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Sample records for attenuates load-induced left

  1. Trimetazidine protects against smoking-induced left ventricular remodeling via attenuating oxidative stress, apoptosis, and inflammation.

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    Xiang Zhou

    Full Text Available Trimetazidine, a piperazine derivative used as an anti-anginal agent, improves myocardial glucose utilization through inhibition of fatty acid metabolism. The present study was designed to investigate whether trimetazidine has the protective effects against smoking-induced left ventricular remodeling in rats. In this study, Wistar rats were randomly divided into 3 groups: smoking group (exposed to cigarette smoke, trimetazidine group (exposed to cigarette smoke and treated with trimetazidine, and control group. The echocardiographic and morphometric data indicated that trimetazidine has protective effects against smoking-induced left ventricular remodeling. Oxidative stress was evaluated by detecting malondialdehyde, superoxide dismutase, and glutathione peroxidase in the supernatant of left ventricular tissue. Cardiomyocyte apoptotic rate was determined by flow cytometry with Annexin V/PI staining. Gene expression and serum levels of inflammatory markers, including interleukin-1β, interleukin-6, and tumor necrosis factor-α, were deteced by quantitative real-time PCR and enzyme-linked immunosorbent assay. Our results suggested that trimetazidine could significantly reduce smoking-induced oxidative stress, apoptosis, and inflammation. In conclusion, our study demonstrates that trimetazidine protects against smoking-induced left ventricular remodeling via attenuating oxidative stress, apoptosis, and inflammation.

  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. Krill oil attenuates left ventricular dilatation after myocardial infarction in rats

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    Fosshaug Linn E

    2011-12-01

    Full Text Available Abstract Background In the western world, heart failure (HF is one of the most important causes of cardiovascular mortality. Supplement with n-3 polyunsaturated fatty acids (PUFA has been shown to improve cardiac function in HF and to decrease mortality after myocardial infarction (MI. The molecular structure and composition of n-3 PUFA varies between different marine sources and this may be of importance for their biological effects. Krill oil, unlike fish oil supplements, contains the major part of the n-3 PUFA in the form of phospholipids. This study investigated effects of krill oil on cardiac remodeling after experimental MI. Rats were randomised to pre-treatment with krill oil or control feed 14 days before induction of MI. Seven days post-MI, the rats were examined with echocardiography and rats in the control group were further randomised to continued control feed or krill oil feed for 7 weeks before re-examination with echocardiography and euthanization. Results The echocardiographic evaluation showed significant attenuation of LV dilatation in the group pretreated with krill oil compared to controls. Attenuated heart weight, lung weight, and levels of mRNA encoding classical markers of LV stress, matrix remodeling and inflammation reflected these findings. The total composition of fatty acids were examined in the left ventricular (LV tissue and all rats treated with krill oil showed a significantly higher proportion of n-3 PUFA in the LV tissue, although no difference was seen between the two krill oil groups. Conclusions Supplement with krill oil leads to a proportional increase of n-3 PUFA in myocardial tissue and supplement given before induction of MI attenuates LV remodeling.

  4. Berberine attenuates adverse left ventricular remodeling and cardiac dysfunction after acute myocardial infarction in rats: role of autophagy.

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    Zhang, Yao-Jun; Yang, Shao-Hua; Li, Ming-Hui; Iqbal, Javaid; Bourantas, Christos V; Mi, Qiong-Yu; Yu, Yi-Hui; Li, Jing-Jing; Zhao, Shu-Li; Tian, Nai-Liang; Chen, Shao-Liang

    2014-12-01

    The present study aimed to test the hypothesis that berberine, a plant-derived anti-oxidant, attenuates adverse left ventricular remodelling and improves cardiac function in a rat model of myocardial infarction (MI). Furthermore, the potential mechanisms that mediated the cardioprotective actions of berberine, in particular the effect on autophagy, were also investigated. Acute MI was induced by ligating the left anterior descending coronary artery of Sprague-Dawley rats. Cardiac function was assessed by transthoracic echocardiography. The protein activity/levels of autophagy related to signalling pathways (e.g. LC-3B, Beclin-1) were measured in myocardial tissue by immunohistochemical staining and western blot. Four weeks after MI, berberine significantly prevented cardiac dysfunction and adverse cardiac remodelling. MI rats treated with low dose berberine (10 mg/kg per day) showed higher left ventricular ejection fraction and fractional shortening than those treated with high-dose berberine (50 mg/kg per day). Both doses reduced interstitial fibrosis and post-MI adverse cardiac remodelling. The cardioprotective action of berberine was associated with increased LC-3B II and Beclin-1 expressions. Furthermore, cardioprotection with berberine was potentially related to p38 MAPK inhibition and phospho-Akt activation. The present in vivo study showed that berberine is effective in promoting autophagy, and subsequently attenuating left ventricular remodelling and cardiac dysfunction after MI. The potential underlying mechanism is augmentation of autophagy through inhibition of p38 MAPK and activation of phospho-Akt signalling pathways.

  5. Connective tissue growth factor inhibition attenuates left ventricular remodeling and dysfunction in pressure overload-induced heart failure.

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    Szabó, Zoltán; Magga, Johanna; Alakoski, Tarja; Ulvila, Johanna; Piuhola, Jarkko; Vainio, Laura; Kivirikko, Kari I; Vuolteenaho, Olli; Ruskoaho, Heikki; Lipson, Kenneth E; Signore, Pierre; Kerkelä, Risto

    2014-06-01

    Connective tissue growth factor (CTGF) is involved in the pathogenesis of various fibrotic disorders. However, its role in the heart is not clear. To investigate the role of CTGF in regulating the development of cardiac fibrosis and heart failure, we subjected mice to thoracic aortic constriction (TAC) or angiotensin II infusion, and antagonized the function of CTGF with CTGF monoclonal antibody (mAb). After 8 weeks of TAC, mice treated with CTGF mAb had significantly better preserved left ventricular (LV) systolic function and reduced LV dilatation compared with mice treated with control immunoglobulin G. CTGF mAb-treated mice exhibited significantly smaller cardiomyocyte cross-sectional area and reduced expression of hypertrophic marker genes. CTGF mAb treatment reduced the TAC-induced production of collagen 1 but did not significantly attenuate TAC-induced accumulation of interstitial fibrosis. Analysis of genes regulating extracellular matrix proteolysis showed decreased expression of plasminogen activator inhibitor-1 and matrix metalloproteinase-2 in mice treated with CTGF mAb. In contrast to TAC, antagonizing the function of CTGF had no effect on LV dysfunction or LV hypertrophy in mice subjected to 4-week angiotensin II infusion. Further analysis showed that angiotensin II-induced expression of hypertrophic marker genes or collagens was not affected by treatment with CTGF mAb. In conclusion, CTGF mAb protects from adverse LV remodeling and LV dysfunction in hearts subjected to pressure overload by TAC. Antagonizing the function of CTGF may offer protection from cardiac end-organ damage in patients with hypertension.

  6. 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.

  7. Rescuing loading induced bone formation at senescence.

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    Sundar Srinivasan

    Full Text Available The increasing incidence of osteoporosis worldwide requires anabolic treatments that are safe, effective, and, critically, inexpensive given the prevailing overburdened health care systems. While vigorous skeletal loading is anabolic and holds promise, deficits in mechanotransduction accrued with age markedly diminish the efficacy of readily complied, exercise-based strategies to combat osteoporosis in the elderly. Our approach to explore and counteract these age-related deficits was guided by cellular signaling patterns across hierarchical scales and by the insight that cell responses initiated during transient, rare events hold potential to exert high-fidelity control over temporally and spatially distant tissue adaptation. Here, we present an agent-based model of real-time Ca(2+/NFAT signaling amongst bone cells that fully described periosteal bone formation induced by a wide variety of loading stimuli in young and aged animals. The model predicted age-related pathway alterations underlying the diminished bone formation at senescence, and hence identified critical deficits that were promising targets for therapy. Based upon model predictions, we implemented an in vivo intervention and show for the first time that supplementing mechanical stimuli with low-dose Cyclosporin A can completely rescue loading induced bone formation in the senescent skeleton. These pre-clinical data provide the rationale to consider this approved pharmaceutical alongside mild physical exercise as an inexpensive, yet potent therapy to augment bone mass in the elderly. Our analyses suggested that real-time cellular signaling strongly influences downstream bone adaptation to mechanical stimuli, and quantification of these otherwise inaccessible, transient events in silico yielded a novel intervention with clinical potential.

  8. 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.

  9. 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.

  10. 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.

  11. The molecular basis for load-induced skeletal muscle hypertrophy.

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    Marcotte, George R; West, Daniel W D; Baar, Keith

    2015-03-01

    In a mature (weight neutral) animal, an increase in muscle mass only occurs when the muscle is loaded sufficiently to cause an increase in myofibrillar protein balance. A tight relationship between muscle hypertrophy, acute increases in protein balance, and the activity of the mechanistic target of rapamycin complex 1 (mTORC1) was demonstrated 15 years ago. Since then, our understanding of the signals that regulate load-induced hypertrophy has evolved considerably. For example, we now know that mechanical load activates mTORC1 in the same way as growth factors, by moving TSC2 (a primary inhibitor of mTORC1) away from its target (the mTORC activator) Rheb. However, the kinase that phosphorylates and moves TSC2 is different in the two processes. Similarly, we have learned that a distinct pathway exists whereby amino acids activate mTORC1 by moving it to Rheb. While mTORC1 remains at the forefront of load-induced hypertrophy, the importance of other pathways that regulate muscle mass are becoming clearer. Myostatin, is best known for its control of developmental muscle size. However, new mechanisms to explain how loading regulates this process are suggesting that it could play an important role in hypertrophic muscle growth as well. Last, new mechanisms are highlighted for how β2 receptor agonists could be involved in load-induced muscle growth and why these agents are being developed as non-exercise-based therapies for muscle atrophy. Overall, the results highlight how studying the mechanism of load-induced skeletal muscle mass is leading the development of pharmaceutical interventions to promote muscle growth in those unwilling or unable to perform resistance exercise.

  12. 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.

  13. Recovery of the Frank-Starling mechanism by coenzyme Q10 in patients with load-induced contractility depression.

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    Oda, T

    1993-01-01

    Load-induced contractility depression, in which supernormal left ventricular ejection fraction and contractility at rest decrease by added afterload, is most often found in children with mitral valve prolapse who have symptoms. Patients have high ventricular end-diastolic pressure at rest, which is further increased by afterload challenge. The Frank-Starling mechanism may be maximally mobilized with high preload even at rest to compensate for the intrinsically depressed inotropic state. Therefore, preload reserve may be easily exhausted due to afterload addition. We aimed to determine left ventricular end-diastolic fiber length, stroke work, and contractility before and during handgrip by echocardiograms to obtain evidence for the Frank-Starling mechanism in patients and controls, including patients treated with coenzyme Q10. The subjects were divided into four groups, each consisting of 30 children aged 6-16 years: group 1, normals; group 2, patients; group 3, the same patients as in group 2 after coenzyme Q10 therapy; and group 4, patients with asymptomatic mitral valve prolapse. Baseline values and percentage increases in systolic blood pressure, heart rate, and left ventricular wall stress showed no differences among the groups. Only in group 2 were the percentage increase in ejection fraction, fiber shortening velocity, contractility, and end-diastolic dimension strongly negative, despite supernormal baseline levels. In other groups, these were significantly positive, without intergroup differences. We conclude that in the heart with load-induced contractility depression, the Frank-Starling mechanism deviates from normal. The normal Frank-Starling mechanism was recovered due to coenzyme Q10, which may improve disturbed bioenergetic function at the molecular level.

  14. 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...

  15. Load-induced error identification of hydrostatic turntable and its influence on machining accuracy

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    程强; 任伟达; 刘志峰; 陈东菊; 顾佩华

    2016-01-01

    In heavy duty machine tools, hydrostatic turntable is often used as a means for providing rotational motion and supporting workpiece, so the accuracy of turntable is crucial for part machining. In order to analyze the influence of load-indcued errors on machining accuracy, an identification model of load-induced errors based on the deformation caused by applied load of hydrostatic turntable of computerized numerical control (CNC) gantry milling heavy machine is proposed. Based on multi-body system theory and screw theory, the space machining accuracy model of heavy duty machine tool is established with consideration of identified load-induced errors. And then, the influence of load-induced errors on space machining accuracy and the roundness error of a milled hole is analyzed. The analysis results show that load-induced errors have a big influence on the roundness error of machined hole, especially when the center of the milled hole is far from that of hydrostatic turntable.

  16. The influence of nodes sequence and extraneous load induced by graphical overviews on hypertext learning

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    Bezdan, Eniko; Kester, Liesbeth; Kirschner, Paul A.

    2013-01-01

    Bezdan, E., Kester, L., & Kirschner, P. A. (2013). The influence of nodes sequence and extraneous load induced by graphical overviews on hypertext learning. Computers in Human Behavior, 29(3), 870-880.

  17. Regulation of PTEN/Akt pathway enhances cardiomyogenesis and attenuates adverse left ventricular remodeling following thymosin β4 Overexpressing embryonic stem cell transplantation in the infarcted heart.

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    Binbin Yan

    Full Text Available Thymosin β4 (Tβ4, a small G-actin sequestering peptide, mediates cell proliferation, migration, and angiogenesis. Whether embryonic stem (ES cells, overexpressing Tβ4, readily differentiate into cardiac myocytes in vitro and in vivo and enhance cardioprotection following transplantation post myocardial infarction (MI remains unknown. Accordingly, we established stable mouse ES cell lines, RFP-ESCs and Tβ4-ESCs, expressing RFP and an RFP-Tβ4 fusion protein, respectively. In vitro, the number of spontaneously beating embryoid bodies (EBs was significantly increased in Tβ4-ESCs at day 9, 12 and 15, compared with RFP-ESCs. Enhanced expression of cardiac transcriptional factors GATA-4, Mef2c and Txb6 in Tβ4-EBs, as confirmed with real time-PCR analysis, was accompanied by the increased number of EB areas stained positive for sarcomeric α-actin in Tβ4-EBs, compared with the RFP control, suggesting a significant increase in functional cardiac myocytes. Furthermore, we transplanted Tβ4-ESCs into the infarcted mouse heart and performed morphological and functional analysis 2 weeks after MI. There was a significant increase in newly formed cardiac myocytes associated with the Notch pathway, a decrease in apoptotic nuclei mediated by an increase in Akt and a decrease in levels of PTEN. Cardiac fibrosis was significantly reduced, and left ventricular function was significantly augmented in the Tβ4-ESC transplanted group, compared with controls. It is concluded that genetically modified Tβ4-ESCs, potentiates their ability to turn into cardiac myocytes in vitro as well as in vivo. Moreover, we also demonstrate that there was a significant decrease in both cardiac apoptosis and fibrosis, thus improving cardiac function in the infarcted heart.

  18. Flax lignan concentrate attenuate hypertension and abnormal left ventricular contractility via modulation of endogenous biomarkers in two-kidney-one-clip (2K1C hypertensive rats

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    Sameer Hanmantrao Sawant

    Full Text Available ABSTRACT The present investigation was designed to study the effect of flax lignan concentrate obtained from Linum usitatissimum L., Linaceae, in two-kidney, one clip (2K1C hypertension model in Wistar rats. 2K1C Goldblatt model rats were divided randomly into six groups: sham, 2K1C control, captopril (30 mg/kg, flax lignan concentrate (200, 400 and 800 mg/kg. Flax lignan concentrate and captopril were administered daily for eight consecutive weeks. Sham-operated, and 2K1C control rats received the vehicle. Treatment with flax lignan concentrate (400 and 800 mg/kg significantly and dose-dependently restored the hemodynamic parameters systolic blood pressure, diastolic blood pressure, mean arterial blood pressure and left ventricular functions. The flax lignan concentrate significantly restored the elevated hepatic, renal and cardiac marker enzymes in the serum. It also restored the organs weights (kidney and heart, serum electrolyte level and histological abnormalities. Furthermore, flax lignan concentrate significantly elevated the level of biochemical markers that is enzymatic antioxidants superoxide dismutase, glutathione and decreased malondialdehyde in the heart and kidney tissues. Meanwhile, we found that plasma nitric oxide and plasma nitric oxide synthase contents were significantly increased in the flax lignan concentrate-treated group, and plasma endothelin-1 and renal angiotensin-II levels were significantly lower than 2K1C hypertensive group. In conclusion, the antihypertensive and antioxidant effect of flax lignan concentrate were dose-dependent and at the highest dose (i.e. 800 mg/kg similar to those of captopril (30 mg/kg. It is suggested that flax lignan concentrate reduced blood pressure by reduction of renal angiotensin-II level, inhibition of plasma endothelin-1 production, induction of the nitric oxide, nitric oxide synthase and in vivo antioxidant defense system.

  19. 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

  20. 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.

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

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    Koya, Tomoyuki; Nishizawa, Sono; Ohno, Yoshitaka; Goto, Ayumi; Ikuta, Akihiro; Suzuki, Miho; Ohira, Tomotaka; Egawa, Tatsuro; Nakai, Akira; Sugiura, Takao; Ohira, Yoshinobu; Yoshioka, Toshitada; Beppu, Moroe; Goto, Katsumasa

    2013-01-01

    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 (pmuscle 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.

  2. ARE LEFT HANDED SURGEONS LEFT OUT?

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    SriKamkshi Kothandaraman; Balasubramanian Thiagarajan

    2012-01-01

    Being a left-handed surgeon, more specifically a left-handed ENT surgeon, presents a unique pattern of difficulties.This article is an overview of left-handedness and a personal account of the specific difficulties a left-handed ENT surgeon faces.

  3. Hypoplastic left heart syndrome

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    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 ...

  4. 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.

  5. Chronic administration of angiotensin-(1-7) attenuates pressure-overload left ventricular hypertrophy and fibrosis in rats%血管紧张素-(1-7)对腹主动脉缩窄大鼠心肌肥厚和纤维化的影响

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    王立军; 何建桂; 马虹; 蔡乙明; 廖新学; 曾武涛; 柳俊; 王礼春

    2005-01-01

    Background To test the hypothesis that chronic administration of angiotensin-(1-7) [Ang-(1-7)] attenuates cardiac hypertrophy in rats in vivo. Methods Coarctation of the suprarenal abdominal aorta was performed in 41 8-week-old male Sprague Dawley rats. Twenty-four hours after the operation, osmotic minipumps were surgically implanted subcutaneously in the rats, which were randomly divided into 3 groups, including a sham-operation group (n=15) receiving infusion with normal saline, a suprarenal aortic coarctation group (n=12), and a suprarenal aortic coarctation group (n=14) with Ang-(1-7) treatment at the dose of 25 μg.kg-1 .h-1. Four weeks later, the systolic and diastolic blood pressures were measured and the left ventricular mass index (LVMI, mg/g) was calculated from the ratio of left ventricular weight to body weight. The concentrations of Ang Ⅱ in the plasma and myocardium were measured by radioimmunoassay, and myocardial interstitial collagen volume fraction (ICVF) was determined by quantitative morphometry of the sections with Picrosirius red staining using an automated image analyzer. Results Suprarenal abdominal aortic coarctation induced a significant increase in carotid artery systolic and diastolic blood pressure, heart weight, LVMI, ICVF, and the concentration of Ang Ⅱ in the myocardium (P<0.01). Chronic administration of Ang-(1-7) attenuated the increase in the heart weight, LVMI, ICVF and left ventricular diastolic end pressure (LVEDP) caused by suprarenal abdominal aortic coarctation (P<0.05). Ang-(1-7) also increased the formerly decreased maximum left ventricular pressure reduction rate (-dP/dtmax) (P<0.05), but had no effect on blood pressure and the concentration of Ang Ⅱ in the myocardium. No difference was noted in plasma concentration of Ang Ⅱ between the 3 groups. Conclusions Ang-(1-7) attenuates cardiac hypertrophy and fibrosis and preserved the impaired left ventricular function induced by left ventricular pressure

  6. Left Ventricular Hypertrophy

    Science.gov (United States)

    ... of left ventricular hypertrophy in hypertension. http://www.uptodate.com/home. Accessed April 6, 2015. Podrid PJ. Left ventricular hypertrophy and arrhythmia. http://www.uptodate.com/home. Accessed April 6, 2015. Chatterjee S, et ...

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

    Directory of Open Access Journals (Sweden)

    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.

  8. 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.

  9. 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.

  10. 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....

  11. 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

  12. Tracer attenuation in groundwater

    Science.gov (United States)

    Cvetkovic, Vladimir

    2011-12-01

    The self-purifying capacity of aquifers strongly depends on the attenuation of waterborne contaminants, i.e., irreversible loss of contaminant mass on a given scale as a result of coupled transport and transformation processes. A general formulation of tracer attenuation in groundwater is presented. Basic sensitivities of attenuation to macrodispersion and retention are illustrated for a few typical retention mechanisms. Tracer recovery is suggested as an experimental proxy for attenuation. Unique experimental data of tracer recovery in crystalline rock compare favorably with the theoretical model that is based on diffusion-controlled retention. Non-Fickian hydrodynamic transport has potentially a large impact on field-scale attenuation of dissolved contaminants.

  13. Left heart catheterization

    Science.gov (United States)

    Catheterization - left heart ... to help guide the catheters up into your heart and arteries. Dye will be injected into your ... in the blood vessels that lead to your heart. The catheter is then moved through the aortic ...

  14. 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)

  15. Load induced blindness

    OpenAIRE

    Macdonald, J. S. P.; Lavie, N.

    2008-01-01

    Although the perceptual load theory of attention has stimulated a great deal of research, evidence for the role of perceptual load in determining perception has typically relied oil indirect measures that infer perception from distractor effects on reaction times or neural activity (see N. Lavie, 2005. for a review). Here we varied the level of perceptual load in a letter-search task and assessed its effect oil the conscious perception of a search-irrelevant shape stimulus appearing in the pe...

  16. Load Induced Blindness

    Science.gov (United States)

    Macdonald, James S. P.; Lavie, Nilli

    2008-01-01

    Although the perceptual load theory of attention has stimulated a great deal of research, evidence for the role of perceptual load in determining perception has typically relied on indirect measures that infer perception from distractor effects on reaction times or neural activity (see N. Lavie, 2005, for a review). Here we varied the level of…

  17. 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 ...

  18. 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...

  19. 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.

  20. 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,

  1. 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.

  2. 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

  3. Left musculus sternalis.

    Science.gov (United States)

    Arráez-Aybar, L A; Sobrado-Perez, J; Merida-Velasco, J R

    2003-07-01

    During routine dissection in the Morphological Sciences Department II of the Universidad Complutense de Madrid, the presence of a sternalis muscle was observed in the left hemithorax of a 70-year-old male cadaver. We report on its position, relationships, and innervation, as well as its clinical relevance, indicating some guidelines for its physical examination. We also present a brief overview of the existing literature regarding the nomenclature, historical reports, and incidence of this muscle.

