEEP titrated by Ptp when compared with PEEP titrated by ARDSnet protocol in ARDS patients with IAH ((27.2±4.0) cmHg vs.(20.9± 5.0) cmHg.But no significant difference of PaO2/FiO2 between the two methods was found in ARDS patients without IAH.In ARDS patients with IAH,static compliance of lung and respiratory system were higher under PEEP titrated by Ptp than by ARDSnet protocol.In ARDS patients with IAH,central venous pressure (CVP) was higher during PEEP titrated by Ptp than byARDSnet protocol.Conclusion Positive end expiratory pressure titrated by transpulmonary pressure was higher than PEEP titrated by ARDSnet protocol and improved oxygenation and respiratory mechanics in ARDS patients with IAH.

  10. Metallicity of boron carbides at high pressure

    Science.gov (United States)

    Dekura, Haruhiko; Shirai, Koun; Yanase, Akira

    2010-03-01

    Electronic structure of semiconducting boron carbide at high pressure has been theoretically investigated, because of interests in the positive pressure dependence of resistivity, in the gap closure, and in the phase transition. The most simplest form B12(CCC) is assumed. Under assumptions of hydrostatic pressure and neglecting finite-temperature effects, boron carbide is quite stable at high pressure. The crystal of boron carbide is stable at least until a pressure higher than previous experiments showed. The gap closure occurs only after p=600 GPa on the assumption of the original crystal symmetry. In the low pressure regime, the pressure dependence of the energy gap almost diminishes, which is an exceptional case for semiconductors, which could be one of reasons for the positive pressure dependence of resistivity. A monotonous increase in the apex angle of rhombohedron suggests that the covalent bond continues to increase. The C chain inserted in the main diagonal of rhombohedral structure is the chief reason of this stability.

  11. Effects of a Belt on Intra-Abdominal Pressure during Weight Lifting.

    Science.gov (United States)

    1988-03-01

    pressure was measured using a Millar model SPC 350 Mikro -Tip catheter pressure transducer (Millar Instruments, Houston, TX) inserted nasally. The...316.16 # .33*.16 # start of pressure plateau .20*.06 # .10*.13 # a.peak pro -plateau rate of force increase -.1O’.14 -.1O*A.16 peak pre-plateau rate of...off (Nosec) 354*185 432*198 impulse: lift-off to end (NOsOc) 4904*1299 4948*1269 peak pro -plateau rate of force incr. (N/sec) 71382*15258 69482*19156

  12. Diagnosis of High Blood Pressure

    Medline Plus

    Full Text Available ... Technology Transfer Clinical Trials What Are Clinical Trials? Children & Clinical Studies NHLBI Trials Clinical Trial Websites News & ... are consistently higher than 120/80 mmHg. Your child’s blood pressure numbers are outside average numbers for ...

  13. Diagnosis of High Blood Pressure

    Medline Plus

    Full Text Available ... Related Topics Atherosclerosis DASH Eating Plan Overweight and Obesity Smoking and Your Heart Stroke Send a link ... are consistently higher than 120/80 mmHg. Your child’s blood pressure numbers are outside average numbers for ...

  14. Atmospheric Pressure Changes Are Associated with Type A Acute Aortic Dissections and Spontaneous Abdominal Aortic Aneurysm Rupture in Tuzla Canton

    Science.gov (United States)

    Krdzalic, Alisa; Rifatbegovic, Zijah; Krdzalic, Goran; Jahic, Elmir; Adam, Visnja Nesek; Golic, Darko

    2014-01-01

    Aim: The aim of this study was to investigate a relationship between seasonal variation and incidence of type A acute aortic dissection (AAD) and spontaneous abdominal aneurysm rupture (rAAA) in Canton Tuzla, Bosnia and Herzegovina. Patients and methods: A total of 81 cases, 41 AAD and 40 of ruptured AAA were identified from one center over a 6-year, from 2008 till 2013. In 2012 were admitted (45.6% or 36 patients). Results: Seasonal analysis showed that 19(23.4%) patients were admitted in spring, 15(18.5) in summer, 26(32%) in autumn and 21(25.9) in winter. The most frequent period was autumn/winter with 47 or 58% patients. A causal link between atmospheric pressure (AP) and incidence of rAAA and AAD on seasonal and monthly basis was found. PMID:25568523

  15. Management of severe lower abdominal or inguinal pain in high-performance athletes. PAIN (Performing Athletes with Abdominal or Inguinal Neuromuscular Pain Study Group).

    Science.gov (United States)

    Meyers, W C; Foley, D P; Garrett, W E; Lohnes, J H; Mandlebaum, B R

    2000-01-01

    The purpose of this study was to gain insight into the pathophysiologic processes of severe lower-abdominal or inguinal pain in high-performance athletes. We evaluated 276 patients; 175 underwent pelvic floor repairs. Of the 157 athletes who had not undergone previous surgery, 124 (79%) participated at a professional or other highly competitive level, and 138 patients (88%) had adductor pain that accompanied the lower-abdominal or inguinal pain. More patients underwent related adductor releases during the later operative period in the series. Evaluation revealed 38 other abnormalities, including severe hip problems and malignancies. There were 152 athletes (97%) who returned to previous levels of performance. The syndrome was uncommon in women and the results were less predictable in nonathletes. A distinct syndrome of lower-abdominal/adductor pain in male athletes appears correctable by a procedure designed to strengthen the anterior pelvic floor. The location and pattern of pain and the operative success suggest the cause to be a combination of abdominal hyperextension and thigh hyperabduction, with the pivot point being the pubic symphysis. Diagnosis of "athletic pubalgia" and surgery should be limited to a select group of high-performance athletes. The consideration of other causes of groin pain in the patient is critical.

  16. High pressure processing for food safety.

    Science.gov (United States)

    Fonberg-Broczek, Monika; Windyga, B; Szczawiński, J; Szczawińska, M; Pietrzak, D; Prestamo, G

    2005-01-01

    Food preservation using high pressure is a promising technique in food industry as it offers numerous opportunities for developing new foods with extended shelf-life, high nutritional value and excellent organoleptic characteristics. High pressure is an alternative to thermal processing. The resistance of microorganisms to pressure varies considerably depending on the pressure range applied, temperature and treatment duration, and type of microorganism. Generally, Gram-positive bacteria are more resistant to pressure than Gram-negative bacteria, moulds and yeasts; the most resistant are bacterial spores. The nature of the food is also important, as it may contain substances which protect the microorganism from high pressure. This article presents results of our studies involving the effect of high pressure on survival of some pathogenic bacteria -- Listeria monocytogenes, Aeromonas hydrophila and Enterococcus hirae -- in artificially contaminated cooked ham, ripening hard cheese and fruit juices. The results indicate that in samples of investigated foods the number of these microorganisms decreased proportionally to the pressure used and the duration of treatment, and the effect of these two factors was statistically significant (level of probability, P high pressure treatment than L. monocytogenes and A. hydrophila. Mathematical methods were applied, for accurate prediction of the effects of high pressure on microorganisms. The usefulness of high pressure treatment for inactivation of microorganisms and shelf-life extention of meat products was also evaluated. The results obtained show that high pressure treatment extends the shelf-life of cooked pork ham and raw smoked pork loin up to 8 weeks, ensuring good micro-biological and sensory quality of the products.

  17. CHRONOBIOLOGY OF HIGH BLOOD PRESSURE

    Science.gov (United States)

    Cornélissen, G.; Halberg, F.; Bakken, E. E.; Wang, Z.; Tarquini, R.; Perfetto, F.; Laffi, G.; Maggioni, C.; Kumagai, Y.; Homolka, P.; Havelková, A.; Dušek, J.; Svačinová, H.; Siegelová, J.; Fišer, B.

    2008-01-01

    BIOCOS, the project aimed at studying BIOlogical systems in their COSmos, has obtained a great deal of expertise in the fields of blood pressure (BP) and heart rate (HR) monitoring and of marker rhythmometry for the purposes of screening, diagnosis, treatment, and prognosis. Prolonging the monitoring reduces the uncertainty in the estimation of circadian parameters; the current recommendation of BIOCOS requires monitoring for at least 7 days. The BIOCOS approach consists of a parametric and a non-parametric analysis of the data, in which the results from the individual subject are being compared with gender- and age-specified reference values in health. Chronobiological designs can offer important new information regarding the optimization of treatment by timing its administration as a function of circadian and other rhythms. New technological developments are needed to close the loop between the monitoring of blood pressure and the administration of antihypertensive drugs. PMID:19122770

  18. Comparing intra-abdominal pressures in different body positions via a urinary catheter and nasogastric tube: a pilot study.

    Science.gov (United States)

    Rooban, Nirooshan; Regli, Adrian; Davis, Wendy A; De Keulenaer, Bart L

    2012-07-05

    Intra-abdominal pressure (IAP) is most commonly measured via the bladder with the patient in the supine position. In the ICU, patients are nursed with the head of the bed elevated at 30° (HOB30) to reduce the risk of ventilator-associated pneumonia. This study investigated whether gastric pressure at HOB30 can be used as a surrogate measure of IAP via the bladder in the supine position. A prospective observational study was conducted in a single-centre intensive care unit. A total of 20 patients were included. IAP was recorded simultaneously via the bladder catheter (bladder pressure, IBP) and via nasogastric tube (gastric pressures, IGP) in the supine and HOB30 position. Each patient had three sets of IAP measurements performed at least 4 h apart. In the supine position, mean IBP was 12.3 ± 4.5 mmHg compared to IGP of 11.8 ± 4.7 mmHg. The bias between the two groups was 0.5 and precision of 3.7 (LA, -6.8 to 7.5 mmHg). At 30 degrees, mean IBP was 15.8 ± 4.9 mmHg compared to IGP of 13.1 ± 6.1 mmHg. The bias between both groups was 2.7 with a precision of 5.5 (LA, -8.0 to 13.5). Comparing IBP in the supine position with IGP at 30° showed a bias of -0.8 and precision of 5.6 (LA, -10.1 to 11.6 mmHg). IAP measured via a nasogastric tube was less influenced by changing the body position from supine to HOB30 than was bladder pressure.

  19. Relación entre la presión intrabdominal en diálisis peritoneal con las hernias y fugas The link between intra-abdominal pressure in peritoneal dialysis and hernias and fugues

    Directory of Open Access Journals (Sweden)

    Concepción Blasco Cabañas

    2012-06-01

    ±253 ml/m². Un 23.5 % tenían una presión intrabdominal mayor a 20 cm. de H2O. En sedestación la media fue de 28±5.5 cm. de H2O y en bipedestación de 43.7±5.3 cm. de H2O. Los enfermos con presión intrabdominal > 20 cm. H2O tenían más porcentaje de hernias (50% vs 12 % y fugas pericatéter (37 % vs. 12 %. Como principales conclusiones, podemos destacar que los niveles de presión intrabdominal de nuestros pacientes son algo más elevados que en otras series. A mayor edad, mayor comorbilidad y mayor índice de masa corporal, la presión intrabdominal es más elevada. Los enfermos con presión intrabdominal elevada presentaron más episodios de hernias y fugas.Normal intra-abdominal pressure is equal to atmospheric pressure (zero. In peritoneal dialysis the introduction of intra-peritoneal liquid increases intra-abdominal pressure. In various studies it is recommended that this does not exceed 16-20cm H2O. In addition to possible abdominal discomfort, high intra-abdominal pressure can be linked to problems with the abdominal wall, such as hernias and fugues, and have implications for peritoneal transport and ultrafiltration deficit. The aims of this study were the following: to find out the intra-abdominal pressure levels in the prevalent type of patients in peritoneal dialysis, to assess the factors influencing the values for this pressure and to study the relationship between intra-abdominal pressure and the development of hernias and fugues, retrospectively. A transversal, observational and retrospective study was conducted to measure intra-abdominal pressure in the prevalent, stable patients who had been on peritoneal dialysis for more than three months. Intra-abdominal pressure was measured using the method described by Durand: patient in a supine position, with diurnal peritoneal volume. The final intra-abdominal pressure is the average of the measurements taken during inspiration and expiration, is expressed in cm H2O and the volume drained is

  20. High Temperature and Pressure Alkaline Electrolysis

    DEFF Research Database (Denmark)

    Allebrod, Frank

    and oxygen with a new type of alkaline electrolysis cell at high temperatures and pressures. To perform measurements under high pressure and at elevated temperatures it was necessary to build a measurement system around an autoclave which could stand high temperatures up to 250 °C and pressures up to 200 bar...... as well as extremely caustic environments. Based on a literature study to identify resistant materials for these conditions, Inconel 600 was selected among the metals which are available for autoclave construction. An initial single atmosphere high temperature and pressure measurement setup was build...... comprising this autoclave. A second high temperature and pressure measurement setup was build based on experiences from the first setup in order to perform automatized measurements. The conductivity of aqueous KOH at elevated temperatures and high concentrations was investigated using the van der Pauw method...

  1. [Systolic pressure, abdominal obesity and body fat, metabolic syndrome predictors in Spanish preschoolers].

    Science.gov (United States)

    Gutiérrez Hervás, Ana Isabel; Rizo Baeza, María Mercedes; Martínez Amorós, Natalia; Cortés Castell, Ernesto

    2015-05-01

    Se plantea como objetivo determinar la presencia de predictores de síndrome metabólico en niños de 2 a 7 años en relación a su estado nutricional. Método: Estudio descriptivo con análisis cuantitativo en 260 niños de 2-7 años (135 niñas y 125 niños), 66% del total censados. Se midieron parámetros antropométricos y tensión arterial y se calcularon IMC, grasa corporal según Hoffman e índice cintura-talla (ICT). Se realizaron subgrupos con Z-Score del IMC según edad y sexo (bajo peso, normopeso, sobrepeso y obesidad), según grasa corporal (normal y con exceso), ICT (normal y obesidad abdominal) y tensión sistólica (normotensos e hipertensos según edad y sexo). Se utilizó como variable principal la clasificación según Z-Score del IMC. Resultados: La prevalencia combinada de sobrepeso y obesidad fue del 27%, sin diferencias por sexo. El estado nutricional relacionó significativamente con tensión arterial, grasa corporal e índice cintura-talla. Mayor porcentaje de obesos con tensión arterial sistólica alta que de normonutridos (OR=4.1; IC95% 1.7-9.8; p.

  2. Pre-eclampsia renamed and reframed: Intra-abdominal hypertension in pregnancy.

    Science.gov (United States)

    Sawchuck, Diane J; Wittmann, Bernd K

    2014-11-01

    This hypothesis proposes pre-eclampsia is caused by intra-abdominal hypertension in pregnancy. Sustained or increasing intra-abdominal pressure ⩾12mmHg causes impaired venous return to the heart, systemic vascular resistance, ischemia reperfusion injury, intestinal permeability, translocation of lipopolysaccharide endotoxin to the liver, cytotoxic immune response, systemic inflammatory response, pressure transmission to thoracic and intra-cranial compartments, and multi-organ dysfunction. This hypothesis is predicated on Pascal's law, evidence founded in the intra-abdominal hypertension literature, and the adapted equation ΔIAP-P=ΔIAVF/Cab, where ΔIAP-P=change in intra-abdominal pressure in pregnancy, ΔIAVF=change in intra-abdominal vector force (volume and force direction) and Cab=abdominal compliance. Factors causing increased intra-abdominal pressure in pregnancy include: progressive uterine expansion, obstetrical factors that increase intra-uterine volume excessively or acutely, maternal anthropometric measurements that affect intra-abdominal pressure thresholds, maternal postures that increase abdominal force direction, abdominal compliance that is decreased, diminished with advancing gestation, or has reached maximum expansion, habitation at high altitude, and rapid drops in barometric pressure. We postulate that the threshold for lipopolysaccharide translocation depends on the magnitude of intra-abdominal pressure, the intestinal microbiome complex, and the degree of intestinal permeability. We advance that delivery cures pre-eclampsia through the mechanism of abdominal decompression.

  3. Application of High Pressure in Food Processing

    Directory of Open Access Journals (Sweden)

    Herceg, Z.

    2011-01-01

    Full Text Available In high pressure processing, foods are subjected to pressures generally in the range of 100 – 800 (1200 MPa. The processing temperature during pressure treatments can be adjusted from below 0 °C to above 100 °C, with exposure times ranging from a few seconds to 20 minutes and even longer, depending on process conditions. The effects of high pressure are system volume reduction and acceleration of reactions that lead to volume reduction. The main areas of interest regarding high-pressure processing of food include: inactivation of microorganisms, modification of biopolymers, quality retention (especially in terms of flavour and colour, and changes in product functionality. Food components responsible for the nutritive value and sensory properties of food remain unaffected by high pressure. Based on the theoretical background of high-pressure processing and taking into account its advantages and limitations, this paper aims to show its possible application in food processing. The paper gives an outline of the special equipment used in highpressure processing. Typical high pressure equipment in which pressure can be generated either by direct or indirect compression are presented together with three major types of high pressure food processing: the conventional (batch system, semicontinuous and continuous systems. In addition to looking at this technology’s ability to inactivate microorganisms at room temperature, which makes it the ultimate alternative to thermal treatments, this paper also explores its application in dairy, meat, fruit and vegetable processing. Here presented are the effects of high-pressure treatment in milk and dairy processing on the inactivation of microorganisms and the modification of milk protein, which has a major impact on rennet coagulation and curd formation properties of treated milk. The possible application of this treatment in controlling cheese manufacture, ripening and safety is discussed. The opportunities

  4. Laser techniques in high-pressure geophysics

    Science.gov (United States)

    Hemley, R. J.; Bell, P. M.; Mao, H. K.

    1987-01-01

    Laser techniques in conjunction with the diamond-anvil cell can be used to study high-pressure properties of materials important to a wide range of problems in earth and planetary science. Spontaneous Raman scattering of crystalline and amorphous solids at high pressure demonstrates that dramatic changes in structure and bonding occur on compression. High-pressure Brillouin scattering is sensitive to the pressure variations of single-crystal elastic moduli and acoustic velocities. Laser heating techniques with the diamond-anvil cell can be used to study phase transitions, including melting, under deep-earth conditions. Finally, laser-induced ruby fluorescence has been essential for the development of techniques for generating the maximum pressures now possible with the diamond-anvil cell, and currently provides a calibrated in situ measure of pressure well above 100 gigapascals.

  5. Laser techniques in high-pressure geophysics

    Science.gov (United States)

    Hemley, R. J.; Bell, P. M.; Mao, H. K.

    1987-01-01

    Laser techniques in conjunction with the diamond-anvil cell can be used to study high-pressure properties of materials important to a wide range of problems in earth and planetary science. Spontaneous Raman scattering of crystalline and amorphous solids at high pressure demonstrates that dramatic changes in structure and bonding occur on compression. High-pressure Brillouin scattering is sensitive to the pressure variations of single-crystal elastic moduli and acoustic velocities. Laser heating techniques with the diamond-anvil cell can be used to study phase transitions, including melting, under deep-earth conditions. Finally, laser-induced ruby fluorescence has been essential for the development of techniques for generating the maximum pressures now possible with the diamond-anvil cell, and currently provides a calibrated in situ measure of pressure well above 100 gigapascals.

  6. Design optimization of high pressure and high temperature piezoresistive pressure sensor for high sensitivity

    Science.gov (United States)

    Niu, Zhe; Zhao, Yulong; Tian, Bian

    2014-01-01

    This paper describes a design method for optimizing sensitivity of piezoresistive pressure sensor in high-pressure and high-temperature environment. In order to prove the method, a piezoresistive pressure sensor (HPTSS) is designed. With the purpose of increasing sensitivity and to improve the measurement range, the piezoresistive sensor adopts rectangular membrane and thick film structure. The configuration of piezoresistors is arranged according to the characteristic of the rectangular membrane. The structure and configuration of the sensor chip are analyzed theoretically and simulated by the finite element method. This design enables the sensor chip to operate in high pressure condition (such as 150 MPa) with a high sensitivity and accuracy. The silicon on insulator wafer is selected to guarantee the thermo stability of the sensor chip. In order to optimize the fabrication and improve the yield of production, an electric conduction step is devised. Series of experiments demonstrates a favorable linearity of 0.13% and a high accuracy of 0.48%. And the sensitivity of HTPSS is about six times as high as a conventional square-membrane sensor chip in the experiment. Compared with the square-membrane pressure sensor and current production, the strength of HPTTS lies in sensitivity and measurement. The performance of the HPTSS indicates that it could be an ideal candidate for high-pressure and high-temperature sensing in real application.

  7. Design optimization of high pressure and high temperature piezoresistive pressure sensor for high sensitivity.

    Science.gov (United States)

    Niu, Zhe; Zhao, Yulong; Tian, Bian

    2014-01-01

    This paper describes a design method for optimizing sensitivity of piezoresistive pressure sensor in high-pressure and high-temperature environment. In order to prove the method, a piezoresistive pressure sensor (HPTSS) is designed. With the purpose of increasing sensitivity and to improve the measurement range, the piezoresistive sensor adopts rectangular membrane and thick film structure. The configuration of piezoresistors is arranged according to the characteristic of the rectangular membrane. The structure and configuration of the sensor chip are analyzed theoretically and simulated by the finite element method. This design enables the sensor chip to operate in high pressure condition (such as 150 MPa) with a high sensitivity and accuracy. The silicon on insulator wafer is selected to guarantee the thermo stability of the sensor chip. In order to optimize the fabrication and improve the yield of production, an electric conduction step is devised. Series of experiments demonstrates a favorable linearity of 0.13% and a high accuracy of 0.48%. And the sensitivity of HTPSS is about six times as high as a conventional square-membrane sensor chip in the experiment. Compared with the square-membrane pressure sensor and current production, the strength of HPTTS lies in sensitivity and measurement. The performance of the HPTSS indicates that it could be an ideal candidate for high-pressure and high-temperature sensing in real application.

  8. Increased long-term mortality after a high perioperative inspiratory oxygen fraction during abdominal surgery

    DEFF Research Database (Denmark)

    Meyhoff, Christian Sylvest; Jorgensen, Lars N; Wetterslev, Jørn;

    2012-01-01

    A high perioperative inspiratory oxygen fraction (80%) has been recommended to prevent postoperative wound infections. However, the most recent and one of the largest trials, the PROXI trial, found no reduction in surgical site infection, and 30-day mortality was higher in patients given 80% oxygen....... In this follow-up study of the PROXI trial we assessed the association between long-term mortality and perioperative oxygen fraction in patients undergoing abdominal surgery....

  9. Techniques in high pressure neutron scattering

    CERN Document Server

    Klotz, Stefan

    2013-01-01

    Drawing on the author's practical work from the last 20 years, Techniques in High Pressure Neutron Scattering is one of the first books to gather recent methods that allow neutron scattering well beyond 10 GPa. The author shows how neutron scattering has to be adapted to the pressure range and type of measurement.Suitable for both newcomers and experienced high pressure scientists and engineers, the book describes various solutions spanning two to three orders of magnitude in pressure that have emerged in the past three decades. Many engineering concepts are illustrated through examples of rea

  10. Influence of lumbar spine rhythms and intra-abdominal pressure on spinal loads and trunk muscle forces during upper body inclination.

    Science.gov (United States)

    Arshad, Rizwan; Zander, Thomas; Dreischarf, Marcel; Schmidt, Hendrik

    2016-04-01

    Improved knowledge on spinal loads and trunk muscle forces may clarify the mechanical causes of various spinal diseases and has the potential to improve the current treatment options. Using an inverse dynamic musculoskeletal model, this sensitivity analysis was aimed to investigate the influence of lumbar spine rhythms and intra-abdominal pressure on the compressive and shear forces in L4-L5 disc and the trunk muscle forces during upper body inclination. Based on in vivo data, three different spine rhythms (SRs) were used along with alternative settings (with/without) of intra-abdominal pressure (IAP). Compressive and shear forces in L4-L5 disc as well as trunk muscle forces were predicted by inverse static simulations from standing upright to 55° of intermediate trunk inclination. Alternate model settings of intra-abdominal pressure and different spine rhythms resulted in significant variation of compression (763 N) and shear forces (195 N) in the L4-L5 disc and in global (454 N) and local (156 N) trunk muscle forces at maximum flexed position. During upper body inclination, the compression forces at L4-L5 disc were mostly released by IAP and increased for larger intervertebral rotation in a lumbar spine rhythm. This study demonstrated that with various possible assumptions of lumbar spine rhythm and intra-abdominal pressure, variation in predicted loads and muscles forces increase with larger flexion. It is therefore, essential to adapt these model parameters for accurate prediction of spinal loads and trunk muscle forces.

  11. High-pressure minerals in shocked meteorites

    Science.gov (United States)

    Tomioka, Naotaka; Miyahara, Masaaki

    2017-09-01

    Heavily shocked meteorites contain various types of high-pressure polymorphs of major minerals (olivine, pyroxene, feldspar, and quartz) and accessory minerals (chromite and Ca phosphate). These high-pressure minerals are micron to submicron sized and occur within and in the vicinity of shock-induced melt veins and melt pockets in chondrites and lunar, howardite-eucrite-diogenite (HED), and Martian meteorites. Their occurrence suggests two types of formation mechanisms (1) solid-state high-pressure transformation of the host-rock minerals into monomineralic polycrystalline aggregates, and (2) crystallization of chondritic or monomineralic melts under high pressure. Based on experimentally determined phase relations, their formation pressures are limited to the pressure range up to 25 GPa. Textural, crystallographic, and chemical characteristics of high-pressure minerals provide clues about the impact events of meteorite parent bodies, including their size and mutual collision velocities and about the mineralogy of deep planetary interiors. The aim of this article is to review and summarize the findings on natural high-pressure minerals in shocked meteorites that have been reported over the past 50 years.

  12. Validation of a novel method for measuring intra-abdominal pressure and gastric residual volume in critically ill patients.

    Science.gov (United States)

    Van Stappen, Johan; Pigozzi, Chiara; Tepaske, Robert; Van Regenmortel, Niels; De Laet, Inneke; Schoonheydt, Karen; Dits, Hilde; Severgnini, Paolo; Roberts, Derek J; Malbrain, Manu L N G

    2014-01-01

    Gastric residual volume (GRV) can be measured in a variety of ways in critically ill patients, most often, the nasogastric tube is disconnected and the GRV is aspirated via a 60 mL syringe. Bladder pressure (IBP) measurement is the gold standard for intra-abdominal pressure (IAP) estimation. This study will look at the validation of a novel method combining measurement of GRV and estimation of IAP via intra-gastric pressure (IGP). In total 135 paired IAP and 146 paired GRV measurements were performed in 37 mechanically ventilated ICU patients. The IAP was estimated via the bladder (i.e. IBP) using the FoleyManometer and via the stomach (i.e. IGP) with the new device. The GRV was measured with the new device (GRVprototype) and via the classic method (GRVclassic). The devices were provided by Holtech Medical (Charlottenlund, Denmark) and data were retrospectively analysed. The number of paired measurements in each patient was 4 ± 1. The mean IBP was 10.7 ± 4.1 and mean IGP was 11.6 ± 4.1 mm Hg. Correlation between the IBP and IGP was significant, however moderate (R2 = 0.51). Analysis according to Bland and Altman showed a bias and precision of 0.8 and 2.7 mm Hg respectively, however the limits of agreement (LA) were large and ranged from -4.5 to 6.1 mm Hg. Changes in IGP correlated well with changes in IBP. The median GRVprototype was 80 mL (0-1050) and equal to the median GRVclassic of 80 mL (0-1250). Correlation between the 2 methods was excellent (R2 = 0.89). Analysis according to Bland and Altman showed a bias and precision of -0.8 and 52.3 mL respectively and the LA ranged from -103 to 102 mL. Changes in GRVclassic correlated well with changes in GRVprototype. The results of this multicentre pilot study show that GRV can be measured with the new device. Furthermore this allows simultaneous screening for intra-abdominal hypertension with IAP estimation via IGP.

  13. Portable high precision pressure transducer system

    Science.gov (United States)

    Piper, T. C.; Morgan, J. P.; Marchant, N. J.; Bolton, S. M.

    A high precision pressure transducer system for checking the reliability of a second pressure transducer system used to monitor the level of a fluid confined in a holding tank is presented. Since the response of the pressure transducer is temperature sensitive, it is continually housed in a battery powered oven which is configured to provide a temperature stable environment at specified temperature for an extended period of time. Further, a high precision temperature stabilized oscillator and counter are coupled to a single board computer to accurately determine the pressure transducer oscillation frequency and convert it to an applied pressure. All of the components are powered by the batteries which during periods of availability of line power are charged by an on-board battery charger. The pressure readings outputs are transmitted to a line printer and a vacuum fluorescent display.

  14. Effect of Whole-abdominal Irradiation on Penetration Depth of Doxorubicin in Normal Tissue After Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) in a Post-mortem Swine Model.

    Science.gov (United States)

    Khosrawipour, Veria; Khosrawipour, Tanja; Hedayat-Pour, Yousef; Diaz-Carballo, David; Bellendorf, Alexander; Böse-Ribeiro, Hugo; Mücke, Ralph; Mohanaraja, Nirushika; Adamietz, Irenäus Anton; Fakhrian, Khashayar

    2017-04-01

    This study was performed to evaluate the impact of whole-abdominal irradiation on local penetration of doxorubicin into the peritoneum and the abdominal organs in a post-mortem swine model. Doxorubicin was aerosolized into the abdominal cavity of swine at a pressure of 12 mmHg CO2 at room temperature (25°). One swine was subjected to pressurized intraperitoneal aerosol chemotherapy (PIPAC) using Micropump(©) without irradiation; the second one received 2 Gy and the third one 7 Gy whole-abdominal irradiation, 15 min prior to PIPAC application. Samples of the peritoneal surface were extracted at different positions from within the abdominal cavity. In-tissue doxorubicin penetration was measured using fluorescence microscopy on frozen thin sections. The depth of penetration of doxorubicin was found to be wide-ranging, between 17 μm on the surface of the stomach and 348 μm in the small intestine. The penetration depth into the small intestine was 348 μm, 312 μm and 265 μm for PIPAC alone, PIPAC with 2 Gy irradiation and PIPAC with 7 Gy irradiation, respectively (pdoxorubicin penetration into normal tissue in the post-mortem swine model. A reduction of doxorubicin penetration was observed after application of higher irradiation doses. Further studies are warranted to determine if irradiation can be used safely as chemopotentiating agent for patients with peritoneal metastases treated with PIPAC. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  15. High Accuracy, Miniature Pressure Sensor for Very High Temperatures Project

    Data.gov (United States)

    National Aeronautics and Space Administration — SiWave proposes to develop a compact, low-cost MEMS-based pressure sensor for very high temperatures and low pressures in hypersonic wind tunnels. Most currently...

  16. Magnetic and Superconducting Materials at High Pressures

    Energy Technology Data Exchange (ETDEWEB)

    Struzhkin, Viktor V. [Carnegie Inst. of Washington, Washington, DC (United States)

    2015-03-24

    The work concentrates on few important tasks in enabling techniques for search of superconducting compressed hydrogen compounds and pure hydrogen, investigation of mechanisms of high-Tc superconductivity, and exploring new superconducting materials. Along that route we performed several challenging tasks, including discovery of new forms of polyhydrides of alkali metal Na at very high pressures. These experiments help us to establish the experimental environment that will provide important information on the high-pressure properties of hydrogen-rich compounds. Our recent progress in RIXS measurements opens a whole field of strongly correlated 3d materials. We have developed a systematic approach to measure major electronic parameters, like Hubbard energy U, and charge transfer energy Δ, as function of pressure. This technique will enable also RIXS studies of magnetic excitations in iridates and other 5d materials at the L edge, which attract a lot of interest recently. We have developed new magnetic sensing technique based on optically detected magnetic resonance from NV centers in diamond. The technique can be applied to study superconductivity in high-TC materials, to search for magnetic transitions in strongly correlated and itinerant magnetic materials under pressure. Summary of Project Activities; development of high-pressure experimentation platform for exploration of new potential superconductors, metal polyhydrides (including newly discovered alkali metal polyhydrides), and already known superconductors at the limit of static high-pressure techniques; investigation of special classes of superconducting compounds (high-Tc superconductors, new superconducting materials), that may provide new fundamental knowledge and may prove important for application as high-temperature/high-critical parameter superconductors; investigation of the pressure dependence of superconductivity and magnetic/phase transformations in 3d transition metal compounds, including

  17. Complications of high intensity focused ultrasound in patients with recurrent and metastatic abdominal tumors

    Institute of Scientific and Technical Information of China (English)

    Jian-Jun Li; Guo-Liang Xu; Mo-Fa Gu; Guang-Yu Luo; Zhang Rong; Pei-Hong Wu; Jian-Chuan Xia

    2007-01-01

    AIM: To analyze the local and systemic complications of high intensity focused ultrasound (HIFU) for patients with recurrent and metastatic abdominal tumors.METHODS: From Aug 2001 to Aug 2004, 17 patients with recurrent and metastatic abdominal tumors were enrolled in this study. Real-time sonography was taken, and vital signs, liver and kidney function, skin burns, local reactions, and systemic effects were observed and recored before, during, and after HIFU. CT and MRI were also taken before and after HIFU.RESULTS: All 17 patients had skin burns and pAln in the treatment region; the next common complication was neurapraxia of the stomach and intestines to variable degrees. The other local and systemic complications were relatively rare. Severe complications were present in two patients; one developed a superior mesenteric artery infarction resulting in necrosis of the entire small intestines, and the other one suffered from a perforation in terminal ileum due to HIFU treatment.CONCLUSION: Although HIFU is a one of noninvasive treatments for the recurrent and metastatic abdominal tumors, there are still some common and severe complications which need serious consideration.

  18. High pressure semiconductor physics I

    CERN Document Server

    Willardson, R K; Paul, William; Suski, Tadeusz

    1998-01-01

    Since its inception in 1966, the series of numbered volumes known as Semiconductors and Semimetals has distinguished itself through the careful selection of well-known authors, editors, and contributors. The "Willardson and Beer" Series, as it is widely known, has succeeded in publishing numerous landmark volumes and chapters. Not only did many of these volumes make an impact at the time of their publication, but they continue to be well-cited years after their original release. Recently, Professor Eicke R. Weber of the University of California at Berkeley joined as a co-editor of the series. Professor Weber, a well-known expert in the field of semiconductor materials, will further contribute to continuing the series' tradition of publishing timely, highly relevant, and long-impacting volumes. Some of the recent volumes, such as Hydrogen in Semiconductors, Imperfections in III/V Materials, Epitaxial Microstructures, High-Speed Heterostructure Devices, Oxygen in Silicon, and others promise indeed that this tra...

  19. High Blood Pressure: Medicines to Help You

    Science.gov (United States)

    ... names are given for the drugs in each group.Find your drug. Then read some basic information about your kind of drug. Types of High Blood Pressure Medicines ACE Inhibitors Beta Blockers Calcium Channel Blockers ...

  20. High Blood Pressure May Hike Dementia Risk

    Science.gov (United States)

    ... fullstory_161398.html High Blood Pressure May Hike Dementia Risk New statement from American Heart Association warns ... in middle age, might open the door to dementia, the American Heart Association warns in a new ...

  1. High-pressure oxidation of ethane

    DEFF Research Database (Denmark)

    Hashemi, Hamid; G. Jacobsen, Jon; Rasmussen, Christian T.

    2017-01-01

    Ethane oxidation at intermediate temperatures and high pressures has been investigated in both a laminar flow reactor and a rapid compression machine (RCM). The flow-reactor measurements at 600–900 K and 20–100 bar showed an onset temperature for oxidation of ethane between 700 and 825 K, depending...... as well as results at elevated pressure from literature. The experimental results and the modeling predictions do not support occurrence of NTC behavior in ethane oxidation. Even at the high-pressure conditions of the present work where the C2H5 + O2 reaction yields ethylperoxyl rather than C2H4 + HO2...

  2. Abdominal Cavity Eventration Treated by Means of the "Open Abdomen" Technique Using the Negative Pressure Therapy System--Case Report and Literature Review.

    Science.gov (United States)

    Trzeciak, Piotr W; Porzeżyńska, Joanna; Ptasińska, Karolina; Walczak, Dominik A

    2015-11-01

    Wound dehiscence is a surgical complication in which the wound ruptures along the surgical suture with abdominal cavity bowel displacement. It is observed in 0.2-6% of operated patients. The extensive wound is a gateway for infection. Moreover, increased secretion of serous fluid induces a hygienic problem and may lead to secondary skin infections or bedsores. The negative pressure wound therapy (NPWT) system is an innovative therapeutic method. It perfectly executes the TIME strategy, receiving more and more recognition. The study presented a case of a 62-year old male patient after several consecutive wound dehiscence episodes who was primarily treated for rectal cancer by means of low anterior resection of the rectum. Due to acute respiratory insufficiency after several operations, wound necrosis with dehiscence was observed. Considering the high risk of perioperative death we abandoned surgical treatment and introduced conservative management using negative pressure wound therapy until the patient's health improved. Literature regarding the above-mentioned issue was also reviewed.

  3. High pressure ceramic heat exchanger

    Science.gov (United States)

    Harkins, Bruce D.; Ward, Michael E.

    1998-01-01

    Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present header assembly when used with recuperators reduces the brittle effect of a portion of the ceramic components. Thus, the present header assembly used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present header assembly is comprised of a first ceramic member, a second ceramic member, a strengthening reinforcing member being in spaced relationship to the first ceramic member and the second ceramic member. The header assembly is further comprised of a refractory material disposed in contacting relationship with the first ceramic member, the second ceramic member and the strengthening reinforcing member. The present header assembly provides a high strength load bearing header assembly having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures.

  4. Elasticity of orthoenstatite at high-pressure

    Science.gov (United States)

    Zhang, D.; Jackson, J. M.; Chen, B.; Zhao, J.; Yan, J.

    2011-12-01

    Orthoenstatite is an abundant yet complex mineral in Earth's upper mantle. Despite its abundance, the properties of orthopyroxene at high pressure remain ambiguous (e.g., Zhang et al. 2011; Jahn 2008; Kung et al. 2004). We explored select properties of a synthetic powdered orthoenstatite (Mg0.8757Fe0.13)2Si2O6 sample by X-ray diffraction (XRD) and nuclear resonance inelastic X-ray scattering (NRIXS) as a function of pressure in a neon pressure medium at 300 K. The XRD measurements were carried out at beamline 12.2.2 of the Advanced Light Source (Berkeley, CA), and the sample was studied up to 34 GPa. NRIXS measurements were carried out at sector 3ID-B of the Advanced Photon Source (Chicago, IL) in the pressure range of 3 to 17 GPa. From the raw NRIXS data, the partial phonon density of states (DOS) was derived (e.g., Sturhahn 2004). The volume (or pressure) dependence of several properties, such as the Lamb-Mössbauer factor, mean force constant, specific heat, vibrational entropy, and vibrational kinetic energy were determined from the DOS. We will discuss our results from these combined studies and the implications for Earth's upper mantle. References Zhang, D., J.M. Jackson, W. Sturhahn, and Y. Xiao (2011): Local structure variations observed in orthoenstatite at high-pressures. American Mineralogist, in press. Jahn, S. (2008) High-pressure phase transitions in MgSiO3 orthoenstatite studied by atomistic computer simulation. American Mineralogist, 93(4), 528-532. Kung, J., Li, B., Uchida, T., Wang, Y., Neuville, D., and Liebermann, R. (2004) In situ measurements of sound velocities and densities across the orthopyroxene high-pressure clinopyroxene transition in MgSiO3 at high pressure. Physics of the Earth and Planetary Interiors, 147(1), 27-44. Sturhahn, W. (2004): Nuclear Resonant Spectroscopy. J. Phys. Condens. Matter, 16, S497-S530.

  5. High pressure optical combustion probe

    Energy Technology Data Exchange (ETDEWEB)

    Woodruff, S.D.; Richards, G.A.

    1995-06-01

    The Department of Energy`s Morgantown Energy Technology Center has developed a combustion probe for monitoring flame presence and heat release. The technology involved is a compact optical detector of the OH radical`s UV fluorescence. The OH Monitor/Probe is designed to determine the flame presence and provide a qualitative signal proportional to the flame intensity. The probe can be adjusted to monitor a specific volume in the combustion zone to track spatial fluctuations in the flame. The probe is capable of nanosecond time response and is usually slowed electronically to fit the flame characteristics. The probe is a sapphire rod in a stainless steel tube which may be inserted into the combustion chamber and pointed at the flame zone. The end of the sapphire rod is retracted into the SS tube to define a narrow optical collection cone. The collection cone may be adjusted to fit the experiment. The fluorescence signal is collected by the sapphire rod and transmitted through a UV transmitting, fused silica, fiber optic to the detector assembly. The detector is a side window photomultiplier (PMT) with a 310 run line filter. A Hamamatsu photomultiplier base combined with a integral high voltage power supply permits this to be a low voltage device. Electronic connections include: a power lead from a modular DC power supply for 15 VDC; a control lead for 0-1 volts to control the high voltage level (and therefore gain); and a lead out for the actual signal. All low voltage connections make this a safe and easy to use device while still delivering the sensitivity required.

  6. High-pressure oxidation of methane

    DEFF Research Database (Denmark)

    Hashemi, Hamid; Christensen, Jakob Munkholt; Gersen, Sander

    2016-01-01

    Methane oxidation at high pressures and intermediate temperatures was investigated in a laminar flow reactor and in a rapid compression machine (RCM). The flow-reactor experiments were conducted at 700–900 K and 100 bar for fuel-air equivalence ratios (Φ) ranging from 0.06 to 19.7, all highly...... diluted in nitrogen. It was found that under the investigated conditions, the onset temperature for methane oxidation ranged from 723 K under reducing conditions to 750 K under stoichiometric and oxidizing conditions. The RCM experiments were carried out at pressures of 15–80 bar and temperatures of 800......–1250 K under stoichiometric and fuel-lean (Φ=0.5) conditions. Ignition delays, in the range of 1–100 ms, decreased monotonically with increasing pressure and temperature. A chemical kinetic model for high-pressure methane oxidation was established, with particular emphasis on the peroxide chemistry...

  7. Structures of Liquid Aluminium under High Pressure

    Institute of Scientific and Technical Information of China (English)

    LI Hui; WANG Guang-Hou; BIAN Xiu-Fang; ZHANG Lin

    2001-01-01

    Molecular dynamics simulation has been carried out for melt A1 under constant temperature and constant pressure. The interaction between atoms is described by tight-binding many-body potentials based on the second moment approximation to the electronic density of states. The pair correlation function and the pair analysis technique are used to reveal the structural features of liquid Al under normal and high pressure. High pressure is favourable to the existence of bcc clusters 1661 and 1441, but has no effect on the fcc cluster 1421. The bond pair 1551 and 1541 with fivefold symmetry exists at high pressure. The microstructure of liquid is more similar to the non-crystalline structure than to the crystalline structure. The simulation results are supported by thex-ray experimental results.

