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Sample records for attenuates load-induced left

  1. MEF2C silencing attenuates load-induced left ventricular hypertrophy by modulating mTOR/S6K pathway in mice.

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    Ana Helena M Pereira

    Full Text Available BACKGROUND: The activation of the members of the myocyte enhancer factor-2 family (MEF2A, B, C and D of transcription factors promotes cardiac hypertrophy and failure. However, the role of its individual components in the pathogenesis of cardiac hypertrophy remains unclear. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we investigated whether MEF2C plays a role in mediating the left ventricular hypertrophy by pressure overload in mice. The knockdown of myocardial MEF2C induced by specific small interfering RNA (siRNA has been shown to attenuate hypertrophy, interstitial fibrosis and the rise of ANP levels in aortic banded mice. We detected that the depletion of MEF2C also results in lowered levels of both PGC-1alpha and mitochondrial DNA in the overloaded left ventricle, associated with enhanced AMP:ATP ratio. Additionally, MEF2C depletion was accompanied by defective activation of S6K in response to pressure overload. Treatment with the amino acid leucine stimulated S6K and suppressed the attenuation of left ventricular hypertrophy and fibrosis in the aforementioned aortic banded mice. CONCLUSION/SIGNIFICANCE: These findings represent new evidences that MEF2C depletion attenuates the hypertrophic responses to mechanical stress and highlight the potential of MEF2C to be a target for new therapies to cardiac hypertrophy and failure.

  2. Myocardial connective tissue growth factor (CCN2/CTGF attenuates left ventricular remodeling after myocardial infarction.

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    Jørgen Gravning

    Full Text Available AIMS: Myocardial CCN2/CTGF is induced in heart failure of various etiologies. However, its role in the pathophysiology of left ventricular (LV remodeling after myocardial infarction (MI remains unresolved. The current study explores the role of CTGF in infarct healing and LV remodeling in an animal model and in patients admitted for acute ST-elevation MI. METHODS AND RESULTS: Transgenic mice with cardiac-restricted overexpression of CTGF (Tg-CTGF and non-transgenic littermate controls (NLC were subjected to permanent ligation of the left anterior descending coronary artery. Despite similar infarct size (area of infarction relative to area at risk 24 hours after ligation of the coronary artery in Tg-CTGF and NLC mice, Tg-CTGF mice disclosed smaller area of scar tissue, smaller increase of cardiac hypertrophy, and less LV dilatation and deterioration of LV function 4 weeks after MI. Tg-CTGF mice also revealed substantially reduced mortality after MI. Remote/peri-infarct tissue of Tg-CTGF mice contained reduced numbers of leucocytes, macrophages, and cells undergoing apoptosis as compared with NLC mice. In a cohort of patients with acute ST-elevation MI (n = 42 admitted to hospital for percutaneous coronary intervention (PCI serum-CTGF levels (s-CTGF were monitored and related to infarct size and LV function assessed by cardiac MRI. Increase in s-CTGF levels after MI was associated with reduced infarct size and improved LV ejection fraction one year after MI, as well as attenuated levels of CRP and GDF-15. CONCLUSION: Increased myocardial CTGF activities after MI are associated with attenuation of LV remodeling and improved LV function mediated by attenuation of inflammatory responses and inhibition of apoptosis.

  3. Miso (Japanese soybean paste) soup attenuates salt-induced sympathoexcitation and left ventricular dysfunction in mice with chronic pressure overload.

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    Ito, Koji; Hirooka, Yoshitaka; Sunagawa, Kenji

    2014-02-01

    The hypothalamic mineralocorticoid receptor (MR)-angiotensin II type 1 receptor (AT1R) pathway is activated in mice with chronic pressure overload (CPO). When this activation is combined with high salt intake, it leads to sympathoexcitation, hypertension, and left ventricular (LV) dysfunction. Salt intake is thus an important factor that contributes to heart failure. Miso, a traditional Japanese food made from fermented soybeans, rice, wheat, or oats, can attenuate salt-induced hypertension in rats. However, its effects on CPO mice with salt-induced sympathoexcitation and LV dysfunction are unclear. Here, we investigated whether miso has protective effects in these mice. We also evaluated mechanisms associated with the hypothalamic MR-AT1R pathway. Aortic banding was used to produce CPO, and a sham operation was performed for controls. At 2 weeks after surgery, the mice were given water containing high NaCl levels (0.5%, 1.0%, and 1.5%) for 4 weeks. The high salt loading in CPO mice increased excretion of urinary norepinephrine (uNE), a marker of sympathetic activity, in an NaCl concentration-dependent manner; however, this was not observed in Sham mice. Subsequently, CPO mice were administered 1.0% NaCl water (CPO-H) or miso soup (1.0% NaCl equivalent, CPO-miso). The expression of hypothalamic MR, serum glucocorticoid-induced kinase-1 (SGK-1), and AT1R was higher in the CPO-H mice than in the Sham mice; however, the expression of these proteins was attenuated in the CPO-miso group. Although the CPO-miso mice had higher sodium intake, salt-induced sympathoexcitation was lower in these mice than in the CPO-H group. Our findings indicate that regular intake of miso soup attenuates salt-induced sympathoexcitation in CPO mice via inhibition of the hypothalamic MR-AT1R pathway. PMID:24908908

  4. Tissue transglutaminase is involved in mechanical load-induced osteogenic differentiation of human ligamentum flavum cells.

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    Chao, Yuan-Hung; Huang, Shih-Yung; Yang, Ruei-Cheng; Sun, Jui-Sheng

    2016-07-01

    Mechanical load-induced osteogenic differentiation might be the key cellular event in the calcification and ossification of ligamentum flavum. The aim of this study was to investigate the influence of tissue transglutaminase (TGM2) on mechanical load-induced osteogenesis of ligamentum flavum cells. Human ligamentum flavum cells were obtained from 12 patients undergoing lumbar spine surgery. Osteogenic phenotypes of ligamentum flavum cells, such as alkaline phosphatase (ALP), Alizarin red-S stain, and gene expression of osteogenic makers were evaluated following the administration of mechanical load and BMP-2 treatment. The expression of TGM2 was evaluated by real-time PCR, Western blotting, and enzyme-linked immunosorbent assay (ELISA) analysis. Our results showed that mechanical load in combination with BMP-2 enhanced calcium deposition and ALP activity. Mechanical load significantly increased ALP and OC gene expression on day 3, whereas BMP-2 significantly increased ALP, OPN, and Runx2 on day 7. Mechanical load significantly induced TGM2 gene expression and enzyme activity in human ligamentum flavum cells. Exogenous TGM2 increased ALP and OC gene expression; while, inhibited TG activity significantly attenuated mechanical load-induced and TGM2-induced ALP activity. In summary, mechanical load-induced TGM2 expression and enzyme activity is involved in the progression of the calcification of ligamentum flavum.

  5. Effect of obesity reduction on preservation of heart function and attenuation of left ventricular remodeling, oxidative stress and inflammation in obese mice

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    Wang Hui-Ting

    2012-07-01

    Full Text Available Abstract Background Obesity is an important cardiovascular risk factor. This study tested the effect of obesity reduction on preserving left ventricular ejection fraction (LVEF and attenuating inflammation, oxidative stress and LV remodeling in obese mice. Methods and results Eight-week-old C57BL/6 J mice (n=24 were equally divided into control (fed a control diet for 22 weeks, obesity (high-fat diet, 22 weeks, and obese reduction (OR (high-fat diet, 14 weeks; then control diet, 8 weeks. Animals were sacrificed at post 22-week high-fat diet and the LV myocardium collected. Heart weight, body weight, abdominal-fat weight, total cholesterol level and fasting blood glucose were higher in obesity than in control and OR (all p Conclusion Impaired LVEF, enhanced LV remodeling, inflammation, fibrosis, oxidative stress and apoptosis were reversed by reduction in mouse obesity.

  6. Chronic treatment with metformin suppresses toll-like receptor 4 signaling and attenuates left ventricular dysfunction following myocardial infarction.

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    Soraya, Hamid; Clanachan, Alexander S; Rameshrad, Maryam; Maleki-Dizaji, Nasrin; Ghazi-Khansari, Mahmoud; Garjani, Alireza

    2014-08-15

    Acute treatment with metformin has a protective effect in myocardial infarction by suppression of inflammatory responses due to activation of AMP-activated protein kinase (AMPK). In the present study, the effect of chronic pre-treatment with metformin on cardiac dysfunction and toll-like receptor 4 (TLR4) activities following myocardial infarction and their relation with AMPK were assessed. Male Wistar rats were randomly assigned to one of 5 groups (n=6): normal control and groups were injected isoproterenol after chronic pre-treatment with 0, 25, 50, or 100mg/kg of metformin twice daily for 14 days. Isoproterenol (100mg/kg) was injected subcutaneously on the 13th and 14th days to induce acute myocardial infarction. Isoproterenol alone decreased left ventricular systolic pressure and myocardial contractility indexed as LVdp/dtmax and LVdp/dtmin. The left ventricular dysfunction was significantly lower in the groups treated with 25 and 50mg/kg of metformin. Metfromin markedly lowered isoproterenol-induced elevation in the levels of TLR4 mRNA, myeloid differentiation protein 88 (MyD88), tumor necrosis factor-alpha (TNF-α), and interleukin 6 (IL-6) in the heart tissues. Similar changes were also seen in the serum levels of TNF-α and IL-6. However, the lower doses of 25 and 50mg/kg were more effective than 100mg/kg. Phosphorylated AMPKα (p-AMPK) in the myocardium was significantly elevated by 25mg/kg of metformin, slightly by 50mg/kg, but not by 100mg/kg. Chronic pre-treatment with metformin reduces post-myocardial infarction cardiac dysfunction and suppresses inflammatory responses, possibly through inhibition of TLR4 activities. This mechanism can be considered as a target to protect infarcted myocardium.

  7. Atorvastatin therapy during the peri-infarct period attenuates left ventricular dysfunction and remodeling after myocardial infarction.

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    Xian-Liang Tang

    Full Text Available Although statins impart a number of cardiovascular benefits, whether statin therapy during the peri-infarct period improves subsequent myocardial structure and function remains unclear. Thus, we evaluated the effects of atorvastatin on cardiac function, remodeling, fibrosis, and apoptosis after myocardial infarction (MI. Two groups of rats were subjected to permanent coronary occlusion. Group II (n = 14 received oral atorvastatin (10 mg/kg/d daily for 3 wk before and 4 wk after MI, while group I (n = 12 received equivalent doses of vehicle. Infarct size (Masson's trichrome-stained sections was similar in both groups. Compared with group I, echocardiographic left ventricular ejection fraction (LVEF and fractional area change (FAC were higher while LV end-diastolic volume (LVEDV and LV end-systolic and end-diastolic diameters (LVESD and LVEDD were lower in treated rats. Hemodynamically, atorvastatin-treated rats exhibited significantly higher dP/dt(max, end-systolic elastance (Ees, and preload recruitable stroke work (PRSW and lower LV end-diastolic pressure (LVEDP. Morphometrically, infarct wall thickness was greater in treated rats. The improvement of LV function by atorvastatin was associated with a decrease in hydroxyproline content and in the number of apoptotic cardiomyocyte nuclei. We conclude that atorvastatin therapy during the peri-infarct period significantly improves LV function and limits adverse LV remodeling following MI independent of a reduction in infarct size. These salubrious effects may be due in part to a decrease in myocardial fibrosis and apoptosis.

  8. Adenylyl cyclase 6 mediates loading-induced bone adaptation in vivo.

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    Lee, Kristen L; Hoey, David A; Spasic, Milos; Tang, Tong; Hammond, H Kirk; Jacobs, Christopher R

    2014-03-01

    Primary cilia are single, nonmotile, antenna-like structures extending from the apical membrane of most mammalian cells. They may mediate mechanotransduction, the conversion of external mechanical stimuli into biochemical intracellular signals. Previously we demonstrated that adenylyl cyclase 6 (AC6), a membrane-bound enzyme enriched in primary cilia of MLO-Y4 osteocyte-like cells, may play a role in a primary cilium-dependent mechanism of osteocyte mechanotransduction in vitro. In this study, we determined whether AC6 deletion impairs loading-induced bone formation in vivo. Skeletally mature mice with a global knockout of AC6 exhibited normal bone morphology and responded to osteogenic chemical stimuli similar to wild-type mice. Following ulnar loading over 3 consecutive days, bone formation parameters were assessed using dynamic histomorphometry. Mice lacking AC6 formed significantly less bone than control animals (41% lower bone formation rate). Furthermore, there was an attenuated flow-induced increase in COX-2 mRNA expression levels in primary bone cells isolated from AC6 knockout mice compared to controls (1.3±0.1- vs. 2.6±0.2-fold increase). Collectively, these data indicate that AC6 plays a role in loading-induced bone adaptation, and these findings are consistent with our previous studies implicating primary cilia and AC6 in a novel mechanism of osteocyte mechanotransduction. PMID:24277577

  9. Load-Induced Confinement Activates Diamond Lubrication by Water

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    Zilibotti, G.; Corni, S.; Righi, M. C.

    2013-10-01

    Tribochemical reactions are chemical processes, usually involving lubricant or environment molecules, activated at the interface between two solids in relative motion. They are difficult to be monitored in situ, which leaves a gap in the atomistic understanding required for their control. Here we report the real-time atomistic description of the tribochemical reactions occurring at the interface between two diamond films in relative motion, by means of large scale ab initio molecular dynamics. We show that the load-induced confinement is able to catalyze diamond passivation by water dissociative adsorption. Such passivation decreases the energy of the contacting surfaces and increases their electronic repulsion. At sufficiently high coverages, the latter prevents surface sealing, thus lowering friction. Our findings elucidate effects of the nanoscale confinement on reaction kinetics and surface thermodynamics, which are important for the design of new lubricants.

  10. High fat/low carbohydrate diet attenuates left ventricular hypertrophy and prevents myosin heavy chain isoform switching induced by chronic hypertenstion

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    A switch in the expression of myosin heavy chain isoform (MHC) alpha to beta is observed with left ventricular hypertrophy (LVH) and heart failure. This switch is associated with a defect in myocardial energy production and contractile dysfunction. Similar MHC isoform profile is observed in the fe...

  11. Numerical simulation of ice-load induced salt movements

    Science.gov (United States)

    Lang, Joerg; Al-Hseinat, Muayyad; Brandes, Christian; Hampel, Andrea; Hübscher, Christian; Winsemann, Jutta

    2015-04-01

    movement. The surface displacement due to ice-load induced salt movement will impact the pattern of glacigenic deformation, erosion and deposition. Ice-marginal uplift will provide favourable conditions for push-moraine formation, while subglacial subsidence of salt structures will enhance erosion and contribute to tunnel-valley incision. References Lang, J., Hampel, A., Brandes, C., Winsemann, J. (2014) Response of salt structures to ice-sheet loading: implications for ice-marginal and subglacial processes. Quaternary Science Reviews 101, 217-233. Liszkowski, J. (1993) The effects of Pleistocene ice-sheet loading-deloading cycles on the bedrock structure of Poland. Folia Quaternaria 64, 7-23.

  12. Turning Left

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    An increasing number of left-wing political figures are holding power in Latin America, raising eyebrows in Washington This is a banner election year in Latin America, with nine countries heading to the polls to select new leaders. But the succession of victories by left-leaning politicians, with more likely in the coming months, is expected to draw mounting concern from the United

  13. When the Left is left!

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    Asha J Mathew

    2014-09-01

    Full Text Available Persistent left superior vena cava is an uncommon vascular anomaly; however it is the most common anomaly of the thoracic venous system. It may be stand alone or associated with other congenital heart diseases and even other extracardiac anomalies. It is due to a lack of regression and adsorption of the left anterior cardinal vein. The persistence of this vessel renders a left subclavian approach for interventions on the right heart a challenge. It may be responsible for arrthymiias. We present a report of a persistent left superior vena cava draining into the coronary sinus with a coexisting normal right superior vena cava. Keeping in mind its widespread implications on cardiac procedures and a causative factor of cardiac disturbances we have considered its course, embryological source and clinical significance.

  14. Loading-Induced Heat-Shock Response in Bovine Intervertebral Disc Organ Culture.

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    Chooi, Wai Hon; Chan, Samantha Chun Wai; Gantenbein, Benjamin; Chan, Barbara Pui

    2016-01-01

    Mechanical loading has been shown to affect cell viability and matrix maintenance in the intervertebral disc (IVD) but there is no investigation on how cells survive mechanical stress and whether the IVD cells perceive mechanical loading as stress and respond by expression of heat shock proteins. This study investigates the stress response in the IVD in response to compressive loading. Bovine caudal disc organ culture was used to study the effect of physiological range static loading and dynamic loading. Cell activity, gene expression and immunofluorescence staining were used to analyze the cell response. Cell activity and cytoskeleton of the cells did not change significantly after loading. In gene expression analysis, significant up-regulation of heat shock protein-70 (HSP70) was observed in nucleus pulposus after two hours of loading. However, the expression of the matrix remodeling genes did not change significantly after loading. Similarly, expressions of stress response and matrix remodeling genes changed with application and removal of the dynamic loading. The results suggest that stress response was induced by physiological range loading without significantly changing cell activity and upregulating matrix remodeling. This study provides direct evidence on loading induced stress response in IVD cells and contributes to our understanding in the mechanoregulation of intervertebral disc cells. PMID:27580124

  15. Load-induced debonding of FRP composites applied to reinforced concrete

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    Blok, Joel; Brown, Jeff

    2009-05-01

    Fiber-reinforced polymer (FRP) composites are widely used to increase the flexural and shear capacity of reinforced concrete (RC) elements. One potential disadvantage is that strengthened surfaces are no longer visible and cracks or delaminations that result from excessive loading or fatigue may go undetected. This research investigated thermal imaging techniques for monitoring and evaluating load-induced delamination of FRP composites applied to small scale RC beams. Two beams (3.5 in x 4.5 in x 58 in) were loaded monotonically to failure. Infrared thermography (IRT) inspections were performed at various load levels through failure using a composite phase imaging technique. Two similar beams were tested in fatigue and periodic IRT inspections were performed at 50,000-cycle intervals. Individual phase values for each pixel were designated as "well-bonded", "suspect" or "unbonded" to indicate the quality of FRP bond. Suspect areas included regions of excess thickened-epoxy tack-coat and smaller installation defects in the unloaded specimens. The long-term objective of this research is to develop a practical framework for conducting quantitative IRT inspections of FRP composites applied to RC and incorporating these results into acceptance criteria for new installations and predictions for the remaining service life of in-service FRP systems. This method may also offer insight into the necessity for repairs to in-service systems.

  16. Left heart catheterization

    Science.gov (United States)

    Catheterization - left heart ... then moved through the aortic valve into the left side of your heart. The pressure is measured ... coronary angiography) Take x-ray pictures of the left side of the heart (ventriculography)

  17. Hypoplastic left heart syndrome

    Science.gov (United States)

    HLHS; Congenital heart - hypoplastic left heart; Cyanotic heart disease - hypoplastic left heart ... Hypoplastic left heart is a rare type of congenital heart disease. It is more common in males than in ...

  18. Capsaicin mimics mechanical load-induced intracellular signaling events: involvement of TRPV1-mediated calcium signaling in induction of skeletal muscle hypertrophy.

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    Ito, Naoki; Ruegg, Urs T; Kudo, Akira; Miyagoe-Suzuki, Yuko; Takeda, Shin'ichi

    2013-01-01

    Mechanical load-induced intracellular signaling events are important for subsequent skeletal muscle hypertrophy. We previously showed that load-induced activation of the cation channel TRPV1 caused an increase in intracellular calcium concentrations ([Ca ( 2+) ]i) and that this activated mammalian target of rapamycin (mTOR) and promoted muscle hypertrophy. However, the link between mechanical load-induced intracellular signaling events, and the TRPV1-mediated increases in [Ca ( 2+) ]i are not fully understood. Here we show that administration of the TRPV1 agonist, capsaicin, induces phosphorylation of mTOR, p70S6K, S6, Erk1/2 and p38 MAPK, but not Akt, AMPK or GSK3β. Furthermore, the TRPV1-induced phosphorylation patterns resembled those induced by mechanical load. Our results continue to highlight the importance of TRPV1-mediated calcium signaling in load-induced intracellular signaling pathways.

  19. Heat shock transcription factor 1-deficiency attenuates overloading-associated hypertrophy of mouse soleus muscle.

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    Tomoyuki Koya

    Full Text Available Hypertrophic stimuli, such as mechanical stress and overloading, induce stress response, which is mediated by heat shock transcription factor 1 (HSF1, and up-regulate heat shock proteins (HSPs in mammalian skeletal muscles. Therefore, HSF1-associated stress response may play a key role in loading-associated skeletal muscle hypertrophy. The purpose of this study was to investigate the effects of HSF1-deficiency on skeletal muscle hypertrophy caused by overloading. Functional overloading on the left soleus was performed by cutting the distal tendons of gastrocnemius and plantaris muscles for 4 weeks. The right muscle served as the control. Soleus muscles from both hindlimbs were dissected 2 and 4 weeks after the operation. Hypertrophy of soleus muscle in HSF1-null mice was partially inhibited, compared with that in wild-type (C57BL/6J mice. Absence of HSF1 partially attenuated the increase of muscle wet weight and fiber cross-sectional area of overloaded soleus muscle. Population of Pax7-positive muscle satellite cells in HSF1-null mice was significantly less than that in wild-type mice following 2 weeks of overloading (p<0.05. Significant up-regulations of interleukin (IL-1β and tumor necrosis factor mRNAs were observed in HSF1-null, but not in wild-type, mice following 2 weeks of overloading. Overloading-related increases of IL-6 and AFT3 mRNA expressions seen after 2 weeks of overloading tended to decrease after 4 weeks in both types of mice. In HSF1-null mice, however, the significant overloading-related increase in the expression of IL-6, not ATF3, mRNA was noted even at 4th week. Inhibition of muscle hypertrophy might be attributed to the greater and prolonged enhancement of IL-6 expression. HSF1 and/or HSF1-mediated stress response may, in part, play a key role in loading-induced skeletal muscle hypertrophy.

  20. Physical weight loading induces expression of tryptophan hydroxylase 2 in the brain stem.

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    Joon W Shim

    Full Text Available Sustaining brain serotonin is essential in mental health. Physical activities can attenuate mental problems by enhancing serotonin signaling. However, such activity is not always possible in disabled individuals or patients with dementia. Knee loading, a form of physical activity, has been found to mimic effects of voluntary exercise. Focusing on serotonergic signaling, we addressed a question: Does local mechanical loading to the skeleton elevate expression of tryptophan hydroxylase 2 (tph2 that is a rate-limiting enzyme for brain serotonin? A 5 min knee loading was applied to mice using 1 N force at 5 Hz for 1,500 cycles. A 5-min treadmill running was used as an exercise (positive control, and a 90-min tail suspension was used as a stress (negative control. Expression of tph2 was determined 30 min - 2 h in three brain regions --frontal cortex (FC, ventromedial hypothalamus (VMH, and brain stem (BS. We demonstrated for the first time that knee loading and treadmill exercise upregulated the mRNA level of tph2 in the BS, while tail suspension downregulated it. The protein level of tph2 in the BS was also upregulated by knee loading and downregulated by tail suspension. Furthermore, the downregulation of tph2 mRNA by tail suspension can be partially suppressed by pre-application of knee loading. The expression of tph2 in the FC and VMH was not significantly altered with knee loading. In this study we provided evidence that peripheral mechanical loading can activate central tph2 expression, suggesting that physical cues may mediate tph2-cathalyzed serotonergic signaling in the brain.

  1. Uncommon breast tumor attenuation artifact on radionuclide ventriculography.

    Science.gov (United States)

    Metrard, Gilles; Girault, Sylvie; Capitain, Olivier; Jeanguillaume, Christian; Rakotonirina, Hervé; Berthelot, Cécile; Le Jeune, Jean-Jacques; Morel, Olivier

    2008-04-01

    A 39-year-old woman with locally advanced left breast cancer (T4 N0 M0) underwent equilibrium radionuclide ventriculography for baseline assessment of left ventricular function before neoadjuvant chemotherapy. The left ventricular ejection fraction was 76% at 75 beats per minute, without localized wall motion abnormality. In the best septal left anterior oblique projection, a large photopenic "halo" surrounded the cardiac chambers, mimicking a pericardial effusion. In fact, this aspect resulted from an attenuation artifact by a large left breast tumor, as demonstrated by FDG-PET/CT imaging. PMID:18356673

  2. Stormwater Attenuation by Green Roofs

    Science.gov (United States)

    Sims, A.; O'Carroll, D. M.; Robinson, C. E.; Smart, C. C.

    2014-12-01

    Innovative municipal stormwater management technologies are urgently required in urban centers. Inadequate stormwater management can lead to excessive flooding, channel erosion, decreased stream baseflows, and degraded water quality. A major source of urban stormwater is unused roof space. Green roofs can be used as a stormwater management tool to reduce roof generated stormwater and generally improve the quality of runoff. With recent legislation in some North American cities, including Toronto, requiring the installation of green roofs on large buildings, research on the effectiveness of green roofs for stormwater management is important. This study aims to assess the hydrologic response of an extensive sedum green roof in London, Ontario, with emphasis on the response to large precipitation events that stress municipal stormwater infrastructure. A green roof rapidly reaches field capacity during large storm events and can show significantly different behavior before and after field capacity. At field capacity a green roof has no capillary storage left for retention of stormwater, but may still be an effective tool to attenuate peak runoff rates by transport through the green roof substrate. The attenuation of green roofs after field capacity is linked to gravity storage, where gravity storage is the water that is temporarily stored and can drain freely over time after field capacity has been established. Stormwater attenuation of a modular experimental green roof is determined from water balance calculations at 1-minute intervals. Data is used to evaluate green roof attenuation and the impact of field capacity on peak flow rates and gravity storage. In addition, a numerical model is used to simulate event based stormwater attenuation. This model is based off of the Richards equation and supporting theory of multiphase flow through porous media.

  3. 高速破片在防雷舱结构中引起的冲击荷载的理论研究%Shock loading induced by high speed fragment in cabin near shipboard

    Institute of Scientific and Technical Information of China (English)

    唐廷; 朱锡; 侯海量; 陈长海

    2013-01-01

    Applying the one dimension plane wave theory, the shock loading induced by high speed large fragment in cabin near shipboard was studied. A theretical formula of initial shock loading was attained and proved by comparing with the result of FEM. The influences of parameters of fragment on shock loading was analyzed based on the theoretical formula. The results show that the velocity of fragment is in direct ratio with the peak value of shock loading. The more rapidly fragment moves, the bigger the peak value. And the velocity of fragment has no influence upon decay of shock loading, namely, the shock loading of fragment with different velocity will decay according to a same mode. The shock loading induced by fragment with different thickness results in a same peak value, but different duration. The thicker the fragment, the longer the duration. Based on the theoretical analysis, the functional form of geometrical attenuation was established. By the regression analysis on the data of numerical test, the coefficient of geometrical attenuation of shock wave was got.%运用一维平面波理论,研究大型高速破片在防雷舱结构中引起的冲击荷载,得到了初始冲击荷载的理论公式.与有限元计算结果进行比较,证明了理论公式的正确性.运用理论计算公式分析了破片参数对冲击荷载的影响,结果表明:破片速度与冲击荷载峰值成正比,速度越快,峰值越大;速度越慢,峰值越小.而破片速度对冲击荷载的衰减没有影响,即不同速度的破片在水中引起的冲击荷载具有相同的衰减规律.不同厚度破片引起的冲击荷载的具有相同的峰值,但有不同的作用时间.破片的越厚,荷载作用时间越长;破片越薄,荷载作用时间越短.最后基于理论分析确定了几何衰减的函数形式,采用数值试验数据进行回归分析,得到了冲击波的几何衰减系数.

  4. Left atrial volume index

    DEFF Research Database (Denmark)

    Poulsen, Mikael K; Dahl, Jordi S; Henriksen, Jan Erik;

    2013-01-01

    To determine the prognostic importance of left atrial (LA) dilatation in patients with type 2 diabetes (T2DM) and no history of cardiovascular disease.......To determine the prognostic importance of left atrial (LA) dilatation in patients with type 2 diabetes (T2DM) and no history of cardiovascular disease....

  5. Photonic Crystal Fiber Attenuator

    Institute of Scientific and Technical Information of China (English)

    Joo Beom Eom; Hokyung Kim; Jinchae Kim; Un-Chul Paek; Byeong Ha Lee

    2003-01-01

    We propose a novel fiber attenuator based on photonic crystal fibers. The difference in the modal field diameters of a conventional single mode fiber and a photonic crystal fiber was used. A variable optical attenuator was also achieved by applying macro-bending on the PCF part of the proposed attenuator

  6. Left-Handed Connections.

    Science.gov (United States)

    Lipson, Alice M.

    1984-01-01

    The following aspects of left-handedness are discussed: etiology and associated learning and developmental disorders; right-brain dominance and how to detect it; adaptations to the physical learning environment; behavior patterns; and teaching techniques. (JW)

  7. Variable laser attenuator

    Science.gov (United States)

    Foltyn, Stephen R.

    1988-01-01

    The disclosure relates to low loss, high power variable attenuators comprng one or more transmissive and/or reflective multilayer dielectric filters. The attenuator is particularly suitable to use with unpolarized lasers such as excimer lasers. Beam attenuation is a function of beam polarization and the angle of incidence between the beam and the filter and is controlled by adjusting the angle of incidence the beam makes to the filter or filters. Filters are selected in accordance with beam wavelength.

  8. Hypoplastic left heart syndrome (image)

    Science.gov (United States)

    Hypoplastic left heart syndrome is a congenital heart condition that occurs during the development of the heart in the ... womb. During the heart's development, parts of the left side of the heart (mitral valve, left ventricle ...

  9. Artificial Left Ventricle

    CERN Document Server

    Ranjbar, Saeed; Meybodi, Mahmood Emami

    2014-01-01

    This Artificial left ventricle is based on a simple conic assumption shape for left ventricle where its motion is made by attached compressed elastic tubes to its walls which are regarded to electrical points at each nodal .This compressed tubes are playing the role of myofibers in the myocardium of the left ventricle. These elastic tubes have helical shapes and are transacting on these helical bands dynamically. At this invention we give an algorithm of this artificial left ventricle construction that of course the effect of the blood flow in LV is observed with making beneficiary used of sensors to obtain this effecting, something like to lifegates problem. The main problem is to evaluate powers that are interacted between elastic body (left ventricle) and fluid (blood). The main goal of this invention is to show that artificial heart is not just a pump, but mechanical modeling of LV wall and its interaction with blood in it (blood movement modeling) can introduce an artificial heart closed to natural heart...

  10. Systemic mesenchymal stem cell administration enhances bone formation in fracture repair but not load-induced bone formation

    Directory of Open Access Journals (Sweden)

    AE Rapp

    2015-01-01

    Full Text Available Mesenchymal stem cells (MSC were shown to support bone regeneration, when they were locally transplanted into poorly healing fractures. The benefit of systemic MSC transplantation is currently less evident. There is consensus that systemically applied MSC are recruited to the site of injury, but it is debated whether they actually support bone formation. Furthermore, the question arises as to whether circulating MSC are recruited only in case of injury or whether they also participate in mechanically induced bone formation. To answer these questions we injected green fluorescent protein (GFP-labelled MSC into C57BL/6J mice, which were subjected either to a femur osteotomy or to non-invasive mechanical ulna loading to induce bone formation. We detected GFP-labelled MSC in the early (day 10 and late fracture callus (day 21 by immunohistochemistry. Stromal cell-derived factor 1 (SDF-1 or CXCL-12, a key chemokine for stem cell attraction, was strongly expressed by virtually all cells near the osteotomy – indicating that SDF-1 may mediate cell migration to the site of injury. We found no differences in SDF-1 expression between the groups. Micro-computed tomography (µCT revealed significantly more bone in the callus of the MSC treated mice compared to untreated controls. The bending stiffness of callus was not significantly altered after MSC-application. In contrast, we failed to detect GFP-labelled MSC in the ulna after non-invasive mechanical loading. Histomorphometry and µCT revealed a significant load-induced increase in bone formation; however, no further increase was found after MSC administration. Concluding, our results suggest that systemically administered MSC are recruited and support bone formation only in case of injury but not in mechanically induced bone formation.

  11. The Postmodern Left

    Directory of Open Access Journals (Sweden)

    Niall Lucy

    2011-04-01

    Full Text Available A certain version of the political left is at one with conservatives in misrepresenting ‘postmodernism’ in order to denounce it. For this ‘left’, which recoils from the left’s historically indivisible association with Marx, the purpose of politics is simply to win government for itself. Our argument here is that, ironically, such a purpose mirrors the very lack of purpose that conservatives define ‘postmodernism’ to represent. Hence the recent call by Clive Hamilton for the left to turn to the churches for moral guidance, in the absence of any meaningful political convictions.

  12. PERSISTENT LEFT SUPERIOR VENACAVA

    Directory of Open Access Journals (Sweden)

    Devinder Singh

    2014-05-01

    Full Text Available A Persistent Left Superior Venacava (PLSVC is the most common variation of the thoracic venous system and rare congenital vascular anomaly and is prevalent in 0.3% of the population. It may be associated with other cardiovascular abnormalities including atrial septal defect, bicuspid aortic valve, coarctation of aorta, coronary sinus ostial atresia, and cor triatriatum. Incidental rotation of a dilated coronary sinus on echocardiography should raise the suspicion of PLSVC. The diagnosis should be confirmed by saline contrast echocardiography. Condition is usually asymptomatic. Here we present a rare case of persistent left superior vena cava presented in OPD with dyspnoea & palpitations.

  13. Left atrial appendage occlusion

    Directory of Open Access Journals (Sweden)

    Ahmad Mirdamadi

    2013-01-01

    Full Text Available Left atrial appendage (LAA occlusion is a treatment strategy to prevent blood clot formation in atrial appendage. Although, LAA occlusion usually was done by catheter-based techniques, especially percutaneous trans-luminal mitral commissurotomy (PTMC, it can be done during closed and open mitral valve commissurotomy (CMVC, OMVC and mitral valve replacement (MVR too. Nowadays, PTMC is performed as an optimal management of severe mitral stenosis (MS and many patients currently are treated by PTMC instead of previous surgical methods. One of the most important contraindications of PTMC is presence of clot in LAA. So, each patient who suffers of severe MS is evaluated by Trans-Esophageal Echocardiogram to rule out thrombus in LAA before PTMC. At open heart surgery, replacement of the mitral valve was performed for 49-year-old woman. Also, left atrial appendage occlusion was done during surgery. Immediately after surgery, echocardiography demonstrates an echo imitated the presence of a thrombus in left atrial appendage area, although there was not any evidence of thrombus in pre-pump TEE. We can conclude from this case report that when we suspect of thrombus of left atrial, we should obtain exact history of previous surgery of mitral valve to avoid misdiagnosis clotted LAA, instead of obliterated LAA. Consequently, it can prevent additional evaluations and treatments such as oral anticoagulation and exclusion or postponing surgeries including PTMC.

  14. No Cow Left Behind

    Science.gov (United States)

    Remsen, Kenneth A.

    2004-01-01

    As a principal facing the task of figuring out all the complexities of the No Child Left Behind legislation, Kenneth Remsen, has concluded there is a strong belief that testing students is the answer to bringing about improvements in student performance. Because testing seems to be a cornerstone to improving performance, he doesn't understand why…

  15. Left or Right

    Institute of Scientific and Technical Information of China (English)

    常厚飞

    2007-01-01

    In Europe people hold the fork in the left hand and the knife in the right throughout the meal, a system that is generally agreed to be more efficient than the American zigzag method. Americans hold both the fork and the knife in their right hands throughout the meal,

  16. Left-handed completeness

    OpenAIRE

    Kozen, Dexter; Silva, Alexandra

    2012-01-01

    Lecture Notes in Computer Science 7560, 2012 We give a new, significantly shorter proof of the completeness of the left-handed star rule of Kleene algebra. The proof exposes the rich interaction of algebra and coalgebra in the theory of Kleene algebra.

  17. Attenuation correction for the NIH ATLAS small animal PET scanner

    CERN Document Server

    Yao, Rutao; Liow, JeihSan; Seidel, Jurgen

    2003-01-01

    We evaluated two methods of attenuation correction for the NIH ATLAS small animal PET scanner: 1) a CT-based method that derives 511 keV attenuation coefficients (mu) by extrapolation from spatially registered CT images; and 2) an analytic method based on the body outline of emission images and an empirical mu. A specially fabricated attenuation calibration phantom with cylindrical inserts that mimic different body tissues was used to derive the relationship to convert CT values to (I for PET. The methods were applied to three test data sets: 1) a uniform cylinder phantom, 2) the attenuation calibration phantom, and 3) a mouse injected with left bracket **1**8F right bracket FDG. The CT-based attenuation correction factors were larger in non-uniform regions of the imaging subject, e.g. mouse head, than the analytic method. The two methods had similar correction factors for regions with uniform density and detectable emission source distributions.

  18. Hypoplastic left heart syndrome

    Directory of Open Access Journals (Sweden)

    Thiagarajan Ravi

    2007-05-01

    Full Text Available Abstract Hypoplastic left heart syndrome(HLHS refers to the abnormal development of the left-sided cardiac structures, resulting in obstruction to blood flow from the left ventricular outflow tract. In addition, the syndrome includes underdevelopment of the left ventricle, aorta, and aortic arch, as well as mitral atresia or stenosis. HLHS has been reported to occur in approximately 0.016 to 0.036% of all live births. Newborn infants with the condition generally are born at full term and initially appear healthy. As the arterial duct closes, the systemic perfusion becomes decreased, resulting in hypoxemia, acidosis, and shock. Usually, no heart murmur, or a non-specific heart murmur, may be detected. The second heart sound is loud and single because of aortic atresia. Often the liver is enlarged secondary to congestive heart failure. The embryologic cause of the disease, as in the case of most congenital cardiac defects, is not fully known. The most useful diagnostic modality is the echocardiogram. The syndrome can be diagnosed by fetal echocardiography between 18 and 22 weeks of gestation. Differential diagnosis includes other left-sided obstructive lesions where the systemic circulation is dependent on ductal flow (critical aortic stenosis, coarctation of the aorta, interrupted aortic arch. Children with the syndrome require surgery as neonates, as they have duct-dependent systemic circulation. Currently, there are two major modalities, primary cardiac transplantation or a series of staged functionally univentricular palliations. The treatment chosen is dependent on the preference of the institution, its experience, and also preference. Although survival following initial surgical intervention has improved significantly over the last 20 years, significant mortality and morbidity are present for both surgical strategies. As a result pediatric cardiologists continue to be challenged by discussions with families regarding initial decision

  19. Landing gear noise attenuation

    Science.gov (United States)

    Moe, Jeffrey W. (Inventor); Whitmire, Julia (Inventor); Kwan, Hwa-Wan (Inventor); Abeysinghe, Amal (Inventor)

    2011-01-01

    A landing gear noise attenuator mitigates noise generated by airframe deployable landing gear. The noise attenuator can have a first position when the landing gear is in its deployed or down position, and a second position when the landing gear is in its up or stowed position. The noise attenuator may be an inflatable fairing that does not compromise limited space constraints associated with landing gear retraction and stowage. A truck fairing mounted under a truck beam can have a compliant edge to allow for non-destructive impingement of a deflected fire during certain conditions.

  20. Neutrosophic Left Almost Semigroup

    Directory of Open Access Journals (Sweden)

    Mumtaz Ali

    2014-06-01

    Full Text Available In this paper we extend the theory of neutrosophy to study left almost semigroup shortly LAsemigroup. We generalize the concepts of LA-semigroup to form that for neutrosophic LA-semigroup. We also extend the ideal theory of LA-semigroup to neutrosophy and discuss different kinds of neutrosophic ideals. We also find some new type of neutrosophic ideal which is related to the strong or pure part of neutrosophy. We have given many examples to illustrate the theory of neutrosophic LA-semigroup and display many properties of neutrosophic LA-semigroup in this paper.

  1. Inhibition of T-Type Voltage Sensitive Calcium Channel Reduces Load-Induced OA in Mice and Suppresses the Catabolic Effect of Bone Mechanical Stress on Chondrocytes

    OpenAIRE

    Srinivasan, Padma P.; Parajuli, Ashutosh; Price, Christopher; Wang, Liyun; Duncan, Randall L.; Kirn-Safran, Catherine B.

    2015-01-01

    Voltage-sensitive calcium channels (VSCC) regulate cellular calcium influx, one of the earliest responses to mechanical stimulation in osteoblasts. Here, we postulate that T-type VSCCs play an essential role in bone mechanical response to load and participate in events leading to the pathology of load-induced OA. Repetitive mechanical insult was used to induce OA in Cav3.2 T-VSCC null and wild-type control mouse knees. Osteoblasts (MC3T3-E1) and chondrocytes were treated with a selective T-VS...

  2. Planetary Ices Attenuation Properties

    Science.gov (United States)

    McCarthy, Christine; Castillo-Rogez, Julie C.

    In this chapter, we review the topic of energy dissipation in the context of icy satellites experiencing tidal forcing. We describe the physics of mechanical dissipation, also known as attenuation, in polycrystalline ice and discuss the history of laboratory methods used to measure and understand it. Because many factors - such as microstructure, composition and defect state - can influence rheological behavior, we review what is known about the mechanisms responsible for attenuation in ice and what can be inferred from the properties of rocks, metals and ceramics. Since attenuation measured in the laboratory must be carefully scaled to geologic time and to planetary conditions in order to provide realistic extrapolation, we discuss various mechanical models that have been used, with varying degrees of success, to describe attenuation as a function of forcing frequency and temperature. We review the literature in which these models have been used to describe dissipation in the moons of Jupiter and Saturn. Finally, we address gaps in our present knowledge of planetary ice attenuation and provide suggestions for future inquiry.

  3. Frequency Dependent Attenuation Revisited

    CERN Document Server

    Richard, Kowar; Xavier, Bonnefond

    2009-01-01

    The work is inspired by thermo-and photoacoustic imaging, where recent efforts are devoted to take into account attenuation and varying wave speed parameters. In this paper we study causal equations describing propagation of attenuated pressure waves. We review standard models like frequency power laws and and the thermo-viscous equation. The lack of causality of standard models in the parameter range relevant for photoacoustic imaging requires to derive novel equations. The main ingredients for deriving causal equations are the Kramers-Kronig relation and the mathematical concept of linear system theory. The theoretical results of this work are underpined by numerical experiments.

  4. Left Artinian Algebraic Algebras

    Institute of Scientific and Technical Information of China (English)

    S. Akbari; M. Arian-Nejad

    2001-01-01

    Let R be a left artinian central F-algebra, T(R) = J(R) + [R, R],and U(R) the group of units of R. As one of our results, we show that, if R is algebraic and char F = 0, then the number of simple components of -R = R/J(R)is greater than or equal to dimF R/T(R). We show that, when char F = 0 or F is uncountable, R is algebraic over F if and only if [R, R] is algebraic over F. As another approach, we prove that R is algebraic over F if and only if the derived subgroup of U(R) is algebraic over F. Also, we present an elementary proof for a special case of an old question due to Jacobson.

  5. [Left-handedness and health].

    Science.gov (United States)

    Milenković, Sanja; Belojević, Goran; Kocijancić, Radojka

    2010-01-01

    Hand dominance is defined as a proneness to use one hand rather than another in performing the majority of activities and this is the most obvious example of cerebral lateralization and an exclusive human characteristic. Left-handed people comprise 6-14% of the total population, while in Serbia, this percentage is 5-10%, moving from undeveloped to developed environments, where a socio-cultural pressure is less present. There is no agreement between investigators who in fact may be considered a left-handed person, about the percentage of left-handers in the population and about the etiology of left-handedness. In the scientific literature left-handedness has been related to health disorders (spine deformities, immunological disorders, migraine, neurosis, depressive psychosis, schizophrenia, insomnia, homosexuality, diabetes mellitus, arterial hypertension, sleep apnea, enuresis nocturna and Down Syndrome), developmental disorders (autism, dislexia and sttutering) and traumatism. The most reliable scientific evidences have been published about the relationship between left-handedness and spinal deformities in school children in puberty and with traumatism in general population. The controversy of other results in up-to-now investigations of health aspects of left-handedness may partly be explained by a scientific disagreement whether writing with the left hand is a sufficient criterium for left-handedness, or is it necessary to investigate other parameters for laterality assessment. Explanation of health aspects of left-handedness is dominantly based on Geschwind-Galaburda model about "anomalous" cerebral domination, as a consequence of hormonal disbalance.

  6. Maintenance of muscle mass and load-induced growth in Muscle RING Finger 1 null mice with age.

    Science.gov (United States)

    Hwee, Darren T; Baehr, Leslie M; Philp, Andrew; Baar, Keith; Bodine, Sue C

    2014-02-01

    Age-related loss of muscle mass occurs to varying degrees in all individuals and has a detrimental effect on morbidity and mortality. Muscle RING Finger 1 (MuRF1), a muscle-specific E3 ubiquitin ligase, is believed to mediate muscle atrophy through the ubiquitin proteasome system (UPS). Deletion of MuRF1 (KO) in mice attenuates the loss of muscle mass following denervation, disuse, and glucocorticoid treatment; however, its role in age-related muscle loss is unknown. In this study, skeletal muscle from male wild-type (WT) and MuRF1 KO mice was studied up to the age of 24 months. Muscle mass and fiber cross-sectional area decreased significantly with age in WT, but not in KO mice. In aged WT muscle, significant decreases in proteasome activities, especially 20S and 26S β5 (20-40% decrease), were measured and were associated with significant increases in the maladaptive endoplasmic reticulum (ER) stress marker, CHOP. Conversely, in aged MuRF1 KO mice, 20S or 26S β5 proteasome activity was maintained or decreased to a lesser extent than in WT mice, and no increase in CHOP expression was measured. Examination of the growth response of older (18 months) mice to functional overload revealed that old WT mice had significantly less growth relative to young mice (1.37- vs. 1.83-fold), whereas old MuRF1 KO mice had a normal growth response (1.74- vs. 1.90-fold). These data collectively suggest that with age, MuRF1 plays an important role in the control of skeletal muscle mass and growth capacity through the regulation of cellular stress.

  7. Principally Left Hereditary and Principally Left Strong Radicals

    Institute of Scientific and Technical Information of China (English)

    S. Tumurbat; R. Wiegandt

    2001-01-01

    A radical γ is normal if and only if γ is principally left hereditary and principally left strong (i.e., γ(L) = L e A and Lz ∈γ for all z ∈ L imply L γ(A)). Let a radical γ satisfy that A°∈γ and S° A° imply S°∈γ.Then γ is a hereditary normal radical if and only if γ is principally left strong and γ {A | (A, +,◇a) ∈γ a ∈ A}, where the multiplication ◇a is defined by x ◇a y = xay. The Behrens radical class B is the largest principally left hereditary subclass of the Brown-McCoy radical class G. Neither3 nor G is principally left strong.

  8. Inhibition of T-Type Voltage Sensitive Calcium Channel Reduces Load-Induced OA in Mice and Suppresses the Catabolic Effect of Bone Mechanical Stress on Chondrocytes.

    Directory of Open Access Journals (Sweden)

    Padma P Srinivasan

    Full Text Available Voltage-sensitive calcium channels (VSCC regulate cellular calcium influx, one of the earliest responses to mechanical stimulation in osteoblasts. Here, we postulate that T-type VSCCs play an essential role in bone mechanical response to load and participate in events leading to the pathology of load-induced OA. Repetitive mechanical insult was used to induce OA in Cav3.2 T-VSCC null and wild-type control mouse knees. Osteoblasts (MC3T3-E1 and chondrocytes were treated with a selective T-VSCC inhibitor and subjected to fluid shear stress to determine how blocking of T-VSCCs alters the expression profile of each cell type upon mechanical stimulation. Conditioned-media (CM obtained from static and sheared MC3T3-E1 was used to assess the effect of osteoblast-derived factors on the chondrocyte phenotype. T-VSCC null knees exhibited significantly lower focal articular cartilage damage than age-matched controls. In vitro inhibition of T-VSCC significantly reduced the expression of both early and late mechanoresponsive genes in osteoblasts but had no effect on gene expression in chondrocytes. Furthermore, treatment of chondrocytes with CM obtained from sheared osteoblasts induced expression of markers of hypertrophy in chondrocytes and this was nearly abolished when osteoblasts were pre-treated with the T-VSCC-specific inhibitor. These results indicate that T-VSCC plays a role in signaling events associated with induction of OA and is essential to the release of osteoblast-derived factors that promote an early OA phenotype in chondrocytes. Further, these findings suggest that local inhibition of T-VSCC may serve as a therapy for blocking load-induced bone formation that results in cartilage degeneration.

  9. Control algorithms for dynamic attenuators

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, Scott S., E-mail: sshsieh@stanford.edu [Department of Radiology, Stanford University, Stanford, California 94305 and Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States); Pelc, Norbert J. [Department of Radiology, Stanford University, Stanford California 94305 and Department of Bioengineering, Stanford University, Stanford, California 94305 (United States)

    2014-06-15

    Purpose: The authors describe algorithms to control dynamic attenuators in CT and compare their performance using simulated scans. Dynamic attenuators are prepatient beam shaping filters that modulate the distribution of x-ray fluence incident on the patient on a view-by-view basis. These attenuators can reduce dose while improving key image quality metrics such as peak or mean variance. In each view, the attenuator presents several degrees of freedom which may be individually adjusted. The total number of degrees of freedom across all views is very large, making many optimization techniques impractical. The authors develop a theory for optimally controlling these attenuators. Special attention is paid to a theoretically perfect attenuator which controls the fluence for each ray individually, but the authors also investigate and compare three other, practical attenuator designs which have been previously proposed: the piecewise-linear attenuator, the translating attenuator, and the double wedge attenuator. Methods: The authors pose and solve the optimization problems of minimizing the mean and peak variance subject to a fixed dose limit. For a perfect attenuator and mean variance minimization, this problem can be solved in simple, closed form. For other attenuator designs, the problem can be decomposed into separate problems for each view to greatly reduce the computational complexity. Peak variance minimization can be approximately solved using iterated, weighted mean variance (WMV) minimization. Also, the authors develop heuristics for the perfect and piecewise-linear attenuators which do not requirea priori knowledge of the patient anatomy. The authors compare these control algorithms on different types of dynamic attenuators using simulated raw data from forward projected DICOM files of a thorax and an abdomen. Results: The translating and double wedge attenuators reduce dose by an average of 30% relative to current techniques (bowtie filter with tube current

  10. Two Lefts in Latin America?

    DEFF Research Database (Denmark)

    Christensen, Steen Fryba

    In this working paper I list five researchers' categorizations of the Latin American left in power (april 2006) in a schematic form. The most important criteria for the categorizations are given.......In this working paper I list five researchers' categorizations of the Latin American left in power (april 2006) in a schematic form. The most important criteria for the categorizations are given....

  11. The Left-Handed Writer.

    Science.gov (United States)

    Bloodsworth, James Gaston

    Contrary to the beliefs of many, right-handedness is not a single factor existing in almost all people, with a few exceptions termed left-handed: neither extreme exists independently of the other. During the first 4 years of life there is a period of fluctuation between right and left-handed dominance. Statistics and findings vary in determining…

  12. [Left-handedness and health].

    Science.gov (United States)

    Milenković, Sanja; Belojević, Goran; Kocijancić, Radojka

    2010-01-01

    Hand dominance is defined as a proneness to use one hand rather than another in performing the majority of activities and this is the most obvious example of cerebral lateralization and an exclusive human characteristic. Left-handed people comprise 6-14% of the total population, while in Serbia, this percentage is 5-10%, moving from undeveloped to developed environments, where a socio-cultural pressure is less present. There is no agreement between investigators who in fact may be considered a left-handed person, about the percentage of left-handers in the population and about the etiology of left-handedness. In the scientific literature left-handedness has been related to health disorders (spine deformities, immunological disorders, migraine, neurosis, depressive psychosis, schizophrenia, insomnia, homosexuality, diabetes mellitus, arterial hypertension, sleep apnea, enuresis nocturna and Down Syndrome), developmental disorders (autism, dislexia and sttutering) and traumatism. The most reliable scientific evidences have been published about the relationship between left-handedness and spinal deformities in school children in puberty and with traumatism in general population. The controversy of other results in up-to-now investigations of health aspects of left-handedness may partly be explained by a scientific disagreement whether writing with the left hand is a sufficient criterium for left-handedness, or is it necessary to investigate other parameters for laterality assessment. Explanation of health aspects of left-handedness is dominantly based on Geschwind-Galaburda model about "anomalous" cerebral domination, as a consequence of hormonal disbalance. PMID:20607990

  13. Left-handedness and health

    Directory of Open Access Journals (Sweden)

    Milenković Sanja

    2010-01-01

    Full Text Available Hand dominance is defined as a proneness to use one hand rather than another in performing the majority of activities and this is the most obvious example of cerebral lateralization and an exclusive human characteristic. Left-handed people comprise 6-14% of the total population, while in Serbia, this percentage is 5-10%, moving from undeveloped to developed environments, where a socio-cultural pressure is less present. There is no agreement between investigators who in fact may be considered a left-handed person, about the percentage of left-handers in the population and about the etiology of left-handedness. In the scientific literature left-handedness has been related to health disorders (spine deformities, immunological disorders, migraine, neurosis, depressive psychosis, schizophrenia, insomnia, homosexuality, diabetes mellitus, arterial hypertension, sleep apnea, enuresis nocturna and Down Syndrome, developmental disorders (autism, dislexia and sttutering and traumatism. The most reliable scientific evidences have been published about the relationship between left-handedness and spinal deformities in school children in puberty and with traumatism in general population. The controversy of other results in up-to-now investigations of health aspects of left-handedness may partly be explained by a scientific disagreement whether writing with the left hand is a sufficient criterium for left-handedness, or is it necessary to investigate other parameters for laterality assessment. Explanation of health aspects of left-handedness is dominantly based on Geschwind-Galaburda model about 'anomalous' cerebral domination, as a consequence of hormonal disbalance. .

  14. Left bundle-branch block

    DEFF Research Database (Denmark)

    Risum, Niels; Strauss, David; Sogaard, Peter;

    2013-01-01

    The relationship between myocardial electrical activation by electrocardiogram (ECG) and mechanical contraction by echocardiography in left bundle-branch block (LBBB) has never been clearly demonstrated. New strict criteria for LBBB based on a fundamental understanding of physiology have recently...

  15. Pentoxifylline Attenuates Cardiac Remodeling Induced by Tobacco Smoke Exposure

    Directory of Open Access Journals (Sweden)

    Marcos Minicucci

    2016-01-01

    Full Text Available Abstract Background: Tobacco smoke exposure is an important risk factor for cardiac remodeling. Under this condition, inflammation, oxidative stress, energy metabolism abnormalities, apoptosis, and hypertrophy are present. Pentoxifylline has anti‑inflammatory, anti-apoptotic, anti-thrombotic and anti-proliferative properties. Objective: The present study tested the hypothesis that pentoxifylline would attenuate cardiac remodeling induced by smoking. Methods: Wistar rats were distributed in four groups: Control (C, Pentoxifylline (PX, Tobacco Smoke (TS, and PX-TS. After two months, echocardiography, invasive blood pressure measurement, biochemical, and histological studies were performed. The groups were compared by two-way ANOVA with a significance level of 5%. Results: TS increased left atrium diameter and area, which was attenuated by PX. In the isolated heart study, TS lowered the positive derivate (+dp/dt, and this was attenuated by PX. The antioxidants enzyme superoxide dismutase and glutathione peroxidase were decreased in the TS group; PX recovered these activities. TS increased lactate dehydrogenase (LDH and decreased 3-hydroxyacyl Coenzyme A dehydrogenases (OH-DHA and citrate synthase (CS. PX attenuated LDH, 3-OH-DHA and CS alterations in TS-PX group. TS increased IL-10, ICAM-1, and caspase-3. PX did not influence these variables. Conclusion: TS induced cardiac remodeling, associated with increased inflammation, oxidative stress, apoptosis, and changed energy metabolism. PX attenuated cardiac remodeling by reducing oxidative stress and improving cardiac bioenergetics, but did not act upon cardiac cytokines and apoptosis.

  16. Why Am I Left-Handed?

    Science.gov (United States)

    ... does since most hitters are right-handed. In basketball and other sports, a left-handed player can ... change in strategy. For instance, a left-handed basketball player will dribble with his or her left ...

  17. To the Left or the Right?

    Institute of Scientific and Technical Information of China (English)

    ZHANGZHAOHUI

    2004-01-01

    THE Left Bank Gallery in the Zhongguancun area of Beijing's Haidian District unveiled “The Left-Wing” in late December 2003. The gallery housed the exhibit two huge concrete floors within a commercialreal estate project called Left Bank.

  18. Teratoma occupying the left hemithorax

    Directory of Open Access Journals (Sweden)

    Skevis Konstantinos

    2005-11-01

    Full Text Available Abstract Background Teratomas are manifested with a great variety of clinical and radiological features, while sometimes they simply represent incidental findings. Case presentation A rare case of benign teratoma of the dermoid cyst type, in an adult 40-year-old female patient, is reported. The patient had presented recurrent pulmonary infections for the previous 2 months, persistent cough, and progressively aggravating dyspnea. A chest X-ray showed total atelectasis of the left lung, and the thoracic CT-scan revealed a huge mass, containing multiple elements of heterogeneous density, probably originating from the mediastinum, occupying the whole left hemithorax. The mass compressed the vital structures of the mediastinum, great vessels and airways, and a chest MRI was performed to accurately detect the anatomical relations. The patient underwent left thoracotomy and the tumor was totally resected. The size of the tumor was extremely large although no invasion to the vessels or to the airway had occurred. Adherence to the adjacent left pulmonary artery and left main bronchus was present, but without erosion or fistulization. The postoperative course was uneventful, while the histological examination confirmed a teratoma. Conclusion A teratoma is a non-homogeneous pathological entity, clinically, radiologically or histologically. It is predominantly diagnosed between the second and fourth decade and the incidence is equal for both sexes. Symptoms are absent in one half of the patients. The case reported is noteworthy as the tumor appeared with total atelectasis of the left lung, and symptoms started 2 months prior to diagnosis. Total removal of the tumor is adequate treatment for this type of teratoma and the prognosis is excellent.