  4. 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.

  5. 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.

  6. 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.

  7. Your left-handed brain

    OpenAIRE

    2014-01-01

    While most people prefer to use their right hand to brush their teeth, throw a ball, or hold a tennis racket, left-handers prefer to use their left hand. This is the case for around 10% of all people. There was a time (not so long ago) when left-handers were stigmatized (see Glossary) in Western (and other) communities: it was considered a bad sign if you were left-handed, and left-handed children were often forced to write with their right hand. This is nonsensical: there is nothing wrong wi...

  8. 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.

  9. Left ventricular apical diseases.

    Science.gov (United States)

    Cisneros, Silvia; Duarte, Ricardo; Fernandez-Perez, Gabriel C; Castellon, Daniel; Calatayud, Julia; Lecumberri, Iñigo; Larrazabal, Eneritz; Ruiz, Berta Irene

    2011-08-01

    There are many disorders that may involve the left ventricular (LV) apex; however, they are sometimes difficult to differentiate. In this setting cardiac imaging methods can provide the clue to obtaining the diagnosis. The purpose of this review is to illustrate the spectrum of diseases that most frequently affect the apex of the LV including Tako-Tsubo cardiomyopathy, LV aneurysms and pseudoaneurysms, apical diverticula, apical ventricular remodelling, apical hypertrophic cardiomyopathy, LV non-compaction, arrhythmogenic right ventricular dysplasia with LV involvement and LV false tendons, with an emphasis on the diagnostic criteria and imaging features. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s13244-011-0091-6) contains supplementary material, which is available to authorized users.

  10. 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.

  11. 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.

  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.

  13. Retroaortic left renal vein joining the left common iliac vein

    Energy Technology Data Exchange (ETDEWEB)

    Brancatelli, G.; Galia, M.; Finazzo, M.; Sparacia, G.; Pardo, S.; Lagalla, R. [Dept. of Radiology ' ' P. Cignolini' ' , Univ. of Palermo (Italy)

    2000-11-01

    Retroaortic left renal vein joining the left common iliac vein is a rare congenital anomaly in the development of the inferior vena cava. To our knowledge, only one case has been reported in the literature; however, its imaging features have never been described. A 27-year-old male presented with a 1-year history of recurrent right flank pain, dysuria, hematuria, and fever (39 C). Computed tomography and MR venography showed a retroaortic left renal vein joining the left common iliac vein. We present the CT and MR venography findings and discuss their feasibility in showing this congenital anomaly. (orig.)

  14. 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.

  15. Two-Dimensional Simulation of Left-Handed Metamaterial Flat Lens Using Remcon XFDTD

    Science.gov (United States)

    Wilson, Jeffrey D.; Reinert, Jason M.

    2006-01-01

    Remcom's XFDTD software was used to model the properties of a two-dimensional left-handed metamaterial (LHM) flat lens. The focusing capability and attenuation of the material were examined. The results showed strong agreement with experimental results and theoretical predictions of focusing effects and focal length. The inherent attenuation in the model corresponds well with the experimental results and implies that the code does a reasonably accurate job of modeling the actual metamaterial.

  16. 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.

  17. 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…

  18. 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....

  19. 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. .

  20. Left ventricular wall stress compendium.

    Science.gov (United States)

    Zhong, L; Ghista, D N; Tan, R S

    2012-01-01

    Left ventricular (LV) wall stress has intrigued scientists and cardiologists since the time of Lame and Laplace in 1800s. The left ventricle is an intriguing organ structure, whose intrinsic design enables it to fill and contract. The development of wall stress is intriguing to cardiologists and biomedical engineers. The role of left ventricle wall stress in cardiac perfusion and pumping as well as in cardiac pathophysiology is a relatively unexplored phenomenon. But even for us to assess this role, we first need accurate determination of in vivo wall stress. However, at this point, 150 years after Lame estimated left ventricle wall stress using the elasticity theory, we are still in the exploratory stage of (i) developing left ventricle models that properly represent left ventricle anatomy and physiology and (ii) obtaining data on left ventricle dynamics. In this paper, we are responding to the need for a comprehensive survey of left ventricle wall stress models, their mechanics, stress computation and results. We have provided herein a compendium of major type of wall stress models: thin-wall models based on the Laplace law, thick-wall shell models, elasticity theory model, thick-wall large deformation models and finite element models. We have compared the mean stress values of these models as well as the variation of stress across the wall. All of the thin-wall and thick-wall shell models are based on idealised ellipsoidal and spherical geometries. However, the elasticity model's shape can vary through the cycle, to simulate the more ellipsoidal shape of the left ventricle in the systolic phase. The finite element models have more representative geometries, but are generally based on animal data, which limits their medical relevance. This paper can enable readers to obtain a comprehensive perspective of left ventricle wall stress models, of how to employ them to determine wall stresses, and be cognizant of the assumptions involved in the use of specific models.

  1. Ultrasonic attenuation in pearlitic steel.

    Science.gov (United States)

    Du, Hualong; Turner, Joseph A

    2014-03-01

    Expressions for the attenuation coefficients of longitudinal and transverse ultrasonic waves are developed for steel with pearlitic microstructure. This type of lamellar duplex microstructure influences attenuation because of the lamellar spacing. In addition, longitudinal attenuation measurements were conducted using an unfocused transducer with 10 MHz central frequency on the cross section of a quenched railroad wheel sample. The dependence of longitudinal attenuation on the pearlite microstructure is observed from the changes of longitudinal attenuation from the quenched tread surface to deeper locations. The results show that the attenuation value is lowest and relatively constant within the quench depth, then increases linearly. The experimental results demonstrate a reasonable agreement with results from the theoretical model. Ultrasonic attenuation provides an important non-destructive method to evaluate duplex microstructure within grains which can be implemented for quality control in conjunction with other manufacturing processes.

  2. Metoprolol treatment lowers thrombospondin-4 expression in rats with myocardial infarction and left ventricular hypertrophy.

    Science.gov (United States)

    Mustonen, Erja; Leskinen, Hanna; Aro, Jani; Luodonpää, Marja; Vuolteenaho, Olli; Ruskoaho, Heikki; Rysä, Jaana

    2010-09-01

    Thrombospondins are matrix proteins linked to extracellular matrix remodelling but their precise role in the heart is not known. In this study, we characterised left ventricular thrombospondin-1 and -4 expression in rats treated with a beta-blocker metoprolol during the remodelling process in response to pressure overload and acute myocardial infarction. Left ventricular thrombospondin-1 and thrombospondin-4 mRNA levels increased 8.4-fold (p infarction, respectively. Metoprolol infusion by osmotic minipumps (1.5 mg/kg/hr) for 2 weeks after myocardial infarction decreased thrombospondin-1 and thrombospondin-4 mRNA levels (55% and 50%, respectively), improved left ventricular function, and attenuated left ventricular remodelling with reduction of left ventricular atrial natriuretic peptide and brain natriuretic peptide gene expression. Thrombospondin-1 and -4 mRNA levels correlated positively with echocardiographic parameters of left ventricular remodelling as well as with atrial natriuretic peptide and brain natriuretic peptide gene expression. Moreover, there was a negative correlation between left ventricular ejection fraction and thrombospondin-1 mRNA levels. In 12-month-old spontaneously hypertensive rats with left ventricular hypertrophy, metoprolol decreased left ventricular thrombospondin-4 levels and attenuated remodelling while thrombospondin-1, atrial natriuretic peptide and brain natriuretic peptide mRNA levels as well as left ventricular function remained unchanged. In metoprolol-treated spontaneously hypertensive rats, thrombospondin-4 gene expression correlated with parameters of left ventricular remodelling, while no correlations between thrombospondins and natriuretic peptides were observed. These results indicate that thrombospondin-1 expression is linked exclusively to left ventricular remodelling process post-infarction while thrombospondin-4 associates with myocardial remodelling both after myocardial infarction and in hypertensive heart disease

  3. 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...

  4. 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.

  5. [Left pulmonary agenesis diagnosed late].

    Science.gov (United States)

    Deleanu, Oana; Pătraşcu, Natalia; Nebunoiu, Ana-Maria; Vintilă, V; Ulmeanu, Ruxandra; Mihălţan, F D

    2010-01-01

    We present the case of a 51 years old female-patient, with severe dextroscoliosis, having like unique symptom progressive dyspnea. The blood samples reveals polycythemia, the radiological exam shows the opacification of 2/3 of the left thorax, the absence of the lung structure in the other 1/3, the deviation of the mediastinum, and dextroscoliosis; the computed tomography reveals the absence of the left lung artery and the left airways, compensatory hyperinflation of the right lung and dilatation of the trunk and right pulmonary artery; the bronchoscopy does not visualize the carina or the left main bronchus, typical for pulmonary agenesis. Echocardiography confirmed the absence of left pulmonary artery and shows mild pulmonary hypertension (systolic pressure in the pulmonary artery of 33 mmHg) with dilatation of the right cavities, but good cinetics. We face a case of pulmonary agenesis lately diagnosed, with modest functional cardiologic implications, limited therapeutic options and good survival, justified by the late appearance of the pulmonary hypertension of low severity and without worsening in time.

  6. Pentoxifylline Attenuates Cardiac Remodeling Induced by Tobacco Smoke Exposure

    Energy Technology Data Exchange (ETDEWEB)

    Minicucci, Marcos; Oliveira, Fernando; Santos, Priscila; Polegato, Bertha; Roscani, Meliza; Fernandes, Ana Angelica; Lustosa, Beatriz; Paiva, Sergio; Zornoff, Leonardo; Azevedo, Paula, E-mail: paulasa@fmb.unesp.br [Faculdade de Medicina de Botucatu, Universidade Estadual Paulista, São Paulo, SP (Brazil)

    2016-05-15

    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. The present study tested the hypothesis that pentoxifylline would attenuate cardiac remodeling induced by smoking. 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%. 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. 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.

  7. Producing The New Regressive Left

    DEFF Research Database (Denmark)

    Crone, Christine

    to be a committed artist, and how that translates into supporting al-Assad’s rule in Syria; the Ramadan programme Harrir Aqlak’s attempt to relaunch an intellectual renaissance and to promote religious pluralism; and finally, al-Mayadeen’s cooperation with the pan-Latin American TV station TeleSur and its ambitions...... becomes clear from the analytical chapters is the emergence of the new cross-ideological alliance of The New Regressive Left. This emerging coalition between Shia Muslims, religious minorities, parts of the Arab Left, secular cultural producers, and the remnants of the political,strategic resistance...... coalition (Iran, Hizbollah, Syria), capitalises on a series of factors that bring them together in spite of their otherwise diverse worldviews and agendas. The New Regressive Left is united by resistance against the growing influence of Saudi Arabia in the religious, cultural, political, economic...

  8. CD147/MMP-9通路上调改善自发性高血压大鼠早期心室重构%Upregulation of CD147/MMP-9 pathway attenuates early left ventricular remodeling in rats with spontaneous hypertension

    Institute of Scientific and Technical Information of China (English)

    周万兴; 李博维; 杨小蓉; 周玉良; 谭永锦; 袁丛聪; 宋玉兰; 陈骁; 张卫

    2015-01-01

    目的:探讨CD147/MMP-9通路对自发性高血压大鼠(SHR)早期心室重构的影响。方法:8周龄雄性 SHR 随机分成 SHR、CD147和 CD147+ DOX 组(n =10/组),8周龄雄性 WKY 大鼠为对照组(WKY组,n =10)。 CD147及CD147+ DOX 组予人重组CD147(600 ng/kg 1.5 mL)、SHR 及WKY 组予等量生理盐水,静注,每周1次。 CD147+ DOX组加多西环素(DOX,30 mg/kg,1.5 mL),其他组加生理盐水灌胃每天1次。第56天超声心动图检查、测左心室重量指数(LVWI)、切片(HE、VG染色)观察心肌细胞和胶原增殖、western blot 测心肌 MMP-9、TIMP-1、CD147、Ⅰ和Ⅲ型胶原水平。结果:与 WKY 组比,SHR 组心肌 CD147、MMP-9、MMP-9/TIMP-1明显低(P <0.05);心肌细胞肥大、部分纤维断裂、胞浆溶解坏死,胶原容积分数(CVF)Ⅰ、Ⅲ型胶原显著增高(P <0.05)。而与SHR 组比,CD147组CD147、MMP-9、MMP-9/TIMP-1明显增高,心肌细胞形态和排列改善,LVWI、CVF、Ⅰ、Ⅲ型胶原明显降低。但CD147+DOX 组尽管CD147、MMP-9、MMP-9/TIMP-1比CD147组无明显降低,CVF与Ⅰ、Ⅲ型胶原却明显增高,心肌细胞肥大及纤维断裂现象再次出现。结论:SHR早期心室重构可能与CD147/MMP-9通路受抑制有关,输入CD147上调该通路可以改善该心室重构。%Objective To investigate the effects of CD147/MMP-9 pathway on early left ventricular remodeling Methods 30 healthy eight-week male SHR were divided into 3 groups (n = 10 for each group). SHR group received tail vein injections of normal saline weekly; CD147 group received CD147 of 600 ng·kg-1 weekly; and CD147+DOX group received CD147 of 600 ng/kg weekly and intragastric administration of DOX ( doxycycline ) of 30 mg/kg daily . 10 healthy eight-week male Wistar-Kyoto rats (WKY group) were treated as SHR group. Echocardiography, myocardial sections microscopy examination (HE and VG

  9. 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

  10. 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.

  11. 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.

  12. 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.

  13. AVE 0991 attenuates cardiac hypertrophy through reducing oxidative stress.

    Science.gov (United States)

    Ma, Yuedong; Huang, Huiling; Jiang, Jingzhou; Wu, Lingling; Lin, Chunxi; Tang, Anli; Dai, Gang; He, Jiangui; Chen, Yili

    2016-06-10

    AVE 0991, the nonpeptide angiotensin-(1-7) (Ang-(1-7)) analog, is recognized as having beneficial cardiovascular effects. However, the mechanisms have not been fully elucidated. This study was designed to investigate the effects of AVE 0991 on cardiac hypertrophy and the mechanisms involved. Mice were underwent aortic banding to induce cardiac hypertrophy followed by the administration of AVE 0991 (20 mg kg·day (-1)) for 4 weeks. It was shown that AVE 0991 reduced left ventricular hypertrophy and improved heart function, characterized by decreases in left ventricular weight and left ventricular end-diastolic diameter, and increases in ejection fraction. Moreover, AVE 0991 significantly down-regulated mean myocyte diameter and attenuate the gene expression of the hypertrophic markers. Furthermore, AVE 0991 inhibited the expression of NOX 2 and NOX 4, meaning that AVE 0991 reduced oxidative stress of cardiac hypertrophy mice. Our data showed that AVE 0991 treatment could attenuate cardiac hypertrophy and improve heart function, which may be due to reduce oxidative stress.

  14. Cardiac abnormalities in adults with the attenuated form of mucopolysaccharidosis type I

    NARCIS (Netherlands)

    O.I.I. Soliman (Osama Ibrahim Ibrahim); R.G.M. Timmermans (Remco); A. Nemes (Attila); W.B. Vletter (Wim); J.H.P. Wilson (Paul); F.J. ten Cate (Folkert); M.L. Geleijnse (Marcel)

    2007-01-01

    textabstractBackground: Cardiac involvement in mucopolysaccharidosis type I (MPS I) has been studied primarily in its most severe forms. Cardiac involvement, particularly left ventricular (LV) systolic and diastolic function, in the attenuated form of MPS I is less well known. Methods: Cardiac funct

  15. Semiactive control for vibration attenuation

    Energy Technology Data Exchange (ETDEWEB)

    Leitmann, G. [Univ. of California, Berkeley, CA (United States). Coll. of Engineering

    1994-12-31

    With the advent of materials, such as electrorheological fluids, whose material properties can be altered rapidly by means of external stimuli, employing such materials as actuators for the controlled attenuation of undesirable vibrations is now possible. Such control schemes are dubbed semiactive in that they attenuate vibrations whether applied actively or passively. The author investigates various such control schemes, allowing for both separate and joint control of the stiffness and damping characteristics of the material.

  16. 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...

  17. 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.

  18. Rebuilding the US Health Left

    Directory of Open Access Journals (Sweden)

    Victor W. Sidel, MD

    2010-02-01

    Full Text Available With this issue Social Medicine begins a series of invited papers on the topic: “Rebuilding the US Health Left.” In this editorial we will outline our vision for this series. We undertake this project aware that our good friend and mentor, Dr. Walter Lear, one of the leading health activists of the 20th century, lies critically ill. Walter was the creator and custodian of the US Health Left Archives, a collection that is now with the University of Pennsylvania library. The collection reminds us of the important role left health care workers played in US history throughout the 20th century. They advocated for a national health program (Committee on the Costs of Medical Care, Physicians Forum, Medical Care Section/APHA, HealthPAC, Physicians for a National Health Program, National Physicians Alliance, provided international solidarity (American Soviet Medical Society, international brigades during the Spanish Civil War, Central American Solidarity Movement, Committee to Help Chilean Health Workers, Doctors for Global Health, traced the connections between disease and social class (Sigerist Circle, Spirit of 1848, APHA, fought for workers’ health (Councils for Occupational Safety and Health; Occupational Health and Safety Section, APHA participated in anti-war movements (Medical Committee for Human Rights, Physicians for Social Responsibility, International Physicians for the Prevention of Nuclear War, created new models of health care delivery (Health Cooperatives, Prepaid Health Maintenance Organizations, Community Health Centers, National Health Service Corps, Free Clinics, were central to the struggle for women’s rights (Planned Parenthood, Physicians for Reproductive Choice and Health, supported the civil rights movement both in medicine and in the broader society (National Medical Association, Medical Committee for Human Rights, played key roles in the movement for gay rights (ACT-UP, Gay & Lesbian Medical Association, Lesbian, Gay

  19. 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.

  20. Left Supraclavicular Spindle Cell Lipoma

    OpenAIRE

    Oladejo Olaleye; Bertram Fu; Ram Moorthy; Charles Lawson; Myles Black; David Mitchell

    2010-01-01

    Background. Spindle cell lipoma (SCL) is a benign lipomatous tumour, typically occurring in the posterior neck, shoulder or upper back of elderly males. They compose of fat, CD34 positive spindle cells, and ropey collagen on a myxoid matrix. 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...

  1. 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.

  2. Attenuation in Superconducting Circular Waveguides

    Directory of Open Access Journals (Sweden)

    K. H. Yeap

    2016-09-01

    Full Text Available We present an analysis on wave propagation in superconducting circular waveguides. In order to account for the presence of quasiparticles in the intragap states of a superconductor, we employ the characteristic equation derived from the extended Mattis-Bardeen theory to compute the values of the complex conductivity. To calculate the attenuation in a circular waveguide, the tangential fields at the boundary of the wall are first matched with the electrical properties (which includes the complex conductivity of the wall material. The matching of fields with the electrical properties results in a set of transcendental equations which is able to accurately describe the propagation constant of the fields. Our results show that although the attenuation in the superconducting waveguide above cutoff (but below the gap frequency is finite, it is considerably lower than that in a normal waveguide. Above the gap frequency, however, the attenuation in the superconducting waveguide increases sharply. The attenuation eventually surpasses that in a normal waveguide. As frequency increases above the gap frequency, Cooper pairs break into quasiparticles. Hence, we attribute the sharp rise in attenuation to the increase in random collision of the quasiparticles with the lattice structure.

  3. Facts about Hypoplastic Left Heart Syndrome

    Science.gov (United States)

    ... left and right sides of the heart: the patent ductus arteriosus and the patent foramen ovale . Normally, these openings ... functioning left side of the heart through the patent ductus arteriosus and the patent foramen ovale. The right side ...

  4. 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.

  5. Split Left GC-Lpp Semigroups

    Institute of Scientific and Technical Information of China (English)

    Zhen Zhen LI; Xiao Jiang GUO; Zhi Qing FU

    2012-01-01

    A left GC-lpp semigroup S is called split if the natural homomorphism γb of S onto S/γ induced by γ is split.It is proved that a left GC-lpp semigroup is split if and only if it has a left adequate transversal.In particular,a construction theorem for split left GC-lpp semigroups is established.

  6. Left supraclavicular spindle cell lipoma.

    Science.gov (United States)

    Olaleye, Oladejo; Fu, Bertram; Moorthy, Ram; Lawson, Charles; Black, Myles; Mitchell, David

    2010-01-01

    Background. Spindle cell lipoma (SCL) is a benign lipomatous tumour, typically occurring in the posterior neck, shoulder or upper back of elderly males. They compose of fat, CD34 positive spindle cells, and ropey collagen on a myxoid matrix. 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.

  7. 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.

  8. 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.

  9. 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…

  10. 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…

  11. 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

  12. Attenuation in silica-based optical fibers

    DEFF Research Database (Denmark)

    Wandel, Marie Emilie

    2006-01-01

    In this thesis on attenuation in silica based optical fibers results within three main topics are reported. Spectral attenuation measurements on transmission fibers are performed in the wide wavelength range 290 nm – 1700 nm. The measured spectral attenuation is analyzed with special emphasis...... on 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...... of the high attenuation measured in such fibers is described as being due to scattering of light on fluctuations of the core diameter. A novel semi-empirical model for predicting the attenuation of high index fibers is presented. The model is shown to be able to predict the attenuation of high index fibers...

  13. 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.

  14. 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.

  15. 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.

  16. 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".

  17. 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 bias...

  18. 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...

  19. Clinical psychomotor skills among left and right handed medical students: are the left-handed medical students left out?

    OpenAIRE

    2016-01-01

    Background There is a growing perception that the left handed (LH) medical students are facing difficulties while performing the clinical tasks that involve psychomotor skill, although the evidence is very limited and diverse. The present study aimed to evaluate the clinical psychomotor skills among Right-handed (RH) and left-handed (LH) medical students. Methods For this study, 54 (27 left handed and 27 right handed) first year medical students were selected. They were trained for different ...

  20. Ferrite attenuator modulation improves antenna performance

    Science.gov (United States)

    Hooks, J. C.; Larson, S. G.; Shorkley, F. H.; Williams, B. T.

    1970-01-01

    Ferrite attenuator inserted into appropriate waveguide reduces the gain of the antenna element which is causing interference. Modulating the ferrite attenuator to change the antenna gain at the receive frequency permits ground tracking until the antenna is no longer needed.

  1. 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.

  2. 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).