  8. Tuberculosis abdominal Abdominal tuberculosis

    OpenAIRE

    Rubio, T.; M. T. Gaztelu; Calvo, A.; M. Repiso; H. Sarasíbar; F. Jiménez Bermejo; A. Martínez Echeverría

    2005-01-01

    La tuberculosis abdominal cursa con un cuadro inespecífico, con difícil diagnóstico diferencial respecto a otras entidades de similar semiología. Presentamos el caso de un varón que ingresa por presentar dolor abdominal, pérdida progresiva y notoria de peso corporal y fiebre de dos meses de evolución. El cultivo de la biopsia de colon mostró presencia de bacilo de Koch.Abdominal tuberculosis develops according to a non-specific clinical picture, with a difficult differential diagnosis with re...

  9. High pressure Raman scattering of silicon nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Khachadorian, Sevak; Scheel, Harald; Thomsen, Christian [Institut fuer Festkoerperphysik, Technische Universitaet Berlin, 10623 Berlin (Germany); Papagelis, Konstantinos [Materials Science Department, University of Patras, 26504 Patras (Greece); Colli, Alan [Nokia Research Centre, 21 J J Thomson Avenue, Cambridge CB3 0FA (United Kingdom); Ferrari, Andrea C, E-mail: khachadorian@physik.tu-berlin.de [Department of Engineering, University of Cambridge, Cambridge CB3 0FA (United Kingdom)

    2011-05-13

    We study the high pressure response, up to 8 GPa, of silicon nanowires (SiNWs) with {approx} 15 nm diameter, by Raman spectroscopy. The first order Raman peak shows a superlinear trend, more pronounced compared to bulk Si. Combining transmission electron microscopy and Raman measurements we estimate the SiNWs' bulk modulus and the Grueneisen parameters. We detect an increase of Raman linewidth at {approx} 4 GPa, and assign it to pressure induced activation of a decay process into LO and TA phonons. This pressure is smaller compared to the {approx} 7 GPa reported for bulk Si. We do not observe evidence of phase transitions, such as discontinuities or change in the pressure slopes, in the investigated pressure range.

  10. Abdominal Compartment Syndrome

    Directory of Open Access Journals (Sweden)

    Pınar Zeyneloğlu

    2015-04-01

    Full Text Available Intraabdominal hypertension and Abdominal compartment syndrome are causes of morbidity and mortality in critical care patients. Timely diagnosis and treatment may improve organ functions. Intra-abdominal pressure monitoring is vital during evaluation of the patients and in the management algorithms. The incidence, definition and risk factors, clinical presentation, diagnosis and management of intraabdominal hypertension and Abdominal compartment syndrome were reviewed here.

  11. High pressure studies of potassium perchlorate

    Science.gov (United States)

    Pravica, Michael; Wang, Yonggang; Sneed, Daniel; Reiser, Sharissa; White, Melanie

    2016-09-01

    Two experiments are reported on KClO4 at extreme conditions. A static high pressure Raman study was first conducted to 18.9 GPa. Evidence for at least two new phases was observed: one between 2.4 and 7.7 GPa (possibly sluggish), and the second near 11.7 GPa. Then, the X-ray induced decomposition rate of potassium perchlorate (KClO4 → hν KCl + 2O2) was studied up to 15.2 GPa. The time-dependent growth of KCl and O2 was monitored. The decomposition rate slowed at higher pressures. We present the first direct evidence for O2 crystallization at higher pressures, demonstrating that O2 molecules aggregate at high pressure.

  12. Abdominal Fat Accumulation with Hyperuricemia and Hypercholesterolemia Quail Model Induced by High Fat Diet

    Institute of Scientific and Technical Information of China (English)

    Zhi-jian Lin; Bing Zhang; Xiao-qing Liu; Hong-lian Yang

    2009-01-01

    Objective To establish abdominal fat accumulation with hyperuricemia and hypercholesterolemia quail model fed with high fat diet.And then to investigate the pathological characteristics of this quail model.Methods Thirty Longcheng quails were randomly divided into two groups:control group and model group(n=15).The control group quails were fed with normal diet and model group quails were fed with high fat diet for 14 days.After a 12-hour overnight fast,liver and abdominal fat at euthanasia as well as serum were collected.The levels of serum uric acid,total cholesterol,high density lipoprotein cholesterol (HDL-C),low density lipoprotein cholesterol(LDL-C),triglyceride,free fatty acid(FFA),and blood glucose were assayed.The activity changes of adenosine deaminase(ADA),xanthine oxidase(XOD),lipoprotein lipase(LPL),hepatic lipase(HL),and fatty acid synthetase(FAS)were analyzed.Results Comparcd with control group,the abdominal fat content(0.74±0.63 vs.1.36±0.65 g,P<0.05)and abdominal fat index(0.44% ±0.30% vs.0.85% ±0.30% ,P<0.01)as well as live lipid index (3.61% ±0.65% vs.11.33% ±2.14% ,P<0.01)in model group significantly increased;the levels of serum uric acid(210.61±94.76 vs.304.25±141.94 μmol/L,P<0.05),total cholesterol(4.20±0.51 vs.20.10±11.25 mmol/L,P<0.01),LDL-C(1.16±0.29 vs.10.78±6.48 mmol/L,P<0.01),and FFA(0.39±0.14 vs.0.55±0.15 mmol/L,P<0.01)in model group significantly increased;HDL-C(5.85±0.95 vs.4.14±2.03mmol/L,P<0.05)significantly decreased;the levels of triglyceride and blood glucose had no significant changes(P>0.05);the activities of ADA(9.71±3.05 vs.17.19±5.10 U/ml,P<0.01)and XOD(10.58±6.88vs.19.22±9.44 U/L,P<0.01)in model group significantly increased;and FAS,LPL,HL had no significant changes(P>0.05).Conclusions High fat diet can induce abdominal fat accumulation with hyperuricemia and hypercholesterolemia quail model.The changes of uric acid and lipid metabolic enzyme activities may be the pathological

  13. Reported high salt intake is associated with increased prevalence of abdominal aortic aneurysm and larger aortic diameter in older men.

    Directory of Open Access Journals (Sweden)

    Jonathan Golledge

    Full Text Available Salt intake has been implicated in the pathogenesis of abdominal aortic aneurysm (AAA through studies in rodent models but not previously studied in humans. The aim of this study was to examine the association between reported addition of salt to food and the prevalence of AAA.A risk factor questionnaire which contained a question about salt intake was included as part of a population screening study for AAA in 11742 older men. AAA presence was assessed by abdominal ultrasound imaging using a reproducible protocol.The prevalence of AAA was 6.9, 8.5 and 8.6% in men who reported adding salt to food never, sometimes and always, respectively, p = 0.005. Addition of salt to food sometimes (odds ratio [OR]: 1.22, 95% confidence interval [CI]: 1.03-1.44 or always (OR: 1.23, 95% CI 1.04-1.47 was independently associated with AAA after adjustment for other risk factors including age, waist-hip ratio, blood pressure, history of hypertension, high cholesterol, angina, diabetes, myocardial infarction and stroke. Salt intake was also independently associated with aortic diameter (beta 0.023, p = 0.012. In men with no prior history of hypertension, high cholesterol, angina, myocardial infarction or stroke (n = 4185, the association between addition of salt to food sometimes (OR: 1.41, 95% CI 0.96-2.08 or always (OR: 1.52, 95% CI 1.04-2.22 and AAA remained evident.Reported salt intake is associated with AAA in older men. Additional studies are needed to determine whether reducing salt intake would protect against AAA.

  14. High Temperature Dynamic Pressure Measurements Using Silicon Carbide Pressure Sensors

    Science.gov (United States)

    Okojie, Robert S.; Meredith, Roger D.; Chang, Clarence T.; Savrun, Ender

    2014-01-01

    Un-cooled, MEMS-based silicon carbide (SiC) static pressure sensors were used for the first time to measure pressure perturbations at temperatures as high as 600 C during laboratory characterization, and subsequently evaluated in a combustor rig operated under various engine conditions to extract the frequencies that are associated with thermoacoustic instabilities. One SiC sensor was placed directly in the flow stream of the combustor rig while a benchmark commercial water-cooled piezoceramic dynamic pressure transducer was co-located axially but kept some distance away from the hot flow stream. In the combustor rig test, the SiC sensor detected thermoacoustic instabilities across a range of engine operating conditions, amplitude magnitude as low as 0.5 psi at 585 C, in good agreement with the benchmark piezoceramic sensor. The SiC sensor experienced low signal to noise ratio at higher temperature, primarily due to the fact that it was a static sensor with low sensitivity.

  15. High temperature and pressure alkaline electrolysis

    DEFF Research Database (Denmark)

    Allebrod, Frank; Chatzichristodoulou, Christodoulos; Mogensen, Mogens Bjerg

    2013-01-01

    the operational temperature and pressure to produce pressurized hydrogen at high rate (m3 H2·h-1·m-2 cell area) and high electrical efficiency. This work describes an exploratory technical study of the possibility to produce hydrogen and oxygen with a new type of alkaline electrolysis cell at high temperatures...... for immobilization of aqueous KOH solutions. Electrolysis cells with this electrolyte and metal foam based gas diffusion electrodes were successfully demonstrated at temperatures up to 250 °C at 40 bar. Different electro-catalysts were tested in order to reduce the oxygen and hydrogen overpotentials. Current...

  16. Crystal structures at high pressures and temperatures

    Science.gov (United States)

    Caldwell, Wendel Alexander

    2000-10-01

    The diamond anvil cell (DAC) is a unique instrument that can generate pressures equivalent to those inside planetary interiors (pressures on the order of 1 million atmospheres) under sustained conditions. When combined with a bright source of collimated x-rays, the DAC can be used to probe the structure of materials in-situ at ultra-high pressures. An understanding of the high-pressure structure of materials is important in determining what types of processes may take place in the Earth at great depths. Motivated by previous studies showing that xenon becomes metallic at pressures above ˜1 megabar (100 GPa), we examined the stable structures and reactivity of xenon at pressures approaching that of the core-mantle boundary in the Earth. Our findings indicate the transformation of xenon from face-centered cubic (fcc) to hexagonal close-packed (hcp) structures is kinetically hindered at room temperature, with the equilibrium fcc--hcp phase boundary at 21 (+/-3) gigapascals, a pressure lower than was previously thought. Additionally, we find no tendency on the part of xenon to form a metal alloy with iron or platinum to at least 100 to 150 gigapascals, making it unlikely that the Earth's core serves as a reservoir for primordial xenon. Measurements of the compressibility of natural (Mg.75,Fe .25)2SiO4 gamma-spinel at pressures of the Earth's transition zone yield a pressure derivative of the bulk modulus K0 ' = 6.3 (+/-0.3). As gamma-spinel is considered to be a dominant mineral phase of the transition-zone of the Earth's mantle (400--670 km depth), the relatively high value of K0' for gamma-spinel may help explain the rapid increase with depth of seismic velocities through the transition zone. The thermodynamics, mechanisms and kinetics of pressure-induced amorphization are not well understood. We report here new studies indicating little or no entropy difference between the crystalline and glassy states of Ca(OH) 2 (portlandite). Additional work on the pressure

  17. High pressure, high current, low inductance, high reliability sealed terminals

    Science.gov (United States)

    Hsu, John S [Oak Ridge, TN; McKeever, John W [Oak Ridge, TN

    2010-03-23

    The invention is a terminal assembly having a casing with at least one delivery tapered-cone conductor and at least one return tapered-cone conductor routed there-through. The delivery and return tapered-cone conductors are electrically isolated from each other and positioned in the annuluses of ordered concentric cones at an off-normal angle. The tapered cone conductor service can be AC phase conductors and DC link conductors. The center core has at least one service conduit of gate signal leads, diagnostic signal wires, and refrigerant tubing routed there-through. A seal material is in direct contact with the casing inner surface, the tapered-cone conductors, and the service conduits thereby hermetically filling the interstitial space in the casing interior core and center core. The assembly provides simultaneous high-current, high-pressure, low-inductance, and high-reliability service.

  18. Abdominal Cavity Eventration Treated by Means of the „Open Abdomen” Technique Using the Negative Pressure Therapy System – Case Report and Literature Review

    OpenAIRE

    Trzeciak Piotr W.; Porzeżyńska Joanna; Ptasińska Karolina; Walczak Dominik A.

    2015-01-01

    Wound dehiscence is a surgical complication in which the wound ruptures along the surgical suture with abdominal cavity bowel displacement. It is observed in 0.2-6% of operated patients. The extensive wound is a gateway for infection. Moreover, increased secretion of serous fluid induces a hygienic problem and may lead to secondary skin infections or bedsores. The negative pressure wound therapy (NPWT) system is an innovative therapeutic method. It perfectly executes the TIME strategy, receiv...

  19. Arterial enhancement at abdominal CT angiography: Low- versus high-osmolality contrast media

    Energy Technology Data Exchange (ETDEWEB)

    Rouviere, O.; Berger, P.; Pangaud, C.; Lyonnet, D. [Hopital E. Herriot, Lyon (France). Dept. of Vascular and Genitourinary Radiology; Ecochard, R. [Hospices Civils de Lyon (France). Dept of Biostatistics; Fontaine, B. [Laboratoire Guerbet, Roissy (France)

    2000-09-01

    Purpose: To evaluate the effects of contrast media pharmokinetic differences on aortic enhancement at abdominal CT angiography and to determine whether these effects are of clinical relevance. Material and Methods: Two hundred and twelve patients referred for abdominal CT angiography were included in the study. All abdominal CT angiograms were performed with the same parameters (collimation 3 mm, pitch ratio 1.7, scan delay 30 s) after i.v. injection of 120 ml of contrast medium at 3 ml/s. After randomization, patients received either iobitridol 300 (low-osmolar, 300 mg I/ml), iobitridol 350 (low-osmolar, 350 mg I/ml) or ioxithalamate 350 (high-osmolar, 350 mg I/ml). The time attenuation curves obtained with the three contrast media were compared. Results: The time attenuation curve obtained with ioxithalamate 350 was not parallel to those obtained with iobitridol 300 and iobitridol 350. Mean peak enhancements obtained with iobitridol 350 and ioxithalamate 350 were not significantly different but iobitridol 350 provided higher mean peak enhancement than iobitridol 300. Mean delays of the peak enhancements were the same with the three contrast media. After peak enhancement, the decrease of aortic opacification under a selected threshold of 200 HU was significantly slower with iobitridol 350 than with iobitridol 300 and ioxithalamate 350, whereas iobitridol 300 and ioxithalamate 350 showed no significant differences. Conclusion: For a given iodine concentration, low-osmolality contrast media provide longer aortic opacification and may be recommended for CT angiography when long acquisition times are needed.

  20. Very-high-flow injection rate for upper abdominal CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, Masashi; Minamiguti, Hiroki; Hagihira, Takami; Kishi, Kazushi; Sato, Morio [Wakayama Medical Coll. (Japan); Shioyama, Yasukazu; Okumura, Toshiyuki; Yamada, Kouji; Kawashima, Michihisa [Central Hospital and Cancer Center of Ibaraki Prefecture, Tomobe (Japan)

    2002-06-01

    The purpose of this study was to compare a very-high-flow injection-rate method (group A) and a conventional injection-rate method (group B) for visualization of upper abdominal arteries by multidetector helical computed tomography (MDHCT). The subjects were 240 patients suspected to have abdominal lesions. They were randomly assigned to group A (120 patients) and group B (120 patients). In group A, the bilateral medial cubital veins were punctured, and contrast medium was infused at a rate of 8.6-9.6 ml/s. In group B, the unilateral medial cubital vein was punctured, and contrast medium was infused at a rate of 2.0-3.0 ml/s. The quality of vascular visualization was graded as poor, good, or excellent by three radiologists. All visualizations of the celiac trunk (CE) and superior mesenteric artery (SMA) were graded as excellent in both group A and group B. Visualization grades of the subsegmental branches of the hepatic artery (HA), right gastric artery (RGA), cystic artery, dorsal pancreatic artery (DPA), and superior pancreaticoduodenal artery (SPDA) were good or excellent in 75% (paging method)/53.3% (three-dimensional method), 85%/30%, 77.7%/18.3%, 76.7%/28.3%, and 88.3%/42.5%, respectively, in group A, and 33.3%/11.7%, 46.7%/3.4%, 41.6%/5%, 55%/4.2%, and 72.5%/14.2%, respectively, in group B. The appearance rate of intrahepatic portal branches was 28.3% in group A and 66.7% in group B in the arterial dominant phase. Group A showed better visualization results than Group B in upper abdominal arteries according to MDHCT. (author)

  1. Curved and conformal high-pressure vessel

    Energy Technology Data Exchange (ETDEWEB)

    Croteau, Paul F.; Kuczek, Andrzej E.; Zhao, Wenping

    2016-10-25

    A high-pressure vessel is provided. The high-pressure vessel may comprise a first chamber defined at least partially by a first wall, and a second chamber defined at least partially by the first wall. The first chamber and the second chamber may form a curved contour of the high-pressure vessel. A modular tank assembly is also provided, and may comprise a first mid tube having a convex geometry. The first mid tube may be defined by a first inner wall, a curved wall extending from the first inner wall, and a second inner wall extending from the curved wall. The first inner wall may be disposed at an angle relative to the second inner wall. The first mid tube may further be defined by a short curved wall opposite the curved wall and extending from the second inner wall to the first inner wall.

  2. Superconductivity from insulating elements under high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Katsuya

    2015-07-15

    Highlights: • Even insulating molecule can become metal and superconductor by pressure with relatively high T{sub c}. • The highest T{sub c} is observed in sulfur with 17 K at 160 GPa. • Hydrogen is the best candidate of the highest T{sub c} element. - Abstract: The insulating and superconducting states would seem to have very different characteristics. Can any insulator become a superconductor? One proven method, doping an insulating material with carriers, can create itinerant states inside the gap between the conduction and valence bands. Another method is to squeeze the structure by applying pressure. Pressure can expand the bandwidth and also narrow the energy band gap. So the first step to turn an insulator into a superconductor is to make it metallic. Here we review our experimental research and results on superconductivity induced by applying pressure to insulating molecular systems such as elemental molecules.

  3. Impact of abdominal obesity and ambulatory blood pressure in the diagnosis of left ventricular hypertrophy in never treated hypertensives.

    Science.gov (United States)

    Rodilla, Enrique; Costa, José A; Martín, Joaquin; González, Carmen; Pascual, Jose M; Redon, Josep

    2014-03-20

    The principal objective was to assess the prevalence of left ventricular hypertrophy (LVH) in hypertensive, never treated patients, depending on adjustment for body surface or height. Secondary objectives were to determine geometric alterations of the left ventricle and to analyze the interdependence of hypertension and obesity to induce LVH. Cross-sectional study that included 750 patients (387 men) aged 47 (13, SD) years who underwent ambulatory blood pressure (ABPM) monitoring and echocardiography. The prevalence of LVH was 40.4% (303 patients), adjusted for body surface area (BSA, LVHBSA), and 61.7% (463 patients), adjusted for height(2.7) (LVHheight(2.7)). In a multivariate logistic analysis, systolic BP24h, gender and presence of elevated microalbuminuria were associated with both LVHBSA and LVHheight(2.7). Increased waist circumference was the strongest independent predictor of LVHheight(2.7), but was not associated with LVHBSA. We found a significant interaction between abdominal obesity and systolic BP24h in LVHheight(2.7). Concentric remodelling seems to be the most prevalent alteration of left ventricular geometry in early stages of hypertension (37.5%). The impact of obesity as predictor of LVH in never treated hypertensives is present only when left ventricular mass (LVM) is indexed to height(2.7). Obesity interacts with systolic BP24h in an additive but not merely synergistic manner. Systolic BP24h is the strongest determinant of LVH when indexed for BSA. Copyright © 2012 Elsevier España, S.L. All rights reserved.

  4. High pressure water jet cutting and stripping

    Science.gov (United States)

    Hoppe, David T.; Babai, Majid K.

    1991-01-01

    High pressure water cutting techniques have a wide range of applications to the American space effort. Hydroblasting techniques are commonly used during the refurbishment of the reusable solid rocket motors. The process can be controlled to strip a thermal protective ablator without incurring any damage to the painted surface underneath by using a variation of possible parameters. Hydroblasting is a technique which is easily automated. Automation removes personnel from the hostile environment of the high pressure water. Computer controlled robots can perform the same task in a fraction of the time that would be required by manual operation.

  5. High temperature and pressure alkaline electrolysis

    DEFF Research Database (Denmark)

    Allebrod, Frank; Chatzichristodoulou, Christodoulos; Mogensen, Mogens Bjerg

    2013-01-01

    and pressures. Two measurement systems were built to perform measurements under high pressures and at elevated temperatures of up to 95 bar and 250 °C, respectively. The conductivity of aqueous KOH and aqueous KOH immobilized in a porous SrTiO3 structure were investigated at elevated temperatures and high...... the operational temperature and pressure to produce pressurized hydrogen at high rate (m3 H2·h-1·m-2 cell area) and high electrical efficiency. This work describes an exploratory technical study of the possibility to produce hydrogen and oxygen with a new type of alkaline electrolysis cell at high temperatures...... concentrations of the electrolyte using the van der Pauw method in combination with electrochemical impedance spectroscopy (EIS). Conductivity values as high as 2.9 S cm-1 for 45 wt% KOH aqueous KOH and 0.84 S cm-1 for the immobilized KOH of the same concentration were measured at 200 °C. Porous SrTiO3 was used...

  6. Multidisciplinary perioperative protocol in patients undergoing acute high-risk abdominal surgery

    DEFF Research Database (Denmark)

    Toft Tengberg, Line; Bay-Nielsen, M; Bisgaard, T;

    2017-01-01

    BACKGROUND: Acute high-risk abdominal (AHA) surgery carries a very high risk of morbidity and mortality and represents a massive healthcare burden. The aim of the present study was to evaluate the effect of a standardized multidisciplinary perioperative protocol in patients undergoing AHA surgery...... after initiation of the AHA protocol as standard care. The intervention cohort was compared with a predefined, consecutive historical cohort of patients from the same department. The protocol involved continuous staff education, consultant-led attention and care, early resuscitation and high......-dose antibiotics, surgery within 6 h, perioperative stroke volume-guided haemodynamic optimization, intermediate level of care for the first 24 h after surgery, standardized analgesic treatment, early postoperative ambulation and early enteral nutrition. The primary outcome was 30-day mortality. RESULTS: Six...

  7. High pressure effects on allergen food proteins.

    Science.gov (United States)

    Somkuti, Judit; Smeller, László

    2013-12-15

    There are several proteins, which can cause allergic reaction if they are inhaled or ingested. Our everyday food can also contain such proteins. Food allergy is an IgE-mediated immune disorder, a growing health problem of great public concern. High pressure is known to affect the structure of proteins; typically few hundred MPa pressure can lead to denaturation. That is why several trials have been performed to alter the structure of the allergen proteins by high pressure, in order to reduce its allergenicity. Studies have been performed both on simple protein solutions and on complex food systems. Here we review those allergens which have been investigated under or after high pressure treatment by methods capable of detecting changes in the secondary and tertiary structure of the proteins. We focus on those allergenic proteins, whose structural changes were investigated by spectroscopic methods under pressure in correlation with the observed allergenicity (IgE binding) changes. According to this criterion we selected the following allergen proteins: Mal d 1 and Mal d 3 (apple), Bos d 5 (milk), Dau c 1 (carrot), Gal d 2 (egg), Ara h 2 and Ara h 6 (peanut), and Gad m 1 (cod).

  8. High pressure effects in anaesthesia and narcosis.

    Science.gov (United States)

    Wlodarczyk, Agnieszka; McMillan, Paul F; Greenfield, Susan A

    2006-10-01

    There is growing interest in determining the effects of high pressure on biological functions. Studies of brain processes under hyperbaric conditions can give a unique insight into phenomena such as nitrogen narcosis, inert gas anaesthesia, and pressure reversal of the effects of anaesthetic and narcotic agents. Such research may shed light on the action of anaesthetics, which remains poorly understood, and on the nature of consciousness itself. Various studies have established the behavioural response of organisms to hyperbaric conditions, in the presence or absence of anaesthetic agents. At the molecular level, X-ray crystallography has been used to investigate the incorporation of species like Xe in hydrophobic pockets within model ion channels that may account for pressure effects on neuronal transmission. New magnetic resonance imaging techniques are providing tomographic three-dimensional images that detail brain structure and function, and that can be correlated with behavioural studies and psychological test results. Such whole organ techniques are linked to the molecular scale via voltage-sensitive dye (VSD) imaging studies on brain slices that provide time-resolved images of the dynamic formation and interconnection of inter-neuronal complexes. The VSD experiments are readily adapted to in situ studies under high pressure conditions. In this tutorial review we review the current state of knowledge of hyperbaric effects on brain processes: anaesthesia and narcosis, recent studies at the molecular level via protein crystallography at high pressure in a Xe atmosphere, and we also present some preliminary results of VSD imaging of brain slices under hyperbaric conditions.

  9. Introduction to High-Pressure Science

    Science.gov (United States)

    Dera, Przemyslaw

    To a common person pressure is just one of the parameters that describe a thermodynamic state. We all hear about it in everyday weather forecasts, and most of us do not associate it with anything particularly unique. Probably the most intuitive idea of the effect of high-pressure comes from movies, where submarine sinking to the bottom of the ocean is gradually crushed by the surrounding water, until its hull implodes. Why, then hundreds of scientists throughout the world spent their lifelong careers studying high-pressure phenomena? Despite all the developments in experimental technologies and instrumentation, modern scientist has very few tools that allow him or her to "grab" two atoms and bring them, in a very controllable way, closer together. Being able to achieve this task means the ability to directly probe interatomic interaction potentials and can cause transformations as dramatic as turning of a common gas into solid metal. Before the reader delves into more advanced topics described later in this book, this introductory chapter aims to explain several elementary, but extremely important concepts in high-pressure science. We will start with a brief discussion of laboratory devices used to produce pressure, address the issue of hydrostaticity, elastic and plastic compression, and will conclude with a short discussion of unique effects of anisotropic stress.

  10. HIGH PRESSURE COAL COMBUSTON KINETICS PROJECT

    Energy Technology Data Exchange (ETDEWEB)

    Stefano Orsino

    2005-03-30

    As part of the U.S. Department of Energy (DoE) initiative to improve the efficiency of coal-fired power plants and reduce the pollution generated by these facilities, DOE has funded the High-Pressure Coal Combustion Kinetics (HPCCK) Projects. A series of laboratory experiments were conducted on selected pulverized coals at elevated pressures with the specific goals to provide new data for pressurized coal combustion that will help extend to high pressure and validate models for burnout, pollutant formation, and generate samples of solid combustion products for analyses to fill crucial gaps in knowledge of char morphology and fly ash formation. Two series of high-pressure coal combustion experiments were performed using SRI's pressurized radiant coal flow reactor. The first series of tests characterized the near burner flame zone (NBFZ). Three coals were tested, two high volatile bituminous (Pittsburgh No.8 and Illinois No.6), and one sub-bituminous (Powder River Basin), at pressures of 1, 2, and 3 MPa (10, 20, and 30 atm). The second series of experiments, which covered high-pressure burnout (HPBO) conditions, utilized a range of substantially longer combustion residence times to produce char burnout levels from 50% to 100%. The same three coals were tested at 1, 2, and 3 MPa, as well as at 0.2 MPa. Tests were also conducted on Pittsburgh No.8 coal in CO2 entrainment gas at 0.2, 1, and 2 MPa to begin establishing a database of experiments relevant to carbon sequestration techniques. The HPBO test series included use of an impactor-type particle sampler to measure the particle size distribution of fly ash produced under complete burnout conditions. The collected data have been interpreted with the help of CFD and detailed kinetics simulation to extend and validate devolatilization, char combustion and pollutant model at elevated pressure. A global NOX production sub-model has been proposed. The submodel reproduces the performance of the detailed chemical

  11. Photophysics of organic molecules at high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Dean James

    1978-01-01

    The pressure dependence of emission intensities, energies, and lifetimes of several classes of organic compounds in plastic media were investigated over the range 0-140 kilobars. The fluorescence intensity of 9-anthraldehyde, 9-acetylanthracene, and 9-benzoylanthracene increases remarkably with increasing pressure, accompanied by a large red shift in the emission spectrum. For azulene and several derivatives, the efficiency of fluorescence from both the second and first excited singlet states was pressure dependent as was the relative energy of these states. The rate of internal conversion depended strongly on the energy separating the relevant states. The energy and quantum efficiency of fluorescence for fluorenone in crystalline form and in several polymeric matrices was measured as a function of pressure. The quantum yield, ranged from 0.001 at low pressure to a maximum of about 0.1 at high pressure in paraffinic plastics. Fluorescence quantum yields and phosphorescence quantum yields and lifetimes were measured for pyrazine (P) 2,6-dimethylpyrazine and tetramethylpyrazine (TMP) in PMMA over the pessure range 20-120 kbar. An additional emission, which is attributed to excimer fluorescence, was also observed for these samples and for crystalline pyrazine. The phosphorescence radiative lifetime for P and TMP was about 18 ms.

  12. High temperature and pressure electrochemical test station

    DEFF Research Database (Denmark)

    Chatzichristodoulou, Christodoulos; Allebrod, Frank; Mogensen, Mogens Bjerg

    2013-01-01

    An electrochemical test station capable of operating at pressures up to 100 bars and temperatures up to 400 ◦C has been established. It enables control of the partial pressures and mass flow of O2, N2, H2, CO2, and H2O in a single or dual environment arrangement, measurements with highly corrosive...... media, as well as localized sampling of gas evolved at the electrodes for gas analysis. A number of safety and engineering design challenges have been addressed. Furthermore, we present a series of electrochemical cell holders that have been constructed in order to accommodate different types of cells......, to the electrochemical characterization of high temperature and pressure alkaline electrolysis cells and the use of pseudo-reference electrodes for the separation of each electrode contribution. A future perspective of various electrochemical processes and devices that can be developed with the use of the established...

  13. Blue emitting organic semiconductors under high pressure

    DEFF Research Database (Denmark)

    Knaapila, Matti; Guha, Suchismita

    2016-01-01

    This review describes essential optical and emerging structural experiments that use high GPa range hydrostatic pressure to probe physical phenomena in blue-emitting organic semiconductors including π-conjugated polyfluorene and related compounds. The work emphasizes molecular structure...... and intermolecular self-organization that typically determine transport and optical emission in π-conjugated oligomers and polymers. In this context, hydrostatic pressure through diamond anvil cells has proven to be an elegant tool to control structure and interactions without chemical intervention. This has been...... and intermolecular interactions on optical excitations, electron–phonon interaction, and changes in backbone conformations. This picture is connected to the optical high pressure studies of other π-conjugated systems and emerging x-ray scattering experiments from polyfluorenes which provides a structure-property map...

  14. High pressure photophysics of organic molecules

    Energy Technology Data Exchange (ETDEWEB)

    Brey, L. A.

    1979-01-01

    High pressure spectroscopic studies on several classes of organic compounds were made both in fluid solution (to 10 kbar) and in polymeric media (to 40 kbar). The first three studies were conducted in fluid solution and concern the effect of solvent viscosity on the nonradiative deactivation rates from electronically excited states. Pressure was utilized to attain high viscosities in organic solvents at room temperature. The primary experimental technique used was fluorescence emission spectroscopy. In the fourth and last study observations were made both in fluid solution and in plastic films. The focus of this study was the effect of pressure on the solvent-chromophore dispersion interaction in several polyenes and the concomitant changes in both the radiative and non-radiative rates from the excited states. Extensive use was made of fluorescence lifetime measurements and excitation spectra. 105 references.

  15. Too Many Americans Have High Blood Pressure, Doctors Warn

    Science.gov (United States)

    ... news/fullstory_163468.html Too Many Americans Have High Blood Pressure, Doctors Warn With February designated National Heart Month, ... physicians warns that too many Americans struggle with high blood pressure. High blood pressure is a major risk factor ...

  16. Advanced Diagnostics for High Pressure Spray Combustion.

    Energy Technology Data Exchange (ETDEWEB)

    Skeen, Scott A.; Manin, Julien Luc; Pickett, Lyle M.

    2014-06-01

    The development of accurate predictive engine simulations requires experimental data to both inform and validate the models, but very limited information is presently available about the chemical structure of high pressure spray flames under engine- relevant conditions. Probing such flames for chemical information using non- intrusive optical methods or intrusive sampling techniques, however, is challenging because of the physical and optical harshness of the environment. This work details two new diagnostics that have been developed and deployed to obtain quantitative species concentrations and soot volume fractions from a high-pressure combusting spray. A high-speed, high-pressure sampling system was developed to extract gaseous species (including soot precursor species) from within the flame for offline analysis by time-of-flight mass spectrometry. A high-speed multi-wavelength optical extinction diagnostic was also developed to quantify transient and quasi-steady soot processes. High-pressure sampling and offline characterization of gas-phase species formed following the pre-burn event was accomplished as well as characterization of gas-phase species present in the lift-off region of a high-pressure n-dodecane spray flame. For the initial samples discussed in this work several species were identified, including polycyclic aromatic hydrocarbons (PAH); however, quantitative mole fractions were not determined. Nevertheless, the diagnostic developed here does have this capability. Quantitative, time-resolved measurements of soot extinction were also accomplished and the novel use of multiple incident wavelengths proved valuable toward characterizing changes in soot optical properties within different regions of the spray flame.

  17. Cobalt ferrite nanoparticles under high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Saccone, F. D.; Ferrari, S.; Grinblat, F.; Bilovol, V. [Instituto de Tecnologías y Ciencias de la Ingeniería, “Ing. H. Fernández Long,” Av. Paseo Colón 850 (1063), Buenos Aires (Argentina); Errandonea, D., E-mail: daniel.errandonea@uv.es [Departamento de Fisica Aplicada, Institut Universitari de Ciència dels Materials, Universitat de Valencia, c/ Doctor Moliner 50, E-46100 Burjassot, Valencia (Spain); Agouram, S. [Departamento de Física Aplicada y Electromagnetismo, Universitat de València, 46100 Burjassot, Valencia (Spain)

    2015-08-21

    We report by the first time a high pressure X-ray diffraction and Raman spectroscopy study of cobalt ferrite (CoFe{sub 2}O{sub 4}) nanoparticles carried out at room temperature up to 17 GPa. In contrast with previous studies of nanoparticles, which proposed the transition pressure to be reduced from 20–27 GPa to 7.5–12.5 GPa (depending on particle size), we found that cobalt ferrite nanoparticles remain in the spinel structure up to the highest pressure covered by our experiments. In addition, we report the pressure dependence of the unit-cell parameter and Raman modes of the studied sample. We found that under quasi-hydrostatic conditions, the bulk modulus of the nanoparticles (B{sub 0} = 204 GPa) is considerably larger than the value previously reported for bulk CoFe{sub 2}O{sub 4} (B{sub 0} = 172 GPa). In addition, when the pressure medium becomes non-hydrostatic and deviatoric stresses affect the experiments, there is a noticeable decrease of the compressibility of the studied sample (B{sub 0} = 284 GPa). After decompression, the cobalt ferrite lattice parameter does not revert to its initial value, evidencing a unit cell contraction after pressure was removed. Finally, Raman spectroscopy provides information on the pressure dependence of all Raman-active modes and evidences that cation inversion is enhanced by pressure under non-hydrostatic conditions, being this effect not fully reversible.

  18. Overall and abdominal obesity indicators had different association with central arterial stiffness and hemodynamics independent of age, sex, blood pressure, glucose, and lipids in Chinese community-dwelling adults

    Directory of Open Access Journals (Sweden)

    Fu S

    2013-11-01

    Full Text Available Shihui Fu,1 Leiming Luo,1 Ping Ye,1 Yuan Liu,1 Bing Zhu,1 Jin Zheng,1 Yongyi Bai,1 Jie Bai21Department of Geriatric Cardiology, 2Department of Clinical Biochemistry, Chinese People’s Liberation Army General Hospital, Beijing, People’s Republic of ChinaObjective: Limited large sample studies have specially compared overall and abdominal obesity in relation to central arterial stiffness and hemodynamics in community-dwelling adults, especially in the People's Republic of China. This study aimed to compare the relationship between an overall obesity indicator (body mass index [BMI], an abdominal obesity index (waist circumference [WC], and central arterial stiffness and hemodynamics, independent of age, sex, blood pressure, glucose, and lipids, in Chinese community-dwelling adults.Methods: For 2,624 adults in this study, anthropometric indices, such as BMI and WC, were measured. Central arterial stiffness was assessed by carotid-femoral pulse wave velocity (cfPWV. Central hemodynamics was represented by central pulse pressure (cPP.Results: Both overall and abdominally obese adults were older, with significantly higher cfPWV, cPP, peripheral pulse pressure (pPP, fasting blood glucose (FBG, and low-density lipoprotein-cholesterol (LDL-C, and significantly lower high-density lipoprotein-cholesterol (HDL-C. After adjusting for age and sex, both the overall and abdominally obese individuals had independently higher pPP, FBG, and LDL-C levels, and lower HDL-C level. The overall obese individuals had independently higher cPP, but not cfPWV, after adjusting for age and sex, while the abdominally obese individuals had independently higher cfPWV, but not cPP. After adjusting for age, sex, pPP, FBG, LDL-C, and HDL-C, WC, but not BMI, was independently correlated with cfPWV, and BMI, but not WC, was independently associated with cPP. Age, sex, pPP, FBG, and HDL-C levels have independent association with cfPWV. Age, sex, pPP, but not FBG and HDL-C levels

  19. Influência do índice de massa corporal e da circunferência abdominal na pressão arterial sistêmica de crianças Influence of body mass index and abdominal circumference on children's systemic blood pressure

    Directory of Open Access Journals (Sweden)

    Marcelo Nunes Iampolsky

    2010-06-01

    Full Text Available OBJETIVO: Avaliar os níveis pressóricos em crianças e relacioná-los ao índice de massa corporal e à circunferência abdominal. MÉTODOS: Por meio de estudo prospectivo e transversal, avaliaram-se 1.408 escolares com idade entre cinco anos e dez anos e 11 meses, matriculados em escolas públicas do Município de Santo André. Foram coletados: peso ao nascer; peso e estatura, expressos como escore Z do índice de massa corporal (ZIMC e estatura para idade (ZEI. A pressão arterial (medida única foi aferida pelo mesmo examinador. Considerou-se: desnutrição quando ZIMC+2, baixa estatura se ZEIP90 para sexo e idade e pressão arterial elevada quando superior ao percentil 90 para sexo, idade e estatura. A análise estatística incluiu o teste do qui-quadrado e o cálculo da Odds Ratio, adotando-se como significante o valor de pOBJECTIVE: To evaluate blood pressure levels in children, relating them to body mass index and abdominal circumference. METHODS: This cross-sectional prospective study enrolled 1.408 school children, aged between five and ten years and 11 months, in the municipality of Santo Andre, São Paulo, Brazil. The following variables were evaluated: birth weight, weight and height, expressed as body mass index Z score (ZBMI and height to age Z score (ZH, and waist circumference (WC. Blood pressure was measured once by the same physician. Malnutrition was considered when ZBMI +2, short stature when ZH P90 for age and gender, and increased blood pressure when >P90 for age, gender and height. Statistical analysis included chi-square test and Odds Ratio, being significant p<0.05. RESULTS: Mean age was seven years old, and 51% were females. High systolic blood pressure levels were observed in 19% and elevated diastolic blood pressure in 12%. Short stature, malnutrition, obesity and increased abdominal circumference were diagnosed in 2.6%, 3.1%, 7.3% and 13.4%, respectively, of the studied population. The presence of obesity was

  20. Nanoshells as a high-pressure gauge

    Science.gov (United States)

    Tempere, Jacques; van den Broeck, Nick; Putteneers, Katrijn; Silvera, Isaac

    2012-02-01

    Nanoshells, consisting of multiple spherical layers, have an extensive list of applications, usually performing the function of a probe. We add a new application to this list in the form of a high-pressure gauge in a Diamond Anvil Cell (DAC). In a DAC, where high pressures are reached by pressing two diamonds together, existing gauges fail at higher pressures because of calibration difficulties and obscuring effects in the diamonds. The nanoshell gauge does not face this issue since its optical spectrum can be engineered by altering the thickness of its layers. Furthermore their properties are measured by broad band optical transmission spectroscopy leading to a very large signal-to-noise ratio even in the multi-megabar pressure regime where ruby measurements become challenging. Theoretical calculations based on the Maxwell equations in a spherical geometry combined with the Vinet equation of state show that a three-layer geometry (SiO2-Au-SiO2) indeed has a measurable pressure-dependent optical response desirable for gauges.

  1. Diagnostics of a High Pressure Helium Microplasma

    Science.gov (United States)

    Wang, Qiang; Koleva, Ivanka; Economou, Demetre; Donnelly, Vincent

    2004-09-01

    Gas and plasma diagnostics were performed in a slot-type DC microplasma (200 microns gap) discharge at high pressures. The gas temperature in a helium discharge was estimated by adding small quantities of nitrogen (excimer. At 250 Torr pressure and 200 mA/cm2 current density, the gas temperature was Tg = 350 +/- 25 K. The measured gas temperature was almost independent (to within experimental uncertainty) of pressure (in the range of 150 Torr - 600 Torr), and current density (in the range of 100 mA/cm2 - 400 mA/cm2). These measurements were consistent with a simple heat transfer model. Spatially resolved measurements of electron temperature were also performed using trace rare gas optical emission actinometry (TRG-OES). These measurements are greatly complicated by collisional quenching at the high operating pressures. Electron density and electron temperature profiles was deduced by comparing emission intensities from the Paschen 2px (x = 1-10) manifold of Ne, Ar, Kr and Xe trace gases. Results suggested that the electron temperature peaks in the cathode sheath region, while the plasma density peaks away from the cathode sheath. A self-consistent fluid model of a DC helium microdischarge was in agreement with the experimental data. The model was used to study the dependence of discharge characteristics on operating conditions (pressure, gap spacing, current density, etc.).

  2. Abdominal Decompression in Children

    Directory of Open Access Journals (Sweden)

    J. Chiaka Ejike

    2012-01-01

    Full Text Available Abdominal compartment syndrome (ACS increases the risk for mortality in critically ill children. It occurs in association with a wide variety of medical and surgical diagnoses. Management of ACS involves recognizing the development of intra-abdominal hypertension (IAH by intra-abdominal pressure (IAP monitoring, treating the underlying cause, and preventing progression to ACS by lowering IAP. When ACS is already present, supporting dysfunctional organs and decreasing IAP to prevent new organ involvement become an additional focus of therapy. Medical management strategies to achieve these goals should be employed but when medical management fails, timely abdominal decompression is essential to reduce the risk of mortality. A literature review was performed to understand the role and outcomes of abdominal decompression among children with ACS. Abdominal decompression appears to have a positive effect on patient survival. However, prospective randomized studies are needed to fully understand the indications and impact of these therapies on survival in children.