  19. Patient position alters attenuation effects in multipinhole cardiac SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Timmins, Rachel; Ruddy, Terrence D.; Wells, R. Glenn, E-mail: gwells@ottawaheart.ca [Division of Cardiology, University of Ottawa Heart Institute, Ottawa, Ontario K1Y 4W7 (Canada)

    2015-03-15

    Purpose: Dedicated cardiac cameras offer improved sensitivity over conventional SPECT cameras. Sensitivity gains are obtained by large numbers of detectors and novel collimator arrangements such as an array of multiple pinholes that focus on the heart. Pinholes lead to variable amounts of attenuation as a source is moved within the camera field of view. This study evaluated the effects of this variable attenuation on myocardial SPECT images. Methods: Computer simulations were performed for a set of nine point sources distributed in the left ventricular wall (LV). Sources were placed at the location of the heart in both an anthropomorphic and a water-cylinder computer phantom. Sources were translated in x, y, and z by up to 5 cm from the center. Projections were simulated with and without attenuation and the changes in attenuation were compared. A LV with an inferior wall defect was also simulated in both phantoms over the same range of positions. Real camera data were acquired on a Discovery NM530c camera (GE Healthcare, Haifa, Israel) for five min in list-mode using an anthropomorphic phantom (DataSpectrum, Durham, NC) with 100 MBq of Tc-99m in the LV. Images were taken over the same range of positions as the simulations and were compared based on the summed perfusion score (SPS), defect width, and apparent defect uptake for each position. Results: Point sources in the water phantom showed absolute changes in attenuation of ≤8% over the range of positions and relative changes of ≤5% compared to the apex. In the anthropomorphic computer simulations, absolute change increased to 20%. The changes in relative attenuation caused a change in SPS of <1.5 for the water phantom but up to 4.2 in the anthropomorphic phantom. Changes were larger for axial than for transverse translations. These results were supported by SPS changes of up to six seen in the physical anthropomorphic phantom for axial translations. Defect width was also seen to significantly increase. The

  20. Seismic attenuation in fractured media

    International Nuclear Information System (INIS)

    The prime objective of this paper is to quantitatively estimate seismic attenuation caused by fractures with different physical parameters. In seismic wave simulation, the fractured media are treated as the anisotropic media and fractures are represented by frequency-dependent elastic constants. Based on numerical experiments with three different parameters, namely viscosity, porosity and the Lamé parameters, this paper has the following observations. First, seismic attenuation is not affected by the viscosity within fractures, although it increases with the increase of porosity and decreases with the increase of the Lamé parameters within fractures. Among the latter two parameters, seismic attenuation is more sensitive to the Lamé parameters than to the porosity. Second, for the attenuation anisotropy, low frequencies have more anisotropic effect than high frequencies. For example, a 50 Hz wavefield has the strongest anisotropy effect if compared to 100 and 150 Hz wavefields. The attenuation anisotropy for low frequency (say 50 Hz) is more sensitive to the viscosity than the porosity and the Lamé parameters have the weakest effect among these three parameters. These observations suggest that low-frequency seismic attenuation, and especially the attenuation anisotropy in low frequency, would have great potential for fluid discrimination within fractured media. (paper)

  1. Mitochondria and left ventricular hypertrophy

    Institute of Scientific and Technical Information of China (English)

    Haiyan Zhu; Shiwen Wang

    2008-01-01

    @@ Introduction Left ventricular hypertrophy (LVH) is one of the vicious organ damages of essential hypertension.It contributes a lot to high mortality of essential hypertension due to sudden cardiac death,ventricular arrhythmia and heart failure.Many factors involve in the pathogenesis of hypertension-induced LVH including inherited variants as well as environmental factors.

  2. Transformation of Left Terminating Programs

    NARCIS (Netherlands)

    Bossi, Annalisa; Cocco, Nicoletta; Etalle, Sandro; Bossi, Annalisa

    2000-01-01

    We propose an unfold-fold transformation system which preserves left termination for definite programs besides its declarative semantics. The system extends our previous proposal in [BCE95] by allowing to switch the atoms in the clause bodies when a specific applicability condition is satisfied. The

  3. Syria divides the Arab left

    OpenAIRE

    Dot-Pouillard, Nicolas

    2012-01-01

    The violence deepens and spreads. Yet unlike Egypt and Tunisia, the Syrian revolt has not had unanimous support from the Arab left. There is a split between those who sympathise with the protestors' demands and those who fear foreign interference, both political and military

  4. Mechanics of left ventricular aneurysm.

    Science.gov (United States)

    Radhakrishnan, S; Ghista, D N; Jayaraman, G

    1986-01-01

    When a coronary artery is significantly occluded, the left ventricular myocardial segment, which is perfused by that coronary artery, will become ischaemic and even irreversibly infarcted. An acute infarct has very low stiffness and if it involves the entire wall there is a risk of rupture; however, in the absence of such a critical situation, fibrous tissue is laid into the infarcted myocardial segment. Such an infarcted fibrotic myocardial segment will not be able to contract, and so generate tensile stress. The surrounding intact myocardium will contract and generate wall stress, thereby developing a high intra-chamber systolic pressure; the chronically infarcted and fibrotic segment will have to sustain this high chamber pressure. Its loss of contractility and the resulting reduced systolic stiffness relative to the intact segment, will cause it to deform into a bulge; this is an aneurysm. When a left ventricular chamber with an aneurysm contracts during the systolic phase, some blood also goes into the aneurysm, and this decreases the stroke volume; since the aneurysm wall is passive, stagnant blood flow prevails in the aneurysm itself, which in turn can give rise to the formation of a mural thrombus. These serious consequences provide a justification for the analysis of an infarcted left ventricular chamber, in order to predict the size of the aneurysmic bulge. Such an analysis is presented in this paper. To determine the left ventricular wall deformation, and the stress arising from infarction of a wall segment (which leads to a ventricular aneurysm) the left ventricle is modelled here as a pressurized ellipsoidal shell. Deformations of infarcted wall segments are computed for several damaged wall-thicknesses in left ventricles of different shapes. The analysis involves a derivation of equations for wall-stress equilibrium with the chamber pressure, and myocardial incompressibility before and after infarct formation. The equations are solved by the Newton

  5. Low scale left-right-right-left symmetry

    CERN Document Server

    Abbas, Gauhar

    2016-01-01

    We propose an effective left-right-right-left model with a parity breaking scale around a few TeV. One of the main achievements of the model is that the mirror fermions as well as the mirror gauge sector simultaneously could be at TeV scale. It is shown that the most dangerous quadratic divergence of the SM Higgs boson involving the top quark in the loop is naturally suppressed atleast up to approximately $10$ TeV. This could lead to a sufficient parameter space in the scalar potential to make the SM Higgs mass natural even up to the Planck scale. An elegant symmetry breaking pattern is also proposed.

  6. Right-handed and left-landed

    Institute of Scientific and Technical Information of China (English)

    李悦

    2005-01-01

    Today about 15% of the number of people is left-handed.But why are people left-handed? The answer is the way the brain (大脑) works.The brain has two halves——the right half and the left half.The right half controls (控制)the left side of the body,and the left controls the right side of the body.

  7. Systolic left ventricular function according to left ventricular concentricity and dilatation in hypertensive patients

    DEFF Research Database (Denmark)

    Bang, Casper; Gerdts, Eva; Aurigemma, Gerard P;

    2013-01-01

    Left ventricular hypertrophy [LVH, high left ventricular mass (LVM)] is traditionally classified as concentric or eccentric based on left ventricular relative wall thickness. We evaluated left ventricular systolic function in a new four-group LVH classification based on left ventricular dilatatio...

  8. Electroacupuncture attenuates neuropathic pain after brachial plexus injury

    Institute of Scientific and Technical Information of China (English)

    Shenyu Zhang; Hailiang Tang; Junming Zhou; Yudong Gu

    2014-01-01

    Electroacupuncture has traditionally been used to treat pain, but its effect on pain following brachial plexus injury is still unknown. In this study, rat models of an avulsion injury to the left brachial plexus root (associated with upper-limb chronic neuropathic pain) were given electroacu-puncture stimulation at bilateralQuchi(LI11),Hegu(LI04),Zusanli(ST36) andYanglingquan (GB34). After electroacupuncture therapy, chronic neuropathic pain in the rats’ upper limbs was signiifcantly attenuated. Immunolfuorescence staining showed that the expression of β-endorphins in the arcuate nucleus was signiifcantly increased after therapy. Thus, experimental ifndings indi-cate that electroacupuncture can attenuate neuropathic pain after brachial plexus injury through upregulatingβ-endorphin expression.

  9. Backscatter and attenuation characterization of ventricular myocardium

    Science.gov (United States)

    Gibson, Allyson Ann

    2009-12-01

    This Dissertation presents quantitative ultrasonic measurements of the myocardium in fetal hearts and adult human hearts with the goal of studying the physics of sound waves incident upon anisotropic and inhomogeneous materials. Ultrasound has been used as a clinical tool to assess heart structure and function for several decades. The clinical usefulness of this noninvasive approach has grown with our understanding of the physical mechanisms underlying the interaction of ultrasonic waves with the myocardium. In this Dissertation, integrated backscatter and attenuation analyses were performed on midgestational fetal hearts to assess potential differences in the left and right ventricular myocardium. The hearts were interrogated using a 50 MHz transducer that enabled finer spatial resolution than could be achieved at more typical clinical frequencies. Ultrasonic data analyses demonstrated different patterns and relative levels of backscatter and attenuation from the myocardium of the left ventricle and the right ventricle. Ultrasonic data of adult human hearts were acquired with a clinical imaging system and quantified by their magnitude and time delay of cyclic variation of myocardial backscatter. The results were analyzing using Bayes Classification and ROC analysis to quantify potential advantages of using a combination of two features of cyclic variation of myocardial backscatter over using only one or the other feature to distinguish between groups of subjects. When the subjects were classified based on hemoglobin A1c, the homeostasis model assessment of insulin resistance, and the ratio of triglyceride to high-density lipoprotein-cholesterol, differences in the magnitude and normalized time delay of cyclic variation of myocardial backscatter were observed. The cyclic variation results also suggested a trend toward a larger area under the ROC curve when information from magnitude and time delay of cyclic variation is combined using Bayes classification than when

  10. Estimation of Water Vapour Attenuation And Rain Attenuation

    Directory of Open Access Journals (Sweden)

    K.Kalyana Srinivas

    2015-04-01

    Full Text Available Attenuation due to and water vapour and rain can severely degrade the radio wave propagation at centimeter or millimeter wavelengths. It restricts the path length of radio communication systems and limits the use of higher frequencies for line-of-sight microwave links and satellite communications. The attenuation will pose a greater problem to communication as the frequency of occurrence of heavy rain increases.In a tropical region, like Malaysia, where excessive rainfall is a common phenomenon throughout the year, the knowledge of the rain attenuation at the frequency of operation is extremely required for the design of a reliable terrestrial and earth space communication link at a particular location.

  11. The attenuation and the attenuators: strategies and tactics

    Directory of Open Access Journals (Sweden)

    Antonio Briz

    2013-12-01

    Full Text Available This work is inscribed in a research project (ES.POR.ATENUAÇÃO that seeks to analyze and explain the attenuator activity in different regional varieties of Spanish and Portuguese, in order to perform, subsequently, different contrastive intralinguistic and interlinguistic studies. In this article, we explain some of the theoretical and methodological principles on which are based the qualitative and quantitative analysis. And especially, we will refer to the concept of attenuation (Briz 1995, 2002, 2003, 2005, 2007a, 2012.

  12. Multi-transmitting formula for attenuating waves

    Institute of Scientific and Technical Information of China (English)

    陈少林; 廖振鹏

    2003-01-01

    The MTF is extended to case of attenuating incident wave by introducing an attenuation coefficient. The reflection coefficients of this modified MTF and MTF areevaluated and compared when an attenuating wave impinges on the boundary, and the results demonstrate that MTF can be used to absorb slightly attenuating wavesand the modified MTF is more capable of absorbing heavily attenuating waves than MTF. The accuracy of modified MTF is also tested by numerical examples of fluid saturated porous media.

  13. Photoacoustic Imaging Taking into Account Attenuation

    CERN Document Server

    Kowar, Richard

    2010-01-01

    First, we review existing attenuation models and discuss their causality properties, which we believe to be essential for algorithms for inversion with attenuated data. Then, we survey causality properties of common attenuation models. We also derive integro-differential equations which the attenuated waves are satisfying. In addition we discuss the ill--conditionness of the inverse problem for calculating the unattenuated wave from the attenuated one.

  14. Left atrial ball valve thrombus

    Directory of Open Access Journals (Sweden)

    R. Balaji

    2013-10-01

    Full Text Available "Ball valve thrombus" which is a spherical free floating clot in left atrium is an often quoted, but uncommonly encountered complication in patients with severe mitral stenosis of rheumatic origin, who are in atrial fibrillation. We describe the case of a 31-year-old lady with rheumatic heart disease, severe mitral stenosis and moderately severe aortic stenosis who had undergone closed mitral valvotomy 13 years ago. The patient presented with an episode of non-exertional syncope and breathlessness on exertion of 6 months duration and was in normal sinus rhythm. Echocardiography facilitated ante-mortem diagnosis and prompt institution of surgery was life saving.

  15. Sound attenuation in magnetorheological fluids

    Science.gov (United States)

    Rodríguez-López, J.; Elvira, L.; Resa, P.; Montero de Espinosa, F.

    2013-02-01

    In this work, the attenuation of ultrasonic elastic waves propagating through magnetorheological (MR) fluids is analysed as a function of the particle volume fraction and the magnetic field intensity. Non-commercial MR fluids made with iron ferromagnetic particles and two different solvents (an olive oil based solution and an Araldite-epoxy) were used. Particle volume fractions of up to 0.25 were analysed. It is shown that the attenuation of sound depends strongly on the solvent used and the volume fraction. The influence of a magnetic field up to 212 mT was studied and it was found that the sound attenuation increases with the magnetic intensity until saturation is reached. A hysteretic effect is evident once the magnetic field is removed.

  16. Josephson tunnel junction microwave attenuator

    DEFF Research Database (Denmark)

    Koshelets, V. P.; Shitov, S. V.; Shchukin, A. V.;

    1993-01-01

    A new element for superconducting electronic circuitry-a variable attenuator-has been proposed, designed, and successfully tested. The principle of operation is based on the change in the microwave impedance of a superconductor-insulator-superconductor (SIS) Josephson tunnel junction when dc biased...... at different points in the current-voltage characteristic. Both numerical calculations based on the Tien-Gordon theory and 70-GHz microwave experiments have confirmed the wide dynamic range (more than 15-dB attenuation for one stage) and the low insertion loss in the ''open'' state. The performance of a fully...... integrated submillimeter receiver circuit which comprises a flux-flow oscillator (FFO) as local oscillator, a superconducting variable attenuator, and a microwave SIS detector with tuned-out capacitance is also reported....

  17. The Semigroup Structure of Left Clifford Semirings

    Institute of Scientific and Technical Information of China (English)

    Yu Qi GUO; Kar Ping SHUM; M. K. SEN

    2003-01-01

    In this paper, we generalize Clifford semirings to left Clifford semirings by means of theso-called band semirings. We also discuss a special case of this kind of semirings, that is, strongdistributive lattices of left rings.

  18. Left Septal Fascicular Block: Myth Or Reality?

    OpenAIRE

    MacAlpin, Rex N.

    2003-01-01

    Anatomic studies have shown that the left bundle branch divides into three fascicles in most humans. Changes in the 12 lead ECG (electrocardiogram) due to conduction abnormalities of the left anterior fascicle and left posterior fascicle are now part of the standard repertoire of electrocardiographic interpretation. There are no standard criteria for detecting conduction defects involving the third left fascicle, the septal or median fascicle, and the very existence of such defects is still a...

  19. X-Ray Attenuation Cell

    Energy Technology Data Exchange (ETDEWEB)

    Ryutov, D.; Toor, A.

    2000-03-03

    To minimize the pulse-to-pulse variation, the LCLS FEL must operate at saturation, i.e. 10 orders of magnitude brighter spectral brilliance than 3rd-generation light sources. At this intensity, ultra-high vacuums and windowless transport are required. Many of the experiments, however, will need to be conducted at a much lower intensity thereby requiring a reliable means to reduce the x-ray intensity by many orders of magnitude without increasing the pulse-to-pulse variation. In this report we consider a possible solution for controlled attenuation of the LCLS x-ray radiation. We suggest using for this purpose a windowless gas-filled cell with the differential pumping. Although this scheme is easily realizable in principle, it has to be demonstrated that the attenuator can be made short enough to be practical and that the gas loads delivered to the vacuum line of sight (LOS) are acceptable. We are not going to present a final, optimized design. Instead, we will provide a preliminary analysis showing that the whole concept is robust and is worth further study. The spatial structure of the LCLS x-ray pulse at the location of the attenuator is shown in Fig. 1. The central high-intensity component, due to the FEL, has a FWHM of {approx}100 {micro}m. A second component, due to the undulator's broad band spontaneous radiation is seen as a much lower intensity ''halo'' with a FWHM of 1 mm. We discuss two versions of the attenuation cell. The first is directed towards a controlled attenuation of the FEL up to the 4 orders of magnitude in the intensity, with the spontaneous radiation halo being eliminated by collimators. In the second version, the spontaneous radiation is not sacrificed but the FEL component (as well as the first harmonic of the spontaneous radiation) gets attenuated by a more modest factor up to 100. We will make all the estimates assuming that the gas used in the attenuator is Xenon and that the energy of the FEL is 8.25 keV. At

  20. Left Supraclavicular Spindle Cell Lipoma

    Directory of Open Access Journals (Sweden)

    Oladejo Olaleye

    2010-01-01

    This case highlights a rare presentation of SCL and the need for pre-operative diagnosis. Case Report. A 63-year-old gentleman presented with a pre-existing left supraclavicular mass that had recently increased in size. FNA and CT Scans were performed and results discussed in the mutidisciplinary team meeting. Excisional biopsy was recommended. Radiology. CT neck showed a left supraclavicular mass of fatty density with fine internal septations. A low-grade liposarcoma could not be excluded. Histopathology. FNA was indeterminate. Histology of specimen showed bland spindle cells with no evidence of malignancy. Immuno-histochemistry showed SCL with CD34 positivity and negative staining on CDK4 and p16. Management. Excision biopsy of the mass was performed which was technically difficult as the mass invaginated around the brachial plexus. The patient recovered well post-operatively with no neurological deficits. Conclusion. Spindle cell lipoma is a rare benign tumour and a pre-operative diagnosis based on the clinical context, imaging and immuno-histochemistry is crucial to management.

  1. Bicyclic semigroups of left I-quotients

    CERN Document Server

    Ghroda, Nassraddin

    2011-01-01

    In this article we study left I-orders in the bicyclic monoid $\\mathcal{B}$. We give necessary and sufficient conditions for a subsemigroup of $\\mathcal{B}$ to be a left I-oreder in $\\mathcal{B}$. We then prove that any left I-order in $\\mathcal{B}$ is straight.

  2. Left-handed Children in Singapore.

    Science.gov (United States)

    Gan, Linda

    1998-01-01

    Used teacher questionnaires to examine incidence of left-handedness in nearly 2,800 Singaporean children, racial differences in this left-handed population, and educational provisions in preschool and primary school. Findings indicated that 7.5% of preschoolers and 6.3% of primary children were left-handed, with a higher proportion being Chinese…

  3. The Left-Handed: "Their Sinister" History.

    Science.gov (United States)

    Costas, Elaine Fowler

    The history of left-handedness can provide teachers and parents a better understanding of left-handed children and give those children more pride in their difference. No child should be made to feel that he or she is abnormal because of using the left hand, although some specific instruction for these students is necessary in handwriting. Many…

  4. Diabetes, gender, and left ventricular structure in African-Americans: the atherosclerosis risk in communities study

    Directory of Open Access Journals (Sweden)

    Liebson Philip R

    2006-11-01

    Full Text Available Abstract Background Cardiovascular risk associated with diabetes may be partially attributed to left ventricular structural abnormalities. However, the relations between left ventricular structure and diabetes have not been extensively studied in African-Americans. Methods We studied 514 male and 965 female African-Americans 51 to 70 years old, in whom echocardiographic left ventricular mass measurements were collected for the ARIC Study. In these, we investigated the independent association of diabetes with left ventricular structural abnormalities. Results Diabetes, hypertension and obesity prevalences were 22%, 57% and 45%, respectively. Unindexed left ventricular mass was higher with diabetes in both men (238.3 ± 79.4 g vs. 213.7 ± 58.6 g; p Conclusion In African-Americans, diabetes is associated with left ventricular hypertrophy and, with different patterns of left ventricular structural abnormalities between genders. Attenuation seen in adjusted associations suggests that the higher frequency of structural abnormalities seen in diabetes may be due to factors other than hyperglycemia.

  5. Left-handed wrestlers are more successful.

    Science.gov (United States)

    Ziyagil, Mehmet Akif; Gursoy, Recep; Dane, Senol; Yuksel, Ramazan

    2010-08-01

    It has been reported that there is a high proportion of left-handers among top athletes in different sports. In this study, the goal was to examine the rate of left-handedness in the top wrestlers at the world championships for achievement by left-handed wrestlers. The rate of left-handedness was higher in wrestlers with medal honors compared to wrestlers without medals for both men and women. The winning numbers and match degrees were higher in the left-handed wrestlers than in both right- and mixed-handed wrestlers among top international wrestlers.

  6. Compact plasmonic variable optical attenuator

    DEFF Research Database (Denmark)

    Leosson, Kristjan; Rosenzveig, Tiberiu; Hermannsson, Pétur Gordon;

    2008-01-01

    We demonstrate plasmonic nanowire-based thermo-optic variable optical attenuators operating in the 1525-1625 nm wavelength range. The devices have a footprint as low as 1 mm, extinction ratio exceeding 40 dB, driving voltage below 3 V, and full modulation bandwidth of 1 kHz. The polarization...

  7. Mirror left-right symmetry

    International Nuclear Information System (INIS)

    We propose a novel SU(3)c×SU(2)L×SU(2)R×U(1)B-L left-right symmetric model where the standard model fermion and Higgs fields are SU(2)L doublets or SU(2) singlets while their mirror partners are SU(2)R doublets or SU(2) singlets. The scalar fields also include a real singlet for dark matter and two SU(2) triplets for seesaw. The mixing between the standard model and mirror fermions is forbidden by a Z2×Z2′ discrete symmetry. The mirror charged fermions can decay into their standard model partners with the dark-matter scalar while the mirror neutrinos can decay into the mirror charged fermions through the right-handed gauge interactions. Our model can have new implications on the strong CP problem, leptogenesis, collider phenomenology and dark matter detection.

  8. Giant and thrombosed left ventricular aneurysm

    Institute of Scientific and Technical Information of China (English)

    Jose; Alberto; de; Agustin; Jose; Juan; Gomez; de; Diego; Pedro; Marcos-Alberca; Jose; Luis; Rodrigo; Carlos; Almeria; Patricia; Mahia; Maria; Luaces; Miguel; Angel; Garcia-Fernandez; Carlos; Macaya; Leopoldo; Perez; de; Isla

    2015-01-01

    Left ventricular aneurysms are a frequent complication of acute extensive myocardial infarction and are most commonly located at the ventricular apex. A timely diagnosis is vital due to the serious complications that can occur,including heart failure,thromboembolism,or tachyarrhythmias. We report the case of a 78-yearold male with history of previous anterior myocardial infarction and currently under evaluation by chronic heart failure. Transthoracic echocardiogram revealed a huge thrombosed and calcified anteroapical left ventricular aneurysm. Coronary angiography demonstrated that the left anterior descending artery was chronically occluded,and revealed a big and spherical mass with calcified borders in the left hemithorax. Left ventriculogram confirmed that this spherical mass was a giant calcified left ventricular aneurysm,causing very severe left ventricular systolic dysfunction. The patient underwent cardioverter-defibrillator implantation for primary prevention.

  9. Giant and thrombosed left ventricular aneurysm.

    Science.gov (United States)

    de Agustin, Jose Alberto; de Diego, Jose Juan Gomez; Marcos-Alberca, Pedro; Rodrigo, Jose Luis; Almeria, Carlos; Mahia, Patricia; Luaces, Maria; Garcia-Fernandez, Miguel Angel; Macaya, Carlos; de Isla, Leopoldo Perez

    2015-07-26

    Left ventricular aneurysms are a frequent complication of acute extensive myocardial infarction and are most commonly located at the ventricular apex. A timely diagnosis is vital due to the serious complications that can occur, including heart failure, thromboembolism, or tachyarrhythmias. We report the case of a 78-year-old male with history of previous anterior myocardial infarction and currently under evaluation by chronic heart failure. Transthoracic echocardiogram revealed a huge thrombosed and calcified anteroapical left ventricular aneurysm. Coronary angiography demonstrated that the left anterior descending artery was chronically occluded, and revealed a big and spherical mass with calcified borders in the left hemithorax. Left ventriculogram confirmed that this spherical mass was a giant calcified left ventricular aneurysm, causing very severe left ventricular systolic dysfunction. The patient underwent cardioverter-defibrillator implantation for primary prevention.

  10. Asymptomatic post-rheumatic giant left atrium.

    Science.gov (United States)

    Özkartal, Tardu; Tanner, Felix C; Niemann, Markus

    2016-06-26

    A 78-year-old asymptomatic woman was referred to our clinic for a second opinion regarding indication for mitral valve surgery. An echocardiogram showed a moderate mitral stenosis with a concomitant severe regurgitation. The most striking feature, however, was a giant left atrium with a parasternal anteroposterior diameter of 79 mm and a left atrial volume index of 364 mL/m². There are various echocardiographic definitions of a giant left atrium, which are mainly based on measurements of the anteroposterior diameter of the left atrium using M-mode in the parasternal long axis view. Since the commonly accepted method for echocardiographic evaluation of left atrial size is left atrial volume index, we propose a cut-off value of 140 mL/m(2) for the definition of a "giant left atrium".

  11. ENHANCEMENTS TO NATURAL ATTENUATION: SELECTED CASE STUDIES

    Energy Technology Data Exchange (ETDEWEB)

    Vangelas, K; W. H. Albright, W; E. S. Becvar, E; C. H. Benson, C; T. O. Early, T; E. Hood, E; P. M. Jardine, P; M. Lorah, M; E. Majche, E; D. Major, D; W. J. Waugh, W; G. Wein, G; O. R. West, O

    2007-05-15

    In 2003 the US Department of Energy (DOE) embarked on a project to explore an innovative approach to remediation of subsurface contaminant plumes that focused on introducing mechanisms for augmenting natural attenuation to achieve site closure. Termed enhanced attenuation (EA), this approach has drawn its inspiration from the concept of monitored natural attenuation (MNA).

  12. SEISMIC ATTENUATION FOR RESERVOIR CHARACTERIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Joel Walls; M.T. Taner; Gary Mavko; Jack Dvorkin

    2002-01-01

    In Section 1 of this first report we will describe the work we are doing to collect and analyze rock physics data for the purpose of modeling seismic attenuation from other measurable quantities such as porosity, water saturation, clay content and net stress. This work and other empirical methods to be presented later, will form the basis for ''Q pseudo-well modeling'' that is a key part of this project. In Section 2 of this report, we will show the fundamentals of a new method to extract Q, dispersion, and attenuation from field seismic data. The method is called Gabor-Morlet time-frequency decomposition. This technique has a number of advantages including greater stability and better time resolution than spectral ratio methods.

  13. Chlorine signal attenuation in concrete.

    Science.gov (United States)

    Naqvi, A A; Maslehuddin, M; ur-Rehman, Khateeb; Al-Amoudi, O S B

    2015-11-01

    The intensity of prompt gamma-ray was measured at various depths from chlorine-contaminated silica fume (SF) concrete slab concrete specimens using portable neutron generator-based prompt gamma-ray setup. The intensity of 6.11MeV chloride gamma-rays was measured from the chloride contaminated slab at distance of 15.25, 20.25, 25.25, 30.25 and 35.25cm from neutron target in a SF cement concrete slab specimens. Due to attenuation of thermal neutron flux and emitted gamma-ray intensity in SF cement concrete at various depths, the measured intensity of chlorine gamma-rays decreases non-linearly with increasing depth in concrete. A good agreement was noted between the experimental results and the results of Monte Carlo simulation. This study has provided useful experimental data for evaluating the chloride contamination in the SF concrete utilizing gamma-ray attenuation method.

  14. Abnormal functioning of the left temporal lobe in language-impaired children.

    Science.gov (United States)

    Helenius, Päivi; Sivonen, Päivi; Parviainen, Tiina; Isoaho, Pia; Hannus, Sinikka; Kauppila, Timo; Salmelin, Riitta; Isotalo, Leena

    2014-03-01

    Specific language impairment is associated with enduring problems in language-related functions. We followed the spatiotemporal course of cortical activation in SLI using magnetoencephalography. In the experiment, children with normal and impaired language development heard spoken real words and pseudowords presented only once or two times in a row. In typically developing children, the activation in the bilateral superior temporal cortices was attenuated to the second presentation of the same word. In SLI children, this repetition effect was nearly nonexistent in the left hemisphere. Furthermore, the activation was equally strong to words and pseudowords in SLI children whereas in the typically developing children the left hemisphere activation persisted longer for pseudowords than words. Our results indicate that the short-term maintenance of linguistic activation that underlies spoken word recognition is defective in SLI particularly in the left language-dominant hemisphere. The unusually rapid decay of speech-evoked activation can contribute to impaired vocabulary growth.

  15. Hyperglycemia impairs left-right axis formation and thereby disturbs heart morphogenesis in mouse embryos.

    Science.gov (United States)

    Hachisuga, Masahiro; Oki, Shinya; Kitajima, Keiko; Ikuta, Satomi; Sumi, Tomoyuki; Kato, Kiyoko; Wake, Norio; Meno, Chikara

    2015-09-22

    Congenital heart defects with heterotaxia are associated with pregestational diabetes mellitus. To provide insight into the mechanisms underlying such diabetes-related heart defects, we examined the effects of high-glucose concentrations on formation of the left-right axis in mouse embryos. Expression of Pitx2, which plays a key role in left-right asymmetric morphogenesis and cardiac development, was lost in the left lateral plate mesoderm of embryos of diabetic dams. Embryos exposed to high-glucose concentrations in culture also failed to express Nodal and Pitx2 in the left lateral plate mesoderm. The distribution of phosphorylated Smad2 revealed that Nodal activity in the node was attenuated, accounting for the failure of left-right axis formation. Consistent with this notion, Notch signal-dependent expression of Nodal-related genes in the node was also down-regulated in association with a reduced level of Notch signaling, suggesting that high-glucose concentrations impede Notch signaling and thereby hinder establishment of the left-right axis required for heart morphogenesis. PMID:26351675

  16. Mechanisms of geometrical seismic attenuation

    Directory of Open Access Journals (Sweden)

    Igor B. Morozov

    2011-07-01

    Full Text Available In several recent reports, we have explained the frequency dependence of the apparent seismic quality-factor (Q observed in many studies according to the effects of geometrical attenuation, which was defined as the zero-frequency limit of the temporal attenuation coefficient. In particular, geometrical attenuation was found to be positive for most waves traveling within the lithosphere. Here, we present three theoretical models that illustrate the origin of this geometrical attenuation, and we investigate the causes of its preferential positive values. In addition, we discuss the physical basis and limitations of both the conventional and new attenuation models. For waves in media with slowly varying properties, geometrical attenuation is caused by variations in the wavefront curvature, which can be both positive (for defocusing and negative (for focusing. In media with velocity/density contrasts, incoherent reflectivity leads to geometrical-attenuation coefficients which are proportional to the mean squared reflectivity and are always positive. For «coherent» reflectivity, the geometrical attenuation is approximately zero, and the attenuation process can be described according to the concept of «scattering Q». However, the true meaning of this parameter is in describing the mean reflectivity within the medium, and not that of the traditional resonator quality factor known in mechanics. The general conclusion from these models is that non-zero and often positive levels of geometrical attenuation are common in realistic, heterogeneous media, both observationally and theoretically. When transformed into the conventional Q-factor form, this positive geometrical attenuation leads to Q values that quickly increase with frequency. These predictions show that the positive frequency-dependent Q observed in many datasets might represent artifacts of the transformations of the attenuation coefficients into Q.

  1. Left handedness and Leadership in Interactive Contests

    CERN Document Server

    Mukherjee, Satyam

    2013-01-01

    Left-handedness is known to provide an advantage at top level at many sports involving interactive contests. Earlier studies revealed that this is because of the innate superiority of left-handed contestants. Again, most of the renowned leaders of the world are known to have been left-handed. We analyze the data of batting and bowling performance in Cricket and verify the advantage of left-handedness for batsmen. For bowlers, left-handedness provide no advantage. Leadership play an important role in politics, sports and mentorship. In this paper we show that Cricket captains who bat left-handed have a strategic advantage over the right-handed captains in Test cricket. Our results demonstrate that critical importance of left-handedness and successful leadership. Our study shows that left-handed captains lead in more number of games and are significantly more successful than right-handed captains . Interestingly left-handed captains have a higher batting average than the right-handed counterparts, perhaps indic...

  2. Lipschitz $\\left(\\mathfrak{m}^L\\left(s;q\\right),p\\right)$ and $\\left(p,\\mathfrak{m}^L\\left(s;q\\right)\\right)-$summing maps

    OpenAIRE

    Salah, Manaf Adnan

    2013-01-01

    Building upon the linear version of mixed summable sequences in arbitrary Banach spaces of A. Pietsch, we introduce a nonlinear version of his concept and study its properties. Extending previous work of J. D. Farmer, W. B. Johnson and J. A. Ch\\'avez-Dom\\'inguez, we define Lipschitz $\\left(\\mathfrak{m}^L\\left(s;q\\right),p\\right)$ and Lipschitz $\\left(p,\\mathfrak{m}^L\\left(s;q\\right)\\right)-$summing maps and establish inclusion theorems, composition theorems and several characterizations. Furt...

  3. Left Ventricular Thrombosis in Ulcerative Colitis

    Directory of Open Access Journals (Sweden)

    Tarek Saleh

    2010-07-01

    Full Text Available Left ventricular thrombi usually occur in the setting of an acute myocardial infarction, left ventricular aneurysm, or dilated cardiomyopathy. In the absence of ventricular wall motion abnormalities, they are rare. This report describes a patient with ulcerative colitis in whom two-dimensional echocardiography revealed a left intraventricular mass. Thrombosis in ulcerative colitis is a serious condition and can occur in a very young population. This case also shows that left ventricular thrombi can occur in the active setting of ulcerative colitis.

  4. Attenuation in silica-based optical fibers

    DEFF Research Database (Denmark)

    Wandel, Marie Emilie

    2006-01-01

    absorption peaks in order to investigate the cause of an unusual high attenuation in a series of transmission fibers. Strong indications point to Ni2+ in octahedral coordination as being the cause of the high attenuation. The attenuation of fibers having a high core refractive index is analyzed and the cause...... well as the viscosity profile a lower attenuation of high index fibers can be obtained. The design of dispersion compensating fibers using the super mode approach is described, the object being to design dispersion compensating fibers for dispersion compensating fiber modules having a low attenuation......, described by a high figure of merit. The major trade offs encountered when designing dispersion compensating fibers with high figure of merit are to obtain a very negative dispersion, low attenuation and low micro bend loss at the same time. The model for predicting the attenuation of high index fibers is...

  5. “Getting the Left Right”

    DEFF Research Database (Denmark)

    Klinke, Marianne E.; Zahavi, Dan; Hjaltason, Haukur;

    2015-01-01

    experience was captured in the overarching theme, “getting the left right,” which encompasses the two subthemes of (a) surreal awareness of the left and (b) emergence of a different world. Patients had unclear perceptions of their own body and surroundings, their attention was brittle, and they encountered...

  6. Pure Left Neglect for Arabic Numerals

    Science.gov (United States)

    Priftis, Konstantinos; Albanese, Silvia; Meneghello, Francesca; Pitteri, Marco

    2013-01-01

    Arabic numerals are diffused and language-free representations of number magnitude. To be effectively processed, the digits composing Arabic numerals must be spatially arrangspan>ed along a left-to-right axis. We studied one patient (AK) to show that left neglect, after right hemisphere damage, can selectively impair the computation of the spatial…

  7. Malignant phyllodes tumor of the left atrium.

    Science.gov (United States)

    Bhambhani, Anupam; Ayyagari, Sudha; Mohapatra, Tushar; Rehman, Syed Abdul; Shah, Milap; Rao, Sudhakar; Rangashamanna, Vital; Rajasekhar, V; Chittimilla, Santosh

    2014-01-01

    Metastatic tumors to the heart usually involve right sided chambers. We report a rare case of malignant phyllodes tumor of breast with metastatic involvement of left atrium occurring through direct invasion from mediastinal micro-metastasis and presenting as a left atrial mass causing arrhythmia. PMID:24814127

  8. Pure Left Neglect for Arabic Numerals

    Science.gov (United States)

    Priftis, Konstantinos; Albanese, Silvia; Meneghello, Francesca; Pitteri, Marco

    2013-01-01

    Arabic numerals are diffused and language-free representations of number magnitude. To be effectively processed, the digits composing Arabic numerals must be spatially arranged along a left-to-right axis. We studied one patient (AK) to show that left neglect, after right hemisphere damage, can selectively impair the computation of the spatial…

  9. Left Paraduodenal Hernia: An Autopsy Case

    DEFF Research Database (Denmark)

    Omland, Silje Haukali; Hougen, Hans Petter

    2011-01-01

    We present a case of a left paraduodenal hernia diagnosed at autopsy. A left paraduodenal hernia is an internal hernia of congenital origin due to the abnormal rotation of the midgut during embryonic development. Internal hernias are a rare cause of intestinal obstruction, with the paraduodenal...

  10. A Study of $\\left(\\lambda ,\\mu \\right)$ -Fuzzy Subgroups

    OpenAIRE

    Li, Yuying; Wang, Xuzhu; Yang, Liqiong

    2013-01-01

    We deal with topics regarding $\\left(\\lambda ,\\mu \\right)$ -fuzzy subgroups, mainly $\\left(\\lambda ,\\mu \\right)$ -fuzzy cosets and $\\left(\\lambda ,\\mu \\right)$ -fuzzy normal subgroups. We give basic properties of $\\left(\\lambda ,\\mu \\right)$ -fuzzy subgroups and present some results related to $\\left(\\lambda ,\\mu \\right)$ -fuzzy cosets and $\\left(\\lambda ,\\mu \\right)$ -fuzzy normal subgroups.

  11. A rare case of left superior vena cava draining into left atrium demonstrated by MDCT.

    Science.gov (United States)

    Ardilouze, Paul; Bricot, Vincent; Maurel, Christophe; Christiaens, Luc

    2009-01-01

    We describe a rare case of persistent left superior vena cava draining directly into the left atrium with no associated anomaly of the coronary sinus or the atrial septum, discovered by multidetector computed tomography. PMID:17692952

  12. Sliding thin slab, minimum intensity projection of the lung in asymptomatic subjects: lower limits of lung attenuation, without airways

    International Nuclear Information System (INIS)

    A sliding thin slab, minimum intensity projection (STS-MinIP) is considered to be useful for detecting diseases that decrease lung attenuation. For evaluating these diseases, it would be useful to ascertain the lower limits of normal lung attenuation, allowing a division between normal and subnormal attenuation. However, normal lung attenuation may vary depending on respiratory status, anatomical position, and patient background factors. Our aim was to determine whether the lower limits of lung attenuation, without airways, in asymptomatic subjects using STS-MinIP varies under different conditions. The study subjects were 43 volunteers without pulmonary symptoms. STS-MinIP was performed at full inspiration and full expiration at three levels of the lung. The lower limits of lung attenuation were compared among the three lung levels and between full inspiration and full expiration, the sexes, age groups, smokers and nonsmokers, and the right and left lungs. The lower limits of lung attenuation had significantly different Hounsfield unit values among lung levels, between the sexes at full inspiration, and between age groups at full expiration. This study shows that the lower limits of lung attenuation are influenced by lung fields, sex, and, on expiration, age. (author)

  13. Anomalous origin of left vertebral artery

    Directory of Open Access Journals (Sweden)

    Veena Vidya Shankar

    2013-01-01

    Full Text Available Vertebral artery arises from the upper surface of the first part of subclavian artery on both sides. The morphological variations of the vertebral artery are of immense importance in surgery, angiography and all non-invasive procedures. During the routine dissection of a male cadaver aged about 65 years, we observed a variation in the branching of arch of aorta. The arch of aorta gave off four branches-brachiocephalic trunk, left common carotid artery (CCA, left vertebral artery (LVA and left subclavian artery. LVA was arising between left CCA and left subclavian artery.The knowledge of variations in the vertebral artery is of great clinical interest to the neurosurgeon and radiologist for diagnostic investigation and surgical procedures of the neck.

  14. A giant left main trunk and left circumflex artery-to-right ventricle fistula

    Directory of Open Access Journals (Sweden)

    Zhao-hui Peng

    2014-01-01

    Full Text Available Coronary artery fistula including the left trunk and left circumflex is uncommon. We present a 24-year-old male patient with a giant left main trunk and left circumflex artery to right ventricle fistula, which is diagnosed by transthoracic echocardiography and coronary computed tomography angiography. In this paper, the case report is to provide a better understanding of clinical characteristics for this disease.

  15. VARIATION IN THE OPENINGS (OSTIA OF LEFT PULMONARY VEINS INTO THE LEFT ATRIUM: A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Sesi

    2015-03-01

    Full Text Available During early embryonic development, absorption of pulmonary venous network by the left primitive atrial chamber results in opening of four pulmonary veins which drain independently into its chamber. The extent of absorption and hence, the number of pulmon ary veins which open into the left atrium, may vary. Here we report a variation in the opening of the Left upper (superior pulmonary vein into the Left atrium. A total of six openings observed

  16. Left-Deviating Prism Adaptation in Left Neglect Patient: Reflexions on a Negative Result

    OpenAIRE

    Jacques Luauté; Sophie Jacquin-Courtois; Jacinta O'Shea; Laure Christophe; Gilles Rode; Dominique Boisson; Yves Rossetti

    2012-01-01

    Adaptation to right-deviating prisms is a promising intervention for the rehabilitation of patients with left spatial neglect. In order to test the lateral specificity of prism adaptation on left neglect, the present study evaluated the effect of left-deviating prism on straight-ahead pointing movements and on several classical neuropsychological tests in a group of five right brain-damaged patients with left spatial neglect. A group of healthy subjects was also included for comparison purpos...

  17. TMS over the Left Angular Gyrus Impairs the Ability to Discriminate Left from Right

    Science.gov (United States)

    Hirnstein, Marco; Bayer, Ulrike; Ellison, Amanda; Hausmann, Markus

    2011-01-01

    The underlying cognitive and neural mechanisms of the ability to discriminate left from right are hardly explored. Clinical studies from patients with impairments of left-right discrimination (LRD) and neuroimaging data suggest that the left angular gyrus is particularly involved in LRD. Moreover, it is argued that the often reported sex…

  18. Imaging Rayleigh wave attenuation with USArray

    Science.gov (United States)

    Bao, Xueyang; Dalton, Colleen A.; Jin, Ge; Gaherty, James B.; Shen, Yang

    2016-07-01

    The EarthScope USArray provides an opportunity to obtain detailed images of the continental upper mantle at an unprecedented scale. The majority of mantle models derived from USArray data to date contain spatial variations in seismic-wave speed; however, in many cases these data sets do not by themselves allow a non-unique interpretation. Joint interpretation of seismic attenuation and velocity models can improve upon the interpretations based only on velocity and provide important constraints on the temperature, composition, melt content, and volatile content of the mantle. The surface wave amplitudes that constrain upper-mantle attenuation are sensitive to factors in addition to attenuation, including the earthquake source excitation, focusing and defocusing by elastic structure, and local site amplification. Because of the difficulty of isolating attenuation from these other factors, little is known about the attenuation structure of the North American upper mantle. In this study, Rayleigh wave traveltime and amplitude in the period range 25-100 s are measured using an interstation cross-correlation technique, which takes advantage of waveform similarity at nearby stations. Several estimates of Rayleigh wave attenuation and site amplification are generated at each period, using different approaches to separate the effects of attenuation and local site amplification on amplitude. It is assumed that focusing and defocusing effects can be described by the Laplacian of the traveltime field. All approaches identify the same large-scale patterns in attenuation, including areas where the attenuation values are likely contaminated by unmodelled focusing and defocusing effects. Regionally averaged attenuation maps are constructed after removal of the contaminated attenuation values, and the variations in intrinsic shear attenuation that are suggested by these Rayleigh wave attenuation maps are explored.

  19. Metformin attenuates pressure overload-induced cardiac hypertrophy via AMPK activation

    Institute of Scientific and Technical Information of China (English)

    Yong-nan FU; Han XIAO; Xiao-wei MA; Sheng-yang JIANG; Ming XU; You-yi ZHANG

    2011-01-01

    Aim: To identify the role of metformin in cardiac hypertrophy and investigate the possible mechanism underlying this effect.Methods: Wild type and AMPKα2 knockout (AMPKα2-/-) littermates were subjected to left ventricular pressure overload caused by evaluated using echocardiography and anatomic and histological methods. The antihypertrophic mechanism of metformin was analyzed using Western blotting.Results: Metformin significantly attenuated cardiac hypertrophy induced by pressure overload in wild type mice, but the antihypertrophic actions of metformin were ablated in AMPKx2-/- mice. Furthermore, metformin suppressed the phosphorylation of Akt/protein kinase B (AKT) and mammalian target of rapamycin (mTOR) in response to pressure overload in wild type mice, but not in AMPKα2-/-mice.Conclusion: Long-term administration of metformin may attenuate cardiac hypertrophy induced by pressure overload in nondiabetic mice, and this attenuation is highly dependent on AMPK activation. These findings may provide a potential therapy for patients at risk of developing pathological cardiac hypertrophy.

  20. Changes of Left Ventricular Geometry Shape and Left Ventricular Regional Function in Patients With Dilated Cardiomyopathy

    Institute of Scientific and Technical Information of China (English)

    Liang-yu WANG; Ming-xing XIE; Qing-bo LI; Ping CHEN; Zhi-xiong CAI; Zhi-dan ZHU

    2009-01-01

    Objectives To assess the left ventricle regional systolic and diastolic function, left ventricle geometry and left venti-tie sphericity indexes in patients with dilated cardiomyopathy (DCM) by quantitative tissue velocity imaging (QTVI). Methods Thirty normal subjects and 52 DCM patients underwent QTVI and colour Doppler flow imaging study in or-der to measure the left ventricular regional function along left ventricle apical long-axis view and the left ventricle geom-etry. Peak tissue velocities of left venticle regional muscular tissue during systole (Vs), systolic acceleration (a), ear-ly diastole(Ve) and left atrium contraction(Va) along left venticle apical long axis view were measured. The indexes of left ventdcular regional systolic and diastolic function were mearsured at the same time. The left ventricle geometry shape was reflected from the systolic and diastolic sphericity index (Sis and Sid), the left ventricular ejection fraction (LVEF) and D wave/A wave (PVd/Pva) of pulmonary veins flowing spectrum reflected the global left ventricular systolic and diastolic function. The Vs, Ve, Va, a, PVd/Pva ratio, LVEF, Sis, Sid and their correlations between normal subjects and patients with DCM were compared and analyzed. Results Vs, Ve, Va, a, PVd/Pva, Sis and Sid in patients with DCM were lower than those in normal persons. There were significant relations between Sis and a (r=0.6142, P<0.05), Ve/Va and Sid (r=0.6271, P<0.05). Conclusions QTVI offer a newer method which has a higher sensitivity and accuracy in evaluating the left venticle regional systolic and diastolic function in DCM patients. There was significant relation between regional cardiac function and left venticle sphericity.

  1. SEISMIC ATTENUATION FOR RESERVOIR CHARACTERIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Joel Walls; M.T. Taner; Naum Derzhi; Gary Mavko; Jack Dvorkin

    2003-12-01

    We have developed and tested technology for a new type of direct hydrocarbon detection. The method uses inelastic rock properties to greatly enhance the sensitivity of surface seismic methods to the presence of oil and gas saturation. These methods include use of energy absorption, dispersion, and attenuation (Q) along with traditional seismic attributes like velocity, impedance, and AVO. Our approach is to combine three elements: (1) a synthesis of the latest rock physics understanding of how rock inelasticity is related to rock type, pore fluid types, and pore microstructure, (2) synthetic seismic modeling that will help identify the relative contributions of scattering and intrinsic inelasticity to apparent Q attributes, and (3) robust algorithms that extract relative wave attenuation attributes from seismic data. This project provides: (1) Additional petrophysical insight from acquired data; (2) Increased understanding of rock and fluid properties; (3) New techniques to measure reservoir properties that are not currently available; and (4) Provide tools to more accurately describe the reservoir and predict oil location and volumes. These methodologies will improve the industry's ability to predict and quantify oil and gas saturation distribution, and to apply this information through geologic models to enhance reservoir simulation. We have applied for two separate patents relating to work that was completed as part of this project.

  2. Magnetoelectric Composite Based Microwave Attenuator

    Science.gov (United States)

    Tatarenko, A. S.; Srinivasan, G.

    2005-03-01

    Ferrite-ferroelectric composites are magnetoelectric (ME) due to their response to elastic and electromagnetic force fields. The ME composites are characterized by tensor permittivity, permeability and ME susceptibility. The unique combination of magnetic, electrical, and ME interactions, therefore, opens up the possibility of electric field tunable ferromagnetic resonance (FMR) based devices [1]. Here we discuss an ME attenuator operating at 9.3 GHz based on FMR in a layered sample consisting of lead magnesium niobate-lead titanate bonded to yttrium iron garnet (YIG) film on a gadolinium gallium garnet substrate. Electrical tuning is realized with the application of a control voltage due to ME effect; the shift is 0-15 Oe as E is increased from 0 to 3 kV/cm. If the attenuator is operated at FMR, the corresponding insertion loss will range from 25 dB to 2 dB. 1. S. Shastry and G. Srinivasan, M.I. Bichurin, V.M. Petrov, A.S. Tatarenko. Phys. Rev. B, 70 064416 (2004). - supported by grants the grants from the National Science Foundation (DMR-0302254), from Russian Ministry of Education (Å02-3.4-278) and from Universities of Russia Foundation (UNR 01.01.026).

  3. Social aspects of left-handedness

    Directory of Open Access Journals (Sweden)

    Belojević Goran

    2010-01-01

    Full Text Available Throughout human history left-handedness has been considered as sinful. It has been associated with the devil, weakness, female gender, unhealthiness, evil, something that has to be turned to a “good” - right side by force. Left-handedness is being more and more acceptable at rational level, but in everyday life it is still considered to be unusual if someone writes with the left hand. Lessening of the number of lefthanders is associated with ageing. There are about 13% lefthanders among people in twenties and less than 1% lefthanders among those in eighties. This finding may be explaned with more pronounced socio-cultural pressure on left-handed people in the past, compared to nowadays. On the other hand, this may also support the hypothesis about a reduced life span of lefthanded people. With cross-exercising of left-handedness, certain typical characteristics and behavioral patterns appear in these people. This was a sort of provoked behavior and an attack on the integrity of an emotional attitude toward oneself. Stuttering may also appear as a consequence of unsuccessful cross-exercising of left-handedness. The hypothesis about left-handedness as an advantage is supported with the reports about relatively more lefthanders in some specific groups such as: mathematicians, sculptors, architects, painters, musicians, actors, tennis players, as well as famous army commanders and rulers.

  4. Effects of Tribuli Saponins on Left Ventricular Remodeling after Acute Myocardial Infarction in Rats with Hyperlipidemia

    Institute of Scientific and Technical Information of China (English)

    GUO Yan; YIN Hui-jun; SHI Da-zhuo; CHEN Ke-ji

    2005-01-01

    Objective: To observe the effect of Tribuli saponins (TS) on left ventricularremodeling after acute myocardial infarction(AMI) in rats with hyperlipemia. Methods: A composite model of myocardial infarction and hyperlipemia was established and treated with TS to observe its effect on cardiac structure and function by echocardiography. Results: (1) Cardiac function: As compared with the model group, the fractional shortening (FS) and ejection fraction (EF) got increased, and the left ventricular end diastolic volume (LVEDV) and systolic volume (LVESV) got lower in the groups treated with high dose TS and simvastatin ( P<0.05 or P<0.01 ), but difference between the two treated groups was insignificant. (2) Cardiac structure: As compared with the model group, the left ventricular dimension end diastole (LVDd) and systole (LVDs) in the groups treated with high dose TS and simvastatin got lower ( P<0.05 or P<0.01 ). No treatment showed any effect on the thickness of ventricular wall. (3)Ventricular weight index: Both high dose TS and simvastatin could decrease the left ventricular weight index (LVWI) ( P<0.05). Conclusion: TS could attenuate the left ventricular remodeling after acute myocardial infarction to certain extent, and improve cardiac function in the early phase after AMI, thus playing an important role in controlling morbidity and mortality of cardiac events and long-term prognosis.

  5. Engaging Enemies: Hayek and the left

    OpenAIRE

    Griffiths, Simon

    2014-01-01

    Friedrich Hayek is a founding figure of the neo-liberalism that flourished in the 1980s; his work influenced policy on the right and was at odds with contemporary socialism. So how did the left come to rethink Hayek’s work? And is that significant to today’s post-crisis politics? Engaging Enemies thoroughly examines the response of the British left to the rise of Hayek’s pro-market theory. It explores the importance of attempts by the British left to rethink Hayek, and even to co-opt elem...

  6. Anomalous Feeding of the Left Upper Lobe.

    Science.gov (United States)

    Hazzard, Christopher; Itagaki, Shinobu; Lajam, Fouad; Flores, Raja M

    2016-09-01

    We report the case of a 53-year-old woman who presented with massive hemoptysis. Computed tomographic angiography revealed an anomalous vessel arising from the abdominal aorta, coursing anteriorly and through the diaphragm, and feeding the left upper lobe. At operation the vessel was found to anastomose to the left upper lobe lingula, which contained multiple vascular abnormalities and arteriovenous fistulas. The vessel was ligated, and the affected portion of the left upper lobe was resected. Anomalous systemic arterial supply of an upper lobe is an especially rare form of a Pryce type 1 abnormality. Recognition of these unusual anatomic variants is crucial to successful treatment and avoidance of adverse events.

  7. Left atrial systolic force in hypertensive patients with left ventricular hypertrophy: the LIFE study

    DEFF Research Database (Denmark)

    Chinali, M.; Simone, G. de; Wachtell, K.;

    2008-01-01

    In hypertensive patients without prevalent cardiovascular disease, enhanced left atrial systolic force is associated with left ventricular hypertrophy and increased preload. It also predicts cardiovascular events in a population with high prevalence of obesity. Relations between left atrial...... systolic force and left ventricular geometry and function have not been investigated in high-risk hypertrophic hypertensive patients. Participants in the Losartan Intervention For Endpoint reduction in hypertension echocardiography substudy without prevalent cardiovascular disease or atrial fibrillation (n......, transmitral peak E velocities and peak A velocities; and lower E/A ratio (all P hypertensive patients with greater left ventricular mass and prevalence of left ventricular hypertrophy, but normal left ventricular chamber systolic function with increased...

  8. Ultrasound fields in an attenuating medium

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt; Gandhi,, D; O'Brien,, W.D., Jr.

    1993-01-01

    Ultrasound fields propagating in tissue will undergo changes in shape not only due to diffraction, but also due to the frequency dependent attenuation. Linear fields can be fairly well predicted for a non-attenuating medium like water by using the Tupholme-Stepanishen method for calculating...... it into a frequency dependent part and frequency independent part. The latter results in an attenuation factor that is multiplied onto the responses from the individual elements, and the frequency dependent part is handled by attenuating the basic one-dimensional pulse. The influence on ultrasound fields from...

  9. Applications of magnetic resonance imaging in the assessment of left ventricular dysfunction

    Energy Technology Data Exchange (ETDEWEB)

    Beacock, David John

    2002-07-01

    This thesis has described the use of Magnetic Resonance Imaging (MRI) in the investigation of left ventricular dimensions and systolic function. This has been performed in conditions of left ventricular dysfunction, in congestive cardiac failure and following anterior myocardial infarction. The reproducibility of measurements of left ventricular dimensions using MRI has been presented. Such measurements were shown to be reproducible between different MRI studies of normal volunteers and patients with congestive heart failure. Furthermore, measurements from different MRI studies obtained from two commercially different systems were reproducible for the same subject groups. Ventricular dimensions and systolic function was evaluated in adult normal volunteers of different ages. Although left ventricular volumes and mass remained unchanged, detailed studies of the systolic images revealed significant differences between the two age groups. Differences in left ventricular cavity volumes and mass between patients with congestive heart failure and age-matched normal volunteers were also investigated. Left ventricular volumes and myocardial mass were assessed in a group of patients following anterior myocardial infarction. End-systolic volume was significantly increased compared to age-matched volunteers, but no changes in end-diastolic volume or myocardial mass was observed. Serial re-evaluation of these patients revealed no other changes over the subsequent six months. All these patients were treated with optimal medical therapy (thrombolysis, aspirin, beta-blockade and angiotensin converting enzyme inhibition). Thus, the use of this therapy may attenuate the process of left ventricular remodelling. Regional wall thickness was measured in the post-infarct patients. Wall thickening was significantly reduced both in the infarcted regions and in myocardium remote to the infarction. In contrast to previous echocardiographic studies, no 'hypercontractility' was

  10. Ultrasonic attenuation in cuprate superconductors

    Indian Academy of Sciences (India)

    T Gupta; D M Gaitonde

    2002-05-01

    We calculate the longitudinal ultrasonic attenuation rate (UAR) in clean d-wave superconductors in the Meissner and the mixed phases. In the Meissner phase we calculate the contribution of previously ignored processes involving the excitation of a pair of quasi-holes or quasi-particles. There is a contribution ∝ in the regime B ≪ F ≪ 0 and a contribution ∝ 1/ in the regime F ≪ B ≪ 0. We find that these contributions to the UAR are large and cannot be ignored. In the mixed phase, using a semi-classical description, we calculate the electronic quasi-particle contribution to the UAR which at very low , has a independent term proportional to $\\sqrt{H}$.

  11. Attenuation characteristics of gypsum wallboard

    International Nuclear Information System (INIS)

    Increased cost of lead is promoting enhanced usage of common building materials for shielding in diagnostic medical and dental facilities where only a few half-value layers (HVLs) are needed. Attenuation of primary beam X-ray photons in gypsum wallboard as a function of kVp, filtration, and wallboard thickness have been measured. Findings, obtained using a Victoreen 555 with an 0.1 DAS probe in poor geometry, are substantially in agreement with the sparse data in the literature but extend to thicker wall configurations and different kVp and filtration parameters. These findings are of value in maximizing the benefit/cost ratio for diagnostic shielding, and strengthen the conviction that, where used for shielding purposes, common building materials must be installed carefully and HVL-depth dependence considered thoroughly. (author)

  12. Transmission Losses in Left-handed Materials

    OpenAIRE

    Markos, P; Rousochatzakis, I.; Soukoulis, C. M.

    2002-01-01

    We numerically analyze the origin of the transmission losses in left-handed structures. Our data confirms that left handed structures can have very good transmission properties, in spite of the expectable dispersion of their effective permeability and refraction index. The large permittivity of the metallic components improves the transmission. High losses, observed in recent experiments, could be explained by the absorption of the dielectric board.

  13. Laparoscopic vs open left hepatectomy for hepatolithiasis

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM: To explore the feasibility and therapeutic effect of total laparoscopic left hepatectomy (LLH) for hepatolithiasis. METHODS: From June 2006 to October 2009, 61 consecutive patients with hepatolithiasis who met the inclusion criteria for LLH were treated in our institute. Of the 61 patients with hepatolithiasis, 28 underwent LLH (LLH group) and 33 underwent open left hepatectomy (OLH group). Clinical data including operation time, intraoperative blood loss, postoperative complication rate, postoperative...

  14. White matter fiber degradation attenuates hemispheric asymmetry when integrating visuomotor information.

    Science.gov (United States)

    Schulte, Tilman; Müller-Oehring, Eva M; Rohlfing, Torsten; Pfefferbaum, Adolf; Sullivan, Edith V

    2010-09-01

    Degradation of white matter fibers can affect the transmission of signals in brain circuits that normally enable integration of highly lateralized visual and motor processes. Here, we used diffusion tensor imaging tractography in combination with functional magnetic resonance imaging to examine the specific contributions of interhemispheric and intrahemispheric white matter fibers to functional measures of hemispheric transfer and parallel information processing using bilateral and unilateral left and right visual field stimulation in normal and compromised systems. In healthy adults, a greater degree of bilateral processing advantage with the left (nondominant) hand correlated with higher integrity of callosal fibers connecting occipital cortices, whereas less unilateral processing advantage with the right hand correlated with higher integrity of left-hemispheric posterior cingulate fibers. In contrast, alcoholics who have compromised callosal integrity showed less bilateral processing advantage than controls when responding with the left hand and greater unilateral processing advantage when responding with the right hand. We also found degraded left posterior cingulate and posterior callosal fibers in chronic alcoholics, which is consistent with functional imaging results of less left posterior cingulate and extrastriate cortex activation in alcoholics than controls when processing bilateral compared with unilateral visual field stimulation. Together, our results demonstrated that interhemispheric and intrahemispheric white matter fiber pathways mediate visuomotor integration asymmetrically and that subtle white matter fiber degradation in alcoholism attenuated the normal pattern of hemispheric asymmetry, which may have ramifications for the efficiency of visual information processing and fast response execution.