  3. Photonic crystal with left-handed components

    CERN Document Server

    Markos, Peter

    2015-01-01

    We show that the periodic array of left-handed cylinders possesses a rich spectrum of guided modes when the negative permeability of cylinders equals exactly to minus value of permeability of embedding media. These resonances strongly influences propagation of electromagnetic waves through photonic structures made from left-handed materials. A series of Fano resonances excited by incident wave destroys the band frequency spectrum of square array of left-handed cylinders and increases considerably the absorption of transmitted waves.

  4. 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.

  5. Left-sided omental torsion: CT appearance

    Energy Technology Data Exchange (ETDEWEB)

    Aoun, N.; Haddad-Zebouni, S.; Slaba, S.; Ghossain, M. [Hotel-Dieu de France Hospital, Beirut (Lebanon). Dept. of Radiology; Noun, R. [Hotel-Dieu de France Hospital, Beirut (Lebanon). Dept. of General Surgery

    2001-01-01

    A 34-year-old male presented with exquisite left flank pain. Computed tomography showed a hyperdense vascular structure surrounded by whirling linear streaks situated in the greater omentum under the splenic flexure of the colon. Omental stranding extended caudally into the pelvis where part of the inflamed omentum entered a left inguinal hernia sac. Surgery revealed left-sided torsion of the greater omentum. Left-sided omental torsion is infrequent and pre-operative diagnosis is rarely established. The CT findings of an omental fatty mass with a whirling pattern is characteristic of omental torsion. Preoperative diagnosis is important because conservative management has been suggested. (orig.)

  6. 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...

  7. Inhibition of NF-κB activity in the hypothalamic paraventricular nucleus attenuates hypertension and cardiac hypertrophy by modulating cytokines and attenuating oxidative stress

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Xiao-Jing [Department of Physiology and Pathophysiology, Xi' an Jiaotong University School of Basic Medical Sciences, Xi' an Jiaotong University Cardiovascular Research Center, Xi' an Jiaotong University Health Science Center, Xi' an 710061 (China); Zhang, Dong-Mei [Department of Physiology, Dalian Medical University, Dalian 116044 (China); Jia, Lin-Lin; Qi, Jie; Song, Xin-Ai; Tan, Hong [Department of Physiology and Pathophysiology, Xi' an Jiaotong University School of Basic Medical Sciences, Xi' an Jiaotong University Cardiovascular Research Center, Xi' an Jiaotong University Health Science Center, Xi' an 710061 (China); Cui, Wei [Department of Endocrinology and Metabolism, First Affiliated Hospital of Xi' an Jiaotong University, Xi' an Jiaotong University Health Science Center, Xi' an 710061 (China); Chen, Wensheng [Department of Cardiovascular Surgery, Xijing Hospital, Fourth Military Medical University, Xi' an 710032 (China); Zhu, Guo-Qing [Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing 210029 (China); Qin, Da-Nian, E-mail: dnqin@stu.edu.cn [Department of Physiology, Shantou University Medical College, Shantou 515041 (China); Kang, Yu-Ming, E-mail: ykang@mail.xjtu.edu.cn [Department of Physiology and Pathophysiology, Xi' an Jiaotong University School of Basic Medical Sciences, Xi' an Jiaotong University Cardiovascular Research Center, Xi' an Jiaotong University Health Science Center, Xi' an 710061 (China)

    2015-05-01

    We hypothesized that chronic inhibition of NF-κB activity in the hypothalamic paraventricular nucleus (PVN) delays the progression of hypertension and attenuates cardiac hypertrophy by up-regulating anti-inflammatory cytokines, reducing pro-inflammatory cytokines (PICs), attenuating nuclear factor-κB (NF-κB) p65 and NAD(P)H oxidase in the PVN of young spontaneously hypertensive rats (SHR). Young normotensive Wistar–Kyoto (WKY) and SHR rats received bilateral PVN infusions with NF–κB inhibitor pyrrolidine dithiocarbamate (PDTC) or vehicle for 4 weeks. SHR rats had higher mean arterial pressure and cardiac hypertrophy as indicated by increased whole heart weight/body weight ratio, whole heart weight/tibia length ratio, left ventricular weight/tibia length ratio, cardiomyocyte diameters of the left cardiac ventricle, and mRNA expressions of cardiac atrial natriuretic peptide (ANP) and beta-myosin heavy chain (β-MHC). These SHR rats had higher PVN levels of proinflammatory cytokines (PICs), reactive oxygen species (ROS), the chemokine monocyte chemoattractant protein-1 (MCP-1), NAD(P)H oxidase activity, mRNA expression of NOX-2 and NOX-4, and lower PVN IL-10, and higher plasma levels of PICs and NE, and lower plasma IL-10. PVN infusion of NF-κB inhibitor PDTC attenuated all these changes. These findings suggest that NF-κB activation in the PVN increases sympathoexcitation and hypertensive response, which are associated with the increases of PICs and oxidative stress in the PVN; PVN inhibition of NF-κB activity attenuates PICs and oxidative stress in the PVN, thereby attenuates hypertension and cardiac hypertrophy. - Highlights: • Spontaneously hypertensive rats exhibit neurohormonal excitation in the PVN. • PVN inhibition of NF-κB attenuates hypertension-induced cardiac hypertrophy. • PVN inhibition of NF-κB attenuates hypertension-induced neurohormonal excitation. • PVN inhibition of NF-κB attenuates hypertension-induced imbalance of cytokines

  8. 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. 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.

  2. 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.

  3. Surgical Treatment of Left Ventricular Pseudoaneurysm

    Science.gov (United States)

    Mujanovic, Emir; Bergsland, Jacob; Avdic, Sevleta; Stanimirovic-Mujanovic, Sanja; Kovacevic-Preradovic, Tamara; Kabil, Emir

    2014-01-01

    Introduction: Left ventricular pseudoaneurysm is a rare condition because in most instances ventricular free-wall rupture leads to fatal pericardial tamponade. Rupture of the free wall of the left ventricle is a cata­strophic complication of myocardial infarction, occurring in approximately 4% of pa­tients with infarcts, resulting in immediate collapse of the patient and electromechanical dissociation. In rare cases the rupture is contained by pericardial and fibrous tissue, and the result is a pseudoaneurysm. The left ventricular pseudoaneurysm contains only pericardial and fibrous elements in its wall-no myocardial tissue. Because such aneurysms have a strong tendency to rupture, this disorder may lead to death if it is left surgically untreated. Case report: In this case report, we present a patient who underwent successful repair of a left ventricular pseudoaneurysm, which followed a myocardial infarction that was caused by occlusion of the left circumflex coronary artery. Although repair of left ventricular pseudoaneurysm is still a surgical challenge, it can be performed with acceptable results in most patients. PMID:25568538

  4. 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.

  5. [Social aspects of left-handedness].

    Science.gov (United States)

    Milenković, Sanja; Belojević, Goran; Kocijancić, Radojka

    2010-01-01

    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 behavioural patterns appear in these people. This was a sort of provoked behaviour 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.

  6. 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.

  7. 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.

  8. 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).

  9. 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.

  10. Attenuation map reconstruction from TOF PET data

    CERN Document Server

    Yang, Qingsong; Wang, Ge

    2013-01-01

    To reconstruct a radioactive tracer distribution with positron emission tomography (PET), the background attenuation correction is needed to eliminate image artifacts. Recent research shows that time-of-flight (TOF) PET data determine the attenuation sinogram up to a constant, and its gradient can be computed using an analytic algorithm. In this paper, we study a direct estimation of the sinogram only from TOF PET data. First, the gradient of the attenuation sinogram is estimated using the aforementioned algorithm. Then, a relationship is established to link the differential attenuation sinogram and the underlying attenuation background. Finally, an iterative algorithm is designed to determine the attenuation sinogram accurately and stably. A 2D numerical simulation study is conducted to verify the correctness of our proposed approach.

  11. Optimal ultrasonic array focusing in attenuative media.

    Science.gov (United States)

    Ganguli, A; Gao, R X; Liang, K; Jundt, J

    2011-12-01

    This paper presents a parametric study on the efficiency of ultrasound focusing in an attenuative medium, using phased arrays. Specifically, an analytical model of ultrasound wave focusing in a homogeneous, isotropic and attenuative fluid with point sources is presented. Calculations based on the model have shown that in an attenuative medium, an optimum frequency exists for the best focusing performance for a particular size of aperture and focal distance. The effect of different f numbers on the focusing performance in the attenuative medium is further investigated. The information obtained from the analytical model provides insights into the design and installation of a phased transducer array for energy efficient wave focusing.

  12. Leptogenesis in left-right symmetric theories

    Energy Technology Data Exchange (ETDEWEB)

    Joshipura, Anjan S. E-mail: anjan@prl.ernet.in; Paschos, Emmanuel A. E-mail: paschos@physik.uni-dortmund.de; Rodejohann, Werner E-mail: rodejoha@xena.physik.uni-dortmund.de

    2001-09-17

    The masses and mixing of the light left-handed neutrinos can be related to those of the heavy right-handed neutrinos in left-right symmetric theories. Properties of the light neutrinos are measured in terrestrial experiments and the CP-violating decays of their heavy counterparts produce a baryon asymmetry via the well-known leptogenesis mechanism. The left-handed Higgs triplet, present in left-right symmetric theories, modifies the usual see-saw formula. It is possible to relate the lepton asymmetry to the light neutrino parameters when the triplet and the top quark through the usual see-saw mechanism give the dominant contribution to the neutrino mass matrix. We find that in this situation the small angle MSW and vacuum solutions produce reasonable asymmetry, whereas the large angle MSW case requires extreme fine-tuning of the three phases in the mixing matrix.

  13. Left-right symmetry and neutrino stability

    Energy Technology Data Exchange (ETDEWEB)

    Akhmedov, E.K. [Valencia Univ. (Spain). Dept. de Fisica Teorica; Joshipura, A.S. [Valencia Univ. (Spain). Dept. de Fisica Teorica; Ranfone, S. [Valencia Univ. (Spain). Dept. de Fisica Teorica; Valle, J.W.F. [Valencia Univ. (Spain). Dept. de Fisica Teorica

    1995-05-08

    We consider a left-right symmetric model in which neutrinos acquire mass due to the spontaneous violation of both the gauged B-L and a global U(1) symmetry broken by the vacuum expectation value (VEV) of a gauge singlet scalar boson left angle {sigma} right angle . For suitable choices of left angle {sigma} right angle consistent with all laboratory and astrophysical observations neutrinos will be unstable against majoron emission. All neutrino masses in the keV to MeV range are possible, since the expected neutrino decay lifetimes can be short enough to dilute their relic density below the cosmologically required level. A wide variety of possible new phenomena, associated to the presence of left-right symmetry and/or the global symmetry at the TeV scale, could therefore be observable, without conflict with cosmology. The latter includes the possibility of invisibly decaying higgs bosons, which can be searched at LEP, NLC and LHC. ((orig.)).

  14. Leptogenesis in left-right symmetric theories

    CERN Document Server

    Joshipura, A S; Rodejohann, W

    2001-01-01

    The masses and mixing of the light left-handed neutrinos can be related to those of the heavy right-handed neutrinos in left-right symmetric theories. Properties of the light neutrinos are measured in terrestrial experiments and the CP-violating decays of their heavy counterparts produce a baryon asymmetry via the well-known leptogenesis mechanism. The left-handed Higgs triplet, present in left-right symmetric theories, modifies the usual see-saw formula. It is possible to relate the lepton asymmetry to the light neutrino parameters when the triplet and the top quark through the usual see-saw mechanism give dominant contribution to the neutrino mass matrix. We find that in this situation the small angle MSW and vacuum solutions produce reasonable asymmetry, whereas the large angle MSW case requires extreme fine-tuning of the three phases in the mixing matrix.

  15. 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

  16. Thoracoscopic Left Splanchnicectomy: Two Trocar Technique

    OpenAIRE

    George Jinescu; Ion Lica; Septimiu Andrei; Cornelia Chidiosan; Mihnea Dinu

    2014-01-01

    Background: Abdominal hyperalgic syndrome in unresectable pancreatic cancer worsens the quality of patients' life. The goal of this article is to evaluate the feasibility of performing the left splanchnicectomy using a two trocar thoracoscopic approach. Material and Methods: One patient suffering from intractable pain due to unresectable pancreatic cancer (stage IV) with liver metastasis underwent thoracoscopic unilateral left splanchnicectomy. The procedure was performed using only two troca...

  17. Case series: Congenital left ventricular diverticulum

    Directory of Open Access Journals (Sweden)

    Shah Dharita

    2010-01-01

    Full Text Available Congenital left ventricular diverticulum is a rare cardiac malformation characterized by a localized outpouching from the cardiac chamber. The patient is usually asymptomatic. However, complications like embolism, infective endocarditis, arrhythmia and, rarely, rupture can be the initial presentation. Diagnosis can be established by USG, echocardiography, CT angiography, and MRI. We report here two neonates with congenital left ventricular apical diverticulum associated with epigastric hernia.

  18. 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...

  19. Wideband, 50 dB Attenuation Range Liquid Crystal Based Variable Optical Attenuator

    Institute of Scientific and Technical Information of China (English)

    J.J.; Pan; Henry; He; Eric; Zhang

    2003-01-01

    A compact variable optical attenuator, covering C and L bands with over 50 dB attenuation range, is realized using a single liquid crystal cell with a tilted fused silica coating compensating the cell's small residual birefringence.

  20. 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.

  1. 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.

  2. 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 $\\sqrt{H}$.

  3. DSM-5: ATTENUATED PSYCHOSIS SYNDROME?

    Directory of Open Access Journals (Sweden)

    Eduardo Fonseca-Pedrero

    2013-09-01

    Full Text Available Psychotic syndrome includes several devastating mental disorders characterized by a rupture of higher mental functions. The signs and symptoms of psychosis begin in adolescence or early adulthood and usually begin gradually and progress over time. Attenuated psychosis syndrome is a new DSM-5 diagnostic proposal which deals with identifying people at high-risk mental state (ARMS/UHR which may be a predictor of conversion to psychosis. The potential benefit would be that if psychotic disorder is treated more effectively in its early stages, it could produce a lasting beneficial effect that probably could not be achieved with later intervention. This syndrome has generated intense discussion in specialized scientific and professional forums, crisscrossing arguments in favor and against its inclusion. HRMS is preferentially evaluated in the adolescent or young adult population. HRMS evolution is associated with a higher rate of transition toward nonaffective psychosis, although it can evolve toward other mental disorders, remain stable or remit over time. Empirical evidence shows that early intervention seems to have a certain beneficial effect, although for now the results are still insufficient and contradictory. The lack of specificity of symptoms in predicting psychosis, presence of certain limitations (e.g., stigmatization, results found in early interventions and lack of empirical evidence, have led to include the attenuated psychosis syndrome in the DSM-5 Appendix III. The main benefits and limitations of including this supposed category, possible lessons learned from this type of study and future lines of action are discussed in the light of these findings.

  4. Attenuation characteristics of a light attenuator combined by polarizers with different extinction ratios

    Institute of Scientific and Technical Information of China (English)

    Huang Chong; Deng Peng; Zhao Shuang; Chen Hai-Qing

    2011-01-01

    This paper deals with a systematical analysis and an algorithm of attenuation characteristics of a light attenuator combined by n pieces of polarizers(n-LACP)whose extinction ratios are different from each other.The attenuation ratio expression of a two-LACP is deduced. We find that the monotonic attenuation interval depends on the first polarizer and that the attenuation range depends on the second one.For the three-LACP,a method for obtaining a monotonic attenuation interval is proposed.Moreover,the attenuation ratio expression is demonstrated.Analysis and experiment show that when the initial status of the three-LACP is at the maximum output,if the second or third polarizer rotates alone,the minimum attenuation ratios can reach K2-1and K3-1,respectively,and if the first polarizer rotates,a minimum attenuation ratio of K2-1K3-1can be obtained(K1,K2 and K3 represent the extinction ratios of the three polarizers in turn).Furthermore,the attenuation ratio expression of n-LACP and the relevant attenuation characteristics are proposed.The minimum attenuation ratio of an n-LACP is(K2K3...Kn)-1.

  5. 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...

  6. DISTURBANCE ATTENUATION FOR UNCERTAIN NONLINEAR CASCADED SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    BI Weiping; MU Xiaowu; SUN Yuqiang

    2004-01-01

    In present paper, the disturbance attenuation problem of uncertain nonlinear cascaded systems is studied. Based on the adding one power integrator technique and recursive design, a feedback controller that solves the disturbance attenuation problem is constructed for uncertain nonlinear cascaded systems with internal stability.

  7. Light attenuation on Chlorella vulgaris cells

    Science.gov (United States)

    Krol, Tadeusz; Lotocka, Maria

    1993-12-01

    The laboratory measurements of spectrum of light attenuation on phytoplankton particles i.e. monoculture of unicellural green algae Chlorella vulgaris are presented. The measurements were carried out for alive culture and the cultures subjected to chemical (NaOH) or physical (ultrasounds) modification. The distinct changes in the light attenuation spectrum were a result of modification of the internal cell structures.

  8. Attenuation coefficients for water quality trading.

    Science.gov (United States)

    Keller, Arturo A; Chen, Xiaoli; Fox, Jessica; Fulda, Matt; Dorsey, Rebecca; Seapy, Briana; Glenday, Julia; Bray, Erin

    2014-06-17

    Water quality trading has been proposed as a cost-effective approach for reducing nutrient loads through credit generation from agricultural or point source reductions sold to buyers facing costly options. We present a systematic approach to determine attenuation coefficients and their uncertainty. Using a process-based model, we determine attenuation with safety margins at many watersheds for total nitrogen (TN) and total phosphorus (TP) loads as they transport from point of load reduction to the credit buyer. TN and TP in-stream attenuation generally increases with decreasing mean river flow; smaller rivers in the modeled region of the Ohio River Basin had TN attenuation factors per km, including safety margins, of 0.19-1.6%, medium rivers of 0.14-1.2%, large rivers of 0.13-1.1%, and very large rivers of 0.04-0.42%. Attenuation in ditches transporting nutrients from farms to receiving rivers is 0.4%/km for TN, while for TP attenuation in ditches can be up to 2%/km. A 95 percentile safety margin of 30-40% for TN and 6-10% for TP, applied to the attenuation per km factors, was determined from the in-stream sensitivity of load reductions to watershed model parameters. For perspective, over 50 km a 1% per km factor would result in 50% attenuation = 2:1 trading ratio.

  9. Left ventricular performance during triggered left ventricular pacing in patients with cardiac resynchronization therapy and left bundle branch block

    DEFF Research Database (Denmark)

    Witt, Christoffer Tobias; Kronborg, Mads Brix; Nohr, Ellen Aagaard;

    2016-01-01

    PURPOSE: To assess the acute effect of triggered left ventricular pacing (tLVp) on left ventricular performance and contraction pattern in patients with heart failure, left bundle branch block (LBBB), and cardiac resynchronization therapy (CRT). METHODS: Twenty-three patients with pre-implant QRS...... conduction, tLVp, and BiV pacing and compared as paired data. Echocardiographic analysis was done blinded with respect to pacing mode. RESULTS: LVEF was significantly higher during BiV pacing (47 ± 11 %) compared with intrinsic conduction (43 ± 13 %, P = 0.001) and tLVp (44 ± 13 %, P = 0.001), while......V pacing. CONCLUSIONS: The acute effect of tLVp on LV systolic function and contraction pattern is significantly lower than the effect of BiV pacing and not different from intrinsic conduction in patients with LBBB and CRT....

  10. Left ventricular volume determination from single-photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Bunker, S.R.; Hartshorne, M.F.; Schmidt, W.P.; Cawthon, M.A.; Karl, R.D. Jr.; Bauman, J.M.; Howard, W.H. III; Rubal, B.J.

    1985-02-01

    To compare the accuracy of single-photon emission computed tomography (SPECT) with that of contrast cineangiography in measuring left ventricular end-diastolic volume, 25 consecutive patients undergoing catheterizaiton for coronary artery or valvular heart disease were first evaluated scintigraphically. SPECT volume values showed a high degree of correlation with those determined by angiography with a standard error of the estimate of 23 ml. SPECT offers a highly accurate and essentially noninvasive method for measuring chamber volumes that is independent of geometric assumptions about ventricular configuration and chest wall attenuation and does not require blood sample counting.

  11. 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.

  12. 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...... the spatial impulse response, whereas the field cannot readily be found for an attenuating medium. In this paper we present a simulation program capable of calculating the field in a homogeneous attenuating medium. The program splits the aperture into rectangles and uses a far-field approximation for each...... of the rectangles and sums all contributions to arrive at the spatial impulse response for the aperture and field point. This approach makes it possible to model all transducer apertures, and the program can readily calculate the emitted, pulse-echo and continuous wave field. Attenuation is included by splitting...

  13. 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

  14. 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...

  15. Contrasting Assessments of the Latin American Left

    Directory of Open Access Journals (Sweden)

    Paul Lawrence Haber

    2011-01-01

    Full Text Available The ability of the Latin American electoral left to make substantial progress on the social justice agenda while in office is much disputed. Two significant schools of thought are identified: one generally sympathetic and the other critical. This essay explores this argument with reference to Brazil, El Salvador, and Bolivia. At the heart of the debate is the relationship between social movements and political parties of the left. Should social movements collaborate with political parties of the left? While the critics raise important questions and concerns that are useful to illuminate the limitations of gradualism they do not present a viable strategy forward. The article concludes with the observation that the nature of this collaboration is a worthy subject of serious debate and reform proposals.

  16. Probabilistic Parsing Using Left Corner Language Models

    CERN Document Server

    Manning, C D; Manning, Christopher D.; Carpenter, Bob

    1997-01-01

    We introduce a novel parser based on a probabilistic version of a left-corner parser. The left-corner strategy is attractive because rule probabilities can be conditioned on both top-down goals and bottom-up derivations. We develop the underlying theory and explain how a grammar can be induced from analyzed data. We show that the left-corner approach provides an advantage over simple top-down probabilistic context-free grammars in parsing the Wall Street Journal using a grammar induced from the Penn Treebank. We also conclude that the Penn Treebank provides a fairly weak testbed due to the flatness of its bracketings and to the obvious overgeneration and undergeneration of its induced grammar.

  17. 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.

  18. [Left predominance of varices: myth or reality?].

    Science.gov (United States)

    Cornu-Thénard, A; Maraval, M; Boivin, P; Parpex, P

    1986-01-01

    The study of 843 legs operated for major varices shows that they are equally distributed between the two lower limbs (48.6% on the right, 51.4% on the left). There is little sex-determined variation in this distribution (410 women - 184 men), the main difference being that found in men: +4.6% on the left. Other studies carried out in Europe come to much the same conclusion. Two of these studies do, however, note a much clearer predominance of left-leg varices in men (+10%). For some studies, the lack of information about the type of varices being considered has proved troublesome (for example the many isolated telangiectasis and varices) and means that it is impossible to come to any exact conclusion. Clinical quantification is therefore desirable: at least it takes into account the diameter of the varices studied.