  3. Teaming Up Against High Blood Pressure

    Centers for Disease Control (CDC) Podcasts

    2012-09-04

    This podcast is based on the September 2012 CDC Vital Signs report. A team-based approach by patients, health care systems, and health care providers is one of the best ways to treat uncontrolled high blood pressure.  Created: 9/4/2012 by Centers for Disease Control and Prevention (CDC).   Date Released: 9/4/2012.

  4. High Pressure Inactivation of HAV within Mussels

    Science.gov (United States)

    The potential of hepatitis A virus (HAV) to be inactivated within Mediterranean mussels (Mytilus galloprovincialis) and blue mussels (Mytilus edulis) by high pressure processing was evaluated. HAV was bioaccumulated within mussels to approximately 6-log10 PFU by exposure of mussels to HAV-contamina...

  5. High pressure and synchrotron radiation satellite workshop

    Energy Technology Data Exchange (ETDEWEB)

    Bass, J.; Guignot, N.; Morard, G.; Mezouar, M.; Andrault, D.; Bolfan-Casanova, N.; Sturhahn, W.; Daniel, I.; Reynard, B.; Simionovici, A.; Sanchez Valle, C.; Martinez, I.; Kantor, I.; Dubrovinsky, I.; Mccammon, C.; Dubrovinskaia, N.; Kurnosiv, A.; Kuznetsov, A.; Goncharenko, I.; Loubeyre, P.; Desgreniers, S.; Weck, G.; Yoo, C.S.; Iota, V.; Park, J.; Cynn, H.; Gorelli, F.; Toulemonde, P.; Machon, D.; Merlen, A.; San Miguel, A.; Amboage, M.; Aquilanti, G.; Mathon, O.; Pascarelli, S.; Itie, J.P.; Mcmillan, P.F.; Trapananti, A.; Di Cicco, A.; Panfilis, S. de; Filipponi, A.; Kreisel, J.; Bouvier, P.; Dkhil, B.; Chaabane, B.; Rosner, H.; Koudela, D.; Schwarz, U.; Handestein, A.; Hanfland, M.; Opahle, I.; Koepernik, K.; Kuzmin, M.; Mueller, K.H.; Mydosh, J.; Richter, M.; Hejny, C.; Falconi, S.; Lundegaard, L.F.; Mcmahon, M.I; Loa, I.; Syassen, K.; Wang, X.; Roth, H.; Lorenz, T.; Farber Daniel, I.; Antonangeli Daniele, I.; Krisch, M.; Badro, J.; Fiquet, G.; Occelli, F.; Mao, W.L.; Mao, H.K.; Eng, P.; Kao, C.C.; Shu, J.F.; Hemley, R.J.; Tse, J.S.; Yao, Y.; Deen, P.P.; Paolasini, I.; Braithwaite, D.; Kernavanois, N.; Lapertot, G.; Rupprecht, K.; Leupold, O.; Ponkratz, U.; Wortmann, G.; Beraud, A.; Krisch, M.; Farber, D.; Antonangeli, D.; Aracne, C.; Zarestky, J.L.; Mcqueeney, R.; Mathon, O.; Baudelet, F.; Decremps, F.; Itie, J.P.; Nataf, I.; Pascarelli, S.; Polian, A

    2006-07-01

    The workshop is dedicated to recent advances on science at high pressure at third generation synchrotron sources. A variety of experiments using synchrotron radiation techniques including X-ray diffraction, EXAFS (extended X-ray absorption fine structure), inelastic X-ray scattering, Compton scattering and Moessbauer spectroscopy of crystalline, liquid or amorphous samples, are reported. This document gathers the abstracts of the presentations.

  6. Role of routine abdominal ultrasonography in intensified tuberculosis case finding algorithms at HIV clinics in high TB burden settings.

    Science.gov (United States)

    Spalgais, Sonam; Agarwal, Upasna; Sarin, Rohit; Chauhan, Devesh; Yadav, Anita; Jaiswal, Anand

    2017-05-18

    High proportion of TB in people living with HIV (PLHIV) is undiagnosed. Due to this active TB case finding is recommended for HIV clinics in high TB burden countries. Presently sputum examination and chest radiography are frontline tests recommended for HIV infected TB presumptives. Abdominal TB which occurs frequently in PLHIV may be missed even by existing programmatic intensified case finding protocols. This study evaluated the routine use of ultrasonography (USG) for active case finding of abdominal TB in HIV clinics. Retrospective analysis of eight years' data from an HIV Clinic in a TB hospital in India. Patients underwent chest x-ray, sputum examination, USG abdomen and routine blood tests at entry to HIV care. Case forms were scrutinized for diagnosis of TB, USG findings and CD4 cell counts. Abdominal TB was classified as probable or possible TB. Probable TB was based on presence of two major USG (abdomen) findings suggestive of active TB, or one major USG finding with at least two minor USG findings or at least two symptoms, or any USG finding with microbiologically confirmed active TB at another site. Possible TB was based on the presence of one major USG finding, or the presence of two minor USG findings with at least two symptoms. Bacteriological confirmation was not obtained. Eight hundred and eighty-nine people PLHIV underwent a baseline USG abdomen. One hundred and thirteen of 340 cases already diagnosed with TB and 87 of the 91 newly diagnosed with TB at time of HIV clinic registration had abdominal TB. Non-abdominal symptoms like weight loss, fever and cough were seen in 53% and 22% cases had no symptoms at all. Enlarged abdominal lymph nodes with central caseation, ascitis, splenic microabsesses, bowel thickening and hepatosplenomegaly were the USG findings in these cases. Abdominal TB is a frequent TB site in PLHIV presenting with non-abdominal symptoms. It can be easily detected on basis of features seen on a simple abdominal ultrasound

  7. Foaming Glass Using High Pressure Sintering

    DEFF Research Database (Denmark)

    Østergaard, Martin Bonderup; Petersen, Rasmus Rosenlund; König, Jakob

    Foam glass is a high added value product which contributes to waste recycling and energy efficiency through heat insulation. The foaming can be initiated by a chemical or physical process. Chemical foaming with aid of a foaming agent is the dominant industrial process. Physical foaming has two...... microscope above maximum foaming temperature gives a suitable foaming temperature for the remaining samples. We show that the foaming kinetics depend on the type of gas and the pressure. A critical pressure of around 20 MPa is found to give the largest expansion for all gasses. Samples are obtained with 100...

  8. Vascular surgical society of great britain and ireland: immunoglobulin A antibodies against chlamydia pneumoniae are associated with expansion of small abdominal aortic aneurysms and declining ankle blood pressure

    DEFF Research Database (Denmark)

    Lindholt, Jes S.; Vammen; Henneberg

    1999-01-01

    or greater, were significant independent predictors of AAA expansion adjusted for age, smoking, initial AAA size, steroid treatment, diastolic blood pressure, pulmonary function and other plasma factors. The ankle blood pressure index (ABI) of the IgA-seropositive men decreased 11 per cent, while the ABI...... decreased by 5 per cent among IgA-seronegative men (P blood pressure, initial brachial systolic or diastolic blood pressure, but disappeared after adjusting for low-density lipoprotein (LDL) levels......BACKGROUND: The potential correlation between chronic infection with Chlamydia pneumoniae and the progression of small abdominal aortic aneurysms (AAAs) and lower limb atherosclerosis was studied. METHODS: Mass screening for AAA was carried out in outdoor clinics at all hospitals in the county...

  9. (Ultra high pressure homogenization for continuous high pressure sterilization of pumpable foods - a review

    Directory of Open Access Journals (Sweden)

    Erika eGeorget

    2014-08-01

    Full Text Available Bacterial spores have a strong resistance to both chemical and physical hurdles and create a risk for food industry which has been tackled by applying high thermal intensity treatments to sterilize food. These strong thermal treatments lead to reduction of the organoleptic and nutritional properties of food and alternative are actively searched for. Innovative hurdles offer an alternative to inactivate bacterial spores. In particular, recent technological developments have enabled a new generation of high pressure homogenizer working at pressures up to 400 MPa and thus opening new opportunities for high pressure sterilization of foods. In this short review, we summarize the work conducted on (ultra-high pressure homogenization (UHPH to inactivate endospores in model and food systems. Specific attention is given to process parameters (pressure, inlet and valve temperatures. This review gathers the current state of the art and underlines the potential of UHPH sterilization of pumpable foods while highlighting the needs for future work.

  10. Zeeman Effect in Ruby at High Pressures

    Science.gov (United States)

    Dan, Ioana

    2012-02-01

    We have developed a versatile fiber-coupled system for magneto-optical spectroscopy measurements at high pressure. The system is based on a miniature Cu-alloy Diamond Anvil Cell (from D'Anvils, Ltd) fitted with a custom-designed He gas-actuated membrane for in-situ pressure control, and coupled with a He transfer cryostat incorporating a superconducting magnet (from Quantum Designs). This system allows optical measurements (Raman, photoluminescence, reflectivity) within wide ranges of pressures (up to 100GPa), temperatures (4.2-300K) and magnetic fields (0-9T). We employ this system to examine the effect of pressure and non-hydrostatic stress on the Zeeman split d-d transitions of Cr^3+ in ruby (Al2O3: Cr^3+). We determine the effect of pressure and non-hydrostaticity on the trigonal crystal field in this material, and discuss the use of the Zeman-split ruby fluorescence as a possible probe for deviatoric stresses in diamond anvil cell experiments.

  11. High Pressure Behavior of FeOOH

    Science.gov (United States)

    Reagan, M. M.; Gleason, A. E.; Mao, W. L.

    2013-12-01

    Understanding the stability and properties of simple hydroxides at high pressures and temperatures offers an important first step toward quantifying more complex hydrogen-bearing compounds relevant to the Earth's interior. We focus on iron-oxy-hydroxides because they may be an important Fe and water bearing component in the deep Earth. Goethite (α-FeOOH) transforms to a high-pressure phase, ɛ-FeOOH, which is isostructural with δ-AlOOH, a material which may transport hydrogen to the core-mantle boundary. Here we present XES spectroscopy data of powder samples of synthesized alpha-FeOOH, beta-FeOOH and gamma-FeOOH monitoring their electronic spin transition. The samples was loaded into a Beryllium gasket, where a 50 micron hole served as the sample chamber with 300 micron culet diamond paired with a beveled 150 micron diamond in a diamond-anvil cell (DAC) without a pressure transmitting medium. Pressure was determined using ruby fluorescence (Mao et al. 1978). Using the incident X-ray energy centered at 11.3 KeV from the Advanced Photon Source, beam line HPCAT 16-ID-D, we measured Fe K-β 13 emission to pressures greater than 73 GPa. For alpha-FeOOH, we saw a clear shift in the main peak to lower energy, and an increasingly diminishing K beta prime peak intensity, indicating the sample was undergoing an electronic spin transition. The K beta prime peak completely disappeared at a pressure greater than 73 GPa. Beta-FeOOH showed no evidence of the beginnings of a spin transition, while gamma- FeOOH underwent an incomplete transition.

  12. Yoga Called Good Medicine for High Blood Pressure

    Science.gov (United States)

    ... fullstory_162446.html Yoga Called Good Medicine for High Blood Pressure People who added this practice to a healthy ... elevated blood pressure] are likely to develop hypertension [high blood pressure] unless they improve their lifestyle," said study author ...

  13. Is sodium a superconductor under high pressure?

    Science.gov (United States)

    Tutchton, Roxanne; Chen, Xiaojia; Wu, Zhigang

    2017-01-07

    Superconductivity has been predicted or measured for most alkali metals under high pressure, but the computed critical temperature (Tc) of sodium (Na) at the face-centered cubic (fcc) phase is vanishingly low. Here we report a thorough, first-principles investigation of superconductivity in Na under pressures up to 260 GPa, where the metal-to-insulator transition occurs. Linear-response calculations and density functional perturbation theory were employed to evaluate phonon distributions and the electron-phonon coupling for bcc, fcc, cI16, and tI19 Na. Our results indicate that the maximum electron-phonon coupling parameter, λ, is 0.5 for the cI16 phase, corresponding to a theoretical peak in the critical temperature at Tc≈1.2 K. When pressure decreases or increases from 130 GPa, Tc drops quickly. This is mainly due to the lack of p-d hybridization in Na even at 260 GPa. Since current methods based on the Eliashberg and McMillian formalisms tend to overestimate the Tc (especially the peak values) of alkali metals, we conclude that under high pressure-before the metal-to-insulator transition at 260 GPa-superconductivity in Na is very weak, if it is measurable at all.

  14. Picosecond High Pressure Gas Switch experiment

    Energy Technology Data Exchange (ETDEWEB)

    Cravey, W.R.; Freytag, E.K.; Goerz, D.A.; Poulsen, P.; Pincosy, P.A.

    1993-08-01

    A high Pressure Gas Switch has been developed and tested at LLNL. Risetimes on the order of 200 picoseconds have been observed at 1 kHz prf and 1 atmosphere pressures. Calculations show that switching closure times on the order of tens of picoseconds can be achieved at higher pressures and electric fields. A voltage hold-off of 1 MV/cm has been measured at 10 atmospheres and several MV/cm appears possible with the HPGS. With such high electric field levels, energy storage of tens of Joules in a reasonably sized package is achievable. Initial HPGS performance has been characterized using the WASP pulse generator at LLNL. A detailed description of the switch used for initial testing is given. Switch recovery times of 1-ms have been measured at 1 atmosphere. Data on the switching uniformity, voltage hold-off recovery, and pulse repeatability, is presented. In addition, a physics switch model is described and results are compared with experimental data. Modifications made to the WASP HV pulser in order to drive the HPGS will also be discussed. Recovery times of less than 1 ms were recorded without gas flow in the switch chambers. Low pressure synthetic air was used as the switch dielectric. Longer recovery times were required when it was necessary to over-voltage the switch.

  15. Strain engineered pyrochlore at high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Rittman, Dylan R.; Turner, Katlyn M.; Park, Sulgiye; Fuentes, Antonio F.; Park, Changyong; Ewing, Rodney C.; Mao, Wendy L.

    2017-05-22

    Strain engineering is a promising method for next-generation materials processing techniques. Here, we use mechanical milling and annealing followed by compression in diamond anvil cell to tailor the intrinsic and extrinsic strain in pyrochlore, Dy2Ti2O7 and Dy2Zr2O7. Raman spectroscopy, X-ray pair distribution function analysis, and X-ray diffraction were used to characterize atomic order over short-, medium-, and long-range spatial scales, respectively, under ambient conditions. Raman spectroscopy and X-ray diffraction were further employed to interrogate the material in situ at high pressure. High-pressure behavior is found to depend on the species and concentration of defects in the sample at ambient conditions. Overall, we show that defects can be engineered to lower the phase transformation onset pressure by ~50% in the ordered pyrochlore Dy2Zr2O7, and lower the phase transformation completion pressure by ~20% in the disordered pyrochlore Dy2Zr2O7. These improvements are achieved without significantly sacrificing mechanical integrity, as characterized by bulk modulus.

  16. High-sensitive cardiac troponin T measurements in prediction of non-cardiac complications after major abdominal surgery

    NARCIS (Netherlands)

    Noordzij, P. G.; van Geffen, O.; Dijkstra, I. M.; Boerma, D.; Meinders, A. J.; Rettig, T. C D; Eefting, F. D.; van Loon, D.; van de Garde, E. M W; van Dongen, E. P A

    2015-01-01

    BACKGROUND: Postoperative non-cardiac complication rates are as high as 11-28% after high-risk abdominal procedures. Emerging evidence indicates that postoperative cardiac troponin T elevations are associated with adverse outcome in non-cardiac surgery. The aim of this study was to determine the rel

  17. High frequency of beta-catenin heterozygous mutations in extra-abdominal fibromatosis: a potential molecular tool for disease management.

    Science.gov (United States)

    Dômont, J; Salas, S; Lacroix, L; Brouste, V; Saulnier, P; Terrier, P; Ranchère, D; Neuville, A; Leroux, A; Guillou, L; Sciot, R; Collin, F; Dufresne, A; Blay, J-Y; Le Cesne, A; Coindre, J-M; Bonvalot, S; Bénard, J

    2010-03-16

    Fibromatosis comprises distinct clinical entities, including sporadic extra-abdominal fibromatosis, which have a high tendency for recurrence, even after adequate resection. There are no known molecular biomarkers of local recurrence. We searched for beta-catenin mutations in a European multicentre series of fibromatosis tumours to relate beta-catenin mutational status to disease outcome. Direct sequencing of exon 3 beta-catenin gene was performed for 155 frozen fibromatosis tissues from all topographies. Correlation of outcome with mutation rate and type was performed on the extra-abdominal fibromatosis group (101 patients). Mutations of beta-catenin were detected in 83% of all cases. Among 101 extra-abdominal fibromatosis, similar mutation rates (87%) were observed, namely T41A (39.5%), S45P (9%), S45F (36.5%), and deletion (2%). None of the clinico-pathological parameters were found to be significantly associated with beta-catenin mutational status. With a median follow-up of 62 months, 51 patients relapsed. Five-year recurrence-free survival was significantly worse in beta-catenin-mutated tumours regardless of a specific genotype, compared with wild-type tumours (49 vs 75%, respectively, P=0.02). A high frequency (87%) of beta-catenin mutation hallmarks extra-abdominal fibromatosis from a large multicentric retrospective study. Moreover, wild-type beta-catenin seems to be an interesting prognostic marker that might be useful in the therapeutic management of extra-abdominal fibromatosis.

  18. Abdominal Obesity and their association with Total Body: Fat Distribution and Composition. Case of Algerian Teenager Male high school students

    Directory of Open Access Journals (Sweden)

    Mohammed Zerf

    2017-06-01

    Full Text Available Purpose: Our aim attempted to esteem the impact of abdominal fat on body fat distribution or composition related to total body fat as recommended weight loss among High School Students. Material: For the proposed, 100 male students from the Algerian high school Education Sector's mandate Sidi Bel Abbes, participate in the present study. Their average age 16±1.52 years, distributed into homogeneous groups, according to their body fat percent categories. Examined by saving tests (Body Fat Percentage (BFP - Abdominal circumference (WC - Body mass index (BMI. Results: Based on the test data and the analysis statistics applied, we confirm: a Abdominal obesity is excess body gain correlate with total fat BMI. It highly affected body composition reported as additional fat for overweight in compare with acceptable according to Ideal BFP categories. b Abdominal obesity is an amount deep fat correlates to total BFP. It higher influenced the distribution of total body fat reported as additional excess fat among overweight category compared to the acceptable group. c Waist circumference (WC is the leading marker of abdominal fat deposits located in the central region of the body. While the combination of body mass index (BMI and waist circumference (WC, reflects the combined effects of body build (fat or fatness in individuals at higher risk of excessive body fat. Conclusions: founded on the differences acquired by the research team. We highlight that abdominal obesity is strongly connected to larger WC relate to total body gain located as excess inordinate fatness BMI or fat distribution BFP among our overall sample. Evidence, which guides us to recommend our adolescent students to intensification their hours of sports practice, in order to avoid the consequences of abdominal obesity gain. Announced in the present study as excess abdominal adiposity more metabolically active. Requiring the control of body weight loss (BFP or BMI strongly correlates to

  19. Inspection technology for high pressure pipes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae H.; Lee, Jae C.; Eum, Heung S.; Choi, Yu R.; Moon, Soon S.; Jang, Jong H

    2000-02-01

    Various kinds of defects are likely to be occurred in the welds of high pressure pipes in nuclear power plants. Considering the recent accident of Zuruga nuclear power plant in Japan, reasonable policy is strongly requested for the high pressure pipe integrity. In this study, we developed the technologies to inspect pipe welds automatically. After development of scanning robot prototype in the first research year, we developed and implemented the algorithm of automatic tracking of the scanning robot along the weld line of the pipes. We use laser slit beam on weld area and capture the image using digital camera. Through processing of the captures image, we finally determine the weld line automatically. In addition, we investigated a new technology on micro systems for developing micro scanning robotic inspection of the pipe welds. The technology developed in this study is being transferred to the industry. (author)

  20. High Mobility Group Box-1 Protein and Outcomes in Critically Ill Surgical Patients Requiring Open Abdominal Management

    Directory of Open Access Journals (Sweden)

    Michelle S. Malig

    2017-01-01

    Full Text Available Background. Previous studies assessing various cytokines in the critically ill/injured have been uninformative in terms of translating to clinical care management. Animal abdominal sepsis work suggests that enhanced intraperitoneal (IP clearance of Damage-Associated Molecular Patterns (DAMPs improves outcome. Thus measuring the responses of DAMPs offers alternate potential insights and a representative DAMP, High Mobility Group Box-1 protein (HMGB-1, was considered. While IP biomediators are being recognized in critical illness/trauma, HMGB-1 behaviour has not been examined in open abdomen (OA management. Methods. A modified protocol for HMGB-1 detection was used to examine plasma/IP fluid samples from 44 critically ill/injured OA patients enrolled in a randomized controlled trial comparing two negative pressure peritoneal therapies (NPPT: Active NPPT (ANPPT and Barker’s Vacuum Pack NPPT (BVP. Samples were collected and analyzed at the time of laparotomy and at 24 and 48 hours after. Results. There were no statistically significant differences in survivor versus nonsurvivor HMGB-1 plasma or IP concentrations at baseline, 24 hours, or 48 hours. However, plasma HMGB-1 levels tended to increase continuously in the BVP cohort. Conclusions. HMGB-1 appeared to behave differently between NPPT cohorts. Further studies are needed to elucidate the relationship of HMGB-1 and outcomes in septic/injured patients.

  1. High-pressure investigations of Earth's interior

    Science.gov (United States)

    Jackson, Jennifer

    2007-03-01

    In the first half of the talk, the electronic structure of iron in ferromagnesium silicate perovskite will be discussed. Knowledge of iron valences and spin states in silicate perovskite is relevant to our understanding of the physical and chemical properties of Earth's lower mantle such as transport properties, mechanical behavior, and element partitioning. In this study, we have measured the electronic structure of the iron component of an aluminous Fe-bearing silicate perovskite sample, (Mg0.88Fe0.09)(Si0.94Al0.10)O3, close to a pyrolite composition, using synchrotron M"ossbauer spectroscopy (SMS) and laser heated diamond anvil cells at high-pressure and temperatures at beamline 3-ID of the Advanced Photon Source. Evaluation of the spectra provided the isomer shift and the quadrupole splitting of the iron component in silicate perovskite, which gives information on valence and spin states under lower mantle conditions. In the second half of the talk, experiments on the melting curve of iron at high-pressures will be presented. Seismological observations indicate that Earth's iron-dominated core consists of a solid inner region surrounded by a liquid outer core. Previously, melting studies of iron metal at high-pressures and temperatures were performed by shock-compression, resistive- and laser-heating in diamond anvil cells using visual observations or synchrotron x-ray diffraction and theoretical methods. However, the melting curve of iron is still controversial. Here, we will present a new method of detecting the solid-liquid phase boundary of iron at high-pressure using ^57Fe SMS. The characteristic SMS time signature is observed by fast detectors and vanishes suddenly when melting occurs. This process is described by the Lamb-M"ossbauer factor f = exp(-k^2), where k is the wave number of the resonant x-rays and is the mean-square displacement of the iron atoms.

  2. Modeling High Pressure Micro Hollow Cathode Discharges

    Science.gov (United States)

    2007-11-02

    cathode discharge excimer lamps , Phys. Plasmas 7, 286 (2000). [3] RH Stark and KH Schoenbach, Direct high pressure glow discharges, J. Appl. Phys...temperature profiles in argon glow discharges, J. Appl. Phys. 88, 2234 (2000) [8] M. Moselhy, W. Shi, R. Stark, A flat glow discharge excimer radiation...MHCD acts as a plasma cathode for a third electrode (anode). Some experimental results in this geometry are available for argon and for air from the

  3. High Pressure Multicomponent Adsorption in Porous Media

    DEFF Research Database (Denmark)

    Shapiro, Alexander; Stenby, Erling Halfdan

    1999-01-01

    We analyse adsorption of a multicomponent mixture at high pressure on the basis of the potential theory of adsorption. The adsorbate is considered as a segregated mixture in the external field produced by a solid adsorbent. we derive an analytical equation for the thickness of a multicomponent film...... close to a dew point. This equation (asymptotic adsorption equation, AAE) is a first order approximation with regard to the distance from a phase envelope....

  4. Structures of xenon oxides at high pressures

    Science.gov (United States)

    Worth, Nicholas; Pickard, Chris; Needs, Richard; Dewaele, Agnes; Loubeyre, Paul; Mezouar, Mohamed

    2014-03-01

    For many years, it was believed that noble gases such as xenon were entirely inert. It was only in 1962 that Bartlett first synthesized a compound of xenon. Since then, a number of other xenon compounds, including oxides, have been synthesized. Xenon oxides are unstable under ambient conditions but have been predicted to stabilize under high pressure. Here we present the results of a combined theoretical and experimental study of xenon oxides at pressures of 80-100 GPa. We have synthesized new xenon oxides at these pressures and they have been characterized with X-ray diffraction and Raman spectroscopy. Calculations were performed with a density-functional theory framework. We have used the ab-initio random structure searching (AIRSS) method together with a data-mining technique to determine the stable compounds in the xenon-oxygen system in this pressure range. We have calculated structural and optical properties of these phases, and a good match between theoretical and experimental results has been obtained. Funding for computational research provided by the engineering and physical sciences research council (EPSRC; UK). Computing resources provided by Cambridge HPC and HECToR. X-ray diffraction experiments performed at ESRF.

  5. 7 CFR 58.219 - High pressure pumps and lines.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false High pressure pumps and lines. 58.219 Section 58.219....219 High pressure pumps and lines. High pressure lines may be cleaned-in-place and shall be of such construction that dead ends, valves and the high pressure pumps can be disassembled for hand cleaning. The...

  6. Prediction of Production Power for High-pressure Hydrogen by High-pressure Water Electrolysis

    Science.gov (United States)

    Kyakuno, Takahiro; Hattori, Kikuo; Ito, Kohei; Onda, Kazuo

    Recently the high attention for fuel cell electric vehicle (FCEV) is pushing to construct the hydrogen supplying station for FCEV in the world. The hydrogen pressure supplied at the current test station is intended to be high for increasing the FCEV’s driving distance. The water electrolysis can produce cleanly the hydrogen by utilizing the electricity from renewable energy without emitting CO2 to atmosphere, when it is compared to be the popular reforming process of fossil fuel in the industry. The power required for the high-pressure water electrolysis, where water is pumped up to high-pressure, may be smaller than the power for the atmospheric water electrolysis, where the produced atmospheric hydrogen is pumped up by compressor, since the compression power for water is much smaller than that for hydrogen gas. In this study the ideal water electrolysis voltage up to 70MPa and 523K is estimated referring to both the results by LeRoy et al up to 10MPa and 523K, and to the latest steam table. By using this high-pressure water electrolysis voltage, the power required for high-pressure hydrogen produced by the high-pressure water electrolysis method is estimated to be about 5% smaller than that by the atmospheric water electrolysis method, by assuming the compressor and pump efficiency of 50%.

  7. Operating mode of high pressure straws with high spatial resolution

    CERN Document Server

    Davkov, K I; Peshekhonov, V D; Cholakov, V D

    2013-01-01

    The article presents results of studying the operating mode of thin-walled drift tubes (straws) at flushing it with a high-pressure gas mixture, which allowed obtaining extremely high spatial resolution for straw detectors. The results of studying the radiation ageing of straws operating in this mode are also described.

  8. Modeling Study of High Pressure and High Temperature Reservoir Fluids

    DEFF Research Database (Denmark)

    Varzandeh, Farhad

    to 250 °C and 2400 bar, in the deep petroleum reservoirs. Furthermore, many of these deep reservoirs are found offshore, including the North Sea and the Gulf of Mexico, making the development even more risky. On the other hand, development of these high pressure high temperature (HPHT) fields can...

  9. Pulse Radiolysis at High Temperatures and High Pressures

    DEFF Research Database (Denmark)

    Christensen, H.; Sehested, Knud

    1981-01-01

    A set-up enabling pulse radiolysis measurements at high temperatures (up to 320°C) and high pressures (up to 140 bar) has been constructed in collaboration between Risö National Laboratory and Studsvik Energiteknik. The cell has been used for experiments with aqueous solutions with the purpose...

  10. Dietary spermidine for lowering high blood pressure

    Science.gov (United States)

    Zimmermann, Andreas; Schroeder, Sabrina; Pendl, Tobias; Harger, Alexandra; Stekovic, Slaven; Schipke, Julia; Magnes, Christoph; Schmidt, Albrecht; Ruckenstuhl, Christoph; Dammbrueck, Christopher; Gross, Angelina S; Herbst, Viktoria; Carmona-Gutierrez, Didac; Pietrocola, Federico; Pieber, Thomas R; Sigrist, Stephan J; Linke, Wolfgang A; Mühlfeld, Christian; Sadoshima, Junichi; Dengjel, Joern; Kiechl, Stefan; Kroemer, Guido; Sedej, Simon; Madeo, Frank

    2017-01-01

    Loss of cardiac macroautophagy/autophagy impairs heart function, and evidence accumulates that an increased autophagic flux may protect against cardiovascular disease. We therefore tested the protective capacity of the natural autophagy inducer spermidine in animal models of aging and hypertension, which both represent major risk factors for the development of cardiovascular disease. Dietary spermidine elicits cardioprotective effects in aged mice through enhancing cardiac autophagy and mitophagy. In salt-sensitive rats, spermidine supplementation also delays the development of hypertensive heart disease, coinciding with reduced arterial blood pressure. The high blood pressure-lowering effect likely results from improved global arginine bioavailability and protection from hypertension-associated renal damage. The polyamine spermidine is naturally present in human diets, though to a varying amount depending on food type and preparation. In humans, high dietary spermidine intake correlates with reduced blood pressure and decreased risk of cardiovascular disease and related death. Altogether, spermidine represents a cardio- and vascular-protective autophagy inducer that can be readily integrated in common diets. PMID:28118075

  11. Music as a nursing intervention: effects of music listening on blood pressure, heart rate, and respiratory rate in abdominal surgery patients.

    Science.gov (United States)

    Vaajoki, Anne; Kankkunen, Päivi; Pietilä, Anna-Maija; Vehviläinen-Julkunen, Katri

    2011-12-01

    Contradictory results have been presented on how music listening affects patients' blood pressure, heart rate, and respiratory rate. The aim of the present study was to evaluate the effects of music listening on blood pressure, heart rate, and respiratory rate on operation day, and on the first, second, and third postoperative days in abdominal surgery patients. Using a quasi-experimental pretest-post-test design, 168 abdominal surgery patients were assigned every second week to the music group (n=83) or to the control group (n=85) for 25 months. In the music group, the respiratory rate was significantly lower after intervention on both the first and second postoperative days compared with the control group. A significant reduction in systolic blood pressure was demonstrated in the group that received music compared with the control group on both the first and second postoperative days. Evaluation of the long-term effects of music on physiological factors showed that the respiratory rate in the music group was significantly lower compared with the control group. Nurses should offer music listening to surgery patients because of its potential benefit.

  12. Comparison of Muscle Activities Using a Pressure Biofeedback Unit during Abdominal Muscle Training Performed by Normal Adults in the Standing and Supine Positions.

    Science.gov (United States)

    Jung, Da-Eun; Kim, Kyoung; Lee, Su-Kyoung

    2014-02-01

    [Purpose] The purpose of this study was to assess the effects of draw-in exercise on abdominal muscle activity in the standing and supine positions. [Methods] Twenty healthy women participated in this study. The subjects were required to complete two draw-in exercises (standing and supine positions) using a biofeedback pressure unit. The root mean square (RMS) values of the EMG data were expressed as a percentage of the resting contraction. The data were analyzed using the independent t-test. [Results] According to the changes in the activities of the abdominal muscles, the draw-in exercise in the standing position produced the most significant increase in the activities of the rectus abdominis, the transverse abdominis, the internal oblique, and the external oblique muscles. [Conclusion] The activities of the trunk stability muscles (rectus abdominis, transverse abdominis, internal oblique, and external oblique) increased more in the standing than in the supine position, enabling the subjects to overcome gravity. Therefore, to strengthen the activation of the abdominal muscles, a standing position seems to be more effective than a supine position for draw-in exercises.

  13. High stored energy of metallic glasses induced by high pressure

    Science.gov (United States)

    Wang, C.; Yang, Z. Z.; Ma, T.; Sun, Y. T.; Yin, Y. Y.; Gong, Y.; Gu, L.; Wen, P.; Zhu, P. W.; Long, Y. W.; Yu, X. H.; Jin, C. Q.; Wang, W. H.; Bai, H. Y.

    2017-03-01

    Modulating energy states of metallic glasses (MGs) is significant in understanding the nature of glasses and controlling their properties. In this study, we show that high stored energy can be achieved and preserved in bulk MGs by high pressure (HP) annealing, which is a controllable method to continuously alter the energy states of MGs. Contrary to the decrease in enthalpy by conventional annealing at ambient pressure, high stored energy can occur and be enhanced by increasing both annealing temperature and pressure. By using double aberration corrected scanning transmission electron microscopy, it is revealed that the preserved high energy, which is attributed to the coupling effect of high pressure and high temperature, originates from the microstructural change that involves "negative flow units" with a higher atomic packing density compared to that of the elastic matrix of MGs. The results demonstrate that HP-annealing is an effective way to activate MGs into higher energy states, and it may assist in understanding the microstructural origin of high energy states in MGs.

  14. High pressure study of high-temperature superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Souliou, Sofia-Michaela

    2014-09-29

    The current thesis studies experimentally the effect of high external pressure on high-T{sub c} superconductors. The structure and lattice dynamics of several members of the high-T{sub c} cuprate and Fe-based superconductors families were investigated by means of Raman spectroscopy and X-ray diffraction under well-controlled, hydrostatic high pressure and low temperature conditions. The lattice dynamics of the high-T{sub c} superconductor YBa{sub 2}Cu{sub 3}O{sub 6+x} have been investigated systematically by Raman spectroscopy as a function of doping (x = 0.95, 0.75, 0.60, 0.55, and 0.45) and external pressure. Under ambient pressure conditions, in addition to the Raman modes expected from group theory, we observe new Raman active phonons upon cooling the underdoped samples, at temperatures well above the superconducting transition temperature. The doping dependence and the onset temperatures of the new Raman features suggest that they are associated with the incommensurate charge density wave (CDW) state recently discovered in underdoped cuprates using synchrotron X-ray scattering techniques. Under high pressure conditions (from 2 to 12 GPa), our Raman measurements on highly ordered underdoped YBa{sub 2}Cu{sub 3}O{sub 6.55} samples do not show any of the new Raman phonons seen at ambient pressure. High pressure and low temperature Raman measurements have been performed on the underdoped superconductor YBa{sub 2}Cu{sub 4}O{sub 8}. A clear renormalization of some of the Raman phonons is seen below T{sub c} as a result of the changes in the phonon self-energy upon the opening of the superconducting gap, with the most prominent one being that of the B{sub 1g}-like buckling phonon mode. The amplitude of this renormalization strongly increases with pressure, resembling the effect of hole doping in YBa{sub 2}Cu{sub 3}O{sub 6+x}. At ∝ 10 GPa, the system undergoes a reversible pressure-induced structural phase transition to a non-centrosymmmetric structure (space group

  15. High-normal blood pressure and the risk of cardiovascular disease.

    Science.gov (United States)

    Kokubo, Yoshihiro; Kamide, Kei

    2009-08-01

    The guidelines of the Joint National Committee 7 from the USA on hypertension have unified the normal and high-normal blood pressure categories into a single entity termed ;prehypertension'. In contrast, The European Guidelines for the management of hypertension in 2007 considered ;prehypertensive' to be divided into normal and high-normal blood pressure. These patients with high-normal blood pressure or prehypertension might progress to hypertension over time. Previous studies have shown that high-normal blood pressure is a risk factor for cardiovascular disease (CVD) in Western countries and Japan. The combination of high-normal blood pressure and other cardiovascular risk factors increases the risks of CVD. Recently, metabolic syndrome has also been shown to be a risk factor for CVD. In Japan, the association between metabolic syndrome and CVD was also found to be significant. The risks for CVD incidence were similar among participants who had the same number of components, regardless of the presence of abdominal obesity. In the Japanese guidelines for the management of hypertension published in 2009, patients are considered to be in a high-risk group if they have diabetes, chronic kidney disease, 3 or more risk factors, target organ damage or CVD, even if they have only high-normal blood pressure, and appropriate antihypertensive therapy should be initiated.

  16. Menopause and High Blood Pressure: What's the Connection?

    Science.gov (United States)

    ... blood pressure (hypertension) Is there a connection between menopause and high blood pressure? Answers from Shannon K. ... Tommaso, M.D. Blood pressure generally increases after menopause. Some doctors think this increase suggests that hormonal ...

  17. High-pressure-high-temperature treatment of natural diamonds

    CERN Document Server

    Royen, J V

    2002-01-01

    The results are reported of high-pressure-high-temperature (HPHT) treatment experiments on natural diamonds of different origins and with different impurity contents. The diamonds are annealed in a temperature range up to 2000 sup o C at stabilizing pressures up to 7 GPa. The evolution is studied of different defects in the diamond crystal lattice. The influence of substitutional nitrogen atoms, plastic deformation and the combination of these is discussed. Diamonds are characterized at room and liquid nitrogen temperature using UV-visible spectrophotometry, Fourier transform infrared spectrophotometry and photoluminescence spectrometry. The economic implications of diamond HPHT treatments are discussed.

  18. LHDAC setup for high temperature and high pressure studies

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Nishant N., E-mail: nnpatel@barc.gov.in; Meenakshi, S., E-mail: nnpatel@barc.gov.in; Sharma, Surinder M., E-mail: nnpatel@barc.gov.in [High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Mumbai-400085 (India)

    2014-04-24

    A ytterbium fibre laser (λ = 1.07 μm) based laser heated diamond anvil cell (LHDAC) facility has been recently set up at HP and SRPD, BARC for simultaneous high temperature and high pressure investigation of material properties. Synthesis of GaN was carried out at pressure of ∼9 GPa and temperature of ∼1925 K in a Mao-Bell type diamond anvil cell (DAC) using the LHDAC facility. The retrieved sample has been characterized using our laboratory based micro Raman setup.

  19. 49 CFR 192.621 - Maximum allowable operating pressure: High-pressure distribution systems.

    Science.gov (United States)

    2010-10-01

    ... STANDARDS Operations § 192.621 Maximum allowable operating pressure: High-pressure distribution systems. (a) No person may operate a segment of a high pressure distribution system at a pressure that exceeds the... segment of a distribution system otherwise designed to operate at over 60 p.s.i. (414 kPa) gage,...

  20. Abdominal Compartment Syndrome: pathophysiology and definitions

    OpenAIRE

    Cheatham Michael L

    2009-01-01

    Abstract "Intra-abdominal hypertension", the presence of elevated intra-abdominal pressure, and "abdominal compartment syndrome", the development of pressure-induced organ-dysfunction and failure, have been increasingly recognized over the past decade as causes of significant morbidity and mortality among critically ill surgical and medical patients. Elevated intra-abdominal pressure can cause significant impairment of cardiac, pulmonary, renal, gastrointestinal, hepatic, and central nervous ...

  1. High-pressure structural properties of tetramethylsilane

    Science.gov (United States)

    Zhen-Xing, Qin; Xiao-Jia, Chen

    2016-02-01

    High-pressure structural properties of tetramethylsilane are investigated by synchrotron powder x-ray diffraction at pressures up to 31.1 GPa and room temperature. A phase with the space group of Pnma is found to appear at 4.2 GPa. Upon compression, the compound transforms to two following phases: the phase with space groups of P21/c at 9.9 GPa and the phase with P2/m at 18.2 GPa successively via a transitional phase. The unique structural character of P21/c supports the phase stability of tetramethylsilane without possible decomposition upon heavy compression. The appearance of the P2/m phase suggests the possible realization of metallization for this material at higher pressure. Project supported by the Cultivation Fund of the Key Scientific and Technical Innovation Project from Ministry of Education of China (Grant No. 708070), the Fundamental Research Funds for the Central Universities, South China University of Technology (Grant No. 2014ZZ0069), the National Natural Science Foundation of China (Grant No. 51502189), and the Doctoral Project of Taiyuan University of Science and Technology, China (Grant No. 20132010).

  2. High-pressure Raman study of Terephthalonitrile

    Science.gov (United States)

    Li, DongFei; Zhang, KeWei; Song, MingXing; Zhai, NaiCui; Sun, ChengLin; Li, HaiBo

    2017-02-01

    The in situ high-pressure Raman spectra of Terephthalonitrile (TPN) have been investigated from ambient to 12.6 GPa at room temperature. All the fundamental vibrational modes of TPN at ambient were assigned based on the first-principle calculations. A detailed Raman spectroscopy analysis revealed that TPN underwent a phase transition at 5.3 GPa. The frequencies of the TPN Raman peaks increase with increasing the pressure which can be attributed to the reduction in the interatomic distances and the escalation of effective force constants. The intensity of the C-C-C ring-out-plane deformation mode increases gradually as the frequency remains almost constant during the compression which can be explained by the existence of π-π interactions in TPN molecules. Additionally, the pressure-induced structural changes of TPN on the Fermi resonance between the C ≡ N out-of-plane vibration mode and the C - CN out-of-plane vibration mode have been analyzed.

  3. [Intraabdominal hypertension and abdominal compartment syndrome

    DEFF Research Database (Denmark)

    Sonne, M.; Hilligsø, Jens Georg

    2008-01-01

    Intraabdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are rare conditions with high mortality. IAH is an intraabdominal pressure (IAP) above 12 mmHg and ACS an IAP above 20 mmHg with evidence of organ dysfunction. IAP is measured indirectly via the bladder or stomach. Various...

  4. Recent progress in high-pressure studies on organic conductors

    Directory of Open Access Journals (Sweden)

    Syuma Yasuzuka and Keizo Murata

    2009-01-01

    Full Text Available Recent high-pressure studies of organic conductors and superconductors are reviewed. The discovery of the highest Tc superconductivity among organics under high pressure has triggered the further progress of the high-pressure research. Owing to this finding, various organic conductors with the strong electron correlation were investigated under high pressures. This review includes the pressure techniques using the cubic anvil apparatus, as well as high-pressure studies of the organic conductors up to 10 GPa showing extraordinary temperature and pressure dependent transport phenomena.