  15. Left △-Product Structure of Left C-Wrpp Semigroups%左G-Wrpp半群的左△-积

    Institute of Scientific and Technical Information of China (English)

    张晓敏

    2009-01-01

    We study another structure of so-called left C-wrpp semigroups.In particular,the concept of left △-product is extended and enriched.The aim of this paper is to give a construction of left C-wrpp semigroups by a left regular band and a strong semilattice of left-R cancellative monoids.Properties of left C-wrpp semigroups endowed with left △-products are particularly investigated.

  16. Total Arterial Revascularisation in Left Ventricular Dysfunction

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The feasibility and safety of total arterial coronary revascularization with 2 arterial conduits in patients with impaired left ventricular function was evaluated. Data were prospectively collected on all patients with multiple vessel disease and moderately or severely impaired left ventricular function, who underwent coronary surgery with the intention of total arterial revascularization with 2 conduits between March 1995 and August 2002. One hundred and seventy-nine patients were included in the study. Acute coronary insufficiency was present in 3 patients and 43 had unstable angina. Severe left ventricular impairment was present in 29 patients. There were 17 redo operations including 3 redo-redo procedures. Eighty-two percent of patients had a Y graft configuration from the left internal mammary artery (right internal mammary artery 40. 8 %, radial artery 33.5 %,other 7.8 % ). The perioperative mortality was 2.2 %, myocardial infarction 1.7 % and stroke 0. 6 %.Total arterial revascularization in patients with ischaemic left ventricular dysfunction can be safely performed with 2 arterial conduits. The radial artery provides conduit length greater than the right internal mammary artery and allows full revascularization despite left ventricular dilatation.

  17. Lung attenuation measurements in healthy young adults.

    NARCIS (Netherlands)

    Smit, H.J.M.; Golding, R.P.; Schramel, F.M.N.H.; Devillé, W.L.; Manoliu, R.A.; Postmus, P.E.

    2003-01-01

    Background: High-resolution computed tomography (HRCT) attenuation measurements may be more sensitive in finding early emphysematous changes in relatively young subjects than lung function measurements. Objectives: To define lung attenuation parameters in smokers and never-smokers. Methods: A prospe

  18. Simple parameterization of nuclear attenuation data

    CERN Document Server

    Akopov, N; Akopov, Z

    2007-01-01

    Based on the nuclear attenuation data obtained by the HERMES experiment on nitrogen and krypton nuclei, it is shown that the nuclear attenuation $R_M^{h}$ can be parametrised in a form of a linear polynomial $P_1=a_{11}$ + $\\tau a_{12}$, where $\\tau$ is the formation time, which depends on the energy of the virtual photon $\

  19. Precision Model for Microwave Rotary Vane Attenuator

    DEFF Research Database (Denmark)

    Guldbrandsen, Tom

    1979-01-01

    A model for a rotary vane attenuator is developed to describe the attenuator reflection and transmission coefficients in detail. All the parameters of the model can be measured in situ, i.e., without diassembling any part. The tranmission errors caused by internal reflections are calculated from ...

  20. Verapamil and angiotensin-converting enzyme inhibitors in patients with coronary artery disease and reduced left ventricular ejection fraction

    DEFF Research Database (Denmark)

    Hansen, J F; Tingsted, L; Rasmussen, Verner;

    1996-01-01

    Verapamil is effective as antianginal medication but contraindicated in patients with congestive heart failure. Angiotensin-converting enzyme (ACE) inhibitors improve survival in patients with congestive heart failure but have limited effect on patients with angina pectoris. No studies have been.......4 to 2.5 +/- 0.6 (p attacks were both significantly reduced after 3 months of treatment. These findings support the hypothesis that the combination of verapamil and trandolapril is useful in patients with attenuated left ventricular function...

  1. Inhibitory transcranial magnetic theta burst stimulation attenuates prefrontal cortex oxygenation.

    Science.gov (United States)

    Tupak, Sara V; Dresler, Thomas; Badewien, Meike; Hahn, Tim; Ernst, Lena H; Herrmann, Martin J; Deckert, Jürgen; Ehlis, Ann-Christine; Fallgatter, Andreas J

    2013-01-01

    Recent studies highlighted the great potential of newly established theta burst stimulation (TBS) protocols for non-invasive human brain stimulation studies using transcranial magnetic stimulation (TMS). While intermittent TBS over the primary motor cortex was found to potentiate motor evoked potentials, continuous TBS led to profound attenuations. Although numerous studies investigated the impact of TBS on motor cortex function, yet, only few imaging studies focused on its effects in other brain areas. Particularly for the prefrontal cortex, it is unclear whether TBS has similar effects compared to application over motor areas. In the current study continuous TBS was applied to either the left or right dorsolateral prefrontal cortex in a sample of healthy subjects. Changes in prefrontal oxygenation were measured during an emotional Stroop task by means of functional multi-channel near-infrared spectroscopy (fNIRS) before and after stimulation. Results showed bilaterally decreased prefrontal oxygenation following inhibitory stimulation of the left prefrontal cortex but no behavioral effect. No such alterations were observed following right-hemispheric or sham stimulation. The results of the current study are in line with earlier findings and additionally demonstrate that also prefrontal oxygenation can be impaired by continuous TBS.

  2. Left ventricular non-compaction cardiomyopathy and left ventricular assist device: a word of caution

    OpenAIRE

    Kornberger, A.; Stock, U. A.; Risteski, P.; Beiras Fernandez, A.

    2016-01-01

    Background In patients with left ventricular non-compaction (LVNC), implantation of a left ventricular assist device (LVAD) may be performed as a bridge to transplantation. In this respect, the particular characteristics of the left ventricular myocardium may represent a challenge. Case presentation We report a patient with LVNC who required urgent heart transplantation for inflow cannula obstruction nine months after receiving a LVAD. LVAD parameters, echocardiography and examination of the ...

  3. Composite Right- and Left-Handed Traveling-Wave Field-Effect Transistors

    Directory of Open Access Journals (Sweden)

    Koichi Narahara

    2012-01-01

    Full Text Available We introduce a composite right- and left-handed travelling-wave field-effect transistor (CRLH TWFET for developing large-scale platform to support left-handed waves. The device represents two electromagnetically coupled CRLH transmission lines by capacitance and FET transconductance. Owing to the couplings, two different modes can support waves in CRLH TWFETs. It was experimentally established that waves supported by one of the modes were amplified, while those supported by the other mode were significantly attenuated. To quantify the wave propagation in CRLH TWFETs, we developed a numerical model based on the transmission line theory that well simulated measured results. This paper discusses the results of numerical calculations that validate the design criteria of CRLH TWFETs.

  4. Left behind radiological investigations: An inherent problem

    Directory of Open Access Journals (Sweden)

    Giridhar A Govindswamy

    2011-01-01

    Full Text Available Objectives: To assess the number of investigations left behind by patients in radiology department, their cost, and the possible methods of reducing the problem. Materials and Methods: A total of 1424 radiographs, 160 computed tomography (CT scans, 300 ultrasonography (USG reports, and 46 Doppler reports were left behind by patients in one financial year. The total cost of these left behind investigations was calculated and the reports were categorized into normal and abnormal for each modality. Results: Of the radiographs left behind 658 were abnormal, with 211 among these being radiographs of postoperative patients. Thirty-seven percent of CT scans had positive findings. Sixty-eight percent of USG reports had positive findings while 46% of Doppler reports were abnormal. Conclusion: We believe that the cost and number of these left behind investigations over a period of time would definitely be significant for the health care system in a developing country. It is time to think of the possible reasons and methods for containing this problem.

  5. What is Beyond Right/Left?

    DEFF Research Database (Denmark)

    Dyrberg, Torben Bech

    2009-01-01

    The article looks at New Labour's move beyond right/left in the mid/late 1990s, which is an occasion to spell out the nature of right/left and what it means for democracy. In contrast to both defenders and critics of this move I argue in the first part that right/left is not an empty label bound up...... with the cleavage-lines of industrial society, but that it is an orientational metaphor which is articulated with others-in/out, up/down and front/back-and that we are in the process of moving beyond the industrial society right/left prototype. The second part looks at where New Labour is heading when moving beyond...... right/left. I argue that the new hegemonic orientation is that of front/back, which designs political renewal as a response to the social changes cutting across the outdated lines of contestation of partisan politics. The democratic problem of this move lies in squeezing politics between technocratic...

  6. Live attenuated intranasal influenza vaccine.

    Science.gov (United States)

    Esposito, Susanna; Montinaro, Valentina; Groppali, Elena; Tenconi, Rossana; Semino, Margherita; Principi, Nicola

    2012-01-01

    Annual vaccination is the most effective means of preventing and controlling influenza epidemics, and the traditional trivalent inactivated vaccine (TIV) is by far the most widely used. Unfortunately, it has a number of limitations, the most important of which is its poor immunogenicity in younger children and the elderly, the populations at greatest risk of severe influenza. Live attenuated influenza vaccine (LAIV) has characteristics that can overcome some of these limitations. It does not have to be injected because it is administered intranasally. It is very effective in children and adolescents, among whom it prevents significantly more cases of influenza than the traditional TIV. However, its efficacy in adults has not been adequately documented, which is why it has not been licensed for use by adults by the European health authorities. LAIV is safe and well tolerated by children aged > 2 y and adults, but some concerns arisen regarding its safety in younger children and subjects with previous asthma or with recurrent wheezing. Further studies are needed to solve these problems and to evaluate the possible role of LAIV in the annual vaccination of the general population.

  7. Beta attenuation transmission system (BATS)

    Energy Technology Data Exchange (ETDEWEB)

    Hagan, R.C.; Fullbright, H.J.

    1977-01-01

    The beta attenuation transmission system (BATS) is an automated radiation gauge designed for quantitative measurement of component thickness in explosive detonators. The BATS was designed and built by Group M-1, the Nondestructive Testing Group, of the Los Alamos Scientific Laboratory to measure the areal thickness, in mg/cm/sup 2/, of a cylinder of high explosive (HE) enclosed within a plastic holder. The problem is to determine the density of the HE. A /sup 90/Sr source is collimated by a 0.25 x 1.59-mm slit, and the transmitted beta-particle flux is detected by a plastic scintillator, coupled to a photomultiplier tube. The detonator is transported through the radiation beam by a leadscrew, ballnut, stepping-motor combination. Continuous analog position data are available, derived from the output from a linear-actuated potentiometer attached to the scanner. A linear electrometer amplifies the detected signal, which is then integrated for a preselected time, to obtain the desired statistical accuracy. A microprocessor (..mu..P) is used to control the scanner position and to make the data readings at the assigned positions. The data are stored, and, at the completion of the scan, are processed into the desired format. The final answer is displayed to the operator or output to a peripheral device for permanent record. The characteristics of the radiation source, the collimator, the signal detection and conditioning, and the final results are described in detail. The scanner and the microprocessor control system are briefly outlined.

  8. Attenuation of diacylglycerol second messengers

    Energy Technology Data Exchange (ETDEWEB)

    Bishop, W.R.; Ganong, B.R.; Bell, R.M.

    1986-05-01

    Diacylglycerol(DAG) derived from phosphatidylinositol activates protein kinase C in agonist-stimulated cells. At least two pathways may contribute to the attenuation of the DAG signal: (1) phosphorylation to phosphatidic acid(PA) by DAG kinase(DGK), and (2) deacylation by DAG and monoacylglycerol lipases. A number of DAG analogs were tested as substrates and inhibitors of partially purified pig brain DGK. Two analogs were potent inhibitors in vitro, 1-monooleoylglycerol(MOG,K/sub I/ = 91 ..mu..M) and diotanoylethyleneglycol (diC/sub 8/EG, K/sub I/ = 58 ..mu..M). These compounds were tested in human platelets. DiC/sub 8/EG inhibited (70 - 100%) (/sup 32/P/sub i/) incorporation into PA in thrombin-stimulated platelets. Under these conditions the DAG signal was somewhat long-lived but was still metabolized, presumably by the lipase pathway. MOG treatment elevated DAG levels up to 4-fold in unstimulated platelets. The DAG formed was in a pool where it did not activate protein kinase C. Thrombin-stimulation of MOG-treated platelets resulted in DAG levels 10-fold higher than control platelets. This appears to be due to the inability of these platelets to metabolize agonist-linked DAG via the lipase pathway. The development of specific inhibitors of DAG kinase and DAG lipase, in conjunction with mass quantification of DAG levels as used here, will provide further insights into the regulation of DAG second messengers.

  9. Left-Wing Extremism: The Current Threat

    Energy Technology Data Exchange (ETDEWEB)

    Karl A. Seger

    2001-04-30

    Left-wing extremism is ''alive and well'' both in the US and internationally. Although the current domestic terrorist threat within the U. S. is focused on right-wing extremists, left-wing extremists are also active and have several objectives. Leftist extremists also pose an espionage threat to U.S. interests. While the threat to the U.S. government from leftist extremists has decreased in the past decade, it has not disappeared. There are individuals and organizations within the U.S. who maintain the same ideology that resulted in the growth of left-wing terrorism in this country in the 1970s and 1980s. Some of the leaders from that era are still communicating from Cuba with their followers in the U.S., and new leaders and groups are emerging.

  10. Calculation of vehicular load-induced plastic deformation of soft subsoil%车辆荷载作用下软土地基塑性变形的计算

    Institute of Scientific and Technical Information of China (English)

    申昊; 唐晓武; 牛犇; 刘续

    2013-01-01

    对于低路堤公路,合理地预测车辆荷载引起的地基塑性累积变形对于低路堤公路的设计有着重要的意义。从机制上讲,可将地基的塑性应变分为塑性体积应变和塑性剪切应变。其中对于塑性体积应变,提出采用不排水条件下的残余孔压模型与一维固结理论相耦合进行计算;对于塑性剪切应变,考虑了塑性体积应变引起的土体硬化,提出了修正的塑性剪切应变计算模型。然后基于所提模型,对萧山黏土的不排水与排水条件下的动三轴试验进行模拟,初步验证了所提模型的有效性。对于实际工程问题,首先运用数值的方法求得车辆荷载在地基中引起的附加应力,然后运用所提模型计算各土层的塑性应变,再结合分层总和的方法求得地基的累积塑性变形。以日本佐贺机场1号测点为例,说明了模型在工程边值问题中的有效性。%For a low embankment road, the reasonable prediction of vehicular load-induced plastic deformation plays an important role in the road design. According to the mechanism of vehicular load-induced plastic strain, the plastic strain comprises two parts:plastic volumetric strain and plastic shear strain. In the calculation of plastic volumetric strain, the dissipation equation with a source term, which couples Terzaghi’s consolidation theory with the experimentally-achieved cumulative pore pressure model under undrained condition is adopted. While in the calculation of plastic shear strain, the hardening factor of plastic volumetric strain is taken into consideration. The validity of the model is verified by the dynamic triaxial test results of saturated clay under undrained and drained condition. For practical problems, the vehicular load-induced stress is calculated by the numerical method firstly;then the plastic strain can be calculated by the proposed model. Finally, the plastic deformation is obtained by the layer

  11. Clustered survival data with left-truncation

    DEFF Research Database (Denmark)

    Eriksson, Frank; Martinussen, Torben; Scheike, Thomas H.

    2015-01-01

    Left-truncation occurs frequently in survival studies, and it is well known how to deal with this for univariate survival times. However, there are few results on how to estimate dependence parameters and regression effects in semiparametric models for clustered survival data with delayed entry....... Surprisingly, existing methods only deal with special cases. In this paper, we clarify different kinds of left-truncation and suggest estimators for semiparametric survival models under specific truncation schemes. The large-sample properties of the estimators are established. Small-sample properties...

  12. Lone, Mobile Left Atrial Hydatid Cyst

    Science.gov (United States)

    Ugurlu, Mehmet; Baktir, Ahmet Oguz; Tekin, Ali Ihsan; Tok, Ahmet; Yagmur, Bayram

    2016-01-01

    Echinococcosis is endemic in various regions of Turkey. Cardiac involvement in echinococcosis is rare, and lone cardiac hydatid cysts are even more unusual. Because cardiac hydatid disease can be fatal, even asymptomatic patients are optimally referred for surgical treatment. We present a rare case of a lone, primary, mobile hydatid cyst in the left atrium of a 62-year-old woman. The cyst caused dyspnea from left ventricular inflow obstruction. In addition to reporting the patient's fatal case, we discuss cardiac hydatid cysts in terms of the scant medical literature. PMID:27303247

  13. Left paraduodenal hernias; Hernias paraduodenales izquierdas

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Negrete, L.; Garcia-Lozano, J.; Sanchez, J. L.; Tejeiro, A.; Sala, J. [Hospital Valle del Nalon. Riano-Sama. Asturias (Spain)

    2002-07-01

    We report two cases of left paraduodenal internal hernias located in the fossa of Landzert that were diagnosed by CT. Internal hernias are an infrequent cause of acute abdomen, due to the intestinal sub occlusion they produce. Left paraduodenal hernias are responsible for about 50% of internal hernias. CT makes it possible to demonstrate the group of herniated loops between the stomach, fourth segment of the duodenum, descending colon, and tail of the pancreas. The identification of the loops in an atypical position together with displaced blood vessels (mesenteric vessels) and colon gives concerns on them a typical radiological semiology that makes them easily identifiable. (Author) 9 refs.

  14. Echocardiographic study of left atrial myxoma

    Directory of Open Access Journals (Sweden)

    Dalal J

    1979-01-01

    Full Text Available Four cases of left atrial myxoma were diagnosed pre-operatively by echocardiography. All cases showed characteristic echocardio-graphic features of variegated shadows behind the mitral valve in diastole and within the left atrium in systole. In two cases the my-xomas were surgically removed and confirmed on histology. In one case the post-operative echocardiogram showed complete dis-appearance of the abnormal shadows. Echocardiography is the most reliable method today for the diagnosis of a myxoma.

  15. Left common basal pyramid torsion following left upper lobectomy/segmentectomy.

    Science.gov (United States)

    Wang, Wei-Li; Cheng, Yen-Po; Cheng, Ching-Yuan; Wang, Bing-Yen

    2015-05-01

    Lobar or segmental lung torsion is a severe complication of lung resection. To the best of our knowledge, common basal pyramid torsion has never been reported. We describe a case of left basal pyramid torsion after left upper lobectomy and superior segmentectomy, which was successfully treated by thoracoscopic surgery.

  16. Left ventricular assist device implantation via left thoracotomy: alternative to repeat sternotomy.

    Science.gov (United States)

    Pierson, Richard N; Howser, Renee; Donaldson, Terri; Merrill, Walter H; Dignan, Rebecca J; Drinkwater, Davis C; Christian, Karla G; Butler, Javed; Chomsky, Don; Wilson, John R; Clark, Rick; Davis, Stacy F

    2002-03-01

    Repeat sternotomy for left ventricular assist device insertion may result in injury to the right heart or patent coronary grafts, complicating intraoperative and postoperative management. In 4 critically ill patients, left thoracotomy was used as an alternative to repeat sternotomy. Anastomosis of the outflow conduit to the descending thoracic aorta provided satisfactory hemodynamic support.

  17. Graphene-based Electronically Tuneable Microstrip Attenuator

    Directory of Open Access Journals (Sweden)

    L. Pierantoni

    2014-06-01

    Full Text Available This paper presents the design of a graphene- based electronically tuneable microstrip attenuator operating at a frequency of 5 GHz. The use of graphene as a variable resistor is discussed and the modelling of its electromagnetic properties at microwave frequencies is fully addressed. The design of the graphene-based attenuator is described. The structure integrates a patch of graphene, whose characteristics can range from being a fairly good conductor to a highly lossy material, depending on the applied voltage. By applying the proper voltage through two high-impedance bias lines, the surface resistivity of graphene can be modified, thereby changing the insertion loss of the microstrip attenuator.

  18. Postoperative normalization of left ventricular noncompaction and new echocardiographic signs in aorta to left ventricular tunnel.

    Science.gov (United States)

    Malakan Rad, Elaheh; Zeinaloo, Ali Akbar

    2013-04-01

    We report postoperative normalization of left ventricular noncompaction in a neonate undergoing successful neonatal surgery for type II aorta to left ventricular tunnel (ALVT) associated with a large patent ductus arteriosus, floppy and extremely redundant anterior mitral leaflet, right coronary artery arising directly from the tunnel, and severe left ventricular noncompaction. We also described 2 novel echocardiographic findings in ALVT including "triple wavy line sign" on M-mode echocardiography which disappeared 1 month after operation and "abnormally increased left ventricular posterior wall motion" on M-mode of standard parasternal long-axis view on color tissue Doppler imaging (TDI) that also normalized postoperatively. We showed that proper definition of endocardial border is extremely important in strain and strain rate imaging in the context of left ventricular noncompaction. Preoperative longitudinal strain and strain rate were significantly decreased in comparison to radial strain and strain rate. Circumferential strain and strain rate were normal. PMID:23346986

  19. Left ventricular outflow obstruction and necrotizing enterocolitis

    Energy Technology Data Exchange (ETDEWEB)

    Allen, H.A.; Haney, P.J.

    1984-02-01

    Two neonates had unusually rapid development of necrotizing enterocolitis within 24 hours of birth. Both patients had decreased systemic perfusion secondary to aortic atresia. Onset of either clinical or radiographic manifestations of necrotizing enterocolitis in the first day of life should alert one to the possible presence of severe left ventricular outflow obstruction.

  20. Cerebrovascular complications of left ventricular assist devices

    NARCIS (Netherlands)

    Backes, Daan; van den Bergh, Walter M; van Duijn, Abram L; Lahpor, Jaap R; van Dijk, Diederik; Slooter, Arjen J C

    2012-01-01

    Left ventricular assist devices (LVADs) are increasingly being used as a bridge to heart transplantation or destination therapy. It is unclear which antithrombotic regimen should be used to reduce the risk of stroke. We systematically reviewed the literature on all types of antithrombotic regimens a

  1. Foreign Body in Left Main Bronchus.

    Science.gov (United States)

    Dhadke, Shubhangi V; Chaudhari, Amit L; Deshpande, Neelima S; Dhadke, Vithal N; Sangle, Shashikala A

    2015-07-01

    Tracheobronchial foreign body (TFB) aspiration is rare in adults, although incidence rates increases with advancing age. We report a case of foreign body in left main bronchus in an adult female who had no risk factor. She was successfully treated with removal of betel nuts by bronchoscopy. Unusual presentation and high index of suspicion can help in proper management. PMID:26731835

  2. BIVARIATE ESTIMATION WITH LEFT-TRUNCATED DATA

    Institute of Scientific and Technical Information of China (English)

    孙六全; 任浩波

    2001-01-01

    In this article we construct a kernel estimate of the probability function from bivariate data when a component is subject to random left-truncation. We establish consistency and asymptotic normality of the proposed estimator using a strong approximation result. Simulation studies show that the proposed procedure gives a good estimate of the true density function even when the sample size is moderate.

  3. Left ventricular hypertrophy : virtuous intentions, malign consequences

    NARCIS (Netherlands)

    Pokharel, S; Sharma, UC; Pinto, YM

    2003-01-01

    Left ventricular hypertrophy (LVH) is currently the focus of intense cardiovascular research, with the resultant rapid evolution of novel concepts relating to its exceedingly complex pathophysiology. In addition to the alterations in signal transduction and disturbances in Ca2+ homeostasis, there ar

  4. The Rings Characterized by Minimal Left Ideals

    Institute of Scientific and Technical Information of China (English)

    Jun Chao WEI

    2005-01-01

    We study these rings with every minimal left ideal being a projective, direct summand and a p-injective module, respectively. Some characterizations of these rings are given, and the relations among them are obtained. With these rings, we characterize semisimple rings. Finally, we introduce MC2 rings, and give some characterizations of MC2 rings.

  5. Heterotaxy syndrome: This is the left, right?

    OpenAIRE

    Lili Huang; Belinda J. Mitchell; Savvas Andronikou; Lockhat, Zarina I; Farhana Suleman

    2015-01-01

    Heterotaxy syndrome is a rare and complex disorder of the chest and abdominal organ arrangements, and presents a diagnostic challenge to the radiologist. This article describes the morphological characteristics of heterotaxy and situs abnormalities, in particular left and right atrial isomerism, and suggests an approach in evaluating the spectrum of abnormalities associated with heterotaxy syndromes, using appropriate imaging modalities.

  6. Topologically Left Invariant Means on Semigroup Algebras

    Indian Academy of Sciences (India)

    Ali Ghaffari

    2005-11-01

    Let $M(S)$ be the Banach algebra of all bounded regular Borel measures on a locally compact Hausdorff semitopological semigroup with variation norm and convolution as multiplication. We obtain necessary and sufficient conditions for $M(S)^∗$ to have a topologically left invariant mean.

  7. Support for radical left ideologies in Europe

    NARCIS (Netherlands)

    Visser, Mark; Lubbers, Marcel; Kraaykamp, Gerbert; Jaspers, Eva

    2014-01-01

    This article examines support for radical left ideologies in 32 European countries. It thus extends the relatively scant empirical research available in this field. The hypotheses tested are derived mainly from group-interest theory. Data are deployed from the 2002-2010 European Social Surveys (N=17

  8. Left-right model for dark matter

    CERN Document Server

    Dong, P V

    2016-01-01

    We argue that dark matter can automatically arise from a gauge theory that possesses a non-minimal left-right gauge symmetry, SU(3)_C \\otimes SU(M)_L \\otimes SU(N)_R \\otimes U(1)_X, for (M,N) = (2,3), (3,2), (3,3), \\cdots, and (5,5).

  9. Artificial, parallel, left-handed DNA helices.

    Science.gov (United States)

    Tian, Cheng; Zhang, Chuan; Li, Xiang; Li, Yingmei; Wang, Guansong; Mao, Chengde

    2012-12-19

    This communication reports an engineered DNA architecture. It contains multiple domains of half-turn-long, standard B-DNA duplexes. While each helical domain is right-handed and its two component strands are antiparallel, the global architecture is left-handed and the two component DNA strands are oriented parallel to each other.

  10. Attenuation layer for magnetostatic wave (MSW) absorbers

    Science.gov (United States)

    Glass, H. L.; Adkins, L. R.; Stearns, F. S.

    1984-09-01

    A new technique has been developed for the suppression of MSW end reflections which give rise to passband ripple. The basic idea is to provide a thin film of highly attenuating epitaxial material at the ends of a MSW delay line while preserving high quality YIG in the active region of the device. The GGG wafer preparation is a three step process which involves: (1) the growth of the attenuation layer, (2) the removal of this layer from the central region of the wafer and (3) the growth of high quality YIG on the remaining structure. Delay lines using the attenuation layer for end terminations have been evaluated experimentally and compared to devices utilizing other termination methods. The results indicate that the attenuation layer method produces ripple suppression characteristics which are the equal of those obtained with other termination techniques. The advantage of this new method lies in its suitability for large quantity fabrication requirements.

  11. Radiation-attenuated vaccine for lungworm disease

    International Nuclear Information System (INIS)

    The work done at the Indian Veternary Research Institute, Izatnagar, on the development of a vaccine for lungworm diseases is reported. Research work done includes: (1) studies on the epidemiology and the incidence of the lungworm infections, (ii) studies on the radiation-attenuated lungworm Dictyocaulus filaria vaccine, (iii) studies on other parasites using ionizing radiation, (iv) incidence of lungworm infection in sheep in Jammu and Kashmir State, (v) suitable dose of gamma radiation for attenuation, (vi) laboratory studies with radiation-attenuated D. filaria vaccine, (vii) serology of D. filaria infection, (viii) field trials with the radiation-attenuated vaccine, (ix) immune response of previously exposed lambs to vaccination, (x) comparative susceptibility of sheep and goats to infection with D. filaria, (xi) quantitative studies of D. filaria in lambs and (xii) production and supply of lungworm vaccine. (A.K.)

  12. Electron Effective-Attenuation-Length Database

    Science.gov (United States)

    SRD 82 NIST Electron Effective-Attenuation-Length Database (PC database, no charge)   This database provides values of electron effective attenuation lengths (EALs) in solid elements and compounds at selected electron energies between 50 eV and 2,000 eV. The database was designed mainly to provide EALs (to account for effects of elastic-eletron scattering) for applications in surface analysis by Auger-electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS).

  13. ATTENUATION AND FLANKING TRANSMISSION IN LIGHTWEIGHT STRUCTURES

    DEFF Research Database (Denmark)

    Brunskog, Jonas; Lhomond, Alice; Ohlrich, Mogens

    2007-01-01

    In this paper the attenuation and flanking transmissions of impact noise in lightweight building structures is studied using a modal approach. The structural field is mainly analysed, putting the main attention to the parts being important in the modelling. The amount of attenuation produced by the...... periodically reinforcing beams used in lightweight building structures is analysed. The consequence of these factors in modelling flanking transmission is also discussed....

  14. Anomalous Origin of the Left Atrial Branch from the Left Main Trunk

    Directory of Open Access Journals (Sweden)

    Arash Gholoobi

    2015-10-01

    Full Text Available A 78-year-old woman was referred for coronary angiography with the chief complaint of exertional angina and dyspnea of a very long duration during routine daily physical activities. She had a history of poorly controlled hypertension and dyslipidemia. Coronary angiography revealed diffuse three-vessel disease. Interestingly, an unusual branch was noted originating from the mid shaft of the left main trunk with a funnel-shaped root and travelling the course of a left atrial (LA branch (Figures 1 and 2.The left main coronary artery (LMCA usually bifurcates into two major branches: the left anterior descending (LAD and left circumflex (LCx arteries. In some patients, the LMCA trifurcates into the LAD, LCx, and a branch artery named ramus intermedius. This third branch arises between the LAD and LCx arteries. The LCx artery gives rise to one or two left atrial circumflex branches which supply the lateral and posterior aspects of the left atrium. According to our extensive search of the literature, this is the first case to be reported with the LA branch originating from the LMCA.

  15. Guided modes in asymmetric metal-cladding left-handed material waveguides

    Institute of Scientific and Technical Information of China (English)

    Ying He; Xia Zhang; Yanfang Yang; Chunfang Li

    2011-01-01

    @@ We investigate guided modes in the asymmetric waveguide structure with a left-handed material (LHM) layer surrounded by air and metal.A graphical method is proposed to determine the guided modes.New properties of the oscillating and surface guided modes, such as absence of the fundamental mode,coexistence of the oscillating and surface guided modes, fast attenuation of the surface guided modes, and mode degeneracy, are analyzed in detail.%We investigate guided modes in the asymmetric waveguide structure with a left-handed material (LHM) layer surrounded by air and metal. A graphical method is proposed to determine the guided modes. New properties of the oscillating and surface guided modes, such as absence of the fundamental mode, coexistence of the oscillating and surface guided modes, fast attenuation of the surface guided modes, and mode degeneracy, are analyzed in detail. We also investigate dispersive characteristics of the metal-LHMair optical waveguide. The propagation constant increases with decreasing slab thickness for the first-order oscillating mode, which is different from that in traditional metal-cladding waveguides.

  16. Some Characterizations of Left Weakly Regular Ordered Semigroups

    Institute of Scientific and Technical Information of China (English)

    TANC JIAN; XIE XIANG-YUN

    2011-01-01

    In this paper,the notion of left weakly regular ordered semigroups is introduced.Furthermore,left weakly regular ordered semigroups are characterized by the properties of their left ideals,right ideals and (generalized) bi-ideals,and also by the properties of their fuzzy left ideals,fuzzy right ideals and fuzzy (generalized) bi-ideals.

  17. Left bronchial artery arising from a replaced left hepatic artery in a patient with massive hemoptysis

    Energy Technology Data Exchange (ETDEWEB)

    Khil, Eun Kyung; Lee, Jae Myung [Dept. of Radiology, Soonchunhyang University College of Medicine, Bucheon Hospital, Bucheon (Korea, Republic of)

    2015-09-15

    A 70-year-old man with a 3-year history of bronchiectasis presented with massive hemoptysis that had lasted for 3 days. In our attempt to perform bronchial artery embolization, upper abdominal angiography was required to locate the left bronchial artery, which in this case was of anomalous origin, arising from a replaced left hepatic artery, which arose from the left gastric artery-a very unusual anatomical variant. We performed embolization with polyvinyl alcohol particles, and the patient's symptoms resolved completely, with no additional complications after conservative treatment.

  18. Effect of left bundle branch block on TIMI frame count

    OpenAIRE

    Hatice Tolunay; Ahmet Kasapkara; İsa Öner Yüksel; Nurcan Başar; Ayşe Saatcı Yaşar; Mehmet Bilge

    2010-01-01

    Aim: Left bundle branch block is an independent risk factorfor cardiac mortality. In this study we aimed to evaluatecoronary blood flow with TIMI frame count in patients with left bundle branch block and angiographically proven normal coronary arteries.Materials and methods: We retrospectively studied 17 patients with left bundle branch block and as a control group 16 patients without left bundle branch block. All patientshad angiographically proven normal coronary arteries.Left bundle branch...

  19. Healthy aging attenuates task-related specialization in the human medial temporal lobe

    DEFF Research Database (Denmark)

    Ramsøy, Thomas Z.; Liptrot, Matthew George; Skimminge, Arnold Jesper Møller;

    2012-01-01

    whether this greater MTL activation during encoding of objects varies with age. Fifty-four healthy individuals aged between 18 and 81 years underwent functional magnetic resonance imaging while they encoded and subsequently made new-old judgments on objects and positions. Region of interest (ROI) analysis......Recent research on aging has established important links between the neurobiology of normal aging and age-related decline in episodic memory, yet the exact nature of this relationship is still unknown. Functional neuroimaging of regions such as the medial temporal lobe (MTL) have produced...... hemisphere were defined as ROIs. Aging had an adverse effect on memory performance that was similar for memorizing objects or positions. In left and right MTL, relatively greater activation for object stimuli was attenuated in older individuals. Age-related attenuation in content specificity was most...

  20. Maximum likelihood estimation of the attenuated ultrasound pulse

    DEFF Research Database (Denmark)

    Rasmussen, Klaus Bolding

    1994-01-01

    The attenuated ultrasound pulse is divided into two parts: a stationary basic pulse and a nonstationary attenuation pulse. A standard ARMA model is used for the basic pulse, and a nonstandard ARMA model is derived for the attenuation pulse. The maximum likelihood estimator of the attenuated ultra...

  1. Dyscalculia, Dysgraphia, and Left-Right Confusion from a Left Posterior Peri-Insular Infarct

    Directory of Open Access Journals (Sweden)

    S. Bhattacharyya

    2014-01-01

    Full Text Available The Gerstmann syndrome of dyscalculia, dysgraphia, left-right confusion, and finger agnosia is generally attributed to lesions near the angular gyrus of the dominant hemisphere. A 68-year-old right-handed woman presented with sudden difficulty completing a Sudoku grid and was found to have dyscalculia, dysgraphia, and left-right confusion. Magnetic resonance imaging (MRI showed a focus of abnormal reduced diffusivity in the left posterior insula and temporoparietal operculum consistent with acute infarct. Gerstmann syndrome from an insular or peri-insular lesion has not been described in the literature previously. Pathological and functional imaging studies show connections between left posterior insular region and inferior parietal lobe. We postulate that the insula and operculum lesion disrupted key functional networks resulting in a pseudoparietal presentation.

  2. Dyscalculia, dysgraphia, and left-right confusion from a left posterior peri-insular infarct.

    Science.gov (United States)

    Bhattacharyya, S; Cai, X; Klein, J P

    2014-01-01

    The Gerstmann syndrome of dyscalculia, dysgraphia, left-right confusion, and finger agnosia is generally attributed to lesions near the angular gyrus of the dominant hemisphere. A 68-year-old right-handed woman presented with sudden difficulty completing a Sudoku grid and was found to have dyscalculia, dysgraphia, and left-right confusion. Magnetic resonance imaging (MRI) showed a focus of abnormal reduced diffusivity in the left posterior insula and temporoparietal operculum consistent with acute infarct. Gerstmann syndrome from an insular or peri-insular lesion has not been described in the literature previously. Pathological and functional imaging studies show connections between left posterior insular region and inferior parietal lobe. We postulate that the insula and operculum lesion disrupted key functional networks resulting in a pseudoparietal presentation. PMID:24817791

  3. New strict left bundle branch block criteria reflect left ventricular activation differences

    DEFF Research Database (Denmark)

    Emerek, Kasper Janus Grønn; Risum, Niels; Hjortshøj, Søren Pihlkjær;

    2015-01-01

    AIMS: Pacing lead electrical delays and strict left bundle branch block (LBBB) criteria were assessed against cardiac resynchronization therapy (CRT) outcome. METHODS: Forty-nine patients with LBBB and QRS duration >130 milliseconds underwent CRT-implantation. Sensed right ventricular to left...... ventricular electrical delay (RV-LV-IED) was measured. Response to CRT was defined as ≥15% decrease in left ventricular end-systolic volume. RESULTS: Eighteen of 20 (90%) patients with non-ischemic dilated cardiomyopathy (DCM) and 18 of 29 (62%) with ischemic heart disease (IHD) responded to CRT, p.... CONCLUSION: Interventricular electrical delay predicts left ventricular remodeling after CRT and new, strict ECG criteria of LBBB are superior in predicting remodeling....

  4. Mass loading induced dephasing in nanomechanical resonators

    Science.gov (United States)

    Atalaya, Juan

    2012-11-01

    This paper presents a study of dephasing of an underdamped nanomechanical resonator subject to random mass loading of small particles. A frequency noise model is presented which describes dephasing due to the attachment and detachment of particles at random points and particle diffusion along the resonator. This situation is commonly encountered in current mass measurement experiments using nanoelectromechanical (NEM) resonators. The conditions which can lead to inhomogeneous broadening and fine structure in the modes’ absorption spectra are discussed. It is also shown that the spectra of the higher-order cumulants of the (complex) vibrational mode amplitude are sensitive to the parameters characterizing the frequency noise process. Hence, measurement of these cumulants can provide information not only about the mass but also about other parameters of the particles (diffusion coefficient and attachment-detachment rates).

  5. Visual perceptual load induces inattentional deafness

    OpenAIRE

    Macdonald, James S P; Lavie, Nilli

    2011-01-01

    In this article, we establish a new phenomenon of “inattentional deafness” and highlight the level of load on visual attention as a critical determinant of this phenomenon. In three experiments, we modified an inattentional blindness paradigm to assess inattentional deafness. Participants made either a low- or high-load visual discrimination concerning a cross shape (respectively, a discrimination of line color or of line length with a subtle length difference). A brief pure tone was presente...

  6. Minimal Left-Right Dark Matter

    CERN Document Server

    Heeck, Julian

    2015-01-01

    We show that left-right-symmetric models can easily accommodate stable TeV-scale dark matter particles. The stability of a newly introduced multiplet arises either accidentally as in the Minimal Dark Matter framework or comes courtesy of the remaining unbroken $\\mathbb{Z}_2$ subgroup of $B-L$. As a minimal example we study left-right fermion triplets and quintuplets and show that they can form viable two-component dark matter. This approach is in particular valid for $SU(2)\\times SU(2)\\times U(1)$ models that explain the recent diboson excess at ATLAS in terms of a new charged gauge boson of mass 2 TeV.

  7. Minimal Left-Right Symmetric Dark Matter.

    Science.gov (United States)

    Heeck, Julian; Patra, Sudhanwa

    2015-09-18

    We show that left-right symmetric models can easily accommodate stable TeV-scale dark matter particles without the need for an ad hoc stabilizing symmetry. The stability of a newly introduced multiplet either arises accidentally as in the minimal dark matter framework or comes courtesy of the remaining unbroken Z_{2} subgroup of B-L. Only one new parameter is introduced: the mass of the new multiplet. As minimal examples, we study left-right fermion triplets and quintuplets and show that they can form viable two-component dark matter. This approach is, in particular, valid for SU(2)×SU(2)×U(1) models that explain the recent diboson excess at ATLAS in terms of a new charged gauge boson of mass 2 TeV.

  8. Left-right symmetric electroweak models

    International Nuclear Information System (INIS)

    We present a critical analysis of the spontaneous symmetry breaking and the Higgs sector of the conventional SU(2)L circle-times SU(2)R circle-times U(1)B-L left-right symmetric theory involving bi-doublet and triplet Higgs fields. We examine the phenomenological constraints imposed on the minimization of the Higgs potential arising from experimental observations, and explore the resulting consequences including the problem of ''fine- tuning'' arising from the hierarchy of mass scales involved. We show that it is non-trivial to satisfy all of these constraints. We contrast the benefits of this general class left-right models against the required ''fine-tuning'' necessary to force the phenomenology to conform to experimental fact. 17 refs., 1 fig

  9. Left Ventricular Noncompaction: A Distinct Genetic Cardiomyopathy?

    Science.gov (United States)

    Arbustini, Eloisa; Favalli, Valentina; Narula, Nupoor; Serio, Alessandra; Grasso, Maurizia

    2016-08-30

    Left ventricular noncompaction (LVNC) describes a ventricular wall anatomy characterized by prominent left ventricular (LV) trabeculae, a thin compacted layer, and deep intertrabecular recesses. Individual variability is extreme, and trabeculae represent a sort of individual "cardioprinting." By itself, the diagnosis of LVNC does not coincide with that of a "cardiomyopathy" because it can be observed in healthy subjects with normal LV size and function, and it can be acquired and is reversible. Rarely, LVNC is intrinsically part of a cardiomyopathy; the paradigmatic examples are infantile tafazzinopathies. When associated with LV dilation and dysfunction, hypertrophy, or congenital heart disease, the genetic cause may overlap. The prevalence of LVNC in healthy athletes, its possible reversibility, and increasing diagnosis in healthy subjects suggests cautious use of the term LVNC cardiomyopathy, which describes the morphology but not the functional profile of the cardiomyopathy. PMID:27561770

  10. EVENTRATION OF LEFT HEMIDIAPHRAGM MIMICKING AS CAVITY

    Directory of Open Access Journals (Sweden)

    Kansal

    2015-10-01

    Full Text Available Eventration of diaphragm is a condition in which there is abnormal elevation of the diaphragm as a result of thinning of muscular layer. It can be congenital as well as acquired. It is more common left sided. Herniation of the abdominal contents can be there. Clinical manifestations range from asymptomatic to life threatening respiratory distress requiring mechanical ventilator support. Ultrasound provides valuable information regarding the integrity of the diaphragm. Other imaging modalities include fluoroscopy, CT and MRI that provide valuable information when diagnosis is in doubt. We are presenting a case report of 25-year-old male with eventration of left hemidiaphragm mimicking as cavity. After taking detail history, examination and proper investigations we finally reached to this diagnosis.

  11. Anesthetic implications of total anomalous systemic venous connection to left atrium with left isomerism

    OpenAIRE

    Parimala Prasanna Simha; Muralidhara Danappa Patel; Jagadeesh, A. M.

    2012-01-01

    Total anomalous systemic venous connection (TASVC) to the left atrium (LA) is a rare congenital anomaly. An 11-year-old girl presented with complaints of palpitations and cyanosis. TASVC with left isomerism and noncompaction of LV was diagnosed after contrast echocardiogram and computed tomography angiogram. The knowledge of anatomy and pathophysiology is essential for the successful management of these cases. Anesthetic concerns in this case were polycythemia, paradoxical embolism and rhythm...

  12. Anomalous Origin of the Left Atrial Branch from the Left Main Trunk

    OpenAIRE

    Arash Gholoobi

    2015-01-01

    A 78-year-old woman was referred for coronary angiography with the chief complaint of exertional angina and dyspnea of a very long duration during routine daily physical activities. She had a history of poorly controlled hypertension and dyslipidemia. Coronary angiography revealed diffuse three-vessel disease. Interestingly, an unusual branch was noted originating from the mid shaft of the left main trunk with a funnel-shaped root and travelling the course of a left atrial (LA) branch (Figure...

  13. Is Left-Right Symmetry the Key?

    CERN Document Server

    Senjanovic, Goran

    2016-01-01

    Abdus Salam challenged the chiral gauge nature of the Standard Model by paving the road towards the Left-Right symmetric electro-weak theory. I describe here the logical and historical construction of this theory, by emphasising the pioneering and key role it played for neutrino mass. I show that it is a self-contained and predictive model with the Higgs origin of Majorana neutrino mass, in complete analogy with the SM situation regarding charged fermions.

  14. A difficult case of left atrial flutter

    Directory of Open Access Journals (Sweden)

    Reinder Evertz MD; Juan Acosta MD; David Andreu M.Sc; Josep Brugada MD, PhD; Lluis Mont MD, PhD

    2014-08-01

    Full Text Available A 55-year-old male was referred for a third ablation procedure because of recurrent atrial fibrillation. During re-isolation of the inferior right pulmonary vein the patient developed an atypical flutter with an clockwise activation pattern around the mitral annulus. Linear ablation at the left mitral isthmus transformed but did not terminate the tachycardia. The cavotricuspid isthmus proved to be a second critical isthmus and linear ablation at this site terminated the tachycardia.

  15. Left-Deviating Prism Adaptation in Left Neglect Patient: Reflexions on a Negative Result

    Directory of Open Access Journals (Sweden)

    Jacques Luauté

    2012-01-01

    Full Text Available Adaptation to right-deviating prisms is a promising intervention for the rehabilitation of patients with left spatial neglect. In order to test the lateral specificity of prism adaptation on left neglect, the present study evaluated the effect of left-deviating prism on straight-ahead pointing movements and on several classical neuropsychological tests in a group of five right brain-damaged patients with left spatial neglect. A group of healthy subjects was also included for comparison purposes. After a single session of exposing simple manual pointing to left-deviating prisms, contrary to healthy controls, none of the patients showed a reliable change of the straight-ahead pointing movement in the dark. No significant modification of attentional paper-and-pencil tasks was either observed immediately or 2 hours after prism adaptation. These results suggest that the therapeutic effect of prism adaptation on left spatial neglect relies on a specific lateralized mechanism. Evidence for a directional effect for prism adaptation both in terms of the side of the visuomanual adaptation and therefore possibly in terms of the side of brain affected by the stimulation is discussed.

  16. Interleukin-2/Anti-Interleukin-2 Immune Complex Attenuates Cardiac Remodeling after Myocardial Infarction through Expansion of Regulatory T Cells

    Directory of Open Access Journals (Sweden)

    Zhipeng Zeng

    2016-01-01

    Full Text Available CD4+CD25+Foxp3+ regulatory T cells (Treg cells have protective effects in wound healing and adverse ventricular remodeling after myocardial infarction (MI. We hypothesize that the interleukin- (IL- 2 complex comprising the recombinant mouse IL-2/anti-IL-2 mAb (JES6-1 attenuates cardiac remodeling after MI through the expansion of Treg. Mice were subjected to surgical left anterior descending coronary artery ligation and treated with either PBS or IL-2 complex. The IL-2 complex significantly attenuates ventricular remodeling, as demonstrated by reduced infarct size, improved left ventricular (LV function, and attenuated cardiomyocyte apoptosis. The IL-2 complex increased the percentage of CD4+CD25+Foxp3+ Treg cells, which may be recruited to the infarcted heart, and decreased the frequencies of IFN-γ- and IL-17-producing CD4+ T helper (Th cells among the CD4+Foxp3− T cells in the spleen. Furthermore, the IL-2 complex inhibited the gene expression of proinflammatory cytokines as well as macrophage infiltrates in the infarcted myocardium and induced the differentiation of macrophages from M1 to M2 phenotype in border zone of infarcted myocardium. Our studies indicate that the IL-2 complex may serve as a promising therapeutic approach to attenuate adverse remodeling after MI through expanding Treg cells specifically.

  17. Comparison of non-attenuation corrected and attenuation corrected myocardial perfusion SPE

    Directory of Open Access Journals (Sweden)

    Hasan Raza

    2016-09-01

    Conclusion: This study demonstrates that CT based attenuation corrected Tc-99mm sestamibi SPECT myocardial perfusion imaging significantly improved the specificity of the RCA territory compared with non-attenuation corrected Tc-99mm sestamibi SPECT myocardial perfusion imaging in both genders irrespective of BMI.

  18. Cine CT for Attenuation Correction in Cardiac PET/CT

    OpenAIRE

    Alessio, Adam M.; Kohlmyer, Steve; Branch, Kelley; Chen, Grace; Caldwell, James; Kinahan, Paul

    2007-01-01

    In dual-modality PET/CT systems, the CT scan provides the attenuation map for PET attenuation correction. The current clinical practice of obtaining a single helical CT scan provides only a snapshot of the respiratory cycle, whereas PET occurs over multiple respiratory cycles. Misalignment of the attenuation map and emission image because of respiratory motion causes errors in the attenuation correction factors and artifacts in the attenuation-corrected PET image. To rectify this problem, we ...

  19. Attenuation of ear muffs in Canadian mines

    Energy Technology Data Exchange (ETDEWEB)

    Savich, M.U.

    1979-12-01

    The main characteristics of eleven commercially available ear muffs were investigated in the laboratory and analyzed by a psychophysical and a physical method. Nine ear muffs were tested in mines. The three best muffs had bands passing behind the head. The ear muff with a support strap, which improves comfort and maintains a good fit during wear, showed the best attenuation. Causes of poor attenuation are listed. None of the ear muffs tested had all the characteristics desirable in an ideal unit. Because of unsatisfactory attenuation in working conditions, it should be a mandatory requirement that workers wear both ear muffs and ear plugs if the noise level is higher than 105 dBA.

  20. Research on Nanosecond Pulse Corona Discharge Attenuation

    International Nuclear Information System (INIS)

    A line-to-plate reactor was set-up in the experimental study on the application of nanosecond pulsed corona discharge plasma technology in environmental pollution control. Investigation on the attenuation and distortion of the amplitude of the pulse wave front and the discharge image as well as the waveform along the corona wire was conducted. The results show that the wave front decreases sharply during the corona discharge along the corona wire. The higher the amplitude of the applied pulse is, the more the amplitude of the wave front decreased. The wave attenuation responds in a lower corona discharge inversely. To get a higher efficiency of the line-to-plate reactor a sharp attenuation of the corona has to be considered in practical design

  1. Finite Element Analysis of Honeycomb Impact Attenuator

    Science.gov (United States)

    Yang, Seung-Yong; Choi, Seung-Kyu; Kim, Nohyu

    To participate in Student Formula Society of Automotive Engineers (SAE) competitions, it is necessary to build an impact attenuator that would give an average deceleration not to exceed 20g when it runs into a rigid wall. Students can use numerical simulations or experimental test data to show that their car satisfies this safety requirement. A student group to study formula cars at the Korea University of Technology and Education has designed a vehicle to take part in a SAE competition, and a honeycomb structure was adopted as the impact attenuator. In this paper, finite element calculations were carried out to investigate the dynamic behavior of the honeycomb attenuator. Deceleration and deformation behaviors were studied. Effect of the yield strength was checked by comparing the numerical results. ABAQUS/Explicit finite element code was used.

  2. Live attenuated vaccines for invasive Salmonella infections.

    Science.gov (United States)

    Tennant, Sharon M; Levine, Myron M

    2015-06-19

    Salmonella enterica serovar Typhi produces significant morbidity and mortality worldwide despite the fact that there are licensed Salmonella Typhi vaccines available. This is primarily due to the fact that these vaccines are not used in the countries that most need them. There is growing recognition that an effective invasive Salmonella vaccine formulation must also prevent infection due to other Salmonella serovars. We anticipate that a multivalent vaccine that targets the following serovars will be needed to control invasive Salmonella infections worldwide: Salmonella Typhi, Salmonella Paratyphi A, Salmonella Paratyphi B (currently uncommon but may become dominant again), Salmonella Typhimurium, Salmonella Enteritidis and Salmonella Choleraesuis (as well as other Group C Salmonella). Live attenuated vaccines are an attractive vaccine formulation for use in developing as well as developed countries. Here, we describe the methods of attenuation that have been used to date to create live attenuated Salmonella vaccines and provide an update on the progress that has been made on these vaccines.

  3. Research on Nanosecond Pulse Corona Discharge Attenuation

    Institute of Scientific and Technical Information of China (English)

    HE Zheng-hao; XU Huai-li; BAI Jing; YU Fu-sheng; HU Feng; LI Jin

    2007-01-01

    A line-to-plate reactor was set-up in the experimental study on the application of nanosecond pulsed corona discharge plasma technology in environmental pollution control.Investigation on the attenuation and distortion of the amplitude of the pulse wave front and the discharge image as well as the waveform along the corona wire was conducted.The results show that the wave front decreases sharply during the corona discharge along the corona wire.The higher the amplitude of the applied pulse is,the more the amplitude of the wave front decreased.The wave attenuation responds in a lower corona discharge inversely.To get a higher efficiency of the line-to-plate reactor a sharp attenuation of the corona has to be considered in practical design.

  4. Graphene-Based Waveguide Terahertz Wave Attenuator

    Science.gov (United States)

    Jian-rong, Hu; Jiu-sheng, Li; Guo-hua, Qiu

    2016-07-01

    We design an electrically controllable terahertz wave attenuator by using graphene. We show that terahertz wave can be confined and propagate on S-shaped graphene waveguide with little radiation losses, and the confined terahertz wave is further manipulated and controlled via external applied voltage bias. The simulated results show that, when chemical potential changes from 0.03 into 0.05 eV, the extinction ratio of the terahertz wave attenuator can be tuned from 1.28 to 39.42 dB. Besides the simplicity, this novel terahertz wave attenuator has advantages of small size (24 × 30 μm2), a low insertion loss, and good controllability. It has a potential application for forthcoming planar terahertz wave integrated circuit fields.

  5. The New Left in the European Democracies: The Case of the German Radical Left

    Directory of Open Access Journals (Sweden)

    Marco Damiani

    2015-03-01

    Full Text Available The new form of the social and political conflict cannot be explained by the traditional categories of right and left, but it articulates to them on two plans, that of the establishment, intended like plan of the structured political conflict from the traditional actors, and that of the anti-establishment, in which new representations of politics emerge. The New Left is characterized by type of intermittent participation and new perspectives on mobilization inside the parties and the social movements. This type of parties differs moreover from the traditional ones left of the socialist and social democratic left in not arranging of organizations collaterals placed under the direction of the leadership of the same party. The mobilization that spontaneously assumes not conventional forms of active participation of the citizens, or is primed by the action of an associative network of which the same parties take part, than however does not monopo-lize the collective action. In this regard, the attention will be dedicated to the study of Die Linke: an anti-establishment party of the non-socialist German left-wing, heir to the communist tradition. The choice was affected to the German model because: 1 Germany is a country with a strong social democratic tradition, but 25 years after the fall of the Berlin Wall the German political system identifies a new antagonist political party; 2 Die Linke represents an interesting case in the political landscape of the European radical left because is a one-party that gives up at the federation of parties to try to unify the political parties of German radical left-wing.

  6. The Maximal Graded Left Quotient Algebra of a Graded Algebra

    Institute of Scientific and Technical Information of China (English)

    Gonzalo ARANDA PINO; Mercedes SILES MOLINA

    2006-01-01

    We construct the maximal graded left quotient algebra of every graded algebra A without homogeneous total right zero divisors as the direct limit of graded homomorphisms (of left A-modules)from graded dense left ideals of A into a graded left quotient algebra of A. In the case of a superalgebra,and with some extra hypothesis, we prove that the component in the neutral element of the group of the maximal graded left quotient algebra coincides with the maximal left quotient algebra of the component in the neutral element of the group of the superalgebra.

  7. Correlation of the myocardial perfusion corrected by attenuation with the coronariography. Preliminary results; Correlacion de la perfusion miocardica corregida por atenuacion con la coronariografia

    Energy Technology Data Exchange (ETDEWEB)

    Garcia C, S.E.; Garcia O, R. [Servicio de Medicina Nuclear, Centro Medico ABC, Campis Observatorio, IAP (Mexico)

    2005-07-01

    The attenuation that suffers the radiation in the soft tissues of the hinders the appropriate interpretation of the myocardial perfusion studies, for what have been implemented attenuation correction systems to reduce the attenuation for soft tissues and to provide myocardial perfusion images more accurate in the diagnosis of coronary illness. The objective was to evaluate the utility of an attenuation correction system (with source of Gadolinium 153) to minimize the devices that look like true defects of myocardial perfusion, caused by soft tissues (mammary tissue, thoracic wall, abdomen, left hemi diaphragm), and to compare those interpretations of the studies with the interpretations of the corresponding coronariographies. The method consists of 95 electronic files which were revised with the concept of heart catheterization, being identified 20 patients from the masculine sex to those that underwent coronariography among May 1999 and December 2002, and that they had study of myocardial perfusion in a maximum period of 3 months foresaw to the invasive procedure. (Author)

  8. Is there seismic attenuation in the mantle?

    Science.gov (United States)

    Ricard, Y.; Durand, S.; Montagner, J.-P.; Chambat, F.

    2014-02-01

    The small scale heterogeneity of the mantle is mostly due to the mixing of petrological heterogeneities by a smooth but chaotic convection and should consist in a laminated structure (marble cake) with a power spectrum S(k) varying as 1/k, where k is the wavenumber of the anomalies. This distribution of heterogeneities during convective stirring with negligible diffusion, called Batchelor regime is documented by fluid dynamic experiments and corresponds to what can be inferred from geochemistry and seismic tomography. This laminated structure imposes density, seismic velocity and potentially, anisotropic heterogeneities with similar 1/k spectra. A seismic wave of wavenumber k0 crossing such a medium is partly reflected by the heterogeneities and we show that the scattered energy is proportional to k0S(2k0). The reduction of energy for the propagating wave appears therefore equivalent to a quality factor 1/Q∝k0S(2k0). With the specific 1/k spectrum of the mantle, the resulting apparent attenuation should therefore be frequency independent. We show that the total contribution of 6-9% RMS density, velocity and anisotropy would explain the observed S and P attenuation of the mantle. Although these values are large, they are not unreasonable and we discuss how they depend on the range of frequencies over which the attenuation is explained. If such a level of heterogeneity were present, most of the attenuation of the Earth would be due to small scale scattering by laminations, not by intrinsic dissipation. Intrinsic dissipation must certainly exist but might correspond to a larger, yet unobserved Q. This provocative result would explain the very weak frequency dependence of the attenuation, and the fact that bulk attenuation seems negligible, two observations that have been difficult to explain for 50 years.

  9. Novel Toll-like receptor-4 deficiency attenuates trastuzumab (Herceptin induced cardiac injury in mice

    Directory of Open Access Journals (Sweden)

    Yousif Nasser

    2011-10-01

    Full Text Available Abstract Background Cardiac inflammation and generation of oxidative stress are known to contribute to trastuzumab (herceptin induced cardiac toxicity. Toll-like receptors (TLRs are a part of the innate immune system and are involved in cardiac stress reactions. Since TLR4 might play a relevant role in cardiac inflammatory signaling, we investigated whether or not TLR4 is involved in trastuzumab induced cardiotoxicity. Methods Seven days after a single injection of herceptin (2 mg/kg; i.p., left ventricular pressure volume loops were measured in HeN compotent (TLR4+/+ and HeJ mutant (TLR4-/- treated with trastuzumab and control mice. Immunofluorescent staining for monocyte infiltration and analyses of plasma by (ELISAs for different chemokines including: MCP-1and tumor necrosis factor-α (TNF-α, Western immunoblotting assay for ICAM-1, and used troponin I for cardiac injury marker. Results Trastuzumab injection resulted in an impairment of left ventricular function in TLR-4 competent (HeN, in contrast TLR4-/- trastuzumab mice showed improved left ventricular function EF%, CO; p -/-; p -/-, marked reduction of myocardial troponin-I levels in TLR4-deficient mice. Data are presented as means ± SE; n = 8 in each group p Conclusions Treatment with trastuzumab induces an inflammatory response that contributes to myocardial tissue TLR4 mediates chemokine expression (TNF-α, MCP-1and ICAM-1, so in experimental animals TLR4 deficiency improves left ventricular function and attenuates pathophysiological key mechanisms in trastuzumab induced cardiomyopathy.