  19. 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.

  20. 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.

  1. 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

  2. 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.

  3. 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.

  4. Left Pulmonary Artery Thrombosis in a Neonate with Left Lung Hypoplasia

    Directory of Open Access Journals (Sweden)

    Matthias P. van Schendel

    2012-01-01

    Full Text Available Thrombotic events in neonates may origin from fetal life. A 4-day-old newborn infant with a family history of heterozygous type 1 protein C deficiency was diagnosed with left lung hypoplasia and left pulmonary artery thrombosis. Its source was prenatally closed ductus arteriosus. Surgical removal of the thrombus was performed.

  5. 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.

  6. Correlation of Left Atrial Diameter by Echocardiography and Left Atrial Volume by Computed Tomography

    NARCIS (Netherlands)

    Hof, Irene; Arbab-Zadeh, Armin; Scherr, Daniel; Chilukuri, Karuna; Dalal, Darshan; Abraham, Theodore; Lima, Joao; Calkins, Hugh

    2009-01-01

    Computed Tomography. Introduction: For patients undergoing catheter ablation of atrial fibrillation (AF), left atrial size is a predictor of recurrence of AF during follow-up. For this reason, major clinical trials have used a left atrial diameter (LAD) of more than 5.0 or 5.5 cm, assessed by echoca

  7. 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.

  8. [Congenital left sinus of Valsalva aneurysm].

    Science.gov (United States)

    Simões, M V; Figueira, R R; Barbato, D; Miziara, H L

    1991-01-01

    Two cases of left sinus of Valsalva congenital aneurysm (SVCA), incidentally found are described. The authors call attention on rarity of them, and present new concepts about their morphogenesis and incidence. They also suggested a higher incidence of asymptomatic and undiagnosed cases of SVCA should be considered.

  9. 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.

  10. Pathological Left-Handedness: An Explanatory Model.

    Science.gov (United States)

    Satz, Paul

    Reported was an explanatory conceptual model for pathological left-handedness (PLH) and related hypotheses, some of which could not be tested empirically due to lack of information. The model was reported to provide an explanation for the relationship between handedness and specific learning disability, and handedness and cerebral dominance for…

  11. 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

  12. Giant melanoma of the left thumb

    NARCIS (Netherlands)

    Zeebregts, CJAM; Schraffordt Koops, H.

    2000-01-01

    A 74-year-old female patient is described with a giant melanoma of the left thenar and concomitant bilateral pulmonary metastases. Palliative treatment consisted of a two-staged procedure in order to save the limb from amputation. Firstly, perfusion with gamma-interferon, tumour necrosis factor-alph

  13. Diastolic Left Ventricular Dysfunction : A Clinical Appraisal

    NARCIS (Netherlands)

    Bronzwaer, J.G.F.

    2003-01-01

    Diastolic left ventricular (LV) distensibility is determined by the material properties of the LV wall and by LV geometry (i.e., LV shape, LV volume and LV wall thickness). These material properties are influenced both by the physical structure of the LV myocardium and by the dynamic process of myoc

  14. 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).

  15. Liponeurocytoma of the Left Lateral Ventricle

    Directory of Open Access Journals (Sweden)

    Ahmet BEKAR

    2009-09-01

    Full Text Available Liponeurocytoma has been recognized recently as a distinct clinicopathological entity by the World Health Organization. Although there are few cases described in the literature it has been accepted as a benign lesion. Here we present a 55-year-old woman with a supratentorial intraventricular liponeurocytoma of the left lateral ventricle.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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 ...... measurements of the much larger reflection parameters, hence commonly used nonprecision instruments can be used to determine the transmission errors with sufficient accuracy for the highest precision obtainable in standard laboratories....

  2. Wave attenuation charcteristics of tethered float system

    Digital Repository Service at National Institute of Oceanography (India)

    Vethamony, P.

    and transmitted wave powers, transmission coefficients are computed. The results show that transmission coefficient does not vary with changes in wave height or water depth. When depth of submergence of float increases, wave attenuation decreases, showing... that the system performs well when it is just submerged. As float velocity decreases with increase in float size, transmission coefficient increases with increase in float size. The influence of wave period on wave attenuation is remarkable compared to other...

  3. 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....

  4. 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.

  5. Light attenuation in estuarine mangrove lakes

    Science.gov (United States)

    Frankovich, Thomas A.; Rudnick, David T.; Fourqurean, James W.

    2017-01-01

    Submerged aquatic vegetation (SAV) cover has declined in brackish lakes in the southern Everglades characterized by low water transparencies, emphasizing the need to evaluate the suitability of the aquatic medium for SAV growth and to identify the light attenuating components that contribute most to light attenuation. Underwater attenuation of downwards irradiance of photosynthetically active radiation (PAR) was determined over a three year period at 42 sites in shallow (lakes in two sub-estuaries in the coastal Everglades, Florida USA. Turbidity, chromophoric dissolved organic matter (CDOM), and phytoplankton chlorophyll a (chl a) were measured concurrently and their respective contributions to the light attenuation rate were estimated. Light transmission to the benthos relative to literature estimates of minimum requirements for SAV growth indicated that the underwater light environment was often unsuitable for SAV. Light attenuation rates (n = 417) corrected for solar elevation angles ranged from 0.16 m-1 to 9.83 m-1 with a mean of 1.73 m-1. High concentrations of CDOM with high specific light absorption contributed the most to light attenuation followed by turbidity and chl a. CDOM alone sufficiently reduces light transmission beyond the estimated limits for SAV growth, making it difficult for ecosystem managers to increase SAV abundance by management activities. Light limitation of SAV in these areas may be a persistent feature because of their proximity to CDOM source materials from the surrounding mangrove swamp. Increasing freshwater flow into these areas may dilute CDOM concentrations and improve the salinity and light climate for SAV communities.

  6. Visual perceptual load induces inattentional deafness.

    Science.gov (United States)

    Macdonald, James S P; Lavie, Nilli

    2011-08-01

    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 presented simultaneously with the visual task display on a final trial. Failures to notice the presence of this tone (i.e., inattentional deafness) reached a rate of 79% in the high-visual-load condition, significantly more than in the low-load condition. These findings establish the phenomenon of inattentional deafness under visual load, thereby extending the load theory of attention (e.g., Lavie, Journal of Experimental Psychology. Human Perception and Performance, 25, 596-616, 1995) to address the cross-modal effects of visual perceptual load.

  7. Reconstruction of the left-sided brachiocephalic trunk after vascular ring operation in left-handed child with Kommerell's diverticulum.

    Science.gov (United States)

    Haponiuk, Ireneusz; Paczkowski, Konrad; Chojnicki, Maciej; Jaworski, Radosław; Steffens, Mariusz; Szofer-Sendrowska, Aneta; Kwaśniak, Ewelina; Zieliński, Jacek; Gierat-Haponiuk, Katarzyna

    2013-01-01

    We report a case of a 2-year-old girl with prenatal diagnosis of vascular ring composed of a right-sided aortic arch, a left ligamentum arteriosum, and a left subclavian artery (arteria lusoria sin) originating from a retroesophageal Kommerell's diverticulum, who was referred for surgery with symptoms related to local compression - severe dysphagia and respiratory disorders. Through the left posterolateral thoracotomy, a ligamentum arteriosum between the Kommerell's diverticulum and the left pulmonary artery was divided and because of left-handedness of the child a brachiocephalic trunk was reconstructed in the fashion of anastomosis of the left subclavian artery and the left common carotid artery, originating from the ascending aorta.

  8. 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.

  9. 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.

  10. Myocardial infarction and left ventricular remodeling: results of the CEDIM trial. Carnitine Ecocardiografia Digitalizzata Infarto Miocardico.

    Science.gov (United States)

    Colonna, P; Iliceto, S

    2000-02-01

    Left ventricular dilatation after acute myocardial infarction (MI) is a powerful predictor of progressive functional deterioration, culminating in heart failure and death. The most important determinants of post-MI left ventricular remodeling are the size of the infarct, the degree of residual stenosis in the infarct-related artery, and the viability of the infarct zone. In addition to reperfusion therapy and angiotensin-converting enzyme inhibition, metabolic intervention with L-carnitine may represent a therapeutic approach for preventing left ventricular dilatation and preserving cardiac function. Ongoing studies with early metabolic intervention with carnitine in the acute phase of infarction may prove successful in protecting the microcirculation against ischemic damage and enhancing its ability to respond to blood flow resumption. The results of the multicenter, randomized, double-blind Carnitine Ecocardiografia Digitalizzata Infarto Miocardico (CEDIM) trial suggest that the early and long-term administration of L-carnitine attenuates progressive left ventricular dilatation after acute anterior MI. Results show significant, consistent reductions in end-diastolic volume and end-systolic volume in patients who received L-carnitine compared with placebo. The ongoing CEDIM-2 trial (projected 4000 patients with acute MI) will assess the efficacy of L-carnitine in reducing the combined incidence of death and heart failure at 6 months. In addition to standard reperfusion therapy and angiotensin-converting enzyme inhibition, metabolic intervention with L-carnitine may be a therapeutic approach for preventing left ventricular dilatation and preserving cardiac function by limiting infarct size, decreasing residual stenosis in the infarct-related artery, and increasing viability of the infarct zone.

  11. Left-right symmetry and neutrino stability

    CERN Document Server

    Akhmedov, E K; Ranfone, S; Valle, José W F; Joshipura, A S; Ranfone, S; Valle, J W F

    1995-01-01

    We consider a left-right symmetric model in which neutrinos acquire mass due to the spontaneous violation of both the gauged B-L and a global U(1) symmetry broken by the vacuum expectation value (VEV) of a gauge singlet scalar boson \\VEV{\\sigma}. For suitable choices of \\VEV{\\sigma} consistent with all laboratory and astrophysical observations neutrinos will be unstable against majoron emission. All neutrino masses in the keV to MeV range are possible, since the expected neutrino decay lifetimes can be short enough to dilute their relic density below the cosmologically required level. A wide variety of possible new phenomena, associated to the presence of left-right symmetry and/or the global symmetry at the TeV scale, could therefore be observable, without conflict with cosmology. The latter includes the possibility of invisibly decaying higgs bosons, which can be searched at LEP, NLC and LHC.

  12. 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.

  13. Left Realism and Social Democratic Renewal

    Directory of Open Access Journals (Sweden)

    Russell Hogg

    2016-09-01

    Full Text Available At its inception Left Realism argued the need to develop a radical social democratic approach to crime. I argue that its contribution and continuing relevance primarily lies in this political project, the need for which has not dissipated. But this can only be advanced as an integral component of a more general renewal of social democratic ideas and politics that challenges the hegemony of neo-liberalism. This is far from guaranteed. The possibilities and challenges after the global financial crisis are considered. I argue for a rethinking of some core themes from early Left Realism to (as I see it better complement the task of social democratic renewal in the present.

  14. 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.

  15. 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.

  16. A constrained supersymmetric left-right model

    CERN Document Server

    Hirsch, Martin; Opferkuch, Toby; Porod, Werner; Staub, Florian

    2016-01-01

    We present a supersymmetric left-right model which predicts gauge coupling unification close to the string scale and extra vector bosons at the TeV scale. The subtleties in constructing a model which is in agreement with the measured quark masses and mixing for such a low left-right breaking scale are discussed. It is shown that in the constrained version of this model radiative breaking of the gauge symmetries is possible and a SM-like Higgs is obtained. Additional CP-even scalars of a similar mass or even much lighter are possible. The expected mass hierarchies for the supersymmetric states differ clearly from those of the constrained MSSM. In particular, the lightest down-type squark, which is a mixture of the sbottom and extra vector-like states, is always lighter than the stop. We also comment on the model's capability to explain current anomalies observed at the LHC.

  17. 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...... are investigated via simulation studies, and the suggested estimators are used in a study of prostate cancer based on the Finnish twin cohort where a twin pair is included only if both twins were alive in 1974....

  18. 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.

  19. 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.

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

    Science.gov (United States)

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

    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 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. PMID:23050168

  1. 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...

  2. 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.

  3. Hypersexuality from resection of left occipital arteriovenous malformation.

    Science.gov (United States)

    Cao, Yong; Zhu, Zhaohui; Wang, Rong; Wang, Shuo; Zhao, Jizong

    2010-01-01

    The authors report their experience on one patient with hypersexuality from resection of left occipital arteriovenous malformation. To the best of our knowledge, this is the first case reported in the literature. A 35-year-old right-handed female farmer suffered a sudden left occipital hemorrhage with subarachnoid and subdural hemorrhages of the left hemisphere. Transient left uncal herniation occurred at the onset and was released by conservative treatment. Digital subtraction angiography showed a brain left occipital arteriovenous malformation. After microsurgical resection of the arteriovenous malformation, the patient developed hypersexual behavior. Positron emission tomography showed hypermetabolism in the left frontal region and left posterior hippocampal gyrus and hypometabolism in the left anterior hippocampal gyrus and the left occipital surgical area. Theories concerning normal pressure perfusion breakthrough and specific areas in the brain responsible for the human sexual response are discussed.

  4. 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.

  5. Attenuation tomography in West Bohemia/Vogtland

    Science.gov (United States)

    Mousavi, Sima; Haberland, Christian; Bauer, Klaus; Hejrani, Babak; Korn, Michael

    2017-01-01

    We present a three-dimensional (3-D) P-wave attenuation (Qp) model for the geodynamically active swarm earthquake area of West Bohemia/Vogtland in the Czech/German border region. Path-averaged attenuation t* is calculated from amplitude spectra of time windows around the P-wave arrivals of local earthquakes. Average t/t* value or Qp for stations close to Nový Kostel are very low (focal zone (increases up to 500 within 80 km distance). The SIMUL2000 tomography scheme is used to invert the t* for P-wave attenuation perturbation. Analysis of resolution shows that our model is well-resolved in the vicinity of earthquake swarm hypocenters. The prominent features of the model are located around Nový Kostel focal zone and its northern vicinity. Beneath Nový Kostel a vertically stretched (down to depth of 11 km) and a highly attenuating body is observed. We believe that this is due to fracturing and high density of cracks inside the weak earthquake swarm zone in conjunction with presence of free gas/fluid. Further north of Nový Kostel two highly attenuating bodies are imaged which could represent fluid channels toward the surface. The eastern anomaly shows a good correlation with the fluid accumulation area which was suggested in 9HR seismic profile.

  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. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. 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.

  14. Left ventricular heart failure and pulmonary hypertension†

    Science.gov (United States)

    Rosenkranz, Stephan; Gibbs, J. Simon R.; Wachter, Rolf; De Marco, Teresa; Vonk-Noordegraaf, Anton; Vachiéry, Jean-Luc

    2016-01-01

    In patients with left ventricular heart failure (HF), the development of pulmonary hypertension (PH) and right ventricular (RV) dysfunction are frequent and have important impact on disease progression, morbidity, and mortality, and therefore warrant clinical attention. Pulmonary hypertension related to left heart disease (LHD) by far represents the most common form of PH, accounting for 65–80% of cases. The proper distinction between pulmonary arterial hypertension and PH-LHD may be challenging, yet it has direct therapeutic consequences. Despite recent advances in the pathophysiological understanding and clinical assessment, and adjustments in the haemodynamic definitions and classification of PH-LHD, the haemodynamic interrelations in combined post- and pre-capillary PH are complex, definitions and prognostic significance of haemodynamic variables characterizing the degree of pre-capillary PH in LHD remain suboptimal, and there are currently no evidence-based recommendations for the management of PH-LHD. Here, we highlight the prevalence and significance of PH and RV dysfunction in patients with both HF with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF), and provide insights into the complex pathophysiology of cardiopulmonary interaction in LHD, which may lead to the evolution from a ‘left ventricular phenotype’ to a ‘right ventricular phenotype’ across the natural history of HF. Furthermore, we propose to better define the individual phenotype of PH by integrating the clinical context, non-invasive assessment, and invasive haemodynamic variables in a structured diagnostic work-up. Finally, we challenge current definitions and diagnostic short falls, and discuss gaps in evidence, therapeutic options and the necessity for future developments in this context. PMID:26508169

  15. Left atrium segmentation for atrial fibrillation ablation

    Science.gov (United States)

    Karim, R.; Mohiaddin, R.; Rueckert, D.

    2008-03-01

    Segmentation of the left atrium is vital for pre-operative assessment of its anatomy in radio-frequency catheter ablation (RFCA) surgery. RFCA is commonly used for treating atrial fibrillation. In this paper we present an semi-automatic approach for segmenting the left atrium and the pulmonary veins from MR angiography (MRA) data sets. We also present an automatic approach for further subdividing the segmented atrium into the atrium body and the pulmonary veins. The segmentation algorithm is based on the notion that in MRA the atrium becomes connected to surrounding structures via partial volume affected voxels and narrow vessels, the atrium can be separated if these regions are characterized and identified. The blood pool, obtained by subtracting the pre- and post-contrast scans, is first segmented using a region-growing approach. The segmented blood pool is then subdivided into disjoint subdivisions based on its Euclidean distance transform. These subdivisions are then merged automatically starting from a seed point and stopping at points where the atrium leaks into a neighbouring structure. The resulting merged subdivisions produce the segmented atrium. Measuring the size of the pulmonary vein ostium is vital for selecting the optimal Lasso catheter diameter. We present a second technique for automatically identifying the atrium body from segmented left atrium images. The separating surface between the atrium body and the pulmonary veins gives the ostia locations and can play an important role in measuring their diameters. The technique relies on evolving interfaces modelled using level sets. Results have been presented on 20 patient MRA datasets.

  16. 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.

  17. Degenerate Neutrinos in Left Right Symmetric Theory

    OpenAIRE

    Joshipura, Anjan S.

    1994-01-01

    Various hints on the neutrino masses namely, ({\\em i}) the solar neutrino deficit ({\\em ii}) the atmospheric neutrino deficit ({\\em iii}) the need for the dark matter and/or ({\\em iv}) the non-zero neutrinoless double beta decay collectively imply that all the three neutrinos must be nearlty degenerate. This feature can be understood in the left right symmetric theory. We present a model based on the group $SU(2)_{L}\\times SU(2)_R\\times U(1)_{B-L}\\times SU(2)_H$ which can explain the required...

  18. Between Right and Left Handed Media

    CERN Document Server

    Ingrey, P C; Jakeman, E; French, O E

    2008-01-01

    We report analytical calculations for the propagation of electromagnetic radiation through an inhomogeneous layer whose refractive index varies in one dimension situated between bulk right- and left-handed media. Significant field localization is generated in the layer that is caused by the coherent superposition of evanescent waves. The strength of the field localization and the transmission properties of the layer are investigated as a function of the layer width, losses and defects in the refractive index; the former two being modelled by continuous changes, and the latter by discontinuous changes, in the index profile.

  19. Preventive effect of yuzu and hesperidin on left ventricular remodeling and dysfunction in rat permanent left anterior descending coronary artery occlusion model.

    Directory of Open Access Journals (Sweden)

    Hye Yon Yu

    Full Text Available Left ventricular (LV remodeling, which includes ventricular dilatation and increased interstitial fibrosis after myocardial infarction (MI, is the critical process underlying the progression to heart failure. Therefore, a novel approach for preventing LV remodeling after MI is highly desirable. Yuzu is a citrus plant originating in East Asia, and has a number of cardioprotective properties such as hesperidin. However, no study has proved whether yuzu can prevent LV remodeling. The aim of this study was to determine the effects of yuzu on heart failure (HF and its potential impact on the LV remodeling process after MI. Our in vivo study using the permanent left anterior descending coronary artery (LAD occlusion model demonstrate that one week pre-treatment with yuzu or its major metabolite hesperidin before LAD occlusion significantly attenuated cardiac dysfunction, myocyte apoptosis and inflammation. Not only yuzu but also hesperidin inhibited caspase-3 activity, myeloperoxidase expression, α-smooth muscle actin expression, and matrix metalloproteinase-2 activity in a permanent LAD occlusion rat model. To our knowledge, our findings provide the first evidence that yuzu and hesperidin prevent MI-induced ventricular dysfunction and structural remodeling of myocardium.

  20. Preventive effect of yuzu and hesperidin on left ventricular remodeling and dysfunction in rat permanent left anterior descending coronary artery occlusion model.

    Science.gov (United States)

    Yu, Hye Yon; Ahn, Ji Hun; Park, Se Won; Jung, Yi-Sook

    2015-01-01

    Left ventricular (LV) remodeling, which includes ventricular dilatation and increased interstitial fibrosis after myocardial infarction (MI), is the critical process underlying the progression to heart failure. Therefore, a novel approach for preventing LV remodeling after MI is highly desirable. Yuzu is a citrus plant originating in East Asia, and has a number of cardioprotective properties such as hesperidin. However, no study has proved whether yuzu can prevent LV remodeling. The aim of this study was to determine the effects of yuzu on heart failure (HF) and its potential impact on the LV remodeling process after MI. Our in vivo study using the permanent left anterior descending coronary artery (LAD) occlusion model demonstrate that one week pre-treatment with yuzu or its major metabolite hesperidin before LAD occlusion significantly attenuated cardiac dysfunction, myocyte apoptosis and inflammation. Not only yuzu but also hesperidin inhibited caspase-3 activity, myeloperoxidase expression, α-smooth muscle actin expression, and matrix metalloproteinase-2 activity in a permanent LAD occlusion rat model. To our knowledge, our findings provide the first evidence that yuzu and hesperidin prevent MI-induced ventricular dysfunction and structural remodeling of myocardium.

  1. 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...

  2. Surgical Management of Intramyocardial Left Anterior Descending Artery.

    Science.gov (United States)

    De Salvatore, Sergio; Segreto, Antonio; Chiusaroli, Alessandro; Congiu, Stefano; Bizzarri, Federico

    2015-11-01

    An intramyocardial left anterior descending artery can be found in up to 30% of patients undergoing coronary artery bypass graft procedures. We review the various techniques available to identify an intramyocardial left anterior descending artery.

  3. 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.

  4. 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.

  5. 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...

  6. Tamponade by an expanding left ventricular pseudoaneurysm: A unique presentation.

    Science.gov (United States)

    Mahesh, Balakrishnan; Ong, Ping; Kutty, Ramesh; Abu-Omar, Yasir

    2015-10-01

    Left ventricular free wall rupture secondary to myocardial infarction is an uncommon but catastrophic event requiring emergency surgery. We describe a unique presentation of left ventricular free wall rupture as delayed tamponade caused by a gradually expanding pseudoaneurysm compressing the left atrium, leading to pulmonary congestion that required increasing respiratory support to maintain oxygenation, and necessitated emergency surgery. We discuss the options available to treat pseudoaneurysms due to left ventricular free wall rupture.