  5. High blood pressure in children and adolescents.

    Science.gov (United States)

    Riley, Margaret; Bluhm, Brian

    2012-04-01

    High blood pressure in children and adolescents is a growing health problem that is often overlooked by physicians. Normal blood pressure values for children and adolescents are based on age, sex, and height, and are available in standardized tables. Prehypertension is defined as a blood pressure in at least the 90th percentile, but less than the 95th percentile, for age, sex, and height, or a measurement of 120/80 mm Hg or greater. Hypertension is defined as blood pressure in the 95th percentile or greater. A secondary etiology of hypertension is much more likely in children than in adults, with renal parenchymal disease and renovascular disease being the most common. Overweight and obesity are strongly correlated with primary hypertension in children. A history and physical examination are needed for all children with newly diagnosed hypertension to help rule out underlying medical disorders. Children with hypertension should also be screened for other risk factors for cardiovascular disease, including diabetes mellitus and hyperlipidemia, and should be evaluated for target organ damage with a retinal examination and echocardiography. Hypertension in children is treated with lifestyle changes, including weight loss for those who are overweight or obese; a healthy, low-sodium diet; regular physical activity; and avoidance of tobacco and alcohol. Children with symptomatic hypertension, secondary hypertension, target organ damage, diabetes, or persistent hypertension despite nonpharmacologic measures should be treated with antihypertensive medications. Thiazide diuretics, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, beta blockers, and calcium channel blockers are safe, effective, and well tolerated in children.

  6. Conformable pressure vessel for high pressure gas storage

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, Kevin L.; Johnson, Kenneth I.; Lavender, Curt A.; Newhouse, Norman L.; Yeggy, Brian C.

    2016-01-12

    A non-cylindrical pressure vessel storage tank is disclosed. The storage tank includes an internal structure. The internal structure is coupled to at least one wall of the storage tank. The internal structure shapes and internally supports the storage tank. The pressure vessel storage tank has a conformability of about 0.8 to about 1.0. The internal structure can be, but is not limited to, a Schwarz-P structure, an egg-crate shaped structure, or carbon fiber ligament structure.

  7. "How to" incorporate dual-energy imaging into a high volume abdominal imaging practice.

    Science.gov (United States)

    Tamm, Eric P; Le, Ott; Liu, Xinming; Layman, Rick R; Cody, Dianna D; Bhosale, Priya R

    2017-03-01

    Dual-energy CT imaging has many potential uses in abdominal imaging. It also has unique requirements for protocol creation depending on the dual-energy scanning technique that is being utilized. It also generates several new types of images which can increase the complexity of image creation and image interpretation. The purpose of this article is to review, for rapid switching and dual-source dual-energy platforms, methods for creating dual-energy protocols, different approaches for efficiently creating dual-energy images, and an approach to navigating and using dual-energy images at the reading station all using the example of a pancreatic multiphasic protocol. It will also review the three most commonly used types of dual-energy images: "workhorse" 120kVp surrogate images (including blended polychromatic and 70 keV monochromatic), high contrast images (e.g., low energy monochromatic and iodine material decomposition images), and virtual unenhanced images. Recent developments, such as the ability to create automatically on the scanner the most common dual-energy images types, namely new "Mono+" images for the DSDECT (dual-source dual-energy CT) platform will also be addressed. Finally, an approach to image interpretation using automated "hanging protocols" will also be covered. Successful dual-energy implementation in a high volume practice requires careful attention to each of these steps of scanning, image creation, and image interpretation.

  8. Theory of high pressure hydrogen, made simple

    CERN Document Server

    Magdau, Ioan B; Ackland, Graeme J

    2015-01-01

    Phase I of hydrogen has several peculiarities. Despite having a close-packed crystal structure, it is less dense than either the low temperature Phase II or the liquid phase. At high pressure, it transforms into either phase III or IV, depending on the temperature. Moreover, spectroscopy suggests that the quantum rotor behaviour disappears with pressurisation, without any apparent phase transition. Here we present a simple thermodynamic model for this behaviour based on packing atoms and molecules and discuss the thermodynamics of the phase boundaries. We also report first principles molecular dynamics calculations for a more detailed look at the same phase transitions.

  9. CDC Vital Signs: High Blood Pressure and Cholesterol

    Science.gov (United States)

    ... the MMWR Science Clips High Blood Pressure and Cholesterol Out of Control Recommend on Facebook Tweet Share ... cdc.gov/GISCVH2/ High Blood Pressure and High Cholesterol Among US Adults SOURCES: National Health and Nutrition ...

  10. High Blood Pressure and Children: What Parents Need to Know

    Science.gov (United States)

    ... Lung, and Blood Institute Alternate Language URL Español High Blood Pressure and Children: What Parents Need to Know Page Content Children can have high blood pressure. Did you know that children could have high ...

  11. The added value of cardiac index and pulse pressure variation monitoring to mean arterial pressure-guided volume therapy in moderate-risk abdominal surgery (COGUIDE): a pragmatic multicentre randomised controlled trial.

    Science.gov (United States)

    Stens, J; Hering, J-P; van der Hoeven, C W P; Boom, A; Traast, H S; Garmers, L E; Loer, S A; Boer, C

    2017-09-01

    There is disagreement regarding the benefits of goal-directed therapy in moderate-risk abdominal surgery. Therefore, we tested the hypothesis that the addition of non-invasive cardiac index and pulse pressure variation monitoring to mean arterial pressure-based goal-directed therapy would reduce the incidence of postoperative complications in patients having moderate-risk abdominal surgery. In this pragmatic multicentre randomised controlled trial, we randomly allocated 244 patients by envelope drawing in a 1:1 fashion, stratified per centre. All patients had mean arterial pressure, cardiac index and pulse pressure variation measured continuously. In one group, healthcare professionals were blinded to cardiac index and pulse pressure variation values and were asked to guide haemodynamic therapy only based on mean arterial pressure (control group). In the second group, cardiac index and pulse pressure variation values were displayed and kept within target ranges following a pre-defined algorithm (CI-PPV group). The primary endpoint was the incidence of postoperative complications within 30 days. One hundred and seventy-five patients were eligible for final analysis. Overall complication rates were similar (42/94 (44.7%) vs. 38/81 (46.9%) in the control and CI-PPV groups, respectively; p = 0.95). The CI-PPV group had lower mean (SD) pulse pressure variation values (9.5 (2.0)% vs. 11.9 (4.6)%; p = 0.003) and higher mean (SD) cardiac indices (2.76 (0.62) l min(-1) .m(-2) vs. 2.53 (0.66) l min(-1) .m(-2) ; p = 0.004) than the control group. In moderate-risk abdominal surgery, we observed no additional value of cardiac index and pulse pressure variation-guided haemodynamic therapy to mean arterial pressure-guided volume therapy with regard to postoperative complications. © 2017 The Association of Anaesthetists of Great Britain and Ireland.

  12. Method transfer from high-pressure liquid chromatography to ultra-high-pressure liquid chromatography. II. Temperature and pressure effects.

    Science.gov (United States)

    Åsberg, Dennis; Samuelsson, Jörgen; Leśko, Marek; Cavazzini, Alberto; Kaczmarski, Krzysztof; Fornstedt, Torgny

    2015-07-03

    The importance of the generated temperature and pressure gradients in ultra-high-pressure liquid chromatography (UHPLC) are investigated and compared to high-pressure liquid chromatography (HPLC). The drug Omeprazole, together with three other model compounds (with different chemical characteristics, namely uncharged, positively and negatively charged) were used. Calculations of the complete temperature profile in the column at UHPLC conditions showed, in our experiments, a temperature difference between the inlet and outlet of 16 °C and a difference of 2 °C between the column center and the wall. Through van't Hoff plots, this information was used to single out the decrease in retention factor (k) solely due to the temperature gradient. The uncharged solute was least affected by temperature with a decrease in k of about 5% while for charged solutes the effect was more pronounced, with k decreases up to 14%. A pressure increase of 500 bar gave roughly 5% increase in k for the uncharged solute, while omeprazole and the other two charged solutes gave about 25, 20 and 15% increases in k, respectively. The stochastic model of chromatography was applied to estimate the dependence of the average number of adsorption/desorption events (n) and the average time spent by a molecule in the stationary phase (τs) on temperature and pressure on peak shape for the tailing, basic solute. Increasing the temperature yielded an increase in n and decrease in τs which resulted in less skew at high temperatures. With increasing pressure, the stochastic modeling gave interesting results for the basic solute showing that the skew of the peak increased with pressure. The conclusion is that pressure effects are more pronounced for both retention and peak shape than the temperature effects for the polar or charged compounds in our study.

  13. High blood pressure and visual sensitivity

    Science.gov (United States)

    Eisner, Alvin; Samples, John R.

    2003-09-01

    The study had two main purposes: (1) to determine whether the foveal visual sensitivities of people treated for high blood pressure (vascular hypertension) differ from the sensitivities of people who have not been diagnosed with high blood pressure and (2) to understand how visual adaptation is related to standard measures of systemic cardiovascular function. Two groups of middle-aged subjects-hypertensive and normotensive-were examined with a series of test/background stimulus combinations. All subjects met rigorous inclusion criteria for excellent ocular health. Although the visual sensitivities of the two subject groups overlapped extensively, the age-related rate of sensitivity loss was, for some measures, greater for the hypertensive subjects, possibly because of adaptation differences between the two groups. Overall, the degree of steady-state sensitivity loss resulting from an increase of background illuminance (for 580-nm backgrounds) was slightly less for the hypertensive subjects. Among normotensive subjects, the ability of a bright (3.8-log-td), long-wavelength (640-nm) adapting background to selectively suppress the flicker response of long-wavelength-sensitive (LWS) cones was related inversely to the ratio of mean arterial blood pressure to heart rate. The degree of selective suppression was also related to heart rate alone, and there was evidence that short-term changes of cardiovascular response were important. The results suggest that (1) vascular hypertension, or possibly its treatment, subtly affects visual function even in the absence of eye disease and (2) changes in blood flow affect retinal light-adaptation processes involved in the selective suppression of the flicker response from LWS cones caused by bright, long-wavelength backgrounds.

  14. High-pressure coal fuel processor development

    Energy Technology Data Exchange (ETDEWEB)

    Greenhalgh, M.L.

    1992-11-01

    The objective of Subtask 1.1 Engine Feasibility was to conduct research needed to establish the technical feasibility of ignition and stable combustion of directly injected, 3,000 psi, low-Btu gas with glow plug ignition assist at diesel engine compression ratios. This objective was accomplished by designing, fabricating, testing and analyzing the combustion performance of synthesized low-Btu coal gas in a single-cylinder test engine combustion rig located at the Caterpillar Technical Center engine lab in Mossville, Illinois. The objective of Subtask 1.2 Fuel Processor Feasibility was to conduct research needed to establish the technical feasibility of air-blown, fixed-bed, high-pressure coal fuel processing at up to 3,000 psi operating pressure, incorporating in-bed sulfur and particulate capture. This objective was accomplished by designing, fabricating, testing and analyzing the performance of bench-scale processors located at Coal Technology Corporation (subcontractor) facilities in Bristol, Virginia. These two subtasks were carried out at widely separated locations and will be discussed in separate sections of this report. They were, however, independent in that the composition of the synthetic coal gas used to fuel the combustion rig was adjusted to reflect the range of exit gas compositions being produced on the fuel processor rig. Two major conclusions resulted from this task. First, direct injected, ignition assisted Diesel cycle engine combustion systems can be suitably modified to efficiently utilize these low-Btu gas fuels. Second, high pressure gasification of selected run-of-the-mine coals in batch-loaded fuel processors is feasible. These two findings, taken together, significantly reduce the perceived technical risks associated with the further development of the proposed coal gas fueled Diesel cycle power plant concept.

  15. High Pressure Hydrogen from First Principles

    Science.gov (United States)

    Morales, M. A.

    2014-12-01

    Typical approximations employed in first-principles simulations of high-pressure hydrogen involve the neglect of nuclear quantum effects (NQE) and the approximate treatment of electronic exchange and correlation, typically through a density functional theory (DFT) formulation. In this talk I'll present a detailed analysis of the influence of these approximations on the phase diagram of high-pressure hydrogen, with the goal of identifying the predictive capabilities of current methods and, at the same time, making accurate predictions in this important regime. We use a path integral formulation combined with density functional theory, which allows us to incorporate NQEs in a direct and controllable way. In addition, we use state-of-the-art quantum Monte Carlo calculations to benchmark the accuracy of more approximate mean-field electronic structure calculations based on DFT, and we use GW and hybrid DFT to calculate the optical properties of the solid and liquid phases near metallization. We present accurate predictions of the metal-insulator transition on the solid, including structural and optical properties of the molecular phase. This work was supported by the U.S. Department of Energy at the Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344 and by LDRD Grant No. 13-LW-004.

  16. High pressure-resistant nonincendive emulsion explosive

    Science.gov (United States)

    Ruhe, Thomas C.; Rao, Pilaka P.

    1994-01-01

    An improved emulsion explosive composition including hollow microspheres/bulking agents having high density and high strength. The hollow microspheres/bulking agents have true particle densities of about 0.2 grams per cubic centimeter or greater and include glass, siliceous, ceramic and synthetic resin microspheres, expanded minerals, and mixtures thereof. The preferred weight percentage of hollow microspheres/bulking agents in the composition ranges from 3.0 to 10.0 A chlorinated paraffin oil, also present in the improved emulsion explosive composition, imparts a higher film strength to the oil phase in the emulsion. The emulsion is rendered nonincendive by the production of sodium chloride in situ via the decomposition of sodium nitrate, a chlorinated paraffin oil, and sodium perchlorate. The air-gap sensitivity is improved by the in situ formation of monomethylamine perchlorate from dissolved monomethylamine nitrate and sodium perchlorate. The emulsion explosive composition can withstand static pressures to 139 bars and dynamic pressure loads on the order of 567 bars.

  17. Stable magnesium peroxide at high pressure.

    Science.gov (United States)

    Lobanov, Sergey S; Zhu, Qiang; Holtgrewe, Nicholas; Prescher, Clemens; Prakapenka, Vitali B; Oganov, Artem R; Goncharov, Alexander F

    2015-09-01

    Rocky planets are thought to comprise compounds of Mg and O as these are among the most abundant elements, but knowledge of their stable phases may be incomplete. MgO is known to be remarkably stable to very high pressure and chemically inert under reduced condition of the Earth's lower mantle. However, in exoplanets oxygen may be a more abundant constituent. Here, using synchrotron x-ray diffraction in laser-heated diamond anvil cells, we show that MgO and oxygen react at pressures above 96 GPa and T = 2150 K with the formation of I4/mcm MgO2. Raman spectroscopy detects the presence of a peroxide ion (O2(2-)) in the synthesized material as well as in the recovered specimen. Likewise, energy-dispersive x-ray spectroscopy confirms that the recovered sample has higher oxygen content than pure MgO. Our finding suggests that MgO2 may be present together or instead of MgO in rocky mantles and rocky planetary cores under highly oxidized conditions.

  18. Stable magnesium peroxide at high pressure

    Science.gov (United States)

    Lobanov, Sergey S.; Zhu, Qiang; Holtgrewe, Nicholas; Prescher, Clemens; Prakapenka, Vitali B.; Oganov, Artem R.; Goncharov, Alexander F.

    2015-09-01

    Rocky planets are thought to comprise compounds of Mg and O as these are among the most abundant elements, but knowledge of their stable phases may be incomplete. MgO is known to be remarkably stable to very high pressure and chemically inert under reduced condition of the Earth’s lower mantle. However, in exoplanets oxygen may be a more abundant constituent. Here, using synchrotron x-ray diffraction in laser-heated diamond anvil cells, we show that MgO and oxygen react at pressures above 96 GPa and T = 2150 K with the formation of I4/mcm MgO2. Raman spectroscopy detects the presence of a peroxide ion (O22-) in the synthesized material as well as in the recovered specimen. Likewise, energy-dispersive x-ray spectroscopy confirms that the recovered sample has higher oxygen content than pure MgO. Our finding suggests that MgO2 may be present together or instead of MgO in rocky mantles and rocky planetary cores under highly oxidized conditions.

  19. High-pressure structures of yttrium hydrides

    Science.gov (United States)

    Liu, Lu-Lu; Sun, Hui-Juan; Wang, C. Z.; Lu, Wen-Cai

    2017-08-01

    In this work, the crystal structures of YH3 and YH4 at high pressure (100-250 GPa) have been explored using a genetic algorithm combined with first-principles calculations. New structures of YH3 with space group symmetries of P21/m and I4/mmm were predicted. The electronic structures and the phonon dispersion properties of various YH3 and YH4 structures at different temperatures and pressures were investigated. Among YH3 phases, the P21/m structure of YH3 was found to have a relatively high superconducting transformation temperature T c of 19 K at 120 GPa, which is reduced to 9 K at 200 GPa. Other YH3 structures have much lower T cs. Compared with YH3, the T c of the YH4 compound is much higher, i.e. 94 K at 120 GPa and 55 K at 200 GPa.

  20. High Speed Switching Micoplasma in High Pressure Gases

    Science.gov (United States)

    Wakim, Dani; Staack, David

    2012-10-01

    Micro-plasma discharges with switching times approaching 1 ns are studied at pressures from 1 to 16 atm. Applications of these devices are robust high speed switching transistors able to withstand electric interference, high temperatures and harsh environments. Measured discharge conditions at 250 psia in Nitrogen are: gas temperature 2900 K, discharge diameter ˜7 μm and electron density ˜10^17 cm-3. High speed switching is achieved by taking advantage of rapid dynamics of instabilities at high pressure and high electron density. The capacitance and inductance of the circuit also significantly affect transients. Tradeoffs are observed in switching times. By reducing capacitances from 10 pF to ˜1pF attainment of steady state conditions can be reduced from 1 us to ˜ 20 ns. However current rise times increase from 1 ns at high capacitance to 20 ns at low capacitance. A decrease in switching time with increased pressure is also observed. Also investigated are configurations with a third electrode acting as a gate or trigger and various high temperature (>2000K) materials such as platinum rhodium alloys and ceria stabilized zirconia ceramics for device fabrication.

  1. Synthesis of sodium polyhydrides at high pressures.

    Science.gov (United States)

    Struzhkin, Viktor V; Kim, Duck Young; Stavrou, Elissaios; Muramatsu, Takaki; Mao, Ho-Kwang; Pickard, Chris J; Needs, Richard J; Prakapenka, Vitali B; Goncharov, Alexander F

    2016-01-01

    The only known compound of sodium and hydrogen is archetypal ionic NaH. Application of high pressure is known to promote states with higher atomic coordination, but extensive searches for polyhydrides with unusual stoichiometry have had only limited success in spite of several theoretical predictions. Here we report the first observation of the formation of polyhydrides of Na (NaH3 and NaH7) above 40 GPa and 2,000 K. We combine synchrotron X-ray diffraction and Raman spectroscopy in a laser-heated diamond anvil cell and theoretical random structure searching, which both agree on the stable structures and compositions. Our results support the formation of multicenter bonding in a material with unusual stoichiometry. These results are applicable to the design of new energetic solids and high-temperature superconductors based on hydrogen-rich materials.

  2. Synthesis of sodium polyhydrides at high pressures

    Science.gov (United States)

    Struzhkin, Viktor V.; Kim, Duck Young; Stavrou, Elissaios; Muramatsu, Takaki; Mao, Ho-Kwang; Pickard, Chris J.; Needs, Richard J.; Prakapenka, Vitali B.; Goncharov, Alexander F.

    2016-07-01

    The only known compound of sodium and hydrogen is archetypal ionic NaH. Application of high pressure is known to promote states with higher atomic coordination, but extensive searches for polyhydrides with unusual stoichiometry have had only limited success in spite of several theoretical predictions. Here we report the first observation of the formation of polyhydrides of Na (NaH3 and NaH7) above 40 GPa and 2,000 K. We combine synchrotron X-ray diffraction and Raman spectroscopy in a laser-heated diamond anvil cell and theoretical random structure searching, which both agree on the stable structures and compositions. Our results support the formation of multicenter bonding in a material with unusual stoichiometry. These results are applicable to the design of new energetic solids and high-temperature superconductors based on hydrogen-rich materials.

  3. Food processing by high hydrostatic pressure.

    Science.gov (United States)

    Yamamoto, Kazutaka

    2017-04-01

    High hydrostatic pressure (HHP) process, as a nonthermal process, can be used to inactivate microbes while minimizing chemical reactions in food. In this regard, a HHP level of 100 MPa (986.9 atm/1019.7 kgf/cm(2)) and more is applied to food. Conventional thermal process damages food components relating color, flavor, and nutrition via enhanced chemical reactions. However, HHP process minimizes the damages and inactivates microbes toward processing high quality safe foods. The first commercial HHP-processed foods were launched in 1990 as fruit products such as jams, and then some other products have been commercialized: retort rice products (enhanced water impregnation), cooked hams and sausages (shelf life extension), soy sauce with minimized salt (short-time fermentation owing to enhanced enzymatic reactions), and beverages (shelf life extension). The characteristics of HHP food processing are reviewed from viewpoints of nonthermal process, history, research and development, physical and biochemical changes, and processing equipment.

  4. Percutaneous implantation of thoracic and abdominal aortic prostheses in patients at high surgical risk

    Directory of Open Access Journals (Sweden)

    Juan C Ortiz

    2013-02-01

    intraluminal stent implantation is an alternative. Objective: to analyze the impact of percutaneous implantation of aortic stents in high-risk surgical patients with a minimum of one y ear follow-up. Method: Descriptive study conducted from December 2005 to March 2010 which included 125 patients with thoracic or abdominal aortic aneurysm, meeting surgical criteria by its diameter and that were rejected from surgery due to their high risk. The outcomes were intraoperative death from any cause and aneurysm-related at one, six and twelve months. Complications were defined as vascular occurred during the first thirty days. Results: Abdominal aneurysm was more frequent (70.4%. The overall mortality at 25.7 months follow-up was 14.8%. Of this percentage, 5.2% died from causes related to the aneurysm. One patient died during surgery. 4.3% were reoperated for leaks. There was higher aneurysm-related mortality in the thoracic (14.7 vs. 1.2% p = 0.003 and a trend in those of larger diameter (6.9 vs. 5.7 cm p = 0.210. There was no association between mortality and diabetes mellitus, smoking, heart disease, hypertension or dyslipidemia. Conclusions: aneurysm-related mortality in patients undergoing aortic stent graft is low. Mortality was associated with thoracic aneurysm and to its greater diameter. Complications did not imply an increase in mortality. In conclusion, in patients with aortic aneurysm and high surgical risk rejected for open surgery, percutaneous approach is a safe and effective treatment in a medium-term follow-up.

  5. Rheological assessment of nanofluids at high pressure high temperature

    Science.gov (United States)

    Kanjirakat, Anoop; Sadr, Reza

    2013-11-01

    High pressure high temperature (HPHT) fluids are commonly encountered in industry, for example in cooling and/or lubrications applications. Nanofluids, engineered suspensions of nano-sized particles dispersed in a base fluid, have shown prospective as industrial cooling fluids due to their enhanced rheological and heat transfer properties. Nanofluids can be potentially utilized in oil industry for drilling fluids and for high pressure water jet cooling/lubrication in machining. In present work rheological characteristics of oil based nanofluids are investigated at HPHT condition. Nanofluids used in this study are prepared by dispersing commercially available SiO2 nanoparticles (~20 nm) in a mineral oil. The basefluid and nanofluids with two concentrations, namely 1%, and 2%, by volume, are considered in this investigation. The rheological characteristics of base fluid and the nanofluids are measured using an industrial HPHT viscometer. Viscosity values of the nanofluids are measured at pressures of 100 kPa to 42 MPa and temperatures ranging from 25°C to 140°C. The viscosity values of both nanofluids as well as basefluid are observed to have increased with the increase in pressure. Funded by Qatar National Research Fund (NPRP 08-574-2-239).

  6. High frequency of β-catenin heterozygous mutations in extra-abdominal fibromatosis: a potential molecular tool for disease management

    Science.gov (United States)

    Dômont, J; Salas, S; Lacroix, L; Brouste, V; Saulnier, P; Terrier, P; Ranchère, D; Neuville, A; Leroux, A; Guillou, L; Sciot, R; Collin, F; Dufresne, A; Blay, J-Y; Le Cesne, A; Coindre, J-M; Bonvalot, S; Bénard, J

    2010-01-01

    Background: Fibromatosis comprises distinct clinical entities, including sporadic extra-abdominal fibromatosis, which have a high tendency for recurrence, even after adequate resection. There are no known molecular biomarkers of local recurrence. We searched for β-catenin mutations in a European multicentre series of fibromatosis tumours to relate β-catenin mutational status to disease outcome. Methods: Direct sequencing of exon 3 β-catenin gene was performed for 155 frozen fibromatosis tissues from all topographies. Correlation of outcome with mutation rate and type was performed on the extra-abdominal fibromatosis group (101 patients). Results: Mutations of β-catenin were detected in 83% of all cases. Among 101 extra-abdominal fibromatosis, similar mutation rates (87%) were observed, namely T41A (39.5%), S45P (9%), S45F (36.5%), and deletion (2%). None of the clinico-pathological parameters were found to be significantly associated with β-catenin mutational status. With a median follow-up of 62 months, 51 patients relapsed. Five-year recurrence-free survival was significantly worse in β-catenin-mutated tumours regardless of a specific genotype, compared with wild-type tumours (49 vs 75%, respectively, P=0.02). Conclusion: A high frequency (87%) of β-catenin mutation hallmarks extra-abdominal fibromatosis from a large multicentric retrospective study. Moreover, wild-type β-catenin seems to be an interesting prognostic marker that might be useful in the therapeutic management of extra-abdominal fibromatosis. PMID:20197769

  7. The high-pressure behavior of bloedite

    DEFF Research Database (Denmark)

    Comodi, Paola; Nazzareni, Sabrina; Balic Zunic, Tonci

    2014-01-01

    High-pressure single-crystal synchrotron X‑ray diffraction was carried out on a single crystal of bloedite [Na2Mg(SO4)24H2O] compressed in a diamond-anvil cell. The volume-pressure data, collected up to 11.2 GPa, were fitted by a second- and a third-order Birch-Murnaghan equation of state (EOS......), yielding V0 = 495.6(7) Å3 with K0 = 39.9(6) GPa, and V0 = 496.9(7) Å3, with K0 = 36(1) GPa and K′ = 5.1 (4) GPa-1, respectively. The axial moduli were calculated using a Birch-Murnaghan EOS truncated at the second order, fixing K′ equal to 4, for a and b axes and a third-order Birch-Murnaghan EOS for c...... axis. The results were a0 = 11.08(1) and K0 = 56(3) GPa, b0 = 8.20(2) and K0 = 43(3) GPa, and c0 = 5.528(5), K0 = 40(2) GPa, K′ = 1.7(3) GPa-1. The values of the compressibility for a, b, and c axes are ba = 0.0060(3) GPa-1, bb = 0.0078(5) GPa-1, bc = 0.0083(4) GPa-1 with an anisotropic ratio of ba...

  8. [High blood pressure and physical exercise].

    Science.gov (United States)

    Sosner, P; Gremeaux, V; Bosquet, L; Herpin, D

    2014-06-01

    High blood pressure is a frequent pathology with many cardiovascular complications. As highlighted in guidelines, the therapeutic management of hypertension relies on non-pharmacological measures, which are diet and regular physical activity, but both patients and physicians are reluctant to physical activity prescription. To acquire the conviction that physical activity is beneficial, necessary and possible, we can take into account some fundamental and clinical studies, as well as the feedback of our clinical practice. Physical inactivity is a major risk factor for cardiovascular morbidity and mortality, and hypertension contributes to increase this risk. Conversely, regular practice of physical activity decreases very significantly the risk by up to 60%. The acute blood pressure changes during exercise and post-exercise hypotension differs according to the dynamic component (endurance or aerobic and/or strength exercises), but the repetition of the sessions leads to the chronic hypotensive benefit of physical activity. Moreover, physical activity prescription must take into account the assessment of global cardiovascular risk, the control of the hypertension, and the opportunities and desires of the patient in order to promote good adherence and beneficial lifestyle change. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  9. Engineering Model of High Pressure Moist Air

    Directory of Open Access Journals (Sweden)

    Hyhlík Tomáš

    2017-01-01

    Full Text Available The article deals with the moist air equation of state. There are equations of state discussed in the article, i.e. the model of an ideal mixture of ideal gases, the model of an ideal mixture of real gases and the model based on the virial equation of state. The evaluation of sound speed based on the ideal mixture concept is mentioned. The sound speed calculated by the model of an ideal mixture of ideal gases is compared with the sound speed calculated by using the model based on the concept of an ideal mixture of real gases. The comparison of enthalpy end entropy based on the model of an ideal mixture of ideal gases and the model of an ideal mixture of real gases is performed. It is shown that the model of an ideal mixture of real gases deviates from the model of an ideal mixture of ideal gases only in the case of high pressure. An impossibility of the definition of partial pressure in the mixture of real gases is discussed, where the virial equation of state is used.

  10. The use of a modified, oscillating positive expiratory pressure device reduced fever and length of hospital stay in patients after thoracic and upper abdominal surgery: a randomised trial

    Directory of Open Access Journals (Sweden)

    Xiang-yu Zhang

    2015-01-01

    Full Text Available Question: Does the use of an oscillating positive expiratory pressure (PEP device reduce postoperative pulmonary complications in thoracic and upper abdominal surgical patients? Design: A multi-centre, parallel-group, randomised controlled trial with intention-to-treat analysis, blinding of some outcomes, and concealed allocation. Participants: A total of 203 adults after thoracic or upper abdominal surgery with general anaesthesia. Intervention: Participants in the experimental group used an oscillating PEP device, thrice daily for 5 postoperative days. Both the experimental and control groups received standard medical postoperative management and early mobilisation. Outcome measures: Fever, days of antibiotic therapy, length of hospital stay, white blood cell count, and possible adverse events were recorded for 28 days or until hospital discharge. Results: The 99 participants in the experimental group and 104 in the control group were well matched at baseline and there was no loss to follow-up. Fever affected a significantly lower percentage of the experimental group (22% than the control group (42%, with a RR of 0.56 (95% CI 0.36 to 0.87, NNT 6. Similarly, length of hospital stay was significantly shorter in the experimental group, at 10.7 days (SD 8.1, than in the control group, at 13.3 days (SD 11.1; the mean difference was 2.6 days (95% CI 0.4 to 4.8. The groups did not differ significantly in the need for antibiotic therapy, white blood cell count or total expense of treatment. Conclusion: In adults undergoing thoracic and upper abdominal surgery, postoperative use of an oscillating PEP device resulted in fewer cases of fever and shorter hospital stay. However, antibiotic therapy and total hospital expenses were not significantly reduced by this intervention. Trial registration: NCT00816881. [Zhang X-y, Wang Q, Zhang S, Tan W, Wang Z, Li J (2015 The use of a modified, oscillating positive expiratory pressure device reduced fever and

  11. High pressure fiber optic sensor system

    Science.gov (United States)

    Guida, Renato; Xia, Hua; Lee, Boon K; Dekate, Sachin N

    2013-11-26

    The present application provides a fiber optic sensor system. The fiber optic sensor system may include a small diameter bellows, a large diameter bellows, and a fiber optic pressure sensor attached to the small diameter bellows. Contraction of the large diameter bellows under an applied pressure may cause the small diameter bellows to expand such that the fiber optic pressure sensor may measure the applied pressure.

  12. Abdominal compartment syndrome following abdominoplasty: A case report and review

    Directory of Open Access Journals (Sweden)

    Arash Izadpanah

    2014-01-01

    Full Text Available Abdominoplasty is among the most commonly performed aesthetic procedures in plastic surgery. Despite high complication rate, abdominal contouring procedures are expected to rise in popularity with the advent of bariatric surgery. Patients with a history of gastric bypass surgery have an elevated incidence of small bowel obstruction from internal herniation, which is associated with non-specific upper abdominal pain, nausea, and a decrease in appetite. Internal hernias, when subjected to elevated intra-abdominal pressures, have a high-risk of developing ischemic bowel. We present a case report of patient with previous laparoscopic Roux-en-y gastric bypass who developed acute ischemic bowel leading to abdominal compartment syndrome following abdominoplasty. To the best of our knowledge, this is the first reported case in the literature. We herein emphasise on the subtle symptoms and signs that warrant further investigations in prospective patients for an abdominal contouring procedure with a prior history of gastric bypass surgery.

  13. Sleep Deprivation: A Cause of High Blood Pressure?

    Science.gov (United States)

    ... High blood pressure (hypertension) Is it true that sleep deprivation can cause high blood pressure? Answers from Sheldon ... Cirelli C, et al. Definition and consequences of sleep deprivation. http://www.uptodate.com/home. Accessed March 24, ...

  14. High Blood Pressure, Afib and Your Risk of Stroke

    Science.gov (United States)

    ... Peripheral Artery Disease Venous Thromboembolism Aortic Aneurysm More High Blood Pressure, Afib and Your Risk of Stroke Updated:Sep ... have a stroke for the first time have high blood pressure . And an irregular atrial heart rhythm — a condition ...

  15. High blood pressure - what to ask your doctor

    Science.gov (United States)

    What to ask your doctor about high blood pressure; Hypertension - what to ask your doctor ... problems? What medicines am I taking to treat high blood pressure? Do they have any side effects? What should ...

  16. A Nutritional Strategy for the Treatment of High Blood Pressure.

    Science.gov (United States)

    Podell, Richard N.

    1984-01-01

    Some physicians wonder if high blood pressure can be controlled without the use of drugs and their potential side effects. Current findings concerning nutrition and high blood pressure are presented. (RM)

  17. High Blood Pressure Rates Have Doubled Worldwide Since 1975

    Science.gov (United States)

    ... https://medlineplus.gov/news/fullstory_162069.html High Blood Pressure Rates Have Doubled Worldwide Since 1975 Most of ... News) -- The number of people worldwide with high blood pressure has nearly doubled over the past 40 years, ...

  18. Novel High Pressure Pump-on-a-Chip Technology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — HJ Science & Technology, Inc. proposes to develop a novel high pressure "pump-on-a-chip" (HPPOC) technology capable of generating high pressure and flow rate on...

  19. DNS of High Pressure Supercritical Combustion

    Science.gov (United States)

    Chong, Shao Teng; Raman, Venkatramanan

    2016-11-01

    Supercritical flows have always been important to rocket motors, and more recently to aircraft engines and stationary gas turbines. The purpose of the present study is to understand effects of differential diffusion on reacting scalars using supercritical isotropic turbulence. Focus is on fuel and oxidant reacting in the transcritical region where density, heat capacity and transport properties are highly sensitive to variations in temperature and pressure. Reynolds and Damkohler number vary as a result and although it is common to neglect differential diffusion effects if Re is sufficiently large, this large variation in temperature with heat release can accentuate molecular transport differences. Direct numerical simulations (DNS) for one step chemistry reaction between fuel and oxidizer are used to examine the differential diffusion effects. A key issue investigated in this paper is if the flamelet progress variable approach, where the Lewis number is usually assumed to be unity and constant for all species, can be accurately applied to simulate supercritical combustion.

  20. High-pressure structures of methane hydrate

    CERN Document Server

    Hirai, H; Fujihisa, H; Sakashita, M; Katoh, E; Aoki, K; Yamamoto, Y; Nagashima, K; Yagi, T

    2002-01-01

    Three high-pressure structures of methane hydrate, a hexagonal structure (str. A) and two orthorhombic structures (str. B and str. C), were found by in situ x-ray diffractometry and Raman spectroscopy. The well-known structure I (str. I) decomposed into str. A and fluid at 0.8 GPa. Str. A transformed into str. B at 1.6 GPa, and str. B further transformed into str. C at 2.1 GPa which survived above 7.8 GPa. The fluid solidified as ice VI at 1.4 GPa, and the ice VI transformed to ice VII at 2.1 GPa. The bulk moduli, K sub 0 , for str. I, str. A, and str. C were calculated to be 7.4, 9.8, and 25.0 GPa, respectively.

  1. Urea and deuterium mixtures at high pressures

    Energy Technology Data Exchange (ETDEWEB)

    Donnelly, M., E-mail: m.donnelly-2@sms.ed.ac.uk; Husband, R. J.; Frantzana, A. D.; Loveday, J. S. [Centre for Science at Extreme Conditions and School of Physics and Astronomy, The University of Edinburgh, Erskine Williamson Building, Peter Guthrie Tait Road, The King’s Buildings, Edinburgh EH9 3FD (United Kingdom); Bull, C. L. [ISIS, Rutherford Appleton Laboratory, Oxford Harwell, Didcot OX11 0QX (United Kingdom); Klotz, S. [IMPMC, CNRS UMR 7590, Université P and M Curie, 4 Place Jussieu, 75252 Paris (France)

    2015-03-28

    Urea, like many network forming compounds, has long been known to form inclusion (guest-host) compounds. Unlike other network formers like water, urea is not known to form such inclusion compounds with simple molecules like hydrogen. Such compounds if they existed would be of interest both for the fundamental insight they provide into molecular bonding and as potential gas storage systems. Urea has been proposed as a potential hydrogen storage material [T. A. Strobel et al., Chem. Phys. Lett. 478, 97 (2009)]. Here, we report the results of high-pressure neutron diffraction studies of urea and D{sub 2} mixtures that indicate no inclusion compound forms up to 3.7 GPa.

  2. Simulating a high pressure die casting

    Energy Technology Data Exchange (ETDEWEB)

    Goldak, J.; Zhou, J.; Downey, D.; Aldea, V.; Li, G.; Mocanita, M. [Carleton Univ., Ottawa, Ontario (Canada)

    2000-07-01

    High pressure die casting is simulated for parts with complex geometry such as a large automotive transmission case. The closed die is filled in approximately 40 ms, the casting cools in the closed die for approximately 40s, to open the die, eject the casting and spray the die cavity surface requires another 40s. This 3D cyclic process is simulated using the following coupled composite solvers: the energy equation in the die and in the casting with solidification; filling of the casting by a droplet or a Navier-Stokes solver, and thermal stress analysis of the casting machine, casting and die during the cycle. This thermal analysis can be done for both starting and stopping transients and for the cyclic steady state. The software enables this analysis to be done almost automatically by designers. (author)

  3. Effect of high pressure on mesophilic lactic fermentation streptococci

    Science.gov (United States)

    Reps, A.; Kuźmicka, M.; Wiśniewska, K.

    2008-07-01

    The research concerned the effect of high pressure on mesophilic lactic fermentation streptococci, present in two cheese-making commercial inocula produced by Christian-Hansen. Water solutions of inocula were pressurized at 50-800 MPa, at room temperature, for 30-120 min. Pressurization at 50-100 MPa slightly increased or reduced the number of lactic streptococci, depending on the inoculum and pressurization time. Pressurization at 200 MPa caused a reduction in the number of streptococci by over 99.9%, whereas the pressure of 400 MPa and above almost completely inactivated streptococci. Pressurization also reduced the dynamics of microorganism growth and acidification, to the degree depending on the pressure.

  4. Use of biological meshes for abdominal wall reconstruction in highly contaminated fields

    Institute of Scientific and Technical Information of China (English)

    Andrea; Cavallaro; Emanuele; Lo; Menzo; Maria; Di; Vita; Antonio; Zanghì; Vincenzo; Cavallaro; Pier; Francesco; Veroux; Alessandro; Cappellani

    2010-01-01

    Abdominal wall defects and incisional hernias represent a challenging problem. In particular, when a synthetic mesh is applied to contaminated wounds, its removal is required in 50%-90% of cases. Biosynthetic meshes are the newest tool available to surgeons and they could have a role in ventral hernia repair in a potential-ly contaminated field. We describe the use of a sheet of bovine pericardium graft in the reconstruction of abdominal wall defect in two patients. Bovine pericardium graft was placed in th...

  5. What about African Americans and High Blood Pressure?

    Science.gov (United States)

    ... whites. • Heredity —A tendency to have high blood pressure runs in families. • Age — In general, the older you get, the greater your chance of developing high blood pressure. • Sex — Men tend to develop high blood pressure ...

  6. Let's Talk about High Blood Pressure and Stroke

    Science.gov (United States)

    ... stroke. How does high blood pressure increase stroke risk? High blood pressure is the single most important risk factor for ... vessel ruptures over time. Who is at higher risk for HBP? People with a family history of high blood pressure African-Americans People age 35 or older People ...

  7. Metabolic Activity of Bacteria at High Pressure

    Science.gov (United States)

    Picard, A.; Daniel, I.; Oger, P.

    2008-12-01

    Over the last 20 years, there has been increasing evidence for the presence of a large number of microbes in the oceanic subsurface. Such a habitat has a very low energy input because it is deprived of light. A few meters below the sediment surface, conditions are already anoxic in most cases, sulfate reduction and/or methanogenesis becoming thus the primary respiratory reactions of organic matter. Neither the fate of methanogenesis, nor the fate of Dissimilatory Metal-Reduction (DMR) has been investigated so far as a function of pressure. For this reason, we measured experimentally the pressure limits of microbial anaerobic energetic metabolism. In practice, we measured in situ the kinetics of selenite respiration by the bacterial model Shewanella oneidensis MR-1 under high hydrostatic pressure (HHP) between 0 and 150 MPa at 30°C. MR-1 stationary-phase cells were used in Luria-Bertani (LB) medium amended with lactate as an additional electron donor and sodium selenite as an electron acceptor. In situ measurements were performed by X- ray Absorption Near-Edge Structure (XANES) spectroscopy in both a diamond-anvil cell and an autoclave. A red precipitate of amorphous Se(0) was virtually observed at any pressure to 150 MPa. A progressive reduction of selenite Se(IV) into selenium Se(0) was also observed in the evolution of XANES spectra with time. All kinetics between 0.1 and 150 MPa can be adjusted to a first order kinetic law. MR-1 respires all available selenite up to 60 MPa. Above 60 MPa, the respiration yield decreases linearly as a function of pressure and reaches 0 at 155 ±5 MPa. This indicates that selenite respiration by Shewanella oneidensis MR-1 stops at about 155 MPa, whereas its growth is arrested at 50 MPa. Hence, the present results show that the respiration of selenium by the strain MR-1 occurs efficiently up to 60 MPa and 30°C, i.e. from the surface of a continental sediment to an equivalent depth of about 2 km, or beneath a 5-km water column and

  8. Comparative study of the microvascular blood flow in the intestinal wall, wound contraction and fluid evacuation during negative pressure wound therapy in laparostomy using the V.A.C. abdominal dressing and the ABThera open abdomen negative pressure therapy system.