  10. Early exercise training normalizes myofilament function and attenuates left ventricular pump dysfunction in mice with a large myocardial infarction

    NARCIS (Netherlands)

    M.C. de Waard (Monique); J. van der Velden (Jolanda); V. Bito (Virginie); S. Ozdemir (Semir); L. Biesmans (Liesbeth); N.M. Boontje (Nicky); D.H. Dekkers (Dick); K. Schoonderwoerd (Kees); J.C.H. Schuurbiers (Johan); R. de Crom (Rini); G.J.M. Stienen (Ger); K.R. Sipido (Karin); J.M.J. Lamers (Jos); D.J.G.M. Duncker (Dirk)

    2007-01-01

    textabstractThe extent and mechanism of the cardiac benefit of early exercise training following myocardial infarction (MI) is incompletely understood, but may involve blunting of abnormalities in Ca-handling and myofilament function. Consequently, we investigated the effects of 8-weeks of voluntary

  11. Radiographic and echocardiographic assessment of left atrial size in 100 cats with acute left-sided congestive heart failure.

    Science.gov (United States)

    Schober, Karsten E; Wetli, Ellen; Drost, Wm Tod

    2014-01-01

    The aims of this study were to evaluate left atrial size in cats with acute left-sided congestive heart failure. We hypothesized that left atrial size as determined by thoracic radiography can be normal in cats with acute left-sided congestive heart failure. One hundred cats with acute left-sided congestive heart failure in which thoracic radiography and echocardiography were performed within 12 h were identified. Left atrial size was evaluated using right lateral and ventrodorsal radiographs. Measurements were compared to two-dimensional echocardiographic variables of left atrial size and left ventricular size. On echocardiography, left atrial enlargement was observed in 96% cats (subjective assessment) whereas maximum left atrial dimension was increased (>15.7 mm) in 93% cats. On radiographs left atrial enlargement (subjective assessment) was found in 48% (lateral view), 53% (ventrodorsal view), and 64% (any view) of cats whereas left atrial enlargement was absent in 36% of cats in both views. Agreement between both methods of left atrial size estimation was poor (Cohen's kappa 0.17). Receiver operating characteristic curve analysis identified a maximum echocardiographic left atrial dimension of approximately 20 mm as the best compromise (Youden index) between sensitivity and specificity in the prediction of radiographic left atrial enlargement. Left atrial enlargement as assessed by thoracic radiography may be absent in a clinically relevant number of cats with congestive heart failure. Therefore, normal left atrial size on thoracic radiographs does not rule out presence of left-sided congestive heart failure in cats with clinical signs of respiratory distress.

  12. Ultrasound transmission attenuation tomography using energy-scaled amplitude ratios

    Science.gov (United States)

    Chen, Ting; Shin, Junseob; Huang, Lianjie

    2016-04-01

    Ultrasound attenuation of breast tumors is related to their types and pathological states, and can be used to detect and characterize breast cancer. Particularly, ultrasound scattering attenuation can infer the margin properties of breast tumors. Ultrasound attenuation tomography quantitatively reconstructs the attenuation properties of the breast. Our synthetic-aperture breast ultrasound tomography system with two parallel transducer arrays records both ultrasound reflection and transmission signals. We develop an ultrasound attenuation tomography method using ultrasound energy-scaled amplitude decays of ultrasound transmission signals and conduct ultrasound attenuation tomography using a known sound-speed model. We apply our ultrasound transmission attenuation tomography method to a breast phantom dataset, and compare the ultrasound attenuation tomography results with conventional beamforming ultrasound images obtained using reflection signals. We show that ultrasound transmission attenuation tomography complements beamforming images in identifying breast lesions.

  13. Dual (type IV left anterior descending artery

    Directory of Open Access Journals (Sweden)

    Ozdil Baskan

    2013-11-01

    Full Text Available Congenital coronary artery anomalies are uncommon. Dual left anterior descending coronary artery (LAD is defined as the presence of two LADs within the anterior interventricular sulcus (AIVS, and is classified into four types. Type IV is a rarely reported subtype and differs from the others, with a long LAD originating from the right coronary artery (RCA. Dual LAD is a benign coronary artery anomaly, but should be recognised especially before interventional procedures. With the increasing use of multidedector computed tomography (MDCT, it is essential for radiologists to be aware of this entity and the cross-sectional findings.

  14. Shared Frailty Model for Left-Truncated Multivariate Survival Data

    DEFF Research Database (Denmark)

    Jensen, Henrik; Brookmeyer, Ron; Aaby, Peter;

    multivariate survival data, left truncation, multiplicative hazard model, shared gamma frailty, conditional model, piecewise exponential model, childhood survival......multivariate survival data, left truncation, multiplicative hazard model, shared gamma frailty, conditional model, piecewise exponential model, childhood survival...

  15. Heart Failure with Transient Left Bundle Branch Block in the Setting of Left Coronary Fistula

    Directory of Open Access Journals (Sweden)

    Stephen P. Juraschek

    2011-01-01

    Full Text Available Coronary arterial fistulas are rare communications between vessels or chambers of the heart. Although cardiac symptoms associated with fistulas are well described, fistulas are seldom considered in the differential diagnosis of acute myocardial ischemia. We describe the case of a 64-year-old man who presented with left shoulder pain, signs of heart failure, and a new left bundle branch block (LBBB. Cardiac catheterization revealed a small left anterior descending (LAD-to-pulmonary artery (PA fistula. Diuresis led to subjective improvement of the patient's symptoms and within several days the LBBB resolved. We hypothesize that the coronary fistula in this patient contributed to transient ischemia of the LAD territory through a coronary steal mechanism. We elected to observe rather than repair the fistula, as his symptoms and ECG changes resolved with treatment of his heart failure.

  16. LEFT ATRIAL VOLUME INDEX (LAVI IN THE EVALUATION OF LEFT VENTRICULAR DIASTOLIC DYSFUNCTION

    Directory of Open Access Journals (Sweden)

    Malladi Srinivasa

    2015-02-01

    Full Text Available Although cardiac performance is traditionally focused on Ejection fraction an index of systolic function , diastolic function has been found to play an important role in morbidity and mortality. Diastolic heart failure constitutes about 20 - 40% admissions of heart failure. Left atrium is directly exposed to LV pressures in diastole. Chronic sustained elevation of elevated diastolic filling pressures result in left atrial remodeling resulting in its enlargement. Traditionally left atrial size is determined from the parasternal long axis vie w at end systole. However the left atrial volume is a better measure of LA size and provides better prognostic value. The influence of body surface area is corrected by dividing LA volume by body surface area to get LA volume index ( LAVI. The normal value for all age groups is 22 ± 6 ml/m . 1 AIM: To measure the left atrial volume and diastolic function in 60 subjects and to study the correlation between left atrial volume and diastolic dysfunction METHODS: 60 subjects ( 40 with diastolic dysfunction and 20 c ontrols referred to the echocardiography were studied. All subjects underwent trans thoracic echocardiography and Doppler imaging Diastolic filling was categorized as normal (grade 0 impaired relaxation (grade 1 , pseudo normal pattern (grade 2 , restric tive filling (grade 3. LA volume is measured by biplane area length method and indexed to BSA ( LAVI Results : Among diastolic dysfunction group , 25(62.5% had Grade 1 diastolic dysfunction , 6(15% have grade 2 and 9(22.5% had grade3 diastolic dysfunction . Progressive increase in LAVI was seen with increasing severity of diastolic dysfunction. Mean LAVI in normal persons was 23.49±4.009 ml/ sqm and in patients with diastolic dysfunction , it was 29.38±4.45 , 39.44±8.19 , 44.33±5.54 ml/sqm in grade 1 , grade2 and grade3 diastolic dysfunctions groups respectively.

  17. Isolated Left Pulmonary Artery Agenesis: A Case Report

    OpenAIRE

    Tansel Ansal Balcı; Zehra Pınar Koç; Gamze Kırkıl; Ahmet Kürşad Poyraz

    2012-01-01

    Unilateral pulmonary artery agenesis without any cardiovascular malformation is a rare anomaly. We present the imaging findings of a patient who was diagnosed as isolated left pulmonary artery agenesis. A 27-year-old female patient was admitted to our hospital due to dyspnea during exercise for five years. Chest X-ray revealed minimally small left pulmonary hilum and left lung. She was admitted to our clinic with the suspicion of pulmonary artery pathology. Absent perfusion of the left lung w...

  18. Switching Control for Adaptive Disturbance Attenuation

    NARCIS (Netherlands)

    Battistelli, Giorgio; Mari, Daniele; Selvi, Daniela; Tesi, Alberto; Tesi, Pietro

    2014-01-01

    The problem of adaptive disturbance attenuation is addressed in this paper using a switching control approach. A finite family of stabilizing controllers is pre-designed, with the assumption that, for any possible operating condition, at least one controller is able to achieve a prescribed level of

  19. Microwave attenuation with composite of copper microwires

    Energy Technology Data Exchange (ETDEWEB)

    Gorriti, A.G.; Marin, P. [Instituto de Magnetismo Aplicado, (UCM-ADIF-CSIC) and Departamento de Fisica de Materiales (UCM). P.O. Box 155, Las Rozas, Madrid 28230 (Spain); Cortina, D. [Micromag S.L., Las Rozas, Madrid 28230 (Spain); Hernando, A., E-mail: antonio.hernando@adif.e [Instituto de Magnetismo Aplicado, (UCM-ADIF-CSIC) and Departamento de Fisica de Materiales (UCM). P.O. Box 155, Las Rozas, Madrid 28230 (Spain); Micromag S.L., Las Rozas, Madrid 28230 (Spain)

    2010-05-15

    It is shown that copper microwires composite media attenuates microwave reflection of metallic surfaces. We show how the distance to the metallic surface, as well as the length and volume fraction of microwires, determine the frequency of maximum absorption and the return loss level. Furthermore, we were able to fit the experimental results with a theoretical model based on Maxwell-Garnett mixing formula.

  20. Attenuation of PRRSV by chimera construction

    Science.gov (United States)

    Two genetically distinct infectious recombinant virus clones (pMLV, constructed from Ingelvac® PRRS MLV and pMN184, constructed from virulent strain MN184) were developed to study attenuation of contemporary PRRSV. Two reciprocal chimeric clones (pMLVORF1/MN184 and pMN184ORF1/MLV) were then constru...

  1. ULTRASONIC ATTENUATION IN MIXED STATE OF NIOBIUM

    OpenAIRE

    Dominec, J.; MÍŠek, K.

    1987-01-01

    We have investigated the attenuation of ultrasonic waves in the mixed state of niobium, where a remarkable dip appears near the lower critical field . The measurement has been performed on one sample for various orientations of the wave vector and of the principal crystallographic axes of the sample with respect to external magnetic field.

  2. Hadron attenuation at HERMES and JLab

    OpenAIRE

    Falter, T.; Cassing, W.; Gallmeister, K.; Mosel, U.

    2005-01-01

    We investigate the attenuation of hadrons in deep inelastic lepton-nucleus scattering in the kinematical regime of the HERMES and Jefferson Lab experiments. The calculation is carried out in the framework of a BUU transport model. Our results indicate a strong influence of (pre)hadronic final state interactions on the observed multiplicity ratios.

  3. Attenuation correction for small animal PET tomographs

    Energy Technology Data Exchange (ETDEWEB)

    Chow, Patrick L [David Geffen School of Medicine at UCLA, Crump Institute for Molecular Imaging, University of California, 700 Westwood Plaza, Los Angeles, CA 90095 (United States); Rannou, Fernando R [Departamento de Ingenieria Informatica, Universidad de Santiago de Chile (USACH), Av. Ecuador 3659, Santiago (Chile); Chatziioannou, Arion F [David Geffen School of Medicine at UCLA, Crump Institute for Molecular Imaging, University of California, 700 Westwood Plaza, Los Angeles, CA 90095 (United States)

    2005-04-21

    Attenuation correction is one of the important corrections required for quantitative positron emission tomography (PET). This work will compare the quantitative accuracy of attenuation correction using a simple global scale factor with traditional transmission-based methods acquired either with a small animal PET or a small animal x-ray computed tomography (CT) scanner. Two phantoms (one mouse-sized and one rat-sized) and two animal subjects (one mouse and one rat) were scanned in CTI Concorde Microsystem's microPET (registered) Focus{sup TM} for emission and transmission data and in ImTek's MicroCAT{sup TM} II for transmission data. PET emission image values were calibrated against a scintillation well counter. Results indicate that the scale factor method of attenuation correction places the average measured activity concentration about the expected value, without correcting for the cupping artefact from attenuation. Noise analysis in the phantom studies with the PET-based method shows that noise in the transmission data increases the noise in the corrected emission data. The CT-based method was accurate and delivered low-noise images suitable for both PET data correction and PET tracer localization.

  4. UFO in the Left Atrium: How to Capture Metal Debris Floating in the Left Atrium.

    Science.gov (United States)

    Fassini, Gaetano; Moltrasio, Massimo; Conti, Sergio; Biagioli, Viviana; Tondo, Claudio

    2016-06-01

    Electrophysiology procedures involving left atrium navigation are becoming more frequent, mostly due to the increase of atrial fibrillation ablation. Mapping catheters of different shapes and size as well as dedicated sheaths are mandatory tools for the accomplishment of procedural end point. Therefore, technical issues are expected, usually unrelated to significant risk. However, any accidental intra-atrial device loss of integrity implies a risk of cerebrovascular embolization. The lack of clear evidence on how to manage these events and the need for a quick solution complicate the scenario. We report an empirical solution in the case of debris floating in the left atrium. PMID:26395524

  5. UFO in the Left Atrium: How to Capture Metal Debris Floating in the Left Atrium.

    Science.gov (United States)

    Fassini, Gaetano; Moltrasio, Massimo; Conti, Sergio; Biagioli, Viviana; Tondo, Claudio

    2016-06-01

    Electrophysiology procedures involving left atrium navigation are becoming more frequent, mostly due to the increase of atrial fibrillation ablation. Mapping catheters of different shapes and size as well as dedicated sheaths are mandatory tools for the accomplishment of procedural end point. Therefore, technical issues are expected, usually unrelated to significant risk. However, any accidental intra-atrial device loss of integrity implies a risk of cerebrovascular embolization. The lack of clear evidence on how to manage these events and the need for a quick solution complicate the scenario. We report an empirical solution in the case of debris floating in the left atrium.

  6. Anesthetic implications of total anomalous systemic venous connection to left atrium with left isomerism

    Directory of Open Access Journals (Sweden)

    Parimala Prasanna Simha

    2012-01-01

    Full Text Available Total anomalous systemic venous connection (TASVC to the left atrium (LA is a rare congenital anomaly. An 11-year-old girl presented with complaints of palpitations and cyanosis. TASVC with left isomerism and noncompaction of LV was diagnosed after contrast echocardiogram and computed tomography angiogram. The knowledge of anatomy and pathophysiology is essential for the successful management of these cases. Anesthetic concerns in this case were polycythemia, paradoxical embolism and rhythm abnormalities. The patient was successfully operated by rerouting the systemic venous connection to the right atrium.

  7. Left ventricular thrombus formation after repair of anomalous left coronary artery from the pulmonary artery.

    Science.gov (United States)

    Freud, Lindsay R; Koenig, Peter R; Russell, Hyde M; Patel, Angira

    2014-04-01

    Although thrombus formation following myocardial infarction in adults is well known, intracardiac thrombosis in children is uncommon. We report the case of a large left ventricular thrombus in an infant with ischemic cardiomyopathy secondary to anomalous origin of the left coronary artery from the pulmonary artery. Given its mobility and protrusion across the aortic valve, the patient underwent urgent thrombus removal through a transaortic approach. There were no embolic or neurologic complications. This case highlights that thrombectomy may be performed safely and successfully in critically ill pediatric patients.

  8. Neonatal small left colon in an infant with cystic fibrosis

    International Nuclear Information System (INIS)

    A small left colon has been observed in neonates due to several causes: aganglionosis, meconium plug, and neonatal small left colon syndrome. We report a case of small left colon in an infant with cystic fibrosis, underscoring the need to consider this diesease in the diagnostic work up. (orig.)

  9. Left ventricular hypertrophy in patients treated with regular hemodialyses

    OpenAIRE

    Petrović Dejan; Stojimirović Biljana

    2008-01-01

    Left ventricular hypertrophy is the main risk factor for development of cardiovascular morbidity and mortality in patients on hemodialysis. Left ventricular hypertrophy is found in 75% of the patients treated with hemodialysis. Risk factors for left ventricular hypertrophy in patients on hemodialysis include: blood flow through arterial-venous fistula, anemia, hypertension, increased extracellular fluid volume, oxidative stress, microinflammation, hyperhomocysteinemia, secondary hyperpara- th...

  10. Spatial Deficit in Familial Left-Handed Children.

    Science.gov (United States)

    And Others; Eme, Robert

    1978-01-01

    The study evaluated the hypothesis that familial left-handed children, who presumably have bilateral representation of language ability, should show an impairment in spatial abiblity on 44 children (22 right handed, 11 familial left handed, and 11 nonfamilial left handed) whose average age was 8 years old. (Author/PHR)

  11. Learning Conflict Among Mixed-Dominance Left-Handed Individuals.

    Science.gov (United States)

    Blai, Boris, Jr.

    This study investigates the hypothesis that it is mixed-dominance among left handers (i.e. left handedness and right eye and/or foot dominance), that is related to academic learning difficulties among such individuals, rather than the generally held notion that their difficulties stem from the fact that they are left handers in a "right handed…

  12. Left-Handed Children--Are They Losing Out?

    Science.gov (United States)

    Milsom, Lauren

    1995-01-01

    Discusses difficulties faced by left-handed children in everyday schoolwork. Highlights include right-handed bias of toys, clothing, and tools; the need for guidance in handwriting; problem areas including domestic science, arts and crafts, and metal and woodwork; left-hand advantages in sports and creative arts; and the European Left-Handers Club…

  13. Left-Handed Students: A Forgotten Minority. Fastback 399.

    Science.gov (United States)

    Kelly, Evelyn B.

    This fastback, a booklet bound "left-handed," is designed to help educators become aware of the problems faced by left-handed students in school and to suggest ways that many of the problems might be solved. Following an introduction discussing a personal experience with left-handedness, the booklet continues with a brief history of the treatment…

  14. Nitrous Oxide Decomposition on the Binuclear $\\left(\\mu -O \\right)\\left(\\mu -OH \\right)Fe \\right>$ Center in Fe-ZSM-5 Zeolite

    OpenAIRE

    Guesmi, Hazar; Berthomieu, Dorothee; Kiwi-Minsker, Dorothee

    2008-01-01

    The reaction mechanism for nitrous oxide (${N}_{2}O$) direct decomposition into molecular nitrogen and oxygen was studied on binuclear iron sites in Fe-ZSM-5 zeolite using the density functional theory (DFT). Starting from the hydroxylated bi-iron complex ${\\left}^{+}$, a reductive dehydroxylation pathway was proposed to justify the formation of the active site ${\\left}^{+}$. The latter contains two FeII ions linked via oxo and hydroxo bridges, ${{Z}^{-}\\left}^{+}$, and for the first time was...

  15. Deformation behaviors of sandy subgrade soil under traffic load-induced stress path%交通荷载应力路径下砂土地基变形特性研究

    Institute of Scientific and Technical Information of China (English)

    熊焕; 郭林; 蔡袁强

    2016-01-01

    在交通荷载作用下,地基土单元不仅偏应力大小周期性变化而且主应力轴连续旋转。为了研究交通荷载应力路径下地基土单元排水变形特性,利用动态空心圆柱仪对K0固结下饱和砂土进行了一系列“苹果型”动力循环应力路径以及普通动力循环应力路径试验。两组应力路径试验结果的对比表明交通荷载应力路径引起的主应力轴连续旋转会加速竖向永久变形的累积,并且对竖向回弹模量具有软化作用,而且随着循环应力比的增大,两种应力路径下变形特性差异变得更加明显。最后,基于Uzan回弹模量模型提出了相应的修正公式用来考虑主应力轴旋转效应。%Under traffic load, the magnitude of deviatoric stress of subgrade soilvariesperiodically, and the principal stress axis rotates continually. In order tostudy the draineddeformationbehaviorscharacteristics of subgrade soil due to traffic load-induced stress path, a series of apple-shaped dynamic cyclic stress path tests and conventional dynamic stress path tests are conducted onK0-consolidated saturated sand using the dynamic hollow cylinder apparatus.Comparisons between the results under the two different stress paths indicate that thecontinuous rotation of the principal stress axis will accelerate the accumulation of the vertical permanent strains and aggravate the degradation of the resilient modulus. And with the increasing of CSR, the discrepancies in thedeformationbehaviors under different stress paths become more apparent. Finally, amodified formula for the resilient modulusis proposed to evaluate the principal stress rotation effects based on the Uzan model.

  16. Effects of sedation on echocardiographic variables of left atrial and left ventricular function in healthy cats.

    Science.gov (United States)

    Ward, Jessica L; Schober, Karsten E; Fuentes, Virginia Luis; Bonagura, John D

    2012-10-01

    Although sedation is frequently used to facilitate patient compliance in feline echocardiography, the effects of sedative drugs on echocardiographic variables have been poorly documented. This study investigated the effects of two sedation protocols on echocardiographic indices in healthy cats, with special emphasis on the assessment of left atrial size and function, as well as left ventricular diastolic performance. Seven cats underwent echocardiography (transthoracic two-dimensional, spectral Doppler, color flow Doppler and tissue Doppler imaging) before and after sedation with both acepromazine (0.1 mg/kg IM) and butorphanol (0.25 mg/kg IM), or acepromazine (0.1 mg/kg IM), butorphanol (0.25 mg/kg IM) and ketamine (1.5 mg/kg IV). Heart rate increased significantly following acepromazine/butorphanol/ketamine (mean±SD of increase, 40±26 beats/min) and non-invasive systolic blood pressure decreased significantly following acepromazine/butorphanol (mean±SD of decrease, 12±19 mmHg). The majority of echocardiographic variables were not significantly different after sedation compared with baseline values. Both sedation protocols resulted in mildly decreased left ventricular end-diastolic dimension and mildly increased left ventricular end-diastolic wall thickness. This study therefore failed to demonstrate clinically meaningful effects of these sedation protocols on echocardiographic measurements, suggesting that sedation with acepromazine, butorphanol and/or ketamine can be used to facilitate echocardiography in healthy cats. PMID:22577049

  17. Rare Anomalous Origin of Superior Left Pulmonary Artery from Left Subclavian Vein

    Energy Technology Data Exchange (ETDEWEB)

    Lv, Tian-shi, E-mail: TerrenceLv@126.com; Wang, Chao, E-mail: wangchaoxs@163.com; Song, Li, E-mail: song9981@163.com; Lv, Yong-xing, E-mail: lyongxing@msn.com; Zou, Ying-hua, E-mail: yinghzou@139.com [Peking University First Hospital, Department of Interventional Radiology and Vascular Surgery (China)

    2013-10-15

    We report for the first time an extremely rare anomalous origin of the superior left pulmonary artery in a 60 year-old man. Although it was occult in clinical indications, such a malformation still ought to be considered, especially during endovascular procedures.

  18. Are Students Left Behind? The Distributional Effects of the No Child Left Behind Act

    Science.gov (United States)

    Krieg, John M.

    2008-01-01

    The No Child Left Behind Act imposes sanctions on schools if the fraction of students demonstrating proficiency on a high-stakes test falls below a statewide pass rate. While the motivation behind this system is improved public school performance, it also provides incentives for schools to focus educational resources on the marginal student rather…

  19. Left Hemisphere Regions Are Critical for Language in the Face of Early Left Focal Brain Injury

    Science.gov (United States)

    Beharelle, Anjali Raja; Dick, Anthony Steven; Josse, Goulven; Solodkin, Ana; Huttenlocher, Peter R.; Levine, Susan C.; Small, Steven L.

    2010-01-01

    A predominant theory regarding early stroke and its effect on language development, is that early left hemisphere lesions trigger compensatory processes that allow the right hemisphere to assume dominant language functions, and this is thought to underlie the near normal language development observed after early stroke. To test this theory, we…

  20. Left Inferior Frontal Cortex and Syntax: Function, Structure and Behaviour in Patients with Left Hemisphere Damage

    Science.gov (United States)

    Tyler, Lorraine K.; Marslen-Wilson, William D.; Randall, Billi; Wright, Paul; Devereux, Barry J.; Zhuang, Jie; Papoutsi, Marina; Stamatakis, Emmanuel A.

    2011-01-01

    For the past 150 years, neurobiological models of language have debated the role of key brain regions in language function. One consistently debated set of issues concern the role of the left inferior frontal gyrus in syntactic processing. Here we combine measures of functional activity, grey matter integrity and performance in patients with left…

  1. A new landing impact attenuation seat in manned spacecraft biologically-inspired by felids

    Directory of Open Access Journals (Sweden)

    Yu Hui

    2015-04-01

    Full Text Available When manned spacecraft comes back to the earth, it relies on the impact attenuation seat to protect astronauts from injuries during landing phase. Hence, the seat needs to transfer impact load, as small as possible, to the crew. However, there is little room left for traditional seat to improve further. Herein, a new seat system biologically-inspired by felids’ landing is proposed. Firstly, a series of experiments was carried out on cats and tigers, in which they were trained to jump down voluntarily from different heights. Based on the ground reaction forces combined with kinematics, the experiment indicated that felids’ landing after self-initial jump was a multi-step impact attenuation process and the new seat was inspired by this. Then the construction and work process of new seat were redesigned to realize the multi-step impact attenuation. The dynamic response of traditional and new seat is analyzed under the identical conditions and the results show that the new concept seat can significantly weaken the occupant overload in two directions compared with that of traditional seat. As a consequence, the risk of injury evaluated for spinal and head is also lowered, meaning a higher level of protection which is especially beneficial to the debilitated astronaut.

  2. Amplitudes for left-handed strings

    CERN Document Server

    Siegel, W

    2015-01-01

    We consider a class of string-like models introduced previously where all modes are left-handed, all states are massless, T-duality is manifest, and only a finite number of orders in the string tension can appear. These theories arise from standard string theories by a singular gauge limit and associated change in worldsheet boundary conditions. In this paper we show how to calculate amplitudes by using the gauge parameter as an infrared regulator. The amplitudes produce the Cachazo-He-Yuan delta-functions after some modular integration; the Mason-Skinner string-like action and amplitudes arise from the zero-tension (infinite-slope) limit. However, without the limit the amplitudes have the same problems as found in the Mason-Skinner formalism.

  3. Ablation therapy for left atrial autonomic modification.

    Science.gov (United States)

    Malcolme-Lawes, Louisa; Sandler, Belinda C; Sikkel, Markus B; Lim, Phang Boon; Kanagaratnam, Prapa

    2016-08-01

    The autonomic nervous system is implicated in the multifactorial pathogenesis of atrial fibrillation (AF) but few studies have attempted neural targeting for therapeutic intervention. We have demonstrated that short bursts of stimulation, at specific sites of left atrial ganglionated plexi (GPs), trigger fibrillation-inducing atrial ectopy and importantly continuous stimulation of these sites may not induce AV block, the 'conventional' marker used to locate GPs. We have shown that these ectopy-triggering GP (ET-GP) sites are anatomically stable and can be rendered inactive by either ablation at the site or by ablation between the site and the adjacent pulmonary vein (PV). This may have important implications for planning patient specific strategies for ablation of paroxysmal AF in the future. PMID:27595199

  4. Slow microwaves in left-handed materials

    Science.gov (United States)

    di Gennaro, E.; Parimi, P. V.; Lu, W. T.; Sridhar, S.; Derov, J. S.; Turchinetz, B.

    2005-07-01

    Remarkably slow propagation of microwaves in two different classes of left-handed materials (LHM’s) is reported from microwave-pulse and continuous-wave transmission measurements. Microwave dispersion in a composite LHM made of split-ring resonators and wire strips reveals group velocity vg˜c/50 , where c is the free-space light velocity. Photonic crystals (PhC’s) made of dielectric Al2O3 rods reveal vg˜c/10 . Group delay dispersion of both the composite LHM and PhC’s determined from the experiment is in complete agreement with that obtained from theory. The slow group velocities are quantitatively described by the strong dispersion observed in these materials.

  5. CT of left ventricular assist devices.

    Science.gov (United States)

    Carr, Carrie M; Jacob, Jaisy; Park, Soon J; Karon, Barry L; Williamson, Eric E; Araoz, Philip A

    2010-03-01

    Left ventricular assist devices (LVADs) have become an increasingly beneficial option for patients with heart failure, especially in light of the insufficient availability of donor hearts. LVADs have been used effectively in end-stage heart failure as a bridge to heart transplantation, as destination therapy for those ineligible for transplantation, or as a bridge to myocardial recovery. Presently, a wide variety of LVADs are being used therapeutically. Four different LVADs have been used at the authors' institution. The records of 42 patients who underwent implantation of 46 total LVADs during a 17-month period were reviewed; in 23 of these patients, computed tomography of the device was performed. Increased use of LVADs necessitates understanding of the normal positioning of a variety of these devices and recognition of potential complications, which include inflow and outflow cannula complications, postoperative hemorrhage, pericardial tamponade, thrombus formation, aortic valve stenosis, aortic valve insufficiency, right-sided heart failure, and infection. PMID:20228327

  6. A two phase harmonic model for left ventricular function

    CERN Document Server

    Dubi, S; Dubi, Y

    2006-01-01

    A minimal model for mechanical motion of the left ventricle is proposed. The model assumes the left ventricle to be a harmonic oscillator with two distinct phases, simulating the systolic and diastolic phases, at which both the amplitude and the elastic constant of the oscillator are different. Taking into account the pressure within the left ventricle, the model shows qualitative agreement with functional parameters of the left ventricle. The model allows for a natural explanation of heart failure with preserved systolic left ventricular function, also termed diastolic heart failure. Specifically, the rise in left ventricular filling pressures following increased left-ventricular wall stiffness is attributed to a mechanism aimed at preserving heart rate and cardiac output.

  7. A Class of Left E-adequate Semigroups

    Institute of Scientific and Technical Information of China (English)

    LI YONG-HUA; HE YONG

    2010-01-01

    In this paper we establish a construction of a class of left E-adequate semigroups by using semilattices of cancellative monoids and fundamental left E-adequate semigroups. We first introduce concepts of type μ+ (μ*, μ) abundant semigroups and type μ+ left E-adequate semigroups. In fact, regular semigroups are type μ+ abundant semigroups and inverse semigroups are type μ+ left E-adequate semigroups. Next, we construct a special kind of algebras called E+-product. It is proved that every E+-product is a type μ+ left E-adequate semigroup, and every type μ+ left E-adequate semigroup is isomorphic to an E+-product of a semilattice of cancellative monoids with a fundamental left E-adequate semigroup. Finally, as a corollary of the main result, it is deduced that every inverse semigroup is isomorphic to an E+-product of a Clifford semigroup by a fundamental inverse semigroup.

  8. Proprioceptive target matching asymmetries in left-handed individuals.

    Science.gov (United States)

    Goble, Daniel J; Noble, Brittany C; Brown, Susan H

    2009-08-01

    In right-handers, the ability to reproduce proprioceptive targets has been shown to be asymmetric, favoring the non-preferred left arm. The present study sought to determine whether a similar arm/hemisphere asymmetry exists for left-handers. Ten strong left-handed adults used the left or right arm to perform proprioceptive target matching tasks that varied in processing demands (i.e., need for memory, interhemispheric transfer) and target amplitude (20, 40 degrees). Similar to right-handers, left-handed individuals had smaller total errors when matching with the non-preferred arm. This asymmetry was greatest in conditions with increased processing demands and larger amplitude targets. These results provide the first evidence to date of right arm/left hemisphere dominance for proprioceptive target matching in left-handers that is the "mirror image" of right-handers.

  9. Melatonin attenuates hypertension-induced renal injury partially through inhibiting oxidative stress in rats.

    Science.gov (United States)

    Qiao, Yu-Feng; Guo, Wen-Juan; Li, Lu; Shao, Shan; Qiao, Xi; Shao, Jin-Jin; Zhang, Qiong; Li, Rong-Shan; Wang, Li-Hua

    2016-01-01

    The aim of the present study was to investigate the protective effects of melatonin (MLT) on hypertension-induced renal injury and identify its mechanism of action. Twenty-four healthy male Wistar rats were divided into a sham control group (n=8), which was subjected to sham operation and received vehicle treatment (physiological saline intraperitoneally at 0.1 ml/100 g), a vehicle group (n=8), which was subjected to occlusion of the left renal artery and vehicle treatment, and the MLT group (n=8), which was subjected to occlusion of the left renal artery and treated with MLT (10 mg/kg/day). Pathological features of the renal tissues were determined using hematoxylin and eosin staining and Masson staining. Urine protein, serum creatinine (Scr), superoxide dismutase (SOD) and malondialdehyde (MDA) were determined. Immunohistochemical analysis was performed to determine the expression of heme oxygenase‑1 (HO‑1), intercellular adhesion molecule‑1 (ICAM‑1), inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS). Furthermore, reverse transcription polymerase chain reaction was conducted to determine the mRNA expression of HO‑1, ICAM‑1, eNOS and iNOS. A marked decrease in blood pressure was noticed in the MLT group at week 4 compared with that of the vehicle group (Ptreatment attenuated the infiltration of inflammatory cells and oedema/atrophy of renal tubules. MLT attenuated hypertension-induced increases in urine protein excretion, serum creatinine and MDA as well as decreases in SOD activity in renal tissues. Furthermore, MLT attenuated hypertension-induced increases in iNOS and ICAM‑1 as well as decreases in eNOS and HO‑1 expression at the mRNA and protein level. In conclusion, the results of the present study indicated that MLT had protective roles in hypertension‑induced renal injury. Its mechanism of action is, at least in part, associated with the inhibition of oxidative stress. PMID:26531807

  10. Role of the hippocampus in sex differences in verbal memory: memory outcome following left anterior temporal lobectomy.

    Science.gov (United States)

    Berenbaum, S A; Baxter, L; Seidenberg, M; Hermann, B

    1997-10-01

    The authors examined the neural and cognitive bases for sex differences in verbal memory in 57 patients who underwent left anterior temporal lobectomy (ATL) for the treatment of intractable seizures. On the California Verbal Learning Test (D. C. Delis, J. H. Kramer, E. Kaplan, & B. A. Ober, 1987), women recalled more words than men both before and after surgery, regardless of the extent of hippocampal damage. Extent of hippocampal sclerosis was related to memory loss in both men and women. Women's superiority in verbal memory appears to result in part from their use of an efficient encoding strategy. Women were more likely than men to use semantic clustering both before and after ATL, and sex differences in word recall were attenuated after scores were adjusted for semantic clustering. There was no effect of ATL on semantic clustering. Taken together, these results suggest that sex differences in verbal memory are not due to differences in the integrity of the left hippocampus. PMID:9345702

  11. Localization of surface modes along a periodic/quasiperiodic structure containing a left-handed material

    Science.gov (United States)

    Toledo-Solano, M.; Palomino-Ovando, M. A.; Lozada-Morales, R.

    2015-12-01

    We have investigated the optical properties of a one-dimensional (1-D) photonic periodic/quasiperiodic structure, designed as photonic crystal (PC)-Fibonacci (FN)-photonic crystal (PC) sections. The structure is composed of alternating layers of a right-handed material (RHM) and a left-handed material (LHM). The RHM dielectric function is frequency independent and the LHM (metamaterial) dielectric function and magnetic susceptibility are described according to the Drude model. Using attenuated total reflectivity geometry, we explore the coupling of light with the plasmons on the surface of the metamaterial layers of the hybrid structure. The excitation of surface modes in different frequency regions are investigated. We observed bands of surface modes with a significant selective spatial localization at which the intensity of the electric field is confined almost totally within one of the PC sections or within the FN one.

  12. Breath-hold CT attenuation correction for quantitative cardiac SPECT

    OpenAIRE

    Koshino, Kazuhiro; Fukushima, Kazuhito; Fukumoto, Masaji; Sasaki, Kazunari; Moriguchi, Tetsuaki; Hori, Yuki; Zeniya, Tsutomu; Nishimura, Yoshihiro; Kiso, Keisuke; Iida, Hidehiro

    2012-01-01

    Background Attenuation correction of a single photon emission computed tomography (SPECT) image is possible using computed tomography (CT)-based attenuation maps with hybrid SPECT/CT. CT attenuation maps acquired during breath holding can be misaligned with SPECT, generating artifacts in the reconstructed images. The purpose of this study was to investigate the effects of respiratory phase during breath-hold CT acquisition on attenuation correction of cardiac SPECT imaging. Methods A series o...

  13. Frequency Dependence of Attenuation Constant of Dielectric Materials

    Directory of Open Access Journals (Sweden)

    A. S. Zadgaonkar

    1975-01-01

    Full Text Available Different dielectric materials have been studied for frequency dependence of attenuation constant. The sensitive cathode ray oscillograph method has been used to evaluate to the dielectric constant and loss factor, and from these attenuation constants have been calculated. The temperature remaining constant, a regular increase has been observed in attenuation constant, at higher frequencies of electro-magnetic propagating wave.

  14. Simple Scheme for Variable High Power Laser Beam Attenuation

    OpenAIRE

    Bialkowski, Stephen E.

    1987-01-01

    A venetian style infrared attenuator placed prior to a pinhole spatial filter results in variable high‐power laser attenuation. This attenuation scheme has a wide dynamic range, results in high‐quality Gaussian beams, does not introduce beam walk‐off error, and is independent of polarization.

  15. Attenuation of microwaves by poly-disperse small spheroid particles

    Science.gov (United States)

    Zhang, Peichang; Wang, Zhenhui

    1998-08-01

    Expressions for calculating the attenuation cross sections of poly-disperse, small spheroids, whose rotatory axes are in specific status, have been derived from a universal formula for calculating the attenuation cross section of a particle of arbitrary shape. Attenuation cross sections of liquid, ice, and spongy spheroidal droplets in different size and eccentricity at different wave lengths have been computed and analyzed.

  16. The Prognostic Value of Left Atrial Peak Reservoir Strain in Acute Myocardial Infarction Is Dependent on Left Ventricular Longitudinal Function and Left Atrial Size

    DEFF Research Database (Denmark)

    Ersbøll, Mads; Andersen, Mads J; Valeur, Nana;

    2013-01-01

    Peak atrial longitudinal strain (PALS) during the reservoir phase has been proposed as a measure of left atrium function in a range of cardiac conditions, with the potential for added pathophysiological insight and prognostic value. However, no studies have assessed the interrelation of PALS...... and left ventricular longitudinal strain (global longitudinal strain) in large-scale populations in regard to prognosis....

  17. Highly immunogenic variant of attenuated vaccinia virus.

    Science.gov (United States)

    Yakubitskyi, S N; Kolosova, I V; Maksyutov, R A; Shchelkunov, S N

    2016-01-01

    The LIVPΔ6 strain of vaccinia virus (VACV) was created by genetic engineering on the basis of previously obtained attenuated 1421ABJCN strain by target deletion of the A35R gene encoding an inhibitor of antigen presentation by the major histocompatibility complex class II. 1421ABJCN is the LIVP strain of VACV with five inactivated virulence genes encoding hemagglutinin (A56R), γ-interferon-binding protein (B8R), thymidine kinase (J2R), complement-binding protein (C3L), and Bcl2-like inhibitor of apoptosis (N1L). The highly immunogenic LIVPΔ6 strain could be an efficient fourth-generation attenuated vaccine against smallpox and other orthopoxvirus infections. PMID:27025484

  18. Carcinoma cervix with fat attenuating skull metastases

    Institute of Scientific and Technical Information of China (English)

    Anuradha Kapali; Atmakuri Sateesh Kumar; Mukunda Malathi; S D Shamsundar

    2016-01-01

    Skeletal metastasis in carcinoma cervix occurs in about 0.8-23% of cases. These lesions are usually radiographically lytic. Very few cases of metastases to the skull have been identiifed, about 5 cases to the best of our knowledge. We present a case of adenosquamous cell carcinoma of cervix with fat attenuating skull metastases in a 38-year-old lady that is not reported till date. The lesion was lytic, expansile and with negative attenuation of -15 to -30 Hounsifeld units corresponding to fat.Metastases must be included in the differentials of scalp lesions. A history of recent onset of swelling and associated lytic areas in calvarium on contrast enhanced computed tomography with multiplicity can give a clue to metastatic nature of disease.

  19. Particle size characterization by ultrasonic attenuation spectra

    Institute of Scientific and Technical Information of China (English)

    Mingxu Su; Minghua Xue; Xiaoshu Cai; Zhitao Shang; Feng Xu

    2008-01-01

    This paper contributes to extracting information from signals of broadband ultrasonic attenuation spectrum for effective utilization in particle size characterization. The single particle scattering model and the coupled-phase model are formulated simultaneously, the relationship between particle size distribution and ultrasonic spectrum is established, and a convergence criterion for calculation is quantified. Demonsa'ation inversion by the optimum regularization factor method is carded out to yield typical numerical results for discussion. With the experimental set-up developed by the Institute of Particle and Two-Phase Flow Measurement (IPTFM) at the University of Shanghai for Science and Technology, sand sediment particle size is measured by attenuation spectrum and analyzed using the above inversion algorithm and theoretical models. To validate the proposed ultrasonic spectrum particle sizing method, results are compared with those obtained by microscopy.

  20. Attenuation of gamma radiation in concrete shields

    International Nuclear Information System (INIS)

    The attenuation characteristics of γ radiation in concrete layers considering their mechanical resistence and densities were determined. A 137Cs source was used in a 'good geometry' arrangement to eliminate the effects of the buildup factor. The ordinary and the heavy concrete were irradiated and for the latter it was used as additives iron ore and Fe2O3 pellets in various grain sizes. The detection system consisted of a 2' x 2' NaI (Tl) crystal coupled to a photomultiplier tube and the associated electronic equipment. FORTRAN programs were used for determining the absorption coefficients and the attenuation factors. These programs calculate photopeak areas eliminating all contributions due to Compton effect and background. (Author)

  1. Clematichinenoside attenuates myocardial infarction in ischemia/reperfusion injury both in vivo and in vitro.

    Science.gov (United States)

    Zhang, Rui; Fang, Weirong; Han, Dan; Sha, Lan; Wei, Jie; Liu, Lifang; Li, Yunman

    2013-09-01

    Clematichinenoside is a triterpenoid saponin isolated from the roots of Clematis chinensis. Oxidative stress and excessive nitric oxide production are thought to play considerable roles in ischemia/reperfusion injury that impairs cardiac function. The present study investigated the protective effect of clematichinenoside on regional and global ischemia/reperfusion injury and ventricular myocytes. In vivo, regional myocardial ischemia/reperfusion injury of rats was induced by the occlusion of the left anterior descending coronary artery, and isolated guinea pigs heart using Langendorff apparatus served as a global ischemia/reperfusion injury model ex vivo. Primary cultured neonatal ventricular myocytes were further applied to explore the anti-ischemia/reperfusion injury property in vitro. Infarct size was measured with TTC stain; enzyme activities such as lactate dehydrogenase, creatine kinase, superoxide dismutase, malondialdehyde, and nitric oxide were analyzed with assay kits; inducible nitric oxide synthase and endothelial nitric oxide synthase expressions were determined by Western blot. Clematichinenoside attenuated infarct size, decreased lactate dehydrogenase, creatine kinase, and malondialdehyde levels and enhanced superoxide dismutase activity. Clematichinenoside improved hemodynamics indexes, such as left ventricular developed pressure, maximum left ventricular developed pressure, and increase/decrease rate (± dp/dtmax) in the isolated guinea pig heart after reperfusion. Clematichinenoside also inhibited excessive production of nitric oxide through downregulating inducible nitric oxide synthase as well as upregulating endothelial nitric oxide synthase during ischemia/reperfusion injury. Clematichinenoside attenuates ischemia/reperfusion injury in vivo, ex vivo, and in vitro via an antioxidant effect and by restoring the balance between inducible nitric oxide synthase and endothelial nitric oxide synthase. PMID:23929248

  2. Two-dimensional dynamic fluid bowtie attenuators.

    Science.gov (United States)

    Hermus, James R; Szczykutowicz, Timothy P

    2016-01-01

    Fluence field modulated (FFM) CT allows for improvements in image quality and dose reduction. To date, only one-dimensional modulators have been proposed, as the extension to two-dimensional (2-D) modulation is difficult with solid-metal attenuation-based fluence field modulated designs. This work proposes to use liquid and gas to attenuate the x-ray beam, as unlike solids, these materials can be arranged allowing for 2-D fluence modulation. The thickness of liquid and the pressure for a given path length of gas were determined that provided the same attenuation as 30 cm of soft tissue at 80, 100, 120, and 140 kV. Liquid iodine, zinc chloride, cerium chloride, erbium oxide, iron oxide, and gadolinium chloride were studied. Gaseous xenon, uranium hexafluoride, tungsten hexafluoride, and nickel tetracarbonyl were also studied. Additionally, we performed a proof-of-concept experiment using a 96 cell array in which the liquid thickness in each cell was adjusted manually. Liquid thickness varied as a function of kV and chemical composition, with erbium oxide allowing for the smallest thickness. For the gases, tungsten hexaflouride required the smallest pressure to compensate for 30 cm of soft tissue. The 96 cell iodine attenuator allowed for a reduction in both dynamic range to the detector and scatter-to-primary ratio. For both liquids and gases, when k-edges were located within the diagnostic energy range used for imaging, the mean beam energy exhibited the smallest change with compensation amount. The thickness of liquids and the gas pressure seem logistically implementable within the space constraints of C-arm-based cone beam CT (CBCT) and diagnostic CT systems. The gas pressures also seem logistically implementable within the space and tube loading constraints of CBCT and diagnostic CT systems. PMID:26835499

  3. Narrow terahertz attenuation signatures in Bacillus thuringiensis.

    Science.gov (United States)

    Zhang, Weidong; Brown, Elliott R; Viveros, Leamon; Burris, Kellie P; Stewart, C Neal

    2014-10-01

    Terahertz absorption signatures from culture-cultivated Bacillus thuringiensis were measured with a THz photomixing spectrometer operating from 400 to 1200 GHz. We observe two distinct signatures centered at ∼955 and 1015 GHz, and attribute them to the optically coupled particle vibrational resonance (surface phonon-polariton) of Bacillus spores. This demonstrates the potential of the THz attenuation signatures as "fingerprints" for label-free biomolecular detection. PMID:23821459

  4. The attenuation coefficients in CT: Didactic review

    International Nuclear Information System (INIS)

    The review article refers details about the derivation of the Attenuation coefficient of the CT-Number, the electron density and physical density, the effective atomic number, dual KV scanning, the performance of different scanners, furtheron the CT-numbers of intracranial structures, the attempts of characterization of tissue by CT, measurements of effective atomic number and electron density, distribution and probability of occurance of CT-numbers, and distribution of CT-numbers in space. (AJ)

  5. Bubbles attenuate elastic waves at seismic frequencies

    Science.gov (United States)

    Tisato, Nicola; Quintal, Beatriz; Chapman, Samuel; Podladchikov, Yury; Burg, Jean-Pierre

    2016-04-01

    The vertical migration of multiphase fluids in the crust can cause hazardous events such as eruptions, explosions, pollution and earthquakes. Although seismic tomography could potentially provide a detailed image of such fluid-saturated regions, the interpretation of the tomographic signals is often controversial and fails in providing a conclusive map of the subsurface saturation. Seismic tomography should be improved considering seismic wave attenuation (1/Q) and the dispersive elastic moduli which allow accounting for the energy lost by the propagating elastic wave. In particular, in saturated media a significant portion of the energy carried by the propagating wave is dissipated by the wave-induced-fluid-flow and the wave-induced-gas-exsolution-dissolution (WIGED) mechanisms. The WIGED mechanism describes how a propagating wave modifies the thermodynamic equillibrium between different fluid phases causing the exsolution and the dissolution of the gas in the liquid, which in turn causes a significant frequency dependent 1/Q and moduli dispersion. The WIGED theory was initially postulated for bubbly magmas but only recently was extended to bubbly water and experimentally demonstrated. Here we report these theory and laboratory experiments. Specifically, we present i) attenuation measurements performed by means of the Broad Band Attenuation Vessel on porous media saturated with water and different gases, and ii) numerical experiments validating the laboratory observations. Finally, we will extend the theory to fluids and to pressure-temperature conditions which are typical of phreatomagmatic and hydrocarbon domains and we will compare the propagation of seismic waves in bubble-free and bubble-bearing subsurface domains. With the present contribution we extend the knowledge about attenuation in rocks which are saturated with multiphase fluid demonstrating that the WIGED mechanism could be extremely important to image subsurface gas plumes.

  6. Phonic Attenuation due to Screen-Barriers

    OpenAIRE

    Vasile Bacria; Nicolae Herişanu

    2011-01-01

    The technique of noise decreasing admits two basic approaches: an active approach and a passive one. In the frame of passive method one can count the employment of screen-barriers. In this paper we present some considerations on sound attenuation due to screen-barriers emphasizing the elements which influence it. The elucidation of these elements is made by measurements. The obtained results can be applied in every other practical situation concerning the protection against ...

  7. Narrow terahertz attenuation signatures in Bacillus thuringiensis.

    Science.gov (United States)

    Zhang, Weidong; Brown, Elliott R; Viveros, Leamon; Burris, Kellie P; Stewart, C Neal

    2014-10-01

    Terahertz absorption signatures from culture-cultivated Bacillus thuringiensis were measured with a THz photomixing spectrometer operating from 400 to 1200 GHz. We observe two distinct signatures centered at ∼955 and 1015 GHz, and attribute them to the optically coupled particle vibrational resonance (surface phonon-polariton) of Bacillus spores. This demonstrates the potential of the THz attenuation signatures as "fingerprints" for label-free biomolecular detection.

  8. LCLS XTOD Attenuator System System Concept Report

    Energy Technology Data Exchange (ETDEWEB)

    Kishiyama, K; Roeben, M; Trent, J; Ryutov, D; Shen, S

    2006-04-12

    The attenuator system for the Linac Coherent Light Source (LCLS) X-ray Transport, Optics and Diagnostics (XTOD) system has been configured and analyzed by the Lawrence Livermore National Laboratory's New Technologies Engineering Division (NTED) as requested by the SLAC/LCLS program. The system layout, performance analyses and selection of the vacuum components are presented in this System Conceptual Review (SCR) report. Also included are the plans for prototype, procurement, mechanical integration, and the cost estimates.

  9. Attenuated Measles Virus as a Vaccine Vector

    OpenAIRE

    Zuniga, Armando; Wang, Zili; Liniger, Matthias; Hangartner, Lars; Caballero, Michael; Pavlovic, Jovan; Wild, Peter; Viret, Jean Francois; Glueck, Reinhard; Billeter, Martin A.; Naim, Hussein Y.

    2007-01-01

    Live attenuated measles virus (MV) vaccines have an impressive record of safety, efficacy and ability to induce life-long immunity against measles infection. Using reverse genetics technology, such negative-strand RNA viruses can now be rescued from cloned DNA. This technology allows the insertion of exogenous genes encoding foreign antigens into the MV genome in such a way that they can be expressed by the MV vaccine strain, without affecting virus structure, propagation and cell targeting. ...

  10. Lg Attenuation of the Western United States

    Science.gov (United States)

    Gallegos, A. C.; Ranasinghe, N. R.; Ni, J.; Sandvol, E. A.

    2014-12-01

    Lg waveforms recorded by EarthScope's Transportable Array (TA) are used to estimate Lg Q in the Western United States (WUS). Attenuation is calculated based on Lg spectral amplitudes filtered at a narrow band from 0.5 to 1.5 Hz with a central frequency of 1 Hz. The two-station and reverse two-station techniques were used to calculate Qo values. 398 events occurring from 2005 to 2009 and ranging from magnitude 3 to magnitude 6 were used in this study. The geometric spreading term can be determined by using a three-dimensional linear fit of the amplitude ratios versus epicentral distances to two stations. The slope of this line provides the geometric spreading term we use to calculate Lg Qo values of WUS. The results show high Q regions (low attenuation) corresponding to the Colorado Plateau (CP), the Rocky Mountains (RM), the Columbia Plateau (COP), and the Sierra Nevada Mountains (SNM). Regions of low Q (high attenuation) are seen along the Snake River Plain (SRP), the Rio Grande Rift (RGR), the Cascade Mountains (CM), and in east and west of the Basin and Range (BR) where tectonic activity is more active than the central part of the BR. A positive correlation between high heat flow, recent tectonic activity and Q was observed. Areas with low heat flow, thin sediment cover, and no recent tectonic activity were observed to have consistently high Q. These new models use two-station and reversed two-station methods and provide a comparison with previous studies and better constrain regions with high attenuation. This increase in detail can improve high frequency ground motion predictions of future large earthquakes for more accurate hazard assessment and improve overall understanding of the structure and assemblage of the WUS.

  11. The Violent Content in Attenuated Psychotic Symptoms.

    Science.gov (United States)

    Marshall, Catherine; Deighton, Stephanie; Cadenhead, Kristin S; Cannon, Tyrone D; Cornblatt, Barbara A; McGlashan, Thomas H; Perkins, Diana O; Seidman, Larry J; Tsuang, Ming T; Walker, Elaine F; Woods, Scott W; Bearden, Carrie E; Mathalon, Daniel; Addington, Jean

    2016-08-30

    The relationship between psychosis and violence has typically focused on factors likely to predict who will commit violent acts. One unexplored area is violence in the content of subthreshold positive symptoms. The current aim was to conduct an exploratory analysis of violent content in the attenuated psychotic symptoms (APS) of those at clinical high risk of psychosis (CHR) who met criteria for attenuated psychotic symptom syndrome (APSS). The APS of 442 CHR individuals, determined by the Structured Interview for Prodromal Syndromes, were described in comprehensive vignettes. The content of these symptoms were coded using the Content of Attenuated Positive Symptoms Codebook. Other measures included clinical symptoms, functioning, beliefs and trauma. Individuals with violent content had significantly higher APS, greater negative beliefs about the self and others, and increased bullying. The same findings and higher ratings on anxiety symptoms were present when participants with self-directed violence were compared to participants with no violent content. Individuals reporting violent content differ in their clinical presentation compared to those who do not experience violent content. Adverse life events, like bullying, may impact the presence of violent content in APS symptoms. Future studies should explore violent content in relation to actual behavior. PMID:27259137

  12. Natural Biological Attenuation of Benzene in Groundwater

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Benzene has been found in subsurface unsaturated soil and groundwater beneath a petro-chemical plant. Although the groundwater contained several mg/L of benzene in the area immediately beneath the source, benzene was not detected in monitoring wells approximately 800m down stream. All kinds of physical processes such as adsorption and advection/dispersion are considered to account for the observed attenuation. The results indicated that the attenuation was primarily due to natural biological processes occurring within the aquifer. The evidence for the natural bioremediation of benzene from the groundwater included: (1) analysis of groundwater chemistry, (2) laboratory studies demonstrating benzene biodegradation in aquifer samples, and (3) computer simulations examining benzene transport. Laboratory experiments indicated that for conditions similar to those in the plume, the aerobic degradation of benzene by the naturally occurring microorganisms in the polluted groundwater samples was quite rapid with a half-life time of from 5 to 15 days. In situ analyses indicated the level of dissolved oxygen in the groundwater was over 2mg/L. Thus, oxygen should not limit the biodegradation. In fact, the benzene was also shown to degrade under anaerobic conditions. The results from the modeling simulations indicate that biodegradation is the dominant process influencing attenuation of the benzene.

  13. Waves in fragmented geomaterials with impact attenuation

    Science.gov (United States)

    Dyskin, Arcady; Pasternak, Elena

    2016-04-01

    Attenuation of waves in geomaterials, such as seismic waves is usually attributed to energy dissipation due to the presence of viscous fluid and/or viscous cement between the constituents. In fragmented geomaterials such as blocky rock mass there is another possible source of energy dissipation - impacting between the fragments. This can be characterised by the coefficient of restitution, which is the ratio between the rotational velocities after and before the impact. In particular, this manifests itself in the process of mutual rotations of the fragments/blocks, whereby in the process of oscillation different ends of the contacting faces of the fragments are impacting. During the rotational oscillations the energy dissipation is concentrated in the neutral position that is the one in which the relative rotation between two fragments is zero. We show that in a simple system of two fragments this dissipation is equivalent, in a long run, to the presence of viscous damper between the fragments (the Voigt model of visco-elasticity). Generalisation of this concept to the material consisting of many fragments leads to a Voigt model of wave propagation where the attenuation coefficient is proportional to the logarithm of restitution coefficient. The waves in such a medium show slight dispersion caused by damping and strong dependence of the attenuation on the wave frequency.

  14. Novel Intriguing Strategies Attenuating to Sarcopenia

    Directory of Open Access Journals (Sweden)

    Kunihiro Sakuma

    2012-01-01

    Full Text Available Sarcopenia, the age-related loss of skeletal muscle mass, is characterized by a deterioration of muscle quantity and quality leading to a gradual slowing of movement, a decline in strength and power, increased risk of fall-related injury, and, often, frailty. Since sarcopenia is largely attributed to various molecular mediators affecting fiber size, mitochondrial homeostasis, and apoptosis, the mechanisms responsible for these deleterious changes present numerous therapeutic targets for drug discovery. Resistance training combined with amino acid-containing supplements is often utilized to prevent age-related muscle wasting and weakness. In this review, we summarize more recent therapeutic strategies (myostatin or proteasome inhibition, supplementation with eicosapentaenoic acid (EPA or ursolic acid, etc. for counteracting sarcopenia. Myostatin inhibitor is the most advanced research with a Phase I/II trial in muscular dystrophy but does not try the possibility for attenuating sarcopenia. EPA and ursolic acid seem to be effective as therapeutic agents, because they attenuate the degenerative symptoms of muscular dystrophy and cachexic muscle. The activation of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α in skeletal muscle by exercise and/or unknown supplementation would be an intriguing approach to attenuating sarcopenia. In contrast, muscle loss with age may not be influenced positively by treatment with a proteasome inhibitor or antioxidant.