  7. 烟酰胺对压力诱发免腰椎间盘退变的保护作用%Protective effects of Niacinamide against axial loading induced degeneration of rabbit lumbar disc

    Institute of Scientific and Technical Information of China (English)

    周建国; 杨述华; 杨操; 邵增务; 徐蔚蔚; 郭兵; 俞旭东; 熊蠡茗

    2009-01-01

    的椎间盘恢复.%BACKGROUND:Recent studies have demonstrated that Niacinamide is capable of promoting the proliferation of intervertebral cells and improving intervertebral disc degeneration.Overloading is thought to the main cause of intervertebral disc degeneration.However,the protective effects of Niacinamide in loading induced intervertebral disc degeneration remains uncertain,OBJECTIVE:To investigate the protective effects of Niacinamide against axial loading induced degeneration of rabbit lumbar disc.DESIGN,TIME AND SETTING:A randomized controlled experiment was carded out in the Central Laboratory and the Laboratory of Department of Orthopaedics,Union Hospital Affiliated to Tongji Medical College,Huazhong University of Science and Technology from November 2008 to April 2009.MATERIALS:Twenty-four Japanese white rabbits (4 months old,weighing 2.0 kg).Niacinamide was supplied by Tianjin Damao Chemical Reagent Factory.METHODS:Twenty-four Japanese white rabbits were randomly divided into 6 groups.The controllable axial loading induced rabbit lumbar disc degeneration model was adopted to impose 98N pressure on the rabbit discs to induce degeneration.Various doses of Niacinamide were given intragastrically to the rabbits in different groups:2 rabbits in group 1,the loading device was installed without pressing,and no Niacinamide was given;2 rabbits in group 2,given 50 mg/kg Niacinamide for 1 week;5 rabbits in group 3,loaded with 98N for 1 week;5 rabbits in group 4,loaded with 98N for 1 week,then the pressure was released for another week's recovery;5 rabbits in group 5,loaded with 98N and given 50 mg/kg Niacinamide for 1 week;5 rabbits in group 6,loaded with 98N for 1 week and then the pressure was released for another week's recovery,50 mg/kg Niacinamide was continually given during the 2 weeks.MAIN OUTCOME MEASURES:Magnetic resonance image and Thompson's grading system were used to assess degeneration degree of the discs;hematoxylin and eosin staining,immunohistochemical staining for type Ⅱ collagen

  8. Coronary artery to left ventricle fistula

    Directory of Open Access Journals (Sweden)

    Kumar Vivek

    2005-11-01

    Full Text Available Abstract Background Coronary cameral fistulas are an uncommon entity, the etiology of which may be congenital or traumatic. They involve abnormal termination of a coronary artery, usually the right coronary, into a cardiac chamber, usually the right ventricle. Case Presentation We describe a case of female patient with severe aortic stenosis and interventricular septal hypertrophy that underwent bioprosthetic aortic valve replacement with concomitant septal myectomy. On subsequent follow-up an abnormal flow traversing the septum into the left ventricle was identified and Doppler interrogation demonstrated a continuous flow, with a predominantly diastolic component, consistent with coronary arterial flow. Conclusion The literature on coronary cameral fistulas is reviewed and the etiology of the diagnostic findings discussed. In our patient, a coronary artery to left ventricle fistula was the most likely explanation secondary to trauma to the septal perforator artery during myectomy. Since the patient was asymptomatic at the time of diagnosis no intervention was recommended and has done well on follow-up.

  9. 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.

  10. 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.

  11. 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.

  12. 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

    applying new strict ECG criteria subsequent rates of response in DCM were 18/19 (95%) and in IHD of 18/23 (78%) respectively, p... 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....

  13. 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.

  14. 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)

  15. 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…

  16. 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…

  17. 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…

  18. Touch Attenuates Infants' Physiological Reactivity to Stress

    Science.gov (United States)

    Feldman, Ruth; Singer, Magi; Zagoory, Orna

    2010-01-01

    Animal studies demonstrate that maternal touch and contact regulate infant stress, and handling during periods of maternal deprivation attenuates the stress response. To measure the effects of touch on infant stress reactivity during simulated maternal deprivation, 53 dyads were tested in two paradigms: still-face (SF) and still-face with maternal…

  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. GPR measurements of attenuation in concrete

    Energy Technology Data Exchange (ETDEWEB)

    Eisenmann, David, E-mail: djeisen@cnde.iastate.edu; Margetan, Frank J., E-mail: djeisen@cnde.iastate.edu; Pavel, Brittney, E-mail: djeisen@cnde.iastate.edu [Center for Nondestructive Evaluation, Iowa State University, 1915 Scholl Road, Ames, IA 50011-3042 (United States)

    2015-03-31

    Ground-penetrating radar (GPR) signals from concrete structures are affected by several phenomenon, including: (1) transmission and reflection coefficients at interfaces; (2) the radiation patterns of the antenna(s) being used; and (3) the material properties of concrete and any embedded objects. In this paper we investigate different schemes for determining the electromagnetic (EM) attenuation of concrete from measured signals obtained using commercially-available GPR equipment. We adapt procedures commonly used in ultrasonic inspections where one compares the relative strengths of two or more signals having different travel paths through the material of interest. After correcting for beam spread (i.e., diffraction), interface phenomena, and equipment amplification settings, any remaining signal differences are assumed to be due to attenuation thus allowing the attenuation coefficient (say, in dB of loss per inch of travel) to be estimated. We begin with a brief overview of our approach, and then discuss how diffraction corrections were determined for our two 1.6 GHz GPR antennas. We then present results of attenuation measurements for two types of concrete using both pulse/echo and pitch/catch measurement setups.

  1. Naloxone-Reversible Modulation of Pain Circuitry by Left Prefrontal rTMS

    Science.gov (United States)

    Taylor, Joseph J; Borckardt, Jeffrey J; Canterberry, Melanie; Li, Xingbao; Hanlon, Colleen A; Brown, Truman R; George, Mark S

    2013-01-01

    A 20-minute session of 10 Hz repetitive transcranial magnetic stimulation (rTMS) of Brodmann Area (BA) nine of the left dorsolateral prefrontal cortex (DLPFC) can produce analgesic effects on postoperative and laboratory-induced pain. This analgesia is blocked by pretreatment with naloxone, a μ-opioid antagonist. The purpose of this sham-controlled, double-blind, crossover study was to identify the neural circuitry that underlies the analgesic effects of left DLPFC rTMS, and to examine how the function of this circuit, including midbrain and medulla, changes during opioid blockade. Fourteen healthy volunteers were randomized to receive intravenous saline or naloxone immediately before sham and real left DLPFC rTMS on the same experimental visit. One week later, each participant received the novel pretreatment but the same stimulation paradigm. Using short sessions of heat on capsaicin-sensitized skin, hot allodynia was assessed during 3 Tesla functional magnetic resonance imaging (fMRI) scanning at baseline, post-sham rTMS, and post-real rTMS. Data were analyzed using whole-brain voxel-based analysis, as well as time series extractions from anatomically-defined regions of interest representing midbrain and medulla. Consistent with previous findings, real rTMS significantly reduced hot allodynia pain ratings. This analgesia was associated with elevated blood oxygenation-level dependent (BOLD) signal in BAs 9 and 10, and diminished BOLD signal in the anterior cingulate, thalamus, midbrain, and medulla during pain. Naloxone pretreatment largely abolished rTMS-induced analgesia, as well as rTMS-induced attenuation of BOLD signal response to painful stimuli throughout pain processing regions, including midbrain and medulla. These preliminary results suggest that left DLPFC rTMS drives top-down opioidergic analgesia. PMID:23314221

  2. Sizes of mantle heteogeneities and seismic attenuation

    Science.gov (United States)

    Ricard, Y. R.; durand, S.; Chambat, F.; Montagner, J.

    2013-12-01

    The small scale heterogeneity of the mantle, being mostly due to the mixing of petrological heterogeneities by a smooth but chaotic convection 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 spectrums. We show that a seismic wave of wavenumber k_0 crossing such medium is partly reflected by the heterogeneities and the scattered energy has an energy found proportional to k_0 S(2k_0). The reduction of energy for the propagating wave appears therefore equivalent to a quality factor 1/Q proportional to k_0 S(2k_0). 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 there are not unreasonable and we discuss how they are likely overestimated. In this case, most of the attenuation of the Earth would be due to small scale scattering by laminations not by intrinsic dissipation. Intrinsic dissipation must certainly exists but might correspond to a larger, yet unobserved Q. This provocative result would explain the observed very weak frequency dependence of the attenuation, and the fact that bulk attenuation seems negligeable, two observations that have been difficult to explain for 50 years.

  3. Accessory left gastric artery: angiographic anatomy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kang Soo; Lim, Hyung Guhn; Kim, Hong Soo; Jeon, Doo Sung [Presbyterian Medical Center, Chunju (Korea, Republic of); Chung, Jin Wook; Park, Jae Hyung [College of Medicine and the Institute of Radiation Medicine, Seoul National University, Seoul (Korea, Republic of); Song, Soon Young [Myongji Hospital, College of Medicine, Kwandong University, Seoul (Korea, Republic of)

    2000-09-01

    To evaluate the angiographic anatomy of the accessory left gastric artery (accLGA). We evaluated the angiographic findings of the accLGA in 50 patients (Angiostar; Siemens, Erlangen, Germany). Performing celiac and selective angiography in 50 and 34 patients, respectively. By means of celiac angiography, (1) site of origin, (2) anatomical course, (3) diameter, (4) degree of tortuosity, and (5) distal tapering were evaluated, while selective angiography was used to determine (1) arterial branching, (2) area of blood supply, and (3) patterns of gastric wall stain. Celiac angiography showed that the accLGA arose from the left hepatic artery (LHA) in 45 cases (90%) and from the proper hepatic artery in five (10%). If the accLGA arose from the LHA, its origin entirely depended on the branching pattern of the latter. It always arose from the lateral branch of the LHA furthest to the left and uppermost, and proximal to its umbilical point. The most common anatomical course of the accLGA, seen in 27 cases (54%), was between the S2 and S3 segmental branch. The diameter and degree of tortuosity of the accLGA were similar to those of adjacent intrahepatic branches in 21 (42%) and 33 cases (66%), respectively. The degree of tapering was less than that of adjacent intrahepatic vessel in 28 (56%). Selective angiography demonstrated esophageal branching of the acc LGA in 27 cases (79%), inferior phrenic arterial branching in three (9%), a mediastinal branch in one (3%), and hypervascularity of the lung in one (3%). In 15 cases (44%), bifurcation of the accLGA was recognized. The vascular territory of the accLGA was the gastric fundus together with the distal esophagus in 21 cases (62%), mainly the gastric fundus in six (18%), and mainly the distal esophagus in four (12%). The pattern of gastric mucosal stain was curvilinear wall in 31 cases (91%) and nodular in three (9%). A knowledge of the angiographic anatomy of the accLGA facilitates accurate recognition of this artery on

  4. 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.

  5. 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.

  6. Related anomalies of origin of left vertebral and left inferior thyroid arteries

    Energy Technology Data Exchange (ETDEWEB)

    Sartor, K.; Freckmann, N.; Boeker, D.K.

    1981-01-01

    The known rare occurrence of related anomalies of origin of vertebral and inferior thyroid arteries appears not to be documented in the angiographic literature. Three cases with manifestation on the left side are presented. Embryology is discussed briefly. Knowledge of such anomalies is of importance to surgeons as well as angiographers.

  7. 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…

  8. 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…

  9. 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.

  10. Degenerate Neutrinos in Left Right Symmetric Theory

    CERN Document Server

    Joshipura, A S

    1995-01-01

    Various hints on the neutrino masses namely, ({\\em i}) the solar neutrino deficit ({\\em ii}) the atmospheric neutrino deficit ({\\em iii}) the need for the dark matter and/or ({\\em iv}) the non-zero neutrinoless double beta decay collectively imply that all the three neutrinos must be nearlty degenerate. This feature can be understood in the left right symmetric theory. We present a model based on the group $SU(2)_{L}\\times SU(2)_R\\times U(1)_{B-L}\\times SU(2)_H$ which can explain the required departures from degeneracy in neutrino masses and large mixing among them without assuming any of the mixing in the quark or charged lepton sector to be large as would be expected in a typical $SO(10)$ model.

  11. LEFT RENAL TUMOR: A RARE CADAVERIC FINDINGS

    Directory of Open Access Journals (Sweden)

    Siva Prasad

    2015-08-01

    Full Text Available A benign tumour is a non - cancerous growth that does not spread (metastasize to other parts of the body and is not usually life - threatening. Many researchers believe that most of the following types of kidney tumours are benign. However, others feel that some of these tumours have the potential to develop into renal cell carcinoma. There are no diagnostic tests that can confirm if a benign tumour has the potential to become cancerous. Benign tumours are sometimes found along with renal cell carcinoma when a removed kidney is examined by a pathologist. For these reasons, benign kidney tumours are treated like malignant tumours. In this case we have observed a male cadaver with a large tumour in the left kidney during our routine dissections of undergraduates .

  12. 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.

  13. 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.

  14. 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.

  15. Loss of sensory attenuation in patients with functional (psychogenic) movement disorders.

    Science.gov (United States)

    Pareés, Isabel; Brown, Harriet; Nuruki, Atsuo; Adams, Rick A; Davare, Marco; Bhatia, Kailash P; Friston, Karl; Edwards, Mark J

    2014-11-01

    Functional movement disorders require attention to manifest yet patients report the abnormal movement to be out of their control. In this study we explore the phenomenon of sensory attenuation, a measure of the sense of agency for movement, in this group of patients by using a force matching task. Fourteen patients and 14 healthy control subjects were presented with forces varying from 1 to 3 N on the index finger of their left hand. Participants were required to match these forces; either by pressing directly on their own finger or by operating a robot that pressed on their finger. As expected, we found that healthy control subjects consistently overestimated the force required when pressing directly on their own finger than when operating a robot. However, patients did not, indicating a significant loss of sensory attenuation in this group of patients. These data are important because they demonstrate that a fundamental component of normal voluntary movement is impaired in patients with functional movement disorders. The loss of sensory attenuation has been correlated with the loss of sense of agency, and may help to explain why patients report that they do not experience the abnormal movement as voluntary.

  16. Oleanolic acid attenuates liver ischemia reper-fusion injury by HO-1/Sesn2 signaling pathway

    Institute of Scientific and Technical Information of China (English)

    Bao-Bin Hao; Xiong-Xiong Pan; Ye Fan; Ling Lu; Xiao-Feng Qian; Xue-Hao Wang; Feng Zhang; Jian-Hua Rao

    2016-01-01

    BACKGROUND: Ischemia reperfusion injury (IRI) is unavoid-able in liver transplantation and hepatectomy. The present study aimed to explore the possible mechanism and the effect of oleanolic acid (OA) in hepatic IRI. METHODS: Mice were randomly divided into 6 groups based on different treatment. IRI model: The hepatic artery, portal vein, and bile duct to the left and median liver lobes (70% of the liver) were occluded with an atraumatic bulldog clamp for 90 minutes and then the clamp was removed for reperfusion. The mice were sacriifced 6 hours after reperfusion, and blood and liver tissues were collected. Liver injury was evaluated by biochemical and histopathologic examinations. The expressions of Sesn2, PI3K, Akt and heme oxygenase-1 (HO-1) were mea-sured with quantitative real-time RT-PCR and Western blotting. RESULTS: The serum aminotransferases level and scores of he-patic histology were increased after reperfusion. The increase was attenuated by pretreatment with OA (P CONCLUSIONS: Our results demonstrate that OA can attenu-ate hepatic IRI. The protective mechanism may be related to the OA-induced HO-1/Sesn2 signaling pathway.

  17. 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.

  18. Attenuation of seismic waves in Central Egypt

    Directory of Open Access Journals (Sweden)

    Mamdouh Abbas Morsy

    2013-06-01

    Full Text Available Attenuation of seismic waves in central Egypt had never been studied before. The results of the research on the seismic attenuation are based upon the information collected by the seismological network from 1998 to 2011. 855 earthquakes were selected from the Egyptian seismological catalog, with their epicenter distances between 15 and 150 km, their magnitudes ranging from 2 and 4.1 and focal depths reaching up to 30 km. The first systematic study of attenuation derived from the P-, S- and coda wave in the frequency range 1–24 Hz is presented. In the interpretation of the results both single and multiple scattering in a half space are considered. The single scattering model proposed by Sato (1977 was used. Two methods, the coda (Qc and the Multiple Lapse Time Window (MLTW method are used. The aim of this study is to validate these interpretations in the region and to try to identify the effects of attenuation due to intrinsic (Qi and scattering attenuation (Qsc. The mean Qc value calculated was Qc = (39 ± 1f1.0±0.009. The average Qc at 1.5 Hz is (53 ± 6 and Qc = (900 ± 195 at 24 Hz with Qo ranging between 23 and 107, where η ranging between 0.9 and 1.3. The quality factor (Q was estimated from spectra of P- and S-waves by applying a spectral ratio technique. The results show variations in Qp and QS as a function of frequency, according to the power law Q = 56η1.1. The seismic albedo is 0.7 at all stations and it mean that the earthquake activity is due to tectonic origin. The attenuation and frequency dependency for different paths and the correlation of the results with the geotectonic of the region are presented. The Qc values were calculated and correlated with the geology and tectonics of the area. The relatively low Qo and the high frequency dependency agree with the values of a region characterized by a low tectonic activity and vise versa.

  19. Relationship of left heart size and left ventricular mass with exercise capacity in chronic heart failure

    Institute of Scientific and Technical Information of China (English)

    SHEN Yu-qin; WANG Le-min; CHE Lin; SONG Hao-ming; ZHANG Qi-ping

    2011-01-01

    Background Impaired exercise capacity is one of the most common clinical manifestations in patients with chronic heart failure (CHF). The severity of reduced exercise capacity is an indicator of disease prognosis. The aim of the current study was to investigate the association between left heart size and mass with exercise capacity.Methods A total of 74 patients were enrolled in the study, with 37 having congestive heart failure (left ventricular ejection fraction (LVEF) <0.45) and the other 37 with coronary heart disease (by coronary angiography) serving as the control group (LVEF >0.55). Echocardiography and cardiopulmonary exercise test were performed. The multiply linear regression model was used to evaluate the association between echocardiogrphic indices and exercise capacities.Results The study showed that left ventricular end diastolic / systolic diameter (LVEDD/LVESD), left atrial diameter (LAD) and left ventricular mass index (LVMI) were significantly enlarged in patients with chronic heart failure compared with controls (P <0.01). The VO2AT, Peak VO2, Load AT, and Load Peak in chronic heart failure patients were also significantly reduced compared with controls (P <0.05), VE/VCO2 slope was increased in patients with chronic heart failure (P <0.01). Multivariate linear regression analysis indicated that the patients' exercise capacity was significantly associated with the left heart size and mass, however, the direction and/or strength of the associations sometimes varied in chronic heart failure patients and controls. Load AT correlated negatively with LVEDD in chronic heart failure patients (P=0.012), while Load AT correlated positively with LVEDD in control patients (P=0.006). VE/VCO2 slope correlated positively with LAD (B=0.477, P <0.0001) in chronic heart failure patients, while the VE/VCO2 slope correlated negatively with LAD in control patients (P=0.009).Conclusion The study indicates that the size of LVEDD and LAD are important

  20. 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.

  1. On the excess attenuation of sound in the atmosphere

    Science.gov (United States)

    Deloach, R.

    1975-01-01

    The attenuation suffered by an acoustic plane wave propagating from an elevated source to the ground, in excess of absorption losses, was studied. Reported discrepancies between attenuation measurements made in the field and theories which only account for absorption losses are discussed. It was concluded that the scattering of sound by turbulence results in a nonnegligible contribution to the total attenuation.

  2. 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.

  3. Left ventricular pressure-volume diagrams and end-systolic pressure-volume relations in human beings.

    Science.gov (United States)

    McKay, R G; Aroesty, J M; Heller, G V; Royal, H; Parker, J A; Silverman, K J; Kolodny, G M; Grossman, W

    1984-02-01

    Assessment of left ventricular pressure-volume relations serially in response to altered loading conditions and heart rate has been difficult to achieve with contrast ventriculography. Accordingly, to study changing pressure-volume relations during altered loading and heart rate, left ventricular pressure and radionuclide absolute volume curves (obtained using a counts-based method with attenuation factor corrections) were recorded in 20 patients. Ventricular pressure and radionuclide volume curves were digitized and synchronized to end-diastole, and pressure-volume plots were subsequently constructed from 32 pressure-volume coordinates throughout the cardiac cycle. In all patients, the correlation between radionuclide absolute volumes and angiographic ventricular volumes was r = 0.92. In 10 patients in whom both radionuclide and angiographic pressure-volume diagrams were constructed, the agreement between the two methods was excellent. With this method, end-systolic pressure-volume relations were examined during altered left ventricular loading conditions, pacing-induced incremental increases in heart rate and pacing-induced ischemia. Using pharmacologically induced changes in left ventricular loading conditions, the slope and volume intercept of the end-systolic pressure-volume line could be calculated as a means of assessing basal contractility. During pacing-induced tachycardia, the slope and volume intercept of the end-systolic pressure-volume line could be calculated to quantify the Treppe effect and assess negative inotropic changes secondary to ischemia. This study supports the validity of using serial recordings of left ventricular pressure and radionuclide volumes to assess left ventricular pressure-volume relations, and indicates that this approach may be useful in the analysis of end-systolic pressure-volume relations in patients.

  4. Left ventricular pressure-volume diagrams and end-systolic pressure-volume relations in human beings

    Energy Technology Data Exchange (ETDEWEB)

    McKay, R.G.; Aroesty, J.M.; Heller, G.V.; Royal, H.; Parker, J.A.; Silverman, K.J.; Kolodny, G.M.; Grossman, W.