    Science.gov (United States)

    Lindstedt, Sandra; Malmsjö, Malin; Hlebowicz, Joanna; Ingemansson, Richard

    2015-02-01

    This study aimed to compare the changes in microvascular blood flow in the small intestinal wall, wound contraction and fluid evacuation, using the established V.A.C. abdominal dressing (VAC dressing) and a new abdominal dressing, the ABThera open abdomen negative pressure therapy system (ABThera dressing), in negative pressure wound therapy (NPWT). Midline incisions were made in 12 pigs that were subjected to treatment with NPWT using the VAC or ABThera dressing. The microvascular blood flow in the intestinal wall was measured before and after the application of topical negative pressures of −50, −75 and −125mmHg using laser Doppler velocimetry. Wound contraction and fluid evacuation were also measured. Baseline blood flow was defined as 100% in all settings. The blood flow was significantly reduced to 64·6±6·7% (P blood flow was significantly reduced to 39·6±6·7% (P blood flow could be observed between the two groups. The ABThera system afforded significantly better fluid evacuation from the wound, better drainage of the abdomen and better wound contraction than the VAC dressing.

  9. Prevention of metabolic disorders with telmisartan and indapamide in a Chinese population with high-normal blood pressure.

    Science.gov (United States)

    Peng, Jie; Zhao, Yingxin; Zhang, Hua; Liu, Zhendong; Wang, Zhihao; Tang, Mengxiong; Zhong, Ming; Lu, Fanghong; Zhang, Wei

    2015-02-01

    High-normal blood pressure is considered a precursor of stage 1 hypertension that is associated with metabolic disorders. This study aims to investigate whether the pharmacologic treatment of high-normal blood pressure affects metabolism, especially in abdominally obese individuals, and the pharmacoeconomics of two antihypertensive agents, telmisartan and indapamide. Subjects with high-normal blood pressure were randomly assigned to receive telmisartan, indapamide or placebo for 3 years. All the subjects were instructed to modify their lifestyle to reduce blood pressure throughout the study. A total of 221 subjects were randomly assigned to telmisartan, 213 to indapamide and 230 to placebo. After the 3-year intervention, blood pressure was lower in the telmisartan and indapamide groups (Ptelmisartan group was lower during the first 2 years (P0.05). The percentage of subjects with metabolic syndrome was significantly decreased in the telmisartan and indapamide groups (Ptelmisartan group for subjects with abdominal obesity (Ptelmisartan was ~1.86 times higher than for indapamide for a similar antihypertensive effect. The intervention for high-normal blood pressure with telmisartan and indapamide appeared to be feasible and reduced the risk of metabolic syndrome. Telmisartan was more effective, whereas indapamide had better pharmacoeconomic benefits.

  10. Prediction of Outcome After Emergency High-Risk Intra-abdominal Surgery Using the Surgical Apgar Score

    DEFF Research Database (Denmark)

    Cihoric, Mirjana; Toft Tengberg, Line; Bay-Nielsen, Morten

    2016-01-01

    BACKGROUND: With current literature quoting mortality rates up to 45%, emergency high-risk abdominal surgery has, compared with elective surgery, a significantly greater risk of death and major complications. The Surgical Apgar Score (SAS) is predictive of outcome in elective surgery, but has never...... been validated exclusively in an emergency setting. METHODS: A consecutive prospective single-center cohort study of 355 adults undergoing emergency high-risk abdominal surgery between June 2013 and May 2014 is presented. The primary outcome measure was 30-day mortality. Secondary outcome measures were...... the incidence of both outcomes. Area under the curve was used to demonstrate the scores' discriminatory power. RESULTS: One hundred eighty-one (51.0%) patients developed minor or no complications. The overall incidence of major complications was 32.7% and the overall death rate was 16.3%. Risk of major...

  11. Probing Hydrogen Diffusion under High Pressure

    Science.gov (United States)

    Bove, L. E.; Klotz, S.; Strassle, T.; Saitta, M.

    2012-12-01

    The study of the microscopic mechanism governing hydrogen and hydrogen-based liquids (as water, ammonia and methane) diffusion is crucial for a variety of scientific issues spanning most of natural sciences. As an example, characterizing hydrogen diffusion in a confined medium, like in porous systems or zeolites, is fundamental in problems relating to environment, hydrogen storage and industrial applications [1]. The presence of water diffusion in the minerals of the Earth's mantle have strong incidence on the processes governing volcanic eruptions and intermediate-depth seismicity. As last example, knowing in details the microscopic dynamics of hydrogen-based simple liquids under extreme conditions is essential in order to interpret observations and develop models of planet interiors [2]. On the other hand, water and other simple hydrogen-based liquids have always been key systems in the development of modern condensed-matter physics, because of their simple electronic structure and the peculiar properties deriving from the hydrogen-bond network. Their high compressibility and chemical reactivity have made these systems very challenging to study experimentally under static high P-T conditions. In the last few years, a large effort has been undertaken by several groups around the world [2] to extend the static and dynamic techniques to high temperatures and pressures, a program in which our group has been actively involved [3-6]. However, while the structure of water and other hydrogenated liquids of geological interest, is now known up to almost 20 GPa, the study of their transport properties greatly lags behind. We have recently developed a new large-volume gasket-anvil ensemble for the Paris-Edinburgh press based on a novel toroidal design [7], which allows to perform quasi elastic neutron scattering measurements on hydrogen based liquids up to one order of magnitude higher pressures (5 GPa) respect to what was achievable with standard methods [8]. The large

  12. Continuous Non-invasive finger cuff CareTaker® comparable to invasive intra-arterial pressure in patients undergoing major intra-abdominal surgery.

    Science.gov (United States)

    Gratz, Irwin; Deal, Edward; Spitz, Francis; Baruch, Martin; Allen, I Elaine; Seaman, Julia E; Pukenas, Erin; Jean, Smith

    2017-03-21

    Despite increased interest in non-invasive arterial pressure monitoring, the majority of commercially available technologies have failed to satisfy the limits established for the validation of automatic arterial pressure monitoring by the Association for the Advancement of Medical Instrumentation (AAMI). According to the ANSI/AAMI/ISO 81060-2:2013 standards, the group-average accuracy and precision are defined as acceptable if bias is not greater than 5 mmHg and standard deviation is not greater than 8 mmHg. In this study, these standards are used to evaluate the CareTaker® (CT) device, a device measuring continuous non-invasive blood pressure via a pulse contour algorithm called Pulse Decomposition Analysis. A convenience sample of 24 patients scheduled for major abdominal surgery were consented to participate in this IRB approved pilot study. Each patient was monitored with a radial arterial catheter and CT using a finger cuff applied to the contralateral thumb. Hemodynamic variables were measured and analyzed from both devices for the first thirty minutes of the surgical procedure including the induction of anesthesia. The mean arterial pressure (MAP), systolic and diastolic blood pressures continuously collected from the arterial catheter and CT were compared. Pearson correlation coefficients were calculated between arterial catheter and CT blood pressure measurements, a Bland-Altman analysis, and polar and 4Q plots were created. The correlation of systolic, diastolic, and mean arterial pressures were 0.92, 0.86, 0.91, respectively (p arterial pressures, respectively with a standard deviation of 7.34, 6.47, 5.33 mmHg for systolic, diastolic, and mean arterial pressures, respectively (p pressure measured using the non-invasive CT device was shown to correlate well with the arterial catheter measurements. Larger studies are needed to confirm these results in more varied settings. Most patients exhibited very good agreement between methods. Results were

  13. High-sensitive cardiac troponin T measurements in prediction of non-cardiac complications after major abdominal surgery.

    Science.gov (United States)

    Noordzij, P G; van Geffen, O; Dijkstra, I M; Boerma, D; Meinders, A J; Rettig, T C D; Eefting, F D; van Loon, D; van de Garde, E M W; van Dongen, E P A

    2015-06-01

    Postoperative non-cardiac complication rates are as high as 11-28% after high-risk abdominal procedures. Emerging evidence indicates that postoperative cardiac troponin T elevations are associated with adverse outcome in non-cardiac surgery. The aim of this study was to determine the relationship between postoperative high-sensitive cardiac troponin T elevations and non-cardiac complications in patients after major abdominal surgery. This prospective observational single-centre cohort study included patients at risk for coronary artery disease undergoing elective major abdominal surgery. Cardiac troponin was measured before surgery and at day 1, 3, and 7. Multivariable logistic regression analysis was performed to examine the adjusted association for different cut-off concentrations of postoperative myocardial injury and non-cardiac outcome. In 203 patients, 690 high-sensitive cardiac troponin T measurements were performed. Fifty-three patients (26%) had a non-cardiac complication within 30 days after surgery. Hospital mortality was 4% (8/203). An increase in cardiac troponin T concentration ≥100% compared with baseline was a superior independent predictor of non-cardiac postoperative clinical complications (adjusted odds ratio 4.3, 95% confidence interval 1.8-10.1, Pcardiac troponin T increase ≥100% is a strong predictor of non-cardiac 30 day complications, increased hospital stay and hospital mortality in patients undergoing major abdominal surgery. NCT02150486. © 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.

  14. High-pressure superconducting state in hydrogen

    Science.gov (United States)

    Duda, A. M.; Szczȩśniak, R.; Sowińska, M. A.; Kosiacka, A. H.

    2016-10-01

    The paper determines the thermodynamic parameters of the superconducting state in the metallic atomic hydrogen under the pressure at 1 TPa, 1.5 TPa, and 2.5 TPa. The calculations were conducted in the framework of the Eliashberg formalism. It has been shown that the critical temperature is very high (in the range from 301.2 K to 437.3 K), as well as high are the values of the electron effective mass (from 3.43me to 6.88me), where me denotes the electron band mass. The ratio of the low-temperature energy gap to the critical temperature explicitly violates the predictions of the BCS theory: 2 Δ (0) /kB TC ∈ . Additionally, the free energy difference between the superconducting and normal state, the thermodynamic critical field, and the specific heat of the superconducting state have been determined. Due to the significant strong-coupling and retardation effects those quantities cannot be correctly described in the framework of the BCS theory.

  15. Abdominal Obesity and Insulin Resistance in People Exposed to Moderate-to-High Levels of Dioxin.

    Directory of Open Access Journals (Sweden)

    Jung-Wei Chang

    Full Text Available Obesity, a risk factor for developing metabolic complications, is a major public health problem. Abdominal obesity is strongly accompanied by a cluster of metabolic abnormalities characterized by insulin resistance. The link between persistent organic pollutants (POPs and insulin resistance has been investigated in animal and epidemiological studies. We aimed to examine whether insulin resistance is greater in people with abdominal obesity (AO and concomitant exposure to serum dioxins (PCDD/Fs. We conducted a cross-sectional descriptive study of 2876 participants living near a PCDD/Fs contaminated area. Seventeen 2,3,7,8-substituted PCDD/Fs congeners were measured, and then the associations between the main predictor variable, serum TEQDF-1998, abdominal obesity (AO, dependent variables, and insulin resistance were examined. Twelve of the 17 congeners, widely distributed among PCDDs, and PCDFs, had trends for associations with abdominal adiposity. In men, the highest quintiles of 1,2,3,7,8-PeCDF; 1,2,3,7,8-PeCDD; 2,3,7,8-TCDD; 2,3,7,8-TCDF; and 2,3,4,7,8-PeCDF had the top five adjusted odds ratios (AORs + 95% confidence intervals (CIs:[4.2; 2.7-6.4], [3.6; 2.3-5.7], [3.2; 2.1-5.0], [3.0; 2.0-4.5], and [2.9; 1.9-4.7], respectively. In women, the highest quintiles of 1,2,3,4,7,8,9-HpCDF; 1,2,3,6,7,8-HxCDF; and 1,2,3,4,6,7,8-HpCDF had the top three AORs + 95% CIs:[3.0; 1.9-4.7], [2.0; 1.3-3.1], and [1.9; 1.3-2.9], respectively. After confounding factors had been adjusted for, men, but not women, with higher serum TEQDF-1998 levels or abdominal obesity had a significantly (Ptrend < 0.001 greater risk for abnormal insulin resistance. The groups with the highest joint serum TEQDF-1998 and abdominal obesity levels were associated with elevated insulin resistance at 5.0 times the odds of the groups with the lowest joint levels (AOR 5.23; 95% CI: 3.53-7.77. We hypothesize that serum TEQDF-1998 and abdominal obesity affect the association with insulin

  16. The Influence of Dual Pressure Biofeedback Units on Pelvic Rotation and Abdominal Muscle Activity during the Active Straight Leg Raise in Women with Chronic Lower Back Pain.

    Science.gov (United States)

    Noh, Kyung-Hee; Kim, Ji-Won; Kim, Gyoung-Mo; Ha, Sung-Min; Oh, Jae-Seop

    2014-05-01

    [Purpose] This study was performed to assess the influence of applying dual pressure biofeedback units (DPBUs) on the angle of pelvic rotation and abdominal muscle activity during the active straight leg raise (ASLR). [Subjects] Seventeen patients with low-back pain (LBP) participated in this study. [Methods] The subjects were asked to perform an active straight leg raise (ASLR) without a PBU, with a single PBU, and with DPBUs. The angles of pelvic rotation were measured using a three-dimensional motion-analysis system, and the muscle activity of the bilateral internal oblique abdominis (IO), external oblique abdominis (EO), and rectus abdominis (RA) was recorded using surface electromyography (EMG). One-way repeated-measures ANOVA was performed to determine the rotation angles and muscle activity under the three conditions. [Results] The EMG activity of the ipsilateral IO, contralateral EO, and bilateral RA was greater and pelvic rotation was lower with the DPBUs than with no PBU or a single PBU. [Conclusion] The results of this study suggest that applying DPBUs during ASLR is effective in decreasing unwanted pelvic rotation and increasing abdominal muscle activity in women with chronic low back pain.

  17. High-pressure Raman spectroscopy of carbon onions and nanocapsules

    Science.gov (United States)

    Guo, J. J.; Liu, G. H.; Wang, X. M.; Fujita, T.; Xu, B. S.; Chen, M. W.

    2009-08-01

    We report high-pressure Raman spectra of carbon onions and nanocapsules investigated by diamond anvil cell experiments. The pressure coefficient and elastic behavior of carbon onions and nanocapsules are found to be very similar to those of multiwall carbon nanotubes. Additionally, detectable structure changes, particularly the collapse of the concentric graphite structure, cannot been seen at pressures as high as ˜20 GPa, demonstrating that carbon onions and nanocapsules have significant hardness and can sustain very high pressures.

  18. High Chamber Pressure, Light Weight Thrusters Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The performance liquid propellant engines can be significantly improved by increasing both combustion temperature and pressure and reducing engine weight. State of...

  19. Numerical simulation of high pressure water jet impacting concrete

    Science.gov (United States)

    Liu, Jialiang; Wang, Mengjin; Zhang, Di

    2017-08-01

    High pressure water jet technology is an unconventional concrete crushing technology. In order to reveal the mechanism of high pressure water jet impacting concrete, it built a three-dimensional numerical model of high pressure water jet impacting concrete based on fluid mechanics and damage mechanics. And the numerical model was verified by theoretical analysis and experiments. Based on this model, it studied the stress characteristics in concrete under high pressure water jet impacting at different time, and quantified the damage evolution rules in concrete along the water jet radial direction. The results can provide theoretical basis and guidance for the high pressure water jet crushing concrete technology.

  20. High pressure gas vessels for neutron scattering experiments

    CERN Document Server

    Done, R; Evans, B E; Bowden, Z A

    2010-01-01

    The combination of high pressure techniques with neutron scattering proves to be a powerful tool for studying the phase transitions and physical properties of solids in terms of inter-atomic distances. In our report we are going to review a high pressure technique based on a gas medium compression. This technique covers the pressure range up to ~0.7GPa (in special cases 1.4GPa) and typically uses compressed helium gas as the pressure medium. We are going to look briefly at scientific areas where high pressure gas vessels are intensively used in neutron scattering experiments. After that we are going to describe the current situation in high pressure gas technology; specifically looking at materials of construction, designs of seals and pressure vessels and the equipment used for generating high pressure gas.

  1. Automated high pressure cell for pressure jump x-ray diffraction

    Science.gov (United States)

    Brooks, Nicholas J.; Gauthe, Beatrice L. L. E.; Terrill, Nick J.; Rogers, Sarah E.; Templer, Richard H.; Ces, Oscar; Seddon, John M.

    2010-06-01

    A high pressure cell for small and wide-angle x-ray diffraction measurements of soft condensed matter samples has been developed, incorporating a fully automated pressure generating network. The system allows both static and pressure jump measurements in the range of 0.1-500 MPa. Pressure jumps can be performed as quickly as 5 ms, both with increasing and decreasing pressures. Pressure is generated by a motorized high pressure pump, and the system is controlled remotely via a graphical user interface to allow operation by a broad user base, many of whom may have little previous experience of high pressure technology. Samples are loaded through a dedicated port allowing the x-ray windows to remain in place throughout an experiment; this facilitates accurate subtraction of background scattering. The system has been designed specifically for use at beamline I22 at the Diamond Light Source, United Kingdom, and has been fully integrated with the I22 beamline control systems.

  2. Automated high pressure cell for pressure jump x-ray diffraction.

    Science.gov (United States)

    Brooks, Nicholas J; Gauthe, Beatrice L L E; Terrill, Nick J; Rogers, Sarah E; Templer, Richard H; Ces, Oscar; Seddon, John M

    2010-06-01

    A high pressure cell for small and wide-angle x-ray diffraction measurements of soft condensed matter samples has been developed, incorporating a fully automated pressure generating network. The system allows both static and pressure jump measurements in the range of 0.1-500 MPa. Pressure jumps can be performed as quickly as 5 ms, both with increasing and decreasing pressures. Pressure is generated by a motorized high pressure pump, and the system is controlled remotely via a graphical user interface to allow operation by a broad user base, many of whom may have little previous experience of high pressure technology. Samples are loaded through a dedicated port allowing the x-ray windows to remain in place throughout an experiment; this facilitates accurate subtraction of background scattering. The system has been designed specifically for use at beamline I22 at the Diamond Light Source, United Kingdom, and has been fully integrated with the I22 beamline control systems.

  3. Selected studies of magnetism at high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Hearne, G.R. [University of the Witwatersrand, Johannesburg (South Africa). Dept. of Physics; Pasternak, M.P. [Tel-Aviv Univ. (Israel). School of Physics and Astronomy; Taylor, R.D. [Los Alamos National Lab., NM (United States)

    1995-09-01

    Most previous studies of magnetism in various compounds under extreme conditions have been conducted over a wide pressure range at room temperature or over a wide range of cryogenic temperatures at pressures below 20 GPa (200 kbar). We present some of the most recent studies of magnetism over an extended range of temperatures and pressures far beyond 20 GPa, i.e., in regions of pressure-temperature (P-T) where magnetism has been largely unexplored. Recent techniques have permitted investigations of magnetism in selected 3d transition metal compounds in regions of P-T where physical properties may be drastically modified; related effects have often been seen in selected doping studies at ambient pressures.

  4. Equation of state of unreacted high explosives at high pressures

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, C-S

    1998-08-14

    Isotherms of unreacted high explosives (HMX, RDX, and PETN) have been determined to quasi-hydrostatic high pressures below 45 GPa, by using a diamond-anvil cell angle-resolved synchrotron x-ray diffraction method. The equation-of-state parameters (bulk modulus Bo, and its derivatives B' ) are presented for the 3rd-order Birch-Murnaghan formula based on the measured isotherms. The results are also used to retrieve unreacted Hugoniots in these high explosives and to develop the equations of state and kinetic models for composite high explolsivcs such as XTX-8003 and LX-04. The evidence of shear-induced chemistry of HMX in non-hydrostatic conditions is also presented.

  5. [Abdominal pregnancy, institutional experience].

    Science.gov (United States)

    Bonfante Ramírez, E; Bolaños Ancona, R; Simón Pereyra, L; Juárez García, L; García-Benitez, C Q

    1998-07-01

    Abdominal pregnancy is a rare entity, which has been classified as primary or secondary by Studiford criteria. A retrospective study, between January 1989 and December 1994, realized at Instituto Nacional de Perinatología, found 35,080 pregnancies, from which 149 happened to be ectopic, and 6 of them were abdominal. All patients belonged to a low income society class, age between 24 and 35 years, and average of gestations in 2.6. Gestational age varied from 15 weeks to 32.2 weeks having only one delivery at term with satisfactory postnatal evolution. One patient had a recurrent abdominal pregnancy, with genital Tb as a conditional factor. Time of hospitalization varied from 4 to 5 days, and no further patient complications were reported. Fetal loss was estimated in 83.4%. Abdominal pregnancy is often the sequence of a tubarian ectopic pregnancy an when present, it has a very high maternal mortality reported in world literature, not found in this study. The stated frequency of abdominal pregnancy is from 1 of each 3372, up to 1 in every 10,200 deliveries, reporting in the study 1 abdominal pregnancy in 5846 deliveries. The study had two characteristic entities one, the recurrence and two, the delivery at term of one newborn. Abdominal pregnancy accounts for 4% of all ectopic pregnancies. Clinical findings in abdominal pregnancies are pain, transvaginal bleeding and amenorrea, being the cardinal signs of ectopic pregnancy.

  6. High Pressure Laminates with Antimicrobial Properties

    Directory of Open Access Journals (Sweden)

    Sandra Magina

    2016-02-01

    Full Text Available High-pressure laminates (HPLs are durable, resistant to environmental effects and good cost-benefit decorative surface composite materials with special properties tailored to meet market demand. In the present work, polyhexamethylene biguanide (PHMB was incorporated for the first time into melamine-formaldehyde resin (MF matrix on the outer layer of HPLs to provide them antimicrobial properties. Chemical binding of PHMB to resin matrix was detected on the surface of produced HPLs by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR. Antimicrobial evaluation tests were carried out on the ensuing HPLs doped with PHMB against gram-positive Listeria innocua and gram-negative Escherichia coli bacteria. The results revealed that laminates prepared with 1.0 wt % PHMB in MF resin were bacteriostatic (i.e., inhibited the growth of microorganisms, whereas those prepared with 2.4 wt % PHMB in MF resin exhibited bactericidal activity (i.e., inactivated the inoculated microorganisms. The results herein reported disclose a promising strategy for the production of HPLs with antimicrobial activity without affecting basic intrinsic quality parameters of composite material.

  7. Spectroscopy of high pressure cesium discharge

    Science.gov (United States)

    Pichler, Goran; Pichler, Marin

    2008-05-01

    Near UV, visible and NIR spectrum of Cs lamp has been studied in many experimental situations. We concentrate on the spectral region around resonance lines where numerous satellite bands appear. We followed the appearance of these satellite bands after the ignition. They first appear in emission, and then in absorption, due to the steady increase of cesium atom density. The origin of the satellite bands have been described ootnotetextD. Veza, R. Beuc, S. Milosevi' c and G. Pichler, Eur. Phys. J. D, 2, 45 (1998)^,ootnotetextR. Beuc, H. Skenderovi' c, T. Ban, D. Veza, G. Pichler, W. Meyer, Eur. Phys. J.D 15, 209 (2001). We observed the satellite band intensity behavior in several different burners filled with cesium and xenon. In one burner made out of crystalline sapphire we observed interesting spatial distribution of entire visible spectrum, during evolution in time after the ignition. The intensity behavior of satellite bands in the near-infrared spectral region will be used in further development of the white light source with pulsed cesium high-pressure discharge.

  8. Functional Sub-states by High-pressure Macromolecular Crystallography.

    Science.gov (United States)

    Dhaussy, Anne-Claire; Girard, Eric

    2015-01-01

    At the molecular level, high-pressure perturbation is of particular interest for biological studies as it allows trapping conformational substates. Moreover, within the context of high-pressure adaptation of deep-sea organisms, it allows to decipher the molecular determinants of piezophily. To provide an accurate description of structural changes produced by pressure in a macromolecular system, developments have been made to adapt macromolecular crystallography to high-pressure studies. The present chapter is an overview of results obtained so far using high-pressure macromolecular techniques, from nucleic acids to virus capsid through monomeric as well as multimeric proteins.

  9. Enhanced MgB2 Superconductivity Under High Pressure

    Institute of Scientific and Technical Information of China (English)

    刘振兴; 靳常青; 游江洋; 李绍春; 朱嘉林; 禹日成; 李风英; 苏少奎

    2002-01-01

    We report on in situ high-pressure studies up to 1.0 GPa on the MgB2 superconductor which was high-pressure synthesized. The as-prepared sample is of high quality in terms of sharp superconducting transition (Tc) at 39K from the magnetic measurements. The in situ high-pressure measurements were carried out using a Be-Cu piston-cylinder-type instrument with mixed oil as the pressure transmitting medium which warrants a quasihydrostatic pressure environment at low temperature. The superconducting transitions were measured using the electrical conductance method. It is found that Tc increases by more than 1 K with pressure in the low-pressure range, before the Tc value decreases with the further increase of the pressure.

  10. Imaging in (high pressure) Micromegas TPC detectors

    Science.gov (United States)

    Luzón, G.; Cebrián, S.; Castel, J.; Dafni, Th.; Galán, J.; Garza, J. G.; Irastorza, I. G.; Iguaz, F. J.; Mirallas, H.; Ruíz-Choliz, E.

    2016-11-01

    The T-REX project of the group of the University of Zaragoza includes a number of R&D and prototyping activities to explore the applicability of gaseous Time Projection Chambers (TPCs) with Micromesh Gas Structures (Micromegas) in rare event searches where the pattern recognition of the signal is crucial for background discrimination. In the CAST experiment (CERN Axion Solar Telescope) a background level as low as 0.8 × 10-6 counts keV-1 cm-2 s-1 was achieved. Prototyping and simulations promise a 105 better signal-to-noise ratio than CAST for the future IAXO (International Axion Observatory) using x-ray telescopes. A new strategy is also explored in the search of WIMPS based on high gas pressure: the TREX-DM experiment, a low energy threshold detector. In both cases, axion and WIMP searches, the image of the expected signal is quite simple: a one cluster deposition coming from the magnet bore in the case of axions and, if possible, with a tadpole form in the case of WIMPs. It is the case of double beta decay (DBD) where imaging and pattern recognition play a major role. Results obtained in Xe + trimethylamine (TMA) mixture point to a reduction in electron diffusion which improves the quality of the topological pattern, with a positive impact on the discrimination capability, as shown in TREX-ββ prototype. Microbulk Micromegas are able to image the DBD ionization signature with high quality while, at the same time, measuring its energy deposition with a resolution of at least a ~ 3% FWHM at the transition energy Qββ and even better (up to ~ 1% FWHM) as extrapolated from low energy events. That makes Micromegas-based HPXe TPC a very competitive technique for the next generation DBD experiments (as PANDAX-III). Here, it will be shown the last results of the TREX project detectors and software concerning Axions, Dark matter and double beta decay.

  11. Hydraulic High Pressure Valve Controller Using the In-Situ Pressure Difference

    Science.gov (United States)

    Bao, Xiaoqi (Inventor); Sherrit, Stewart (Inventor); Badescu, Mircea (Inventor); Bar-Cohen, Yoseph (Inventor); Hall, Jeffery L. (Inventor)

    2016-01-01

    A hydraulic valve controller that uses an existing pressure differential as some or all of the power source for valve operation. In a high pressure environment, such as downhole in an oil or gas well, the pressure differential between the inside of a pipe and the outside of the pipe may be adequately large to drive a linear slide valve. The valve is operated hydraulically by a piston in a bore. When a higher pressure is applied to one end of the bore and a lower pressure to the other end, the piston moves in response to the pressure differential and drives a valve attached to it. If the pressure differential is too small to drive the piston at a sufficiently high speed, a pump is provided to generate a larger pressure differential to be applied. The apparatus is conveniently constructed using multiport valves, which can be rotary valves.

  12. High Toughness Light Weight Pressure Vessel Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Proposed is a pressure vessel with 25% better Fracture Strength over equal strength designed Fiberglass to help reduce 10 to 25% weight for aerospace use. Phase I is...

  13. Propagation Limits of High Pressure Cool Flames

    Science.gov (United States)

    Ju, Yiguang

    2016-11-01

    The flame speeds and propagation limits of premixed cool flames at elevated pressures with radiative heat loss are numerically modelled using dimethyl ether mixtures. The primary focus is paid on the effects of pressure, mixture dilution, flame size, and heat loss on cool flame propagation. The results showed that cool flames exist on both fuel lean and fuel rich sides and thus dramatically extend the lean and rich flammability limits. There exist three different flame regimes, hot flame, cool flame, and double flame. A new flame flammability diagram including both cool flames and hot flames is obtained at elevated pressure. The results show that pressure significantly changes cool flame propagation. It is found that the increases of pressure affects the propagation speeds of lean and rich cool flames differently due to the negative temperature coefficient effect. On the lean side, the increase of pressure accelerates the cool flame chemistry and shifts the transition limit of cool flame to hot flame to lower equivalence ratio. At lower pressure, there is an extinction transition from hot flame to cool flame. However, there exists a critical pressure above which the cool flame to hot flame transition limit merges with the lean flammability limit of the hot flame, resulting in a direct transition from hot flame to cool flame. On the other hand, the increase of dilution reduces the heat release of hot flame and promotes cool flame formation. Moreover, it is shown that a smaller flame size and a higher heat loss also extend the cool flame transition limit and promote cool flame formation.

  14. Evidence of Tetragonal Nanodomains in the high pressure polymorph

    Energy Technology Data Exchange (ETDEWEB)

    Ehm, L.; Borkowski, L.A.; Parise J.B.; Ghose, S.; Chen, Z.

    2010-12-17

    The pressure induced P4mm {yields} Pm{bar 3}m phase transition in BaTiO{sub 3} perovskite was investigated by x-ray total scattering. The evolution of the structure was analyzed by fitting pair distribution functions over a pressure range from ambient pressure up to 6.85(7) GPa. Evidence for the existence of tetragonal ferroelectric nanodomains at high pressure was found. The average size of the nanodomains in the high-pressure phase decreases with increasing pressure. Extrapolation of the domain size to pressures higher than studied experimentally suggests a disappearance of the ferroelectric domains at about 9.3(5) GPa and a cubic symmetry of BaTiO{sub 3} high-pressure phase.

  15. Abdominal and Pelvic CT

    Medline Plus

    Full Text Available ... contrast materials and a metallic taste in your mouth that lasts for at most a minute or ... can diagnose many causes of abdominal pain or injury from trauma with very high accuracy, enabling faster ...

  16. Abdominal ultrasound (image)

    Science.gov (United States)

    Abdominal ultrasound is a scanning technique used to image the interior of the abdomen. Like the X-ray, MRI, ... it has its place as a diagnostic tool. Ultrasound scans use high frequency sound waves to produce ...

  17. What Are the Signs, Symptoms, and Complications of High Blood Pressure?

    Science.gov (United States)

    ... What Are the Signs, Symptoms, and Complications of High Blood Pressure? Because diagnosis is based on blood pressure readings, ... damaged from chronic high blood pressure. Complications of High Blood Pressure When blood pressure stays high over time, it ...

  18. Modeling, Parameters Identification, and Control of High Pressure Fuel Cell Back-Pressure Valve

    Directory of Open Access Journals (Sweden)

    Fengxiang Chen

    2014-01-01

    Full Text Available The reactant pressure is crucial to the efficiency and lifespan of a high pressure PEMFC engine. This paper analyses a regulated back-pressure valve (BPV for the cathode outlet flow in a high pressure PEMFC engine, which can achieve precisely pressure control. The modeling, parameters identification, and nonlinear controller design of a BPV system are considered. The identified parameters are used in designing active disturbance rejection controller (ADRC. Simulations and extensive experiments are conducted with the xPC Target and show that the proposed controller can not only achieve good dynamic and static performance but also have strong robustness against parameters’ disturbance and external disturbance.

  19. Outcome of intraoperative goal-directed therapy using Vigileo/FloTrac in high-risk patients scheduled for major abdominal surgeries: A prospective randomized trial

    Directory of Open Access Journals (Sweden)

    Mohammed A. Elgendy

    2017-07-01

    Conclusion: The applied protocol for intraoperative GDT provided significant reduction of PO morbidities, ICU and hospital LOS but couldn‘t significantly reduce mortality rates in high risk patients scheduled for major abdominal surgeries.

  20. The administration of long-term high-fat diet in ovariectomized wistar rat (Study on Daily Food Intake, Lee Index, Abdominal Fat Mass and Leptin Serum Levels

    Directory of Open Access Journals (Sweden)

    Dita Fitriani

    2016-12-01

    Conclusion: Serum leptin levels positively correlated with Lee index and abdominal fat mass, but negatively correlated with daily food intake. Administration of long-term high-fat diet in this study cannot induce leptin resistance.

  1. Prevalence of risk factors, coronary and systemic atherosclerosis in abdominal aortic aneurysm: Comparison with high cardiovascular risk population

    Directory of Open Access Journals (Sweden)

    Alberto Palazzuoli

    2008-08-01

    Full Text Available Alberto Palazzuoli, Maddalena Gallotta, Giuseppe Guerrieri, Ilaria Quatrini, Beatrice Franci, et alDepartment of Internal Medicine and Metabolic Diseases, Unit of Aortic Surgery, University of Siena, ItalyBackground: Abdominal aortic aneurysm (AAA is considered a manifestation of atherosclerosis, however there are epidemiologic, biochemical, and structural differences between occlusive atherosclerosis and AAA. The pathogenesis of AAA involves several factors, first of all destruction of collagen and elastin in the aortic wall. Classical risk factors may influence the evolution and development of AAA, though no consistent association has been found. Aims of the study were to evaluate associations between risk factors and to establish the prevalence of carotid, peripheral vascular and coronary atherosclerosis in patients with AAA.Methods: We studied 98 patients with AAA (Group 1 awaiting surgery compared with high cardiovascular risk population having two or more risk factors (n = 82 Group 2. We evaluated traditional risk factors and we studied by eco-doppler and echocardiography the presence of carotid peripheral and coronaric atherosclerosis in two groups.Results: We found a higher incidence of AAA in males (p < 0.01. The prevalence of infrarenal AAA was significantly higher than suprarenal AAA (81 vs 17 p < 0.001. No differences in total cholesterol (199 ± 20 vs. 197 ± 25 mg/dl, low-density lipoprotein (142 ± 16 vs. 140 ± 18 mg/dl, triglycerides (138 ± 45 vs. 144 ± 56 mg/dl, glycemia (119 ± 15 vs. 122 ± 20 mg/dl, and fibrinogen (388 ± 154 vs. 362 ± 92 mg/dl were found between groups. We demonstrated significant differences for cigarette smoking (p < 0.002, systolic and diastolic blood pressure (150 ± 15 vs. 143 ± 14 mmHg and 88 ± 6 vs. 85 ± 7 mmHg, p < 0.0001 and p < 0.05, respectively and high sensititivity C reactive protein (2.8 ± 1.3 vs. 1.3 ± 0.7 mg/dl, p < 0.001. High-density lipoprotein (HDL cholesterol levels were

  2. Randomized Trial of Low-pressure Carbon Dioxide-elicited Pneumoperitoneum Versus Abdominal Wall Lifting for Laparoscopic Cholecystectomy

    Directory of Open Access Journals (Sweden)

    Yih-Huei Uen

    2007-08-01

    Conclusion: Both alternative methods for this type of surgery appeared feasible and safe for LC. Low-pressure CO2 pneumoperitoneum had a shorter surgical duration and less postoperative shoulder pain compared to the GLC technique, but did not feature any other advantage over the AWL technique with regard to impact on cardiopulmonary function.

  3. High Pressure, High Gradient RF Cavities for Muon Beam Cooling

    CERN Document Server

    Johnson, R P

    2004-01-01

    High intensity, low emittance muon beams are needed for new applications such as muon colliders and neutrino factories based on muon storage rings. Ionization cooling, where muon energy is lost in a low-Z absorber and only the longitudinal component is regenerated using RF cavities, is presently the only known cooling technique that is fast enough to be effective in the short muon lifetime. RF cavities filled with high-pressure hydrogen gas bring two advantages to the ionization technique: the energy absorption and energy regeneration happen simultaneously rather than sequentially, and higher RF gradients and better cavity breakdown behavior are possible than in vacuum due to the Paschen effect. These advantages and some disadvantages and risks will be discussed along with a description of the present and desired RF R&D efforts needed to make accelerators and colliders based on muon beams less futuristic.

  4. High pressure/high temperature thermogravimetric apparatus. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Calo, J.M.; Suuberg, E.M.

    1999-12-01

    The purpose of this instrumentation grant was to acquire a state-of-the-art, high pressure, high temperature thermogravimetric apparatus (HP/HT TGA) system for the study of the interactions between gases and carbonaceous solids for the purpose of solving problems related to coal utilization and applications of carbon materials. The instrument that we identified for this purpose was manufactured by DMT (Deutsche Montan Technologies)--Institute of Cokemaking and Coal Chemistry of Essen, Germany. Particular features of note include: Two reactors: a standard TGA reactor, capable of 1100 C at 100 bar; and a high temperature (HT) reactor, capable of operation at 1600 C and 100 bar; A steam generator capable of generating steam to 100 bar; Flow controllers and gas mixing system for up to three reaction gases, plus a separate circuit for steam, and another for purge gas; and An automated software system for data acquisition and control. The HP/TP DMT-TGA apparatus was purchased in 1996 and installed and commissioned during the summer of 1996. The apparatus was located in Room 128 of the Prince Engineering Building at Brown University. A hydrogen alarm and vent system were added for safety considerations. The system has been interfaced to an Ametek quadruple mass spectrometer (MA 100), pumped by a Varian V250 turbomolecular pump, as provided for in the original proposed. With this capability, a number of gas phase species of interest can be monitored in a near-simultaneous fashion. The MS can be used in a few different modes. During high pressure, steady-state gasification experiments, it is used to sample, measure, and monitor the reactant/product gases. It can also be used to monitor gas phase species during nonisothermal temperature programmed reaction (TPR) or temperature programmed desorption (TPD) experiments.

  5. High pressure and anesthesia: pressure stimulates or inhibits bacterial bioluminescence depending upon temperature.

    Science.gov (United States)

    Nosaka, S; Kamaya, H; Ueda, I

    1988-10-01

    Although high pressure is often viewed as a nonspecific stimulus counteracting anesthesia, pressure can either excite or inhibit biological activity depending on the temperature at application. Temperature and pressure are two independent variables that determine equilibrium quantity, e.g., the state of organisms in terms of activity and anesthesia depth. We used the light intensity of luminous bacteria (Vibrio fischeri) as an activity parameter, and studied the effects of pressure and anesthetics on the bacteria's light intensity at various temperatures. The light intensity was greatest at about 30 degrees C at ambient pressure. When the system was pressurized up to 204 atm, the temperature for maximum light intensity was shifted to higher temperatures. Above the optimal temperature for the maximal light intensity, high pressure increased the light intensity. Below the optimal temperature, pressure decreased light intensity. Pressure only shifts the reaction equilibrium to the lower volume state (Le Chatelier's principle). When the volume of the excited state is larger than the resting state, high pressure inhibits excitation, and vice versa. Halothane 0.008 atm and isoflurane 0.021 atm inhibited the light intensity both above and below the optimal temperature. When pressurized, the light intensity increased in the high temperature range but decreased in the low temperature range, as in the control. Thus, high pressure seemingly potentiated the anesthetic action at low temperatures. When the ratio of the light intensity in bacteria exposed to anesthesia and those not exposed to anesthesia was plotted against the pressure, however, the value approached unity in proportion to the pressure increase.(ABSTRACT TRUNCATED AT 250 WORDS)

  6. Elastic properties of solids at high pressure

    Science.gov (United States)

    Vekilov, Yu Kh; Krasilnikov, O. M.; Lugovskoy, A. V.

    2015-11-01

    This review examines the elastic response of solids under load. The definitions of isothermal and adiabatic elastic constants of ( n≥2) for a loaded crystal are given. For the case of hydrostatic pressure, two techniques are proposed for calculating the second-, third-, and fourth-order elastic constants from the energy-strain and stress-strain relations. As an example, using the proposed approach within the framework of the density functional theory, the second- to fourth-order elastic constants of bcc tungsten are calculated for the pressure range of 0-600 GPa.

  7. Study on Manganin High Pressure Array Sensor

    Institute of Scientific and Technical Information of China (English)

    DUAN Jianhua; DU Xiaosong; YANG Bangchao; ZHOU Hongre

    2003-01-01

    A new kind of thin film manganin aray gauge is fabricated by adopting a new sensor fabrication technique. The sensitive materials (manganin thin films) are first deposited by magnetron sputtering on fused silica substrates, and then covered by a layer of SiO2 thin films by electron beam evaporation. Based on impedance match method of "back configuration", the highest pressure measured in Al target is 51.68 Gpa, the highest pressure in SiO2 package is 35.396 Gpa and the piezoresistance coefficient k is 0.026 Gpa-1. The upper limit and measure precision of sensor is improved.

  8. Announcement: National High Blood Pressure Education Month - May 2016.

    Science.gov (United States)

    2016-05-27

    May is National High Blood Pressure Education Month. High blood pressure (hypertension) is a major contributor to heart disease and stroke, two leading causes of death in the United States.* High blood pressure affects one third of U.S. adults, or approximately 75 million persons, yet approximately 11 million of these persons are not aware they have hypertension, and approximately 18 million are not being treated (unpublished data) (1,2).

  9. High-pressure magic angle spinning nuclear magnetic resonance

    Science.gov (United States)

    Hoyt, David W.; Turcu, Romulus V. F.; Sears, Jesse A.; Rosso, Kevin M.; Burton, Sarah D.; Felmy, Andrew R.; Hu, Jian Zhi

    2011-10-01

    A high-pressure magic angle spinning (MAS) NMR capability, consisting of a reusable high-pressure MAS rotor, a high-pressure rotor loading/reaction chamber for in situ sealing and re-opening of the high-pressure MAS rotor, and a MAS probe with a localized RF coil for background signal suppression, is reported. The unusual technical challenges associated with development of a reusable high-pressure MAS rotor are addressed in part by modifying standard ceramics for the rotor sleeve by abrading the internal surface at both ends of the cylinder. In this way, not only is the advantage of ceramic cylinders for withstanding very high-pressure utilized, but also plastic bushings can be glued tightly in place so that other removable plastic sealing mechanisms/components and O-rings can be mounted to create the desired high-pressure seal. Using this strategy, sealed internal pressures exceeding 150 bars have been achieved and sustained under ambient external pressure with minimal loss of pressure for 72 h. As an application example, in situ13C MAS NMR studies of mineral carbonation reaction intermediates and final products of forsterite (Mg 2SiO 4) reacted with supercritical CO 2 and H 2O at 150 bar and 50 °C are reported, with relevance to geological sequestration of carbon dioxide.