  15. Soil mass attenuation coefficient: Analysis and evaluation

    International Nuclear Information System (INIS)

    Highlights: • Experimental mass attenuation coefficient is affected by sample size. • Sample thickness larger than 9 cm presents the best results for 137Cs. • Sample thickness smaller than 5 cm presents the best results for 241Am. - Abstract: The mass attenuation coefficient (μ) is an important parameter to characterize the penetration and interaction of gamma-rays in the soil. Accurate determinations of μ are important to obtain representative values of soil physical properties by gamma-ray attenuation technique. In this study, the effect of collimator size (2–4 mm diameters) and absorber thickness (2–15 cm) on the experimental μ values of water and soils with different textures were investigated for 59.54 keV (241Am) and 661.1 keV (137Cs) gamma-ray sources. Theoretical results were calculated using the program XCOM. Experimental results were compared with theoretical ones showing a good correlation between methods. It was observed that for the 137Cs the best agreements between theoretical and experimental μ were obtained for sample thickness ⩾10 cm while for the 241Am were those obtained for thickness <5 cm for small collimators

  16. Novel parameter for assessment of left atrial size in patients with hypertension: ratio of left atrial volume to left ventricular volume

    Institute of Scientific and Technical Information of China (English)

    LI Yue; CHAI Liang; ZHANG Yun; LI Lei

    2009-01-01

    Background Left atrial enlargement has been suggested as a more robust marker of diastolic dysfunction. We hypothesize that the ratio of left atrial volume to left ventricular volume (LAV/LVV) may be more reasonable to reflect left atrial enlargement in the patients with hypertension, because hypertensive patients have a characteristic of concentric remodeling of the left ventricle which is often accompanied with diastolic dysfunction. The aim of this study was to determine if the LAV/LVV can be used as a new parameter to assess left atrial size in hypertensive patients and the relationship between the LAV/LVV and diastolic dysfunction.Methods Ninety-one patients with hypertension and forty-three normal controls were studied. The hypertensive patients were assigned to the normal wall (NW) and hypertrophic wall (HW) groups. The left atrial diameter (LAD), LAV, left atrial volume index (LAVi), LVV and LAV/LVV were measured and calculated by 2-dimensional echocardiography and real time 3-dimensional echocardiography. All of the above parameters were used to evaluate the size of the left atrium. The ratio of peak E velocity of mitral valve inflow to peak E' velocity of lateral mitral annulus (E/E') was measured by pulse Doppler and tissue Doppler. This parameter was used to evaluate diastolic function. Results The LAD, LAV, LAVi, LAV/LVV and E/E' in hypertensive groups were significantly higher than those in the normal group (P <0.05 or 0.01), and those in the HW group were significantly higher than those in the NW group (P <0.05 or 0.01). The E/E' had a positive correlation with LAV, LAVi and LAV/LVV. The correlation coefficient between E/E' and LAV/LVV was relatively higher than that between E/E' and LAD or LAVi.Conclusion LAV/LVV may be used as a new index to evaluate left atrial size in hypertensive patients with diastolic dysfunction.

  17. Totally endoscopic robotic resection of left atrial myxoma with persistent left superior vena cava.

    Science.gov (United States)

    Tarui, Tatsuya; Ishikawa, Norihiko; Ohtake, Hiroshi; Watanabe, Go

    2016-07-01

    A 68-year old man with a cardiac tumour was admitted for robotic tumour resection using the da Vinci S Surgical System. While undergoing preoperative examination, he was found to have a persistent left superior vena cava. After general anaesthesia and single-lung ventilation, cardiopulmonary bypass was established, with venous drainage through bilateral internal jugular and right femoral veins and arterial return through the right femoral artery. Robotic tumour resection was performed by four ports in the right chest. There were no difficulties during the operation, and successful tumour resection was achieved with satisfactory margins. He was discharged without complications. Persistent left superior vena cava is very rare, but if diagnosed preoperatively and an appropriate operative plan is made, robotic cardiac surgery can be performed safely. With robotic surgery, cardiac tumour resection can be feasibly performed, with cosmetic benefits. PMID:26989070

  18. Left Ventricular Hypertrophy Evaluation in Obese Hypertensive Patients: Effect of Left Ventricular Mass Index Criteria

    Directory of Open Access Journals (Sweden)

    Eduardo Cantoni Rosa

    2002-04-01

    Full Text Available PURPOSE: To evaluate left ventricular mass (LVM index in hypertensive and normotensive obese individuals. METHODS: Using M mode echocardiography, 544 essential hypertensive and 106 normotensive patients were evaluated, and LVM was indexed for body surface area (LVM/BSA and for height² (LVM/h². The 2 indexes were then compared in both populations, in subgroups stratified according to body mass index (BMI: or = 30kg/m². RESULTS: The BSA index does not allow identification of significant differences between BMI subgroups. Indexing by height² provides significantly increased values for high BMI subgroups in normotensive and hypertensive populations. CONCLUSION: Left ventricular hypertrophy (LVH has been underestimated in the obese with the use of LVM/BSA because this index considers obesity as a physiological variable. Indexing by height² allows differences between BMI subgroups to become apparent and seems to be more appropriate for detecting LVH in obese populations.

  19. Congenital left ventricular aneurysm coexisting with left ventricular non-compaction in a newborn.

    Science.gov (United States)

    Ootani, Katsuki; Shimada, Jun; Kitagawa, Yosuke; Konno, Yuki; Miura, Fumitake; Takahashi, Toru; Ito, Etsuro; Ichinose, Kouta; Yonesaka, Susumu

    2014-10-01

    Described herein is the case of a rare combination of congenital left ventricular (LV) aneurysm and left ventricular non-compaction (LVNC) in a newborn. The patient developed refractory heart failure soon after birth and died at 5 months of age. The etiology of both congenital LV aneurysm and LVNC seems to be maldevelopment of the ventricular myocardium during early fetal life. Treatment should be individually tailored depending on clinical severity, and treatment options are limited. Given that this combination of congenital LV aneurysm and LVNC is significantly associated with poor prognosis, it appears that patients with congenital LV aneurysm and LVNC are candidates for early, aggressive intervention, including surgical aneurysmectomy and evaluation for transplantation. It is important to be aware of this combination of congenital LV aneurysm and LVNC, and to make earlier decisions on therapeutic strategy.

  20. Seismic Attenuation Inversion with t* Using tstarTomog.

    Energy Technology Data Exchange (ETDEWEB)

    Preston, Leiph

    2014-09-01

    Seismic attenuation is defined as the loss of the seismic wave amplitude as the wave propagates excluding losses strictly due to geometric spreading. Information gleaned from seismic waves can be utilized to solve for the attenuation properties of the earth. One method of solving for earth attenuation properties is called t*. This report will start by introducing the basic theory behind t* and delve into inverse theory as it pertains to how the algorithm called tstarTomog inverts for attenuation properties using t* observations. This report also describes how to use the tstarTomog package to go from observed data to a 3-D model of attenuation structure in the earth.

  1. Are all left supraclavicular lymphadenopathies Virchow's? A retrospective study of 320 left cervical lymphadenopathy

    OpenAIRE

    Veena Raja; Chinnaiya Subramaniam; Babu Rajendra Prasad; Mari Lingiah Harendra Kumar; Balluru Vasudeva Swaroop Raj

    2016-01-01

    Background: Cervical Lymphadenopathy is one of the commonest and sometimes only clinical finding for a benign and malignant lesion. Fine needle aspiration cytology (FNAC) is a simple, safe, rapid and inexpensive method for establishing the diagnosis of lesions. Metastasis is more common in cervical lymph node and enlarged cervical nodes in an elderly patient must be considered as metastatic until proved otherwise. Methods: Retrospectively, 320 cases of left cervical lymph node FNAC were colle...

  2. Intradural herniation of a thoracic disc presenting as left radicular pain and left drop foot

    Directory of Open Access Journals (Sweden)

    Takuji Matsumoto

    2015-09-01

    Full Text Available Intradural disc herniation is a rare pathological entity. Normally, it is associated with severe neurological deficits, including compression syndrome of the spinal cord or cauda equina. Intradural disc herniations comprise 0.26% to 030% of all herniated discs. Overall, 5% are found in the thoracic region, 3% in the cervical region, and 92% in the lumbar region. Although intradural disc herniation may be suspected preoperatively because of myelography, computed tomography, and magnetic resonance imaging results, establishing the diagnosis before surgery is difficult. We report a patient with thoracic intradural disc herniation at T11-12 who presented with left radicular pain and left drop foot. Preoperative magnetic resonance imaging, computed tomography, and myelography failed to demonstrate an intradural lesion. The patient underwent T11-L1 dorsal hemilaminectomy with lateral extension to the left side. The herniation was identified only intraoperatively during inspection of the thecal sac. The disc was removed surgically, and the operation was performed safely under intraoperative spinal cord monitoring. The patient had a good neurological recovery. She remains pain-free 2 years after the surgery.

  3. Arterial baroreflex function and left ventricular hypertrophy

    Institute of Scientific and Technical Information of China (English)

    MIAO Chao-Yu; SU Ding-Feng

    2004-01-01

    It is well known that the arterial baroreflex(ABR)plays a key role in the regulation of heart rate and stabilization of blood pressure.Currently,it appears that ABR dysfunction is involved in the pathophysiology of cardiovascular disease states.Since the mid-1990s,a number of studies have been carried out in our laboratory to explore the pathological significance of ABR function in cardiovascular damage.This minireview summarizes our research work on the topic of ABR and left ventricular hypertrophy(LVH).On the basis of discussion concerning the importance of ABR dysfunction in hypertensive LVH and sinoaortic denervation-induced LVH,we advance a new strategy for reversal of LVH,that is,restoration of impaired ABR function.We tested this hypothesis in animal models with ABR deficiency.It was found that improvement of impaird ABR function with long-term treatment of ketanserin or candesartan was accompanied by reversal of LVH.The preliminary results indicate that it is feasible to target ABR for treatment of LVH.

  4. What's 'left' in the 'Garden of Sweden'?

    Science.gov (United States)

    Olsen, Gregg M

    2013-01-01

    Liberalization, restructuring, and retrenchment have been underway in Sweden for more than two decades and have rapidly accelerated under the current non-socialist coalition government. It is uncertain how much of the Swedish social policy model is "left" now, in terms of both what remains of it and its political character. A cross-temporal look at developments within Sweden reveals striking and continual rollbacks and marketization since the 1990s. However, this view must be qualified, both because Sweden's undisputed descent is from a comparatively lofty position and because there have been some noteworthy, but often ignored, gains even amidst marked decline over the past few decades. A cross-national examination indicates that, despite rapidly rising rates of income and wealth inequality, Sweden remains an egalitarian leader in several respects. This view must be qualified, too, because, while it continues to routinely out-perform Anglo nations such as Canada, the United Kingdom, and the United States, Sweden is less often, and less notably, distinct from several of its continental counterparts in Europe now. Moreover, the foundation of the model, labor strength, has been significantly undermined. PMID:23527451

  5. What's 'left' in the 'Garden of Sweden'?

    Science.gov (United States)

    Olsen, Gregg M

    2013-01-01

    Liberalization, restructuring, and retrenchment have been underway in Sweden for more than two decades and have rapidly accelerated under the current non-socialist coalition government. It is uncertain how much of the Swedish social policy model is "left" now, in terms of both what remains of it and its political character. A cross-temporal look at developments within Sweden reveals striking and continual rollbacks and marketization since the 1990s. However, this view must be qualified, both because Sweden's undisputed descent is from a comparatively lofty position and because there have been some noteworthy, but often ignored, gains even amidst marked decline over the past few decades. A cross-national examination indicates that, despite rapidly rising rates of income and wealth inequality, Sweden remains an egalitarian leader in several respects. This view must be qualified, too, because, while it continues to routinely out-perform Anglo nations such as Canada, the United Kingdom, and the United States, Sweden is less often, and less notably, distinct from several of its continental counterparts in Europe now. Moreover, the foundation of the model, labor strength, has been significantly undermined.

  6. ECG manifestations of left ventricular electrical remodeling.

    Science.gov (United States)

    Estes, E Harvey

    2012-01-01

    Research and thinking about the electrocardiographic manifestations of left ventricular hypertrophy has been constrained by a limited conceptual model of the process: heart disease produces chamber enlargement (increased mass), which in turn produces an altered electrocardiogram. The process is much more complex than can be represented in this simple model. A more robust and intricate model is proposed, in which heart (and vascular) disease causes structural changes, electrical changes, biochemical changes, and others, all of which interact to produce electrical remodeling of ventricular myocardium. This electrical remodeling results in a variety of ECG changes. All of these changes interact, leading to an altered clinical course, and to premature death. It is suggested that research, based on this model, can provide new clues to the processes involved, and improve the prediction of clinical outcomes. New directions in research, in recording equipment, and in organizational activities are suggested to test this new model, and to improve the usefulness of the electrocardiogram as a research and diagnostic tool.

  7. TOOL USE DISORDERS AFTER LEFT BRAIN DAMAGE

    Directory of Open Access Journals (Sweden)

    Josselin eBaumard

    2014-05-01

    Full Text Available In this paper we review studies that investigated tool use disorders in left-brain damaged (LBD patients over the last thirty years. Four tasks are classically used in the field of apraxia: Pantomime of tool use, single tool use, real tool use and mechanical problem solving. Our aim was to address two issues, namely, (1 the role of mechanical knowledge in real tool use and (2 the cognitive mechanisms underlying pantomime of tool use, a task widely employed by clinicians and researchers. To do so, we extracted data from 36 papers and computed the difference between healthy subjects and LBD patients. On the whole, pantomime of tool use is the most difficult task and real tool use is the easiest one. Moreover, associations seem to appear between pantomime of tool use, real tool use and mechanical problem solving. These results suggest that the loss of mechanical knowledge is critical in LBD patients, even if all of those tasks (and particularly pantomime of tool use might put differential demands on semantic memory and working memory.

  8. Left ventricular noncompaction: Clinical-echocardiographic study

    Directory of Open Access Journals (Sweden)

    Nikolić Aleksandra

    2012-01-01

    Full Text Available Background/Aim. Left ventricular noncompaction (LVNC is a disorder in endomyocardial morphogenesis, seen either isolated (in the absence of other cardiac anomalies or in association with congenital heart disease and some neuromuscular diseases. Intrauterine arrest of the compaction of myocardial fibers is postulated to be the reason of LVNC. Recognition of this condition is extremely important due to its high mortality and morbidity that lead to progressive heart failure, ventricular arrhythmias and thromboembolic events. The aim of this study was to determine the prevalence and clinical presentation of LVNC among consecutive outpatients according to clinical and echocardiographyic findings. Methode. A total of 3,854 consecutive patients examined at the Institute for Cardiovascular Diseases within a period January 2006 - January 2007 were included in the study. All the patients underwent echocardiographic examination using the same equipment (Vivid 7, GE Medical System. Echocardiographic parameters and clinical presentation in patients with echocardiographic criteria for LVNC were analyzed. Results. Analyzing 3,854 consecutive outpatients, using two-dimensional Color Doppler echocardiography from January 2006 to January 2007, 12 patients met the criteria for LVNC. Seven of them were male. The mean age at diagnosis was 45 ± 15 years. Analyzing clinical manifestation of LVNC it was found that seven patients had signs of heart failure, six had arrhythmias with no embolic events. Conclusion. Our results suggest that the real prevalence of LVNC may be higher than expected. New studies have to be done to solve this problem.

  9. Determination of the attenuation map in emission tomography

    CERN Document Server

    Zaidi, H

    2002-01-01

    Reliable attenuation correction methods for quantitative emission computed tomography (ECT) require accurate delineation of the body contour and often necessitate knowledge of internal anatomical structure. Two broad classes of methods have been used to calculate the attenuation map referred to as "transmissionless" and transmission-based attenuation correction techniques. While calculated attenuation correction belonging to the first class of methods is appropriate for brain studies, more adequate methods must be performed in clinical applications where the attenuation coefficient distribution is not known a priori, and for areas of inhomogeneous attenuation such as the chest. Measured attenuation correction overcomes this problem and utilizes different approaches to determine this map including transmission scanning, segmented magnetic resonance images or appropriately scaled X-ray CT scans acquired either independently on separate or simultaneously on multimodality imaging systems. Combination of data acqu...

  10. Isolated Left Pulmonary Artery Agenesis: A Case Report

    Directory of Open Access Journals (Sweden)

    Tansel Ansal Balcı

    2012-08-01

    Full Text Available Unilateral pulmonary artery agenesis without any cardiovascular malformation is a rare anomaly. We present the imaging findings of a patient who was diagnosed as isolated left pulmonary artery agenesis. A 27-year-old female patient was admitted to our hospital due to dyspnea during exercise for five years. Chest X-ray revealed minimally small left pulmonary hilum and left lung. She was admitted to our clinic with the suspicion of pulmonary artery pathology. Absent perfusion of the left lung with normal ventilation was visualized on scintigraphy. MDCT angiography of pulmonary arteries showed absent left main pulmonary artery with systemic collaterals around left hemithorax. Pulmonary artery agenesis can be asymptomatic and isolated until adulthood. Both scintigraphy and CT angiography images of pulmonary artery agenesis of a patient are rare in the literature. Pulmonary ventilation- perfusion scintigraphy can be used not only for pulmonary embolism but also pathologies involving pulmonary artery and its branches. (MIRT 2012;21:80-83

  11. Stopband Phenomena in the Passband of Left-Handed Metamaterials

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xiao-Peng; ZHAO Qian; ZHANG Fu-Li; ZHAO Wei; LIU Ya-Hong

    2006-01-01

    Stopband phenomena are reported in the passband of left-handed metamaterials. The samples with linear defect are designed by removing one layer of split ring resonators (SRRs). It is shown that the left-handed transmission peaks have a distinct transform with the relative deviation of the SRRs centre from the wire centre δ, from a single left-handed peak, double left-handed peaks with different magnitude to no transmission peak, i.e. left-handed properties of metamaterials disappear. Numerical simulation shows that the change of δ makes the effective permeability shift at a frequency range, where stopband occurs. It is thought that the stopband in left-handed passband is due to the symmetry breaking between SRRs and wires in the metamaterials.

  12. Atypical interhemispheric communication in left-handed individuals.

    Science.gov (United States)

    Iwabuchi, Sarina J; Kirk, Ian J

    2009-01-28

    The relative latencies of evoked electroencephalogram potentials to lateralized visual stimuli were used to calculate the interhemispheric transfer time (IHTT) in right-handed and left-handed males. We confirmed earlier observations of a directional asymmetry in right-handed males. That is, IHTT from the right to the left hemisphere is significantly shorter than from the left to the right. We showed for the first time, however, that this directional asymmetry is not seen in left-handed males. It is suggested that differences in the cytoarchitechtonics of the right and left hemisphere (differences that may result in lateralization of function per se) underlie the asymmetric IHTT in right handers, and that these differences are less pronounced in left handers.

  13. Left ventricular geometry and white matter lesions in ischemic stroke patients.

    Science.gov (United States)

    Butenaerts, Demian; Chrzanowska-Wasko, Joanna; Slowik, Agnieszka; Dziedzic, Tomasz

    2016-06-01

    Abnormal left ventricular (LV) geometry is associated with extracardiac organ damage in patients with hypertension. The aim of this study was to determine the relationship between LV geometry and white matter lesions (WMLs) in ischemic stroke patients. We retrospectively analyzed data from 155 patients (median age 62; 49.8% male) with mild ischemic stroke (median National Institutes of Health Stroke Scale score 4) who underwent brain magnetic resonance imaging and echocardiography. Patients were categorized into four groups: normal LV geometry, concentric remodeling, eccentric left ventricular hypertrophy (LVH) and concentric LVH. WMLs were graded using the Fazekas scale on fluid-attenuated inversion recovery images. Extensive WMLs were defined as a Fazekas score > 2. Extensive WMLs were more prevalent in patients with concentric LVH, eccentric LVH and concentric remodeling than in those with normal LV geometry. After adjusting for hypertension, age, diabetes mellitus, hypercholesterolemia, glomerular filtration rate and ischemic heart disease, patients with concentric remodeling [odds ratio (OR) 3.94, 95% confidence interval (CI) 1.26-12.31, p = 0.02] and those with concentric LVH (OR 3.69, 95% CI 1.24-10.95, p = 0.02), but not patients with eccentric LVH (OR 2.44, 95% CI 0.72-8.29, p = 0.15), had higher risk of extensive WMLs than patients with normal LV geometry. PMID:26581453

  14. Visual asymmetry revisited: Mind wandering preferentially disrupts processing in the left visual field.

    Science.gov (United States)

    Kam, Julia W Y; Nagamatsu, Lindsay S; Handy, Todd C

    2014-10-29

    An emerging theory proposes that visual attention operates in parallel at two distinct time scales - a shorter one (10s) associated with more global aspects of attention-to-task. Given their parallel nature, here we examined whether these comparatively slower fluctuations in task-related attention show the same visual field asymmetry - namely, a right visual field bias - as often reported for selective visual-spatial attention. Participants performed a target detection task at fixation while event-related potentials (ERP) time-locked to task-irrelevant visual probes presented in the left and right visual fields were recorded. At random intervals, participants were asked to report whether they were "on-task" or "mind wandering". Our results demonstrated that sensory attenuation during periods of "mind wandering" relative to "on-task", as measured by the visual P1 ERP component at electrodes sites contralateral to the stimulus, was only observed for probes presented in the left visual field. In contrast, the magnitude of sensory gain in the right visual field was insensitive to whether participants were "on-task" or "mind wandering". Taken together, our results support the notion that task-related attention at longer time scales and spatial attention at shorter time scales affect the same underlying mechanism in visual cortex. PMID:25463137

  15. Left ventricular geometry and white matter lesions in ischemic stroke patients.

    Science.gov (United States)

    Butenaerts, Demian; Chrzanowska-Wasko, Joanna; Slowik, Agnieszka; Dziedzic, Tomasz

    2016-06-01

    Abnormal left ventricular (LV) geometry is associated with extracardiac organ damage in patients with hypertension. The aim of this study was to determine the relationship between LV geometry and white matter lesions (WMLs) in ischemic stroke patients. We retrospectively analyzed data from 155 patients (median age 62; 49.8% male) with mild ischemic stroke (median National Institutes of Health Stroke Scale score 4) who underwent brain magnetic resonance imaging and echocardiography. Patients were categorized into four groups: normal LV geometry, concentric remodeling, eccentric left ventricular hypertrophy (LVH) and concentric LVH. WMLs were graded using the Fazekas scale on fluid-attenuated inversion recovery images. Extensive WMLs were defined as a Fazekas score > 2. Extensive WMLs were more prevalent in patients with concentric LVH, eccentric LVH and concentric remodeling than in those with normal LV geometry. After adjusting for hypertension, age, diabetes mellitus, hypercholesterolemia, glomerular filtration rate and ischemic heart disease, patients with concentric remodeling [odds ratio (OR) 3.94, 95% confidence interval (CI) 1.26-12.31, p = 0.02] and those with concentric LVH (OR 3.69, 95% CI 1.24-10.95, p = 0.02), but not patients with eccentric LVH (OR 2.44, 95% CI 0.72-8.29, p = 0.15), had higher risk of extensive WMLs than patients with normal LV geometry.

  16. Reduction of prohibitin expression contributes to left ventricular hypertrophy via enhancement of mitochondrial reactive oxygen species formation in spontaneous hypertensive rats.

    Science.gov (United States)

    Zheng, H; Lu, G M

    2015-02-01

    Left ventricular hypertrophy (LVH) in hypertension is characterized by thickening of myocardium and decrease in heart chamber volume in response to mechanical or pathological stress, but the underlying molecular mechanisms remain to be defined. In this work, we investigate whether mitochondrial prohibitin (PHB) was involved in the progression of LVH in spontaneous hypertensive rats (SHR). First, it was found that mitochondrial dysfunction occurred in left ventricles of SHR. Through analysis using quantitative reverse transcription polymerase chain reaction and Western blotting, it was found that PHB mRNA and mitochondrial PHB levels in left ventricles of SHR were significantly lower than that in Wistar-Kyoto rats. Furthermore, PHB mRNA levels were negatively correlated to left ventricles weight-to-body weight ratio in SHR. Knockdown of PHB led to increased formation of mitochondrial reactive oxygen species (ROS) and reduced activities of complex I, mitochondrial adenosine triphosphate generation and mitochondrial membrane potential in cultured cardiomyocytes. Knockdown of PHB contributed to the cardiomyocyte hypertrophy, which could be attenuated by treatment with the Tempol. Angiotensin II (AngII) was increased in plasma and left ventricles of SHR. Incubation with AngII reduced mitochondrial PHB expression in cardiomyocytes, which was reversed when pretreated with losartan. In conclusion, reduction of PHB expression in left ventricles in SHR contributed to LVH, at least in part, through promoting mitochondrial ROS formation.

  17. Left Hand Dominance Affects Supra-Second Time Processing

    OpenAIRE

    Carmelo Mario Vicario; Sonia eBonnì; Giacomo eKoch

    2011-01-01

    Previous studies exploring specific brain functions of left- and right-handed subjects have shown variances in spatial and motor abilities that might be explained according to consistent structural and functional differences. Given the role of both spatial and motor information in the processing of temporal intervals, we designed a study aimed at investigating timing abilities in left-handed subjects. To this purpose both left- and right-handed subjects were asked to perform a time reproducti...

  18. Pseudoaneurysm of Left Ventricle following Staphylococcal Pericarditis in a Child

    OpenAIRE

    Kamaldeep Arora; Rashmi Ranjan Das; Rohit Tandon; Kajal Goyal; Shasanka Shekhar Panda

    2015-01-01

    Formation of pseudo-aneurysm of the left ventricle is a rare entity particularly in the pediatric age group. We report a case of a pseudo-aneurysm of the left ventricle in a 6-year-old boy who initially presented to us with staphylococcus aureus septicemia. The left ventricular pseudo-aneurysm was surgically resected and the boy was discharged in a healthy condition.

  19. Left-Handedness in Professional and Amateur Tennis

    OpenAIRE

    Florian Loffing; Norbert Hagemann; Bernd Strauss

    2012-01-01

    Negative frequency-dependent effects rather than innate predispositions may provide left-handers with an advantage in one-on-one fighting situations. Support mainly comes from cross-sectional studies which found significantly enhanced left-hander frequencies among elite athletes exclusively in interactive sports such as baseball, cricket, fencing and tennis. Since professional athletes' training regimes continuously improve, however, an important unsolved question is whether the left-handers'...

  20. Echocardiographic left ventricular hypertrophy in Chinese endurance athletes.

    OpenAIRE

    Lo, Y S; Chin, M K

    1990-01-01

    Most echocardiographic data on the athletic heart syndrome originate from the United States and Western Europe. There are no published data on echocardiographically documented left ventricular hypertrophy in Asian athletes. We investigated the echocardiographic changes which take place with endurance training by studying eight Hong Kong national cyclists. This study confirms that left ventricular hypertrophy and increased left ventricular end-diastolic dimensions are common findings in Chines...

  1. Left-handed surgical instruments - a guide for cardiac surgeons.

    Science.gov (United States)

    Burdett, Clare; Theakston, Maureen; Dunning, Joel; Goodwin, Andrew; Kendall, Simon William Henry

    2016-08-19

    For ease of use and to aid precision, left-handed instruments are invaluable to the left-handed surgeon. Although they exist, they are not available in many surgical centres. As a result, most operating theatre staff (including many left-handers) have little knowledge of their value or even application. With specific reference to cardiac surgery, this article addresses the ways in which they differ, why they are needed and what is required - with tips on use.

  2. Overlay Technique for Transcatheter Left Atrial Appendage Closure.

    Science.gov (United States)

    Li, Shuang; Zhu, Mengyun; Lu, Yunlan; Tang, Kai; Zhao, Dongdong; Chen, Wei; Xu, Yawei

    2015-08-01

    The Overlay technique is popular in peripheral artery interventions, but not in coronary or cardiac structural procedures. We present an initial experience using three-episode overlays during a transcatheter left atrial appendage closure. The first overlay was applied to facilitate advancement of the delivery sheath into left atrium. The second overlay was used to navigate the advancement of prepped delivery system containing the compressed occluder into its optimal position in the left atrium. The third overlay facilitated the real-time deployment of the closure device. This case report demonstrates the effectiveness of the overlay technique in facilitating each step of the transcatheter left atrial appendage closure.

  3. Right upper lobe lung cancer: Resection through left anterior mediastinotomy.

    Science.gov (United States)

    Sirois, Marco; Abu Arab, Walid; Turcotte, Eric; Poulin, Yannick

    2016-01-01

    There is sparse information concerning approaches to metachronous lung cancer in patients who had a previous pneumonectomy for lung carcinoma. We describe the case of a 55-year-old woman who underwent a left pneumonectomy for lung carcinoma. Four years later, a radiological examination revealed a hypermetabolic nodule in the right upper lobe, which was located in the left hemithorax because of right lung hyperinflation and a mediastinal shift to the left. Wedge resection was carried out through a left anterior mediastinotomy. We believe that an anterior mediastinotomy represents a valuable option for the management of recurrent lung cancer after previous surgery. PMID:26124429

  4. Long pentraxin PTX3 exacerbates pressure overload-induced left ventricular dysfunction.

    Directory of Open Access Journals (Sweden)

    Satoshi Suzuki

    Full Text Available BACKGROUND: Left ventricular hypertrophy is enhanced by an inflammatory state and stimulation of various cytokines. Pentraxin 3 (PTX3 is rapidly produced in response to inflammatory signals, and high plasma PTX3 levels are seen in patients with heart failure. This study aimed to examine the influence of PTX3 on cardiac hypertrophy and left ventricular dysfunction with respect to pressure overload. METHODS AND RESULTS: PTX3 systemic knockout (PTX3-KO mice, transgenic mice with cardiac-specific overexpression of PTX3 (PTX3-TG, and the respective wild-type (WT littermate mice were subjected to transverse aortic constriction (TAC or a sham operation. Cardiac PTX3 expression increased after TAC in WT mice. In vitro, hydrogen peroxide induced the expression of PTX3 in both cardiac myocytes and cardiac fibroblasts. Recombinant PTX3 phosphorylated extracellular signal-regulated kinase 1/2 (ERK1/2 in cardiac fibroblasts. Phosphorylation of cardiac ERK1/2 and nuclear factor kappa-B after TAC was attenuated in the PTX3-KO mice but was enhanced in the PTX3-TG mice compared with WT mice. Interleukin-6 and connective tissue growth factor production was lower in the PTX3-KO mice than in the WT mice, but this was augmented in the PTX3-TG mice than in the WT mice. Echocardiography revealed that adverse remodeling with left ventricular dysfunction, as well as with increased interstitial fibrosis, was enhanced in PTX3-TG mice, while these responses were suppressed in PTX3-KO mice. CONCLUSION: The local inflammatory mediator PTX3 directly modulates the hypertrophic response and ventricular dysfunction following an increased afterload.

  5. What’s on the left?

    Directory of Open Access Journals (Sweden)

    Paul Isambert

    2011-07-01

    Full Text Available Discourse structure is investigated from the point of view of topic shifts. The paper focuses on the French adverb autrement, an important tool in such operations. It requires an antecedent, the topic to be shifted, which it generally finds among salient elements such as topicalized noun phrases or frames. However, since there might be several such elements in the left context, other devices are used to ensure that interlocutors clearly understand which topic is being shifted, i.e. what the antecedent of autrement is. These devices are mostly: stating the new topic, which is similar in many respects (syntax, semantics to the previous one; the repetition of an overarching topic is also an important way to clarify discourse structure. In cases where such markers are absent, it is hypothesized that topics exist at least covertly. On the whole, discourse structure, and especially the left context, must be highly organized if autrement is to work properly. Thus, the study of autrement offers an interesting perspective on discourse structure as a whole, including the Right Frontier constraint: not only does autrement find its antecedent on the Right Frontier, it also shapes it by closing topics and modifying the availability of discourse referents.Cet article étudie la structure du discours du point de vue des changements de topiques, et plus précisément en se concentrant sur l’adverbe autrement et son rôle central dans une telle opération. Ce marqueur nécessite un antécédent, le topique qu’il ferme, qu’il trouve généralement parmi les éléments saillants du discours tels que les groupes nominaux topicalisés et les cadratifs. Cependant, comme il peut y avoir plusieurs éléments de cette sorte dans le contexte gauche, d’autres procédés sont aussi employés pour s’assurer que les interlocuteurs comprennent clairement quel topique est fermé, c’est-à-dire quel élément est l’antécédent d’autrement. Ces procédés sont

  6. Comparison of Left Ventricular Electromechanical Mapping and Left Ventricular Angiography: Defining Practical Standards for Analysis of NOGA™ Maps

    OpenAIRE

    Sarmento-Leite, Rogerio; Silva, Guilherme V.; Dohman, Hans F.R.; Rocha, Ricardo Mourilhe; Dohman, Hans J.F.; de Mattos, Nelson Durval S.G.; Carvalho, Luis Antonio; Gottschall, Carlos A.M.; Perin, Emerson C.

    2003-01-01

    We performed this prospective cohort study to correlate the findings of left ventricular angiography (LVA) and NOGA™ left ventricular electromechanical mapping (LVEM) in the evaluation of cardiac wall motion and also to establish standards for wall motion assessment by LVEM. Fifty-five patients (35 men; mean age, 60.4 ± 11.8 years) eligible for elective left cardiac catheterization underwent LVA and LVEM. Wall motion scores, LV ejection fractions (LVEF), and LV volumes derived from LVA versus...

  7. Stenting for left main stenosis in a child with anomalous origin of left coronary artery: case report

    Institute of Scientific and Technical Information of China (English)

    CHEN Ming; HONG Tao; HUO Yong

    2005-01-01

    @@ Anomalous left coronary artery (LCA) arising from right cusp is an uncommon condition. Clinical evidence has shown that this coronary anomaly is consistently related to sudden death. Current treatment options include modification of behaviour, medicine or surgery. Stents have been successfully applied for left main stenosis for a decade. We report a case of LCA arising from right cusp with left main stenosis treated with coronary stent in a child patient.

  8. Bronchial compression by an enlarged left atrium in infants; a cause of hypovascularity of the left lung

    Energy Technology Data Exchange (ETDEWEB)

    Corr, L.; Hallidie-Smith, K.A.; McCarthy, P.A.; Lavender, J.P.

    1988-09-01

    In three infants seen recently at our institution we noted signs of compression of the left main bronchus associated with enlarged left atria. None of our cases demonstrated the more usual signs of hyperinflation which are a hyperlucent lung field, depressed hemidiaphragm and mediastinal shift away from the affected side. In addition, hypoperfusion of the left lung was noted in each case. We believe that bronchial compression due to an enlarged left atrium, with consequent hypoxic vasoconstriction is a clinically significant entity, which is not well described and may be unappreciated in infants in whom the typical signs of hyperinflation are absent.

  9. Nipro extra-corporeal left ventricular assist device fitting after left ventricular reconstruction with mitral valve plasty.

    Science.gov (United States)

    Arakawa, Mamoru; Yamaguchi, Atsushi; Nishimura, Takashi; Itoh, Satoshi; Yuri, Koichi; Kyo, Shunei; Adachi, Hideo

    2015-12-01

    Both left ventricular assist device and left ventricular reconstruction are treatment choices for severe heart failure conditions. Our institution performed a left ventricular assist device installation following a left ventricular reconstruction procedure on a 42-year-old male patient who presented with dilated cardiomyopathy and low cardiac output syndrome. A mitral valve plasty was used to correct the acute mitral valve regurgitation and we performed a Nipro extra-corporeal left ventricular assist device installation on post-operative day 14. Due to the left ventricular reconstruction that the patient had in a previous operation, we needed to attach an apical cuff on posterior apex, insert the inflow cannula with a large curve, and shift the skin insertion site laterally to the left. We assessed the angle between the cardiac longitudinal axis and the inflow cannula using computed tomography. The patient did not complain of any subjective symptoms of heart failure. Although Nipro extra-corporeal left ventricular assist device installation after left ventricular reconstruction has several difficulties historically, we have experienced a successful case.

  10. Left atrial strain: a new parameter for assessment of left ventricular filling pressure.

    Science.gov (United States)

    Cameli, Matteo; Mandoli, Giulia Elena; Loiacono, Ferdinando; Dini, Frank Lloyd; Henein, Michael; Mondillo, Sergio

    2016-01-01

    In order to obtain accurate diagnosis, treatment and prognostication in many cardiac conditions, there is a need for assessment of left ventricular (LV) filling pressure. While systole depends on ejection function of LV, diastole and its disturbances influence filling function and pressures. The commonest condition that represents the latter is heart failure with preserved ejection fraction in which LV ejection is maintained, but diastole is disturbed and hence filling pressures are raised. Significant diastolic dysfunction results in raised LV end-diastolic pressure, mean left atrial (LA) pressure and pulmonary capillary wedge pressure, all referred to as LV filling pressures. Left and right heart catheterization has traditionally been used as the gold standard investigation for assessing these pressures. More recently, Doppler echocardiography has taken over such application because of its noninvasive nature and for being patient friendly. A number of indices are used to achieve accurate assessment of filling pressures including: LV pulsed-wave filling velocities (E/A ratio, E wave deceleration time), pulmonary venous flow (S wave and D wave), tissue Doppler imaging (E' wave and E/E' ratio) and LA volume index. LA longitudinal strain derived from speckle tracking echocardiography (STE) is also sensitive in estimating intracavitary pressures. It is angle-independent, thus overcomes Doppler limitations and provides highly reproducible measures of LA deformation. This review examines the application of various Doppler echocardiographic techniques in assessing LV filling pressures, in particular the emerging role of STE in assessing LA pressures in various conditions, e.g., HF, arterial hypertension and atrial fibrillation.

  11. Diagnosis of mediastinal and left adrenal abnormalities with endoscopic ultrasonography

    NARCIS (Netherlands)

    Kramer, H; Groen, HJM

    2005-01-01

    Endoscopic ultrasound with fine-needle aspiration (EUS-FNA) is increasingly used for sampling of mediastinal or left adrenal abnormalities. We report two patients in whom EUS-FNA led to the diagnosis of malignancy. In one patient, left adrenal metastasis of a rectal. adenocarcinoma was diagnosed, wh

  12. Benign Multicystic Mesothelioma in the Left Round Ligament: Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Bae, So Young; Yi, Boem Ha; Lee, Hae Kyung; Park, Seong Jin; Cho, Gyu Seok; Kwak, Jeong Ja [Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of)

    2010-02-15

    Benign multicystic mesothelioma is a rare mesothelial lesion that forms multicystic masses in the upper abdomen, pelvis, and retroperitoneum. Most cases have a benign course. We present the ultrasound and MR findings of benign multicystic mesothelioma in the left round ligament, which caused a left inguinal hernia in a 46-year-old woman.

  13. Fountain-Gould Left Orders for Associative Pairs

    Institute of Scientific and Technical Information of China (English)

    José A. ANQUELA; Teresa CORT(E)S; Miguel G(O)MEZ LOZANO; Mercedes SILES MOLINA

    2006-01-01

    In this paper, we introduce a notion of weak Fountain-Gould left order for associative pairs and give a Goldie-like theory of associative pairs which are weak Fountain-Gould left orders in semiprime pairs coinciding with their socles.

  14. On Functional Inequalities Originating from Module Jordan Left Derivations

    Directory of Open Access Journals (Sweden)

    Ick-Soon Chang

    2008-06-01

    Full Text Available We first examine the generalized Hyers-Ulam stability of functional inequality associated with module Jordan left derivation (resp., module Jordan derivation. Secondly, we study the functional inequality with linear Jordan left derivation (resp., linear Jordan derivation mapping into the Jacobson radical.

  15. On Functional Inequalities Originating from Module Jordan Left Derivations

    Directory of Open Access Journals (Sweden)

    Kang Sheon-Young

    2008-01-01

    Full Text Available Abstract We first examine the generalized Hyers-Ulam stability of functional inequality associated with module Jordan left derivation (resp., module Jordan derivation. Secondly, we study the functional inequality with linear Jordan left derivation (resp., linear Jordan derivation mapping into the Jacobson radical.

  16. Imagining No Child Left Behind Freed from Neoliberal Hijackers

    Science.gov (United States)

    Matusov, Eugene

    2011-01-01

    As a sociocultural educator and scholar, I have always been ambivalent about No Child Left Behind's slogan. I like its democratic ideal of "education without failure," but I do not like the current educational policies guided by a neoliberal ideology. This article begins a discussion about what a No Student Left Behind educational practice might…

  17. Cortical Reorganization of Language Functioning Following Perinatal Left MCA Stroke

    Science.gov (United States)

    Tillema, Jan-Mendelt; Byars, Anna W.; Jacola, Lisa M.; Schapiro, Mark B.; Schmithorst, Vince J.; Szaflarski, Jerzy P.; Holland, Scott K.

    2008-01-01

    Objective: Functional MRI was used to determine differences in patterns of cortical activation between children who suffered perinatal left middle cerebral artery (MCA) stroke and healthy children performing a silent verb generation task. Methods: Ten children with prior perinatal left MCA stroke (age 6-16 years) and ten healthy age matched…

  18. Left ventricular metastasis from a primary lung carcinoma

    Institute of Scientific and Technical Information of China (English)

    CHE Guo-wei; LIU Lun-xu; ZHANG Er-yong; ZHOU Qing-hua

    2007-01-01

    @@ The most common tumors associated with cardiac metastases are lung carcinoma and melanoma.1 Although the cardiac involvement of lung cancer is common(lung cancer usually directly invades into the pericardium and/or left/right atrium),the primary lung cancer accompanied with metastasis to the left ventricle is extremely rare.

  19. An exceptional cause of left lower quadrant abdominal pain

    Institute of Scientific and Technical Information of China (English)

    Bassam Abboud; Ronald Daher

    2009-01-01

    Acute appendicitis is an exceptional cause of left lower quadrant abdominal pain. Computed tomography scan is the key to its diagnosis and helps to establish its early treatment. We present a case of a 35-year-old male patient who presented acute appendicitis with redundant and loosely attached cecum which was diagnosed based on his left lower quadrant abdominal pain.

  20. On Functional Inequalities Originating from Module Jordan Left Derivations

    OpenAIRE

    Kang Sheon-Young; Chang Ick-Soon; Kim Hark-Mahn

    2008-01-01

    Abstract We first examine the generalized Hyers-Ulam stability of functional inequality associated with module Jordan left derivation (resp., module Jordan derivation). Secondly, we study the functional inequality with linear Jordan left derivation (resp., linear Jordan derivation) mapping into the Jacobson radical.

  1. Left paramesocolic hernia presenting as post appendicectomy abdominal cocoon.

    Science.gov (United States)

    Patel, Ramnik; Gabra, H Os; Nour, Shawqui

    2010-11-01

    We describe a rare case of left mesocolic hernia presenting as post appendicectomy intestinal obstruction in a girl. Laparotomy confirmed partial peritoneal encapsulation of upper small bowel due to herniation of jejunal loops into the left mesocolic hernia sac. Reduction of contents, resection of the sac and repair of the defect concluded the procedure uneventfully. PMID:21149902

  2. Urban School Principals and the "No Child Left Behind" Act

    Science.gov (United States)

    Gardiner, Mary E.; Canfield-Davis, Kathy; Anderson, Keith LeMar

    2009-01-01

    This exploratory study investigated how six practicing school principals responded to the requirements of the No Child Left Behind law (United States Congress Public Law 107-110, 2002, January, No Child Left Behind Act, http://www.ed.gov/policy/elsec/leg/esea02/107-110.pdf ) in light of the multicultural leadership demands presented by an urban…

  3. Foucault's Flirt? Neoliberalism, the Left and the Welfare State

    DEFF Research Database (Denmark)

    Hansen, Magnus Paulsen

    2015-01-01

    An essay on the review of works interpreting the lectures of Michel Foucault on neoliberalism is presented. It offers a history of neoliberalism as a way to reinvent the left and examines the way Foucault betrayed the left while resisting to be connected with a normative political programme...

  4. Persistent Left Unilateral Mirror Writing: A Neuropsychological Case Study

    Science.gov (United States)

    Angelillo, Valentina G.; De Lucia, Natascia; Trojano, Luigi; Grossi, Dario

    2010-01-01

    Mirror writing (MW) is a rare disorder in which a script runs in direction opposite to normal and individual letters are reversed. The disorder generally occurs after left-hemisphere lesions, is transient and is observed on the left hand, whereas usually motor impairments prevent assessment of direction of right handwriting. We describe a…

  5. Left-Handed Preschool Children with Orthopedic Disabilities.

    Science.gov (United States)

    Banham, Katharine M.

    1983-01-01

    The mental development of 332 preschool-age children with orthopedic disabilities was assessed at a children's hospital over a 10-year period, and comparisons were made for right-handed and left-handed. The left-handed children were slower than right-handed children in learning speech and language skills (Author/SEW)

  6. Enantioselective targeting left-handed Z-G-quadruplex.

    Science.gov (United States)

    Zhao, Andong; Zhao, Chuanqi; Ren, Jinsong; Qu, Xiaogang

    2016-01-25

    Herein, we report the first example where an M-enantiomer of a chiral metal complex can selectively stabilize a left-handed G-quadruplex, but its P-enantiomer cannot. The interactions between the chiral metal complexes and the left-handed G-quadruplex were evaluated by UV melting, circular dichroism, isothermal titration calorimetry, gel electrophoresis and NMR titrations.

  7. Interleukin-2/Anti-Interleukin-2 Immune Complex Attenuates Cardiac Remodeling after Myocardial Infarction through Expansion of Regulatory T Cells

    OpenAIRE

    Zhipeng Zeng; Kunwu Yu; Long Chen; Weihua Li; Hong Xiao; Zhengrong Huang

    2016-01-01

    CD4+CD25+Foxp3+ regulatory T cells (Treg cells) have protective effects in wound healing and adverse ventricular remodeling after myocardial infarction (MI). We hypothesize that the interleukin- (IL-) 2 complex comprising the recombinant mouse IL-2/anti-IL-2 mAb (JES6-1) attenuates cardiac remodeling after MI through the expansion of Treg. Mice were subjected to surgical left anterior descending coronary artery ligation and treated with either PBS or IL-2 complex. The IL-2 complex significant...

  8. Vinpocetine attenuates lipid accumulation and atherosclerosis formation

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Yujun [Aab Cardiovascular Research Institute, Department of Medicine, University of Rochester, 601 Elmwood Ave, Rochester, NY 14642 (United States); Li, Jian-Dong [Center for Inflammation, Immunity and Infection, and Department of Biology, Georgia State University, Atlanta, GA 30303 (United States); Yan, Chen, E-mail: Chen_Yan@urmc.rochester.edu [Aab Cardiovascular Research Institute, Department of Medicine, University of Rochester, 601 Elmwood Ave, Rochester, NY 14642 (United States)

    2013-05-10

    Highlights: •Vinpocetine attenuates hyperlipidemia-induced atherosclerosis in a mouse model. •Vinpocetine antagonizes ox-LDL uptake and accumulation in macrophages. •Vinpocetine blocks the induction of ox-LDL receptor LOX-1 in vitro and in vivo. -- Abstract: Atherosclerosis, the major cause of myocardial infarction and stroke, is a chronic arterial disease characterized by lipid deposition and inflammation in the vessel wall. Cholesterol, in low-density lipoprotein (LDL), plays a critical role in the pathogenesis of atherosclerosis. Vinpocetine, a derivative of the alkaloid vincamine, has long been used as a cerebral blood flow enhancer for treating cognitive impairment. Recent study indicated that vinpocetine is a potent anti-inflammatory agent. However, its role in the pathogenesis of atherosclerosis remains unexplored. In the present study, we show that vinpocetine significantly reduced atherosclerotic lesion formation in ApoE knockout mice fed with a high-fat diet. In cultured murine macrophage RAW264.7 cells, vinpocetine markedly attenuated oxidized LDL (ox-LDL) uptake and foam cell formation. Moreover, vinpocetine greatly blocked the induction of ox-LDL receptor 1 (LOX-1) in cultured macrophages as well as in the LOX-1 level in atherosclerotic lesions. Taken together, our data reveal a novel role of vinpocetine in reduction of pathogenesis of atherosclerosis, at least partially through suppressing LOX-1 signaling pathway. Given the excellent safety profile of vinpocetine, this study suggests vinpocetine may be a therapeutic candidate for treating atherosclerosis.

  9. Exercise Training During Bed Rest Attenuates Deconditioning

    Science.gov (United States)

    Greenleaf, J. E.; Hargens, Alan R. (Technical Monitor)

    1995-01-01

    A 30-day 6 deg. head-down bed rest study was conducted to evaluate high-intensity, short-duration, alternating isotonic cycle ergometer exercise (ITE) training and high-intensity intermittent isokinetic exercise (IKE) training regiments designed to maintain peak VO2 and muscle mass, strength, and endurance at ambulatory control levels throughout prolonged bed rest. Other elements of the deconditioning (acclimation) syndrome, such as proprioception, psychological performance, hypovolemia, water balance, body composition, and orthostatic tolerance, were also measured. Compared with response during bed rest of the no exercise (NOE) control group: the ITE training regimen (a) maintained work capacity (peak VO2), (b) maintained plasma and red cell volume, (c) induced positive body water balance, (d) decreased quality of sleep and mental concentration, and (e) had no effect on the decrease in orthostatic tolerance; the IKE training regimen (a) attenuated the decrease in peak VO2 by 50%, (b) attenuated loss of red cell volume by 40%, but had no effect on loss of plasma volume, (c) induced positive body water balance, (d) had no adverse effect on quality of sleep or concentration, and (e) had no effect on the decrease in orthostatic tolerance. These findings suggest that various elements of the deconditioning syndrome can be manipulated by duration and intensity of ITE or IKE training regiments, and that several different training protocols will be required to maintain or restore physiological and psychological performance of individuals confined to prolonged bed rest.

  10. Vinpocetine attenuates lipid accumulation and atherosclerosis formation

    International Nuclear Information System (INIS)

    Highlights: •Vinpocetine attenuates hyperlipidemia-induced atherosclerosis in a mouse model. •Vinpocetine antagonizes ox-LDL uptake and accumulation in macrophages. •Vinpocetine blocks the induction of ox-LDL receptor LOX-1 in vitro and in vivo. -- Abstract: Atherosclerosis, the major cause of myocardial infarction and stroke, is a chronic arterial disease characterized by lipid deposition and inflammation in the vessel wall. Cholesterol, in low-density lipoprotein (LDL), plays a critical role in the pathogenesis of atherosclerosis. Vinpocetine, a derivative of the alkaloid vincamine, has long been used as a cerebral blood flow enhancer for treating cognitive impairment. Recent study indicated that vinpocetine is a potent anti-inflammatory agent. However, its role in the pathogenesis of atherosclerosis remains unexplored. In the present study, we show that vinpocetine significantly reduced atherosclerotic lesion formation in ApoE knockout mice fed with a high-fat diet. In cultured murine macrophage RAW264.7 cells, vinpocetine markedly attenuated oxidized LDL (ox-LDL) uptake and foam cell formation. Moreover, vinpocetine greatly blocked the induction of ox-LDL receptor 1 (LOX-1) in cultured macrophages as well as in the LOX-1 level in atherosclerotic lesions. Taken together, our data reveal a novel role of vinpocetine in reduction of pathogenesis of atherosclerosis, at least partially through suppressing LOX-1 signaling pathway. Given the excellent safety profile of vinpocetine, this study suggests vinpocetine may be a therapeutic candidate for treating atherosclerosis

  11. Towards a Global Upper Mantle Attenuation Model

    Science.gov (United States)

    Karaoglu, Haydar; Romanowicz, Barbara

    2015-04-01

    Global anelastic tomography is crucial for addressing the nature of heterogeneity in the Earth's interior. The intrinsic attenuation manifests itself through dispersion and amplitude decay. These are contaminated by elastic effects such as (de)focusing and scattering. Therefore, mapping anelasticity accurately requires separation of elastic effects from the anelastic ones. To achieve this, a possible approach is to try and first predict elastic effects through the computation of seismic waveforms in a high resolution 3D elastic model, which can now be achieved accurately using numerical wavefield computations. Building upon the recent construction of such a whole mantle elastic and radially anisotropic shear velocity model (SEMUCB_WM1, French and Romanowicz, 2014), which will be used as starting model, our goal is to develop a higher resolution 3D attenuation model of the upper mantle based on full waveform inversion. As in the development of SEMUCB_WM1, forward modeling will be performed using the spectral element method, while the inverse problem will be treated approximately, using normal mode asymptotics. Both fundamental and overtone time domain long period waveforms (T>60s) will be used from a dataset of over 200 events observed at several hundred stations globally. Here we present preliminary results of synthetic tests, exploring different iterative inversion strategies.

  12. Live attenuated influenza vaccine--a review.

    Science.gov (United States)

    Gasparini, R; Amicizia, D; Lai, P L; Panatto, D

    2011-09-01

    Owing to the variability of influenza viruses, vaccine composition needs to be up-dated annually. As many variables can influence their efficacy, vaccines are still considered "sub-optimal". Many studies have been carried out in recent years to improve vaccines. In particular, researchers and vaccine-producing corporations have focused on developing a live vaccine. Among the candidate vaccines, the strain developed by Maassab has recently been licensed in the USA and Europe, after extensive investigation. This vaccine is safe and well tolerated, and has shown very good genetic stability. Although vaccine recipients are able to spread the virus, transmission to close contacts is practically non-existent. Studies on cold-adapted attenuated influenza vaccines have demonstrated that such vaccines are effective, and sometimes more effective than inactivated influenza vaccines. Cold-adapted attenuated influenza vaccines therefore appear to be an important weapon against influenza. However, a more widespread use of these vaccines is to be recommended, especially in children, as the more acceptable way of administration can favour parental compliance.

  13. CABG surgery in a patient with left iliac artery occlusion

    Directory of Open Access Journals (Sweden)

    Oscar F. De La Peña Brush

    2015-09-01

    Full Text Available We present the case of an 82 years old male with Congestive Heart Failure (Left Ventricle Ejection Fraction: 20% and Acute Pulmonary Edema secondary to Acute Myocardial Infarction that required Coronary Artery Bypass Graft (CABG surgery. Past Medical History included Aortoiliac Occlusive Ddisease with total occlusion of the Left Iliac Artery and collateral circulation to the left inferior limb through the Left Internal Mammary Artery (LIMA. CABG was perfomed without harvesting the LIMA due to high risk of leg ischemia. An attempt to revascularize the left limb previous to the cardiac surgery in other to do so. Would have been too risky in this case. After 2 months follow up, patient showed good clinical outcomes.

  14. Left testicular artery arching over the ipsilateral renal vein

    Institute of Scientific and Technical Information of China (English)

    Munekazu Naito; Hayato Terayama; Yoichi Nakamura; Shogo Hayashi; Takayoshi Miyaki; Masahiro Itoh

    2006-01-01

    Aim: To report two cases of the left testicular artery arching over the left renal vein (LRV) before running downward to the testis. Methods: The subjects were obtained from two Japanese cadavers. During the student course of gross-anatomical dissection, the anatomical relationship between the testicular vessels and the renal vein was specifically observed. Results: The arching left testicular artery arose from the aorta below the LRV and made a loop around the LRV, which appeared to be mildly compressed between the arching artery and the psoas major muscle.Conclusion: Clinically, compression of the LRV between the abdominal aorta and the superior mesenteric artery occasionally induces LRV hypertension, resulting in varicocele, orthostatic protenuria and hematuria. Considering that the incidence of a left arching testicular artery is higher than that of a right one, an arching left artery could be an additional cause of LRV hypertension.

  15. Intra-coronary administration of tacrolimus markedly attenuates infarct size and preserves heart function in porcine myocardial infarction

    Directory of Open Access Journals (Sweden)

    Chua Sarah

    2012-06-01

    Full Text Available Abstract Background We test the hypothesis that intra-coronary tacrolimus administration can limit infarct size and preserve left ventricular ejection fraction (LVEF after acute myocardial infarction (AMI through ligating left anterior descending coronary artery (LAD in mini-pigs. Methods Twelve male mini-pigs were randomized into AMI-saline (MI-only group and AMI-tacrolimus (MI-Tac group that received intra-coronary saline (3.0 mL and tacrolimus (0.5 mg in 2.5 mL saline injection, respectively, beyond site of ligation 30 minutes after LAD occlusion. Results Larger infarct area was noted in MI-only group (p  Conclusion Intra-coronary administration of tacrolimus significantly attenuated infarct size and preserved LV function.

  16. Applying Echoes Mean Frequency Shift for Attenuation Imaging in Tissue

    Science.gov (United States)

    Litniewski, J.; Klimonda, Z.; Nowicki, A.

    The purpose of this study was to develop the attenuation parametric imaging technique and to apply it for in vivo characterization of tissue. Local attenuation coefficient was determined by evaluating the frequency downshift that encounters the amplitude spectrum of the interrogating ultrasonic pulse during propagation in the absorbing tissue. Operation and accuracy of the processing methods were verified by assessing the size-independent region of interest (ROI) for attenuation determination and calculating the attenuation coefficient distribution for experimentally recorded tissue-phantom scattered waveforms. The Siemens Antares scanner equipped with Ultrasound Research Interface unit allowing for direct radiofrequency (RF) signals recording was used for B-scan imaging of the tissue- mimicking phantom in vitro and liver in vivo. RF data were processed to determine attenuation coefficient along the B-scan lines. Also, the preliminary studies of backscattered signals from skin recorded using a skin scanner were performed to calculate parametric-attenuation images.

  17. Effect of Left Ventricular Outflow Tract Obstruction on Left Atrial Mechanics in Hypertrophic Cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Lynne K. Williams

    2015-01-01

    Full Text Available Left atrial (LA volumes are known to be increased in hypertrophic cardiomyopathy (HCM and are a predictor of adverse outcome. In addition, LA function is impaired and is presumed to be due to left ventricular (LV diastolic dysfunction as a result of hypertrophy and myocardial fibrosis. In the current study, we assess the incremental effect of outflow tract obstruction (and concomitant mitral regurgitation on LA function as assessed by LA strain. Patients with HCM (50 obstructive, 50 nonobstructive were compared to 50 normal controls. A subset of obstructive patients who had undergone septal myectomy was also studied. Utilising feature-tracking software applied to cardiovascular magnetic resonance images, LA volumes and functional parameters were calculated. LA volumes were significantly elevated and LA ejection fraction and strain were significantly reduced in patients with HCM compared with controls and were significantly more affected in patients with obstruction. LA volumes and function were significantly improved after septal myectomy. LVOT obstruction and mitral regurgitation appear to further impair LA mechanics. Septal myectomy results in a significant reduction in LA volumes, paralleled by an improvement in function.

  18. Left neglect dyslexia: Perseveration and reading error types.

    Science.gov (United States)

    Ronchi, Roberta; Algeri, Lorella; Chiapella, Laura; Gallucci, Marcello; Spada, Maria Simonetta; Vallar, Giuseppe

    2016-08-01

    Right-brain-damaged patients may show a reading disorder termed neglect dyslexia. Patients with left neglect dyslexia omit letters on the left-hand-side (the beginning, when reading left-to-right) part of the letter string, substitute them with other letters, and add letters to the left of the string. The aim of this study was to investigate the pattern of association, if any, between error types in patients with left neglect dyslexia and recurrent perseveration (a productive visuo-motor deficit characterized by addition of marks) in target cancellation. Specifically, we aimed at assessing whether different productive symptoms (relative to the reading and the visuo-motor domains) could be associated in patients with left spatial neglect. Fifty-four right-brain-damaged patients took part in the study: 50 out of the 54 patients showed left spatial neglect, with 27 of them also exhibiting left neglect dyslexia. Neglect dyslexic patients who showed perseveration produced mainly substitution neglect errors in reading. Conversely, omissions were the prevailing reading error pattern in neglect dyslexic patients without perseveration. Addition reading errors were much infrequent. Different functional pathological mechanisms may underlie omission and substitution reading errors committed by right-brain-damaged patients with left neglect dyslexia. One such mechanism, involving the defective stopping of inappropriate responses, may contribute to both recurrent perseveration in target cancellation, and substitution errors in reading. Productive pathological phenomena, together with deficits of spatial attention to events taking place on the left-hand-side of space, shape the manifestations of neglect dyslexia, and, more generally, of spatial neglect. PMID:27450268

  19. Left-handedness in professional and amateur tennis.

    Directory of Open Access Journals (Sweden)

    Florian Loffing

    Full Text Available Negative frequency-dependent effects rather than innate predispositions may provide left-handers with an advantage in one-on-one fighting situations. Support mainly comes from cross-sectional studies which found significantly enhanced left-hander frequencies among elite athletes exclusively in interactive sports such as baseball, cricket, fencing and tennis. Since professional athletes' training regimes continuously improve, however, an important unsolved question is whether the left-handers' advantage in individual sports like tennis persists over time. To this end, we longitudinally tracked left-hander frequencies in year-end world rankings (men: 1973-2011, ladies: 1975-2011 and at Grand Slam tournaments (1968-2011 in male and female tennis professionals. Here we show that the positive impact of left-handed performance on high achievement in elite tennis was moderate and decreased in male professionals over time and was almost absent in female professionals. For both sexes, left-hander frequencies among year-end top 10 players linearly decreased over the period considered. Moreover, left-handedness was, however, no longer seems associated with higher probability of attaining high year-end world ranking position in male professionals. In contrast, cross-sectional data on left-hander frequencies in male and female amateur players suggest that a left-handers' advantage may still occur on lower performance levels. Collectively, our data is in accordance with the frequency-dependent hypothesis since reduced experience with left-handers in tennis is likely to be compensated by players' professionalism.