    1984-02-01

    Assessment of left ventricular pressure-volume relations serially in response to altered loading conditions and heart rate has been difficult to achieve with contrast ventriculography. Accordingly, to study changing pressure-volume relations during altered loading and heart rate, left ventricular pressure and radionuclide absolute volume curves (obtained using a counts-based method with attenuation factor corrections) were recorded in 20 patients. Ventricular pressure and radionuclide volume curves were digitized and synchronized to end-diastole, and pressure-volume plots were subsequently constructed from 32 pressure-volume coordinates throughout the cardiac cycle. In all patients, the correlation between radionuclide absolute volumes and angiographic ventricular volumes was r . 0.92. In 10 patients in whom both radionuclide and angiographic pressure-volume diagrams were constructed, the agreement between the two methods was excellent. With this method, end-systolic pressure-volume relations were examined during altered left ventricular loading conditions, pacing-induced incremental increases in heart rate and pacing-induced ischemia. Using pharmacologically induced changes in left ventricular loading conditions, the slope and volume intercept of the end-systolic pressure-volume line could be calculated as a means of assessing basal contractility. During pacing-induced tachycardia, the slope and volume intercept of the end-systolic pressure-volume line could be calculated to quantify the Treppe effect and assess negative inotropic changes secondary to ischemia. This study supports the validity of using serial recordings of left ventricular pressure and radionuclide volumes to assess left ventricular pressure-volume relations, and indicates that this approach may be useful in the analysis of end-systolic pressure-volume relations in patients.

  5. Are there right hemisphere contributions to visually-guided movement? Manipulating left hand reaction time advantages in dextrals

    Directory of Open Access Journals (Sweden)

    David Peter Carey

    2015-08-01

    Full Text Available Many studies have argued for distinct but complementary contributions from each hemisphere in the control of movements to visual targets. Investigators have attempted to extend observations from patients with unilateral left- and right –hemisphere damage, to those using neurologically-intact participants, by assuming that each hand has privileged access to the contralateral hemisphere. Previous attempts to illustrate right hemispheric contributions to the control of aiming have focussed on increasing the spatial demands of an aiming task, to attenuate the typical right hand advantages, to try to enhance a left hand reaction time advantage in right-handed participants. These early attempts have not been successful. The present study circumnavigates some of the theoretical and methodological difficulties of some of the earlier experiments, by using three different tasks linked to specialised functions of the right hemisphere: bisecting, the gap effect, and visuospatial localisation. None of these tasks were effective in reducing the magnitude of left hand reaction time advantages in right handers. Results are discussed in terms of alternatives to right hemispheric functional explanations of the effect, the one dimensional nature of our target arrays, power and precision given the size of the left hand RT effect, and the utility of examining the proportions of participants who show these effects, rather than exclusive reliance on measures of central tendency and their associated null hypothesis significance tests.

  6. Are there right hemisphere contributions to visually-guided movement? Manipulating left hand reaction time advantages in dextrals.

    Science.gov (United States)

    Carey, David P; Otto-de Haart, E Grace; Buckingham, Gavin; Dijkerman, H Chris; Hargreaves, Eric L; Goodale, Melvyn A

    2015-01-01

    Many studies have argued for distinct but complementary contributions from each hemisphere in the control of movements to visual targets. Investigators have attempted to extend observations from patients with unilateral left- and right-hemisphere damage, to those using neurologically-intact participants, by assuming that each hand has privileged access to the contralateral hemisphere. Previous attempts to illustrate right hemispheric contributions to the control of aiming have focussed on increasing the spatial demands of an aiming task, to attenuate the typical right hand advantages, to try to enhance a left hand reaction time advantage in right-handed participants. These early attempts have not been successful. The present study circumnavigates some of the theoretical and methodological difficulties of some of the earlier experiments, by using three different tasks linked directly to specialized functions of the right hemisphere: bisecting, the gap effect, and visuospatial localization. None of these tasks were effective in reducing the magnitude of left hand reaction time advantages in right handers. Results are discussed in terms of alternatives to right hemispheric functional explanations of the effect, the one-dimensional nature of our target arrays, power and precision given the size of the left hand RT effect, and the utility of examining the proportions of participants who show these effects, rather than exclusive reliance on measures of central tendency and their associated null hypothesis significance tests.

  7. The effects of candesartan on left ventricular hypertrophy and function in nonobstructive hypertrophic cardiomyopathy: a pilot, randomized study.

    Science.gov (United States)

    Penicka, Martin; Gregor, Pavel; Kerekes, Roman; Marek, Dan; Curila, Karol; Krupicka, Jiri

    2009-01-01

    Hypertrophic cardiomyopathy is caused by mutations in the genes that encode sarcomeric proteins and is primarily characterized by unexplained left ventricular hypertrophy, impaired cardiac function, reduced exercise tolerance, and a relatively high incidence of sudden cardiac death, especially in the young. The extent of left ventricular hypertrophy is one of the major determinants of disease prognosis. Angiotensin II has trophic effects on the heart and plays an important role in the development of myocardial hypertrophy. Here in a double-blind, placebo-controlled, randomized study, we show that the long-term administration of the angiotensin II type 1 receptor antagonist candesartan in patients with hypertrophic cardiomyopathy was associated with the significant regression of left ventricular hypertrophy, improvement of left ventricular function, and exercise tolerance. The magnitude of the treatment effect was dependent on specific sarcomeric protein gene mutations that had the greatest responses on the carriers of ss-myosin heavy chain and cardiac myosin binding protein C gene mutations. These data indicate that modulating the role of angiotensin II in the development of hypertrophy is specific with respect to both the affected sarcomeric protein gene and the affected codon within that gene. Thus, angiotensin II type 1 receptor blockade has the potential to attenuate myocardial hypertrophy and may, therefore, provide a new treatment option to prevent sudden cardiac death in patients with hypertrophic cardiomyopathy.

  8. Low Intensity Physical Exercise Attenuates Cardiac Remodeling and Myocardial Oxidative Stress and Dysfunction in Diabetic Rats

    Directory of Open Access Journals (Sweden)

    C. Gimenes

    2015-01-01

    Full Text Available We evaluated the effects of a low intensity aerobic exercise protocol on cardiac remodeling and myocardial function in diabetic rats. Wistar rats were assigned into four groups: sedentary control (C-Sed, exercised control (C-Ex, sedentary diabetes (DM-Sed, and exercised diabetes (DM-Ex. Diabetes was induced by intraperitoneal injection of streptozotocin. Rats exercised for 9 weeks in treadmill at 11 m/min, 18 min/day. Myocardial function was evaluated in left ventricular (LV papillary muscles and oxidative stress in LV tissue. Statistical analysis was given by ANOVA or Kruskal-Wallis. Echocardiogram showed diabetic groups with higher LV diastolic diameter-to-body weight ratio and lower posterior wall shortening velocity than controls. Left atrium diameter was lower in DM-Ex than DM-Sed (C-Sed: 5.73±0.49; C-Ex: 5.67±0.53; DM-Sed: 6.41±0.54; DM-Ex: 5.81±0.50 mm; P<0.05 DM-Sed vs C-Sed and DM-Ex. Papillary muscle function was depressed in DM-Sed compared to C-Sed. Exercise attenuated this change in DM-Ex. Lipid hydroperoxide concentration was higher in DM-Sed than C-Sed and DM-Ex. Catalase and superoxide dismutase activities were lower in diabetics than controls and higher in DM-Ex than DM-Sed. Glutathione peroxidase activity was lower in DM-Sed than C-Sed and DM-Ex. Conclusion. Low intensity exercise attenuates left atrium dilation and myocardial oxidative stress and dysfunction in type 1 diabetic rats.

  9. 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.

  10. Attenuated partial internal reflection infrared spectroscopy.

    Science.gov (United States)

    Zhang, Zhenfeng; Ewing, George E

    2002-06-01

    A new method for the spectroscopic study of absorbing films is proposed. In contrast to the well-established methods that take advantage of the attenuation of total internal reflection (ATR) to obtain spectra, we intentionally arrange the optics to permit partial internal reflection from the sampling prism face. Attenuated partial internal reflection (APR) spectroscopy is introduced through theoretical calculations and experimental demonstrations. The calculated APR spectra in the infrared region were generated from the Fresnel and Airy equations. Experimentally, APR spectra of water films on a NaCl prism were obtained. APR is more sensitive than ATR, and can easily distinguish water films at the monolayer level (310 pm). The determination of film thickness from interference fringes in APR spectra is also illustrated. It is shown that APR can be used for film thickness measurements that can span 6 orders of magnitude. The limitations of APR are also discussed.

  11. 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.

  12. Attenuated psychosis syndrome: benefits of explicit recognition

    Science.gov (United States)

    SCHIFFMAN, Jason; CARPENTER, William T

    2015-01-01

    Summary Given the unique characteristics of people who meet criteria for attenuated psychosis syndrome (APS) and the growing literature on the clinical benefits of providing services to individuals who meet these criteria, the APS diagnosis serves an important, and previously missing, role in psychiatry. The promotion of the APS diagnosis should help reduce the over-diagnosis and over-treatment of individuals with prodromal psychotic conditions and it should also encourage expanded training about attenuated psychosis among clinicians who primarily provide services to youth (a primary group who are diagnosed with APS). Only some of the individuals with APS subsequently develop psychosis, but all have existing clinical needs – regardless of subsequent conversion. The formal recognition of APS in DSM-5 will facilitate the research needed to identify and meet those needs. PMID:25852257

  13. 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.

  14. Evaluation of left renal vein entrapment using multidetector computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Poyraz, Ahmet K.; Onur, Mehmet R. [Dept. of Radiology, Firat Univ. School of Medicine, Elazig (Turkey)], e-mail: akursadpoyraz@yahoo.com.tr; Firdolas, Fatih [Dept. of Urology, Firat Univ. School of Medicine, Elazig (Turkey); Kocakoc, Ercan [Dept. of Radiology, Bezmialem Vakif Univ., School of Medicine, Istanbul (Turkey)

    2013-03-15

    Background: Nutcracker syndrome, also called left renal vein entrapment syndrome, is a cause of non-glomerular hematuria with difficulties in diagnosis. Multidetector computed tomography (MDCT) is a powerful tool to prevent unnecessary diagnostic procedures. Purpose: To retrospectively determine the prevalence of nutcracker phenomenon and nutcracker syndrome seen in MDCT in consecutive patients. Material and Methods: The institutional review board approved the study and waived the requirement for informed consent. Abdominal contrast-enhanced MDCT scans were reviewed from 1000 consecutive patients. MDCT scan assessment included renal vein diameter measurements and evaluation for the presence of anterior or posterior left renal vein entrapment. Electronic medical records and urine analysis reports of patients with left renal vein entrapment were reviewed. Student's t test was used to assess differences in renal vein diameter in patients with left renal vein entrapment. Results: Left renal vein entrapment was observed in 10.9% (109), retroaortic left renal vein in 6.5% (65), entrapment of left renal vein between superior mesenteric artery and aorta in 4.1% (41), and circumaortic left renal vein in 0.3% (3) of patients. Mean diameters of right (8.8 {+-} 1.9 mm) and unentrapped left (8.9 {+-} 1.8 mm) renal veins were not significantly different (P = 0.1). The mean diameter of anterior entrapped left renal veins (10.3 {+-} 2 mm) was significantly greater (P = 0.04) than contralateral renal veins (8.6 {+-} 2.1 mm) in their widest portion. In 8.8% of patients with the left renal vein entrapment, urine analysis showed isomorphic hematuria or proteinuria with no other known cause. Varicocele and pelvic congestion were seen in 5.5% of patients with the left renal vein entrapment. Conclusion: Left renal vein entrapment is not a rare entity and renal nutcracker phenomenon might be underdiagnosed.

  15. 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.

  16. 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.

  17. Molecular Characterization of Attenuated Junin Virus Variants.

    Science.gov (United States)

    1992-07-14

    No. DAMD17-89-Z-9024 Area de Quimica Biologica y Biologia Molecular Facultad de Ciencias Exactas Universidad Nacional de La Plata Calles 47 y 115, 1900...MONITORING ORGANIZATION Area de Quimica Biologica (If applicable) y Biologia Molecular I 6c. ADDRESS (City, State, and ZIPCode) 7b. ADDRESS (City, State...AD-A260 128 AD____ MOLECULAR CHARACTERIZATION OF ATTENUATED JUNIN VIRUS VARIANTS FINAL REPORT VICTOR ROMANOWSKI PABLO D. GHIRINGHELLI CESAR G

  18. 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.

  19. 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.

  20. 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.

  1. A neonate with left pulmonary artery thrombosis and left lung hypoplasia: a case report

    Directory of Open Access Journals (Sweden)

    ElHassan Nahed O

    2010-08-01

    Full Text Available Abstract Introduction Spontaneous intrauterine arterial thrombosis and congenital pulmonary hypoplasia are rare conditions and have not been reported to occur together. The literature rather includes two reports of babies with neonatal pulmonary artery occlusion and post-infarction cysts of the lungs. Case presentation We report a case of a live Caucasian male newborn with left lung hypoplasia that occurred in association with left pulmonary artery thrombosis. Despite a critical neonatal course, including extracorporeal membrane oxygenation, this infant is alive and well at 18 months of age without any neurodevelopmental sequelae or reactive airway disease. Conclusion This association suggests the possibility of an intrauterine vascular event between the fifth and eighth weeks of gestation during early pulmonary artery and lung development.

  2. 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.

  3. Effect of zinc supplements in the attenuated cardioprotective effect of ischemic preconditioning in hyperlipidemic rat heart.

    Science.gov (United States)

    Kansal, Sunil Kumar; Jyoti, Uma; Sharma, Samridhi; Kaura, Arun; Deshmukh, Rahul; Goyal, Sandeep

    2015-06-01

    Hyperlipidemia is regarded as independent risk factor in the development of ischemic heart disease, and it can increase the myocardial susceptibility to ischemia-/reperfusion (I/R)-induced injury. Hyperlipidemia attenuates the cardioprotective response of ischemic preconditioning (IPC). The present study investigated the effect of zinc supplements in the attenuated cardioprotective effect of ischemic preconditioning in hyperlipidemic rat hearts. Hyperlipidemia was induced in rat by feeding high-fat diet (HFD) for 6 weeks then the serum lipid profile was observed. In experiment, the isolated Langendorff rat heart preparation was subjected to 4 cycles of ischemic preconditioning (IPC), then 30 min of ischemia followed by 120 min of reperfusion. Myocardial infarct size was elaborated morphologically by triphenyltetrazolium chloride (TTC) staining and biochemically by lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) release from coronary effluent and left ventricular collagen content. However, the effect of zinc supplement, i.e., zinc pyrithione (10 μM) perfused during reperfusion for 120 min, significantly abrogated the attenuated cardioprotective effect of ischemic preconditioning in hyperlipidemic rat heart whereas administration of chelator of this zinc ionophore, i.e., N,N,N',N'-tetrakis(2-pyridylmethyl)ethylene diamine (TPEN; 10 μM), perfused during reperfusion 2 min before the perfusion of zinc pyrithione abrogated the cardioprotective effect of zinc supplement during experiment in hyperlipidemic rat heart. Thus, the administration of zinc supplements limits the infarct size, LDH, and CK-MB and enhanced the collagen level which suggests that the attenuated cardioprotective effect of IPC in hyperlipidemic rat is due to zinc loss during reperfusion caused by ischemia/reperfusion.

  4. 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.

  5. Fourier coefficient description of left ventricular shape.

    Science.gov (United States)

    Round, W H; Bates, R H; Ikram, H

    1991-12-01

    A method of quantifying the shape of the left ventricle of the heart as seen in 2D echocardiograms was developed. It is based on describing the shape in terms of the coefficients a fifth-order trigonometric Fourier series. Such a series has eleven Fourier coefficients which is too large a number for clinical application so pairs of coefficients are combined to give six coefficients (alpha 0, alpha 1, ... , alpha 5). A trial was conducted to test the ability of the coefficient description to classify subjects as having normal right ventricles or ventricles with an apical abnormality. The tests showed that one of the coefficients (alpha 2) was higher for the subjects with an apical abnormality and that this difference increased with exercise. This is as was expected. However, it was found to be difficult to get a reliable estimate of alpha 2 from a single scan of a patient and that it is therefore probably necessary to average data from several scans to obtain a reliable alpha 2 value for a single patient.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. Hemodynamic forces in a model left ventricle

    Science.gov (United States)

    Domenichini, Federico; Pedrizzetti, Gianni

    2016-12-01

    Intraventricular pressure gradients were clinically demonstrated to represent one useful indicator of the left ventricle (LV) function during the development of heart failure. We analyze the fluid dynamics inside a model LV to improve the understanding of the development of hemodynamic forces (i.e., mean pressure gradient) in normal conditions and their modification in the presence of alterations of LV tissue motion. To this aim, the problem is solved numerically and the global force exchanged between blood flow and LV boundaries is computed by volume integration. We also introduce a simplified analytical model, based on global conservation laws, to estimate hemodynamic forces from the knowledge of LV tissue information commonly available in cardiac imaging. Numerical results show that the normal intraventricular gradients feature a deep brief suction at early diastolic filling and a persistent thrust during systolic ejection. In presence of abnormalities of the wall motion, the loss of time synchrony is more relevant than the loss of spatial uniformity in modifying the normal pressure gradient spatiotemporal pattern. The main findings are reproduced in the integral model, which represents a possible easy approach for integrating fluid dynamics evaluations in the clinical examination.

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. Crab scars reveal survival advantage of left-handed snails

    OpenAIRE

    Dietl, Gregory P.; Hendricks, Jonathan R.

    2006-01-01

    Biological asymmetries are important elements of the structure and function of many living organisms. Using the Plio–Pleistocene fossil record of crab predation on morphologically similar pairs of right- and left-handed snail species, we show here for the first time, contrary to traditional wisdom, that rare left-handed coiling promotes survival from attacks by right-handed crabs. This frequency-dependent result influences the balance of selection processes that maintain left-handedness at th...

  19. On left (θ,ϕ-derivations in BCI-algebras

    Directory of Open Access Journals (Sweden)

    G. Muhiuddin

    2014-07-01

    Full Text Available The notion of (regular left (θ,ϕ-derivations of a BCI-algebra is introduced, some useful examples are discussed, and related properties are investigated. Conditions for a left (θ,ϕ-derivation to be regular are provided. The concepts of a d(θ,ϕ-invariant left (θ,ϕ-derivation and θ-ideal are introduced, and their relations are discussed. Furthermore, some more interesting results are established.

  20. 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.

  1. Anatomical variation of the origin of the left vertebral artery

    OpenAIRE

    Patasi B; Yeung A; Goodwin S; Jalali A

    2009-01-01

    This paper presents and describes the anatomical variation of the left vertebral artery originating from the arch of aorta as a case report. This variation was found in one of the cadavers at the Division of Clinical and Functional Anatomy, Faculty of Medicine, University of Ottawa. During routine dissection of a male cadaver, in the superior mediastinum and the neck we observed an atypical origin of the left vertebral artery. Atypical origin was compared to the typical origin of the left ver...

  2. [Vertigo induced by noise or pressure to the left ear].

    Science.gov (United States)

    Seidel, D U; Dülks, A; Remmert, S

    2011-06-01

    A 49-year-old male patient presented with recently acquired vertigo induced by noise or pressure to the left ear. With appropriate stimulation, oscillopsia with a rotatory component could be reproduced in videooculography. Cervical vestibular evoked myogenic potentials (VEMP) showed increased amplitudes and a lowered threshold on the left side. CT of the petrous bone showed a bony dehiscence of the left superior semicircular canal. Conservative therapy was initiated as a first step.

  3. Intravascular ultrasound for angiographically indeterminant left main coronary artery disease.

    Science.gov (United States)

    Parashara, D K; Jacobs, L E; Ledley, G S; Yazdanfar, S; Oline, J; Kotler, M N

    1994-01-01

    The precise diagnosis of the presence of significant left main coronary artery disease has profound prognostic and therapeutic implications. Coronary cineangiography has shown to be imprecise and inaccurate to determine the percent stenosis of the left main coronary artery. We report a case with significant left main coronary artery disease in whom coronary cineangiography was in discordance with the clinical data and intravascular ultrasonography. Based on the intravascular ultrasound findings, the patient underwent coronary artery bypass graft surgery. Therefore, the intravascular ultrasonography may be the procedure of choice for assessing indeterminant left main coronary artery lesions by coronary angiography.

  4. 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.

  5. Symptomatic Type IV Dual Left Anterior Descending Coronary Artery

    Directory of Open Access Journals (Sweden)

    Kyriacos Papadopoulos MD

    2016-12-01

    Full Text Available Dual left anterior descending coronary artery is a rare congenital anomaly with 4 subtypes. Double left anterior descending coronary artery originating from the left main stem and the right coronary artery (type IV dual left anterior descending artery has been reported to occur in 0.01% to 0.7% of patients undergoing cardiac catheterization. We report a case of a 49-year-old woman who was found to have this anomaly during coronary angiography. The patient had been complaining of chest pain that mimics angina pectoris and exercise tolerance test was positive for myocardial ischemia.

  6. Postconditioning attenuates no-reflow in STEMI patients.

    Science.gov (United States)

    Mewton, Nathan; Thibault, Hélène; Roubille, François; Lairez, Olivier; Rioufol, Gilles; Sportouch, Catherine; Sanchez, Ingrid; Bergerot, Cyrille; Cung, Thien Tri; Finet, Gérard; Angoulvant, Denis; Revel, Didier; Bonnefoy-Cudraz, Eric; Elbaz, Meyer; Piot, Christophe; Sahraoui, Inesse; Croisille, Pierre; Ovize, Michel

    2013-11-01

    After acute myocardial infarction, the presence of no-reflow (or microvascular obstruction: MVO) has been associated with adverse left ventricular (LV) remodeling and worse clinical outcome. This study examined the effects of mechanical ischemic postconditioning on early and late MVO size in acute ST-elevation myocardial infarction (STEMI) patients. Fifty patients undergoing primary coronary angioplasty for a first STEMI with TIMI grade flow 0-1 and no collaterals were randomized to ischemic postconditioning (PC) (n = 25) or control (n = 25) groups. Ischemic PC consisted in the application of four consecutive cycles of a 1-min balloon occlusion, each followed by a 1-min deflation at the onset of reperfusion. Early (3 min post-contrast) and late (10 min post-contrast) MVO size were assessed by contrast-enhanced cardiac-MRI within 96 h after reperfusion. PC was associated with smaller early and late MVO size (3.9 ± 4.8 in PC versus 7.8 ± 6.6% of LV in controls for early MVO, P = 0.02; and 1.8 ± 3.1 in PC versus 4.1 ± 3.9% of LV in controls for late MVO; P = 0.01). This significant reduction was persistent after adjustment for thrombus aspiration, which neither had any significant effect on infarct size, nor on early or late MVO (P = NS for all). Attenuation of MVO was associated to infarct size reduction. Mechanical postconditioning significantly reduces MVO in patients with acute STEMI treated with primary angioplasty.