  10. High-pressure magic angle spinning nuclear magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Hoyt, David W.; Turcu, Romulus V. F.; Sears, Jesse A.; Rosso, Kevin M.; Burton, Sarah D.; Felmy, Andrew R.; Hu, Jian Zhi

    2011-10-01

    A high-pressure magic angle spinning (MAS) NMR capability, consisting of a reusable high-pressure MAS rotor, a high-pressure rotor loading/reaction chamber for in situ sealing and re-opening of the high-pressure MAS rotor, and a MAS probe with a localized RF coil for background signal suppression, is reported. The unusual technical challenges associated with development of a reusable high-pressure MAS rotor are addressed in part by modifying standard ceramics for the rotor sleeve by abrading the internal surface at both ends of the cylinder. In this way, not only is the advantage of ceramic cylinders for withstanding very high-pressure utilized, but also plastic bushings can be glued tightly in place so that other removable plastic sealing mechanisms/components and O-rings can be mounted to create the desired high-pressure seal. Using this strategy, sealed internal pressures exceeding 150 bars have been achieved and sustained under ambient external pressure with minimal loss of pressure for 72 h. Finally, as an application example, in situ13C MAS NMR studies of mineral carbonation reaction intermediates and final products of forsterite (Mg2SiO4) reacted with supercritical CO2 and H2O at 150 bar and 50 °C are reported, with relevance to geological sequestration of carbon dioxide.

  11. Vibrational spectroscopy at high external pressures the diamond anvil cell

    CERN Document Server

    Ferraro, John R

    1984-01-01

    Vibrational Spectroscopy at High External Pressures: The Diamond Anvil Cell presents the effects of high pressure on the vibrational properties of materials as accomplished in a diamond anvil cell (DAC). The DAC serves the dual purpose of generating the pressures and being transparent to infrared radiation, allowing the observation of changes caused by pressure. The optical probes highlighted will deal principally with infrared and Raman scattering, although some observations in the visible region will also be presented. The book begins with a discussion of the effects of pressure and pres

  12. Surveillance of intra-abdominal pressure and intestinal barrier function in a rat model of acute necrotizing pancreatitis and its potential early therapeutic window.

    Directory of Open Access Journals (Sweden)

    Wei-Dong Li

    Full Text Available OBJECTIVES: To monitor intra-abdominal pressure (IAP and intestinal barrier function in a rat model of acute necrotizing pancreatitis (ANP to elucidate a potential relevant therapeutic window. METHODS: Sprague-Dawley rats were randomly divided into experimental or control groups. The ANP group (n = 40 was injected with 4.5% sodium taurocholate into the pancreatic duct to induce ANP. The controls received only abdominal opening surgery (sham-operated, SO; n = 40 or no treatment or surgery (baseline; 0 h, n = 20. The SO and ANP groups were then randomly subdivided into 3, 6, 12 and 24 h groups (n = 10 each. IAP was measured at each time point and the rats were sacrificed to measure the weight of accumulated ascites fluid and the amylase, endogenous creatinine (Cr, total bilirubin (TB, tumor necrosis factor- alpha (TNF-alpha, diamine oxidase (DAO, and D-lactate. Mortality and the development of pathological changes in the pancreas and intestines were also monitored. RESULTS: IAP showed a continuous upward trend in the ANP group, with values 2 to 3 times higher than those in the SO group at the corresponding time points and the rising rate was peaking at 6 h. The levels of plasma amylase, TNF-alpha, Cr, TB, DAO, and D-lactate also gradually increased in the ANP group over time and were significantly higher than in the SO group at 3, 6, 12 and 24 h (all P<0.05. Moreover, the rising rate of TNF-alpha, DAO, and D-lactate also peaked at 6 h. CONCLUSIONS: The ANP-induced changes in IAP, inflammatory factors and intestinal barrier that we observed in the rat model were especially obvious at 6 h post-induction, suggesting an early therapeutic window for the treatment of ANP in humans.

  13. Ultrasonic Propagation in Liquids Under High Pressures

    Science.gov (United States)

    1948-12-01

    34 Proc. Am, Acad. Arts Sci. 19, 143 (1923). 28. Bridgman P. W., "The Viscosity of Liquids under Pressure," Proc. Nat. Acad. Sci. 119 603 (1925). TM3...1932). 42. Ewell, R. H., and Eyring, H., "Theory of the Viscosity of Liquids as a Function of Temperature and Pressureg" J. Chem. Phys. 1, 726 (1937

  14. Nanocomposite Thermolectric Materials by High Pressure Powder Consolidation Manufacturing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In response to NASA's need to develop advanced nanostructured thermolectric materials, UTRON is proposing an innovative high pressure powder consolidation...

  15. Nanocomposite Thermolectric Materials by High Pressure Powder Consolidation Manufacturing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In response to NASA's need to develop advanced nanostructured thermolectric materials, UTRON is proposing an innovative high pressure powder consolidation...

  16. A system for incubations at high gas partial pressure

    DEFF Research Database (Denmark)

    Sauer, Patrick; Glombitza, Clemens; Kallmeyer, Jens

    2012-01-01

    High-pressure is a key feature of deep subsurface environments. High partial pressure of dissolved gasses plays an important role in microbial metabolism, because thermodynamic feasibility of many reactions depends on the concentration of reactants. For gases, this is controlled by their partial...... pressure, which can exceed 1 MPa at in situ conditions. Therefore, high hydrostatic pressure alone is not sufficient to recreate true deep subsurface in situ conditions, but the partial pressure of dissolved gasses has to be controlled as well. We developed an incubation system that allows for incubations...... and inert PVDF (polyvinylidene fluoride) incubator sleeve, which is almost impermeable for gases, holds the sample and separates it from the pressure fluid. The flexibility of the incubator sleeve allows for sub-sampling of the medium without loss of pressure. Experiments can be run in both static and flow...

  17. Abdominal pain

    Science.gov (United States)

    Stomach pain; Pain - abdomen; Belly ache; Abdominal cramps; Bellyache; Stomachache ... Almost everyone has pain in the abdomen at some point. Most of the time, it is not serious. How bad your pain is does not always reflect the seriousness ...

  18. Abdominal actinomycosis.

    Science.gov (United States)

    Wagenlehner, F M E; Mohren, B; Naber, K G; Männl, H F K

    2003-08-01

    Intra-abdominal and extraperitoneal actinomycosis are rare infections, caused by different Actinomyces species. However, they have been diagnosed more frequently in the last ten years. We report three cases of abdominal actinomycosis and a literature review of the last eight years. All three patients were diagnosed by means of histopathologic examination only. In one case, an intrauterine device (IUD) was associated with the infection. Therapy consisted of surgical resection of the inflammatory, infected tissue, and long-term antibiotic therapy. All patients are free of recurrence. Abdominal actinomycosis should be included in the differential diagnosis of an abdominal pathology of insidious onset, especially when an IUD is in place. Even when infection had spread extensively, combined operative and antibiotic therapy cured most of the cases.

  19. Abdominal tuberculosis: Imaging features

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Jose M. [Department of Radiology, Hospital de S. Joao, Porto (Portugal)]. E-mail: jmpjesus@yahoo.com; Madureira, Antonio J. [Department of Radiology, Hospital de S. Joao, Porto (Portugal); Vieira, Alberto [Department of Radiology, Hospital de S. Joao, Porto (Portugal); Ramos, Isabel [Department of Radiology, Hospital de S. Joao, Porto (Portugal)

    2005-08-01

    Radiological findings of abdominal tuberculosis can mimic those of many different diseases. A high level of suspicion is required, especially in high-risk population. In this article, we will describe barium studies, ultrasound (US) and computed tomography (CT) findings of abdominal tuberculosis (TB), with emphasis in the latest. We will illustrate CT findings that can help in the diagnosis of abdominal tuberculosis and describe imaging features that differentiate it from other inflammatory and neoplastic diseases, particularly lymphoma and Crohn's disease. As tuberculosis can affect any organ in the abdomen, emphasis is placed to ileocecal involvement, lymphadenopathy, peritonitis and solid organ disease (liver, spleen and pancreas). A positive culture or hystologic analysis of biopsy is still required in many patients for definitive diagnosis. Learning objectives:1.To review the relevant pathophysiology of abdominal tuberculosis. 2.Illustrate CT findings that can help in the diagnosis.

  20. Blood pressure in childhood : epidemiological probes into the aetiology of high blood pressure

    NARCIS (Netherlands)

    A. Hofman (Albert)

    1983-01-01

    textabstractHigh arterial blood pressure takes a heavy toll in western populations (1 ). Its causes are still largely unknown, but its sequelae, a variety of cardiovascular and renal diseases, have been referred to as "a modern scourge" (2). High blood pressure of unknown cause, or essential hyperte

  1. Blood pressure in childhood : epidemiological probes into the aetiology of high blood pressure

    NARCIS (Netherlands)

    A. Hofman (Albert)

    1983-01-01

    textabstractHigh arterial blood pressure takes a heavy toll in western populations (1 ). Its causes are still largely unknown, but its sequelae, a variety of cardiovascular and renal diseases, have been referred to as "a modern scourge" (2). High blood pressure of unknown cause, or

  2. [Genesis study of omphacite at high pressure and high temperature].

    Science.gov (United States)

    Xiao, Ben-Fu; Yi, Li; Wang, Duo-Jun; Xie, Chao; Tang, Xue-Wu; Liu, Lei; Cui, Yue-Ju

    2013-11-01

    The melting and recrystallizing experiments of alkali basalt powder and mixture of pure oxides mixed as stoichiometry were performed at 3 GPa and 1 200 degrees C. Electronic microprobe analysis and Raman spectra showed that the recrystallized products were omphacites, the FWHM (full width at half maximum) of the Raman peak was narrow and its shape was sharp, which is attributed to the stable Si-O tetrahedral structure and the high degree of order in omphacite. Based on the results of previous studies, the influencing factors of omphacite genesis and its primary magma were discussed. The results showed that the formation of omphacite could be affected by many factors, such as the composition of parent rocks, the concentration of fluid in the system and the conditions of pressure and temperature. This result could support some experimental evidences on the genesis studies of omphacite and eclogite.

  3. High Pressure Cryocooling of Protein Crystals: The Enigma of Water

    Science.gov (United States)

    Gruner, Sol M.

    2010-03-01

    A novel high-pressure cryocooling technique for preparation biological samples for x-ray analysis is described. The method, high-pressure cryocooling, involves cooling samples to cryogenic temperatures (e.g., 100 K) in high-pressure Helium gas (up to 200 MPa). It bears both similarities and differences to high-pressure cooling methods that have been used to prepare samples for electron microscopy, and has been especially useful for cryocooling of macromolecular crystals for x-ray diffraction. Examples will be given where the method has been effective in providing high quality crystallographic data for difficult samples, such as cases where ligands needed to be stabilized in binding sites to be visualized, or where very high resolution data were required. The talk concludes with a discussion of data obtained by high-pressure cryocooling that pertains to two of the most important problems in modern science: the enigma of water and how water affects the activity of proteins.

  4. Dirty Air, High Blood Pressure Linked

    Institute of Scientific and Technical Information of China (English)

    应树道

    2001-01-01

    贵刊去年第6期曾刊登一短文,题目是:盐,迫升血压之元凶。读了该文,我开始严格控制每日的食盐摄入量,再附以药物治疗,血压果然趋于平稳。近日上网,遇一奇文,意思是人的血压与空气污染状况有涉!根据对2600个成年人的调查,得出了这样的结论:Pollution may cause changes in the part of the nervous system that controls blood pressure.文章又同时说明:Exactly how pollution might cause blood pressure to climb remains unclear.人体之奥妙由此可见一斑。

  5. Low Pressure Evidence of High Pressure Shock: Thermal Histories and Annealing in Shocked Meteorites

    Science.gov (United States)

    Sharp, T. G.; Hu, J.

    2016-08-01

    In this study we look at the mineralogy associated with shock veins in several highly shocked L chondrites to better understand shock conditions and the importance of thermal history in creating and destroying high-pressure minerals.

  6. Recent progress in high pressure metrology in Europe

    Directory of Open Access Journals (Sweden)

    Sabuga Wladimir

    2014-01-01

    Full Text Available Five European national metrology institutes in collaboration with a university, a research institute and five industrial companies are working on a joint research project within a framework of the European Metrology Research Programme aimed at development of 1.6 GPa primary and 1.5 GPa transfer pressure standards. Two primary pressure standards were realised as pressure-measuring multipliers, each consisting of a low pressure and a high pressure (HP piston-cylinder assembly (PCA. A special design of the HP PCAs was developed in which a tungsten carbide cylinder is supported by two thermally shrunk steel sleeves and, additionally, by jacket pressure applied to the outside of the outer sleeve. Stress-strain finite element analysis (FEA was performed to predict behaviour of the multipliers and a pressure generation system. With FEA, the pressure distortion coefficient was determined, taking into account irregularities of the piston-cylinder gap. Transfer pressure standards up to 1.5 GPa are developed on the basis of modern 1.5 GPa pressure transducers. This project shall solve a discrepancy between the growing needs of the industry demanding precise traceable calibrations of the high pressure transducers and the absence of adequate primary standards for pressures higher than 1 GPa in the European Union today.

  7. The electrical resistance of PuSb under high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Link, P. (European Commission, Joint Research Centre, Institute for Transuranium Elements, Postfach 2340, D76125 Karlsruhe (Germany)); Benedict, U. (European Commission, Joint Research Centre, Institute for Transuranium Elements, Postfach 2340, D76125 Karlsruhe (Germany)); Wittig, J. (Institut fuer Festkoerperforschung, Forschungszentrum Juelich, D52425 Juelich (Germany)); Wuehl, H. (Institut fuer Experimentelle Kernphysik, Universitaet Karlsruhe, D76128 Karlsruhe (Germany)); Rebizant, J. (European Commission, Joint Research Centre, Institute for Transuranium Elements, Postfach 2340, D76125 Karlsruhe (Germany)); Spirlet, J.C. (European Commission, Joint Research Centre, Institute for Transuranium Elements, Postfach 2340, D76125 Karlsruhe (Germany))

    1994-10-01

    A new experimental set-up with a Bridgman-type high pressure cell in a closed containment allows resistance measurements on highly radioactive materials. We present results of high pressure, low temperature studies on PuSb single crystals in the pressure range to 25 GPa and at temperatures between 1.3 K and 300 K. As pressure on PuSb is increased, its Neel temperature and the transition temperature to the ferromagnetic ground state are increased. In the pressure range from 10 to 15 GPa, we observed a strong decrease in the resistance associated with the crystallographic phase transition from the B1 (NaCl) to the B2 (CsCl) structure. The high pressure phase appears to be non-magnetic. ((orig.))

  8. High-pressure behavior of superconducting boron-doped diamond

    Science.gov (United States)

    Abdel-Hafiez, Mahmoud; Kumar, Dinesh; Thiyagarajan, R.; Zhang, Q.; Howie, R. T.; Sethupathi, K.; Volkova, O.; Vasiliev, A.; Yang, W.; Mao, H. K.; Rao, M. S. Ramachandra

    2017-05-01

    This work investigates the high-pressure structure of freestanding superconducting (Tc=4.3 K) boron-doped diamond (BDD) and how it affects the electronic and vibrational properties using Raman spectroscopy and x-ray diffraction in the 0-30 GPa range. High-pressure Raman scattering experiments revealed an abrupt change in the linear pressure coefficients, and the grain boundary components undergo an irreversible phase change at 14 GPa. We show that the blueshift in the pressure-dependent vibrational modes correlates with the negative pressure coefficient of Tc in BDD. The analysis of x-ray diffraction data determines the equation of state of the BDD film, revealing a high bulk modulus of B0=510 ±28 GPa. The comparative analysis of high-pressure data clarified that the s p2 carbons in the grain boundaries transform into hexagonal diamond.

  9. High-pressure hollow cathode discharges

    Science.gov (United States)

    Schoenbach, Karl H.; El-Habachi, Ahmed; Shi, Wenhui; Ciocca, Marco

    1997-11-01

    Reducing the diameter of the cathode hole in a plane anode - hollow cathode geometry to 0963-0252/6/4/003/img1m has allowed us to generate direct current discharges in argon at atmospheric pressure. Up to pressure times cathode hole diameter (pD) values of approximately 5 Torr cm, and at sub-mA currents, glow discharges (predischarges) are observed with a shape which is determined by the vacuum electric field. In the same pD range, but at higher currents of up to approximately 4 mA, the discharges are of the hollow cathode discharge type. At pD values exceeding 5 Torr cm the predischarges turn into surface discharges along the mica spacer between the electrodes. At currents > 4 mA filamentary, pulsed discharges are observed. Qualitative information on the electron energy distribution in the microdischarges has been obtained by studying the VUV emission from ionized argon atoms and the argon excimer radiation at 130 nm. The results of the spectral measurements indicate the presence of a relatively large concentration of electrons with energies > 15 eV over the entire pressure range. The fact that the current - voltage characteristic of the microdischarges has a positive slope over much of the current range where excimer radiation is emitted indicates the possibility of forming arrays of these discharges and using them in flat panel excimer lamps.

  10. Raman spectroscopy on carbon nanotubes at high pressure

    OpenAIRE

    Loa, I.

    2003-01-01

    Raman spectroscopy has been the most extensively employed method to study carbon nanotubes at high pressures. This review covers reversible pressure-induced changes of the lattice dynamics and structure of single- and multi-wall carbon nanotubes as well as irreversible transformations induced by high pressures. The interplay of covalent and van-der-Waals bonding in single-wall nanotube bundles and a structural distortion near 2 GPa are discussed in detail. Attempts of transforming carbon nano...

  11. Dynamic High-Pressure Behavior of Hierarchical Heterogeneous Geological Materials

    Science.gov (United States)

    2016-04-01

    pressure -density Hugoniot plots for simulations using the ‘mix 5’ option, as will be presented later. The volume weighted option for mixed cells (refered...AFRL-AFOSR-VA-TR-2016-0150 Dynamic High- Pressure Behavior of Geological Materials Naresh Thadhani GEORGIA TECH RESEARCH CORPORATION Final Report 04...31-12-2015 4.  TITLE AND SUBTITLE Dynamic High- Pressure Behavior of Hierarchical Heterogeneous Geological Materials 5a.  CONTRACT NUMBER 5b.  GRANT

  12. Structural behaviour of niobium oxynitride under high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Bharat Bhooshan, E-mail: bbs86phy@gmail.com; Poswal, H. K., E-mail: bbs86phy@gmail.com; Pandey, K. K., E-mail: bbs86phy@gmail.com; Sharma, Surinder M., E-mail: bbs86phy@gmail.com [High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Center, Mumbai-400085 (India); Yakhmi, J. V. [Homi Bhabha National Institute, Mumbai - 400094 (India); Ohashi, Y.; Kikkawa, S. [Faculty of Engineering, Hokkaido University, N13W8, Sapporo 080-8628 (Japan)

    2014-04-24

    High pressure investigation of niobium oxynitrides (NbN{sub 0.98}O{sub 0.02}) employing synchrotron based angle dispersive x-ray diffraction experiments was carried out in very fine pressure steps using membrane driven diamond anvil cell. Ambient cubic phase was found to be stable up to ∼18 GPa. At further high pressure cubic phase showed rhombohedral distortion.

  13. Complete abdominal aortic aneurysm thrombosis and obstruction of both common iliac arteries with intrathrombotic pressures demonstrating a continuing risk of rupture: a case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Kotzadimitriou Aikaterini

    2009-01-01

    Full Text Available Abstract Introduction Although mural thrombus in an abdominal aortic aneurysm is frequent and its role has been studied extensively, complete thrombosis of an abdominal aneurysm is extremely rare and its natural history in relation to the risk of rupture is not known. The case of a patient with a completely thrombosed infrarenal aneurysm is presented along with a literature review. Case presentation We report the case of a 56-year-old Caucasian man with an infrarenal abdominal aortic aneurysm, presenting at our hospital due to critical ischemia of his right lower limb. Computed tomography and angiography demonstrated complete aneurysm thrombosis and obstruction of both common iliac arteries. Conclusion During the operation, systolic and mean intrathrombotic pressures, measured in different levels, constituted 74.5-90.2% and 77.5-92.5% of systolic and mean intraluminal pressure and 73-88.4% and 76.5-91.3% of systemic pressure, respectively. Our findings show that there may be a continuing risk of rupture in cases of a thrombosed abdominal aortic aneurysm.

  14. [Examination of upper abdominal region in high spatial resolution diffusion-weighted imaging using 3-Tesla MRI].

    Science.gov (United States)

    Terada, Masaki; Matsushita, Hiroki; Oosugi, Masanori; Inoue, Kazuyasu; Yaegashi, Taku; Anma, Takeshi

    2009-03-20

    The advantage of the higher signal-to-noise ratio (SNR) of 3-Tesla magnetic resonance imaging (3-Tesla) has the possibility of contributing to the improvement of high spatial resolution without causing image deterioration. In this study, we compared SNR and the apparent diffusion coefficient (ADC) value with 3-Tesla as the condition in the diffusion-weighted image (DWI) parameter of the 1.5-Tesla magnetic resonance imaging (1.5-Tesla) and we examined the high spatial resolution images in the imaging method [respiratory-triggering (RT) method and breath free (BF) method] and artifact (motion and zebra) in the upper abdominal region of DWI at 3-Tesla. We have optimized scan parameters based on phantom and in vivo study. As a result, 3-Tesla was able to obtain about 1.5 times SNR in comparison with the 1.5-Tesla, ADC value had few differences. Moreover, the RT method was effective in correcting the influence of respiratory movement in comparison with the BF method, and image improvement by the effective acquisition of SNR and reduction of the artifact were provided. Thus, DWI of upper abdominal region was a useful sequence for the high spatial resolution in 3-Tesla.

  15. The association between cardiovascular risk factors and high blood pressure in adolescents: a school-based study.

    Science.gov (United States)

    Christofaro, Diego G D; Fernandes, Rômulo A; Oliveira, Arli R; Freitas Júnior, Ismael Forte; Barros, Mauro V G; Ritti-Dias, Raphael M

    2014-01-01

    Although previous studies have analyzed the association between cardiovascular risk factors and blood pressure in adolescents, few studies conducted in developing countries analyzed whether the aggregation of risk factors contributes to an increased risk of high blood pressure in adolescents. The objective of this study was to assess the association between cardiovascular risk factors (including general overweight, abdominal obesity, high consumption of foods rich in fats, and insufficient physical activity levels) and high blood pressure in adolescents. This study was carried out from 2007 to 2008 with 1021 adolescents (528 girls) from primary schools located in the city of Londrina- Brazil. Blood pressure was assessed using an oscillometric device. General overweight was obtained through body mass index, abdominal obesity was assessed using waist circumference, and the consumption of foods rich in fat and physical activity were assessed using a questionnaire. The sum of these risk factors was determined. Adolescents with three or four aggregated risk factors were more likely to have higher values of systolic and diastolic blood pressure when compared with adolescents who did not have any cardiovascular risk factors (P = 0.001 for both). Logistic regression indicated that groups of adolescents with 2 (OR= 2.46 [1.11-5.42]; P = 0.026), 3 (OR= 4.97 [2.07-11.92]; P = 0.001) or 4 risk factors (OR= 6.79 [2.24-19.9]; P = 0.001) presented an increased likelihood of high blood pressure. The number of cardiovascular risk factors was found to be related to high blood pressure in adolescents. Copyright © 2014 Wiley Periodicals, Inc.

  16. High-pressure effects on intramolecular electron transfer compounds

    CERN Document Server

    He Li Ming; Li Hong; Zhang Bao Wen; Li Yi; Yang Guo Qiang

    2002-01-01

    We explore the effect of pressure on the fluorescence spectra of the intramolecular electron transfer compound N-(1-pyrenylmethyl), N-methyl-4-methoxyaniline (Py-Am) and its model version, with poly(methyl methacrylate) blended in, at high pressure up to 7 GPa. The emission properties of Py-Am and pyrene show distinct difference with the increase of pressure. This difference indicates the strength of the charge transfer interaction resulting from the adjusting of the conformation of Py-Am with increase of pressure. The relationship between the electronic state of the molecule and pressure is discussed.

  17. Cells under pressure - treatment of eukaryotic cells with high hydrostatic pressure, from physiologic aspects to pressure induced cell death.

    Science.gov (United States)

    Frey, Benjamin; Janko, Christina; Ebel, Nina; Meister, Silke; Schlücker, Eberhard; Meyer-Pittroff, Roland; Fietkau, Rainer; Herrmann, Martin; Gaipl, Udo S

    2008-01-01

    The research on high hydrostatic pressure in medicine and life sciences is multifaceted. According to the used pressure head the research has to be divided into two different parts. To study physiological aspects of pressure on eukaryotic cells physiological pressure (pHHP; highly reversible alterations and normally does not affect cellular viability. The treatment of eukaryotic cells with non-physiological pressure (HHP; > or = 100 MPa) reveals different outcomes. Treatment with HHP or = 200 MPa. Moreover, HHP treatment with > 300 MPa leads to necrosis. Therefore, HHP plays a role for the sterilisation of human transplants, of food stuff, and pharmaceuticals. Human tumour cells subjected to HHP > 300 MPa display a necrotic phenotype along with a gelificated cytoplasm, preserve their shape, and retain their immunogenicity. These observations favour the use of HHP to produce whole cell based tumour vaccines. Further experiments revealed that the increment of pressure as well as the pressure holding time influences the cell death of tumour cells. We conclude that high hydrostatic pressure offers both, an economic, easy to apply, clean, and fast technique for the generation of vaccines, and a promising tool to study physiological aspects.

  18. High Blood Pressure, Afib and Your Risk of Stroke

    Science.gov (United States)

    ... atrial fibrillation has more than five times the risk of stroke.” “Because high blood pressure is so frequent, affecting tens of millions of ... is a more potent risk factor.” The two risk factors are also related to each other: High blood pressure is a risk factor for atrial fibrillation. Middle- ...

  19. Simple high-pressure cell for neutron scattering

    Science.gov (United States)

    Bao, Wei; Broholm, C.; Trevino, S. F.

    1995-02-01

    A high-pressure cell, capable of 8 kbar, is developed for neutron scattering. It can be used with ILL type orange cryostats to obtain a temperature as low as 1.5 K. The simple seal design described here can easily be adopted to other high-pressure applications.

  20. High-pressure processing for preservation of blood products

    NARCIS (Netherlands)

    Matser, A.M.; Ven, van der C.; Gouwerok, C.W.N.; Korte, de D.

    2005-01-01

    The possibilities of high pressure as a preservation method for human blood products were evaluated by examining the functional properties of blood fractions, after high-pressure processing at conditions which potentially inactivate micro-organisms and viruses. Blood platelets, red blood cells and

  1. 76 FR 38697 - High Pressure Steel Cylinders From China

    Science.gov (United States)

    2011-07-01

    ..., 2011 (76 FR 28807). The conference was held in Washington, DC, on June 1, 2011, and all persons who... COMMISSION High Pressure Steel Cylinders From China Determinations On the basis of the record \\1\\ developed... injured by reason of imports from China of high pressure steel cylinders, provided for in subheading...

  2. 77 FR 37712 - High Pressure Steel Cylinders From China

    Science.gov (United States)

    2012-06-22

    ... Commission, Washington, DC, and by publishing the notice in the Federal Register on January 23, 2012 (77 FR... COMMISSION High Pressure Steel Cylinders From China Determinations On the basis of the record \\1\\ developed... imports of high pressure steel cylinders from China, provided for in subheading 7311.00.00 of...

  3. What You Should Know About High Blood Pressure and Medications

    Science.gov (United States)

    ... Aortic Aneurysm More What You Should Know About High Blood Pressure and Medications Updated:Jan 18,2017 Is medication ... resources . This content was last reviewed October 2016. High Blood Pressure • Home • Get the Facts About HBP • Know Your ...

  4. Heart and Artery Damage and High Blood Pressure

    Science.gov (United States)

    ... Artery Disease Venous Thromboembolism Aortic Aneurysm More How High Blood Pressure Can Lead to a Heart Attack Updated:Dec ... sheet This content was last reviewed October 2016. High Blood Pressure • Home • Get the Facts About HBP • Know Your ...

  5. Americans with High Blood Pressure Still Eating Too Much Salt

    Science.gov (United States)

    ... medlineplus.gov/news/fullstory_163977.html Americans With High Blood Pressure Still Eating Too Much Salt Average sodium intake ... March 8, 2017 (HealthDay News) -- For Americans with high blood pressure, cutting back on salt is an important way ...

  6. Changes You Can Make to Manage High Blood Pressure

    Science.gov (United States)

    ... Aneurysm More Changes You Can Make to Manage High Blood Pressure Updated:Mar 10,2017 Fighting back against the “ ... Follow us on Twitter Follow us on Facebook High Blood Pressure • Home • Get the Facts About HBP • Know Your ...

  7. Strong environmental tolerance of Artemia under very high pressure

    Science.gov (United States)

    Minami, K.; Ono, F.; Mori, Y.; Takarabe, K.; Saigusa, M.; Matsushima, Y.; Saini, N. L.; Yamashita, M.

    2010-03-01

    It was shown by the present authors group that a tardigrade in its tun-state can survive after exposed to 7.5 GPa for 13 hours. We have extended this experiment to other tiny animals searching for lives under extreme conditions of high hydrostatic pressure. Artemia, a kind of planktons, in its dried egg-state have strong environmental tolerance. Dozens of Artemia eggs were sealed in a small Teflon capsule together with a liquid pressure medium, and exposed to the high hydrostatic pressure of 7.5 GPa. After the pressure was released, they were soaked in seawater to observe hatching rate. It was proved that 80-90% of the Artemia eggs were alive and hatched into Nauplii after exposed to the maximum pressure of 7.5 GPa for up to 48 hours. Comparing with Tardigrades, Artemia are four-times stronger against high pressure.

  8. Introduction to high-pressure bioscience and biotechnology.

    Science.gov (United States)

    Bartlett, Douglas H

    2010-02-01

    The manipulation of biological materials using elevated pressure is providing an ever-growing number of opportunities in both the applied and basic sciences. Manipulation of pressure is a useful parameter for enhancing food quality and shelf life; inactivating microbes, viruses, prions, and deleterious enzymes; affecting recombinant protein production; controlling DNA hybridization; and improving vaccine preparation. In biophysics and biochemistry, pressure is used as a tool to study intermediates in protein folding, enzyme kinetics, macromolecular interactions, amyloid fibrous protein aggregation, lipid structural changes, and to discern the role of solvation and void volumes in these processes. Biologists, including many microbiologists, examine the utility and basis of pressure inactivation of cells and cellular processes, and conversely seek to discover how deep-sea life has evolved a preference for high-pressure environments. This introduction and the papers that follow provide information on the nature and promise of the highly interdisciplinary field of high-pressure bioscience and biotechnology (HPBB).

  9. Pressurized metallurgy for high performance special steels and alloys

    Science.gov (United States)

    Jiang, Z. H.; Zhu, H. C.; Li, H. B.; Li, Y.; Liu, F. B.

    2016-07-01

    The pressure is one of the basic parameters which greatly influences the metallurgical reaction process and solidification of steels and alloys. In this paper the history and present situation of research and application of pressurized metallurgy, especially pressurized metallurgy for special steels and alloys have been briefly reviewed. In the following part the physical chemistry of pressurized metallurgy is summarized. It is shown that pressurizing may change the conditions of chemical reaction in thermodynamics and kinetics due to the pressure effect on gas volume, solubility of gas and volatile element in metal melt, activity or activity coefficient of components, and change the physical and chemical properties of metal melt, heat transfer coefficient between mould and ingot, thus greatly influencing phase transformation during the solidification process and the solidification structure, such as increasing the solidification nucleation rate, reducing the critical nucleation radius, accelerating the solidification speed and significant macro/micro-structure refinement, and eliminating shrinkage, porosity and segregation and other casting defects. In the third part the research works of pressured metallurgy performed by the Northeastern University including establishment of pressurized induction melting (PIM) and pressurized electroslag remelting (PESR) equipments and development of high nitrogen steels under pressure are described in detail. Finally, it is considered in the paper that application of pressurized metallurgy in manufacture of high performance special steels and alloys is a relatively new research area, and its application prospects will be very broad and bright.

  10. High-Pressure Oxygen Generation for Outpost EVA Study

    Science.gov (United States)

    Jeng, Frank F.; Conger, Bruce; Ewert, Michael K.; Anderson, Molly S.

    2009-01-01

    The amount of oxygen consumption for crew extravehicular activity (EVA) in future lunar exploration missions will be significant. Eight technologies to provide high pressure EVA O2 were investigated. They are: high pressure O2 storage, liquid oxygen (LOX) storage followed by vaporization, scavenging LOX from Lander followed by vaporization, LOX delivery followed by sorption compression, water electrolysis followed by compression, stand-alone high pressure water electrolyzer, Environmental Control and Life Support System (ECLSS) and Power Elements sharing a high pressure water electrolyzer, and ECLSS and In-Situ Resource Utilization (ISRU) Elements sharing a high pressure electrolyzer. A trade analysis was conducted comparing launch mass and equivalent system mass (ESM) of the eight technologies in open and closed ECLSS architectures. Technologies considered appropriate for the two architectures were selected and suggested for development.

  11. Impurity trapped excitons under high hydrostatic pressure

    Science.gov (United States)

    Grinberg, Marek

    2013-09-01

    Paper summarizes the results on pressure effect on energies of the 4fn → 4fn and 4fn-15d1 → 4fn transitions as well as influence of pressure on anomalous luminescence in Lnα+ doped oxides and fluorides. A model of impurity trapped exciton (ITE) was developed. Two types of ITE were considered. The first where a hole is localized at the Lnα+ ion (creation of Ln(α+1)+) and an electron is attracted by Coulomb potential at Rydberg-like states and the second where an electron captured at the Lnα+ ion (creation of Ln(α-1)+) and a hole is attracted by Coulomb potential at Rydberg-like states. Paper presents detailed analysis of nonlinear changes of energy of anomalous luminescence of BaxSr1-xF2:Eu2+ (x > 0.3) and LiBaF3:Eu2+, and relate them to ITE-4f65d1 states mixing.

  12. High-quality conforming hexahedral meshes of patient-specific abdominal aortic aneurysms including their intraluminal thrombi.

    Science.gov (United States)

    Tarjuelo-Gutierrez, J; Rodriguez-Vila, B; Pierce, D M; Fastl, T E; Verbrugghe, P; Fourneau, I; Maleux, G; Herijgers, P; Holzapfel, G A; Gomez, E J

    2014-02-01

    In order to perform finite element (FE) analyses of patient-specific abdominal aortic aneurysms, geometries derived from medical images must be meshed with suitable elements. We propose a semi-automatic method for generating conforming hexahedral meshes directly from contours segmented from medical images. Magnetic resonance images are generated using a protocol developed to give the abdominal aorta high contrast against the surrounding soft tissue. These data allow us to distinguish between the different structures of interest. We build novel quadrilateral meshes for each surface of the sectioned geometry and generate conforming hexahedral meshes by combining the quadrilateral meshes. The three-layered morphology of both the arterial wall and thrombus is incorporated using parameters determined from experiments. We demonstrate the quality of our patient-specific meshes using the element Scaled Jacobian. The method efficiently generates high-quality elements suitable for FE analysis, even in the bifurcation region of the aorta into the iliac arteries. For example, hexahedral meshes of up to 125,000 elements are generated in less than 130 s, with 94.8 % of elements well suited for FE analysis. We provide novel input for simulations by independently meshing both the arterial wall and intraluminal thrombus of the aneurysm, and their respective layered morphologies.

  13. Modulação da pressão intracraniana em um modelo experimental de hipertensão abdominal e lesão pulmonar aguda Factors associated with variation in intracranial pressure in a model of intra-abdominal hypertension with acute lung injury

    Directory of Open Access Journals (Sweden)

    Fernando Godinho Zampieri

    2011-06-01

    Full Text Available OBJETIVO: Avaliar o efeito de alterações hemodinâmicas, respiratórias e metabólicas sobre a pressão intracraniana em um modelo de lesão pulmonar aguda e síndrome compartimental abdominal. MÉTODOS: Oito porcos Agroceres foram submetidos, após a instrumentação, a cinco cenários clínicos: 1 estado basal com baixa pressão intra-abdominal e pulmão sadio; 2 pneumoperitôneo, com pressão intra-abdominal de 20 mm Hg; 3 lesão pulmonar aguda induzida por lavagem pulmonar e desativação de surfactante; 4 pneumoperitôneo com pressão intra-abdominal de 20 mm Hg na vigência de lesão pulmonar aguda e com PEEP baixo; e 5 PEEP ajustado a 27 cm H2O na vigência de pneumoperitôneo e lesão pulmonar aguda. Variáveis respiratórias e hemodinâmicas foram coletadas. Análise multivariada foi realizada buscando as variáveis associadas com elevação da pressão intracraniana nos cinco cenários estudados. RESULTADOS: Após a análise multivariada, nas situações não associadas com lesão pulmonar aguda apenas a pressão de platô das vias aéreas se correlacionou positivamente com a pressão intracraniana. Nos modelos associados com lesão pulmonar aguda, a pressão de platô de vias aéreas, a pressão arterial de CO2, o CO2 no final da expiração e a pressão venosa central se correlacionaram positivamente com incrementos da pressão intracraniana. CONCLUSÃO: Em um modelo de disfunção orgânica múltipla com situações clínicas associadas com aumento da pressão torácica e abdominal, o incremento da pressão intracraniana desencadeado pela elevação da pressão abdominal parece ser decorrente da piora da complacência do sistema respiratório e da redução do gradiente para drenagem venosa cerebral ocasionado pela elevação da pressão venosa central.OBJECTIVE: To evaluate the effects of hemodynamic, respiratory and metabolic changes on intracranial pressure in a model of acute lung injury and abdominal compartment syndrome

  14. The feasibility and effectiveness of high-intensity boxing training versus moderate-intensity brisk walking in adults with abdominal obesity: a pilot study.

    Science.gov (United States)

    Cheema, Birinder S; Davies, Timothy B; Stewart, Matthew; Papalia, Shona; Atlantis, Evan

    2015-01-01

    High-intensity interval training (HIIT) performed on exercise cycle or treadmill is considered safe and often more beneficial for fat loss and cardiometabolic health than moderate-intensity continuous training (MICT). The aim of this pilot study was to assess the feasibility and effectiveness of a 12-week boxing training (HIIT) intervention compared with an equivalent dose of brisk walking (MICT) in obese adults. Men and women with abdominal obesity and body mass index >25 kg/m(2) were randomized to either a boxing group or a brisk walking (control) group for 12 weeks. Each group engaged in 4 training sessions per week, equated for total physical activity. Feasibility outcomes included recruitment rates, assessment of training intensities, adherence and adverse events. Effectiveness was assessed pre and post intervention via pertinent obesity-, cardiovascular-, and health-related quality of life (HRQoL) outcomes. Nineteen individuals expressed an interest and 63% (n = 12) consented. Recruitment was slower than anticipated (1.3 participants/week). The boxing group trained at a significantly higher intensity each week versus the brisk walking group (p boxing group experienced an adverse event; both continued to exercise with modifications to the exercise program. No other adverse events were noted. The boxing group attended more sessions (79% vs. 55%) and had a lower attrition rate (n = 0 vs. n = 2) than the walking group. Analysis of covariance revealed that the boxing group significantly improved body fat percentage (p = 0.047), systolic blood pressure (p = 0.026), augmentation index (AIx; p Boxing training (HIIT) in adults with abdominal obesity is feasible and may elicit a better therapeutic effect on obesity, cardiovascular, and HRQoL outcomes than an equivalent dose of brisk walking (MICT). Robustly designed randomized controlled trials are required to confirm these findings and inform clinical guidelines and practice for obesity

  15. [Management of abdominal compartment syndrome after transurethral resection of the prostate].

    Science.gov (United States)

    Gaut, Megan M; Ortiz, Jaime

    2015-01-01

    Acute abdominal compartment syndrome is most commonly associated with blunt abdominal trauma, although it has been seen after ruptured abdominal aortic aneurysm, liver transplantation, pancreatitis, and massive volume resuscitation. Acute abdominal compartment syndrome develops once the intra-abdominal pressure increases to 20-25mmHg and is characterized by an increase in airway pressures, inadequate ventilation and oxygenation, altered renal function, and hemodynamic instability. This case report details the development of acute abdominal compartment syndrome during transurethral resection of the prostate with extra- and intraperitoneal bladder rupture under general anesthesia. The first signs of acute abdominal compartment syndrome in this patient were high peak airway pressures and difficulty delivering tidal volumes. Management of the compartment syndrome included re-intubation, emergent exploratory laparotomy, and drainage of irrigation fluid. Difficulty with ventilation should alert the anesthesiologist to consider abdominal compartment syndrome high in the list of differential diagnoses during any endoscopic bladder or bowel case. Copyright © 2013 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

  16. Management of abdominal compartment syndrome after transurethral resection of the prostate.

    Science.gov (United States)

    Gaut, Megan M; Ortiz, Jaime

    2015-01-01

    Acute abdominal compartment syndrome is most commonly associated with blunt abdominal trauma, although it has been seen after ruptured abdominal aortic aneurysm, liver transplantation, pancreatitis, and massive volume resuscitation. Acute abdominal compartment syndrome develops once the intra-abdominal pressure increases to 20-25 mmHg and is characterized by an increase in airway pressures, inadequate ventilation and oxygenation, altered renal function, and hemodynamic instability. This case report details the development of acute abdominal compartment syndrome during transurethral resection of the prostate with extra- and intraperitoneal bladder rupture under general anesthesia. The first signs of acute abdominal compartment syndrome in this patient were high peak airway pressures and difficulty delivering tidal volumes. Management of the compartment syndrome included re-intubation, emergent exploratory laparotomy, and drainage of irrigation fluid. Difficulty with ventilation should alert the anesthesiologist to consider abdominal compartment syndrome high in the list of differential diagnoses during any endoscopic bladder or bowel case. Copyright © 2013 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

  17. Protection against high intravascular pressure in giraffe legs

    DEFF Research Database (Denmark)

    Petersen, Karin K; Hørlyck, Arne; Østergaard, Kristine Hovkjær

    2013-01-01

    The high blood pressure in giraffe leg arteries renders giraffes vulnerable to edema. We investigated in 11 giraffes whether large and small arteries in the legs and the tight fascia protect leg capillaries. Ultrasound imaging of foreleg arteries in anesthetized giraffes and ex vivo examination....... All three findings can contribute to protection of the capillaries in giraffe legs from a high arterial pressure....... revealed abrupt thickening of the arterial wall and a reduction of its internal diameter just below the elbow. At and distal to this narrowing, the artery constricted spontaneously and in response to norepinephrine and intravascular pressure recordings revealed a dynamic, viscous pressure drop along...

  18. On some hydrogen bond correlations at high pressures

    Science.gov (United States)

    Sikka, S. K.