  20. Left and right ventricular diastolic function in hemodialysis patients

    Directory of Open Access Journals (Sweden)

    Rudhani Ibrahim

    2010-01-01

    Full Text Available The aim of this prospective study was the assessment of left ventricular and right ventricular diastolic function in patients on hemodialysis (HD and the correlation of this func-tion with the duration of HD. The study included 42 patients (22 females and 20 males with chro-nic renal failure (CRF, treated with HD, and 40 healthy subjects (24 females and 16 males with no history of cardiovascular disease and with normal renal function, who constituted the control group. The groups were matched for age and sex. All study patients and control subjects under-went detailed history taking and physical examination. They also underwent electrocardiogram, echocardiography and biochemical and hematological blood analyses. Significant differences were noted between the two groups in the two-dimensional and M-mode echocardiography findings concerning aortic root dimension, transverse diameter of the left atrium, thickness of the inter-ventricular septum, thickness of the left ventricular posterior wall, left ventricular diastolic diameter, left ventricular systolic diameter, shortening fraction, ejection fraction as well as findings from the pulse Doppler study, including E wave, A wave, E/A ratio, deceleration time of E wave (DT-E, acceleration time of E wave (AT-E, tricuspid E and A waves (E tr and A tr and E tr /A tr , ratio. There were significant changes in HD patients without arterial hypertension as well in the control group subjects. Our study suggests that the left ventricular and left atrial dimensions as well as the left ventricular wall thickness are augmented in patients with CRF treated with HD compared with the control group. Additionally, the left and right ventricular diastolic function is also reduced in these patients. These differences were also noted in patients with CRF without arterial hypertension. Left ventricular diastolic dysfunction had no correlation with the duration of HD.

  1. Left and right ventricular diastolic function in hemodialysis patients.

    Science.gov (United States)

    Rudhani, Ibrahim Destan; Bajraktari, Gani; Kryziu, Emrush; Zylfiu, Bejtush; Sadiku, Shemsedin; Elezi, Ymer; Rexhepaj, Nehat; Vitia, Arber; Emini, Merita; Abazi, Murat; Berbatovci-Ukimeraj, M; Kryeziu, Kaltrina; Hsanagjekaj, Venera; Korca, Hajrije; Ukimeri, Aferdita

    2010-11-01

    The aim of this prospective study was the assessment of left ventricular and right ventricular diastolic function in patients on hemodialysis (HD) and the correlation of this function with the duration of HD. The study included 42 patients (22 females and 20 males) with chronic renal failure (CRF), treated with HD, and 40 healthy subjects (24 females and 16 males) with no history of cardiovascular disease and with normal renal function, who constituted the control group. The groups were matched for age and sex. All study patients and control subjects underwent detailed history taking and physical examination. They also underwent electrocardiogram, echocardiography and biochemical and hematological blood analyses. Significant differences were noted between the two groups in the two-dimensional and M-mode echocardiography findings concerning aortic root dimension, transverse diameter of the left atrium, thickness of the interventricular septum, thickness of the left ventricular posterior wall, left ventricular diastolic diameter, left ventricular systolic diameter, shortening fraction, ejection fraction as well as findings from the pulse Doppler study, including E wave, A wave, E/A ratio, deceleration time of E wave (DT-E), acceleration time of E wave (AT-E), tricuspid E and A waves (E tr and A tr ) and E tr /A tr , ratio. There were significant changes in HD patients without arterial hypertension as well in the control group subjects. Our study suggests that the left ventricular and left atrial dimensions as well as the left ventricular wall thickness are augmented in patients with CRF treated with HD compared with the control group. Additionally, the left and right ventricular diastolic function is also reduced in these patients. These differences were also noted in patients with CRF without arterial hypertension. Left ventricular diastolic dysfunction had no correlation with the duration of HD.

  2. Left neglect dyslexia: Perseveration and reading error types.

    Science.gov (United States)

    Ronchi, Roberta; Algeri, Lorella; Chiapella, Laura; Gallucci, Marcello; Spada, Maria Simonetta; Vallar, Giuseppe

    2016-08-01

    Right-brain-damaged patients may show a reading disorder termed neglect dyslexia. Patients with left neglect dyslexia omit letters on the left-hand-side (the beginning, when reading left-to-right) part of the letter string, substitute them with other letters, and add letters to the left of the string. The aim of this study was to investigate the pattern of association, if any, between error types in patients with left neglect dyslexia and recurrent perseveration (a productive visuo-motor deficit characterized by addition of marks) in target cancellation. Specifically, we aimed at assessing whether different productive symptoms (relative to the reading and the visuo-motor domains) could be associated in patients with left spatial neglect. Fifty-four right-brain-damaged patients took part in the study: 50 out of the 54 patients showed left spatial neglect, with 27 of them also exhibiting left neglect dyslexia. Neglect dyslexic patients who showed perseveration produced mainly substitution neglect errors in reading. Conversely, omissions were the prevailing reading error pattern in neglect dyslexic patients without perseveration. Addition reading errors were much infrequent. Different functional pathological mechanisms may underlie omission and substitution reading errors committed by right-brain-damaged patients with left neglect dyslexia. One such mechanism, involving the defective stopping of inappropriate responses, may contribute to both recurrent perseveration in target cancellation, and substitution errors in reading. Productive pathological phenomena, together with deficits of spatial attention to events taking place on the left-hand-side of space, shape the manifestations of neglect dyslexia, and, more generally, of spatial neglect.

  3. A wideband IM3 cancellation technique for CMOS attenuators

    NARCIS (Netherlands)

    Cheng, W.; Oude Alink, M.S.; Annema, A.J.; Wienk, G.J.M.; Nauta, B.

    2012-01-01

    A highly linear P attenuator system using a wideband IM3 cancellation technique is presented that provides 4 discrete attenuation levels with 6dB spacing for DC-5GHz. For the whole band, S11<-14dB, attenuation flatness<1.6dB, +10dBm input P1dB and +26dBm IIP3 are achieved. For the TV band (0.1Gz-1.2

  4. Compression of left main bronchus with collapse of left lung by a large descending thoracic aortic aneurysm: A case report

    Directory of Open Access Journals (Sweden)

    Khushal N. Pawar, Dilip L. Lakhkar, Sushil Nemane, Sandeep Shinde

    2013-07-01

    Full Text Available We report a case of 60 years old female who presented with a history of progressive breathlessness over a period of one year. CECT thorax revealed a large aneurysm of descending thoracic aorta which was causing compression of left main bronchus with resultant complete collapse of left lung. There was a contralateral shift of the trachea and mediastinum.

  5. An intramural left main coronary artery with a left sinus of valsalva aneurysm: a unique combination of congenital anomalies.

    Science.gov (United States)

    Altarabsheh, Salah Eldien; Deo, Salil V; Spitell, Peter; Araoz, Philip; Park, Soon J

    2013-02-01

    The congenital anomaly of an intramural left main coronary artery arising in the anatomically correct aortic sinus is very infrequent. Aneurysms involving the sinus of Valsalva rarely arise from the left aortic sinus. We present the clinical features and surgical correction of this rare anomaly along with a short discussion of these congenital malformations. PMID:23439356

  6. Attenuation characteristics of ground motions in northern China

    Institute of Scientific and Technical Information of China (English)

    黄玉龙; 赵兴权; 罗奇峰

    2002-01-01

    Four recently developed attenuation models are calibrated by using a very limited amount of strong motion data recorded in China. The research shows that the attenuation characteristics of the earthquake shaking in northern China are similar to those in the western US. The supporting evidence includes Q factors, preliminary results of kappa values, stress drop,shear wave velocity profile in the shallow earth crust, areas enclosed by the isoseismals of Modified Mercalli Intensity V. From these comparisons of different attenuation models, it is recommended that the Crouse and McGuire spectral attenuation model could possibly be used for northern China.

  7. Importance of Attenuation Correction (AC for Small Animal PET Imaging

    Directory of Open Access Journals (Sweden)

    Henrik H. El Ali

    2012-10-01

    Full Text Available The purpose of this study was to investigate whether a correction for annihilation photon attenuation in small objects such as mice is necessary. The attenuation recovery for specific organs and subcutaneous tumors was investigated. A comparison between different attenuation correction methods was performed. Methods: Ten NMRI nude mice with subcutaneous implantation of human breast cancer cells (MCF-7 were scanned consecutively in small animal PET and CT scanners (MicroPETTM Focus 120 and ImTek’s MicroCATTM II. CT-based AC, PET-based AC and uniform AC methods were compared. Results: The activity concentration in the same organ with and without AC revealed an overall attenuation recovery of 9–21% for MAP reconstructed images, i.e., SUV without AC could underestimate the true activity at this level. For subcutaneous tumors, the attenuation was 13 ± 4% (9–17%, for kidneys 20 ± 1% (19–21%, and for bladder 18 ± 3% (15–21%. The FBP reconstructed images showed almost the same attenuation levels as the MAP reconstructed images for all organs. Conclusions: The annihilation photons are suffering attenuation even in small subjects. Both PET-based and CT-based are adequate as AC methods. The amplitude of the AC recovery could be overestimated using the uniform map. Therefore, application of a global attenuation factor on PET data might not be accurate for attenuation correction.

  8. [Usefulness of attenuation correction with transmission source in myocardial SPECT].

    Science.gov (United States)

    Murakawa, Keizo; Katafuchi, Tetsuro; Nishimura, Yoshihiro; Enomoto, Naoyuki; Sago, Masayoshi; Oka, Hisashi

    2006-01-20

    Attenuation correction in SPECT has been used for uniformly absorptive objects like the head. On the other hand, it has seldom been applied to nonuniform absorptive objects like the heart and surrounding lungs because of the difficulty and inaccuracy of data processing. However, since attenuation correction using a transmission source recently became practical, we were able to apply this method to a nonuniform absorptive object. Therefore, we evaluated the usefulness of this attenuation correction system with a transmission source in myocardial SPECT. The dose linearity, defect/normal ratio using a myocardial phantom, and myocardial count distribution in clinical cases was examined with and without the attenuation correction system. We found that all data processed with attenuation correction were better than those without attenuation correction. For example, in myocardial count distribution, while there was a difference between men and women without attenuation correction, which was considered to be caused by differences in body shape, after processing with attenuation correction, myocardial count distribution was almost the same in all cases. In conclusion, these results suggested that attenuation correction with a transmission source was useful in myocardial SPECT.

  9. Variation of Seismic Coda Wave Attenuation in the Garhwal Region, Northwestern Himalaya

    Science.gov (United States)

    Tripathi, Jayant N.; Singh, Priyamvada; Sharma, Mukat L.

    2012-01-01

    Seismic coda wave attenuation ( Q_{text{c}}^{ - 1} ) characteristics in the Garhwal region, northwestern Himalaya is studied using 113 short-period, vertical component seismic observations from local events with hypocentral distance less than 250 km and magnitude range between 1.0 to 4.0. They are located mainly in the vicinity of the Main Boundary Thrust (MBT) and the Main Central Thrust (MCT), which are well-defined tectonic discontinuities in the Himalayas. Coda wave attenuation ( Q_{text{c}}^{ - 1} ) is estimated using the single isotropic scattering method at central frequencies 1.5, 3, 5, 7, 9, 12, 16, 20, 24 and 28 Hz using several starting lapse times and coda window lengths for the analysis. Results show that the ( Q_{text{c}}^{ - 1} ) values are frequency dependent in the considered frequency range, and they fit the frequency power law ( Q_{text{c}}^{ - 1} left( f right) = Q0^{ - 1} f^{ - n} ). The Q 0 ( Q c at 1 Hz) estimates vary from about 50 for a 10 s lapse time and 10 s window length, to about 350 for a 60 s lapse time and 60 s window length combination. The exponent of the frequency dependence law, n ranges from 1.2 to 0.7; however, it is greater than 0.8, in general, which correlates well with the values obtained in other seismically and tectonically active and highly heterogeneous regions. The attenuation in the Garhwal region is found to be lower than the Q {c/-1} values obtained for other seismically active regions of the world; however, it is comparable to other regions of India. The spatial variation of coda attenuation indicates that the level of heterogeneity decreases with increasing depth. The variation of coda attenuation has been estimated for different lapse time and window length combinations to observe the effect with depth and it indicates that the upper lithosphere is more active seismically as compared to the lower lithosphere and the heterogeneity decreases with increasing depth.

  10. Effects of Substrates with Different Dielectric Parameters on Left-Handed Frequency of Left-Handed Materials

    Institute of Scientific and Technical Information of China (English)

    QUAN Bao-Gang; LI Chao; SUI Qiang; LI Jun-Jie; LIU Wu-Ming; LI Fang; GU Chang-Zhi

    2005-01-01

    @@ Wedge-shaped left-handed materials (LHMs) with split ring resonators and wires structures are fabricated by photolithography and lift-off techniques, and the variation of left-handed frequency induced by substrates with different dielectric parameters is investigated. The Snell refraction experiments of the LHM samples are carried out on an angular resoled microwave spectrometer, and the results indicate that the left-handed frequencies of the LHMs shifted downward from 10.57 GHz to 9.74 GHz when the dielectric parameters of the LHM substrates increase from 3.7 to 4.8. Moreover, the finite difference time domain method is used to simulate the microwave transmission properties of the left-handed materials with different substrates, and the experimental results are in agreement with the numerical simulation results. In addition, the reason for the shifting of the left-handedfrequency of the LHMs is discussed theoretically.

  11. Enhanced Attenuation Technologies: Passive Soil Vapor Extraction

    Energy Technology Data Exchange (ETDEWEB)

    Vangelas, K.; Looney, B.; Kamath, R.; Adamson, D.; Newell, C.

    2010-03-15

    Passive soil vapor extraction (PSVE) is an enhanced attenuation (EA) approach that removes volatile contaminants from soil. The extraction is driven by natural pressure gradients between the subsurface and atmosphere (Barometric Pumping), or by renewable sources of energy such as wind or solar power (Assisted PSVE). The technology is applicable for remediating sites with low levels of contamination and for transitioning sites from active source technologies such as active soil vapor extraction (ASVE) to natural attenuation. PSVE systems are simple to design and operate and are more cost effective than active systems in many scenarios. Thus, PSVE is often appropriate as an interim-remedial or polishing strategy. Over the past decade, PSVE has been demonstrated in the U.S. and in Europe. These demonstrations provide practical information to assist in selecting, designing and implementing the technology. These demonstrations indicate that the technology can be effective in achieving remedial objectives in a timely fashion. The keys to success include: (1) Application at sites where the residual source quantities, and associated fluxes to groundwater, are relatively low; (2) Selection of the appropriate passive energy source - barometric pumping in cases with a deep vadose zone and barrier (e.g., clay) layers that separate the subsurface from the atmosphere and renewable energy assisted PSVE in other settings and where higher flow rates are required. (3) Provision of sufficient access to the contaminated vadose zones through the spacing and number of extraction wells. This PSVE technology report provides a summary of the relevant technical background, real-world case study performance, key design and cost considerations, and a scenario-based cost evaluation. The key design and cost considerations are organized into a flowchart that dovetails with the Enhanced Attenuation: Chlorinated Organics Guidance of the Interstate Technology and Regulatory Council (ITRC). The PSVE

  12. Molecular mechanism of carvedilol in attenuating the reversion to fetal energy metabolism during cardiac hypertrophy development

    Institute of Scientific and Technical Information of China (English)

    胡琴; 李隆贵

    2003-01-01

    Objective: To explore the molecular regulation mechanism of carvedilol in attenuating the reversion back towards fetal energy metabolism during the development of cardiac hypertrophy induced by coarctation of abdominal aorta (CAA) in male Wistar rats. Methods: Hemodynamic and ventricular remodeling parameters, free fatty acid content in the serum were measured in the experimental animals at 16 weeks after the surgical CAA, the rats receiving carvedilol intervention (CAR) after CAA, and those with sham operation (SH). The expressions of muscle carnitine palmitoyltransferaseⅠ (M-CPTⅠ) and medium chain acyl-CoA dehydrogenase (MCAD) mRNA in the cardiac myocytes from every group were studied with RT-PCR. Results: Significant left ventricular hypertrophy were observed in the rats 16 weeks after coarctation operation (P<0.05), together with significant free fatty acids accumulation and downregulation of M-CPTⅠ and MCAD mRNA (P<0.05) in CAA group. Carvedilol at a dose of 30 mg/kg/d for 12 weeks inhibited the left ventricular hypertrophy induced by pressure overload and enhanced the gene expressions of rate-limiting enzyme (M-CPTⅠ) and key enzyme of fatty acid (MCAD) in the CAR group compared with CAA group (P<0.05). Conclusion: Pressure overload-induced hypertrophy in CAA rats causes the reversion back towards fetal enery metabolism, that is, downregulates the expressions of rate-limiting enzyme and key enzyme of fatty acid oxidation. The intervention therapy with carvedilol, a vasodilating alpha- and beta-adrenoreceptor antagonist, attenuates the reversion of the metabolic gene expression to fetal type through upregulating M-CPTⅠ and MCAD mRNA expressions. Thus, carvedilol may exert cardioprotective effects on heart failure by the mechanism of preserving the adult metabolic gene regulation.

  13. Association of arterial stiffness and electrocardiography-determined left ventricular hypertrophy with left ventricular diastolic dysfunction.

    Directory of Open Access Journals (Sweden)

    Po-Chao Hsu

    Full Text Available OBJECTIVES: Increased arterial stiffness is associated with left ventricular diastolic dysfunction (LVDD, but this association may be influenced by left ventricular (LV performance. Left ventricular hypertrophy (LVH is not only a significant determinant of LV performance, but is also correlated with LVDD. This study is designed to compare LV diastolic function among patients divided by brachial-ankle pulse wave velocity (baPWV and electrocardiography (ECG-determined LVH and to assess whether increased baPWV and ECG-determined LVH are independently associated with LVDD. METHODS: This cross-sectional study enrolled 270 patients and classified them into four groups according to the median value of baPWV and with/without ECG-determined LVH. The baPWV was measured using an ABI-form device. ECG-determined LVH was defined by Sokolow-Lyon criterion. LVDD was defined as impaired relaxation, pseudonormal, and restrictive mitral inflow patterns. Groups 1, 2, 3, and 4 were patients with lower baPWV and without ECG-determined LVH, lower baPWV but with ECG-determined LVH, higher baPWV but without ECG-determined LVH, and higher baPWV and with ECG-determined LVH respectively. RESULTS: Early diastolic mitral velocity (Ea was gradually decreased from group 1 to group 4 (p≦0.027. Patients in group 4 had the highest prevalence of LVDD (all p<0.001. After multivariate analysis, both baPWV and ECG-determined LVH were independent determinants of Ea (β = -0.02, P<0.001; β = -1.77, P<0.001 respectively and LVDD (odds ratio = 1.02, P = 0.011 and odds ratio = 3.53, P = 0.013 respectively. CONCLUSION: Our study showed the group with higher baPWV and ECG-determined LVH had the lowest Ea and highest prevalence of LVDD. In addition, both baPWV and ECG-determined LVH were independently associated with Ea and LVDD. Hence, assessment of arterial stiffness by baPWV and LVH by ECG may be useful in identifying the high risk group of LVDD.

  14. Definition of Genetically Distinct Attenuation Mechanisms in Naturally Virulence-Attenuated Listeria monocytogenes by Comparative Cell Culture and Molecular Characterization

    OpenAIRE

    Roberts, Angela; Chan, Yvonne; Wiedmann, Martin

    2005-01-01

    Listeria monocytogenes is a foodborne pathogen able to cause serious disease in humans and animals. Not all isolates are equally pathogenic, however, and several isolates have been characterized as naturally virulence attenuated. We sought to identify the genetic basis of natural virulence attenuation using cell culture assays and molecular techniques. By comparing the phenotypes of naturally virulence-attenuated isolates to those of defined virulence gene mutants in plaque, cytotoxicity, and...

  15. Left-sided gallbladder: Its clinical significance and imaging presentations

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To assess the importance of preoperative diagnosis and presentation of left-sided gallbladder using ultrasound (US), CT and angiography.METHODS: Retrospective review of 1482 patients who underwent enhanced CT scanning was performed. Left-sided gallbladder was diagnosed if a right-sided ligamentum teres was present. The image presentations on US, CT and angiography were also reviewed.RESULTS: Left-sided gallbladder was diagnosed in nine patients. The associated abnormalities on CT imaging included portal vein anomalies, absence of umbilical portion of the portal vein in the left lobe of the liver,club-shaped portal vein in the right lobe of the liver, and difficulty in identifying segment Ⅳ. Angiography in six of nine patients demonstrated abnormal portal venous system (trifurcation type in four of six patients). The main hepatic arteries followed the portal veins in all six patients. The segment Ⅳ artery was identified in four of six patients using angiography, although segment Ⅳ was difficult to define on CT imaging. Hepatectomy was performed in three patients with concomitant liver tumor and the diagnosis of left-sided gallbladder was confirmed intraoperatively.CONCLUSION: Left-sided gallbladder is an important clinical entity in hepatectomy due to its associated portal venous and biliary anomalies. It should be considered in US, CT and angiography images that demonstrate no definite segment IV, absence of umbilical portion of the portal vein in the left lobe, and club-shaped right anterior portal vein.

  16. Left ventricular systolic and diastolic function in hyperthyroidism

    Energy Technology Data Exchange (ETDEWEB)

    Friedman, M.J.; Okada, R.D.; Ewy, G.A.; Hellman, D.J.

    1982-12-01

    In order to assess the effect of hyperthyroidism on systolic and diastolic function of the left ventricle, M-mode echocardiograms and systolic time intervals were obtained in 13 patients while they were clinically hyperthyroid and again when they were euthyroid following radioactive iodine therapy. Echocardiographic tracings of the septum and left ventricular posterior wall were digitized and analyzed to provide the maximum velocity of shortening and maximum velocity of lengthening. These velocities were normalized for left ventricular diastolic dimension. The left ventricular minor axis fractional shortening and the normalized maximum velocity of shortening were both increased during the hyperthyroid state. The normalized maximum velocity of lengthening, a measure of diastolic left ventricular function, was also increased during the hyperthyroid state when compared to the euthyroid state. The preejection period index and the preejection period/left ventricular ejection time ratio were lower when the patients were hyperthyroid than when they were euthyroid. These data confirm the increased inotropic state and demonstrated increased diastolic relaxation velocities of the hyperthyroid left ventricle.

  17. [Pseudoaneurysm of the left ventricle: a report of 2 cases].

    Science.gov (United States)

    Pomini, G; Lupia, M; Milano, A; Gribaldo, R

    1993-03-01

    Two cases of left ventricular pseudoaneurysm following myocardial infarction are presented. In the first patient a two-dimensional echocardiography study revealed a small posterior echo-free space that appeared to communicate with the left ventricle through a small defect in the left ventricular posterior wall. Conventional Doppler echocardiography and colour flow imaging demonstrated flow between the left ventricle and the paraventricular chamber. In the other patient, the same study detected an enormous false aneurysm. We found a large extramyocardial echo-free space within the pericardial cavity. The site of this space was posterolateral and communicating with the left ventricular cavity. Cardiac catheterization and surgery confirmed the diagnosis. A postoperative echocardiographic study demonstrated a persistent but smaller saccular echo-free space and a residual shunt through one site of repair in the first patient; in the other, after surgical treatment there was no residual flow, but a left ventricular dysfunction was detected. Two dimensional and color Doppler echocardiography is the best technique among the noninvasive methods, for detecting and following up left ventricular pseudoaneurysms. PMID:8325466

  18. The role of the left putamen in multilingual language production.

    Science.gov (United States)

    Abutalebi, Jubin; Della Rosa, Pasquale Anthony; Gonzaga, Anna Kaarina Castro; Keim, Roland; Costa, Albert; Perani, Daniela

    2013-06-01

    Subcortical structures are a key component of bilingual language processing. For instance, there is now evidence that the head of the left caudate is involved in controlling languages in bilingual individuals. On the other hand, the left putamen is hypothesized to be involved in articulatory processes but little is known on its engagement in bilingual language processing. Here, our hypothesis was that the left putamen of multilinguals is engaged when producing words in the less proficient language. We investigated this issue with event-related functional Magnetic Resonance (er-fMRI) in a group of multilinguals (n = 14) and in monolinguals (n = 14) during a picture-naming task. Further, we hypothesized increased grey matter density in the left putamen as an effect of experience since multilinguals constantly face a major articulatory load (i.e., speaking multiple languages) during life. To test these hypotheses we measured structural differences between multilinguals and monolinguals using voxel-based morphometry (VBM). Our results indicate that multilinguals have increased activation in the left putamen for a non-native language, but only if they are not highly proficient in that language. In addition, we found increased grey matter density in the left putamen of multilinguals compared to monolinguals. These findings highlight that the multilingual brain handles a complex articulatory repertoire (i.e., dealing with multiple languages) by inducing structural plasticity in the left putamen.

  19. Turbulence attenuation by large neutrally buoyant particles

    CERN Document Server

    Cisse, Mamadou; Gibert, Mathieu; Bodenschatz, Eberhard; Bec, Jeremie

    2015-01-01

    Turbulence modulation by inertial-range-size, neutrally-buoyant particles is investigated experimentally in a von K\\'arm\\'an flow. Increasing the particle volume fraction $\\Phi_\\mathrm{v}$, maintaining constant impellers Reynolds number attenuates the fluid turbulence. The inertial-range energy transfer rate decreases as $\\propto\\Phi_\\mathrm{v}^{2/3}$, suggesting that only particles located on a surface affect the flow. Small-scale turbulent properties, such as structure functions or acceleration distribution, are unchanged. Finally, measurements hint at the existence of a transition between two different regimes occurring when the average distance between large particles is of the order of the thickness of their boundary layers.

  20. Attenuation of neutrons through ducts and labyrinths

    CERN Document Server

    Mauro, Egidio

    2009-01-01

    Monte Carlo simulations have been performed for the attenuation of neutron radiation produced at proton accelerators through ducts and labyrinths of various design, and the results are compared with the predictions made by analytical expressions available in the literature. The results show that the so-called universal transmission curves are an appropriate and simple tool applicable in many situations, when the radiation source is not in direct view of the duct mouth. This is not the case for point sources located in front of the duct. The simulations showed that it is not possible to apply the same models because the transmission factor is strongly dependent on the cross-sectional area of the duct. A universal expression has been derived to estimate the neutron transmission through a straight duct of length d and cross-sectional area A in direct view of the source, which only depends on A and on a small set of numerical coefficients.

  1. Attenuation of Shocks through Porous Media

    Science.gov (United States)

    Lind, Charles A.; Cybyk, Bohdan Z.; Boris, Jay P.

    1998-11-01

    Structures designed to mitigate the effects of blast and shock waves are important for both accidental and controlled explosions. The net effect of these mitigating structures is to reduce the strength of the transmitted shock thereby reducing the dynamic pressure loading on nearby objects. In the present study, the attenuation of planar blast and shock waves by passage through structured media is numerically studied with the FAST3D model. The FAST3D model is a state-of-the-art, portable, three-dimensional computational fluid dynamics model based on Flux-Corrected Transport and uses the Virtual Cell Embedding algorithm for simulating complex geometries. The effects of media placement, spacing, orientation, and area blockage are parametrically studied to enhance the understanding of the complex processes involved and to determine ways to minimize the adverse effects of these blast waves.

  2. Core disgust is attenuated by ingroup relations.

    Science.gov (United States)

    Reicher, Stephen D; Templeton, Anne; Neville, Fergus; Ferrari, Lucienne; Drury, John

    2016-03-01

    We present the first experimental evidence to our knowledge that ingroup relations attenuate core disgust and that this helps explain the ability of groups to coact. In study 1, 45 student participants smelled a sweaty t-shirt bearing the logo of another university, with either their student identity (ingroup condition), their specific university identity (outgroup condition), or their personal identity (interpersonal condition) made salient. Self-reported disgust was lower in the ingroup condition than in the other conditions, and disgust mediated the relationship between condition and willingness to interact with target. In study 2, 90 student participants smelled a sweaty target t-shirt bearing either the logo of their own university, another university, or no logo, with either their student identity or their specific university identity made salient. Walking time to wash hands and pumps of soap indicated that disgust was lower where the relationship between participant and target was ingroup rather than outgroup or ambivalent (no logo). PMID:26903640

  3. Gas sensor with attenuated drift characteristic

    Science.gov (United States)

    Chen, Ing-Shin [Danbury, CT; Chen, Philip S. H. [Bethel, CT; Neuner, Jeffrey W [Bethel, CT; Welch, James [Fairfield, CT; Hendrix, Bryan [Danbury, CT; Dimeo, Jr., Frank [Danbury, CT

    2008-05-13

    A sensor with an attenuated drift characteristic, including a layer structure in which a sensing layer has a layer of diffusional barrier material on at least one of its faces. The sensor may for example be constituted as a hydrogen gas sensor including a palladium/yttrium layer structure formed on a micro-hotplate base, with a chromium barrier layer between the yttrium layer and the micro-hotplate, and with a tantalum barrier layer between the yttrium layer and an overlying palladium protective layer. The gas sensor is useful for detection of a target gas in environments susceptible to generation or incursion of such gas, and achieves substantial (e.g., >90%) reduction of signal drift from the gas sensor in extended operation, relative to a corresponding gas sensor lacking the diffusional barrier structure of the invention

  4. Attenuation of ultrasonic waves in rolled metals

    Science.gov (United States)

    Yang, Liyong; Turner, Joseph A.

    2004-12-01

    Scattering of ultrasonic waves in polycrystals with texture is studied in this article. The attenuations of the three wave modes are determined as a function of dimensionless frequency and propagation direction, respectively, for given orientation distribution coefficients (ODCs). The calculation is done in the case of a statistically orthorhombic sample made up of cubic crystallites. The wave propagation and scattering model is formulated by the Dyson equation using an anisotropic Green's function approach. Within the limits of the first-order smoothing approximation, the Dyson equation is solved in the spatial Fourier transform domain. The results presented are shown to be directional dependent, frequency dependent, and especially dependent on the texture coefficients (ODCs) for the quasilongitudinal and two quasishear waves. The theoretical results presented may be used to improve the understanding of the microstructure during recrystallization processes. .

  5. Attenuation of species abundance distributions by sampling.

    Science.gov (United States)

    Shimadzu, Hideyasu; Darnell, Ross

    2015-04-01

    Quantifying biodiversity aspects such as species presence/ absence, richness and abundance is an important challenge to answer scientific and resource management questions. In practice, biodiversity can only be assessed from biological material taken by surveys, a difficult task given limited time and resources. A type of random sampling, or often called sub-sampling, is a commonly used technique to reduce the amount of time and effort for investigating large quantities of biological samples. However, it is not immediately clear how (sub-)sampling affects the estimate of biodiversity aspects from a quantitative perspective. This paper specifies the effect of (sub-)sampling as attenuation of the species abundance distribution (SAD), and articulates how the sampling bias is induced to the SAD by random sampling. The framework presented also reveals some confusion in previous theoretical studies. PMID:26064626

  6. ANGIOGRAPHIC PROFILE OF LEFT MAIN CORONARY ARTERY (LMCA STENOSIS

    Directory of Open Access Journals (Sweden)

    Malladi Srinivasa

    2015-02-01

    Full Text Available Among patients with coronary artery disease, left coronary artery (LMCA stenosis is the dangerous form of coronary arterial involvement, associated with increased mortality and morbidity unless immediate intervention is done. The gold standard treatment for left main coronary artery (LMCA stenosis is the emergency coronary artery bypass grafting to its branches, left anterior descending artery (LAD, and left circumflex artery (LCX. Of percutaneous intervention in the form of angioplasty and stenting of left main coronary artery are increasingly done. The anatomy and the site of stenosi s in the left main coronary artery determine the management option. In this context, the involvement of left main coronary artery and its anatomical pattern are important in deciding management options. AIM: To study the angiographic profile of significant Left main coronary artery (LMCA stenosis among the patients who underwent coronary angiography. METHODS: A total of 1911 cases of significant coronary arterial disease, who underwent coronary angiography a t King George Hospital, Visakhapatnam were studied in the present study and their coronary angiograms were analysed with respect to the pattern of involvement. RESULTS: of the 1911 cases of coronary artery disease, 118 patients have left main coronary arte ry disease. M/F ratio is 93/25. Of them 68.4% are hypertensive, 41.5 % are diabetics, 34.7% are smokers. Mean age of presentation was 59 yrs. Isolated LMCA involvement is seen in 5, associated with single vessel disease in 9, double vessel disease in 12 an d triple vessel diseases in 93. Ostio - proximal involvement is seen in 21, mid segment involvement in 13, distal – bifurcation involvement in 93 and total occlusion of LMCA in 1 case. CONCLUSION: Significant LMCA involvement is seen in 6.1%. In majority of c ases, it is associated with triple vessel disease and distal bifurcation is the commonest site involved.

  7. A miniaturized reconfigurable broadband attenuator based on RF MEMS switches

    Science.gov (United States)

    Guo, Xin; Gong, Zhuhao; Zhong, Qi; Liang, Xiaotong; Liu, Zewen

    2016-07-01

    Reconfigurable attenuators are widely used in microwave measurement instruments. Development of miniaturized attenuation devices with high precision and broadband performance is required for state-of-the-art applications. In this paper, a compact 3-bit microwave attenuator based on radio frequency micro-electro-mechanical system (RF MEMS) switches and polysilicon attenuation modules is presented. The device comprises 12 ohmic contact MEMS switches, π-type polysilicon resistive attenuation modules and microwave compensate structures. Special attention was paid to the design of the resistive network, compensate structures and system simulation. The device was fabricated using micromachining processes compatible with traditional integrated circuit fabrication processes. The reconfigurable attenuator integrated with RF MEMS switches and resistive attenuation modules was successfully fabricated with dimensions of 2.45  ×  4.34  ×  0.5 mm3, which is 1/1000th of the size of a conventional step attenuator. The measured RF performance revealed that the attenuator provides 10-70 dB attenuation at 10 dB intervals from 0.1-20 GHz with an accuracy better than  ±1.88 dB at 60 dB and an error of less than 2.22 dB at 10 dB. The return loss of each state of the 3-bit attenuator was better than 11.95 dB (VSWR  <  1.71) over the entire operating band.

  8. Radionuclide assessment of left ventricular function following cardiac surgery

    Energy Technology Data Exchange (ETDEWEB)

    Howe, W.R.; Jones, R.H.; Sabiston, D.C. Jr.

    1976-01-01

    Use of a high count-rate gamma scintillation camera permits the noninvasive assessment of left ventricular function by nuclear angiocardiography. Counts recorded from the region of the left ventricle at 50- or 100-msec intervals during the first transit of an intravenously administered bolus of radioisotope produce a high-fidelity indicator-dilution curve. Count fluctuations reflect left ventricular volume changes during the cardiac cycle and permit measurement of dv/dt, ejection fraction, mean transit time, and wall motion of this chamber. The present study evaluates (1) the accuracy of this technique compared to standard biplane cineangiography and (2) its usefulness in evaluating patients after cardiac surgery.

  9. Primary left ventricular hydatid cyst in a child: case report

    Energy Technology Data Exchange (ETDEWEB)

    Turkvatan, A. [Turkiye Yuksek Ihtisas Hospital, Dept. of Radiology, Ankara (Turkey); Yelgec, N.S. [Turkiye Yuksek Ihtisas Hospital, Dept. of Cardiology, Ankara (Turkey); Calikoglu, U.; Olcer, T. [Turkiye Yuksek Ihtisas Hospital, Dept. of Radiology, Ankara (Turkey)

    2000-12-01

    The most common cause of echinococcosis in humans is Echinococcus granulosus. Although hydatid cyst is most frequently localized in liver (more than 65% of cases) and lung (25%) by means of portal and systemic circulation, it may involve other tissues and organs. Cardiac hydatid cysts account for only 0.5%-2% of all hydatid cysts, even in endemic areas. Of all cardiac hydatid cysts, the left ventricle accounts for 60%, right ventricle 10%, pericardium 7%, pulmonary artery 6%, left atrial appendage 6%, and interventricular septum 4%. We report the case of a myocardial hydatid cyst of the left ventricle in a 9-year-old boy. (author)

  10. Left paraduodenal hernia presenting as recurrent small bowel obstruction

    Institute of Scientific and Technical Information of China (English)

    Yu-Min Huang; Andy Shau-Bin Chou; Yung-Kang Wu; Chao-Chuan Wu; Ming-Che Lee; Haw-Tzong Chen; Yao-Jen Chang

    2005-01-01

    Internal herniation of the small bowel is a relatively rare cause of intestinal obstruction. Left paraduodenal hernia resulting from abnormal rotation of the midgut during embryonic development is the most common form of congenital internal hernia. We report our experience in the diagnosis and management of a young male with left paraduodenal hernia presenting as recurrent intestinal obstruction. Correct preoperative diagnosis of left paraduodenal hernia had been difficult due to non-specific clinical presentations, but the advent of modern imaging technology makes early and correct diagnosis possible. Due to the risk of obstruction and strangulation, surgical treatment is indicated; however,timely intervention increases the likelihood of a favorable outcome.

  11. Left ventricular thrombus associated with arteriovenous extra corporeal membrane oxygenation

    Science.gov (United States)

    Makdisi, George; Hashmi, Zubair A.; Wozniak, Thomas C.

    2015-01-01

    Extra corporeal membrane oxygenation (ECMO) has remarkably progressed over the recent years. It has become an invaluable tool in the care of adults and pediatric patients with severe cardiogenic shock. At the initiation of ECMO support, the left ventricular contractility is profoundly impaired. Inadequate right ventricular drainage and bronchial circulation can lead to left ventricular distension, with potential deleterious consequences, ranging from inadequate myocardial rest, pulmonary edema, or intracardiac clot formation. Therefore, it is of extreme importance to ensure an adequate left ventricular drainage. Here we present a case of LV thrombus developed while the patient is on central venoarterial (VA) ECMO. PMID:26716054

  12. Left ventricular thrombus associated with arteriovenous extra corporeal membrane oxygenation.

    Science.gov (United States)

    Makdisi, George; Hashmi, Zubair A; Wozniak, Thomas C; Wang, I-Wen

    2015-11-01

    Extra corporeal membrane oxygenation (ECMO) has remarkably progressed over the recent years. It has become an invaluable tool in the care of adults and pediatric patients with severe cardiogenic shock. At the initiation of ECMO support, the left ventricular contractility is profoundly impaired. Inadequate right ventricular drainage and bronchial circulation can lead to left ventricular distension, with potential deleterious consequences, ranging from inadequate myocardial rest, pulmonary edema, or intracardiac clot formation. Therefore, it is of extreme importance to ensure an adequate left ventricular drainage. Here we present a case of LV thrombus developed while the patient is on central venoarterial (VA) ECMO. PMID:26716054

  13. Evaluation of left ventricular volumes measured by magnetic resonance imaging

    DEFF Research Database (Denmark)

    Møgelvang, J; Thomsen, C; Mehlsen, J;

    1986-01-01

    Left ventricular end-diastolic and end-systolic volumes were determined in 17 patients with different levels of left ventricular function by magnetic resonance imaging (MRI). A 1.5 Tesla Magnet was used obtaining ECG triggered single and multiple slices. Calculated cardiac outputs were compared...... was seen when the single slice technique was used (r = 0.06, p greater than 0.80). The results indicate that MRI is a reliable method for left ventricular volume determination when the multislice technique is used....

  14. Anomalous Positive Refraction in an Anisotropic Left-Handed Medium

    Institute of Scientific and Technical Information of China (English)

    HU Wei; LUO Hai-Lu; CAO Jing-Xiao

    2005-01-01

    @@ We investigate the refraction phenomena of extraordinary light at a planar interface associated with a uniaxial left-handed medium. It is found that the anomalous positive refraction can occur at the interface from anisotropic right-handed medium to a uniaxially anisotropic left-handed medium. When the optical axis of a uniaxial left-handed medium is not normal or parallel to the interface, the refraction of the Poynting vector for the extraordinary waves can be either positive or negative depending on the incident angles, while the refraction of the wave vector is always negative. The physical essential of the anomalous positive refraction results from the anisotropy of uniaxial crystals.

  15. Are all left supraclavicular lymphadenopathies Virchow's? A retrospective study of 320 left cervical lymphadenopathy

    Directory of Open Access Journals (Sweden)

    Veena Raja

    2016-01-01

    Full Text Available Background: Cervical Lymphadenopathy is one of the commonest and sometimes only clinical finding for a benign and malignant lesion. Fine needle aspiration cytology (FNAC is a simple, safe, rapid and inexpensive method for establishing the diagnosis of lesions. Metastasis is more common in cervical lymph node and enlarged cervical nodes in an elderly patient must be considered as metastatic until proved otherwise. Methods: Retrospectively, 320 cases of left cervical lymph node FNAC were collected from five years record (May 2010 - June 2014 at Sri Devaraj Urs Medical College, Tamaka, Kolar. Review of all cytological reports were done according to standard guidelines and the morphological features of all non-neoplastic and neoplastic lesions were analysed. Results: Out of 320 cases 33% showed reactive lymphadenitis, 29% showed metastatic deposits, 14% showed features of granulomatous and necrotizing lymphadenitis, 9% were tuberculous lymphadenitis. In the present study, reactive lymphadenitis was the most common cause of enlarged lymph nodes followed by metastatic deposits. Squamous cell carcinoma is the most common metastatic lesions of lymphnode and comprise of 65% of the cases. Out of 62 cases of SCC 74% were keratinized, 16% were non keratinized, 29% cases showed granulomas. Non keratinization, presence of granuloma, plasma cells and eosinophils favours metastasis from nasopharyngeal carcinoma. Keratinization favours squamous cell carcinoma and absence of eosinophils and plasma cells in the background favors SCC metastasis from other sites. Conclusion: The present study highlight the usefulness of FNAC in left cervical lymphadenopathy where metastasis is common. Thus the knowledge about the cytological features and patterns will help the clinician to detect the respective cases early for investigations and treatment.

  16. Fatal stroke after completion pneumonectomy for torsion of left upper lobe following left lower lobectomy

    Directory of Open Access Journals (Sweden)

    Apostolakis Efstratios

    2006-09-01

    Full Text Available Abstract Background The lobar torsion after lung surgery is a rare complication with an incidence of 0.09 to 0.4 %. It may occur after twisting of the bronchovascular pedicle of the remaining lobe after lobectomy, usually on the right side. The 180-degree rotation of the pedicle produces an acute obstruction of the lobar bronchus (atelectasis and of the lobar vessels as well. Without prompt treatment it progresses to lobar ischemia, pulmonary infarction and finally fatal gangrene. Case Presentation A 62 years old female patient was admitted for surgical treatment of lung cancer. She underwent elective left lower lobectomy for squamous cell carcinoma (pT2 N0. The operation was unremarkable, and the patient was extubated in the operating room. After eight hours the patient established decrease of pO2 and chest x-ray showed atelectasis of the lower lobe. To establish diagnosis, bronchoscopy was performed, demonstrating obstructed left lobar bronchus. The patient was re-intubated, and admitted to the operating room where reopening of the thoracotomy was performed. Lobar torsion was diagnosed, with the diaphragmatic surface of the upper lobe facing in an anterosuperior orientation. A completion pneumonectomy was performed. At the end of the procedure the patient developed a right pupil dilatation, presumably due to a cerebral embolism. A subsequent brain angio-CT scan established the diagnosis. She died at the intensive care unit 26 days later. Conclusion The thoracic surgeon should suspect this rare early postoperative complication after any thoracic operation in every patient with atelectasis of the neighboring lobe. High index of suspicion and prompt diagnosis may prevent catastrophic consequences, such as, infarction or gangrene of the pulmonary lobe. During thoracic operations, especially whenever the lung or lobe hilum is full mobilized, fixation of the remaining lobe may prevent this life threatening complication.

  17. Exercise training attenuates the pressor response evoked by peripheral chemoreflex in rats with heart failure.

    Science.gov (United States)

    Calegari, Leonardo; Mozzaquattro, Bruna B; Rossato, Douglas D; Quagliotto, Edson; Ferreira, Janaina B; Rasia-Filho, Alberto; Dal Lago, Pedro

    2016-09-01

    The effects of exercise training (ExT) on the pressor response elicited by potassium cyanide (KCN) in the rat model of ischemia-induced heart failure (HF) are unknown. We evaluated the effects of ExT on chemoreflex sensitivity and its interaction with baroreflex in rats with HF. Wistar rats were divided into four groups: trained HF (Tr-HF), sedentary HF (Sed-HF), trained sham (Tr-Sham), and sedentary sham (Sed-Sham). Trained animals underwent to a treadmill running protocol for 8 weeks (60 m/day, 5 days/week, 16 m/min). After ExT, arterial pressure (AP), baroreflex sensitivity (BRS), peripheral chemoreflex (KCN: 100 μg/kg body mass), and cardiac function were evaluated. The results demonstrate that ExT induces an improvement in BRS and attenuates the pressor response to KCN relative to the Sed-HF group (P ExT in HF rats (P ExT induced a reduction in left ventricular end-diastolic pressure and pulmonary congestion compared with the Sed-HF group (P ExT improves cardiac function and BRS and attenuates the pressor response evoked by KCN in HF rats. PMID:27295522

  18. Inhibition of Uncoupling Protein 2 Attenuates Cardiac Hypertrophy Induced by Transverse Aortic Constriction in Mice

    Directory of Open Access Journals (Sweden)

    Xiao-Bing Ji

    2015-07-01

    Full Text Available Background: Uncoupling protein 2 (UCP2 is critical in regulating energy metabolism. Due to the significant change in energy metabolism of myocardium upon pressure overload, we hypothesize that UCP2 could contribute to the etiology of cardiac hypertrophy. Methods: Adult male C57BL/6J mice were subjected to pressure overload by using transverse aortic constriction (TAC, and then received genipin (a UCP2 selective inhibitor; 25 mg/kg/d, ip or vehicle for three weeks prior to histologic assessment of myocardial hypertrophy. ATP concentration, ROS level, and myocardial apoptosis were also examined. A parallel set of experiments was also conducted in UCP2-/- mice. Results: TAC induced left ventricular hypertrophy, as reflected by increased ventricular weight/thickness and increased size of myocardial cell (vs. sham controls. ATP concentration was decreased; ROS level was increased. Apoptosis and fibrosis markers were increased. TAC increased mitochondrial UCP2 expression in the myocardium at both mRNA and protein levels. Genipin treatment attenuated cardiac hypertrophy and the histologic/biochemical changes described above. Hypertrophy and associated changes induced by TAC in UCP2-/- mice were much less pronounced than in WT mice. Conclusions: Blocking UCP2 expression attenuates cardiac hypertrophy induced by pressure overload.

  19. Mosaic pattern of lung attenuation on thin-section CT : review of 31 cases

    International Nuclear Information System (INIS)

    To correlate radiologic findings with clinical findings in patients with a mosaic pattern of lung attenuation, as seen on thin-section CT. Materials and Methods : Thirty-one cases in which a mosaic pattern of lung attenuation was detected on combined expiratory and inspiratory scans of thin-section CT were retrospectively analyzed. Cases involving infiltrative lung disease were excluded. Both thin-section CT and clinical findings we reanalyzed and the relationship between the extent of the area of hyperlucency -as seen on expiratory scan- and physiologic parameters was evaluated. The subjects were 10 men and 21 women ranged in age from 25 to 76 (mean 50)years. Results : Twenty-nine patients with small airway disease, [chronic bronchitis and/or bronchiolitis(n=11),bronchiectasis(n=8), bronchial asthma(n=8), mycoplasmic pneumonitis(n=1) and hypersensitive pneumonitis(n=1),] and two patients with pulmonary vascular disease, [chronic pulmonary thromboembolism(n=1) and stenosis of the left upper pulmonary artery(n=1)] were included in our study. Commonly associated thin-section CT findings in the cases involving small airway disease(n=29) were bronchial wall thickening(n=25), nodular opacity(n=25), bronchial and bronchiolar dilatation(n=20) and small branching opacity(n=16). These findings were not observed in two patients with pulmonary vascular disease, though bronchial wall thickening was seen in the patient with chronic pulmonary thromboembolism. At expiratory scan level, there was statistical correlation between FEV1/FVC and the number of pulmonary segments(r= 0.982, p0.05). Conclusion: The mosaic pattern of lung attenuation seen on thin-section CT is indicative of various diseases, involving small airways such as bronchiolitis, bronchitis, bronchiectasis and bronchial asthma, and vascular lung disease. Bronchial wall thickening and nodular opacity can be associated with small airway diseases

  20. Conduction between left superior pulmonary vein and left atria and atria fibrillation under cervical vagal trunk stimulation.

    Directory of Open Access Journals (Sweden)

    Hou Yuemei

    2009-11-01

    Full Text Available Objective: The effect of cervical vagal trunk stimulation on conduction between left superior pulmonary vein and left atria and atria fibrillation have not been systematically studied. We attempted to investigate the electrical conduction between LA and LSPV in dogs with cervical vagal trunk stimulation and evaluate the possible underline substrates for local reentry and initiation and maintenance of AF. Methods: 12 mongrel dogs (18-25 kg underwent cervical vagal trunk stimulation at high-frequency (60 ms, 1-4V to produce sinus arrest lasting >2 seconds,complete atrioventricular AV blocking or the sinus rate decreasing more than 50%. Left lateral thoracotomy was performed and the heart was exposed in a pericardial cradle. The HRA, LAA, PV-LAJ, LSPVm and LSPVd was locally stimulated (100 ms, 2-8V. ERP of HRA, LAA, PV-LAJ and within LSPV, ERP heterogeneity within LSPV and conduction between left superior pulmonary vein and left atria and atrial fibrillation inducing rate with vagal response was analyzed. Results: 1. During cervical vagal stimulation, the heart rate was reduced significantly from baseline 156±34 bpm to 75±34 bpm (p Conclusion: Our study strongly suggested that fast ectopic beating, abnormal vagal nerve activation as well as remodeling conduction between left superior pulmonary vein and left atria might are the common underline substrates for local reentry and AF initiation and maintenance.

  1. Periportal low-attenuation: a CT sign of lymphatic obstruction

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang Hoon; Kim, Chong Soo; Yang, Doo Hyun; Lee, Sang Yong; Lee, Young Whan; Chung, Gyung Ho; Han, Young Min; Sohn, Myung Hee; Choi, Ki Chul [Chonbuk National University College of Medicine, Jeonju (Korea, Republic of)

    1995-07-15

    Periportal low attenuation, defined as a low attenuation rim around the portal vein and its branches which is seen on contrast material-enhanced CT scans, has been described in a variety of conditions. We tried to document that lymphatic obstruction is one of the major cause of periportal low attenuation. We retrospectively analyzed 57 cases of periportal low attenuation of abdominal CT scans and also reviewed the surgical records in 32 cases. Lymph node enlargement in the hepatoduodenal ligament which is a main lymphatic channel from the liver were analyzed the calculated the ratio of the transeverse diameter between the inferior vena cava and the aorta at the level of right adrenal gland. After complete surgical interruption of the lymphatic drainage from the liver in a dog, follow up CT scans were obtained and correlated with pathologic findings. Fifty patients (88%) had underlying disease which could cause impairment of lymphatic drainage. Periportal low attenuation was identified in several clinical conditions, including surgical lymph node dissection, lymphadenopathy in the hepatoduodenal ligament, blunt trauma. In animal model, CT scan showed prominent periportal low attenuation at 5 days after surgery. Histologic examination revealed numerous dilated lymphatic vessels and a marked lymphedema in the connective tissues surrounding the portal vein and its major branches. One of the major cause of periportal low attenuation was impaired lymphatic drainage and periportal low attenuation corresponding to the numerous dilated lymphatic vessels and a marked lymphedema in the connective tissues surrounding the portal vein and its major branches.

  2. Attenuation law of explosive stress wave in damaged rock mass

    Institute of Scientific and Technical Information of China (English)

    CHEN Shi-hai; CUI Xin-zhuang

    2001-01-01

    The attenuation regularity of explosion stress waves in damaged rocks is discussed according to physical and geometric attenuation of waves in this pa per. The relation between numerical decrement and damaged parameter is given and the results have an important significance to design and control blasting effec t accurately in a concrete rock.

  3. Attenuation law of explosive stress wave in damaged rock mass

    Institute of Scientific and Technical Information of China (English)

    陈士海; 崔新壮

    2001-01-01

    The attenuation regularity of explosion stress waves in damaged rocks is discussed according to physical and geometric attenuation of waves in this paper. The relation between numerical decrement and damaged parameter is given and the results have an important significance to design and control blasting effect accurately in a concrete rock.

  4. 16 CFR 1203.17 - Impact attenuation test.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Impact attenuation test. 1203.17 Section... SAFETY STANDARD FOR BICYCLE HELMETS The Standard § 1203.17 Impact attenuation test. (a) Impact test... the acceleration of the test headform during impact. Acceleration is measured with a...

  5. Wave attenuation in mangroves; a quantitative approach to field observations

    NARCIS (Netherlands)

    Horstman, E.M.; Dohmen-Janssen, C.M.; Narra, P.M.F.; Berg, van den N.J.F.; Siemerink, M.; Hulscher, S.J.M.H.

    2014-01-01

    Coastal mangroves, dwelling at the interface between land and sea, provide an important contribution to reducing risk from coastal hazards by attenuating incident waves and by trapping and stabilizing sediments. This paper focusses on relations between vegetation densities, wave attenuation rates, s

  6. Doxycycline Attenuated Pulmonary Fibrosis Induced by Bleomycin in Mice

    OpenAIRE

    Fujita, Masaki; Ye, Qing; Ouchi, Hiroshi; Harada, Eiji; Inoshima, Ichiro; Kuwano, Kazuyoshi; Nakanishi, Yoichi

    2006-01-01

    The administration of doxycycline prior to bleomycin in mice attenuated pulmonary fibrosis. Bronchoalveolar neutrophil influx and gelatinase activity, but not caseinolytic activity, were attenuated by doxycycline. Established fibrosis was not affected by doxycycline. Thus, doxycycline might be useful for slowing down pulmonary fibrosis by biological activity other than antibacterial activity.

  7. Flux attenuation at NREL's High-Flux Solar Furnace

    Science.gov (United States)

    Bingham, Carl E.; Scholl, Kent L.; Lewandowski, Allan A.

    1994-10-01

    The High-Flux Solar Furnace (HFSF) at the National Renewable Energy Laboratory (NREL) has a faceted primary concentrator and a long focal-length-to-diameter ratio (due to its off-axis design). Each primary facet can be aimed individually to produce different flux distributions at the target plane. Two different types of attenuators are used depending on the flux distribution. A sliding-plate attenuator is used primarily when the facets are aimed at the same target point. The alternate attenuator resembles a venetian blind. Both attenuators are located between the concentrator and the focal point. The venetian-blind attenuator is primarily used to control the levels of sunlight failing on a target when the primary concentrators are not focused to a single point. This paper will demonstrate the problem of using the sliding-plate attenuator with a faceted concentrator when the facets are not aimed at the same target point. We will show that although the alternate attenuator necessarily blocks a certain amount of incoming sunlight, even when fully open, it provides a more even attenuation of the flux for alternate aiming strategies.

  8. X-Ray Form Factor, Attenuation and Scattering Tables

    Science.gov (United States)

    SRD 66 X-Ray Form Factor, Attenuation and Scattering Tables (Web, free access)   This database collects tables and graphs of the form factors, the photoabsorption cross section, and the total attenuation coefficient for any element (Z <= 92).

  9. The attenuation anisotropy of mudstones and shales in subsurface formations

    Institute of Scientific and Technical Information of China (English)

    SHI Ge; DENG Jixin

    2005-01-01

    We have measured the relationships in the laboratorial condition between the attenuation in three samples of mudstones and shales as well as two samples of layered sandstones and the alteration in direction, confining pressure and pore fluid. The relative contributions of different attenuation mechanisms are also discussed. Studies show that the attenuation in dry and saturated samples is strongly related to pressure and direction. The attenuation coefficient of P-wave propagating parallel to bedding (PH) is less than that of P-wave propagating vertical to bedding (PV), while the attenuation coefficient of S-wave both propagating and vibrating parallel to bedding (SH) and that of S-wave propagating vertical to bedding while vibrating parallel to bedding (SV1) are less than that of S-wave propagating parallel to bedding while vibrating vertical to bedding (SV). Under oil saturated conditions, the Biot flow attenuation acts as the dominant mechanism for waves propagating parallel to bedding, while the frame anelastic attenuation and squirt flow attenuation seem to play important roles in condition of propagation vertical to bedding.

  10. Importance of Attenuation Correction (AC) for Small Animal PET Imaging

    DEFF Research Database (Denmark)

    El Ali, Henrik H.; Bodholdt, Rasmus Poul; Jørgensen, Jesper Tranekjær;

    2012-01-01

    concentration in the same organ with and without AC revealed an overall attenuation recovery of 9–21% for MAP reconstructed images, i.e., SUV without AC could underestimate the true activity at this level. For subcutaneous tumors, the attenuation was 13 ± 4% (9–17%), for kidneys 20 ± 1% (19...

  11. A Precision Variable, Double Prism Attenuator for CO(2) Lasers.

    Science.gov (United States)

    Oseki, T; Saito, S

    1971-01-01

    A precision, double prism attenuator for CO(2) lasers, calibrated by its gap capacitance, was constructed to evaluate its possible use as a standard for attenuation measurements. It was found that the accuracy was about 0.1 dB with a dynamic range of about 40 dB.

  12. Epidermoid cyst radiologically mistaken as a left sided subpulmonic effusion.

    Science.gov (United States)

    Sameh, Ibrahim Sersar; Gewaeli, NourEldeen Noaman; Hamza, Usama Ali; Awadalla, Mohammed Mounir el-said

    2003-09-01

    A 33-year-old female had a left sided chest pain for the last 3 months. Chest X-ray showed a left basal opacity. Computed tomography chest suggested a left sided subpulmonic effusion (17.5x12.2x13 cm) with thick enhanced walls with marked collapse of the left lower lobe and displacement of the heart and mediastinum to the right side. Trial of thoracocentesis was done and it was positive. Trial of intercostal tube insertion was done with a sense of very thick pleura and the patient developed a vasovagal attack. Accordingly, exploratory thoracotomy was decided. Intraoperative assessment showed a huge anterosuperior mediastinal cyst attached to the pericardium and was successfully resected. The pathological findings were compatible with epidermoid cyst. PMID:17670071

  13. Delusional misidentifications and duplications: right brain lesions, left brain delusions.

    Science.gov (United States)

    Devinsky, Orrin

    2009-01-01

    When the delusional misidentification syndromes reduplicative paramnesia and Capgras syndromes result from neurologic disease, lesions are usually bifrontal and/or right hemispheric. The related disorders of confabulation and anosognosis share overlapping mechanisms and anatomic pathology. A dual mechanism is postulated for the delusional misidentification syndromes: negative effects from right hemisphere and frontal lobe dysfunction as well as positive effects from release (i.e., overactivity) of preserved left hemisphere areas. Negative effects of right hemisphere injury impair self-monitoring, ego boundaries, and attaching emotional valence and familiarity to stimuli. The unchecked left hemisphere unleashes a creative narrator from the monitoring of self, memory, and reality by the frontal and right hemisphere areas, leading to excessive and false explanations. Further, the left hemisphere's cognitive style of categorization, often into dual categories, leads it to invent a duplicate or impostor to resolve conflicting information. Delusions result from right hemisphere lesions. But it is the left hemisphere that is deluded.