  7. Early left-hemispheric dysfunction of face processing in congenital prosopagnosia: an MEG study.

    Directory of Open Access Journals (Sweden)

    Christian Dobel

    Full Text Available BACKGROUND: Congenital prosopagnosia is a severe face perception impairment which is not acquired by a brain lesion and is presumably present from birth. It manifests mostly by an inability to recognise familiar persons. Electrophysiological research has demonstrated the relevance to face processing of a negative deflection peaking around 170 ms, labelled accordingly as N170 in the electroencephalogram (EEG and M170 in magnetoencephalography (MEG. The M170 was shown to be sensitive to the inversion of faces and to familiarity--two factors that are assumed to be crucial for congenital prosopagnosia. In order to locate the cognitive dysfunction and its neural correlates, we investigated the time course of neural activity in response to these manipulations. METHODOLOGY: Seven individuals with congenital prosopagnosia and seven matched controls participated in the experiment. To explore brain activity with high accuracy in time, we recorded evoked magnetic fields (275 channel whole head MEG while participants were looking at faces differing in familiarity (famous vs. unknown and orientation (upright vs. inverted. The underlying neural sources were estimated by means of the least square minimum-norm-estimation (L2-MNE approach. PRINCIPAL FINDINGS: The behavioural data corroborate earlier findings on impaired configural processing in congenital prosopagnosia. For the M170, the overall results replicated earlier findings, with larger occipito-temporal brain responses to inverted than upright faces, and more right- than left-hemispheric activity. Compared to controls, participants with congenital prosopagnosia displayed a general decrease in brain activity, primarily over left occipitotemporal areas. This attenuation did not interact with familiarity or orientation. CONCLUSIONS: The study substantiates the finding of an early involvement of the left hemisphere in symptoms of prosopagnosia. This might be related to an efficient and overused featural

  8. 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

  9. 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.

  10. 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.

  11. Osteopathic treatment in a patient with left-ventricular assist device with left brachialgia: a case report

    Science.gov (United States)

    Bordoni, Bruno; Marelli, Fabiola; Morabito, Bruno; Sacconi, Beatrice

    2017-01-01

    This study deals with an osteopathic approach used for a patient with left-ventricular assist device (L-VAD) affected by left brachialgia. Clinical examination revealed the presence of thoracic outlet syndrome and pectoralis minor syndrome, with compression of the left proximal ulnar nerve, related to the surgical sternotomy performed. The osteopathic techniques used can be classified as indirect and direct, addressed to the pectoralis minor and the first left rib, respectively. To our knowledge, this is the first text in literature with an osteopathic treatment in a patient with L-VAD. PMID:28144166

  12. 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.

  13. 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.

  14. Measuring the attenuation length in liquid scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Hellgartner, Dominikus; Oberauer, Lothar; Prummer, Sabrina; Sawatzki, Julia; Zimmer, Vincenz [Technische Universitaet Muenchen, Physik Departement E15, James Franck Strasse, 85748 Garching (Germany); Ulrich, Andreas [Technische Universitaet Muenchen, Physik Departement E12, James Franck Strasse, 85748 Garching (Germany)

    2015-07-01

    The next generation of liquid scintillator detectors like the proposed LENA detector or the planned JUNO detector will feature diameters of order 30 m. Due to this vast size, the optical quality of the scintillator is of crucial importance. To determine the attenuation length of liquid scintillators, an experiment with a 5 m long measurement section was set-up in the underground laboratory in Garching. The current set-up of the experiment is presented along with a discussion of the results of the first measurements. Additionally, there is an outlook towards possible upgrades of the experiment in the future.

  15. Laparoscopic features and repair of a combined left Spigelian hernia and left Morgagni diaphragmatic hernia.

    Science.gov (United States)

    Chamary, S L; Chamary, V L

    2015-03-01

    Both Spigelian and Morgagni hernias cause serious morbidity so early diagnosis and timely treatment are necessary. These two types of hernia are more commonly found on the right side of patients. They are rare individually in adults and even rarer in combination. So far, an association between the two hernias has only been reported on the right. We describe the first case of a Spigelian hernia and a Morgagni hernia in a 62-year-old woman, both occurring on the left side. Our accompanying video describes several laparoscopic features that will help lead to early detection and diagnosis.

  16. Why are some people left-handed? An evolutionary perspective.

    Science.gov (United States)

    Llaurens, V; Raymond, M; Faurie, C

    2009-04-12

    Since prehistoric times, left-handed individuals have been ubiquitous in human populations, exhibiting geographical frequency variations. Evolutionary explanations have been proposed for the persistence of the handedness polymorphism. Left-handedness could be favoured by negative frequency-dependent selection. Data have suggested that left-handedness, as the rare hand preference, could represent an important strategic advantage in fighting interactions. However, the fact that left-handedness occurs at a low frequency indicates that some evolutionary costs could be associated with left-handedness. Overall, the evolutionary dynamics of this polymorphism are not fully understood. Here, we review the abundant literature available regarding the possible mechanisms and consequences of left-handedness. We point out that hand preference is heritable, and report how hand preference is influenced by genetic, hormonal, developmental and cultural factors. We review the available information on potential fitness costs and benefits acting as selective forces on the proportion of left-handers. Thus, evolutionary perspectives on the persistence of this polymorphism in humans are gathered for the first time, highlighting the necessity for an assessment of fitness differences between right- and left-handers.

  17. Why are there (almost) no left-handers in China?

    Science.gov (United States)

    Kushner, Howard I

    2013-06-01

    Surveys of Chinese students since the 1980s report that less than 1% are left-handed. This is an extraordinarily low number given the generally accepted view that between 10 and 12% of humans are left-handed. Are there actually very few left-handers in China and, if so, why? A number of sometimes overlapping reasons have shaped Chinese attitudes toward left-handedness. Some of these reflect the transcendent human reactions to biological laterality. Others have been shaped by Chinese historical and cultural experience. What is true in China can be identified in other societies: attitudes and practices toward left-handers have been and continue to be shaped by over-determined forces, which at the same time transcend specific cultures, while they respond to historical and cultural pressures. Like the Chinese, many North and East African peoples attempt to 'cure' left-handedness by a combination of restraints and severe punishments. Religion has often reinforced these practices. In China, we can see how a combination of traditional values and practical considerations seems to have merged to reduce both the actual and reported prevalence of left-handedness. When we add in the population of India, and much of the remaining Islamic world, we can conclude that for two-thirds of the world's population, being born left-handed exposes one to discrimination and stigma.

  18. 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.

  19. Pseudoaneurysm of the left atrium following infective endocarditis

    Science.gov (United States)

    Manuel, Devi A; Sahayo, Bino John; Thomson, Viji Samuel; Jose, Jacob

    2017-01-01

    Transthoracic echocardiogram of a 3-year-old child showed a hypoechoic cavity in the posterior wall of the left atrium communicating with the left ventricle through an orifice in the mitral annulus, suggestive of pseudoaneurysm (Ps), probably the result of infective endocarditis. Three-dimensional echocardiography was helpful to confirm the diagnosis and assess the anatomical relationship of the Ps. PMID:28163437

  20. 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.

  1. 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.

  2. 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.

  3. Early changes in left atrial volume after acute myocardial infarction

    DEFF Research Database (Denmark)

    Bakkestrom, R.; Andersen, Mads J; Ersboll, M.

    2016-01-01

    Background: Dilatation of left atrium (LA) reflects chronic LA pressure or volume overload that possesses considerable prognostic information. Little is known regarding the interaction between LA remodeling after acute myocardial infarction (MI) and left atrial pressure at rest and during exercise...

  4. The organisational and ideological development of Green Left

    NARCIS (Netherlands)

    Lucardie, Anthonie; Voerman, Gerrit; Botella, Joan; Ramiro, Luis

    2003-01-01

    In 1991 the Communist Party of the Netherlands (CPN) dissolved itself into the new organisation GreenLeft, founded in 1990. Thus, GreenLeft may be considered the major ‘post-communist party’ in the Netherlands. Yet it is not the only one. A minority of former CPN-members established in 1992 the New

  5. 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...

  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. 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)

  8. 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.

  9. 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.

  10. 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…

  11. Appropriate Education, Juvenile Corrections, and No Child Left Behind

    Science.gov (United States)

    Leone, Peter E.; Cutting, Candace A.

    2004-01-01

    The No Child Left Behind (NCLB) Act of 2001 promotes high-quality educational services for all children and youths, regardless of race, gender, ethnicity, disability, income, or background. Despite the law's laudable goals, one group continues to be left behind: youths who are incarcerated in juvenile correctional facilities. These…

  12. 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...

  13. 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…

  14. 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.

  15. 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…

  16. Left-sided omental torsion with inguinal hernia

    Institute of Scientific and Technical Information of China (English)

    Yasumitsu Hirano; Kaeko Oyama; Hiroshi Nozawa; Takuo Hara; Koichi Nakada; Masahiro Hada; Takeshi Takagi; Makoto Hirano

    2006-01-01

    We report a case of surgically proved left-sided torsion of the greater omentum that caused secondary by untreated inguinal hernia. Case A 36-year-old man presented to our hospital with abdominal pain. He had been diagnosed with a left inguinal hernia, but he had not received any treatments. Contrast-enhanced computed tomography (CT) of the abdomen showed a large fat density mass below the Sigmoid colon and left inguinal hernia with incarcerated fat. Exploratory laparotomy revealed torsion of the greater omentum with small bloody ascites. The greater omentum was twisted into one and a half circles and entered into a left inguinal hernia. An omentectomy with a repair of left inguinal hernia was performed. A resected omentum was submitted for pathological examination, which showed hemorrhagic infarction. Omental torsion is a rare cause of acute abdominal pain but should be included in the differential diagnoses of acute abdomen, especially in patients with untreated inguinal hernia.

  17. 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.

  18. 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.

  19. 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.

  20. Isolated Hypoplasia of Left Pulmonary Artery with Agenesis of Left Lobe of Thyroid: A Case Report.

    Science.gov (United States)

    Khadir, Mohammed Abdul; Narayana, Ganesh; Ramagopal, Ganavi; Nayar, Pradeep G

    2016-12-01

    Isolated Unilateral hypoplasia or agenesis of a branch of pulmonary artery is very rare. It is usually seen associated with congenital heart diseases such as tetralogy of Fallot, atrial septal defect, coarctation of the aorta, right aortic arch, truncus arteriosus, patent ductus arteriosus and pulmonary atresia. It occurs as a result of lack of embryological development of either the left or right sixth aortic arch and has been found to present itself with various clinical manifestations as during childhood it presents as contralateral pulmonary hypertension and in adults as haemoptysis. Early diagnosis and early surgical indication avoids the evolution of pulmonary hypertension to unfavourble state of more severe and progressive degrees and also prevents the development of pulmonary systemic collateral circulation, which is mainly responsible for subsequent haemoptysis in the adulthood. We hereby, report the case of an infant who presented with features of lower respiratory tract infection and later diagnosed as isolated congenital hypoplasia of left pulmonary artery and hence planned for proper follow-up for early surgery thereby preventing complications in the future.

  1. 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.

  2. Left-handedness in professional and amateur tennis.

    Science.gov (United States)

    Loffing, Florian; Hagemann, Norbert; Strauss, Bernd

    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' 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. Surface Wave Attenuation in the Tibetan Plateau from Ambient Noise

    Science.gov (United States)

    2015-08-31

    R. Weaver, and X.N. Yang, Surface wave attenuation in Tibetan Plateau from ambient noise, Monitoring Research Review, Albuquerque, NM, 2012...AFRL-RV-PS- TR-2015-0150 AFRL-RV-PS- TR-2015-0150 SURFACE WAVE ATTENUATION IN THE TIBETAN PLATEAU FROM AMBIENT NOISE University of Illinois at...DATES COVERED (From - To) 01 May 2012 to 31 Aug 2015 4. TITLE AND SUBTITLE Surface Wave Attenuation in the Tibetan Plateau from Ambient Noise 5a

  10. 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

  11. Horseshoe lung associated with left-lung hypoplasia, left pulmonary artery sling and bilateral agenesis of upper lobe bronchi.

    Science.gov (United States)

    Oguz, Berna; Alan, Serdar; Ozcelik, Ugur; Haliloglu, Mithat

    2009-09-01

    Horseshoe lung, a rare congenital anomaly, is almost always associated with unilateral (usually right-sided) lung hypoplasia, and, in most cases, in conjunction with the scimitar syndrome. We present an 8-month-old boy with horseshoe lung associated with left-lung hypoplasia, left pulmonary artery sling and bilateral agenesis of the upper lobe bronchi, diagnosed by multidetector CT (MDCT) imaging. The study also revealed an anomalous origin of the left vertebral artery as the last branch of the aortic arch, distal to the left subclavian artery, and an anomalous origin of the left common carotid artery from the brachiocephalic trunk. A hemivertebral anomaly of the seventh cervical vertebra was incidentally detected. MDCT with high-quality multiplanar and three-dimensional reconstructions is a noninvasive and rapid technique for detecting the complex combination of vascular, tracheobronchial and parenchymal anomalies, and any potential bone anomalies, in one imaging study.

  12. Horseshoe lung associated with left-lung hypoplasia, left pulmonary artery sling and bilateral agenesis of upper lobe bronchi

    Energy Technology Data Exchange (ETDEWEB)

    Oguz, Berna; Haliloglu, Mithat [Hacettepe University Faculty of Medicine, Department of Radiology, Ankara (Turkey); Alan, Serdar; Ozcelik, Ugur [Hacettepe University Faculty of Medicine, Department of Pediatrics, Ankara (Turkey)

    2009-09-15

    Horseshoe lung, a rare congenital anomaly, is almost always associated with unilateral (usually right-sided) lung hypoplasia, and, in most cases, in conjunction with the scimitar syndrome. We present an 8-month-old boy with horseshoe lung associated with left-lung hypoplasia, left pulmonary artery sling and bilateral agenesis of the upper lobe bronchi, diagnosed by multidetector CT (MDCT) imaging. The study also revealed an anomalous origin of the left vertebral artery as the last branch of the aortic arch, distal to the left subclavian artery, and an anomalous origin of the left common carotid artery from the brachiocephalic trunk. A hemivertebral anomaly of the seventh cervical vertebra was incidentally detected. MDCT with high-quality multiplanar and three-dimensional reconstructions is a noninvasive and rapid technique for detecting the complex combination of vascular, tracheobronchial and parenchymal anomalies, and any potential bone anomalies, in one imaging study. (orig.)

  13. 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.

  14. 烟酰胺对压力致兔腰椎间盘退变的保护作用%The Protective Effect of Nicotinamide on Controllable Axial Loading-induced Rabbit IVD Degeneration Model of Rabbits

    Institute of Scientific and Technical Information of China (English)

    徐蔚蔚; 邵增务; 裴洪; 周建国; 黄吉军; 俞旭东; 熊蠡茗

    2009-01-01

    Objective To investigate the protective effects of nicotinamide against axial loading-induced rabbit intervertebral disc (IVD) degeneration. Methods Twenty-four Japanese white rabbits were randomly divided into 6 groups. Rabbit lumbar disc degeneration model was established by the controllable axial pressure of 98 N. The rabbits were given nicotinamide orally following the grouping. In group l,two rabbits were equipped with the controllable axial pressure device but not subjected to pressure or nicotinamide; In group 2, two rabbits were administered nicotinamide of 50 mg/(kg·d) for one week by gastric ga-vage; In group 3,five rabbits were loaded with controllable axial pressure of 98 N for one week; In group 4,five rabbits were loaded with controllable axial pressure of 98 N for one week,then restored one week by the removal of the pressure; In group 5.five rabbits were loaded with controllable axial pressure of 98 N for one week,and given nicotinamide of 50 mg/ (kg ? D) for one week prior to the removal of the pressure; In group 6,five rabbits were loaded with controllable axial pressure of 98 N for one week and restored one week, and simultaneously given nicotinamide of 50 mg/(kg·d) for two weeks via gastric ga-vage. The rabbit lumbar MRI and Thompson grades were used to score IVD degeneration; HE staining,type Ⅱ collagen immu-nohistochemistry staining and Safranin O-Fast Green staining were done to assess the histological changes in the IVD matrix; P16INK4A immunohistochemistry staining was used to detect the state of cell senescence. Results ① Immunohistochemistry staining of type Ⅱ collagen demonstrated that the pathological changes of IVDs were alleviated, and contents of collagen were increased by 53. 2% in the nicotinamide-treated groups as compared with group 4(P<0. 01) ;②Safranin O-Fast Green staining intensity of both nucleus pulposus (NP) and annular fibrosus in group 2 was increased as compared with group 1. The staining intensity in NP of

  15. Intrathecal cdk5 inhibitor, roscovitine,attenuates morphine antinociceptive tolerance in rats

    Institute of Scientific and Technical Information of China (English)

    Cheng-haung WANG; Tsung-hsing LEE; Yi-jung TSAI; Jong-kang LIU; Yann-jang CHEN; Lin-cheng YANG; Cheng-yuan LU

    2004-01-01

    AIM: To investigate the effect of cyclin-dependent kinase 5 (Cdk5) inhibitor roscovitine on the morphine antinociceptive tolerance development in rats. METHODS: Tail-flick test as pain threshold measurement and intrathecal injection techniques were used. RESULTS: Intrathecal roscovitine infusion alone produced an antinociceptive effect. Tolerance was induced by continuous intrathecal infusion of morphine 5 μg/h for 5 d. Coadministration of intrathecal roscovitine 1 μg/h for 5 d enhanced the morphine antinociceptive effect in tolerant rats.It also caused a shift in the morphine antinociceptive doseCresponse curve to the left when co-administered with morphine during tolerance induction, and caused a 67 % reduction in the increase in the ED50 of morphine (dose producing 50 % of the maximum response). CONCLUSION: Cdk5 modulation is involved in the antinociceptive tolerance of morphine. Intrathecal roscovitine administration could attenuate this tolerance development.

  16. 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.

  17. 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.

  18. Damping factor estimation using spin wave attenuation in permalloy film

    Energy Technology Data Exchange (ETDEWEB)

    Manago, Takashi, E-mail: manago@fukuoka-u.ac.jp [Department of Applied Physics, Fukuoka University, 8-19-1 Nanakuma, Jonan, Fukuoka 814-0180 (Japan); Yamanoi, Kazuto [Department of Physics, Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581 (Japan); Kasai, Shinya; Mitani, Seiji [National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0047 (Japan)

    2015-05-07

    Damping factor of a Permalloy (Py) thin film is estimated by using the magnetostatic spin wave propagation. The attenuation lengths are obtained by the dependence of the transmission intensity on the antenna distance, and decrease with increasing magnetic fields. The relationship between the attenuation length, damping factor, and external magnetic field is derived theoretically, and the damping factor was determined to be 0.0063 by fitting the magnetic field dependence of the attenuation length, using the derived equation. The obtained value is in good agreement with the general value of Py. Thus, this estimation method of the damping factor using spin waves attenuation can be useful tool for ferromagnetic thin films.

  19. [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.

  20. 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.

  1. 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.

  2. Topology optimization of patch-typed left-handed metamaterial configurations for transmission performance within the radio frequency band based on the genetic algorithm

    Science.gov (United States)

    Dong, Yanzhang; Liu, Shutian

    2012-10-01

    For the requirement of broadband transmission with low attenuation within the radio frequency band, a topology optimization model of microstructure configuration design of patch-typed left-handed metamaterials is established, with the objective function defined by the ratio of the mean attenuation to the absolute left-handed bandwidth; then a genetic algorithm based solution method and flow chart of the topology optimization are presented. An improved electromagnetic simulation analysis method is used to obtain accurate equivalent electromagnetic parameters from the S-parameter retrieval process. Three patch-typed microstructure configurations are given according to the results of topology optimization designs for different lattice sizes, and the transmission performance indicators of these creative configurations are computed and analyzed by numerical simulation. The contrast of the design results shows that a U-shaped-like structure of half a unit cell height exists among all these optimum configurations. It is found through a further analysis that the distribution of conduction currents of U-shaped-like structures is the key to broadband transmission with low attenuation. Finally, a new topology optimization design with the perimeter constraint is proposed to solve the problem in the manufacturing process for checkerboard-typed lattices from these configurations.

  3. 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.

  4. 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.

  5. Biomechanical differences between left- and right-handed baseball pitchers.

    Science.gov (United States)

    Solomito, Matthew J; Ferreria, Joel V; Nissen, Carl W

    2016-06-02

    Left-handed baseball pitchers are thought to have a number of theoretical advantages compared to right-handed pitchers; however, there is limited scientific research detailing differences in the pitching mechanics of right- and left-handed pitchers. Therefore, this study sought to understand whether any kinematic and kinetic differences existed between right- and left-handed baseball pitchers. A total of 52 collegiate pitchers were included in this study; 26 left-handed pitchers were compared to 26 age-, height-, weight- and ball velocity-matched right-handed pitchers. Demographic information, passive shoulder range of motion and kinematic and kinetic data were obtained for each pitcher participating in the study. Results indicated that left-handed pitchers did not have a glenohumeral internal rotation deficit as compared to right-handed pitchers. Kinematic analysis indicated that elbow flexion, horizontal glenohumeral abduction and wrist coronal plane motion were significantly different between the two study cohorts. It was also noted that left-handed pitchers had increased elbow varus moments. The findings of this study suggest that pitching coaches should be aware that there are biomechanical differences between left- and right-handed pitchers.

  6. When left is "right". Motor fluency shapes abstract concepts.

    Science.gov (United States)

    Casasanto, Daniel; Chrysikou, Evangelia G

    2011-04-01

    Right- and left-handers implicitly associate positive ideas like "goodness" and "honesty" more strongly with their dominant side of space, the side on which they can act more fluently, and negative ideas more strongly with their nondominant side. Here we show that right-handers' tendency to associate "good" with "right" and "bad" with "left" can be reversed as a result of both long- and short-term changes in motor fluency. Among patients who were right-handed prior to unilateral stroke, those with disabled left hands associated "good" with "right," but those with disabled right hands associated "good" with "left," as natural left-handers do. A similar pattern was found in healthy right-handers whose right or left hand was temporarily handicapped in the laboratory. Even a few minutes of acting more fluently with the left hand can change right-handers' implicit associations between space and emotional valence, causing a reversal of their usual judgments. Motor experience plays a causal role in shaping abstract thought.