    2007-09-01

    In situ high pressure neutron diffraction measured lengths of O H and H O pairs in hydrogen bonds in substances are shown to follow the correlation between them established from 0.1 MPa data on different chemical compounds. In particular, the conclusion by Nelmes et al that their high pressure data on ice VIII differ from it is not supported. For compounds in which the O H stretching frequencies red shift under pressure, it is shown that wherever structural data is available, they follow the stretching frequency versus H O (or O O) distance correlation. For compounds displaying blue shifts with pressure an analogy appears to exist with improper hydrogen bonds.

  19. High-pressure applications in medicine and pharmacology

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Jerson L; Foguel, Debora; Suarez, Marisa; Gomes, Andre M O; Oliveira, Andrea C [Centro Nacional de Ressonancia Magnetica Nuclear, Departamento de Bioquimica Medica, Instituto de Ciencias Biomedicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-590 (Brazil)

    2004-04-14

    High pressure has emerged as an important tool to tackle several problems in medicine and biotechnology. Misfolded proteins, aggregates and amyloids have been studied, which point toward the understanding of the protein misfolding diseases. High hydrostatic pressure (HHP) has also been used to dissociate non-amyloid aggregates and inclusion bodies. The diverse range of diseases that result from protein misfolding has made this theme an important research focus for pharmaceutical and biotech companies. The use of high pressure promises to contribute to identifying the mechanisms behind these defects and creating therapies against these diseases. High pressure has also been used to study viruses and other infectious agents for the purpose of sterilization and in the development of vaccines. Using pressure, we have detected the presence of a ribonucleoprotein intermediate, where the coat protein is partially unfolded but bound to RNA. These intermediates are potential targets for antiviral compounds. The ability of pressure to inactivate viruses, prions and bacteria has been evaluated with a view toward the applications of vaccine development and virus sterilization. Recent studies demonstrate that pressure causes virus inactivation while preserving the immunogenic properties. There is increasing evidence that a high-pressure cycle traps a virus in the 'fusion intermediate state', not infectious but highly immunogenic.

  20. High-pressure applications in medicine and pharmacology

    Science.gov (United States)

    Silva, Jerson L.; Foguel, Debora; Suarez, Marisa; Gomes, Andre M. O.; Oliveira, Andréa C.

    2004-04-01

    High pressure has emerged as an important tool to tackle several problems in medicine and biotechnology. Misfolded proteins, aggregates and amyloids have been studied, which point toward the understanding of the protein misfolding diseases. High hydrostatic pressure (HHP) has also been used to dissociate non-amyloid aggregates and inclusion bodies. The diverse range of diseases that result from protein misfolding has made this theme an important research focus for pharmaceutical and biotech companies. The use of high pressure promises to contribute to identifying the mechanisms behind these defects and creating therapies against these diseases. High pressure has also been used to study viruses and other infectious agents for the purpose of sterilization and in the development of vaccines. Using pressure, we have detected the presence of a ribonucleoprotein intermediate, where the coat protein is partially unfolded but bound to RNA. These intermediates are potential targets for antiviral compounds. The ability of pressure to inactivate viruses, prions and bacteria has been evaluated with a view toward the applications of vaccine development and virus sterilization. Recent studies demonstrate that pressure causes virus inactivation while preserving the immunogenic properties. There is increasing evidence that a high-pressure cycle traps a virus in the 'fusion intermediate state', not infectious but highly immunogenic.

  1. Temperature control for high pressure processes up to 1400 MPa

    Science.gov (United States)

    Reineke, K.; Mathys, A.; Heinz, V.; Knorr, D.

    2008-07-01

    Pressure- assisted sterilisation is an emerging technology. Hydrostatic high pressure can reduce the thermal load of the product and this allows quality retention in food products. To guarantee the safety of the sterilisation process it is necessary to investigate inactivation kinetics especially of bacterial spores. A significant roll during the inactivation of microorganisms under high pressure has the thermodynamic effect of the adiabatic heating. To analyse the individual effect of pressure and temperature on microorganism inactivation an exact temperature control of the sample to reach ideal adiabatic conditions and isothermal dwell times is necessary. Hence a heating/cooling block for a high pressure unit (Stansted Mini-Food-lab; high pressure capillary with 300 μL sample volume) was constructed. Without temperature control the sample would be cooled down during pressure built up, because of the non-adiabatic heating of the steel made vessel. The heating/cooling block allows an ideal adiabatic heat up and cooling of the pressure vessel during compression and decompression. The high pressure unit has a pressure build-up rate up to 250 MPa s-1 and a maximum pressure of 1400 MPa. Sebacate acid was chosen as pressure transmitting medium because it had no phase shift over the investigate pressure and temperature range. To eliminate the temperature difference between sample and vessel during compression and decompression phase, the mathematical model of the adiabatic heating/cooling of water and sebacate acid was implemented into a computational routine, written in Test Point. The calculated temperature is the setpoint of the PID controller for the heating/cooling block. This software allows an online measurement of the pressure and temperature in the vessel and the temperature at the outer wall of the vessel. The accurate temperature control, including the model of the adiabatic heating opens up the possibility to realise an ideal adiabatic heating and cooling as

  2. Temperature control for high pressure processes up to 1400 MPa

    Energy Technology Data Exchange (ETDEWEB)

    Reineke, K; Mathys, A; Knorr, D [Berlin University of Technology, Department of Food Biotechnology and Food Process Engineering, Koenigin-Luise-Str. 22, D-14195 Berlin (Germany); Heinz, V [German Institute of Food Technology, p. o. box: 1165, D-49601, Quackenbrueck (Germany)], E-mail: alexander.mathys@tu-berlin.de

    2008-07-15

    Pressure- assisted sterilisation is an emerging technology. Hydrostatic high pressure can reduce the thermal load of the product and this allows quality retention in food products. To guarantee the safety of the sterilisation process it is necessary to investigate inactivation kinetics especially of bacterial spores. A significant roll during the inactivation of microorganisms under high pressure has the thermodynamic effect of the adiabatic heating. To analyse the individual effect of pressure and temperature on microorganism inactivation an exact temperature control of the sample to reach ideal adiabatic conditions and isothermal dwell times is necessary. Hence a heating/cooling block for a high pressure unit (Stansted Mini-Food-lab; high pressure capillary with 300 {mu}L sample volume) was constructed. Without temperature control the sample would be cooled down during pressure built up, because of the non-adiabatic heating of the steel made vessel. The heating/cooling block allows an ideal adiabatic heat up and cooling of the pressure vessel during compression and decompression. The high pressure unit has a pressure build-up rate up to 250 MPa s{sup -1} and a maximum pressure of 1400 MPa. Sebacate acid was chosen as pressure transmitting medium because it had no phase shift over the investigate pressure and temperature range. To eliminate the temperature difference between sample and vessel during compression and decompression phase, the mathematical model of the adiabatic heating/cooling of water and sebacate acid was implemented into a computational routine, written in Test Point. The calculated temperature is the setpoint of the PID controller for the heating/cooling block. This software allows an online measurement of the pressure and temperature in the vessel and the temperature at the outer wall of the vessel. The accurate temperature control, including the model of the adiabatic heating opens up the possibility to realise an ideal adiabatic heating and

  3. High pressure Moessbauer spectroscopy of perovskite iron oxide

    CERN Document Server

    Nasu, S; Morimoto, S; Kawakami, T; Kuzushita, K; Takano, M

    2003-01-01

    High-pressure sup 5 sup 7 Fe Moessbauer spectroscopy using a diamond anvil cell has been performed for perovskite iron oxides SrFeO sub 3 , CaFeO sub 3 and La sub 1 sub / sub 3 Sr sub 2 sub / sub 3 O sub 3. The charge states and the magnetic dependency to pressure were determined. Pressure magnetic phase diagrams of these perovskite iron oxides are determined up to about 70 GPa. To be clear the magnetic ordered state, they are measured up to 7.8 T external magnetic fields at 4.5K. The phase transition of these perovskite oxides to ferromagnetisms with high magnetic ordered temperature is observed. In higher pressure, high spin-low spin transition of oxides besides CaFeO sub 3 is generated. The feature of Moessbauer spectroscopy, perovskite iron oxide and Moessbauer spectroscopy under high pressure are explained. (S.Y.)

  4. Abdominal Sepsis.

    Science.gov (United States)

    De Waele, Jan J

    2016-08-01

    Abdominal infections are an important challenge for the intensive care physician. In an era of increasing antimicrobial resistance, selecting the appropriate regimen is important and, with new drugs coming to the market, correct use is important more than ever before and abdominal infections are an excellent target for antimicrobial stewardship programs. Biomarkers may be helpful, but their exact role in managing abdominal infections remains incompletely understood. Source control also remains an ongoing conundrum, and evidence is increasing that its importance supersedes the impact of antibiotic therapy. New strategies such as open abdomen management may offer added benefit in severely ill patients, but more data are needed to identify its exact role. The role of fungi and the need for antifungal coverage, on the other hand, have been investigated extensively in recent years, but at this point, it remains unclear who requires empirical as well as directed therapy.

  5. HIGH TEMPERATURE HIGH PRESSURE THERMODYNAMIC MEASUREMENTS FOR COAL MODEL COMPOUNDS

    Energy Technology Data Exchange (ETDEWEB)

    Vinayak N. Kabadi

    2000-05-01

    The flow VLE apparatus designed and built for a previous project was upgraded and recalibrated for data measurements for this project. The modifications include better and more accurate sampling technique, addition of a digital recorder to monitor temperature and pressure inside the VLE cell, and a new technique for remote sensing of the liquid level in the cell. VLE data measurements for three binary systems, tetralin-quinoline, benzene--ethylbenzene and ethylbenzene--quinoline, have been completed. The temperature ranges of data measurements were 325 C to 370 C for the first system, 180 C to 300 C for the second system, and 225 C to 380 C for the third system. The smoothed data were found to be fairly well behaved when subjected to thermodynamic consistency tests. SETARAM C-80 calorimeter was used for incremental enthalpy and heat capacity measurements for benzene--ethylbenzene binary liquid mixtures. Data were measured from 30 C to 285 C for liquid mixtures covering the entire composition range. An apparatus has been designed for simultaneous measurement of excess volume and incremental enthalpy of liquid mixtures at temperatures from 30 C to 300 C. The apparatus has been tested and is ready for data measurements. A flow apparatus for measurement of heat of mixing of liquid mixtures at high temperatures has also been designed, and is currently being tested and calibrated.

  6. High pressure, high strain rate material strength studies

    Science.gov (United States)

    Remington, B. A.; Arsenlis, A.; Barton, N.; Belof, J.; Cavallo, R.; Maddox, B.; Park, H.-S.; Prisbrey, S.; Rudd, R.; Comley, A.; Meyers, M.; Wark, J.

    2011-10-01

    Constitutive models for material strength are currently being tested at high pressures by comparing 2D simulations with experiments measuring the Rayleigh-Taylor (RT) instability evolution in solid-state samples of vanadium (V), tantalum (Ta), and iron (Fe). The multiscale strength models being tested combine molecular dynamics, dislocation dynamics, and continuum simulations. Our analysis for the V experiments suggests that the material deformation at these conditions falls into the phonon drag regime, whereas for Ta, the deformation resides mainly in the thermal activation regime. Recent Fe-RT experiments suggest perturbation growth about the alpha-epsilon (bcc-hcp) phase transition threshold has been observed. Using the LLNL multiscale models, we decompose the strength as a function of strain rate into its dominant components of thermal activation, phonon drag, and work hardening. We have also developed a dynamic diffraction diagnostic technique to measure strength directly from shock compressed single crystal samples. Finally, recovery experiments allow a comparison of residual dislocation density with predictions from the multiscale model. This work performed under the auspices of the U.S. DoE by LLNL Security, LLC under Contract DE-AC52-07NA27344.

  7. Synthetic chemistry with periodic mesostructures at high pressure.

    Science.gov (United States)

    Mandal, Manik; Landskron, Kai

    2013-11-19

    Over the last two decades, researchers have studied extensively the synthesis of mesostructured materials, which could be useful for drug delivery, catalytic cracking of petroleum, or reinforced plastics, among other applications. However, until very recently researchers used only temperature as a thermodynamic variable for synthesis, completely neglecting pressure. In this Account, we show how pressure can affect the synthetic chemistry of periodic mesoporous structures with desirable effects. In its simplest application, pressure can crystallize the pore walls of periodic mesoporous silicas, which are difficult to crystallize otherwise. The motivation for the synthesis of periodic mesoporous silica materials (with pore sizes from 2 to 50 nm) 20 years ago was to replace the microporous zeolites (which have pore sizes of machining, drilling, and polishing. Overall, the results show that periodic mesoporous materials are suitable starting materials for the synthesis of nanoporous high-pressure phases and nanocrystals of high pressure phases. The substantially enhanced hydrothermal stability seen in periodic mesoporous silicas synthesized at high pressure demonstrates that high pressure can be a useful tool to produce porous materials with improved properties. We expect that synthesis using mesostructures at high pressure can be extended to many other materials beyond silicas and carbons. Presumably, this chemistry can also be extended from mesoporous to microporous and macroporous materials.

  8. Design principles for high-pressure force fields: Aqueous TMAO solutions from ambient to kilobar pressures

    Science.gov (United States)

    Hölzl, Christoph; Kibies, Patrick; Imoto, Sho; Frach, Roland; Suladze, Saba; Winter, Roland; Marx, Dominik; Horinek, Dominik; Kast, Stefan M.

    2016-04-01

    Accurate force fields are one of the major pillars on which successful molecular dynamics simulations of complex biomolecular processes rest. They have been optimized for ambient conditions, whereas high-pressure simulations become increasingly important in pressure perturbation studies, using pressure as an independent thermodynamic variable. Here, we explore the design of non-polarizable force fields tailored to work well in the realm of kilobar pressures - while avoiding complete reparameterization. Our key is to first compute the pressure-induced electronic and structural response of a solute by combining an integral equation approach to include pressure effects on solvent structure with a quantum-chemical treatment of the solute within the embedded cluster reference interaction site model (EC-RISM) framework. Next, the solute's response to compression is taken into account by introducing pressure-dependence into selected parameters of a well-established force field. In our proof-of-principle study, the full machinery is applied to N,N,N-trimethylamine-N-oxide (TMAO) in water being a potent osmolyte that counteracts pressure denaturation. EC-RISM theory is shown to describe well the charge redistribution upon compression of TMAO(aq) to 10 kbar, which is then embodied in force field molecular dynamics by pressure-dependent partial charges. The performance of the high pressure force field is assessed by comparing to experimental and ab initio molecular dynamics data. Beyond its broad usefulness for designing non-polarizable force fields for extreme thermodynamic conditions, a good description of the pressure-response of solutions is highly recommended when constructing and validating polarizable force fields.

  9. High pressure optical studies of crystalline anils and related compounds

    Energy Technology Data Exchange (ETDEWEB)

    Hockert, E.N.; Drickamer, H.G.

    1977-12-01

    High pressure optical studies have been made on a series of crystalline therochromic and photochromic anils and model compounds. Measurements include absorption and emission peak locations and the integrated intensities of various absorption peaks including the uv peak and visible peaks introduced thermally or by irradiation at various temperatures and pressures. Emission yields were also obtained. For the thermochromic compounds there was a large increase in the equilibrium yield of the thermally induced peak with pressure (piezochromism), corresponding to a volume decrease of approx.1.2 cc/mole for 5-bromosalicylidene aniline (5BrSA). The emission peak shifts to lower energy and decreases in intensity primarily because of increased rate of the radiationless conversion. For salicylidene aniline and related photochromic crystals the rate of photochromic conversion varied with both pressure and temperature in a manner which depends on the size of the energy barriers to the forward and reverse processes. The emission yield increases with pressure at low pressure, goes through a maximum, and decreases at high pressure. At low pressure the dominant feature is increase in occupation of the emitting state while at high pressure the increased rate of the radiationless process governs. For 2- (O-hydroxyphenyl) benzoxazole (OHBO) (see Fig. 1), where a keto--enol rearrangement is most probable, the changes in absorption and emission intensity can be related to the same diagram used for the anils. This diagram also describes the behavior of benzilidene aniline (BA), where only a cis--trans isomerization is possible.

  10. La medición de la presión intrabdominal, una herramienta diagnóstica para el médico de familia Intra-abdominal pressure measurement, a diagnostic tool for family physician

    Directory of Open Access Journals (Sweden)

    Nizahel Estévez Álvarez

    2010-09-01

    Full Text Available Resulta muy oportuno establecer un diagnóstico precoz de las afecciones intrabdominales agudas, por eso consideramos prudente poner en manos de nuestro personal de salud que labora en el sistema de urgencia del nivel primario, una herramienta diagnóstica más para el Médico de Familia, como es la medición de la presión intrabdominal, por no existir prácticamente experiencias de su empleo fuera de las unidades de atención al paciente grave. Es este un método perfectamente implementable en nuestro medio por su fácil aplicabilidad técnica y su alta especificidad diagnóstica, que permite inferir, en las primeras horas de evolución de los pacientes con cuadros dolorosos abdominales, cuáles resultarían potencialmente necesitados de tratamiento quirúrgico, y de esta manera, ganar en resolutividad. La imposibilidad de realizar esta técnica nunca debería de retrasar la remisión del paciente para su valoración por un especialista en cirugía general, por tanto, esta solo pudiera ser considerada como un complemento más del arsenal diagnóstico al alcance del Médico de Familia, en centros acondicionados para su implementación y con el entrenamiento previo adecuado.It is very appropriate to establish an early diagnosis of acute intra-abdominal infections, thus, authors believe cautious that our health staff working in the primary level of emergence system to count on another diagnostic tool for Family Physician, the intra-abdominal pressure measurement, due to practically the lack of experience of its job out of the care units for the severe patient. This is a method perfectly applicable in our environment by its easy technical application and its high diagnostic specificity allowing inferring during the first hours of evolution of patients presenting with abdominal painful symptoms, who will be potentially needed of surgical treatment and so to achieve a solution. The impossibility to perform this technique never must to retard the

  11. The OPERA trial - comparison of early nasal high flow oxygen therapy with standard care for prevention of postoperative hypoxemia after abdominal surgery: study protocol for a multicenter randomized controlled trial.

    Science.gov (United States)

    Futier, Emmanuel; Paugam-Burtz, Catherine; Constantin, Jean-Michel; Pereira, Bruno; Jaber, Samir

    2013-10-18

    Respiratory support following postoperative extubation is of major importance to prevent hypoxemia and subsequent respiratory failure and reintubation. High-flow nasal cannula oxygen (HFNC) delivers a flow-dependent positive airway pressure and improves oxygenation by increasing end-expiratory lung volume. Whether application of HFNC may have therapeutic advantages over conventional oxygen therapy for respiratory support in the early postextubation surgical period remains to be established. The Optiflow for prevention of post-extubation hypoxemia after abdominal surgery (OPERA) trial is an investigator-initiated multicenter randomized controlled two-arm trial with assessor-blinded outcome assessment, randomizing 220 patients with intermediate to high risk of pulmonary complications after abdominal surgery to receive HFNC or conventional oxygen therapy following extubation, stratified by the presence of epidural analgesia and center. The primary outcome measure is the percentage of patients with postoperative hypoxemia one hour after tracheal extubation. Secondary outcome measures are postoperative pulmonary complications, need for noninvasive ventilation and intubation for respiratory failure. The OPERA trial is the first randomized controlled study powered to investigate whether early application of HFNC following extubation after abdominal surgery prevents against postoperative hypoxemia and pulmonary complications. ClinicalTrials.gov Identifier: NCT01887015.

  12. Viscosity of mafic magmas at high pressures

    Science.gov (United States)

    Cochain, B.; Sanloup, C.; Leroy, C.; Kono, Y.

    2017-01-01

    While it is accepted that silica-rich melts behave anomalously with a decrease of their viscosity at increased pressures (P), the viscosity of silica-poor melts is much less constrained. However, modeling of mantle melts dynamics throughout Earth's history, including the magma ocean era, requires precise knowledge of the viscous properties of silica-poor magmas. We extend here our previous measurements on fayalite melt to natural end-members pyroxenite melts (MgSiO3 and CaSiO3) using in situ X-ray radiography up to 8 GPa. For all compositions, viscosity decreases with P, rapidly below 5 GPa and slowly above. The magnitude of the viscosity decrease is larger for pyroxene melts than for fayalite melt and larger for the Ca end-member within pyroxene melts. The anomalous viscosity decrease appears to be a universal behavior for magmas up to 13 GPa, while the P dependence of viscosity beyond this remains to be measured. These results imply that mantle melts are very pervasive at depth.

  13. Studies of Alkali Sorption Kinetics for Pressurized Fluidized Bed Combustion by High Pressure Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, K.J.; Willenborg, W.; Fricke, C.; Prikhodovsky, A.; Hilpert, K.; Singheiser, L.

    2002-09-20

    This work describes the first approach to use High Pressure Mass Spectrometry (HPMS) for the quantification and analysis of alkali species in a gas stream downstream a sorbent bed of different tested alumosilicates.

  14. Underground storage systems for high-pressure air and gases

    Science.gov (United States)

    Beam, B. H.; Giovannetti, A.

    1975-01-01

    This paper is a discussion of the safety and cost of underground high-pressure air and gas storage systems based on recent experience with a high-pressure air system installed at Moffett Field, California. The system described used threaded and coupled oil well casings installed vertically to a depth of 1200 ft. Maximum pressure was 3000 psi and capacity was 500,000 lb of air. A failure mode analysis is presented, and it is shown that underground storage offers advantages in avoiding catastrophic consequences from pressure vessel failure. Certain problems such as corrosion, fatigue, and electrolysis are discussed in terms of the economic life of such vessels. A cost analysis shows that where favorable drilling conditions exist, the cost of underground high-pressure storage is approximately one-quarter that of equivalent aboveground storage.

  15. Pressure ratio effects on self-similar scalar mixing of high-pressure turbulent jets in a pressurized volume

    Science.gov (United States)

    Ruggles, Adam; Pickett, Lyle; Frank, Jonathan

    2014-11-01

    Many real world combustion devices model fuel scalar mixing by assuming the self-similar argument established in atmospheric free jets. This allows simple prediction of the mean and rms fuel scalar fields to describe the mixing. This approach has been adopted in super critical liquid injections found in diesel engines where the liquid behaves as a dense fluid. The effect of pressure ratio (injection to ambient) when the ambient is greater than atmospheric pressure, upon the self-similar collapse has not been well characterized, particularly the effect upon mixing constants, jet spreading rates, and virtual origins. Changes in these self-similar parameters control the reproduction of the scalar mixing statistics. This experiment investigates the steady state mixing of high pressure ethylene jets in a pressurized pure nitrogen environment for various pressure ratios and jet orifice diameters. Quantitative laser Rayleigh scattering imaging was performed utilizing a calibration procedure to account for the pressure effects upon scattering interference within the high-pressure vessel.

  16. DASH diet to lower high blood pressure

    Science.gov (United States)

    ... that are naturally low in salt, cholesterol, and saturated fats. You will also include foods that are high ... AHA/ACC guideline on lifestyle management to reduce cardiovascular risk: a report of the American College of ...

  17. A Study on Development of Variable High Pressurizer Pressure Trip Function to Mitigate System Peak Pressure during Transients for Pressurized Water Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ung Soo; Park, Min Soo; Huh, Jae Young; Lee, Gyu Cheon [KEPCO Engineering and Construction, Daejeon (Korea, Republic of)

    2016-10-15

    According to intensified regulation environment such as separate safety analysis for the reactor coolant system (RCS) and the main steam system peak pressure, strict consideration of a control system malfunction as a single failure for the safety analysis and so on, the safety margin with respect to system pressure of pressurized water reactors (PWRs) has been decreased. Also, the possibility for that the main steam system pressure may violate the acceptance criteria during the LOCV event has been raised and relevant design modifications for the main steam safety valve (MSSV) have ever been performed as a solution. In order to overcome this problem, in this work, the variable high pressurizer pressure trip (VHPPT) function has been developed and a feasibility study on the application of this trip function has been performed. The VHPPT function has been devised to trip the reactor beforehand when a sharply pressurizing transient such as the LOCV occurs and to cutoff system pressure increase, resulting in reducing the system peak pressure. In this work, the VHPPT function has been suggested and developed to trip the reactor beforehand and to cutoff system pressure increase mitigating the system peak pressure of PWRs when a sharply pressurizing transient like the LOCV occurs. The VHPPT function uses the rate-limited variable setpoint and includes the existing HPPT function.

  18. High-pressure ignition plasma torch for aerospace testing facilities

    Science.gov (United States)

    Yusupov, D. I.; Kulikov, Yu M.; Gadzhiev, M. Kh; Tyuftyaev, A. S.; Son, E. E.

    2016-11-01

    The present paper discusses the issues of implementation of high-pressure ignition plasma torch in terms of discharge phenomena in compressed gases, dense nitrogen plasma properties and stable arcing power requirements. Contact ignition has been tested in a pressure range p = 1-25 bar and has proved to be a reliable solution for pilot arc burning.

  19. Investigation of Methacrylic Acid at High Pressure Using Neutron Diffraction

    DEFF Research Database (Denmark)

    Marshall, William G.; Urquhart, Andrew; Oswald, Iain D. H.

    2015-01-01

    This article shows that pressure can be a low-intensity route to the synthesis of polymethacrylic acid. The exploration of perdeuterated methacrylic acid at high pressure using neutron diffraction reveals that methacrylic acid exhibits two polymorphic phase transformations at relatively low press...

  20. High-pressure saline washing of allografts reduces bacterial contamination.

    Science.gov (United States)

    Hirn, M Y; Salmela, P M; Vuento, R E

    2001-02-01

    60 fresh-frozen bone allografts were contaminated on the operating room floor. No bacterial growth was detected in 5 of them after contamination. The remaining 55 grafts had positive bacterial cultures and were processed with three methods: soaking in saline, soaking in antibiotic solution or washing by high-pressure saline. After high-pressure lavage, the cultures were negative in three fourths of the contaminated allografts. The corresponding figures after soaking grafts in saline and antibiotic solution were one tenth and two tenths, respectively. High-pressure saline cleansing of allografts can be recommended because it improves safety by reducing the superficial bacterial bioburden.

  1. Teaming Up Against High Blood Pressure PSA (:60)

    Centers for Disease Control (CDC) Podcasts

    2012-09-04

    Nearly one-third of American adults have high blood pressure, and more than half of them don’t have it under control. Simply seeing a doctor and taking medications isn’t enough for many people who have high blood pressure. A team-based approach by patients, health care systems, and health care providers is one of the best ways to treat uncontrolled high blood pressure.  Created: 9/4/2012 by Centers for Disease Control and Prevention (CDC).   Date Released: 9/4/2012.

  2. Recent Results on High-Pressure Axial Blowers

    Science.gov (United States)

    Eckert, B.

    1947-01-01

    Considerable progress has, in recent times, been attained in the development of the high-pressure axial blower by well-planned research. The efforts are directed toward improving the efficiencies, which are already high for the axial blower, and in particular the delivery pressure heads. For high pressures multistage arrangements are used. Of fundamental importance is the careful design of all structural parts of the blower that are subject to the effects of the flow. In the present report, several recent results and experiences are reported, which are based on results of German engine research.

  3. Safety analysis of high pressure gasous fuel container punctures

    Energy Technology Data Exchange (ETDEWEB)

    Swain, M.R. [Univ. of Miami, Coral Gables, FL (United States)

    1995-09-01

    The following report is divided into two sections. The first section describes the results of ignitability tests of high pressure hydrogen and natural gas leaks. The volume of ignitable gases formed by leaking hydrogen or natural gas were measured. Leaking high pressure hydrogen produced a cone of ignitable gases with 28{degrees} included angle. Leaking high pressure methane produced a cone of ignitable gases with 20{degrees} included angle. Ignition of hydrogen produced larger overpressures than did natural gas. The largest overpressures produced by hydrogen were the same as overpressures produced by inflating a 11 inch child`s balloon until it burst.

  4. Excessively High Vapor Pressure of Al-based Amorphous Alloys

    Directory of Open Access Journals (Sweden)

    Jae Im Jeong

    2015-10-01

    Full Text Available Aluminum-based amorphous alloys exhibited an abnormally high vapor pressure at their approximate glass transition temperatures. The vapor pressure was confirmed by the formation of Al nanocrystallites from condensation, which was attributed to weight loss of the amorphous alloys. The amount of weight loss varied with the amorphous alloy compositions and was inversely proportional to their glass-forming ability. The vapor pressure of the amorphous alloys around 573 K was close to the vapor pressure of crystalline Al near its melting temperature, 873 K. Our results strongly suggest the possibility of fabricating nanocrystallites or thin films by evaporation at low temperatures.

  5. Pasteurization of food by hydrostatic high pressure: chemical aspects.

    Science.gov (United States)

    Tauscher, B

    1995-01-01

    Food pasteurized by hydrostatic high pressure have already been marketed in Japan. There is great interest in this method also in Europe and USA. Temperature and pressure are the essential parameters influencing the state of substances including foods. While the influence of temperature on food has been extensively investigated, effects of pressure, also in combination with temperature, are attracting increasing scientific attention now. Processes and reactions in food governed by Le Chatelier's principle are of special interest; they include chemical reactions of both low- and macromolecular compounds. Theoretical fundamentals and examples of pressure affected reactions are presented.

  6. Isostructural Transition of MgB2 Under High Pressure

    Institute of Scientific and Technical Information of China (English)

    SUN Li-Ling; WU Qi; ZHAN Zai-Ji; WANG Wen-Kui; WANG Wen-Kui; T.Kikegawa

    2001-01-01

    The high-pressure behaviour of the superconductor MgB2 with a hexagonal structure has been investigated by the in situ synchrotron radiation x-ray diffraction method under pressures up to 42.2 GPa in a diamond anvil cell. An abrupt decrease of about 7% in the unit cell volume of this material occurs in the pressure range of 26.3-30.2 GPa. A split of the Raman spectrum was also observed. The jump of the compression curve and Raman spectrum are ascribed to an isostructural transition in MgB2 at a pressure of 30.2 GPa.

  7. Highly compressible fluorescent particles for pressure sensing in liquids

    Science.gov (United States)

    Cellini, F.; Peterson, S. D.; Porfiri, M.

    2017-05-01

    Pressure sensing in liquids is important for engineering applications ranging from industrial processing to naval architecture. Here, we propose a pressure sensor based on highly compressible polydimethylsiloxane foam particles embedding fluorescent Nile Red molecules. The particles display pressure sensitivities as low as 0.0018 kPa-1, which are on the same order of magnitude of sensitivities reported in commercial pressure-sensitive paints for air flows. We envision the application of the proposed sensor in particle image velocimetry toward an improved understanding of flow kinetics in liquids.

  8. Effect of High Pressure and Heat on Bacterial Toxins

    Directory of Open Access Journals (Sweden)

    Dirk Margosch

    2005-01-01

    Full Text Available Even though the inactivation of microorganisms by high pressure treatment is a subject of intense investigations, the effect of high pressure on bacterial toxins has not been studied so far. In this study, the influence of combined pressure/temperature treatment (0.1 to 800 MPa and 5 to 121 °C on bacterial enterotoxins was determined. Therefore, heat-stable enterotoxin (STa of cholera toxin (CT from Vibrio cholerae, staphylococcal enterotoxins A-E, haemolysin BL (HBL from Bacillus cereus, and Escherichia coli (STa were subjected to different treatment schemes. Structural alterations were monitored in enzyme immunoassays (EIAs. Cytotoxicity of the pressure treated supernatant of toxigenic B. cereus DSM 4384 was investigated with Vero cells. High pressure of 200 to 800 MPa at 5 °C leads to a slight increase of the reactivity of the STa of E. coli. However, reactivity decreased at 800 MPa and 80 °C to (66±21 % after 30 min and to (44±0.3 % after 128 min. At ambient pressure no decrease in EIA reactivity could be observed after 128 min. Pressurization (0.1 to 800 MPa of heat stable monomeric staphylococcal toxins at 5 and 20 °C showed no effect. A combined heat (80 °C and pressure (0.1 to 800 MPa treatment lead to a decrease in the immuno-reactivity to 20 % of its maximum. For cholera toxin a significant loss in latex agglutination was observable only at 80 °C and 800 MPa for holding times higher than 20 min. Interestingly, the immuno-reactivity of B. cereus HBL toxin increased with the increase of pressure (182 % at 800 MPa, 30 °C, and high pressure showed only minor effects on cytotoxicity to Vero cells. Our results indicate that pressurization can increase inactivation observed by heat treatment, and combined treatments may be effective at lower temperatures and/or shorter incubation time.

  9. Acoustic wave propagation in high-pressure system.

    Science.gov (United States)

    Foldyna, Josef; Sitek, Libor; Habán, Vladimír

    2006-12-22

    Recently, substantial attention is paid to the development of methods of generation of pulsations in high-pressure systems to produce pulsating high-speed water jets. The reason is that the introduction of pulsations into the water jets enables to increase their cutting efficiency due to the fact that the impact pressure (so-called water-hammer pressure) generated by an impact of slug of water on the target material is considerably higher than the stagnation pressure generated by corresponding continuous jet. Special method of pulsating jet generation was developed and tested extensively under the laboratory conditions at the Institute of Geonics in Ostrava. The method is based on the action of acoustic transducer on the pressure liquid and transmission of generated acoustic waves via pressure system to the nozzle. The purpose of the paper is to present results obtained during the research oriented at the determination of acoustic wave propagation in high-pressure system. The final objective of the research is to solve the problem of transmission of acoustic waves through high-pressure water to generate pulsating jet effectively even at larger distances from the acoustic source. In order to be able to simulate numerically acoustic wave propagation in the system, it is necessary among others to determine dependence of the sound speed and second kinematical viscosity on operating pressure. Method of determination of the second kinematical viscosity and speed of sound in liquid using modal analysis of response of the tube filled with liquid to the impact was developed. The response was measured by pressure sensors placed at both ends of the tube. Results obtained and presented in the paper indicate good agreement between experimental data and values of speed of sound calculated from so-called "UNESCO equation". They also show that the value of the second kinematical viscosity of water depends on the pressure.

  10. Low Cost, High Efficiency, High Pressure Hydrogen Storage

    Energy Technology Data Exchange (ETDEWEB)

    Mark Leavitt

    2010-03-31

    A technical and design evaluation was carried out to meet DOE hydrogen fuel targets for 2010. These targets consisted of a system gravimetric capacity of 2.0 kWh/kg, a system volumetric capacity of 1.5 kWh/L and a system cost of $4/kWh. In compressed hydrogen storage systems, the vast majority of the weight and volume is associated with the hydrogen storage tank. In order to meet gravimetric targets for compressed hydrogen tanks, 10,000 psi carbon resin composites were used to provide the high strength required as well as low weight. For the 10,000 psi tanks, carbon fiber is the largest portion of their cost. Quantum Technologies is a tier one hydrogen system supplier for automotive companies around the world. Over the course of the program Quantum focused on development of technology to allow the compressed hydrogen storage tank to meet DOE goals. At the start of the program in 2004 Quantum was supplying systems with a specific energy of 1.1-1.6 kWh/kg, a volumetric capacity of 1.3 kWh/L and a cost of $73/kWh. Based on the inequities between DOE targets and Quantum’s then current capabilities, focus was placed first on cost reduction and second on weight reduction. Both of these were to be accomplished without reduction of the fuel system’s performance or reliability. Three distinct areas were investigated; optimization of composite structures, development of “smart tanks” that could monitor health of tank thus allowing for lower design safety factor, and the development of “Cool Fuel” technology to allow higher density gas to be stored, thus allowing smaller/lower pressure tanks that would hold the required fuel supply. The second phase of the project deals with three additional distinct tasks focusing on composite structure optimization, liner optimization, and metal.

  11. In situ studies of microbial inactivation during high pressure processing

    Science.gov (United States)

    Maldonado, Jose Antonio; Schaffner, Donald W.; Cuitiño, Alberto M.; Karwe, Mukund V.

    2016-01-01

    High pressure processing (HPP) has been shown to reduce microbial concentration in foods. The mechanisms of microbial inactivation by HPP have been associated with damage to cell membranes. The real-time response of bacteria to HPP was measured to elucidate the mechanisms of inactivation, which can aid in designing more effective processes. Different pressure cycling conditions were used to expose Enterobacter aerogenes cells to HPP. Propidium iodide (PI) was used as a probe, which fluoresces after penetrating cells with damaged membranes and binding with nucleic acids. A HPP vessel with sapphire windows was used for measuring fluorescence in situ. Membrane damage was detected during pressurization and hold time, but not during depressurization. The drop in fluorescence was larger than expected after pressure cycles at higher pressure and longer times. This indicated possible reversible disassociation of ribosomes resulting in additional binding of PI to exposed RNA under pressure and its release after depressurization.

  12. Characterization of coaxial rocket injector sprays under high pressure environments

    Science.gov (United States)

    Sankar, S. V.; Wang, G.; Brena De La Rosa, A.; Rudoff, R. C.; Isakovic, A.; Bachalo, W. D.

    1992-01-01

    The effect of elevated environment pressures on the atomization characteristics of a single element, scaled-down, shear-coaxial rocket injector has been investigated. In this study, the shear coaxial injector was operated with water and air as simulants for conventionally used liquid oxygen and hydrogen gas, respectively. The experiments were conducted in a specially designed high pressure rig. A two-component PDPA/DSA system was used to study the spray characteristics at different chamber pressures ranging from atmospheric to 100 psig. The study showed an overall increase in the droplet sizes at higher chamber pressures. This phenomenon is attributed to a decrease in the secondary atomization effects at higher chamber pressures which, in turn, is directly related to a decrease in the shear experienced by the droplets as they move axially through the pressure chamber.

  13. Strong environmental tolerance of moss Venturiella under very high pressure

    Science.gov (United States)

    Ono, F.; Mori, Y.; Takarabe, K.; Nishihira, N.; Shindo, A.; Saigusa, M.; Matsushima, Y.; Saini, N. L.; Yamashita, M.

    2010-03-01

    It was shown by the present authors group that tardigrade can survive under high pressure of 7.5 GPa. In the case of land plants, however, no result of such experiment has been reported. We have extended our experiments to moss searching for lives under very high pressure. Spore placentas of moss Venturiella were sealed in a small Teflon capsule together with a liquid pressure medium. The capsule was put in the center of a pyrophillite cube, and the maximum pressure of 7.5 GPa was applied using a two-stage cubic anvil press. The pressure was kept constant at the maximum pressure for12, 24, 72 and 144 hours. After the pressure was released, the spores were seeded on a ager medium, and incubated for one week and more longer at 25°C with white light of 2000 lux. It was proved that 70-90% of the spores were alive and germinated after exposed to the maximum pressure of 7.5 GPa for up to 72 hours. However, after exposed to 7.5 GPa for 6 days, only 4 individuals in a hundred were germinated. The pressure tolerance of moss Venturiella is found to be stronger than a small animal, tardigrade.

  14. Strong environmental tolerance of moss Venturiella under very high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Ono, F; Mori, Y; Takarabe, K [Department of Applied Science, Okayama University of Science, 1-1 Ridaicho, Okayama 700-0005 (Japan); Nishihira, N; Shindo, A [Okayama Ichinomiya High School, Okayama 700-0005 (Japan); Saigusa, M [Department of Biology, Okayama University, 3-1-1 Tsushima-Naka, Okayama 700-8530 (Japan); Matsushima, Y [Department of Physics, Okayama University, 3-1-1 Tsushima-Naka, Okayama 700-8530 (Japan); Saini, N L [Dipartimento di Fisica, Universita di Roma ' La Sapienza' , Piazzale Aldo Moro 2, 00185 Rome (Italy); Yamashita, M, E-mail: fumihisa@das.ous.ac.j [Aerospace Exploration Agency, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510 (Japan)

    2010-03-01

    It was shown by the present authors group that tardigrade can survive under high pressure of 7.5 GPa. In the case of land plants, however, no result of such experiment has been reported. We have extended our experiments to moss searching for lives under very high pressure. Spore placentas of moss Venturiella were sealed in a small Teflon capsule together with a liquid pressure medium. The capsule was put in the center of a pyrophillite cube, and the maximum pressure of 7.5 GPa was applied using a two-stage cubic anvil press. The pressure was kept constant at the maximum pressure for12, 24, 72 and 144 hours. After the pressure was released, the spores were seeded on a ager medium, and incubated for one week and more longer at 25{sup 0}C with white light of 2000 lux. It was proved that 70-90% of the spores were alive and germinated after exposed to the maximum pressure of 7.5 GPa for up to 72 hours. However, after exposed to 7.5 GPa for 6 days, only 4 individuals in a hundred were germinated. The pressure tolerance of moss Venturiella is found to be stronger than a small animal, tardigrade.

  15. Microorganisms under high pressure--adaptation, growth and biotechnological potential.

    Science.gov (United States)

    Mota, Maria J; Lopes, Rita P; Delgadillo, Ivonne; Saraiva, Jorge A

    2013-12-01

    Hydrostatic pressure is a well-known physical parameter which is now considered an important variable of life, since organisms have the ability to adapt to pressure changes, by the development of resistance against this variable. In the past decades a huge interest in high hydrostatic pressure (HHP) technology is increasingly emerging among food and biosciences researchers. Microbial specific stress responses to HHP are currently being investigated, through the evaluation of pressure effects on biomolecules, cell structure, metabolic behavior, growth and viability. The knowledge development in this field allows a better comprehension of pressure resistance mechanisms acquired at sub-lethal pressures. In addition, new applications of HHP could arise from these studies, particularly in what concerns to biotechnology. For instance, the modulation of microbial metabolic pathways, as a response to different pressure conditions, may lead to the production of novel compounds with potential biotechnological and industrial applications. Considering pressure as an extreme life condition, this review intends to present the main findings so far reported in the scientific literature, focusing on microorganisms with the ability to withstand and to grow in high pressure conditions, whether they have innated or acquired resistance, and show the potential of the application of HHP technology for microbial biotechnology. © 2013.

  16. High frequency pressure oscillator for microcryocoolers

    NARCIS (Netherlands)

    Vanapalli, Srinivas; ter Brake, Hermanus J.M.; Jansen, Henricus V.; Zhao, Yiping; Holland, Herman J.; Burger, Johannes Faas; Elwenspoek, Michael Curt

    2008-01-01

    Microminiature pulse tube cryocoolers should operate at a frequency of an order higher than the conventional macro ones because the pulse tube cryocooler operating frequency scales inversely with the square of the pulse tube diameter. In this paper, the design and experiments of a high frequency

  17. High frequency pressure oscillator for microcryocoolers

    NARCIS (Netherlands)

    Vanapalli, Srinivas; ter Brake, Hermanus J.M.; Jansen, Henricus V.; Zhao, Yiping; Holland, Herman J.; Burger, Johannes Faas; Elwenspoek, Michael Curt

    2008-01-01

    Microminiature pulse tube cryocoolers should operate at a frequency of an order higher than the conventional macro ones because the pulse tube cryocooler operating frequency scales inversely with the square of the pulse tube diameter. In this paper, the design and experiments of a high frequency pre

  18. High frequency pressure oscillator for microcryocoolers

    NARCIS (Netherlands)

    Vanapalli, S.; Brake, ter H.J.M.; Jansen, H.V.; Zhao, Y.; Holland, H.J.; Burger, J.F.; Elwenspoek, M.C.