  14. Aneurysm of the left aortic sinus causing acute myocardial infarction

    International Nuclear Information System (INIS)

    This report describes the findings and management of a young male who presented with an acute ST-segment elevation myocardial infarction due to compression of the circumflex coronary artery by a large aneurysm of left sinus of Valsalva

  15. Children left behind in romania: anxiety and predictor variables.

    Science.gov (United States)

    Tomșa, R; Jenaro, C

    2015-04-01

    Children left behind while their parents immigrate or travel for employment are becoming a widespread phenomenon for economic reasons, creating potentially stressful and inadequate developmental support for a substantial portion of some countries' working class populations. This study assessed the emotional status and coping skills of two matched samples of 163 Romanian children left behind and 163 comparable children living with their parents. The State-Trait Anxiety Inventory for Children, the Anger Expression Scale for Children, the Short Mood and Feelings Questionnaire, and the Children's Coping Strategies Checklist were utilized. Higher anxiety and depression were observed in left-behind children compared to the control group living with parents. Hierarchical multiple regression supported the relevance of coping strategies, controlled for sociodemographic characteristics, to help explain anxiety in left-behind children. Strategies to promote psychological health and general well being are discussed.

  16. Phenomenology of Left-Right Twin Higgs Model

    CERN Document Server

    Goh, H S; Goh, Hock-Seng; Su, Shufang

    2007-01-01

    Twin Higgs mechanism has recently been proposed to solve the ``little Hierarchy'' problem. We studied the implementation of twin Higgs mechanism in left-right models. We discussed the particle spectrum, and the collider phenomenology at the Large Hadron Collider.

  17. Phenomenology of Left-Right Twin Higgs Model

    OpenAIRE

    Goh, Hock-Seng; Su, Shufang

    2006-01-01

    Twin Higgs mechanism has recently been proposed to solve the ``little Hierarchy'' problem. We studied the implementation of twin Higgs mechanism in left-right models. We discussed the particle spectrum, and the collider phenomenology at the Large Hadron Collider.

  18. [Keratoacanthoma on the left cheek of Galileo Galilei].

    Science.gov (United States)

    Roth, W

    1986-09-01

    In an oil painting from the School of Sustermans, which can be seen in the Palazzo Pitti in Florence, we diagnosed the alterations typical of a keratoacanthoma in the left cheek-bone area of the portrayed Galileo Galilei.

  19. Aneurysm of the left aortic sinus causing acute myocardial infarction

    OpenAIRE

    Jan-Peter Smedema; Vernon Freeman; Johan Brink

    2011-01-01

    This report describes the findings and management of a young male who presented with an acute ST-segment elevation myocardial infarction due to compression of the circumflex coronary artery by a large aneurysm of left sinus of Valsalva.

  20. Some Tree Trimming Best Left to The Pros

    Science.gov (United States)

    ... https://medlineplus.gov/news/fullstory_159924.html Some Tree Trimming Best Left to the Pros For instance, ... July 17, 2016 (HealthDay News) -- Trimming or removing trees should be done with caution, particularly near power ...

  1. Ostial left main coronary stenosis in a frequent flyer.

    LENUS (Irish Health Repository)

    O'Sullivan, John F

    2009-05-15

    A 52 year old gentleman presented with chest pain, after a long distance flight from India; he had made long haul flights every 2 weeks over the last 5 years as part of his job. His ECG revealed T wave inversion in leads V1-3. Cardiac biomarkers including troponin were negative; we proceeded to exercise stress testing (EST). This revealed 2 mm ST depression at 2 min of the standard Bruce protocol, associated with chest pain. He was taken immediately to the coronary catheterization laboratory; engagement of the left main caused pressure damping with 6 French, then 5 French diagnostic Judkins left 4 catheters. An ostial left main stenosis was seen; the right and left coronary trees otherwise had no significant stenoses. He had normal LV function. He underwent inpatient CABG 7 days later.

  2. A Case Report of Left-Sided Headache with Rhinocleisis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Case Report A patient, with a complaint of a left-sided headache plus a rhinocleisis for a month, was admitted to our hospital. The clinical diagnosis showed that it was a primary adenoid cystic carcinoma (ACC) of the nasopharynx.

  3. Left ventricular to right atrial shunt resulting from infective endocarditis.

    Science.gov (United States)

    Ellis, C J; Gray, K E; Ainscow, D A

    1975-02-01

    A unique case is described in which infective endocarditis of the aortic valve led to intractable heart failure and necropsy examination showed that the patient had developed a communication between the left ventricle and right atrium.

  4. Phonological decisions require both the left and right supramarginal gyri

    DEFF Research Database (Denmark)

    Hartwigsen, Gesa; Baumgaertner, Annette; Price, Cathy J;

    2010-01-01

    Recent functional imaging studies demonstrated that both the left and right supramarginal gyri (SMG) are activated when healthy right-handed subjects make phonological word decisions. However, lesion studies typically report difficulties with phonological processing after left rather than right...... during phonological, semantic, and perceptual decisions. To test laterality and anatomical specificity, we compared the effect of TMS over the left, right, or bilateral SMG and angular gyri. The accuracy and reaction times of phonological decisions were selectively disrupted relative to semantic...... and perceptual decisions when real TMS was applied over the left, right, or bilateral SMG. These effects were not observed for TMS over the angular gyri. A follow-up experiment indicated that the threshold-intensity for inducing a disruptive effect on phonological decisions was identical for unilateral TMS over...

  5. Left Ventricular Function After Prolonged Exercise in Equine Endurance Athletes

    DEFF Research Database (Denmark)

    Flethøj, M.; Schwarzwald, C. C.; Haugaard, M. M.;

    2016-01-01

    Background: Prolonged exercise in human athletes is associated with transient impairment of left ventricular (LV) function, known as cardiac fatigue. Cardiac effects of prolonged exercise in horses remain unknown. Objectives :To investigate the effects of prolonged exercise on LV systolic...

  6. Characteristics of surface waves in anisotropic left-handed materials

    Institute of Scientific and Technical Information of China (English)

    Jiang Yong-Yuan; Shi Hong-Yan; Zhang Yong-Qiang; Hou Chun-Feng; Sun Xiu-Dong

    2007-01-01

    We report the coexistence of TE and TM surface modes in certain same frequency domain at the interface between one isotropic regular medium and another biaxially anistotropic left-handed medium. The conditions for the existence of TE and TM polarized surface waves in biaxially anisotropic left-handed materials are identified, respectively.The Poynting vector and the energy density associated with surface modes are calculated. Depending on the system parameters, either TE or TM surface modes can have the time averaged Poynting vector directed to or opposite to the mode phase velocity. It is seen that the characteristics of surface waves in biaxially anisotropic left-handed media are significantly different from that in isotropic left-handed media.

  7. Left-handed sperm removal by male Calopteryx damselflies (Odonata).

    Science.gov (United States)

    Tsuchiya, Kaori; Hayashi, Fumio

    2014-01-01

    Male genitalia in several insect species are asymmetry in right and left shape. However, the function of such asymmetric male genitalia is still unclear. We found that the male genitalia of the damselfly Calopteryx cornelia (Odonata: Calopterygidae) are morphologically symmetric just after emergence but asymmetric after reproductive maturation. Males remove rival sperm stored in the female bursa copulatrix (single spherical sac) and the following spermatheca (Y-shaped tubular sac) prior to their own ejaculation to prevent sperm competition. Males possess the aedeagus with a recurved head to remove bursal sperm and a pair of spiny lateral processes to remove spermathecal sperm. The right lateral process is less developed than the left, and sperm stored in the right spermathecal tube are rarely removed. Experiments involving surgical cutting of each lateral process demonstrated that only the left process functions in spermathecal sperm removal. Thus, males of C. cornelia are left-handed in their sperm removal behaviour at copulation.

  8. Broad beam and narrow beam attenuation in Lipowitz's metal.

    Science.gov (United States)

    el-Khatib, E E; Podgorsak, E B; Pla, C

    1987-01-01

    Attenuation properties of Lipowitz's metal have been studied for narrow and broad beams of cobalt-60 gamma rays and 4-10 MV x-rays. The measured transmitted fraction for geometries used in radiotherapy depends on the field size and depth of measurement. Therefore a calculation of dose for partially attenuated beams based on narrow beam attenuation coefficients can cause large errors in dosimetry. Our simple calculation of transmitted fractions based on primary attenuation and scattered radiation agrees quite well with the measured data for therapeutic geometries. Also given is a table for linear, mass attenuation, and mass energy absorption coefficients of Lipowitz's metal in the photon energy range from 10 keV to 10 MeV. PMID:3104738

  9. Modernisation and the New Left in sixties Britain

    OpenAIRE

    Goldie, Christopher Thomas

    2005-01-01

    The aim of this thesis is to explore the relationship between the New Left and modernisation, and to suggest that modernisation provides a powerful means of understanding the underlying dynamics of Britain's history in the 1960s. This relationship is understood in terms of a politics of space. The New Left is defined broadly for this purpose as a movement emerging from the dislocating experiences of social, cultural and physical mobility in the postwar period. What is termed the 'modernisatio...

  10. Regional renal venous hypertension and left-sided varicocele

    OpenAIRE

    O. B. Zhukov; A. V. Verzin; P. L. Penkov

    2013-01-01

    One of the most frequent correctable causes of male infertility is a varicocele. The etiology and pathogenesis of varicocele to date is a matter of debate. The aim of our study was to determine the causes and incidence of regional renal hypertension in patients with leftsided varicocele. The study involved 110 patients with left-sided varicocele in age from 18 to 35 years. Algorithm for evaluation of patients with left-sided varicocele included: physical examination, ultrasound with Doppler k...

  11. Left ventricular muscle mass regression after aortic valve replacement.

    OpenAIRE

    Lee, J. W.; Choi, K. J.; Lee, S G; Choo, S. J.; Kim, J.O.; Kang, D H; Song, J.K.; Song, M. G.

    1999-01-01

    Implanting a valve that will reduce left ventricular mass is critical in aortic stenosis. Regression of left ventricular hypertrophy in 46 aortic valve replacement (AVR) patients receiving a St. Jude Medical (SJM) valve was assessed by serial electrocardiographic and echocardiographic studies during the preoperative, immediate, and late postoperative periods. The patients were divided into three groups according to valve size; 19 mm group (n=9), 21 mm group (n=20), and 23+mm group (n=17). The...

  12. Reversible Pulmonary Hypertension in Adolescent with Left Atrial Myxoma

    OpenAIRE

    Kim, Byong-Kyu; Cho, Jung-Nam; Park, Hye-Jin; Hong, Seung-Pyo; Son, Ja-Yung; Lee, Jin-Bae; Ryu, Jae-Keun; Choi, Ji-Yong; Chang, Sung-Guk; Kim, Kee-Sik

    2011-01-01

    We report a patient of left atrial huge myxoma presenting with severe pulmonary hypertension in adolescents. A patient was a 14-year-old boy presented with sudden onset dyspnea. Transthoracic echocardiographic study revealed the presence of a nodular, 4.34 × 8.11 cm sized, mobile, hyperechoic mass in the left atrium and severe pulmonary hypertension with tricuspid insufficiency. After surgical therapy, tricuspid regurgitation and pulmonary hypertension was decreased and the patient was stabil...

  13. Comparative response of right and left ventricles to volume overload.

    Science.gov (United States)

    Mathew, R; Thilenius, O G; Arcilla, R A

    1976-08-01

    The cardiac volume data of 49 normal children were compared with those of 23 with secundum atrial septal defect and 24 with patent ductus arteriosus. Significantly smaller ventricular end-diastolic volumes were observed in the normal infants than in older children (right ventricle 53.9 versus 75.5 cm3/m2; left ventricle 46.7 versus 63.6 cm3/m2). "Distensibility" of the right ventricle (DRV), left ventricle (DLV) and left atrium increased normally with age. DRV and DLV were similar shortly after birth; thereafter, DRV increased more rapidly than DLV (mean DRV 12.7; mean DLV 7.8 cm3/m2 per mm Hg, P less than 0.001). In both atrial septal defect and patent ductus arteriosus, the ipsilateral (involved) ventricles had increased volume, increased output, normal ejection fraction and increased distensibility. The contralateral (left) ventricle in atrial septal defect was smaller than normal (39.6 versus 49.7 cm3, P less than 0.001), and had a smaller ejection fraction (0.63 versus 0.71, P less than 0.01) and output (3.70 versus 4.57 liters/min per m2, P less than 0.005). In contrast, the contralateral (right) ventricle in patent ductus arteriosus remained normal. Left atrial maximal volume was larger than normal in atrial septal defect (46.6 versus 35.9 cm3/m2, P less than 0.001). The left atrial and left ventricular volumes in patent ductus arteriosus were, respectively, 152 and 142 percent of normal, indicating comparable response to the volume load. The left head changes in atrial septal defect may be related both to a functionally restrictive defect and to the difference in distensibility of the ventricles.

  14. Diverticulum of the midthoracic oesophagus and left diaphragmatic relaxation

    OpenAIRE

    Antonacci, Nicola; Sciannamea, Gianluca; Antonacci, Filippo; Casadei, Riccardo; Ricci, Claudio; Di Saverio, Salomone; Minni, Francesco

    2010-01-01

    The case of a 58-year-old man with a large midthoracic oesophageal diverticulum and a left diaphragmatic relaxation who presented with night regurgitations, abdominal bloating, epigastric burning and a sensation of fullness after meals is reported. The patient underwent a successful thoracotomic diverticulectomy with left diaphragmatic plicature. The postoperative course was uneventful. To our knowledge this is the first reported case of an association between midthoracic oesophageal divertic...

  15. Developmental dyslexia: dysfunction of a left hemisphere reading network

    Directory of Open Access Journals (Sweden)

    Fabio eRichlan

    2012-05-01

    Full Text Available This mini-review summarizes and integrates findings from recent meta-analyses and original neuroimaging studies on functional brain abnormalities in dyslexic readers. Surprisingly, there is little empirical support for the standard neuroanatomical model of developmental dyslexia, which localizes the primary phonological decoding deficit in left temporo-parietal regions. Rather, recent evidence points to a dysfunction of a left hemisphere reading network, which includes occipito-temporal, inferior frontal, and inferior parietal regions.

  16. The role of left perisylvian cortical regions in spelling ☆

    OpenAIRE

    Henry, Maya L.; Beeson, Pélagie M.; Stark, Amy J.; Rapcsak, Steven Z.

    2006-01-01

    In order to examine the role of left perisylvian cortex in spelling, 13 individuals with lesions in this area were administered a comprehensive spelling battery. Their spelling of regular words, irregular words, and nonwords was compared with that of individuals with extrasylvian damage involving left inferior temporo–occipital cortex and normal controls. Perisylvian patients demonstrated a lexicality effect, with nonwords spelled worse than real words. This pattern contrasts with the deficit...

  17. Left Atrium Papillary Fibroelastomas: A Cause of Cerebral Emboli

    Directory of Open Access Journals (Sweden)

    A. G. Ciss

    2012-01-01

    Full Text Available Papillary fibroelastomas are cardiac benign tumours. Among the benign cardiac tumor, papillary fibroelastomas are reported second after myxomas. Most often diagnosed incidentally, papillary fibroelastomas may embolize to cerebral circulation. Valvular locations are predominant; location in left atrium is rare. In this paper, we present a case of papillary fibroelastoma located in left atrium with symptoms of cerebral embolization. Transoesophageal echocardiography diagnosed a mobile mass. The patient was treated with surgical resection without further embolic complication.

  18. My Left Foot——The Lettet “A”

    Institute of Scientific and Technical Information of China (English)

    ChristyBrown; 许洪武

    2004-01-01

    Christy Brown, the celebrated painter and writer,overcame the difficulties of being born with cerebral palsy by using his left foot,the only part of his body which he could use with real control.In this story you will be comparing the opening of Christy's autobiographical novel with a scene from the successful film of his early life, “My Left Foot”.

  19. Left ventricular thrombus associated with arteriovenous extra corporeal membrane oxygenation

    OpenAIRE

    Makdisi, George; Hashmi, Zubair A; Wozniak, Thomas C.; Wang, I-Wen

    2015-01-01

    Extra corporeal membrane oxygenation (ECMO) has remarkably progressed over the recent years. It has become an invaluable tool in the care of adults and pediatric patients with severe cardiogenic shock. At the initiation of ECMO support, the left ventricular contractility is profoundly impaired. Inadequate right ventricular drainage and bronchial circulation can lead to left ventricular distension, with potential deleterious consequences, ranging from inadequate myocardial rest, pulmonary edem...

  20. Electrocardiographic Criteria for Left Ventricular Hypertrophy in Children

    OpenAIRE

    Rijnbeek, Peter R; van Herpen, Gerard; Kapusta, Livia; ten Harkel, A. Derk Jan; Witsenburg, Maarten; Kors, Jan A.

    2008-01-01

    Previous studies to determine the sensitivity of the electrocardiogram (ECG) for left ventricular hypertrophy (LVH) in children had their imperfections: they were not done on an unselected hospital population, several criteria used in adults were not applied to children, and obsolete limits of normal for the ECG parameters were used. Furthermore, left ventricular mass (LVM) was taken as the reference standard for LVH, with no regard for other clinical evidence. The study population consisted ...

  1. Unusual distribution of noncompaction of left ventricular myocardium.

    Science.gov (United States)

    Bhardwaj, Ravindra; Abro, Masroor; Gharib, Wissam; Warden, Bradford E; Jain, Abnash; Failinger, Conard F

    2015-01-01

    This case report highlights a rare case of isolated septal noncompaction of the left ventricle, a congenital condition, in a previously asymptomatic adult patient who presented with syncope. Management of left ventricular noncompaction (LVNC) includes treatment for heart failure, arrhythmias, and thromboembolic events; but no criteria exist for primary prophylaxis in patients that might be at high risk. To our knowledge this is the first report of isolated septal noncompaction in a previously asymptomatic adult patient. PMID:25665274

  2. CD28/B7 Deficiency Attenuates Systolic Overload-Induced Congestive Heart Failure, Myocardial and Pulmonary Inflammation, and Activated T Cell Accumulation in the Heart and Lungs.

    Science.gov (United States)

    Wang, Huan; Kwak, Dongmin; Fassett, John; Hou, Lei; Xu, Xin; Burbach, Brandon J; Thenappan, Thenappan; Xu, Yawei; Ge, Jun-Bo; Shimizu, Yoji; Bache, Robert J; Chen, Yingjie

    2016-09-01

    The inflammatory response regulates congestive heart failure (CHF) development. T cell activation plays an important role in tissue inflammation. We postulate that CD28 or B7 deficiency inhibits T cell activation and attenuates CHF development by reducing systemic, cardiac, and pulmonary inflammation. We demonstrated that chronic pressure overload-induced end-stage CHF in mice is characterized by profound accumulation of activated effector T cells (CD3(+)CD44(high) cells) in the lungs and a mild but significant increase of these cells in the heart. In knockout mice lacking either CD28 or B7, there was a dramatic reduction in the accumulation of activated effector T cells in both hearts and lungs of mice under control conditions and after transverse aortic constriction. CD28 or B7 knockout significantly attenuated transverse aortic constriction-induced CHF development, as indicated by less increase of heart and lung weight and less reduction of left ventricle contractility. CD28 or B7 knockout also significantly reduced transverse aortic constriction-induced CD45(+) leukocyte, T cell, and macrophage infiltration in hearts and lungs, lowered proinflammatory cytokine expression (such as tumor necrosis factor-α and interleukin-1β) in lungs. Furthermore, CD28/B7 blockade by CTLA4-Ig treatment (250 μg/mouse every 3 days) attenuated transverse aortic constriction-induced T cell activation, left ventricle hypertrophy, and left ventricle dysfunction. Our data indicate that CD28/B7 deficiency inhibits activated effector T cell accumulation, reduces myocardial and pulmonary inflammation, and attenuates the development of CHF. Our findings suggest that strategies targeting T cell activation may be useful in treating CHF.

  3. Pre-existing interleukin 10 in cerebral arteries attenuates subsequent brain injury caused by ischemia/reperfusion.

    Science.gov (United States)

    Liang, Qiu-Juan; Jiang, Mei; Wang, Xin-Hong; Le, Li-Li; Xiang, Meng; Sun, Ning; Meng, Dan; Chen, Si-Feng

    2015-09-01

    Recurrent stroke is difficult to treat and life threatening. Transfer of anti-inflammatory gene is a potential gene therapy strategy for ischemic stroke. Using recombinant adeno-associated viral vector 1 (rAAV1)-mediated interleukin 10 (IL-10), we investigated whether transfer of beneficial gene into the rat cerebral vessels during interventional treatment for initial stroke could attenuate brain injury caused by recurrent stroke. Male Wistar rats were administered rAAV1-IL-10, rAAV1-YFP, or saline into the left cerebral artery. Three weeks after gene transfer, rats were subjected to occlusion of the left middle cerebral artery (MCAO) for 45 min followed by reperfusion for 24 h. IL-10 levels in serum were significantly elevated 3 weeks after rAAV1-IL-10 injection, and virus in the cerebral vessels was confirmed by in situ hybridization. Pre-existing IL-10 but not YFP decreased the neurological dysfunction scores, brain infarction volume, and the number of injured neuronal cells. AAV1-IL-10 transduction increased heme oxygenase (HO-1) mRNA and protein levels in the infarct boundary zone of the brain. Thus, transduction of the IL-10 gene in the cerebral artery prior to ischemia attenuates brain injury caused by ischemia/reperfusion in rats. This preventive approach for recurrent stroke can be achieved during interventional treatment for initial stroke.

  4. Silent myocardial ischemia evaluated by ambulatory left ventricular function monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Imai, Kamon; Yumikura, Sei; Araki, Yasushi; Ando, Tatsuo; Saito, Satoshi; Ozawa, Yukio; Hatano, Michinobu; Kamata, Rikisaburo (Nihon Univ., Tokyo (Japan). School of Medicine)

    1989-12-01

    To determine whether left ventricular function is less disturbed in asymptomatic ischemia than in symptomatic ischemia, exercise-induced left ventricular function was measured in beat-to-beat using an ambulatory left ventricular function monitoring system. The study subjects were 22 patients with coronary artery disease. Supine and sitting ergometer exercise tests were performed. Of 44 exercise tests, 33 showed significant ST depression on electro-cardiograms. Among these 33, 17 were asymptomatic: 16, symptomatic. The left ventricular functions during exercise of these 33 were analyzed and compared with those of five normal controls. The changes in end-diastolic volume were not so significant either in controls or in the asymptomatic and symptomatic groups, but the changes in end-systolic volume were reversed in the diseased group, particularly in the symptomatic group. The changes in ejection fraction (EF), therefore, were significantly negative in the diseased group, particularly in the symptomatic group. The correlation between exercise-induced left ventricular dysfunction and symptoms was evaluated among the 33 patients. Symptoms were present in 35% (6/17) in <10% decrease in EF, 44% (4/9) in 10{approx}15% decrease, and 85% (6/7)in {ge}15% decrease, respectively. Thus, asymptomatic ischemia represents a lesser degree of myocardial ischemia as indicated by mild left ventricular dysfunction, compared with symptomatic ischemia. However, some cases of severe myocardial ischemia did not develop symptoms. We concluded that silent myocardial ischemia is responsible for a lesser degree of myocardial ischemia and decreased pain perception. (author).

  5. Left versus right deceased donor renal allograft outcome.

    LENUS (Irish Health Repository)

    Phelan, Paul J

    2009-12-01

    It has been suggested that the left kidney is easier to transplant than the right kidney because of the longer length of the left renal vein, facilitating the formation of the venous anastomosis. There are conflicting reports of differing renal allograft outcomes based on the side of donor kidney transplanted (left or right).We sought to determine the effect of side of donor kidney on early and late allograft outcome in our renal transplant population. We performed a retrospective analysis of transplanted left-right deceased donor kidney pairs in Ireland between January 1, 1998 and December 31, 2008. We used a time to death-censored graft failure approach for long-term allograft survival and also examined serum creatinine at different time points post-transplantation. All outcomes were included from day of transplant onwards. A total of 646 transplants were performed from 323 donors. The incidence of delayed graft function was 16.1% in both groups and there was no significant difference in acute rejection episodes or serum creatinine from 1 month to 8 years post-transplantation.There were 47 death-censored allograft failures in the left-sided group compared to 57 in the right-sided group (P = 0.24). These observations show no difference in renal transplant outcome between the recipients of left- and right-sided deceased donor kidneys.

  6. MYOCARDIAL DEFORMATION AND COMPLETE LEFT BUNDLE BRANCH BLOCK

    Directory of Open Access Journals (Sweden)

    E. N. Pavlyukova

    2015-12-01

    Full Text Available Tissue Doppler imaging is evolving as a useful echocardiographic tool for quantitative assessment of left ventricular systolic and diastolic function. Over the last 10 years, myocardial deformation imaging has become possible initially with tissue Doppler , and more recently with myocardial speckle-tracking using 2D echocardiography. Unlike simple tissue velocity measurements, deformation measurements are specific for the region of interest. Strain rate or strain measurements have been used as sensitive indicators for subclinical diseases, and it is the most widely used tool to assess mechanical dyssynchrony. Left bundle branch block is a frequent, etiologically heterogeneous, clinically hostile and diagnostically challenging entity. About 2% of patients underwent cardiac stress testing show stable or intermittent left bundle branch block. Presence of left bundle branch block is associated with a lower and slower diastolic coronary flow velocity especially during hyperemia. Stress echocardiography is the best option for the diagnosis of ischemic heart disease, albeit specificity and sensitivity reduce in patients with left bundle branch block in the territory of left anterior descending artery in presence of initial septum dyskinesia.

  7. Determination of mass attenuation coefficient in wood and leaves of typical trees by gamma-ray attenuation technique

    International Nuclear Information System (INIS)

    Using an 241 Am source the mass attenuation coefficient of different woods and leaves of typical species of the Atlantic Forest were measured. The results for natural wood, dry wood and dry leaves indicate that the variation is very small among different species. However, woods present a higher attenuation than leaves, both depending on their water content. (author). 10 refs., 3 figs., 1 tab

  8. Impact of Atrial Fibrillation Ablation on Left Ventricular Filling Pressure and Left Atrial Remodeling

    International Nuclear Information System (INIS)

    Left ventricular (LV) diastolic dysfunction is associated with new-onset atrial fibrillation (AF), and the estimation of elevated LV filling pressures by E/e' ratio is related to worse outcomes in patients with AF. However, it is unknown if restoring sinus rhythm reverses this process. To evaluate the impact of AF ablation on estimated LV filling pressure. A total of 141 patients underwent radiofrequency (RF) ablation to treat drug-refractory AF. Transthoracic echocardiography was performed 30 days before and 12 months after ablation. LV functional parameters, left atrial volume index (LAVind), and transmitral pulsed and mitral annulus tissue Doppler (e' and E/e') were assessed. Paroxysmal AF was present in 18 patients, persistent AF was present in 102 patients, and long-standing persistent AF in 21 patients. Follow-up included electrocardiographic examination and 24-h Holter monitoring at 3, 6, and 12 months after ablation. One hundred seventeen patients (82.9%) were free of AF during the follow-up (average, 18 ± 5 months). LAVind reduced in the successful group (30.2 mL/m2 ± 10.6 mL/m2 to 22.6 mL/m2 ± 1.1 mL/m2, p < 0.001) compared to the non-successful group (37.7 mL/m2 ± 14.3 mL/m2 to 37.5 mL/m2 ± 14.5 mL/m2, p = ns). Improvement of LV filling pressure assessed by a reduction in the E/e' ratio was observed only after successful ablation (11.5 ± 4.5 vs. 7.1 ± 3.7, p < 0.001) but not in patients with recurrent AF (12.7 ± 4.4 vs. 12 ± 3.3, p = ns). The success rate was lower in the long-standing persistent AF patient group (57% vs. 87%, p = 0.001). Successful AF ablation is associated with LA reverse remodeling and an improvement in LV filling pressure

  9. Impact of Atrial Fibrillation Ablation on Left Ventricular Filling Pressure and Left Atrial Remodeling

    Directory of Open Access Journals (Sweden)

    Simone Nascimento dos Santos

    2014-12-01

    Full Text Available Background: Left ventricular (LV diastolic dysfunction is associated with new-onset atrial fibrillation (AF, and the estimation of elevated LV filling pressures by E/e' ratio is related to worse outcomes in patients with AF. However, it is unknown if restoring sinus rhythm reverses this process. Objective: To evaluate the impact of AF ablation on estimated LV filling pressure. Methods: A total of 141 patients underwent radiofrequency (RF ablation to treat drug-refractory AF. Transthoracic echocardiography was performed 30 days before and 12 months after ablation. LV functional parameters, left atrial volume index (LAVind, and transmitral pulsed and mitral annulus tissue Doppler (e' and E/e' were assessed. Paroxysmal AF was present in 18 patients, persistent AF was present in 102 patients, and long-standing persistent AF in 21 patients. Follow-up included electrocardiographic examination and 24-h Holter monitoring at 3, 6, and 12 months after ablation. Results: One hundred seventeen patients (82.9% were free of AF during the follow-up (average, 18 ± 5 months. LAVind reduced in the successful group (30.2 mL/m2 ± 10.6 mL/m2 to 22.6 mL/m2 ± 1.1 mL/m2, p < 0.001 compared to the non-successful group (37.7 mL/m2 ± 14.3 mL/m2 to 37.5 mL/m2 ± 14.5 mL/m2, p = ns. Improvement of LV filling pressure assessed by a reduction in the E/e' ratio was observed only after successful ablation (11.5 ± 4.5 vs. 7.1 ± 3.7, p < 0.001 but not in patients with recurrent AF (12.7 ± 4.4 vs. 12 ± 3.3, p = ns. The success rate was lower in the long-standing persistent AF patient group (57% vs. 87%, p = 0.001. Conclusion: Successful AF ablation is associated with LA reverse remodeling and an improvement in LV filling pressure.

  10. Impact of Atrial Fibrillation Ablation on Left Ventricular Filling Pressure and Left Atrial Remodeling

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Simone Nascimento dos, E-mail: simonens@cardiol.br [Instituto Brasília de Arritmia- Universidade de Brasília, DF (Brazil); Faculdade de Medicina (UnB), Brasília, DF (Brazil); Henz, Benhur Davi; Zanatta, André Rodrigues; Barreto, José Roberto; Loureiro, Kelly Bianca; Novakoski, Clarissa; Santos, Marcus Vinícius Nascimento dos; Giuseppin, Fabio F.; Oliveira, Edna Maria; Leite, Luiz Roberto [Instituto Brasília de Arritmia- Universidade de Brasília, DF (Brazil)

    2014-12-15

    Left ventricular (LV) diastolic dysfunction is associated with new-onset atrial fibrillation (AF), and the estimation of elevated LV filling pressures by E/e' ratio is related to worse outcomes in patients with AF. However, it is unknown if restoring sinus rhythm reverses this process. To evaluate the impact of AF ablation on estimated LV filling pressure. A total of 141 patients underwent radiofrequency (RF) ablation to treat drug-refractory AF. Transthoracic echocardiography was performed 30 days before and 12 months after ablation. LV functional parameters, left atrial volume index (LAVind), and transmitral pulsed and mitral annulus tissue Doppler (e' and E/e') were assessed. Paroxysmal AF was present in 18 patients, persistent AF was present in 102 patients, and long-standing persistent AF in 21 patients. Follow-up included electrocardiographic examination and 24-h Holter monitoring at 3, 6, and 12 months after ablation. One hundred seventeen patients (82.9%) were free of AF during the follow-up (average, 18 ± 5 months). LAVind reduced in the successful group (30.2 mL/m{sup 2} ± 10.6 mL/m{sup 2} to 22.6 mL/m{sup 2} ± 1.1 mL/m{sup 2}, p < 0.001) compared to the non-successful group (37.7 mL/m{sup 2} ± 14.3 mL/m{sup 2} to 37.5 mL/m{sup 2} ± 14.5 mL/m{sup 2}, p = ns). Improvement of LV filling pressure assessed by a reduction in the E/e' ratio was observed only after successful ablation (11.5 ± 4.5 vs. 7.1 ± 3.7, p < 0.001) but not in patients with recurrent AF (12.7 ± 4.4 vs. 12 ± 3.3, p = ns). The success rate was lower in the long-standing persistent AF patient group (57% vs. 87%, p = 0.001). Successful AF ablation is associated with LA reverse remodeling and an improvement in LV filling pressure.

  11. Photochemical Attenuation of Pesticides in Prairie Potholes

    Science.gov (United States)

    Zeng, T.; Arnold, W. A.

    2013-12-01

    Prairie potholes are small, shallow, glacially-derived wetlands scattered across a vast region extending from Midwestern United States into south central Canada known as the Prairie Pothole Region (PPR). They constitute one of the largest inland wetland systems on Earth and play a prominent role in sustaining the regional biodiversity and productivity. Throughout the PPR, historic and contemporary conversion of native prairie for agriculture resulted in a pronounced loss of potholes. Remaining potholes have become interspersed within a matrix of agricultural landscape and trap nonpoint source pollutants such as pesticides from adjacent farmland, which has raised concerns regarding negative impacts on the water quality of downstream water bodies. The fate and persistence of pesticides in potholes, however, remains largely unexplored. Prairie potholes are typically characterized by shallow depth (i.e., large photic zone) and high levels of dissolved organic matter (DOM), making them ideal for photochemical reactions. In this context, we collected pothole water samples from North Dakota to investigate the rates and mechanisms of sunlight-induced attenuation of pesticides. The photodegradation kinetics and pathways of sixteen pesticides in the pothole water were monitored under both simulated and natural sunlight. For most pesticides, photolysis accelerated in the pothole water relative to the buffer control, which pointed to the importance of photosensitized processes (i.e., indirect photolysis). Upon solar irradiation, a mixture of photochemically produced reactive intermediates (PPRIs), such as carbonate radical, hydroxyl radical, singlet oxygen, and triplet-excited state DOM, formed in the pothole water. The major pathways through which pesticides degraded were inferred from the relative contribution attributable to specific PPRIs via quencher experiments. Different classes of pesticides exhibited contrasting photochemical behavior, but singlet oxygen and triplet

  12. Ataxia telangiectasia-mutated kinase deficiency exacerbates left ventricular dysfunction and remodeling late after myocardial infarction.

    Science.gov (United States)

    Daniel, Laura L; Scofield, Stephanie L C; Thrasher, Patsy; Dalal, Suman; Daniels, Christopher R; Foster, Cerrone R; Singh, Mahipal; Singh, Krishna

    2016-08-01

    Ataxia telangiectasia-mutated kinase (ATM), a cell cycle checkpoint protein, is activated in response to DNA damage and oxidative stress. We have previously shown that ATM deficiency is associated with increased apoptosis and fibrosis and attenuation of cardiac dysfunction early (1-7 days) following myocardial infarction (MI). Here, we tested the hypothesis that enhanced fibrosis and apoptosis, as observed early post-MI during ATM deficiency, exacerbate cardiac dysfunction and remodeling in ATM-deficient mice late post-MI. MIs were induced in wild-type (WT) and ATM heterozygous knockout (hKO) mice by ligation of the left anterior descending artery. Left ventricular (LV) structural and functional parameters were assessed by echocardiography 14 and 28 days post-MI, whereas biochemical parameters were measured 28 days post-MI. hKO-MI mice exhibited exacerbated LV dysfunction as observed by increased LV end-systolic volume and decreased percent fractional shortening and ejection fraction. Infarct size and thickness were not different between the two genotypes. Myocyte cross-sectional area was greater in hKO-MI group. The hKO-MI group exhibited increased fibrosis in the noninfarct and higher expression of α-smooth muscle actin (myofibroblast marker) in the infarct region. Apoptosis and activation of GSK-3β (proapoptotic kinase) were significantly lower in the infarct region of hKO-MI group. Matrix metalloproteinase 2 (MMP-2) expression was not different between the two genotypes. However, MMP-9 expression was significantly lower in the noninfarct region of hKO-MI group. Thus ATM deficiency exacerbates cardiac remodeling late post-MI with effects on cardiac function, fibrosis, apoptosis, and myocyte hypertrophy. PMID:27288435

  13. The left atrium, atrial fibrillation, and the risk of stroke in hypertensive patients with left ventricular hypertrophy

    DEFF Research Database (Denmark)

    Wachtell, K.; Devereux, R.B.; Lyle, P.A.;

    2008-01-01

    The Losartan Intervention For Endpoint reduction in hypertension (LIFE) study provided extensive data on predisposing factors, consequences, and prevention of atrial fibrillation (AF) in patients with hypertension and left ventricular (LV) hypertrophy. Randomized losartan-based treatment...

  14. Association of Left Atrial Volume With Mortality Among ESRD Patients With Left Ventricular Hypertrophy Referred for Kidney Transplantation

    OpenAIRE

    Patel, Rajan K.; Jardine, Alan G.M.; Patrick B. Mark; Cunningham, Anthony F.; Steedman, Tracey; Powell, Joanna R.; McQuarrie, Emily P.; Stevens, Kathryn K; Dargie, Henry J; Jardine, Alan G

    2010-01-01

    Background Left ventricular hypertrophy (LVH) is common in patients with end-stage renal disease (ESRD) and an independent risk factor for premature cardiovascular death. Left atrial volume (LAV), measured using echocardiography, predicts death in patients with ESRD. Cardiovascular magnetic resonance (CMR) imaging is a volume-independent method of accurately assessing cardiac structure and function in patients with ESRD. Study Design Single-center prospective observational study to assess the...

  15. 'Left behind' but not left alone: parental migration & the psychosocial health of children in Moldova.

    Science.gov (United States)

    Vanore, Michaella; Mazzucato, Valentina; Siegel, Melissa

    2015-05-01

    In Moldova, large-scale and rapidly feminised migration flows have inspired a wave of qualitative reports on children "left behind". Despite this recent interest, few studies have empirically evaluated the effects of parental migration on the psychosocial health of such children. Using data collected from a nationally-representative household survey conducted in Moldova between September 2011 and February 2012, this paper analyses the psychosocial health outcomes of children of migrant parents by comparing them with children without migrant parents (n = 1979). Child psychosocial health is measured through caregiver-reported Strengths and Difficulties Questionnaire (SDQ) scores. Multivariate regression analyses show that parental migration seldom corresponds to worse emotional symptoms outcomes but does correspond to increased conduct problems. Separate analyses for male and female children show significant gendered differences. The results partially contest the negative results that have been the subject of qualitative reports and, in particular, demonstrate that the migration of mothers infrequently results in worse psychosocial outcomes for children-contrary to what has been assumed in the discourse about parental migration in Moldova.

  16. Left ventricular systolic response to exercise in patients with systemic hypertension without left ventricular hypertrophy.

    Science.gov (United States)

    Christian, T F; Zinsmeister, A R; Miller, T D; Clements, I P; Gibbons, R J

    1990-05-15

    Supine exercise radionuclide angiography was performed in 367 men to assess left ventricular (LV) systolic response to exercise; 58 had systemic hypertension without LV hypertrophy on a resting electrocardiogram and 309 were normotensive. All patients met the following criteria defining a low pretest likelihood of coronary artery disease: age less than 50 years; normal electrocardiographic response to exercise; absence of typical or atypical chest pain; and exercise heart rate greater than 120 beats/min. Patients taking beta-receptor blockers were excluded. There were no significant differences between hypertensive and normotensive groups in peak exercise heart rate, workload or exercise duration. However, hypertensive patients had significantly higher peak exercise systolic blood pressures and peak exercise rate-pressure products. There were no differences between patients with and without hypertension in resting ejection fraction, peak exercise ejection fraction (hypertensive patients 0.71 +/- 0.01, normotensive patients 0.70 +/- 0.05) or change in ejection fraction at peak exercise (hypertensive patients 0.07 +/- 0.01, normotensive patients 0.07 +/- 0.04). Diastolic and systolic ventricular volumes tended to be smaller in the hypertensive patients, but the difference was not statistically significant. The change in systolic volume with exercise was similar in the 2 groups (hypertensive -10 +/- 3 ml/m2, normotensive -10 +/- 1 ml/m2). In the absence of electrocardiographic evidence of LV hypertrophy, systemic hypertension does not influence LV systolic response to exercise. PMID:2140008

  17. Silibinin attenuates allergic airway inflammation in mice

    International Nuclear Information System (INIS)

    Highlights: ► Silibinin diminishes ovalbumin-induced inflammatory reactions in the mouse lung. ► Silibinin reduces the levels of various cytokines into the lung of allergic mice. ► Silibinin prevents the development of airway hyperresponsiveness in allergic mice. ► Silibinin suppresses NF-κB transcriptional activity. -- Abstract: Allergic asthma is a chronic inflammatory disease regulated by coordination of T-helper2 (Th2) type cytokines and inflammatory signal molecules. Silibinin is one of the main flavonoids produced by milk thistle, which is reported to inhibit the inflammatory response by suppressing the nuclear factor-kappa B (NF-κB) pathway. Because NF-κB activation plays a pivotal role in the pathogenesis of allergic inflammation, we have investigated the effect of silibinin on a mouse ovalbumin (OVA)-induced asthma model. Airway hyperresponsiveness, cytokines levels, and eosinophilic infiltration were analyzed in bronchoalveolar lavage fluid and lung tissue. Pretreatment of silibinin significantly inhibited airway inflammatory cell recruitment and peribronchiolar inflammation and reduced the production of various cytokines in bronchoalveolar fluid. In addition, silibinin prevented the development of airway hyperresponsiveness and attenuated the OVA challenge-induced NF-κB activation. These findings indicate that silibinin protects against OVA-induced airway inflammation, at least in part via downregulation of NF-κB activity. Our data support the utility of silibinin as a potential medicine for the treatment of asthma.

  18. Ultrasonic attenuation in rare-earth monoarsenides

    Indian Academy of Sciences (India)

    BHALLA VYOMA; SINGH DEVRAJ; JAIN S K; KUMAR RAJ

    2016-06-01

    The present paper deals with the theoretical calculation of mechanical and thermophysical properties of rare-earth monoarsenides, XAs (X: Np, Pu, Th and U) using elastic constants as the input parameters. These second- and third-order elastic constants (SOECs and TOECs) are determinedin the temperature range 100–500K using Coulomb and Born–Mayer potential upto second nearest neighbours. In order to provide the link between mechanical and dynamical behaviour of crystals, parameters such as Young’s modulus, bulk modulus, Poisson’s ratio etc. are also calculated.In addition, the Cauchy relationship is obeyed by the chosen monoarsenides and are fairly anisotropic, which results in the measurement of longitudinal and shear wave velocities along $\\langle100 \\rangle$, $\\langle110\\rangle$ and $\\langle 111\\rangle$ directions. The toughness/fracture $(G/BT)$ ratio is greater than 0.60, which implies that XAs compounds are brittle at room temperature. Further, the Debye temperature is computed using Debye average velocity as the input parameter. It helps in the characterization of lattice vibrations of a solid. In this work, ultrasonic attenuation due to phonon–phonon interaction$\\alpha/f^2_{\\rm p−p}$ and thermoelastic loss $\\alpha/f ^{2}$th are computed for XAs from 100 to 500K using Mason’s theory. It further helps in evaluating the microstructural properties of the chosen materials. The obtained results indicate that XAs is mechanically stable and are compared with data availablein the literature.

  19. A prototype piecewise-linear dynamic attenuator

    Science.gov (United States)

    Hsieh, Scott S.; Peng, Mark V.; May, Christopher A.; Shunhavanich, Picha; Fleischmann, Dominik; Pelc, Norbert J.

    2016-07-01

    The piecewise-linear dynamic attenuator has been proposed as a mechanism in CT scanning for personalizing the x-ray illumination on a patient- and application-specific basis. Previous simulations have shown benefits in image quality, scatter, and dose objectives. We report on the first prototype implementation. This prototype is reduced in scale and speed and is integrated into a tabletop CT system with a smaller field of view (25 cm) and longer scan time (42 s) compared to a clinical system. Stainless steel wedges were machined and affixed to linear actuators, which were in turn held secure by a frame built using rapid prototyping technologies. The actuators were computer-controlled, with characteristic noise of about 100 microns. Simulations suggest that in a clinical setting, the impact of actuator noise could lead to artifacts of only 1 HU. Ring artifacts were minimized by careful design of the wedges. A water beam hardening correction was applied and the scan was collimated to reduce scatter. We scanned a 16 cm water cylinder phantom as well as an anthropomorphic pediatric phantom. The artifacts present in reconstructed images are comparable to artifacts normally seen with this tabletop system. Compared to a flat-field reference scan, increased detectability at reduced dose is shown and streaking is reduced. Artifacts are modest in our images and further refinement is possible. Issues of mechanical speed and stability in the challenging clinical CT environment will be addressed in a future design.

  20. Silibinin attenuates allergic airway inflammation in mice

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yun Ho [Department of Anatomy, Medical School, Institute for Medical Sciences, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of); Jin, Guang Yu [Department of Radiology, Yanbian University Hospital, YanJi 133002 (China); Guo, Hui Shu [Centralab, The First Affiliated Hospital of Dalian Medical University, Dalian 116011 (China); Piao, Hong Mei [Department of Respiratory Medicine, Yanbian University Hospital, YanJi 133000 (China); Li, Liang chang; Li, Guang Zhao [Department of Anatomy and Histology and Embryology, Yanbian University School of Basic Medical Sciences, 977 Gongyuan Road, YanJi 133002, Jilin (China); Lin, Zhen Hua [Department of Pathology, Yanbian University School of Basic Medical Sciences, YanJi 133000 (China); Yan, Guang Hai, E-mail: ghyan@ybu.edu.cn [Department of Anatomy and Histology and Embryology, Yanbian University School of Basic Medical Sciences, 977 Gongyuan Road, YanJi 133002, Jilin (China)

    2012-10-26

    Highlights: Black-Right-Pointing-Pointer Silibinin diminishes ovalbumin-induced inflammatory reactions in the mouse lung. Black-Right-Pointing-Pointer Silibinin reduces the levels of various cytokines into the lung of allergic mice. Black-Right-Pointing-Pointer Silibinin prevents the development of airway hyperresponsiveness in allergic mice. Black-Right-Pointing-Pointer Silibinin suppresses NF-{kappa}B transcriptional activity. -- Abstract: Allergic asthma is a chronic inflammatory disease regulated by coordination of T-helper2 (Th2) type cytokines and inflammatory signal molecules. Silibinin is one of the main flavonoids produced by milk thistle, which is reported to inhibit the inflammatory response by suppressing the nuclear factor-kappa B (NF-{kappa}B) pathway. Because NF-{kappa}B activation plays a pivotal role in the pathogenesis of allergic inflammation, we have investigated the effect of silibinin on a mouse ovalbumin (OVA)-induced asthma model. Airway hyperresponsiveness, cytokines levels, and eosinophilic infiltration were analyzed in bronchoalveolar lavage fluid and lung tissue. Pretreatment of silibinin significantly inhibited airway inflammatory cell recruitment and peribronchiolar inflammation and reduced the production of various cytokines in bronchoalveolar fluid. In addition, silibinin prevented the development of airway hyperresponsiveness and attenuated the OVA challenge-induced NF-{kappa}B activation. These findings indicate that silibinin protects against OVA-induced airway inflammation, at least in part via downregulation of NF-{kappa}B activity. Our data support the utility of silibinin as a potential medicine for the treatment of asthma.

  1. Atorvastatin attenuates oxidative stress in Alzheimer's disease

    Institute of Scientific and Technical Information of China (English)

    Cai Zhiyou; Yan Yong; Wang Yonglong

    2008-01-01

    Objective: To investigate serum level of SOD, MDA, ox-LDL, AchE and Ach in AD, to study atorvastatin influence on serum level of SOD, MDA, ox-LDL, AchE and Acb in AD and its neuroprotection mechanisms. Methods Subjects were divided into: normal blood lipid level group with Alzheimer's disease (A), higher blood lipid level group with Alzheimer's disease (AH), normal blood lipid level Alzheimer's disease group with atorvastatin treeatment (AT),higher blood lipid level Alzheimer's disease group with atorvastatin treeatment(AHT). Ox-LDL was measured by enzyme linked immunosorbent assay; SOD, MDA, ox-LDL, AchE, Ach and blood lipid level in AD was measured by biochemistry. Results: The serum level of MDA, AchE in AH group after atorvastatin treatment is lower ;The serum level of SOD, Ach in AH group is more increased than that of in A group; The serum level of ox-LDL in AH, A groups is lower than that of in A group; The dementia degree is lower after atorvastatin treatment. Conclusion: Atorvastatin can decrease serum level of MDA, AchE and ox-LDL, and increase that of SOD, Acb, and attenuate dementia symptom in AD, especially, with hyperlipemia. The hypothesis of atorvastatin neuroprotection is concluded that atorvastatin may restrain free radical reaction and retard oxidation in AD.

  2. Minocycline Attenuates Iron-Induced Brain Injury.

    Science.gov (United States)

    Zhao, Fan; Xi, Guohua; Liu, Wenqaun; Keep, Richard F; Hua, Ya

    2016-01-01

    Iron plays an important role in brain injury after intracerebral hemorrhage (ICH). Our previous study found minocycline reduces iron overload after ICH. The present study examined the effects of minocycline on the subacute brain injury induced by iron. Rats had an intracaudate injection of 50 μl of saline, iron, or iron + minocycline. All the animals were euthanized at day 3. Rat brains were used for immunohistochemistry (n = 5-6 per each group) and Western blotting assay (n = 4). Brain swelling, blood-brain barrier (BBB) disruption, and iron-handling proteins were measured. We found that intracerebral injection of iron resulted in brain swelling, BBB disruption, and brain iron-handling protein upregulation (p < 0.05). The co-injection of minocycline with iron significantly reduced iron-induced brain swelling (n = 5, p < 0.01). Albumin, a marker of BBB disruption, was measured by Western blot analysis. Minocycline significantly decreased albumin protein levels in the ipsilateral basal ganglia (p < 0.01). Iron-handling protein levels in the brain, including ceruloplasmin and transferrin, were reduced in the minocycline co-injected animals. In conclusion, the present study suggests that minocycline attenuates brain swelling and BBB disruption via an iron-chelation mechanism. PMID:26463975

  3. Statins attenuate polymethylmethacrylate-mediated monocyte activation.

    LENUS (Irish Health Repository)

    Laing, Alan J

    2012-02-03

    BACKGROUND: Periprosthetic osteolysis precipitates aseptic loosening of components, increases the risk of periprosthetic fracture and, through massive bone loss, complicates revision surgery and ultimately is the primary cause for failure of joint arthroplasty. The anti-inflammatory properties of HMG-CoA reductase inhibitors belonging to the statin family are well recognized. We investigated a possible role for status in initiating the first stage of the osteolytic cycle, namely monocytic activation. METHODS: We used an in vitro model of the human monocyte\\/macrophage inflammatory response to poly-methylmethacrylate (PMMA) particles after pretreat-ing cells with cerivastatin, a potent member of the statin family. Cell activation based upon production of TNF-alpha and MCP-1 cytokines was analyzed and the intracellular Raf-MEK-ERK signal transduction pathway was evaluated using western blot analysis, to identify its role in cell activation and in any cerivastatin effects observed. RESULTS: We found that pretreatment with cerivastatin significantly abrogates the production of inflammatory cytokines TNF-alpha and MCP-1 by human monocytes in response to polymethylmethacrylate particle activation. This inflammatory activation and attenuation appear to be mediated through the intracellular Raf-MEK-ERK pathway. INTERPRETATION: We propose that by intervening at the upstream activation stage, subsequent osteoclast activation and osteolysis can be suppressed. We believe that the anti-inflammatory properties of statins may potentially play a prophylactic role in the setting of aseptic loosening, and in so doing increase implant longevity.

  4. Persistent left superior vena cava draining to the left atrium: A case report and review of the literature

    International Nuclear Information System (INIS)

    Persistent left superior vena cava is a rare but important congenital vascular anomaly. However, PLSVC with absent RSVC (isolated PLSVC) is a very rare venous malformation We report on a rare case of persistent left superior vena cava (PLSVC) with absent right superior vena cava (RSVC). This venous malformation was identified incidentally in a 69-year-old woman during chest multi-detector computed tomography (MDCT). On chest MDCT, the SVC was noted on the left side. A bridging vein drained the right jugular and right subclavian veins and joined the left brachiocephalic vein in order to form the PLSVC, which descended on the left side of the mediastinum and drained into the left atrium (LA). The patient had no additional cardiac anomaly. Isolated PLSVC is usually asymptomatic but it can pose difficulties for establishing central venous access, pacemaker implantation and cardiothoracic surgery. This condition is also associated with an increased incidence of congenital heart disease, arrhythmias and conduction disturbances. A wide spectrum of clinicians should be aware of this anomaly, its variations and possible complications

  5. Left ventricular diverticulum with marked hypertrophy of the left ventricular apex revealed by thallium-201 myocardial emission CT

    International Nuclear Information System (INIS)

    A case of left ventricular apical diverticulum with marked hypertrophy of the left ventricular apical wall revealed by thallium-201 myocardial emission CT is reported. A 23-year-old woman was admitted to our hospital for evaluation of chest oppression. She was known to have had a heart murmur soon after birth, but she grew uneventfully, partaking in normal exercise. At the age of 21, she began to feel chest oppression during exercise. As the attacks became frequent, she was admitted to our hospital. Physical examination revealed an ejection systolic murmur in the second left intercostal space. Electrocardiography showed ST depression and T inversion in leads III, a VF and V4-6. M-mode echocardiography was normal. Two-dimensional echocardiography showed a small diverticulum at the apex of the left ventricle, which was also recognized by left ventriculography. It was about 8 x 12 mm in size. Thallium-201 myocardial emission CT disclosed marked uptake in the apex of the left ventricle, suggesting apical hypertrophy. Stress thallium-201 myocardial emission CT was negative. Coronary angiography was normal. The cause of chest oppression in this patient is uncertain, but the small diverticulum and hypertrophy of the cardiac apex may play a role in its pathogenesis. (author)

  6. CT findings of a displaced left upper division bronchus in adults: Its importance for performing safe left pulmonary surgery

    Energy Technology Data Exchange (ETDEWEB)

    Oshiro, Yasuji, E-mail: oshiro4211@yahoo.co.jp [Department of Radiology, National Hospital Organization Okinawa Hospital, 20-14 Ganeko 3-chome, Ginowan city, Okinawa 901-2214 (Japan); Murayama, Sadayuki [Department of Radiology, University of the Ryukus School of Medicine, 207 Uehara, Nishihara-cho, Okinawa 903-0215 (Japan); Ohta, Morio [Department of Surgery, Nakagami Hospital, 6-25-5 Chibana, Okinawa-city, Okinawa 904-2195 (Japan); Teruya, Takao [Second Department of Surgery, University of the Ryukus School of Medicine, 207 Uehara, Nishihara-cho, Okinawa 903-0215 (Japan)

    2013-08-15

    Purpose: The aim of this study was to describe the CT findings of a displaced left upper division bronchus (DLUDB) in adults. Materials and methods: Ten patients with DLUDB were identified. The following CT features were assessed: origin of the DLUDB; distance between the origin of the DLUDB and the origin of the left upper lobe (LUL) bronchus; height of the origin of the DLUDB against the left pulmonary artery (LPA); difference of the main bronchial length; ventilated segment; course of the left pulmonary artery against the DLUDB; and presence of an accessory fissure or other anomalies. Results: DLUDB arose from the posterolateral or lateral aspect of the left main bronchus immediately proximal to the origin of the LUL bronchus. It tended to course along the posterior wall of the LPA and to ventilate the apicoposterior segment with or without the anterior segment. The LPA passed between the displaced bronchus and the lingular bronchus. The origin of the DLUDB was located lower than the inferior wall of the proximal LPA in 6 patients. The accessory fissure between the associated segment and remaining part of the LUL and right tracheal bronchus coexisted in 7 and 3 patients respectively. Conclusion: DLUDB has characteristic findings on CT. Radiologists should be aware of this entity and inform the surgeon as it can prevent serious complications in a patient who may undergo lobectomy of the left lung.

  7. Repeated sauna therapy attenuates ventricular remodeling after myocardial infarction in rats by increasing coronary vascularity of noninfarcted myocardium.

    Science.gov (United States)

    Sobajima, Mitsuo; Nozawa, Takashi; Shida, Takuya; Ohori, Takashi; Suzuki, Takayuki; Matsuki, Akira; Inoue, Hiroshi

    2011-08-01

    Repeated sauna therapy (ST) increases endothelial nitric oxide synthase (eNOS) activity and improves cardiac function in heart failure as well as peripheral blood flow in ischemic limbs. The present study investigates whether ST can increase coronary vascularity and thus attenuate cardiac remodeling after myocardial infarction (MI). We induced MI by ligating the left coronary artery of Wistar rats. The rats were placed in a far-infrared dry sauna at 41°C for 15 min and then at 34°C for 20 min once daily for 4 wk. Cardiac hemodynamic, histopathological, and gene analyses were performed. Despite the similar sizes of MI between the ST and non-ST groups (51.4 ± 0.3 vs. 51.1 ± 0.2%), ST reduced left ventricular (LV) end-diastolic (9.7 ± 0.4 vs. 10.7 ± 0.5 mm, P myocardial atrial natriuretic peptide mRNA levels. Vascular density was reduced in the noninfarcted myocardium of non-ST rats, and the density of cells positive for CD31 and for α-smooth muscle actin was decreased. These decreases were attenuated in ST rats compared with non-ST rats and associated with increases in myocardial eNOS and vascular endothelial growth factor mRNA levels. In conclusion, ST attenuates cardiac remodeling after MI, at least in part, through improving coronary vascularity in the noninfarcted myocardium. Repeated ST might serve as a novel noninvasive therapy for patients with MI.

  8. Regional renal venous hypertension and left-sided varicocele

    Directory of Open Access Journals (Sweden)

    O. B. Zhukov

    2013-01-01

    Full Text Available One of the most frequent correctable causes of male infertility is a varicocele. The etiology and pathogenesis of varicocele to date is a matter of debate. The aim of our study was to determine the causes and incidence of regional renal hypertension in patients with leftsided varicocele. The study involved 110 patients with left-sided varicocele in age from 18 to 35 years. Algorithm for evaluation of patients with left-sided varicocele included: physical examination, ultrasound with Doppler kidney, basin area left renal vein, aorto-mesenteric portion; the scrotum with a sample Trombetta, phlebography аnd phlebotonometry basin left renal vein and the common iliac vein. Renospermatic reflux was detected in 89 (81 %, ileospermatic 12 (11 % and mixed 9 (8 % patients. Patients with reflux ileospermatic excluded from the study. The 96 patients with left-sided varicocele underwent venography and phlebotonometry in 37 (38.5 % were renal venous hypertension, with 35 of them that it was due to aorto-mesenteric compression, and in 2 cases an anomaly development – annular renal vein. Our data are comparable with the results of other authors. Patients with mesenteric compressed statistically significant reduction in the diameter of renal veins in the aorto-mesenteric portion and increased blood flow in this region, and expand prestenosis left renal vein and reduce flow velocity in this region compared with the group without renal phlebohypertension. Patients with renal phlebohypertension subsequently held shunt types of operations performed in patients with normotension occlusive types of operations. An integrated assessment of patients with left-side allows to make a holistic understanding of the basic mechanisms of disease etiology and select the appropriate type of surgery.