    2008-01-01

    Microminiature pulse tube cryocoolers should operate at a frequency of an order higher than the conventional macro ones because the pulse tube cryocooler operating frequency scales inversely with the square of the pulse tube diameter. In this paper, the design and experiments of a high frequency pre

  19. Experiments on aerosol removal by high-pressure water spray

    Energy Technology Data Exchange (ETDEWEB)

    Corno, Ada del, E-mail: delcorno@rse-web.it [RSE, Power Generation Technologies and Materials Dept, via Rubattino 54, I-20134 Milano (Italy); Morandi, Sonia, E-mail: morandi@rse-web.it [RSE, Power Generation Technologies and Materials Dept, via Rubattino 54, I-20134 Milano (Italy); Parozzi, Flavio, E-mail: parozzi@rse-web.it [RSE, Power Generation Technologies and Materials Dept, via Rubattino 54, I-20134 Milano (Italy); Araneo, Lucio, E-mail: lucio.araneo@polimi.it [Politecnico di Milano, Department of Energy, via Lambruschini 4A, I-20156 Milano (Italy); CNR-IENI, via Cozzi 53, I-20125 Milano (Italy); Casella, Francesco, E-mail: francesco2.casella@mail.polimi.it [Politecnico di Milano, Department of Energy, via Lambruschini 4A, I-20156 Milano (Italy)

    2017-01-15

    Highlights: • Experimental research to measure the efficiency of high-pressure sprays in capturing aerosols if applied to a filtered containment venting system in case of severe accident. • Cloud of monodispersed SiO{sub 2} particles with sizes 0.5 or 1.0 μm and initial concentration in the range 2–90 mg/m{sup 3}. • Carried out in a chamber 0.5 × 1.0 m and 1.5 m high, with transparent walls equipped with a high pressure water spray with single nozzle. • Respect to low-pressure sprays, removal efficiency turned out significant: the half-life for 1 μm particles with a removal high-pressure spray system is orders of magnitude shorter than that with a low-pressure sprays system. - Abstract: An experimental research was managed in the framework of the PASSAM European Project to measure the efficiency of high-pressure sprays in capturing aerosols when applied to a filtered containment venting system in case of severe accident. The campaign was carried out in a purposely built facility composed by a scrubbing chamber 0.5 × 1.0 m and 1.5 m high, with transparent walls to permit the complete view of the aerosol removal process, where the aerosol was injected to form a cloud of specific particle concentration. The chamber was equipped with a high pressure water spray system with a single nozzle placed on its top. The test matrix consisted in the combination of water pressure injections, in the range 50–130 bar, on a cloud of monodispersed SiO{sub 2} particles with sizes 0.5 or 1.0 μm and initial concentration ranging between 2 and 99 mg/m{sup 3}. The spray was kept running for 2 min and the efficiency of the removal was evaluated, along the test time, using an optical particle sizer. With respect to low-pressure sprays, the removal efficiency turned out much more significant: the half-life for 1 μm particles with a removal high-pressure spray system is orders of magnitude shorter than that with a low-pressure spray system. The highest removal rate was

  20. 老年女性腹型肥胖与血压昼夜节律及动脉僵硬度的关系%Relationship of abdominal obesity with circadian blood pressure rhythm and arterial stiffness in elderly women

    Institute of Scientific and Technical Information of China (English)

    许建超; 刘振东; 路方红; 刁玉涛; 张华; 赵颖馨; 孙尚文; 王舒建

    2014-01-01

    Objective To study the relationship of abdominal obesity with circadian blood pressure rhythm and arterial stiffness in elderly women .Methods Three hundred and fifty-three elderly women were divided into non-abdominal obesity group (n= 160) and abdominal obesity group (n=193)according to their waist circumference .Their carotid radial pulse wave velocity(crPWV) and 24 h ambulatory blood pressure were monitored .Results The non-dipper blood pressure , crPWV and symmetric AASI were significantly higher in abdominal obesity group than in non-abdominal obesity group (32 .6% vs 10 .0% ,11 .83 ± 1 .19 m/s vs 10 .90 ± 1 .04 m/s ,0 .31 ± 0 .15 vs 0 .24 ± 0 .17 ,P<0 .05) wile the nocturnal systolic and diastolic blood pressure were significantly lower in abdominal obesity group than in non-abdominal obesity group (P<0 .01) .Multiple linear regression analysis showed that waist circumference was the main risk factor for crPWV and sym-metric AASI after adjustment for age ,blood lipid and BMI (P<0 .05) .Logistic regression analysis revealed that abdominal obesity was the main risk factor for circadian blood pressure rhythm (OR=1 .104 ,95% CI:1 .074 -1 .134 ,P<0 .05) .Conclusion Abdominal fat deposit can signifi-cantly affect circadian blood pressure rhythm and arterial stiffness in elderly women .It is of great importance to control waist circumference in preventing arteriosclerosis .%目的:探讨老年女性腹型肥胖与血压昼夜节律及动脉僵硬度的关系。方法选择老年女性353例,根据腰围将受试者分为2组,即非腹型肥胖组160例,腹型肥胖组193例。所有受试者监测颈桡动脉脉搏波传导速度(crPWV)、24 h动态血压。结果腹型肥胖组非杓型血压(32.6% vs 10.0%)、crPWV [(11.83±1.19)m/s vs (10.90±1.04)m/s]、对称动态动脉硬化指数[(0.31±0.15) vs (0.24±0.17)]显著高于非腹型肥胖组,夜间收缩压下降率、夜间舒张压下降率显著

  1. Semicircular Canal Pressure Changes During High-intensity Acoustic Stimulation.

    Science.gov (United States)

    Maxwell, Anne K; Banakis Hartl, Renee M; Greene, Nathaniel T; Benichoux, Victor; Mattingly, Jameson K; Cass, Stephen P; Tollin, Daniel J

    2017-08-01

    Acoustic stimulation generates measurable sound pressure levels in the semicircular canals. High-intensity acoustic stimuli can cause hearing loss and balance disruptions. To examine the propagation of acoustic stimuli to the vestibular end-organs, we simultaneously measured fluid pressure in the cochlea and semicircular canals during both air- and bone-conducted sound presentation. Five full-cephalic human cadaveric heads were prepared bilaterally with a mastoidectomy and extended facial recess. Vestibular pressures were measured within the superior, lateral, and posterior semicircular canals, and referenced to intracochlear pressure within the scala vestibuli with fiber-optic pressure probes. Pressures were measured concurrently with laser Doppler vibrometry measurements of stapes velocity during stimulation with both air- and bone-conduction. Stimuli were pure tones between 100 Hz and 14 kHz presented with custom closed-field loudspeakers for air-conducted sounds and via commercially available bone-anchored device for bone-conducted sounds. Pressures recorded in the superior, lateral, and posterior semicircular canals in response to sound stimulation were equal to or greater in magnitude than those recorded in the scala vestibuli (up to 20 dB higher). The pressure magnitudes varied across canals in a frequency-dependent manner. High sound pressure levels were recorded in the semicircular canals with sound stimulation, suggesting that similar acoustical energy is transmitted to the semicircular canals and the cochlea. Since these intralabyrinthine pressures exceed intracochlear pressure levels, our results suggest that the vestibular end-organs may also be at risk for injury during exposure to high-intensity acoustic stimuli known to cause trauma in the auditory system.

  2. High Pressure Equation of State Studies Using Ethanol-Methanol And Argon As Pressure Medium

    Science.gov (United States)

    Godwal, B. K.; Speziale, S.; Clark, S.; Yan, J.; Jeanloz, R.

    2008-12-01

    Experimental high pressure studies are extremely important to planetary science, material science and to the development of condensed matter theory. With experimental difficulties in creating the extreme pressure temperature conditions appropriate to planetary interiors, the approach used is to obtain the thermodynamic data on materials of interest by extrapolating the condensed matter theory which has been benchmarked with the outcome of high pressure experiments to the available high pressures. However the high pressure data used to match the theory heavily depends on the use of pressure media; like ethanol-methanol, silicon oil, argon and helium. Unfortunately still there exist controversy in the literature even with the use of helium as pressure medium as illustrated by the unsettled debate on Zn and Os among different groups. We have measured the equation of state of intermetallic compound AuIn2 and Cd0.8Hg0.2 alloy using ethanol-methanol and argon to the pressure of 20 GPa to confirm the appearance of anomalies in the data due to occurrence of subtle electronic phase transitions. However these anomalies can also be attributed to oriented lattice strains and local non-hydrostatic conditions. We have tried to remove these at room temperature by stabilizing the sample in argon medium in the diamond anvil cell with proper annealing as indicated by the uniformity of the pressure across the sample by ruby fluorescence measurements. We will present the data revealing the electronic transition in AuIn2 at 2.7 GPa and in Cd0.8Hg0.2 near 9 and 18 GPa.

  3. Tolerance of budding yeast Saccharomyces cerevisiae to ultra high pressure

    Science.gov (United States)

    Shibata, M.; Torigoe, M.; Matsumoto, Y.; Yamamoto, M.; Takizawa, N.; Hada, Y.; Mori, Y.; Takarabe, K.; Ono, F.

    2014-05-01

    Our studies on the tolerance of plants and animals against very high pressure of several GPa have been extended to a smaller sized fungus, the budding yeast Saccharomyces cerevisiae. Several pieces of budding yeast (dry yeast) were sealed in a small teflon capsule with a liquid pressure medium fluorinate, and exposed to 7.5 GPa by using a cubic anvil press. The pressure was kept constant for various duration of time from 2 to 24 h. After the pressure was released, the specimens were brought out from the teflon capsule, and they were cultivated on a potato dextrose agar. It was found that the budding yeast exposed to 7.5 GPa for up to 6 h showed multiplication. However, those exposed to 7.5 GPa for longer than 12 h were found dead. The high pressure tolerance of budding yeast is a little weaker than that of tardigrades.

  4. The high-pressure compressibility of B12P2

    Science.gov (United States)

    Gao, Yang; Zhou, Mi; Wang, Haiyan; Ji, Cheng; Whiteley, C. E.; Edgar, J. H.; Liu, Haozhe; Ma, Yanzhang

    2017-03-01

    In situ high pressure synchrotron X-ray diffraction measurements were performed on icosahedral boron phosphide (B12P2) to 43.2 GPa. No structural phase transition occurs over this pressure range. The bulk modulus of B12P2 is KOT = 207 ± 7 GPa with pressure derivative of K'OT = 6.6 ± 0.8 . The structure is most compressible along the chain formed by phosphorus and boron atoms in the crystal structure. It is believed that the compressibility of boron-rich compounds at close to ambient pressure is determined by the boron icosahedral structure, while the inclusive atoms (both boron and non-boron) between the icosahedra determine the high-pressure compressibility and structure stability.

  5. A scanning fluorescence spectroscopy of decorin under high pressure

    Science.gov (United States)

    Komoda, Takahito; Kim, Yun-Jung; Suzuki, Atsushi; Nishiumi, Tadayuki

    2013-06-01

    High pressure processing is able to tenderize not only meat but also intramuscular connective tissue, which is mainly composed of collagen. Decorin, one of the proteoglycans, binds to and stabilizes collagen fibrils. It has been suggested that structural weakening of intramuscular connective tissue may result from the disappearance of the decorin-collagen interaction. In this study, the fluorescence spectra and the surface hydrophobicity of decorin molecules were measured under high pressure in order to examine the resulting change in the tertiary structure. The fluorescence intensity and the surface hydrophobicity of decorin molecules both decreased with increasing applied pressure and with applied time at the constant applied pressure, respectively. The observations indicate that the native structure of decorin is maintained during 200 MPa pressurization for less than 30 min.

  6. High pressure in semiconductor physics II

    CERN Document Server

    Willardson, R K; Suski, Tadeusz; Paul, William

    1998-01-01

    Since its inception in 1966, the series of numbered volumes known as Semiconductors and Semimetals has distinguished itself through the careful selection of well-known authors, editors, and contributors. The "Willardson and Beer" Series, as it is widely known, has succeeded in publishing numerous landmark volumes and chapters. Not only did many of these volumes make an impact at the time of their publication, but they continue to be well-cited years after their original release. Recently, Professor Eicke R. Weber of the University of California at Berkeley joined as a co-editor of the series. Professor Weber, a well-known expert in the field of semiconductor materials, will further contribute to continuing the series' tradition of publishing timely, highly relevant, and long-impacting volumes. Some of the recent volumes, such as Hydrogen in Semiconductors, Imperfections in III/V Materials, Epitaxial Microstructures, High-Speed Heterostructure Devices, Oxygen in Silicon, and others promise indeed that this tra...

  7. CARS Diagnostics of High Pressure Combustion.

    Science.gov (United States)

    1982-11-01

    single pulse spontaneous Raman scattering. Furthermore. in this ture increases, the band broadens as the rotational population distri- sooting flame , laser... sooting flame with height above the burner. S cm- the fine structure shown in Fig. 2 is lost, but the spectra Recently, the feasibility of CARS for...under adverse conditions, measurements in a highly important in such devices as gas turbines, internal sooting flame will be described (Ref. 3). BOXCARS

  8. High pressure differential conductance measurements of (Pb,Sn)Se

    Science.gov (United States)

    Paul, Tiffany; Vangennep, Derrick; Jackson, Daniel; Biswas, Amlan; Hamlin, James

    Topological transitions have been recognized as a new type of quantum phase transition. Recently, a number of papers have reported scanning tunneling microscope (STM) measurements of the Landau level spectra of topologically non-trivial materials. Such measurements can offer substantial insight into the nature of the transition between topologically distinct phases. Although applied pressure represents an attractive means to drive a topological quantum phase transition, STM measurements can not be performed under high pressure conditions. In this talk, I will discuss our recent attempts to observe Landau level spectra in compressed (Pb,Sn)Se using differential conductance measurements. Acknowledgements: TAP supported by REU NSF DMR-1461019. Pressure cell development and measurements at high magnetic fields supported by the National High Magnetic Field Laboratory User Collaboration Grants Program. Synthesis, characterization, and high pressure measurements supported by NSF DMR-1453752.

  9. The high pressure gas Cerenkov counter at the Omega Facility.

    CERN Multimedia

    1975-01-01

    The high-pressure gas Cerenkov was used to measure reactions as pion (or kaon)- hydrogen --> forward proton - X. It was built by the Ecole Polytechnique (Palaiseu). Here Peter Sonderegger and Patrick Fleury,

  10. Beam steering effects in turbulent high pressure flames

    Energy Technology Data Exchange (ETDEWEB)

    Hemmerling, B.; Kaeppeli, B. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-06-01

    The propagation of a laser beam through a flame is influenced by variations of the optical density. Especially in turbulent high pressure flames this may seriously limit the use of laser diagnostic methods. (author) 1 fig., 2 refs.

  11. The principles of ultra high pressure technology and its application ...

    African Journals Online (AJOL)

    The principles of ultra high pressure technology and its application in food processing/preservation: A review of ... African Journal of Biotechnology ... along the entire food chain, food preservation remains as necessary today as in the past.

  12. Novel High Pressure Pump-on-a-Chip Technology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — HJ Science & Technology, Inc proposes to develop a novel high pressure "pump-on-a-chip" and "valve-on-a-chip" microfluidic technology for NASA planetary science...

  13. The Combustion of HMX. [burning rate at high pressures

    Science.gov (United States)

    Boggs, T. L.; Price, C. F.; Atwood, A. I.; Zurn, D. E.; Eisel, J. L.

    1980-01-01

    The burn rate of HMX was measured at high pressures (p more than 1000 psi). The self deflagration rate of HMX was determined from 1 atmosphere to 50,000 psi. The burning rate shows no significant slope breaks.

  14. Scheelite CaWO{sub 4} at high pressures

    Energy Technology Data Exchange (ETDEWEB)

    Grzechnik, Andrzej [Laboratory of Crystallography, University of Bayreuth, D-95440 Bayreuth (Germany); Crichton, Wilson A [European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble cedex (France); Hanfland, Michael [European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble cedex (France); Smaalen, Sander van [Laboratory of Crystallography, University of Bayreuth, D-95440 Bayreuth (Germany)

    2003-11-05

    The high-pressure room-temperature behaviour of scheelite CaWO{sub 4} (I4{sub 1}/a,Z = 4) is studied using high-resolution synchrotron angle-dispersive x-ray powder diffraction in diamond anvil cells loaded with helium or a mixture of methanol and ethanol as the pressure-transmitting media. At about 10 GPa, there occurs a phase transition to the fergusonite type (I 2/a,Z = 4) without any discontinuity in the pressure dependence of the unit cell volumes. These observations are discussed in relation to the high-pressure-high-temperature systematics of the AMX{sub 4} and AX{sub 2} type compounds.

  15. Deformation Twinning of a Silver Nanocrystal under High Pressure

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Xiaojing; Yang, Wenge; Harder, Ross; Sun, Yugang; Liu, Ming; Chu, Yong S.; Robinson, Ian K.; Mao, Ho-kwang

    2015-11-01

    Within a high-pressure environment, crystal deformation is controlled by complex processes such as dislocation motion, twinning, and phase transitions, which change materials' microscopic morphology and alter their properties. Understanding a crystal's response to external stress provides a unique opportunity for rational tailoring of its functionalities. It is very challenging to track the strain evolution and physical deformation from a single nanoscale crystal under high-pressure stress. Here, we report an in situ three-dimensional mapping of morphology and strain evolutions in a single-crystal silver nanocube within a high-pressure environment using the Bragg Coherent Diffractive Imaging (CDI) method. We observed a continuous lattice distortion, followed by a deformation twining process at a constant pressure. The ability to visualize stress-introduced deformation of nanocrystals with high spatial resolution and prominent strain sensitivity provides an important route for interpreting and engineering novel properties of nanomaterials.

  16. High-Pressure Design of Advanced BN-Based Materials.

    Science.gov (United States)

    Kurakevych, Oleksandr O; Solozhenko, Vladimir L

    2016-10-20

    The aim of the present review is to highlight the state of the art in high-pressure design of new advanced materials based on boron nitride. Recent experimental achievements on the governing phase transformation, nanostructuring and chemical synthesis in the systems containing boron nitride at high pressures and high temperatures are presented. All these developments allowed discovering new materials, e.g., ultrahard nanocrystalline cubic boron nitride (nano-cBN) with hardness comparable to diamond, and superhard boron subnitride B13N₂. Thermodynamic and kinetic aspects of high-pressure synthesis are described based on the data obtained by in situ and ex situ methods. Mechanical and thermal properties (hardness, thermoelastic equations of state, etc.) are discussed. New synthetic perspectives, combining both soft chemistry and extreme pressure-temperature conditions are considered.

  17. How Potassium Can Help Control High Blood Pressure

    Science.gov (United States)

    ... natural sources of potassium. For example, a medium banana has about 420 mg of potassium and half ... high blood pressure. Learn more Get a fact sheet on following a heart-healthy diet: English | Spanish ...

  18. Abdominal Aortic Aneurysm (AAA)

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Abdominal Aortic Aneurysm (AAA) Abdominal aortic aneurysm (AAA) occurs when atherosclerosis ... an abdominal aortic aneurysm treated? What is an abdominal aortic aneurysm? The aorta, the largest artery in the body, ...

  19. Chicken lines divergent for low or high abdominal fat deposition: a relevant model to study the regulation of energy metabolism.

    Science.gov (United States)

    Baéza, E; Le Bihan-Duval, E

    2013-06-01

    Divergent selection of chickens for low or high abdominal fat (AF) but similar BW at 63 days of age was undertaken in 1977. The selection programme was conducted over seven successive generations. The difference between lines was then maintained constant at about twice the AF in the fat line as in the lean line. The aims of the first studies on these divergent chicken lines were to describe the growth, body composition and reproductive performance in young and adult birds. The lines were then used to improve the understanding of the relationship between fatness and energy and protein metabolism in the liver, muscle and adipose tissues, as well as the regulation of such metabolism at hormonal, gene and hypothalamic levels. The effects on muscle energy metabolism in relation to meat quality parameters were also described. This paper reviews the main results obtained with these lines.

  20. A Generalized Equation of State for High-Pressure Liquids

    Institute of Scientific and Technical Information of China (English)

    LIANG Yan-bo; TONG Jing-shan

    2005-01-01

    An equation of state (EOS) for high-pressure liquids, I.e., Tait EOS, is deduced according to isothermal compressibility KT=-1/V·((а)V/(а)p)T·.Based on the equation, a generalized EOS for high pressure-liquids is established by using the reduced state principle and introducing a characteristic parameter-configuration factorξ.Reasonably satisfactory P-V-T data for many organic compounds, including some polar components, were calculated by using the equation.

  1. Synthesis of an orthorhombic high pressure boron phase

    Science.gov (United States)

    Zarechnaya, Evgeniya Yu; Dubrovinsky, Leonid; Dubrovinskaia, Natalia; Miyajima, Nobuyoshi; Filinchuk, Yaroslav; Chernyshov, Dmitry; Dmitriev, Vladimir

    2008-12-01

    The densest boron phase (2.52 g cm-3) was produced as a result of the synthesis under pressures above 9 GPa and temperatures up to ~1800 °C. The x-ray powder diffraction pattern and the Raman spectra of the new material do not correspond to those of any known boron phases. A new high-pressure high-temperature boron phase was defined to have an orthorhombic symmetry (Pnnm (No. 58)) and 28 atoms per unit cell.

  2. Effect of high pressure on physicochemical properties of meat.

    Science.gov (United States)

    Buckow, Roman; Sikes, Anita; Tume, Ron

    2013-01-01

    The application of high pressure offers some interesting opportunities in the processing of muscle-based food products. It is well known that high-pressure processing can prolong the shelf life of meat products in addition to chilling but the pressure-labile nature of protein systems limits the commercial range of applications. High pressure can affect the texture and gel-forming properties of myofibrillar proteins and, hence, has been suggested as a physical and additive-free alternative to tenderize and soften or restructure meat and fish products. However, the rate and magnitude at which pressure and temperature effects take place in muscles are variable and depend on a number of circumstances and conditions that are still not precisely known. This review provides an overview of the current knowledge of the effects of high pressure on muscle tissue over a range of temperatures as it relates to meat texture, microstructure, color, enzymes, lipid oxidation, and pressure-induced gelation of myofibrillar proteins.

  3. High-pressure-low-temperature x-ray power diffractometer.

    Science.gov (United States)

    Syassen, K; Holzapfel, W B

    1978-08-01

    A high-pressure technique for x-ray diffraction studies at low temperatures is described. The system consists of a Bridgman anvil type high-pressure device with either tungsten carbide or boron carbide anvils, a liquid He cryostat, and x-ray diffractometer operating in Debye-Scherrer geometry. The newly developed boron carbide anvil cell is capable of containing a liquid pressure transmitting medium. The precision of the lattice parameter determination is discussed and the effect of nonisostatic stress components on the diffraction pattern is examined.

  4. High pressure and multiferroics materials: a happy marriage

    Science.gov (United States)

    Gilioli, Edmondo; Ehm, Lars

    2014-01-01

    The community of material scientists is strongly committed to the research area of multiferroic materials, both for the understanding of the complex mechanisms supporting the multiferroism and for the fabrication of new compounds, potentially suitable for technological applications. The use of high pressure is a powerful tool in synthesizing new multiferroic, in particular magneto-electric phases, where the pressure stabilization of otherwise unstable perovskite-based structural distortions may lead to promising novel metastable compounds. The in situ investigation of the high-pressure behavior of multiferroic materials has provided insight into the complex interplay between magnetic and electronic properties and the coupling to structural instabilities. PMID:25485138

  5. Very high pressure Moessbauer spectroscopy using diamond anvil cells

    Energy Technology Data Exchange (ETDEWEB)

    Pasternak, M.P.; Taylor, R.D.

    1988-01-01

    The technique of generating very high pressure by means of Diamond Anvil Cells (DAC) for Mossbauer Effect applications is outlined. A comprehensive description is presented of the principles of DAC, modification for the use in M/umlt o/ssbauer Spectroscopy (MS), the Merrill--Bassett and Bassett cells, of pressure measurements, of gasketing and collimation, and of hydrostatic media. Examples of /sup 151/Eu, /sup 119/Sn and /sup 129/I are given showing the feasibility of DAC applications in MS. Other isotopes with potential use for high pressure MS using DAC are suggested. 27 refs., 9 figs.

  6. High pressure and multiferroics materials: a happy marriage.

    Science.gov (United States)

    Gilioli, Edmondo; Ehm, Lars

    2014-11-01

    The community of material scientists is strongly committed to the research area of multiferroic materials, both for the understanding of the complex mechanisms supporting the multiferroism and for the fabrication of new compounds, potentially suitable for technological applications. The use of high pressure is a powerful tool in synthesizing new multiferroic, in particular magneto-electric phases, where the pressure stabilization of otherwise unstable perovskite-based structural distortions may lead to promising novel metastable compounds. The in situ investigation of the high-pressure behavior of multiferroic materials has provided insight into the complex interplay between magnetic and electronic properties and the coupling to structural instabilities.

  7. High pressure and multiferroics materials: a happy marriage

    Directory of Open Access Journals (Sweden)

    Edmondo Gilioli

    2014-11-01

    Full Text Available The community of material scientists is strongly committed to the research area of multiferroic materials, both for the understanding of the complex mechanisms supporting the multiferroism and for the fabrication of new compounds, potentially suitable for technological applications. The use of high pressure is a powerful tool in synthesizing new multiferroic, in particular magneto-electric phases, where the pressure stabilization of otherwise unstable perovskite-based structural distortions may lead to promising novel metastable compounds. The in situ investigation of the high-pressure behavior of multiferroic materials has provided insight into the complex interplay between magnetic and electronic properties and the coupling to structural instabilities.

  8. High-pressure studies of cyclohexane to 40 GPa.

    Science.gov (United States)

    Pravica, Michael; Shen, Yongrong; Quine, Zachary; Romano, Edward; Hartnett, David

    2007-04-26

    We present data from two room temperature synchrotron X-ray powder diffraction studies of cyclohexane up to approximately 40 and approximately 20 GPa. In the first experiment, pressure cycling was employed wherein pressure was varied up to approximately 16 GPa, reduced to 3.5 GPa, and then raised again to 40 GPa. Initially, the sample was found to be in the monoclinic phase (P12(1)/n1) at approximately 8.4 GPa. Beyond this pressure, the sample adopted triclinic unit cell symmetry (P1) which remained so even when the pressure was reduced to 3.5 GPa, indicating significant hysteresis and metastability. In the second experiment, pressure was more slowly varied, and the monoclinic unit cell structure (P12(1)/n1) was observed at lower pressures up to approximately 7 GPa, above which a phase transformation into the P1 triclinic unit cell symmetry occurred. Thus, the pressure onset of the triclinic phase may be dependent upon the pressurizing conditions. High-pressure Raman data that further emphasize a phase transition (probably into phase VI) around 10 GPa are also presented. We also have further evidence for a phase VII, which is probably triclinic.

  9. Energy Limits in Second Generation High-pitch Dual Source CT - Comparison in an Upper Abdominal Phantom

    Directory of Open Access Journals (Sweden)

    Martin Beeres

    2015-01-01

    Full Text Available Objectives: The aim of our study was to find out how much energy is applicable in second-generation dual source high-pitch computed tomography (CT in imaging of the abdomen. Materials and Methods: We examined an upper abdominal phantom using a Somatom Definition Flash CT-Scanner (Siemens, Forchheim, Germany. The study protocol consisted of a scan-series at 100 kV and 120 kV. In each scan series we started with a pitch of 3.2 and reduced it in steps of 0.2, until a pitch of 1.6 was reached. The current was adjusted to the maximum the scanner could achieve. Energy values, image noise, image quality, and radiation exposure were evaluated. Results: For a pitch of 3.2 the maximum applicable current was 142 mAs at 120 kV and in 100 kV the maximum applicable current was 114 mAs. For conventional abdominal imaging, current levels of 200 to 260 mAs are generally used. To achieve similar current levels, we had to decrease the pitch to 1.8 at 100 kV - at this pitch we could perform our imaging at 204 mAs. At a pitch of 2.2 in 120 kV we could apply a current of 206 mAs. Conclusion: We conclude our study by stating that if there is a need for a higher current, we have to reduce the pitch. In a high-pitch dual source CT, we always have to remember where our main focus is, so we can adjust the pitch to the energy we need in the area of the body that has to be imaged, to find answers to the clinical question being raised.

  10. High-pressure crystallography of periodic and aperiodic crystals.

    Science.gov (United States)

    Hejny, Clivia; Minkov, Vasily S

    2015-03-01

    More than five decades have passed since the first single-crystal X-ray diffraction experiments at high pressure were performed. These studies were applied historically to geochemical processes occurring in the Earth and other planets, but high-pressure crystallography has spread across different fields of science including chemistry, physics, biology, materials science and pharmacy. With each passing year, high-pressure studies have become more precise and comprehensive because of the development of instrumentation and software, and the systems investigated have also become more complicated. Starting with crystals of simple minerals and inorganic compounds, the interests of researchers have shifted to complicated metal-organic frameworks, aperiodic crystals and quasicrystals, molecular crystals, and even proteins and viruses. Inspired by contributions to the microsymposium 'High-Pressure Crystallography of Periodic and Aperiodic Crystals' presented at the 23rd IUCr Congress and General Assembly, the authors have tried to summarize certain recent results of single-crystal studies of molecular and aperiodic structures under high pressure. While the selected contributions do not cover the whole spectrum of high-pressure research, they demonstrate the broad diversity of novel and fascinating results and may awaken the reader's interest in this topic.

  11. Hydrogen Storage in Mesoporous Materials under High Pressure

    Science.gov (United States)

    Weinberger, Michelle; Somayazulu, Maddury; Hemley, Russell

    2008-03-01

    To date, the materials considered best candidates for hydrogen storage fuel cells include activated carbon and metal organic frameworks. Both very high surface area activated carbon and MOF-5 have been shown to adsorb around 4.5 wt % of hydrogen gas at 78 K. We have investigated the fundamental structural response of these materials to high pressure, as well as their behavior at high pressure when packed with dense hydrogen. Further investigation of these materials at low temperatures while still at elevated pressures may in fact provide a route for recovery of these hydrogen-packed materials to near ambient conditions. Covalent organic frameworks offer the potential for even better hydrogen storage capacity. These materials have significantly lower densities than the MOF materials and offer a significantly larger number of adsorption sites. Diamond anvil cells are uniquely suited for the study of these materials, allowing in situ measurements at high pressure as well as at low temperatures. Using X-ray diffraction and Raman spectroscopy and Infrared Spectroscopy we probe the behavior of the hydrogen confined in these porous materials at high pressure by tracking changes in the in situ high pressure x-ray diffraction patterns and shifts in the hydrogen vibron peaks.

  12. Advances and synergy of high pressure sciences at synchrotron sources

    Energy Technology Data Exchange (ETDEWEB)

    Liu, H.; Ehm, L.; Duffy, T.; Crichton, W.; Aoki, K.

    2009-01-01

    Introductory overview to the special issue papers on high-pressure sciences and synchrotron radiation. High-pressure research in geosciences, materials science and condensed matter physics at synchrotron sources is experiencing growth and development through synergistic efforts around the world. A series of high-pressure science workshops were organized in 2008 to highlight these developments. One of these workshops, on 'Advances in high-pressure science using synchrotron X-rays', was held at the National Synchrotron Light Source (NSLS), Brookhaven National Laboratory, USA, on 4 October 2008. This workshop was organized in honour of Drs Jingzhu Hu and Quanzhong Guo in celebration of their retirement after up to 18 years of dedicated service to the high-pressure community as beamline scientists at X17 of NSLS. Following this celebration of the often unheralded role of the beamline scientist, a special issue of the Journal of Synchrotron Radiation on Advances and Synergy of High-Pressure Sciences at Synchrotron Sources was proposed, and we were pleased to invite contributions from colleagues who participated in the workshop as well as others who are making similar efforts at synchrotron sources worldwide.

  13. High-pressure crystallography of periodic and aperiodic crystals

    Directory of Open Access Journals (Sweden)

    Clivia Hejny

    2015-03-01

    Full Text Available More than five decades have passed since the first single-crystal X-ray diffraction experiments at high pressure were performed. These studies were applied historically to geochemical processes occurring in the Earth and other planets, but high-pressure crystallography has spread across different fields of science including chemistry, physics, biology, materials science and pharmacy. With each passing year, high-pressure studies have become more precise and comprehensive because of the development of instrumentation and software, and the systems investigated have also become more complicated. Starting with crystals of simple minerals and inorganic compounds, the interests of researchers have shifted to complicated metal–organic frameworks, aperiodic crystals and quasicrystals, molecular crystals, and even proteins and viruses. Inspired by contributions to the microsymposium `High-Pressure Crystallography of Periodic and Aperiodic Crystals' presented at the 23rd IUCr Congress and General Assembly, the authors have tried to summarize certain recent results of single-crystal studies of molecular and aperiodic structures under high pressure. While the selected contributions do not cover the whole spectrum of high-pressure research, they demonstrate the broad diversity of novel and fascinating results and may awaken the reader's interest in this topic.

  14. Advanced High-Temperature, High-Pressure Transport Reactor Gasification

    Energy Technology Data Exchange (ETDEWEB)

    Michael L. Swanson

    2005-08-30

    50 hours of gasification on a petroleum coke from the Hunt Oil Refinery and an additional 73 hours of operation on a high-ash coal from India. Data from these tests indicate that while acceptable fuel gas heating value was achieved with these fuels, the transport gasifier performs better on the lower-rank feedstocks because of their higher char reactivity. Comparable carbon conversions have been achieved at similar oxygen/coal ratios for both air-blown and oxygen-blown operation for each fuel; however, carbon conversion was lower for the less reactive feedstocks. While separation of fines from the feed coals is not needed with this technology, some testing has suggested that feedstocks with higher levels of fines have resulted in reduced carbon conversion, presumably due to the inability of the finer carbon particles to be captured by the cyclones. These data show that these low-rank feedstocks provided similar fuel gas heating values; however, even among the high-reactivity low-rank coals, the carbon conversion did appear to be lower for the fuels (brown coal in particular) that contained a significant amount of fines. The fuel gas under oxygen-blown operation has been higher in hydrogen and carbon dioxide concentration since the higher steam injection rate promotes the water-gas shift reaction to produce more CO{sub 2} and H{sub 2} at the expense of the CO and water vapor. However, the high water and CO{sub 2} partial pressures have also significantly reduced the reaction of (Abstract truncated)

  15. High blood pressure in older subjects with cognitive impairment.

    Science.gov (United States)

    Mossello, Enrico; Simoni, David

    2016-06-22

    High blood pressure and cognitive impairment often coexist in old age, but their pathophysiological association is complex. Several longitudinal studies have shown that high blood pressure at midlife is a risk factor for cognitive impairment and dementia, although this association is much less clear in old age. The effect of blood pressure lowering in reducing the risk of dementia is only borderline significant in clinical trials of older subjects, partly due to the insufficient follow-up time. Conversely, dementia onset is associated with a decrease of blood pressure values, probably secondary to neurodegeneration. Prognostic effect of blood pressure values in cognitively impaired older subjects is still unclear, with aggressive blood pressure lowering being potentially harmful in this patients category. Brief cognitive screening, coupled with simple motor assessment, are warranted to identify frail older subjects who need a more cautious approach to antihypertensive treatment. Values obtained with ambulatory blood pressure monitoring seem more useful than clinical ones to predict the outcome of cognitively impaired older subjects. Future studies should identify the most appropriate blood pressure targets in older subjects with cognitive impairment.

  16. High pressure-sensitive gene expression in Lactobacillus sanfranciscensis

    Directory of Open Access Journals (Sweden)

    R.F. Vogel

    2005-08-01

    Full Text Available Lactobacillus sanfranciscensis is a Gram-positive lactic acid bacterium used in food biotechnology. It is necessary to investigate many aspects of a model organism to elucidate mechanisms of stress response, to facilitate preparation, application and performance in food fermentation, to understand mechanisms of inactivation, and to identify novel tools for high pressure biotechnology. To investigate the mechanisms of the complex bacterial response to high pressure we have analyzed changes in the proteome and transcriptome by 2-D electrophoresis, and by microarrays and real time PCR, respectively. More than 16 proteins were found to be differentially expressed upon high pressure stress and were compared to those sensitive to other stresses. Except for one apparently high pressure-specific stress protein, no pressure-specific stress proteins were found, and the proteome response to pressure was found to differ from that induced by other stresses. Selected pressure-sensitive proteins were partially sequenced and their genes were identified by reverse genetics. In a transcriptome analysis of a redundancy cleared shot gun library, about 7% of the genes investigated were found to be affected. Most of them appeared to be up-regulated 2- to 4-fold and these results were confirmed by real time PCR. Gene induction was shown for some genes up-regulated at the proteome level (clpL/groEL/rbsK, while the response of others to high hydrostatic pressure at the transcriptome level seemed to differ from that observed at the proteome level. The up-regulation of selected genes supports the view that the cell tries to compensate for pressure-induced impairment of translation and membrane transport.

  17. CORRELATIONS BETWEEN BLOOD PRESSURE AND BODY WEIGHT, SERUM LEPTIN IN HIGH CALORIE DIET-INDUCED OBESE RATS

    Institute of Scientific and Technical Information of China (English)

    Hu Zhi; Ma Aiqun; Yang Chun; Tian Hongyan

    2006-01-01

    Objective To examine the change of body weight (BW) and blood pressure (BP) in obese rats, clarify relationships between BP and BW and other factors. Methods Male Spraque-Dawley rats were fed either with normal diet (ND) or high calorie diet (HC) for 20 weeks. BW and BP of tail artery were observed biweekly and tetraweekly respectively; serum leptin and fasting insulin (FINS) were detected by enzyme-linked immunoadsordent assay (ELISA) and radioimmunoassay (RIA) respectively. Fasting plasma glucose (FPG) and free fatty acid(FFA) were measured by conventional means. Results BW, abdominal fat weight (AFW), ratio of abdominal fat weight to body weight (RF/W), systolic blood pressure (SBP), diastolic blood pressure (DBP), serum levels of leptin and FINS, FPG, FFA increased in the HD group after 20 weeks diet intervention (P<0.05 or P<0.01). SBP was strongly correlated with BW, leptin, FINS and FFA (P<0.05), DBP was correlated with FFA (r=0.47, P<0.05). In addition, leptin was positively correlated with BW, AFW, RF/W, FINS and FFA (P<0.05 or P<0.01). Conclusion In this study of high calorie-diet induced rats, the gain of BW is accompanied by increased BP. The obese rats have hyperleptinemia, hyperinsulinemia, hyperglycemia and dyslipidemia which may have important effects on the development of obesity-related hypertension. RF/W is the key factor in which affect serum leptin level.

  18. Aqueous Geochemistry at High Pressures and High Temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Bass, Jay D. [Univ. of Illinois, Urbana-Champaign, IL (United States)

    2015-05-21

    This project is aimed at experimental characterization of the sound velocities, equations of state (EOS), and derived physical and chemical properties of aqueous solutions and carbon dioxide at extreme pressure and temperature conditions relevant to processes occurring in the interior of the Earth. Chemical transport, phase changes (including melting), fluid-solid reactions, and formation of magmatic liquids at convergent plat boundaries are a key motivation for this project. Research in this area has long been limited by the extreme experimental challenges and lack of data under the appropriate pressure-temperature (P-T) conditions. The vast majority of studies of aqueous geochemistry relevant to terrestrial problems of fluid-rock interactions have been conducted at 0.3 GPa or less, and the widely used Helgeson-Kirkham-Flowers equation of state for aqueous species is applicable only at ~ < 0.5 GPa. These limits are unfortunate because fluid flow and reactions plays a central role in many deeper environments. Recent efforts including our own, have resulted in new experimental techniques that now make it possible to investigate properties of homogeneous and heterogeneous equilibria involving aqueous species and minerals over a much broader range of pressure and temperature appropriate for deep crustal and upper mantle processes involving water-rich fluids. We carried out 1) Brillouin scattering measurements of the equations of state and molar volume of water and carbon dioxide to over 10 GPa and 870K using precise resistance heating of samples under pressure in the diamond anvil cell, and 2) the phase diagrams of the water and CO2, and 3) Exploring new experimental approaches, including CO2 laser heating of samples in a diamond cell, to measurements of sound velocities, EOS, and phase relations by Brillouin scattering to far greater pressures and temperatures.

  19. Electrical Resistivity and Thermodynamic Properties of Iron Under High Pressure

    Science.gov (United States)

    Hieu, Ho Khac; Hai, Tran Thi; Hong, Nguyen Thi; Sang, Ngo Dinh; Tuyen, Nguyen Viet

    2017-03-01

    In this work, the electrical resistivity and thermodynamic properties of iron under high pressure have been investigated by using the semi-empirical approach. The recently well-established Grüneisen parameter expressions have been applied to derive the Debye frequency and temperature under compression. Using these results combined with the Bloch-Grüneisen law, the resistivity of iron has also been determined up to Earth's core pressures. We show that the electrical resistivity diminished gradually with pressure and saturates at high pressure. Our model gives low electrical resistivity values which are in agreement with the recent experimental measurements. The low resistivity may be attributed to the well-known resistivity saturation effect at high temperature, which was not considered in earlier models of core conductivity.

  20. Chemical Vapor Deposition at High Pressure in a Microgravity Environment

    Science.gov (United States)

    McCall, Sonya; Bachmann, Klaus; LeSure, Stacie; Sukidi, Nkadi; Wang, Fuchao

    1999-01-01

    In this paper we present an evaluation of critical requirements of organometallic chemical vapor deposition (OMCVD) at elevated pressure for a channel flow reactor in a microgravity environment. The objective of using high pressure is to maintain single-phase surface composition for materials that have high thermal decomposition pressure at their optimum growth temperature. Access to microgravity is needed to maintain conditions of laminar flow, which is essential for process analysis. Based on ground based observations we present an optimized reactor design for OMCVD at high pressure and reduced gravity. Also, we discuss non-intrusive real-time optical monitoring of flow dynamics coupled to homogeneous gas phase reactions, transport and surface processes. While suborbital flights may suffice for studies of initial stages of heteroepitaxy experiments in space are essential for a complete evaluation of steady-state growth.