  9. Regional renal venous hypertension and left-sided varicocele

    Directory of Open Access Journals (Sweden)

    O. B. Zhukov

    2014-11-01

    Full Text Available One of the most frequent correctable causes of male infertility is a varicocele. The etiology and pathogenesis of varicocele to date is a matter of debate. The aim of our study was to determine the causes and incidence of regional renal hypertension in patients with leftsided varicocele. The study involved 110 patients with left-sided varicocele in age from 18 to 35 years. Algorithm for evaluation of patients with left-sided varicocele included: physical examination, ultrasound with Doppler kidney, basin area left renal vein, aorto-mesenteric portion; the scrotum with a sample Trombetta, phlebography аnd phlebotonometry basin left renal vein and the common iliac vein. Renospermatic reflux was detected in 89 (81 %, ileospermatic 12 (11 % and mixed 9 (8 % patients. Patients with reflux ileospermatic excluded from the study. The 96 patients with left-sided varicocele underwent venography and phlebotonometry in 37 (38.5 % were renal venous hypertension, with 35 of them that it was due to aorto-mesenteric compression, and in 2 cases an anomaly development – annular renal vein. Our data are comparable with the results of other authors. Patients with mesenteric compressed statistically significant reduction in the diameter of renal veins in the aorto-mesenteric portion and increased blood flow in this region, and expand prestenosis left renal vein and reduce flow velocity in this region compared with the group without renal phlebohypertension. Patients with renal phlebohypertension subsequently held shunt types of operations performed in patients with normotension occlusive types of operations. An integrated assessment of patients with left-side allows to make a holistic understanding of the basic mechanisms of disease etiology and select the appropriate type of surgery.

  10. Establishment of a chronic left ventricular aneurysm model in rabbit

    Institute of Scientific and Technical Information of China (English)

    Cang-Song XIAO; Chang-Qing GAO; Li-Bing LI; Yao WANG; Tao ZHAO; Wei-Hua YE; Chong-Lei REN; Zhi-Yong LIU; Yang WU

    2014-01-01

    Objectives To establish a cost-effective and reproducible procedure for induction of chronic left ventricular aneurysm (LVA) in rabbits. Methods Acute myocardial infarction (AMI) was induced in 35 rabbits via concomitant ligation of the left anterior descending (LAD) coronary artery and the circumflex (Cx) branch at the middle portion. Development of AMI was co n-firmed by ST segment elevation and akinesis of the occluded area. Echocardiography, pathological evaluation, and agar i n-tra-chamber casting were utilized to validate the formation of LVA four weeks after the surgery. Left ventricular end systolic pressure (LVESP) and diastolic pressure (LVEDP) were measured before, immediately after and four weeks after ligation. D i-mensions of the ventricular chamber, thickness of the interventricular septum (IVS) and the left ventricular posterior wall (LVPW) left ventricular end diastolic volume (LVEDV) and systolic volume (LVESV), and ejection fraction (EF) were recorded by echo-cardiography. Results Thirty one (88.6%) rabbits survived myocardial infarction and 26 of them developed aneurysm (83.9%). The mean area of aneurysm was 33.4% ± 2.4% of the left ventricle. LVEF markedly decreased after LVA formation, whereas LVEDV, LVESV and the thickness of IVS as well as the dimension of ventricular chamber from apex to mitral valve annulus significantly increased. LVESP immediately dropped after ligation and recovered to a small extent after LVA formation. LVEDP progressively increased after ligation till LVA formation. Areas in the left ventricle (LV) that underwent fibrosis included the apex, anterior wall and lateral wall but not IVS. Agar intra-chamber cast showed that the bulging of LV wall was prominent in the area of aneurysm. Conclusions Ligation of LAD and Cx at the middle portion could induce develo pment of LVA at a mean area ratio of 33.4%±2.4%which involves the apex, anterior wall and lateral wall of the LV.

  11. Broadband Lg Attenuation Modeling in the Middle East

    Energy Technology Data Exchange (ETDEWEB)

    Pasyanos, M E; Matzel, E M; Walter, W R; Rodgers, A J

    2008-08-21

    We present a broadband tomographic model of Lg attenuation in the Middle East derived from source- and site-corrected amplitudes. Absolute amplitude measurements are made on hand-selected and carefully windowed seismograms for tens of stations and thousands of crustal earthquakes resulting in excellent coverage of the region. A conjugate gradient method is used to tomographically invert the amplitude dataset of over 8000 paths over a 45{sup o} x 40{sup o} region of the Middle East. We solve for Q variation, as well as site and source terms, for a wide range of frequencies ranging from 0.5-10 Hz. We have modified the standard attenuation tomography technique to more explicitly define the earthquake source expression in terms of the seismic moment. This facilitates the use of the model to predict the expected amplitudes of new events, an important consideration for earthquake hazard or explosion monitoring applications. The attenuation results have a strong correlation to tectonics. Shields have low attenuation, while tectonic regions have high attenuation, with the highest attenuation at 1 Hz is found in eastern Turkey. The results also compare favorably to other studies in the region made using Lg propagation efficiency, Lg/Pg amplitude ratios and two-station methods. We tomographically invert the amplitude measurements for each frequency independently. In doing so, it appears the frequency-dependence of attenuation is not compatible with the power law representation of Q(f), an assumption that is often made.

  12. Rain Attenuation Prediction for Terrestrial Microwave Link in Bangladesh

    Directory of Open Access Journals (Sweden)

    HOSSAIN Sakir

    2014-05-01

    Full Text Available Rain attenuation is a major shortcoming of microwave transmission. As a subtropical country, Bangladesh is one of the highest rainy areas of the world. Thus, designing a terrestrial microwave link is a serious challenge to the engineers. In this paper, the annual rain rate and monthly variation of rate are predicted for different percentage of time of the year from the measured rainfall data. Using ITU rain model for terrestrial microwave communication, the rain attenuation is predicted for five major cities of Bangladesh, namely Dhaka, Chittagong, Rajshahi, Sylhet, and Khulna. It is found that rain attenuation is the most severe in Sylhet and least in Rajshahi. The attenuation is estimated for different frequency and polarization. A horizontally polarized signal encounters 15% more rain attenuation than that of vertically polarized signal. It is also found that attenuation in Rajshahi is about 20% lesser than that in Sylhet. Thus, the horizontally polarized transmission in Rajshahi experiences about 5% less attenuation than the vertically polarized transmission in Sylhet.

  13. Comparison of MR-based attenuation correction and CT-based attenuation correction of whole-body PET/MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Izquierdo-Garcia, David [Mount Sinai School of Medicine, Translational and Molecular Imaging Institute, New York, NY (United States); Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA (United States); Sawiak, Stephen J. [University of Cambridge, Wolfson Brain Imaging Centre, Cambridge (United Kingdom); Knesaurek, Karin; Machac, Joseph [Mount Sinai School of Medicine, Division of Nuclear Medicine, Department of Radiology, New York, NY (United States); Narula, Jagat [Mount Sinai School of Medicine, Department of Cardiology, Zena and Michael A. Weiner Cardiovascular Institute and Marie-Josee and Henry R. Kravis Cardiovascular Health Center, New York, NY (United States); Fuster, Valentin [Mount Sinai School of Medicine, Department of Cardiology, Zena and Michael A. Weiner Cardiovascular Institute and Marie-Josee and Henry R. Kravis Cardiovascular Health Center, New York, NY (United States); The Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid (Spain); Fayad, Zahi A. [Mount Sinai School of Medicine, Translational and Molecular Imaging Institute, New York, NY (United States); Mount Sinai School of Medicine, Department of Cardiology, Zena and Michael A. Weiner Cardiovascular Institute and Marie-Josee and Henry R. Kravis Cardiovascular Health Center, New York, NY (United States); Mount Sinai School of Medicine, Department of Radiology, New York, NY (United States)

    2014-08-15

    The objective of this study was to evaluate the performance of the built-in MR-based attenuation correction (MRAC) included in the combined whole-body Ingenuity TF PET/MR scanner and compare it to the performance of CT-based attenuation correction (CTAC) as the gold standard. Included in the study were 26 patients who underwent clinical whole-body FDG PET/CT imaging and subsequently PET/MR imaging (mean delay 100 min). Patients were separated into two groups: the alpha group (14 patients) without MR coils during PET/MR imaging and the beta group (12 patients) with MR coils present (neurovascular, spine, cardiac and torso coils). All images were coregistered to the same space (PET/MR). The two PET images from PET/MR reconstructed using MRAC and CTAC were compared by voxel-based and region-based methods (with ten regions of interest, ROIs). Lesions were also compared by an experienced clinician. Body mass index and lung density showed significant differences between the alpha and beta groups. Right and left lung densities were also significantly different within each group. The percentage differences in uptake values using MRAC in relation to those using CTAC were greater in the beta group than in the alpha group (alpha group -0.2 ± 33.6 %, R{sup 2} = 0.98, p < 0.001; beta group 10.31 ± 69.86 %, R{sup 2} = 0.97, p < 0.001). In comparison to CTAC, MRAC led to underestimation of the PET values by less than 10 % on average, although some ROIs and lesions did differ by more (including the spine, lung and heart). The beta group (imaged with coils present) showed increased overall PET quantification as well as increased variability compared to the alpha group (imaged without coils). PET data reconstructed with MRAC and CTAC showed some differences, mostly in relation to air pockets, metallic implants and attenuation differences in large bone areas (such as the pelvis and spine) due to the segmentation limitation of the MRAC method. (orig.)

  14. Comparison of MR-based attenuation correction and CT-based attenuation correction of whole-body PET/MR imaging

    International Nuclear Information System (INIS)

    The objective of this study was to evaluate the performance of the built-in MR-based attenuation correction (MRAC) included in the combined whole-body Ingenuity TF PET/MR scanner and compare it to the performance of CT-based attenuation correction (CTAC) as the gold standard. Included in the study were 26 patients who underwent clinical whole-body FDG PET/CT imaging and subsequently PET/MR imaging (mean delay 100 min). Patients were separated into two groups: the alpha group (14 patients) without MR coils during PET/MR imaging and the beta group (12 patients) with MR coils present (neurovascular, spine, cardiac and torso coils). All images were coregistered to the same space (PET/MR). The two PET images from PET/MR reconstructed using MRAC and CTAC were compared by voxel-based and region-based methods (with ten regions of interest, ROIs). Lesions were also compared by an experienced clinician. Body mass index and lung density showed significant differences between the alpha and beta groups. Right and left lung densities were also significantly different within each group. The percentage differences in uptake values using MRAC in relation to those using CTAC were greater in the beta group than in the alpha group (alpha group -0.2 ± 33.6 %, R2 = 0.98, p 2 = 0.97, p < 0.001). In comparison to CTAC, MRAC led to underestimation of the PET values by less than 10 % on average, although some ROIs and lesions did differ by more (including the spine, lung and heart). The beta group (imaged with coils present) showed increased overall PET quantification as well as increased variability compared to the alpha group (imaged without coils). PET data reconstructed with MRAC and CTAC showed some differences, mostly in relation to air pockets, metallic implants and attenuation differences in large bone areas (such as the pelvis and spine) due to the segmentation limitation of the MRAC method. (orig.)

  15. Molecular basis of live-attenuated influenza virus.

    Directory of Open Access Journals (Sweden)

    Wen He

    Full Text Available Human influenza is a seasonal disease associated with significant morbidity and mortality. The most effective means for controlling infection and thereby reducing morbidity and mortality is vaccination with a three inactivated influenza virus strains mixture, or by intranasal administration of a group of three different live attenuated influenza vaccine strains. Comparing to the inactivated vaccine, the attenuated live viruses allow better elicitation of a long-lasting and broader immune (humoral and cellular response that represents a naturally occurring transient infection. The cold-adapted (ca influenza A/AA/6/60 (H2N2 (AA ca virus is the backbone for the live attenuated trivalent seasonal influenza vaccine licensed in the United States. Similarly, the influenza A components of live-attenuated vaccines used in Russia have been prepared as reassortants of the cold-adapted (ca H2N2 viruses, A/Leningrad/134/17/57-ca (Len/17 and A/Leningrad/134/47/57-ca (Len/47 along with virulent epidemic strains. However, the mechanism of temperature-sensitive attenuation is largely elusive. To understand how modification at genetic level of influenza virus would result in attenuation of human influenza virus A/PR/8/34 (H1N1,A/PR8, we investigated the involvement of key mutations in the PB1 and/or PB2 genes in attenuation of influenza virus in vitro and in vivo. We have demonstrated that a few of residues in PB1 and PB2 are critical for the phenotypes of live attenuated, temperature sensitive influenza viruses by minigenome assay and real-time PCR. The information of these mutation loci could be used for elucidation of mechanism of temperature-sensitive attenuation and as a new strategy for influenza vaccine development.

  16. Seismic attenuation: Laboratory measurements in fluid saturated rocks

    Science.gov (United States)

    Subramaniyan, Shankar; Madonna, Claudio; Tisato, Nicola; Saenger, Erik; Quintal, Beatriz

    2014-05-01

    Seismic wave attenuation could be used as an indicator of reservoir fluids due to its dependence on rock and fluid properties. Over the past 30 years, many laboratory methodologies to study attenuation in rocks have been employed, such as ultrasonic (MHz), resonant bar (kHz) and forced oscillation methods in the low frequency range (0.01-100Hz) (Tisato & Madonna 2012; Madonna & Tisato 2013). Forced oscillation methods have gained prominence over time as the frequency range of measurements correspond to that of field seismic data acquired for oil/gas exploration. These experiments measure attenuation as the phase shift between the applied stress (sinusoidal) and measured strain. Since the magnitudes of measured phase shifts are quite low (Q-1 ~0.01-0.1) and the amplitudes of strain applied to the rock samples are of the order ~10-6 (i.e., similar orders of magnitude to seismic waves), it is challenging. A comparison of such forced oscillation setups will be presented to provide an overview of the various possibilities of design and implementation for future setups. In general, there is a lack of laboratory data and most of the published data are for sandstones. Currently, attenuation measurements are being carried out on carbonate and sandstone samples. We employ the Seismic Wave Attenuation Module (SWAM, Madonna & Tisato 2013) to measure seismic attenuation in these samples for different saturation degrees (90% and 100% water) and under three different confining pressures (5, 10 and 15MPa). Preliminary results from these investigations will be discussed. REFERENCES Madonna, C. & Tisato, N. 2013: A new seismic wave attenuation module to experimentally measure low-frequency attenuation in extensional mode. Geophysical Prospecting, doi: 10.1111/1365-2478.12015. Tisato, N. & Madonna, C. 2012: Attenuation at low seismic frequencies in partially saturated rocks: Measurements and description of a new apparatus. Journal of Applied Geophysics, 86, 44-53.

  17. Reflection and Refraction on the Boundary of a Left-Handed Material with a Hyperbolic Dispersion Relation

    Institute of Scientific and Technical Information of China (English)

    ZHONG Yu; SHEN Lin-Fang; RAN Li-Xin; CHEN Xu-Dong; Liisi Jylh(a); Tomasz M. Grzegorczyk; Jin Au Kong

    2006-01-01

    @@ Wave reflection and refraction at the interface between a normal media and a one-dimensional left-handed material (1 DLHM) with a hyperbolic dispersion relationship is studied. It is found that in a special case that the boundary is perpendicular to one asymptotic line of the hyperbola, phase matching cannot be achieved unless the 1 DLHM is regarded to be intrinsically lossy. After introducing a small loss factor to the 1 DLHM, a reasonable solution for the phase matching is obtained. According to the analytical result, a wave confined to a thin layer near the boundary is found, which can be excited at the interface as a reflected wave or a refracted wave attenuating drastically away from the boundary inside the 1 DLHM in both cases.

  18. Hydrosulfide attenuates acute myocardial ischemic injury through the glycogen synthase kinase-3β/β-catenin signaling pathway.

    Science.gov (United States)

    Ge, Ning; Liu, Chao; Li, Guofeng; Xie, Lijun; Zhang, Qinzeng; Li, Liping; Hao, Na; Zhang, Jianxin

    2016-05-01

    The endogenous signaling gasotransmitter, hydrosulfide (H2S), has been shown to exert cardioprotective effects against acute myocardial infarction (AMI) due to ischemic injury. However, the mechanisms responsible for these effects are not yet fully understood. In this study, we investigated whether sodium hydrogen sulfide (NaHS), an H2S donor, attenuates acute myocardial ischemic injury through glycogen synthase kinase-3β (GSK-3β)/β-catenin signaling. For this purpose, we utilized an in vivo rat model of AMI by occluding the left anterior descending coronary artery. NaHS (0.39, 0.78 or 1.56 mg/kg, intraperitoneally), the GSK-3β inhibitor, SB216763 (0.6 mg/kg, intravenously), or 1% dimethylsulfoxide (2 ml/kg, intravenously) were administered to the rats. The results demonstrated that the administration of medium- and high-dose NaHS and SB216763 significantly improved rat cardiac function, as evidenced by an increase in the mean arterial pressure, left ventricular developed pressure, contraction and relaxation rates, as well as a decrease in left ventricular end-diastolic pressure. In addition, the administration of NaHS and SB216763 attenuated myocardial injury as reflected by a decrease in apoptotic cell death and in the serum lactate dehydrogenase concentrations, and prevented myocardial structural changes. The administration of NaHS and SB216763 increased the concentrations of phosphorylated (p-)GSK-3β, the p-GSK-3β/t-GSK-3β ratio and downstream protein β-catenin. Moreover, western blot and immunohistochemical analyses of apoptotic signaling pathway proteins further established the cardioprotective potential of NaHS, as reflected by the upregulation of Bcl-2 expression, the downregulation of Bax expression, and a decrease in the number of TUNEL-positive stained cells. These findings suggest that hydrosulfide exerts cardioprotective effects against AMI-induced apoptosis through the GSK-3β/β-catenin signaling pathway.

  19. Photon attenuation properties of some thorium, uranium and plutonium compounds

    Energy Technology Data Exchange (ETDEWEB)

    Singh, V. P.; Badiger, N. M. [Karnatak University, Department of Physics, Dharwad-580003, Karnataka (India); Vega C, H. R., E-mail: kudphyvps@rediffmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas, Zac. (Mexico)

    2015-10-15

    Mass attenuation coefficients, effective atomic numbers, effective electron densities for nuclear materials; thorium, uranium and plutonium compounds have been studied. The photon attenuation properties for the compounds have been investigated for partial photon interaction processes by photoelectric effect, Compton scattering and pair production. The values of these parameters have been found to change with photon energy and interaction process. The variations of mass attenuation coefficients, effective atomic number and electron density with energy are shown graphically. Moreover, results have shown that these compounds are better shielding and suggesting smaller dimensions. The study would be useful for applications of these materials for gamma ray shielding requirement. (Author)

  20. FSO and radio link attenuation: meteorological models verified by experiment

    Science.gov (United States)

    Brazda, Vladimir; Fiser, Ondrej; Svoboda, Jaroslav

    2011-09-01

    Institute of Atmospheric Physics of Czech Academy measures atmospheric attenuation on 60 m experimental FSO link on 830 and 1550 nm for more than three years. Visibility sensors and two 3D sonic anemometers on both transmitting and receiving site, rain gauge and many sensors enabling the refractivity index computation are spaced along the optical link. Meteorological visibility, wind turbulent energy, sonic temperature, structure index and rain rate are correlated with measured attenuation. FSO link attenuation dependence on the above mentioned parameters is analyzed. The paper shows also basic statistical behavior of the long-term FSO signal level and also the simulation of hybrid link techniques.

  1. PID Gain Tuning for Disturbance Attenuation FRIT Method

    Science.gov (United States)

    Masuda, Shiro

    This review paper shows a PID gains tuning method from one-shot experimental data generated by test signal added at input signal in an off-line manner, so that the output signal could follow the prescribed reference model output. We call the method a “disturbance attenuation FRIT method” because the test signal added at input signal is a benchmark signal evaluating disturbance attenuation property. The experimental result for helicopter attitude control model is demonstrated to show the effectiveness of the disturbance attenuation FRIT method.

  2. Esmolol vs. nitroglycerin: attenuating hemodynamic response to laryngoscopy and intubation

    Directory of Open Access Journals (Sweden)

    Cassie Held

    2016-01-01

    Full Text Available Hemodynamic response to laryngoscopy and intubation is a common occurrence with the potential for harmful effects. Many drugs have been utilized throughout the years to attenuate this response with mixed results. This review compares the efficacy of two drugs, esmolol and nitroglycerin, in attenuating hemodynamic response to laryngoscopy and intubation. A systematic review was performed compiling all previous studies detailing the efficacy of esmolol in comparison to nitroglycerin for this purpose. Esmolol was found to consistently attenuate hemodynamic responses of blood pressure and heart rate with greater efficacy than nitroglycerin, and is thus recommended over nitroglycerin for use in this role.

  3. MNAtoolbox: A Monitored Natural Attenuation Site Screening Program

    Energy Technology Data Exchange (ETDEWEB)

    Borns, David J.; Brady, Patrick V.; Brady, Warren D.; Krupka, Kenneth M.; Spalding, Brian P.; Waters, Robert D.; Zhang, Pengchu

    1999-07-12

    Screening of sites for the potential application and reliance upon monitored natural attenuation (MNA) can be done using MNAtoolbox, a web-based tool for estimating extent of biodegradation, chemical transformation, and dilution. MNAtoolbox uses site-specific input data, where available (default parameters are taken from the literature), to roughly quantify the nature and extent of attenuation at a particular site. Use of MNAtoolbox provides 3 important elements of site evaluation: (1) Identifies likely attenuation pathways, (2) Clearly identifies sites where MNA is inappropriate, and (3) Evaluates data requirements for subsequent reliance on MNA as a sole or partial corrective action.

  4. Improving EMI Attenuation in Frequency Modulated Power Converters

    OpenAIRE

    Stepins, D.

    2009-01-01

    The effect of frequency modulation on a power switching converter electromagnetic interference (EMI) attenuation is examined in this paper. A method known as “modified sawtooth” is applied for EMI attenuation in a boost converter and it is optimized in such a way to reduce EMI more effectively. The method is also verified experimentally by the use of a low power boost converter controlled via an arbitrary waveform generator. EMI attenuation up to 15 dB is achieved after using modified sawtoot...

  5. Ultrasonic attenuation measurements determine onset, degree, and completion of recrystallization

    Science.gov (United States)

    Generazio, E. R.

    1988-01-01

    Ultrasonic attenuation was measured for cold worked Nickel 200 samples annealed at increasing temperatures. Localized dislocation density variations, crystalline order and volume percent of recrystallized phase were determined over the anneal temperature range using transmission electron microscopy, X-ray diffraction, and metallurgy. The exponent of the frequency dependence of the attenuation was found to be a key variable relating ultrasonic attenuation to the thermal kinetics of the recrystallization process. Identification of this key variable allows for the ultrasonic determination of onset, degree, and completion of recrystallization.

  6. Dispersion effects on infrared spectra in attenuated total reflection

    Science.gov (United States)

    Belali, Rabah; Vigoureux, Jean-Marie; Morvan, Joseph

    1995-12-01

    A potential problem with the attenuated total reflection that is used to measure infrared spectra is described. The problem is the possibility that the anomalous dispersion associated with an infrared absorption band may cause the experimental configuration to move from the attenuated total reflection regime to the specular reflection regime, with consequent distortion of the apparent absorption bands and consequent error in the interpretation of the bands if the problem is not recognized. Key infrared spectra, attenuated total reflection, specular reflection, polyethylene terephtalate. Copyright (c) 1995 Optical Society of America

  7. Photon attenuation properties of some thorium, uranium and plutonium compounds

    International Nuclear Information System (INIS)

    Mass attenuation coefficients, effective atomic numbers, effective electron densities for nuclear materials; thorium, uranium and plutonium compounds have been studied. The photon attenuation properties for the compounds have been investigated for partial photon interaction processes by photoelectric effect, Compton scattering and pair production. The values of these parameters have been found to change with photon energy and interaction process. The variations of mass attenuation coefficients, effective atomic number and electron density with energy are shown graphically. Moreover, results have shown that these compounds are better shielding and suggesting smaller dimensions. The study would be useful for applications of these materials for gamma ray shielding requirement. (Author)

  8. Etiological aspect of left-handedness in adolescents

    Directory of Open Access Journals (Sweden)

    Dragović Milan

    2013-01-01

    Full Text Available Introduction. Lateralization of brain functions such as language and manual dominance (hand preferences and fine motor control are most likely under genetic control. However, this does not preclude the effect of various environmental factors on functional brain lateralization. A strong association of non-right-handedness (left- and mixed-handedness with various neurodevelopmental conditions (e.g. schizophrenia, autism, Rett syndrome implies that in some cases, non-right-handedness may be acquired rather than inherited (i.e., pathologically determined. Objective. The aim of the study was: (a re-investigation of several known risk factors for left-handedness (age of mother and/or father, twin pregnancies, and birth order, and (b examination of hitherto uninvestigated factors (type of birth, Apgar score, maternal smoking during pregnancy. Methods. Putative, causative environmental agents for this shift in manual distributions are explored in a sample of 1031 high school students (404 males and 627 females from Belgrade. Both pre-existing (age of parents, twin pregnancy, and birth order and new (Apgar score, maternal smoking, type of birth putative agents are examined. Results. We found that maternal smoking and low Apgar score (2-6 can significantly increase risk for left-handedness (p=0.046 and p=0.042, respectively. The remaining factors showed no significant association with left-handedness in adolescents. Conclusion. Our study clearly demonstrates that left-handedness may be related to maternal smoking during pregnancy and a low Apgar score on birth.

  9. Social stereotyping of left-handers in Serbia.

    Science.gov (United States)

    Dragović, Milan; Badcock, Johanna C; Sanja, Milenković; Gregurović, Margareta; Šram, Zlatko

    2013-01-01

    Social tolerance towards left-handed people is commonly accepted in the twenty-first century, though not universal. However, at the level of social cognition a subtle bias against this visible minority group might not have disappeared. To investigate this possibility we adopted the theoretical framework of the stereotype content model (SCM) whereby two fundamental dimensions (warmth and competence) are sufficient to explain group differences in stereotype content. We examined how a large sample of medical students (N=300) perceived nine social groups (seven with various physical, social, or mental handicaps, and the two target groups of left- and right-handers), and four "anchor" groups comprising educated people, pensioners, drug addicts, and rich people) which are considered as prototypical in terms of the SCM. Hierarchical cluster analysis was performed to determine similarity of groups in the warmth × competence two-dimensional space. Four clusters were identified, with left- and right-handers located in the same cluster together with educated people. This cluster had higher ratings on both warmth and competence (i.e., more positive stereotype) compared with all other groups. However, within-cluster analysis showed that the left-handed group was perceived as lower on both dimensions compared to the right-handed group. This statistically significant difference suggests that implicit bias against left-handed individuals has not vanished despite pervasive social tolerance. Possible mechanisms that may explain this subtle and subliminal stereotyping are discussed. PMID:23391021

  10. Social stereotyping of left-handers in Serbia.

    Science.gov (United States)

    Dragović, Milan; Badcock, Johanna C; Sanja, Milenković; Gregurović, Margareta; Šram, Zlatko

    2013-01-01

    Social tolerance towards left-handed people is commonly accepted in the twenty-first century, though not universal. However, at the level of social cognition a subtle bias against this visible minority group might not have disappeared. To investigate this possibility we adopted the theoretical framework of the stereotype content model (SCM) whereby two fundamental dimensions (warmth and competence) are sufficient to explain group differences in stereotype content. We examined how a large sample of medical students (N=300) perceived nine social groups (seven with various physical, social, or mental handicaps, and the two target groups of left- and right-handers), and four "anchor" groups comprising educated people, pensioners, drug addicts, and rich people) which are considered as prototypical in terms of the SCM. Hierarchical cluster analysis was performed to determine similarity of groups in the warmth × competence two-dimensional space. Four clusters were identified, with left- and right-handers located in the same cluster together with educated people. This cluster had higher ratings on both warmth and competence (i.e., more positive stereotype) compared with all other groups. However, within-cluster analysis showed that the left-handed group was perceived as lower on both dimensions compared to the right-handed group. This statistically significant difference suggests that implicit bias against left-handed individuals has not vanished despite pervasive social tolerance. Possible mechanisms that may explain this subtle and subliminal stereotyping are discussed.

  11. Left and right in the Bible from a neuropsychological perspective.

    Science.gov (United States)

    Fabbro, F

    1994-03-01

    Although in several neuropsychological works dealing with hemispheric specializations a few passages of the Bible referring to the left and the right have been mentioned now and then, a systematical study with a neuropsychological approach to this topic was still a missing link. By using concordance texts from the Bible books of the Hebrew Canon (Old Testament, OT) and from the New Testament (NT), all the verses containing any reference to the left and the right (OT = 151, NT = 49 verses) have been identified and classified into 10 groups: (1) references to space, (2) symmetric sayings, (3) the right hand is the favorite hand, (4) right eye preference, (5) God's right hand, (6) the right side is more prestigious, (7) the right side in liturgy, (8) left hand preference, (9) fatal left-hand shots, and (10) on the left side. Some statistical considerations have been put forward and a neuropsychological, anthropological approach has been suggested for the purpose of interpreting the most interesting verses. According to the author of the present paper, it would be worthwhile commenting on some texts of ancient and modern literature not only from a linguistic, historical, religious and theological point of view, but also by means of a neuropsychological approach.

  12. Prevalence of left-sided melanomas in an Irish population.

    LENUS (Irish Health Repository)

    de Blacam, C

    2012-02-01

    BACKGROUND: A predominance of melanomas on the left side of the body has recently been described. No associations between tumour laterality and gender, age or anatomical site have been identified. AIM: The aim of this study was to investigate the prevalence of left-sided melanomas in an Irish population and to examine potential associations with various patient and tumour characteristics. METHODS: A retrospective chart review of patients with cutaneous melanoma who were treated over a 10-year period was carried out. Lateral distribution of melanoma on either side of the body was compared using chi(2) analysis and evaluated by gender, age group, anatomic location, histologic subtype and Breslow depth. RESULTS: More melanomas occurred on the left side (57%, P = 0.015), and this finding was particularly significant in females. For both genders combined, there were no statistically significant differences in laterality by age group, anatomic location, type of melanoma and Breslow depth. There were significantly more superficial spreading melanomas on the left side in both men and women. CONCLUSIONS: This study demonstrates a predominance of left-sided melanomas in Irish patients. While a number of demographic and molecular associations have been proposed, further research is required to fully explain this phenomenon.

  13. Prevalence of left-sided melanomas in an Irish population.

    LENUS (Irish Health Repository)

    de Blacam, C

    2011-04-17

    BACKGROUND: A predominance of melanomas on the left side of the body has recently been described. No associations between tumour laterality and gender, age or anatomical site have been identified. AIM: The aim of this study was to investigate the prevalence of left-sided melanomas in an Irish population and to examine potential associations with various patient and tumour characteristics. METHODS: A retrospective chart review of patients with cutaneous melanoma who were treated over a 10-year period was carried out. Lateral distribution of melanoma on either side of the body was compared using χ(2) analysis and evaluated by gender, age group, anatomic location, histologic subtype and Breslow depth. RESULTS: More melanomas occurred on the left side (57%, P = 0.015), and this finding was particularly significant in females. For both genders combined, there were no statistically significant differences in laterality by age group, anatomic location, type of melanoma and Breslow depth. There were significantly more superficial spreading melanomas on the left side in both men and women. CONCLUSIONS: This study demonstrates a predominance of left-sided melanomas in Irish patients. While a number of demographic and molecular associations have been proposed, further research is required to fully explain this phenomenon.

  14. A report of left dorsal displacement of the large colon in a tropical horse

    Directory of Open Access Journals (Sweden)

    Farhang Sasani

    2013-04-01

    Full Text Available We report one such case which was diagnosed intraoperatively as left dorsal colon volvulus due to multiple mesenteric abnormalities. A 17-year-old castrated male horse was taken to the Tehran University Veterinary Hospital for treatment of metacarpal wound accompanied by severe abdominal distension and acute colic. The treatment and measurement were taken for a month, and the prepared biopsy indicated that the healing trend was obvious. Unfortunately, prior to discharge, the clinical colic manifestations emerged and the animal suddenly died. Dilated large intestine was palpated per rectum and a ventral midline exploratory laparotomy was performed, a complete volvulus of the ascending colon was identified with multiple mesenteric anomalies of unknown aetiology. The pathologic changes observed in this study accurately reflect those changes reported in horse with naturally occurring colonic volvulus and can serve as a reference for subsequent studies on attenuating bowel injury. The present study results can be used to make a scientific assessment of prognosis in the pre-operative, operative, and post-operative management of horses with large colon volvulus.

  15. Cardiac left ventricular function before and during early thyroxine treatment in severe hypothyroidism.

    Science.gov (United States)

    Bernstein, R; Müller, C; Midtbø, K; Haug, E; Nakken, K F; Hertzenberg, L; Kjørstad, K E

    1991-12-01

    In some patients with severe hypothyroidism, thyroxine replacement therapy precipitates or aggravates angina pectoris, whereas in other patients angina pectoris is ameliorated or even cured. Cardiac function in eight severely hypothyroid patients was studied by means of radionuclide ventriculography (RNV) at rest and during supine bicycle exercise before thyroxine treatment, and repeated during treatment before and after administration of 160 mg of oral verapamil. There was an exercise-induced fall in left ventricular ejection fraction (LVEF) in two patients before therapy, and in two additional subjects after 17 d on suboptimal doses of thyroxine. Verapamil attenuated the fall and induced a significant increase in LVEF during exercise (P less than 0.014). No abnormal regional cardiac wall movement (RWM) was observed. After 2 months of thyroxine treatment, LVEF increased significantly during exercise both before and after verapamil (P less than 0.012 and P less than 0.005). These findings are indicative of reversible coronary artery dysfunction. We recommend that, if feasible, thyroxine should be supplemented with verapamil during the early phase of treatment. PMID:1748858

  16. A report of left dorsal displacement of the large colon in a tropical horse

    Institute of Scientific and Technical Information of China (English)

    Farhang; Sasani; Javad; Javanbakht; Mehdi; Ghamsari; Mehdi; Aghamohammad; Hassan

    2013-01-01

    We report one such case which was diagnosed intraoperatively as left dorsal colon volvulus due to multiple mesenteric abnormalities.A 17-year-old castrated male horse was taken to the Tehran University Veterinary Hospital for treatment of metacarpal wound accompanied by severe abdominal distension and acute colic.The treatment and measurement were taken for a month,and the prepared biopsy indicated that the healing trend was obvious.Unfortunately,prior to discharge,the clinical colic manifestations emerged and the animal suddenly died.Dilated large intestine was palpated per rectum and a ventral midline exploratory laparotomy was performed,a complete volvulus of the ascending colon was identified with multiple mesenteric anomalies of unknown aetiology.The pathologic changes observed in this study accurately reflect those changes reported in horse with naturally occurring colonic volvulus and can serve as a reference for subsequent studies on attenuating bowel injury.The present study results can be used to make a scientific assessment of prognosis in the pre-operative,operative,and post-operative management of horses with large colon volvulus.

  17. Pyrvinium attenuates Hedgehog signaling downstream of smoothened.

    Science.gov (United States)

    Li, Bin; Fei, Dennis Liang; Flaveny, Colin A; Dahmane, Nadia; Baubet, Valérie; Wang, Zhiqiang; Bai, Feng; Pei, Xin-Hai; Rodriguez-Blanco, Jezabel; Hang, Brian; Orton, Darren; Han, Lu; Wang, Baolin; Capobianco, Anthony J; Lee, Ethan; Robbins, David J

    2014-09-01

    The Hedgehog (HH) signaling pathway represents an important class of emerging developmental signaling pathways that play critical roles in the genesis of a large number of human cancers. The pharmaceutical industry is currently focused on developing small molecules targeting Smoothened (Smo), a key signaling effector of the HH pathway that regulates the levels and activity of the Gli family of transcription factors. Although one of these compounds, vismodegib, is now FDA-approved for patients with advanced basal cell carcinoma, acquired mutations in Smo can result in rapid relapse. Furthermore, many cancers also exhibit a Smo-independent activation of Gli proteins, an observation that may underlie the limited efficacy of Smo inhibitors in clinical trials against other types of cancer. Thus, there remains a critical need for HH inhibitors with different mechanisms of action, particularly those that act downstream of Smo. Recently, we identified the FDA-approved anti-pinworm compound pyrvinium as a novel, potent (IC50, 10 nmol/L) casein kinase-1α (CK1α) agonist. We show here that pyrvinium is a potent inhibitor of HH signaling, which acts by reducing the stability of the Gli family of transcription factors. Consistent with CK1α agonists acting on these most distal components of the HH signaling pathway, pyrvinium is able to inhibit the activity of a clinically relevant, vismodegib -resistant Smo mutant, as well as the Gli activity resulting from loss of the negative regulator suppressor of fused. We go on to demonstrate the utility of this small molecule in vivo, against the HH-dependent cancer medulloblastoma, attenuating its growth and reducing the expression of HH biomarkers. PMID:24994715

  18. Acetate supplementation attenuates lipopolysaccharide-induced neuroinflammation.

    Science.gov (United States)

    Reisenauer, Chris J; Bhatt, Dhaval P; Mitteness, Dane J; Slanczka, Evan R; Gienger, Heidi M; Watt, John A; Rosenberger, Thad A

    2011-04-01

    Glyceryl triacetate (GTA), a compound effective at increasing circulating and tissue levels of acetate was used to treat rats subjected to a continual 28 day intra-ventricular infusion of bacterial lipopolysaccharide (LPS). This model produces a neuroinflammatory injury characterized by global neuroglial activation and a decrease in choline acetyltransferase immunoreactivity in the basal forebrain. During the LPS infusion, rats were given a daily treatment of either water or GTA at a dose of 6 g/kg by oral gavage. In parallel experiments, free-CoA and acetyl-CoA levels were measured in microwave fixed brains and flash frozen heart, liver, kidney and muscle following a single oral dose of GTA. We found that a single oral dose of GTA significantly increased plasma acetate levels by 15 min and remained elevated for up to 4 h. At 30 min the acetyl-CoA levels in microwave-fixed brain and flash frozen heart and liver were increased at least 2.2-fold. The concentrations of brain acetyl-CoA was significantly increased between 30 and 45 min following treatment and remained elevated for up to 4 h. The concentration of free-CoA in brain was significantly decreased compared to controls at 240 min. Immunohistochemical and morphological analysis demonstrated that a daily treatment with GTA significantly reduced the percentage of reactive glial fibrillary acidic protein-positive astrocytes and activated CD11b-positive microglia by 40-50% in rats subjected to LPS-induced neuroinflammation. Further, in rats subjected to neuroinflammation, GTA significantly increased the number of choline acetyltransferase (ChAT)-positive cells by 40% in the basal forebrain compared to untreated controls. These data suggest that acetate supplementation increases intermediary short chain acetyl-CoA metabolism and that treatment is potentially anti-inflammatory and neuroprotective with regards to attenuating neuroglial activation and increasing ChAT immunoreactivity in this model. PMID:21272004

  19. Circumaortic Left Renal Vein-A Rare Case Report

    Science.gov (United States)

    Panagar, Anupama Doddappaiah; Subhash, R. Lakshmi Prabha; Suresh, B.S.; Nagaraj, D.N.

    2014-01-01

    During routine dissection which was carried out for the medical students, a circumaortic left renal vein draining into inferior vena cava was observed. There were 2 renal veins through which the left kidney drained into the inferior vena cava, of which the larger one ran ventral to aorta and the other smaller one ran posterior to aorta and received lumbar veins before opening into inferior vena cava. This is a relatively rare condition which can result in left renal hypertension (LRVH) syndrome which is otherwise called as anterior and posterior nutcracker syndromes. This venous anomaly results from the errors of embryological development. It is of clinical significance, mainly during retroperitoneal surgeries and intra caval interventions. It is also important in conditions which warrant extensive venous dissections, venous reconstructions as in transplantations and invasion of veins by cancerous tissue, resulting in life threatening haemorrhage. PMID:24783096

  20. Left-Handed W Bosons at the LHC

    CERN Document Server

    Bern, Z; Dixon, L J; Cordero, F Febres; Forde, D; Gleisberg, T; Hoeche, S; Ita, H; Kosower, D A; Maitre, D; Ozeren, K

    2011-01-01

    The production of W bosons in association with jets is an important background to new physics at the LHC. Events in which the W carries large transverse momentum and decays leptonically lead to large missing energy and are of particular importance. We show that the left-handed nature of the W coupling, combined with valence quark domination at a pp machine, leads to a large left-handed polarization for both W^+ and W^- bosons at large transverse momenta. The polarization fractions are very stable with respect to QCD corrections. The leptonic decay of the W bosons translates the common left-handed polarization into a strong asymmetry in transverse momentum distributions between positrons and electrons, and between neutrinos and anti-neutrinos (missing transverse energy). Such asymmetries may provide an effective experimental handle on separating W + jets from top quark production, which exhibits very little asymmetry due to C invariance, and from various types of new physics.

  1. Left-Right Entanglement Entropy of Dp-branes

    CERN Document Server

    Zayas, Leopoldo A Pando

    2016-01-01

    We compute the left-right entanglement entropy for Dp-branes in string theory. We employ the CFT approach to string theory Dp-branes, in particular, its presentation as coherent states of the closed string sector. The entanglement entropy is computed as the von Neumann entropy for a density matrix resulting from integration over the left-moving degrees of freedom. We discuss various crucial ambiguities related to sums over spin structures and argue that different choices capture different physics. We also consider Dp branes on compact dimensions and verify that the effects of T-duality act covariantly on the Dp brane entanglement entropy. We find that generically the left-right entanglement entropy provides a suitable generalization of boundary entropy and of the D-brane tension.

  2. Anomalous right coronary artery arising from left anterior descending artery

    Directory of Open Access Journals (Sweden)

    M.L. Sreenivas Kumar

    2012-07-01

    Full Text Available A 54-year-old male patient presented with acute myocardial infarction involving left anterior descending and right coronary artery territories. Coronary angiogram showed a single coronary artery with right coronary artery arising from left anterior descending artery (LAD, which coursed anterior to right ventricular outflow tract and thrombotic lesion in mid left anterior descending artery before origin of right coronary artery. The patient was treated with thrombolytic therapy and glycoprotein IIb/IIIa inhibitors. Anomalous origin of right coronary artery as a branch of LAD is a very rare type of congenital coronary artery anomalies. It is important to recognize this anomaly as it can be associated with extensive myocardial ischemia and sudden cardiac death in young persons even without atherosclerosis.

  3. Organic mood disorder following left anterior temporal lobectomy with amygdalohippocampectomy

    Directory of Open Access Journals (Sweden)

    Nishanth J Haridas

    2015-01-01

    Full Text Available One third of patients with antiepileptic-resistant temporal lobe epilepsy (TLE will have to undergo surgery for a better seizure control. Anterior temporal lobectomy (ATL is done for mesial temporal sclerosis that is the most common histopathological lesion associated with TLE. Psychiatric manifestations following ATL are not uncommon with depressive symptoms more common with left ATL and manic symptoms following right ATL. Mr. A is a 42-year-old left cerebral dominant (Confirmed by WADA test male with no past history of psychiatric illness who had undergone anterior temporal lobectomy with amygdalohippocampectomy. He started having manic episodes post operatively which subsided with antipsychotics. He had multiple such episodes over the next 13 years with minimal inter episodic symptoms. This is a rare instance of manic symptoms following left-sided ATL that emphasizes the need for better understanding of the cerebral laterality of affective symptoms.

  4. Normal left atrial dimensions in indians by echo-cardiography

    Directory of Open Access Journals (Sweden)

    Kulkarni D

    1979-01-01

    Full Text Available One hundred normal Indian subjects were studied to establish the normal left atrial dimension (LAD, left atrial dimension cor-rected to body surface area (LA index and left atrium to aorta ratio (LA/AO for this population. Normal mean LAD was 21.9 ± 3.6 mm (12 mm to 30 mm. Elderly subjects had higher mean LAD (25.2 ± 3.6 mm. The LA index for adults was 14.1 ± 2.5 mm. LA index for younger subjects was higher because of low body sur-face area. Mean LA/AO was 0.95± 0.22;LA/AO greater than 1.17 is suggested as a criterion for LA enlargement.

  5. Caffeine improves left hemisphere processing of positive words.

    Directory of Open Access Journals (Sweden)

    Lars Kuchinke

    Full Text Available A positivity advantage is known in emotional word recognition in that positive words are consistently processed faster and with fewer errors compared to emotionally neutral words. A similar advantage is not evident for negative words. Results of divided visual field studies, where stimuli are presented in either the left or right visual field and are initially processed by the contra-lateral brain hemisphere, point to a specificity of the language-dominant left hemisphere. The present study examined this effect by showing that the intake of caffeine further enhanced the recognition performance of positive, but not negative or neutral stimuli compared to a placebo control group. Because this effect was only present in the right visual field/left hemisphere condition, and based on the close link between caffeine intake and dopaminergic transmission, this result points to a dopaminergic explanation of the positivity advantage in emotional word recognition.

  6. Left-right correlation in coupled F-center defects

    Science.gov (United States)

    Janesko, Benjamin G.

    2016-08-01

    This work explores how left-right correlation, a textbook problem in electronic structure theory, manifests in a textbook example of electrons trapped in crystal defects. I show that adjacent F-center defects in lithium fluoride display symptoms of "strong" left-right correlation, symptoms similar to those seen in stretched H2. Simulations of UV/visible absorption spectra qualitatively fail to reproduce experiment unless left-right correlation is taken into account. This is of interest to both the electronic structure theory and crystal-defect communities. Theorists have a new well-behaved system to test their methods. Crystal-defect groups are cautioned that the approximations that successfully model single F-centers may fail for adjacent F-centers.

  7. Universal Features of Left-Right Entanglement Entropy.

    Science.gov (United States)

    Das, Diptarka; Datta, Shouvik

    2015-09-25

    We show the presence of universal features in the entanglement entropy of regularized boundary states for (1+1)D conformal field theories on a circle when the reduced density matrix is obtained by tracing over right- or left-moving modes. We derive a general formula for the left-right entanglement entropy in terms of the central charge and the modular S matrix of the theory. When the state is chosen to be an Ishibashi state, this measure of entanglement is shown to precisely reproduce the spatial entanglement entropy of a (2+1)D topological quantum field theory. We explicitly evaluate the left-right entanglement entropies for the Ising model, the tricritical Ising model and the su[over ^](2)_{k} Wess-Zumino-Witten model as examples.

  8. Perturbativity and mass scales of Left-Right Higgs bosons

    CERN Document Server

    Maiezza, Alessio; Nesti, Fabrizio

    2016-01-01

    The scalar sector of the minimal Left-Right model at TeV scale is revisited in light of the large quartic coupling needed for a heavy flavor-changing scalar. The stability and perturbativity of the effective potential is discussed and merged with constraints from low-energy processes. Thus the perturbative level of the Left-Right scale is sharpened. Lower limits on the triplet scalars are also derived: the left-handed triplet is bounded by oblique parameters, while the doubly-charged right-handed component is limited by the $h \\to \\gamma \\gamma, Z \\gamma$ decays. Current constraints disfavor their detection as long as $W_R$ is within the reach of the LHC.

  9. Simultaneous normal and parallel incidence planar left-handed metamaterial.

    Science.gov (United States)

    Lv, Jianhong; Yan, Baorong; Liu, Minghai; Hu, Xiwei

    2009-08-01

    We investigate numerically the negative refraction of a simultaneous normal and parallel incidence planar left-handed metamaterial (LHM) in this paper. This LHM is comprised of fourfold C-shaped rings, which are printed on both sides of the substrates symmetrically, and it can exhibit left-handed properties with electromagnetic wave incident in three different directions. The retrieved result and the simulated result verify the left-handed properties of the fourfold C-shaped metamaterial very well. Then the different electric responses of the normal and parallel incidence cases to the incident electromagnetic wave are discussed, and it is due to the different distribution of the induced currents in the metallic wires.

  10. Ischemic postconditioning attenuates liver warm ischemia-reperfusion injury through Akt-eNOS-NO-HIF pathway

    Directory of Open Access Journals (Sweden)

    Li Ping Y

    2011-10-01

    Full Text Available Abstract Background Ischemic postconditioning (IPO has been demonstrated to attenuate ischemia/reperfusion (I/R injury in the heart and brain, its roles to liver remain to be defined. The study was undertaken to determine if IPO would attenuate liver warm I/R injury and its protective mechanism. Methods Mice were divided into sham, I/R, IPO+I/R (occlusing the porta hepatis for 60 min, then treated for three cycles of 10 sec brief reperfusion consecutively, followed by a persistent reperfusion; L-NAME+ sham (L-NAME, 16 mg/kg, i.v., 5 min before repefusion; L-NAME+I/R; and L-NAME+ IPO. Blood flow of caudate and left lobe of the liver was blocked. Functional and morphologic changes of livers were evaluated. Contents of nitric oxide, eNOS and iNOS in serum were assayed. Concentration of eNOS, iNOS, malondialdehyde (MDA and activity of superoxide dismutase (SOD in hepatic tissue were also measured. Expressions of Akt, p-Akt and HIF-1α protein were determined by western blot. Expressions of TNF-α and ICAM-1 were measured by immunohistochemistry and RT-PCR. Results IPO attenuated the dramatically functional and morphological injuries. The levels of ALT was significantly reduced in IPO+I/R group (p Conclusions We found that IPO increased the content of NO and attenuated the overproduction of ROS and I/R-induced inflammation. Increased NO contents may contribute to increasing HIF-1α level, and HIF-1α and NO would simultaneously protect liver from I/R injury. These findings suggested IPO may have the therapeutic potential through Akt-eNOS-NO-HIF pathway for the better management of liver I/R injury.

  11. Transrectal ultrasonography of the left adrenal gland in healthy horses.

    Science.gov (United States)

    Durie, Inge; Van Loon, Gunther; Vermeire, Simon; De Clercq, Dominique; Vanschandevijl, Katleen; Deprez, Piet

    2010-01-01

    Little information is available on medical imaging of the adrenal glands in horses. We investigated the feasibility of transrectal ultrasonography to characterize the normal equine adrenal gland. Transrectal ultrasonography was performed in 25 healthy horses using a 7.5 MHz linear array probe at a displayed depth of 8 cm. Transrectal ultrasonography of the right adrenal gland was not feasible. For the left adrenal gland, the left kidney, the abdominal aorta, the left renal artery, the left renal vein, and the cranial mesenteric artery were used as landmarks. The size of the left adrenal gland was variable, but it generally appeared as a long, flat structure with a hyperechoic medulla surrounded by a hypoechoic cortex. The most cranial part of the gland could not be delineated appropriately in 11 horses (44%). The mean (+/-SD) thickness of the gland and medulla was 0.66 +/- 0.15cm (n = 25) and 0.28 +/- 0.09 cm (n = 25) near the caudal pole, 0.87 +/- 0.25 cm (n = 14) and 0.40 +/- 0.18 cm (n = 12) near the cranial pole, and 0.89 +/- 0.18 cm (n = 25) and 0.36 +/- 0.13 cm (n = 25) in the middle of the gland, respectively. The mean (+/-SD) length of the entire adrenal gland and of the medulla was 6.22 +/- 0.77 cm (n = 14) and 5.45 +/- 0.71 cm (n = 6), respectively. Transrectal ultrasonography allowed adequate visualization of the left adrenal gland in horses. PMID:20973389

  12. WAVE ATTENUATION OVER MUD BED: A PSEUDO-PLASTIC MODEL

    Institute of Scientific and Technical Information of China (English)

    Zhang Qing-he; Onyx W.H. Wai; Joseph H. W. Lee

    2003-01-01

    A two-layer model, with the upper layer being the perfect fluid and the lower layer being the pseudo-plastic fluid describing water wave attenuation over mud bed, was established. A simplified method based on the principle of equivalent work was applied to solve the boundary value problems. The computational results of the model show that the two-layer perfect fluid model and the perfect-viscous fluid model are all special cases of the present model. The complex nonlinear properties of wave attenuation over mud bed, can be explained by the present model, e.g., the wave dissipation rate decreases with the wave height in certain cases, while the small wave propagates over mud bed with less energy dissipation and large wave attenuates rapidly in other cases. Other factors influencing the wave attenuation were also discussed.

  13. Magnitude corrections for attenuation in the upper mantle

    International Nuclear Information System (INIS)

    Since 1969, a consistent discrepancy in seismic magnitudes of nuclear detonations at NTS compared with magnitudes of detonations elsewhere in the world has been observed. This discrepancy can be explained in terms of a relatively high seismic attenuation for compressional waves in the upper mantle beneath the NTS and in certain other locations. A correction has been developed for this attenuation based on a relationship between the velocity of compressional waves at the top of the earth's mantle (just beneath the Mohorovicic discontinuity) and the seismic attenuation further down in the upper mantle. Our new definition of body-wave magnitude includes corrections for attenuation in the upper mantle at both ends of the teleseismic body-wave path. These corrections bring the NTS oservations into line with measurements of foreign events, and enable one to make more reliable estimates of yields of underground nuclear explosions, wherever the explosion occurs

  14. Earth/Mars Landing Impact Attenuation Using Foam Project

    Data.gov (United States)

    National Aeronautics and Space Administration — On a previous ICA, a test correlated excel based software tool was developed using the innovative Stress?Energy method to better model impact attenuation using...

  15. Gamma ray attenuation coefficient measurement for neutron-absorbent materials

    Science.gov (United States)

    Jalali, Majid; Mohammadi, Ali

    2008-05-01

    The compounds Na 2B 4O 7, H 3BO 3, CdCl 2 and NaCl and their solutions attenuate gamma rays in addition to neutron absorption. These compounds are widely used in the shielding of neutron sources, reactor control and neutron converters. Mass attenuation coefficients of gamma related to the four compounds aforementioned, in energies 662, 778.9, 867.38, 964.1, 1085.9, 1173, 1212.9, 1299.1,1332 and 1408 keV, have been determined by the γ rays transmission method in a good geometry setup; also, these coefficients were calculated by MCNP code. A comparison between experiments, simulations and Xcom code has shown that the study has potential application for determining the attenuation coefficient of various compound materials. Experiment and computation show that H 3BO 3 with the lowest average Z has the highest gamma ray attenuation coefficient among the aforementioned compounds.

  16. Gamma ray attenuation coefficient measurement for neutron-absorbent materials

    International Nuclear Information System (INIS)

    The compounds Na2B4O7, H3BO3, CdCl2 and NaCl and their solutions attenuate gamma rays in addition to neutron absorption. These compounds are widely used in the shielding of neutron sources, reactor control and neutron converters. Mass attenuation coefficients of gamma related to the four compounds aforementioned, in energies 662, 778.9, 867.38, 964.1, 1085.9, 1173, 1212.9, 1299.1,1332 and 1408 keV, have been determined by the γ rays transmission method in a good geometry setup; also, these coefficients were calculated by MCNP code. A comparison between experiments, simulations and Xcom code has shown that the study has potential application for determining the attenuation coefficient of various compound materials. Experiment and computation show that H3BO3 with the lowest average Z has the highest gamma ray attenuation coefficient among the aforementioned compounds

  17. Dose reduction using a dynamic, piecewise-linear attenuator

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, Scott S., E-mail: sshsieh@stanford.edu [Department of Radiology, Stanford University, Stanford, California 94305 and Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States); Fleischmann, Dominik [Department of Radiology, Stanford University, Stanford, California 94305 (United States); Pelc, Norbert J. [Department of Radiology, Stanford University, Stanford, California 94305 and Department of Bioengineering, Stanford University, Stanford, California 94305 (United States)

    2014-02-15

    Purpose: The authors recently proposed a dynamic, prepatient x-ray attenuator capable of producing a piecewise-linear attenuation profile customized to each patient and viewing angle. This attenuator was intended to reduce scatter-to-primary ratio (SPR), dynamic range, and dose by redistributing flux. In this work the authors tested the ability of the attenuator to reduce dose and SPR in simulations. Methods: The authors selected four clinical applications, including routine full field-of-view scans of the thorax and abdomen, and targeted reconstruction tasks for an abdominal aortic aneurysm and the pancreas. Raw data were estimated by forward projection of the image volume datasets. The dynamic attenuator was controlled to reduce dose while maintaining peak variance by solving a convex optimization problem, assuminga priori knowledge of the patient anatomy. In targeted reconstruction tasks, the noise in specific regions was given increased weighting. A system with a standard attenuator (or “bowtie filter”) was used as a reference, and used either convex optimized tube current modulation (TCM) or a standard TCM heuristic. The noise of the scan was determined analytically while the dose was estimated using Monte Carlo simulations. Scatter was also estimated using Monte Carlo simulations. The sensitivity of the dynamic attenuator to patient centering was also examined by shifting the abdomen in 2 cm intervals. Results: Compared to a reference system with optimized TCM, use of the dynamic attenuator reduced dose by about 30% in routine scans and 50% in targeted scans. Compared to the TCM heuristics which are typically used withouta priori knowledge, the dose reduction is about 50% for routine scans. The dynamic attenuator gives the ability to redistribute noise and variance and produces more uniform noise profiles than systems with a conventional bowtie filter. The SPR was also modestly reduced by 10% in the thorax and 24% in the abdomen. Imaging with the dynamic

  18. Determination of left ventricular mass through SPECT imaging

    Science.gov (United States)

    Zárate-Morales, A.; Rodríguez-Villafuerte, M.; Martínez-Rodríguez, F.; Arévila-Ceballos, N.

    1998-08-01

    An edge detection algorithm has been applied to estimate left ventricular (LV) mass from single photon emission computed tomography (SPECT) thallium-201 images. The algorithm was validated using SPECT images of a phantom. The algorithm was applied to 20 patient studies from the Hospital de Cardiologia, Centro Médico Nacional Siglo XXI. Left ventricular masses derived from the stress and redistribution studies were highly correlated (r=0.96). The average LV masses obtained were 162±37 g and 169±34 g in the redistribution and stress studies, respectively.

  19. Flavor Changing Neutral Currents and Left-Right Symmetric model

    CERN Document Server

    Mansour, H M M

    2014-01-01

    In the present work we consider including the Flavor Changing Neutral Currents (FCNCs) in Left-Right Symmetric model. Within this model a simulation calculation are made of the decay width of Z' LR boson, the production cross section of the top quark and the top quark pair production cross section. The events were simulated according to the extension of Standard Model (SM) and the Left-Right symmetry Model (LRSM) based on the gauge symmetry group SU(3)C SU(2)L SU(2)R U(1)B-L. The LRSM model exhibits signatures of new physics Beyond the Standard Model (BSM) at the hadrons colliders.

  20. Matching models of left ventricle and systemic artery

    Institute of Scientific and Technical Information of China (English)

    柳兆荣; 吴驰

    1997-01-01

    To reveal how the matching models of the left ventricle and its afterload affect the pressure and flow in the aortic root, the differences between the measured pressure and flow waveforms and those determined by three kinds of matching model were compared. The results showed that, compared with the results by both matching models 1 and 2, the pressure and flow waveforms determined by matching model 3 established in this work were in the closest agreement with the corresponding experimental waveforms, therefore indicating that matching model 3 was a matching model that closely and rationally characterized the match between the left ventricle and the systemic artery.