  7. Salt and left ventricular hypertrophy: what are the links?

    Science.gov (United States)

    Langenfeld, M R; Schmieder, R E

    1995-11-01

    Left ventricular hypertrophy is a frequent and prognostically unfavourable finding in patients with essential hypertension and has been found to be a predictor for the development of essential hypertension in normotensive subjects. Among various genetic, haemodynamic and humoral determinants, dietary salt intake has been demonstrated to influence left ventricular mass in hypertensive disease. Several cross-sectional studies have shown a close relation between dietary salt intake and parameters of left ventricular hypertrophy. Moreover, reduction of dietary sodium intake was associated with a decrease of left ventricular mass in a prospective study. The underlying mechanism of how salt intake modulates myocardial structure has not been explained yet. Three possible explanations are discussed: (1) sodium influences left ventricular mass via raised preload, (2) the sympathetic nervous system acts as a mediator, and (3) the renin-angiotensin-aldosterone system is the responsible link. Recent animal experiments and clinical studies suggest that the renin-angiotensin-aldosterone system may mediate both the cardiotrophic and the blood pressure raising effects of salt. However, not all individuals have a similar high susceptibility to blood pressure elevation develop left ventricular hypertrophy when exposed to high salt intake. We suggest that the underlying mechanism is a dysregulation of the renin-angiotensin-aldosterone system. Some individuals may have an impaired downregulation of angiotensin II synthesis when challenged with high salt intake. Accordingly, we found that relatively too high levels of angiotensin II in relation to urinary sodium excretion were associated with left ventricular hypertrophy in these individuals on high salt intake.

  8. Left-handedness and achievements in foreign language studies.

    Science.gov (United States)

    Lamm, O; Epstein, R

    1999-12-01

    Studies of brain lateralization lend support to the hypothesis that language-motor functions in left-handers are differently organized from those in right-handers. However, the implications of these differences regarding cognitive functioning are as yet subject to controversy. This concerns all hypotheses raised and empirical data collected over the years. Although it was suggested that left-handers are at higher risk of having language and reading deficits, empirical data from clinical and nonclinical populations are inconclusive at the present time. No effort, however, has been invested in examining possible differences in academic studies of foreign languages according to handedness. Here we report data indicating inferior achievements of left-handed native Hebrew speakers in studies of English as a foreign language. Left-handed pupils significantly more than right-handers were placed in lower level English classes and had more difficulties in applying orthographic-phonological mapping rules in reading English words and pseudowords. However, left-handers' difficulties in this task were not correlated with their performance in a word recognition task. It is thus suggested that the "common symptom" of poor word reading in left-handers indicates different processing failures in different left-handers, some of which impede the buildup of an internal representational system of mapping orthography to phonology and some of which concern mainly the precision of word production.

  9. 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

  10. 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.

  11. Crab scars reveal survival advantage of left-handed snails.

    Science.gov (United States)

    Dietl, Gregory P; Hendricks, Jonathan R

    2006-09-22

    Biological asymmetries are important elements of the structure and function of many living organisms. Using the Plio-Pleistocene fossil record of crab predation on morphologically similar pairs of right- and left-handed snail species, we show here for the first time, contrary to traditional wisdom, that rare left-handed coiling promotes survival from attacks by right-handed crabs. This frequency-dependent result influences the balance of selection processes that maintain left-handedness at the species level and parallels some social interactions in human cultures, such as sports that involve dual contests between opponents of opposite handedness.

  12. Left-handedness in blind and sighted children.

    Science.gov (United States)

    Caliskan, Erkan; Dane, Senol

    2009-03-01

    Rates of left-handedness were compared in 1387 blind and 831 sighted children. The rate in male blind children was higher than in female blind children. The incidence of left-handedness was significantly higher in blind than in sighted children in both boys and girls. The percentages of left-handedness were 18.23% and 17.02% in male and female blind children, and 11.02% and 7.52% in male and female sighted children, respectively. It can be stated that sighting is important in the development of normal typical cerebral lateralisation or hand preference.

  13. 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.

  14. Left-sided gall bladder: Report of two cases

    Directory of Open Access Journals (Sweden)

    Chrungoo R

    2007-01-01

    Full Text Available Left-sided gall bladder without situs inversus viscerum is a rare albeit recognized clinical entity. We report our experience of two cases of left-sided gall bladder in two women aged 36 and 48 who underwent laparoscopic cholecystectomy for chronic calculous cholecystitis. Left-sided gall bladder may provide an unusual surprise to the surgeons during laparoscopy as routine pre-operative studies may not always detect the anomaly. Awareness of the unpredictable confluence of the cystic duct into the common bile duct (CBD and selective use of intraoperative cholangiography aid in the safe laparoscopic management of this unusual entity.

  15. Total occlusion of left main coronary artery without angina pectoris.

    Science.gov (United States)

    DePace, N L; Kimbiris, D; Iskandrian, A S; Bemis, C E; Segal, B L

    1983-05-01

    A patient had total occlusion of the left main coronary artery that was proved by coronary arteriography. The patient was initially seen with clinical signs of congestive heart failure but without symptoms of angina pectoris or ECG evidence of myocardial infarction. The patient's extensive right-to-left coronary artery collaterals may have contributed to the absence of chest pain. Because of the severe left ventricular dysfunction and the absence of chest pain, the patient was treated with medical therapy. Six months after the cardiac catheterization, he was alive and well under New York Heart Association functional classification II.

  16. Dark Matter in Lepto-Baryonic Left-Right Theories

    CERN Document Server

    Patra, Sudhanwa

    2015-01-01

    A Lepto-Baryonic Left-Right symmetric theory is considered where leptons and baryons are local gauge symmetries. These theories are generally anomalous and the possible gauge anomaly free solutions for these theories are presented here. This paper also shows different ways in which Lepto-Baryonic Left-Right theories are broken down to Standard Model gauge group which further breaks down to low energy by SM Higgs boson. It is found that the neutral component of fermion triplets can be a viable dark matter candidate originally introduced for gauge anomaly cancellation. The other dark matter possibilities within this Lepto-Baryonic Left-Right symmetric theories are also presented.

  17. Right Handed Quark Mixing in Left-Right Symmetric Theory

    CERN Document Server

    Senjanović, Goran

    2014-01-01

    We give exact formulas for the right-handed analog of the CKM matrix in the minimal Left-Right symmetric theory, for the case when the Left-Right symmetry is generalised Parity as in the original version of the theory. We derive its explicit form and give a physical reason for the known and surprising fact that the right-handed mixing angles are close to the CKM ones, in spite of the Left-Right symmetry being badly broken in nature.

  18. Right Handed Quark Mixing in Left-Right Symmetric Theory

    OpenAIRE

    Senjanović, Goran; Tello, Vladimir

    2014-01-01

    We give exact formulas for the right-handed analog of the CKM matrix in the minimal Left-Right symmetric theory, for the case when the Left-Right symmetry is generalized Parity as in the original version of the theory. We derive its explicit form and give a physical reason for the known and surprising fact that the right-handed mixing angles are close in value to the CKM ones, in spite of the Left-Right symmetry being badly broken in nature. We exemplify our results on the production of the r...

  19. 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.

  20. 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)

  1. 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.

  2. 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

  3. 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. .

  4. Hollow antiresonant fibers with reduced attenuation.

    Science.gov (United States)

    Belardi, Walter; Knight, Jonathan C

    2014-04-01

    An improved design for hollow antiresonant fibers (HAFs) is presented. It consists of adding extra antiresonant glass elements within the air cladding region of an antiresonant hollow-core fiber. We use numerical simulations to compare fiber structures with and without the additional cladding elements in the near- and mid-IR regimes. We show that realizable fiber structures can provide greatly improved performance in terms of leakage and bending losses compared to previously reported antiresonant fibers. At mid-IR wavelengths, the adoption of this novel fiber design will lead to HAFs with reduced bending losses. In the near-IR, this design could lead to the fabrication of HAFs with very low attenuation.

  5. Evidence of oxidative attenuation of auxin signalling.

    Science.gov (United States)

    Peer, Wendy Ann; Cheng, Yan; Murphy, Angus S

    2013-06-01

    Indole-3-acetic acid (IAA) is the principle auxin in Arabidopsis and is synthesized primarily in meristems and nodes. Auxin is transported to distal parts of the plant in response to developmental programming or environmental stimuli to activate cell-specific responses. As with any signalling event, the signal must be attenuated to allow the system to reset. Local auxin accumulations are thus reduced by conjugation or catabolism when downstream responses have reached their optima. In most cell types, localized auxin accumulation increases both reactive oxygen species (ROS) and an irreversible catabolic product 2-oxindole-3-acid acid (oxIAA). oxIAA is inactive and does not induce expression of the auxin-responsive reporters DR5 or 2XD0. Here it is shown that oxIAA is not transported from cell to cell, although it appears to be a substrate for the ATP-binding cassette subfamily G (ABCG) transporters that are positioned primarily on the outer lateral surface of the root epidermis. However, oxIAA and oxIAA-Glc levels are higher in ABCB mutants that accumulate auxin due to defective cellular export. Auxin-induced ROS production appears to be at least partially mediated by the NAD(P)H oxidase RbohD. oxIAA levels are higher in mutants that lack ROS-scavenging flavonoids (tt4) and are lower in mutants that accumulate excess flavonols (tt3). These data suggest a model where IAA signalling is attenuated by IAA catabolism to oxIAA. Flavonoids appear to buffer ROS accumulations that occur with localized increases in IAA. This buffering of IAA oxidation would explain some growth responses observed in flavonoid-deficient mutants that cannot be explained by their established role in partially inhibiting auxin transport.

  6. Over-expression of calpastatin inhibits calpain activation and attenuates post-infarction myocardial remodeling.

    Directory of Open Access Journals (Sweden)

    Tingqiao Ye

    Full Text Available Calpain is activated following myocardial infarction and ablation of calpastatin (CAST, an endogenous inhibitor of calpains, promotes left ventricular remodeling after myocardial infarction (MI. The present study aimed to investigate the effect of transgenic over-expression of CAST on the post-infarction myocardial remodeling process.We established transgenic mice (TG ubiquitously over-expressing human CAST protein and produced MI in TG mice and C57BL/6J wild-type (WT littermates.The CAST protein expression was profoundly upregulated in the myocardial tissue of TG mice compared with WT littermates (P < 0.01. Overexpression of CAST significantly reduced the infarct size (P < 0.01 and blunted MI-induced interventricular hypertrophy, global myocardial fibrosis and collagen I and collagen III deposition, hypotension and hemodynamic disturbances at 21 days after MI. Moreover, the MI-induced up-regulation and activation of calpains were obviously attenuated in CAST TG mice. MI-induced down-regulation of CAST was partially reversed in TG mice. Additionally, the MI-caused imbalance of matrix metalloproteinases and their inhibitors was improved in TG mice.Transgenic over-expression of CAST inhibits calpain activation and attenuates post-infarction myocardial remodeling.

  7. 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.

  8. 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.

  9. [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.

  10. 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.

  11. 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.

  12. 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.

  13. Left main coronary artery compression in pulmonary arterial hypertension

    DEFF Research Database (Denmark)

    Al-Badri, Kadhem Helo Abbas; Jensen, Jesper Møller; Christiansen, Evald H;

    2015-01-01

    . The diagnosis was verified by electrocardiogram after exercise, coronary angiography including intravascular ultrasound, and cardiac multidetector computed tomography (MDCT). The origin of the LMCA was high in the left coronary sinus, facilitating extrinsic compression. The patient was successfully treated...

  14. Autosomal dominant inheritance of left ventricular outflow tract obstruction

    NARCIS (Netherlands)

    Wessels, Marjolein; Berger, Rudolphus; Frohn-Mulder, Ingrid M E; Roos-Hesselink, Jolien W; Hoogeboom, Jeanette J M; Mancini, Grazia S; Bartelings, Margot M; Krijger, Ronald de; Wladimiroff, Jury W; Niermeijer, Martinus F; Grossfeld, Paul; Willems, Patrick J

    2005-01-01

    Most nonsyndromic congenital heart malformations (CHMs) in humans are multifactorial in origin, although an increasing number of monogenic cases have been reported recently. We describe here four new families with presumed autosomal dominant inheritance of left ventricular outflow tract obstruction

  15. 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.

  16. 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.

  17. Anatomical variation of the origin of the left vertebral artery

    Directory of Open Access Journals (Sweden)

    Patasi B

    2009-08-01

    Full Text Available This paper presents and describes the anatomical variation of the left vertebral artery originating from the arch of aorta as a case report. This variation was found in one of the cadavers at the Division of Clinical and Functional Anatomy, Faculty of Medicine, University of Ottawa. During routine dissection of a male cadaver, in the superior mediastinum and the neck we observed an atypical origin of the left vertebral artery. Atypical origin was compared to the typical origin of the left vertebral artery in the anatomical literature. We compared our findings with different possible variations of the origin of the left vertebral artery reported in the literature. The clinical importance of the variation is discussed.

  18. Stochastic left-right neuronal asymmetry in Caenorhabditis elegans.

    Science.gov (United States)

    Alqadah, Amel; Hsieh, Yi-Wen; Xiong, Rui; Chuang, Chiou-Fen

    2016-12-19

    Left-right asymmetry in the nervous system is observed across species. Defects in left-right cerebral asymmetry are linked to several neurological diseases, but the molecular mechanisms underlying brain asymmetry in vertebrates are still not very well understood. The Caenorhabditis elegans left and right amphid wing 'C' (AWC) olfactory neurons communicate through intercellular calcium signalling in a transient embryonic gap junction neural network to specify two asymmetric subtypes, AWC(OFF) (default) and AWC(ON) (induced), in a stochastic manner. Here, we highlight the molecular mechanisms that establish and maintain stochastic AWC asymmetry. As the components of the AWC asymmetry pathway are highly conserved, insights from the model organism C. elegans may provide a window onto how brain asymmetry develops in humans.This article is part of the themed issue 'Provocative questions in left-right asymmetry'.

  19. 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.

  20. Right-left and the scrotum in Greek sculpture.

    Science.gov (United States)

    McManus, I C

    2004-04-01

    The scrotum in humans is asymmetric, the right testicle being visibly higher than the left in most men. Paradoxically, it is also the case that the right testicle is somewhat larger, rather than smaller, as might be expected. Greek classical and pre-classical art, which took great care in its attention to anatomical detail, correctly portrayed the right testicle as the higher, but then incorrectly portrayed the left testicle as visibly larger. The implication is that the Greeks used a simple mechanical theory, the left testicle being thought to be lower because it was larger and hence more subject to the pull of gravity. The present study examines data on scrotal asymmetry in more detail, and puts them in the context of Greek theories of functional differences between the right side and the left side.

  1. 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.

  2. 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...

  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...... or principle for a neoliberal stance. The author relates the risks in neoliberal thought for losing what is specific in definitive statements and the loss of neoliberal thought coherence within a reality....

  4. 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.

  5. Left wind forward in football (soccer). Khinanthropometry and footprint analysis

    OpenAIRE

    Herrero de Lucas, A.; Cabañas Armesilla, M.D.; Maestre López, I.

    2004-01-01

    Kinanthropometry is the study of size, shape, proportionality, body composition, biological maturation and body function with the objective of understanding the process of growth, exercise, sport performance and nutrition. It has been accepted measurements in the right side of the subject as equivalent of the overall sportsman. Right and left side variations therefore have not been sufficiently studied, particularly in left handed football players. Materials and Methods: Analysis ...

  6. Left-right asymmetry: lessons from Cancún

    OpenAIRE

    Burdine, Rebecca D.; Caspary, Tamara

    2013-01-01

    The satellite symposium on ‘Making and breaking the left-right axis: implications of laterality in development and disease’ was held in June 2013 in conjunction with the 17th International Society for Developmental Biology meeting in Cancún, Mexico. As we summarize here, leaders in the field gathered at the symposium to discuss recent advances in understanding how left-right asymmetry is generated and utilized across the animal kingdom.

  7. Preterm Delivery in the Setting of Left Calyceal Rupture

    OpenAIRE

    2015-01-01

    Spontaneous rupture of the renal collecting system is a rare but serious complication of pregnancy. We report a case of nontraumatic left renal calyceal rupture in a pregnancy which ultimately progressed to preterm delivery. A 29-year-old primigravida with a remote history of urolithiasis presented with left flank pain, suprapubic pain, and signs of preterm labor at 33 weeks of gestation. The patient was believed to have urolithiasis, although initial renal ultrasound failed to demonstrate de...

  8. 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.

  9. 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.

  10. Scattering Forces within a Left-Handed Photonic Crystal.

    Science.gov (United States)

    Ang, Angeleene S; Sukhov, Sergey V; Dogariu, Aristide; Shalin, Alexander S

    2017-01-23

    Electromagnetic waves are known to exert optical forces on particles through radiation pressure. It was hypothesized previously that electromagnetic waves inside left-handed metamaterials produce negative radiation pressure. Here we numerically examine optical forces inside left-handed photonic crystals demonstrating negative refraction and reversed phase propagation. We demonstrate that even though the direction of force might not follow the flow of energy, the positive radiation pressure is maintained inside photonic crystals.

  11. Regional renal venous hypertension and left-sided varicocele

    OpenAIRE

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

    2014-01-01

    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...

  12. 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”.

  13. 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.

  14. 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...

  15. 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.

  16. 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

  17. Light attenuation characteristics of glacially-fed lakes

    Science.gov (United States)

    Rose, Kevin C.; Hamilton, David P.; Williamson, Craig E.; McBride, Chris G.; Fischer, Janet M.; Olson, Mark H.; Saros, Jasmine E.; Allan, Mathew G.; Cabrol, Nathalie

    2014-07-01

    Transparency is a fundamental characteristic of aquatic ecosystems and is highly responsive to changes in climate and land use. The transparency of glacially-fed lakes may be a particularly sensitive sentinel characteristic of these changes. However, little is known about the relative contributions of glacial flour versus other factors affecting light attenuation in these lakes. We sampled 18 glacially-fed lakes in Chile, New Zealand, and the U.S. and Canadian Rocky Mountains to characterize how dissolved absorption, algal biomass (approximated by chlorophyll a), water, and glacial flour contributed to attenuation of ultraviolet radiation (UVR) and photosynthetically active radiation (PAR, 400-700 nm). Variation in attenuation across lakes was related to turbidity, which we used as a proxy for the concentration of glacial flour. Turbidity-specific diffuse attenuation coefficients increased with decreasing wavelength and distance from glaciers. Regional differences in turbidity-specific diffuse attenuation coefficients were observed in short UVR wavelengths (305 and 320 nm) but not at longer UVR wavelengths (380 nm) or PAR. Dissolved absorption coefficients, which are closely correlated with diffuse attenuation coefficients in most non-glacially-fed lakes, represented only about one quarter of diffuse attenuation coefficients in study lakes here, whereas glacial flour contributed about two thirds across UVR and PAR. Understanding the optical characteristics of substances that regulate light attenuation in glacially-fed lakes will help elucidate the signals that these systems provide of broader environmental changes and forecast the effects of climate change on these aquatic ecosystems.

  18. Ultrasonic velocity and attenuation anisotropy of shales, Whitby, United Kingdom

    NARCIS (Netherlands)

    Zhubayev, A.; Houben, M.E.; Smeulders, D.M.J.; Barnhoorn, A.

    2015-01-01

    We have conducted ultrasonic experiments, between 0.3 and 1 MHz, to measure velocity and attenuation (Q−1) anisotropy of P- and S-waves in dry Whitby Mudstone samples as a function of stress. We found the degree of anisotropy to be as large as 70% for velocity and attenuation. The sensitivity of P-w

  19. Ultrasonic velocity and attenuation anisotropy of shales, Whitby, United Kingdom

    NARCIS (Netherlands)

    Zhubayev, Alimzhan; Houben, M.E.; Smeulders, David; Barnhoorn, A.

    2016-01-01

    We have conducted ultrasonic experiments, between 0.3 and 1 MHz, to measure velocity and attenuation (Q−1) anisotropy of P- and S-waves in dry Whitby Mudstone samples as a function of stress. We found the degree of anisotropy to be as large as 70% for velocity and attenuation. The sensitivity of P-w

  20. Attenuated radon transform: theory and application in medicine and biology

    Energy Technology Data Exchange (ETDEWEB)

    Gullberg, G.T.

    1979-06-01

    A detailed analysis is given of the properties of the attenuated Radon transform and of how increases in photon attenuation influence the numerical accuracy and computation efficiency of iterative and convolution algorithms used to determine its inversion. The practical applications for this work involve quantitative assessment of the distribution of injected radiopharmaceuticals and radionuclides in man and animals for basic physiological and biochemical studies as well as clinical studies in nuclear medicine. A mathematical structure is developed using function theory and the theory of linear operators on Hilbert spaces which lends itself to better understanding the spectral properties of the attenuated Radon transform. The continuous attenuated Radon transform reduces to a matrix operator for discrete angular and lateral sampling, and the reconstruction problem reduces to a system of linear equations. For the situation of variable attenuation coefficient frequently found in nuclear medicine applications of imaging the heart and chest, the procedure developed in this thesis involves iterative techniques of performing the generalized inverse. For constant attenuation coefficient less than 0.15 cm/sup -1/, convolution methods can reliably reconstruct a 30 cm object with 0.5 cm resolution. However, for high attenuation coefficients or for the situation where there is variable attenuation such as reconstruction of distribution of isotopes in the heart, iterative techniques developed in this thesis give the best results. (ERB)

  1. 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.

  2. Ultrasound attenuation dependence on air compression or expansion processes

    NARCIS (Netherlands)

    Jakevicius, L.; Demcenko, A.; Mardosaite, R.

    2010-01-01

    In this work variation of ultrasonic attenuation coefficient is analyzed in terms of air compression or expansion processes. In closed spaces changing air volume, the ultrasound attenuation coefficient depends on thermodynamic processes which occur during the air volume change. Two limiting cases ar

  3. Excess attenuation of an acoustic beam by turbulence.

    Science.gov (United States)

    Pan, Naixian

    2003-12-01

    A theory based on the concept of a spatial sinusoidal diffraction grating is presented for the estimation of the excess attenuation in an acoustic beam. The equation of the excess attenuation coefficient shows that the excess attenuation of acoustic beam not only depends on the turbulence but also depends on the application parameters such as the beam width, the beam orientation and whether for forward propagation or back scatter propagation. Analysis shows that the excess attenuation appears to have a frequency dependence of cube-root. The expression for the excess attenuation coefficient has been used in the estimations of the temperature structure coefficient, C(T)2, in sodar sounding. The correction of C(T)2 values for excess attenuation reduces their errors greatly. Published profiles of temperature structure coefficient and the velocity structure coefficient in convective conditions are used to test our theory, which is compared with the theory by Brown and Clifford. The excess attenuation due to scattering from turbulence and atmospheric absorption are both taken into account in sodar data processing for deducing the contribution of the lower atmosphere to seeing, which is the sharpness of a telescope image determined by the degree of turbulence in the Earth's atmosphere. The comparison between the contributions of the lowest 300-m layer to seeing with that of the whole atmosphere supports the reasonableness of our estimation of excess attenuation.

  4. 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.

  5. 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.

  6. Left hand dominance affects supra-second time processing

    Directory of Open Access Journals (Sweden)

    Carmelo Mario Vicario

    2011-10-01

    Full Text Available Previous works exploring the brain functions of left-handed and right-handed people 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 temporal intervals, we designed a study investigating timing abilities in left-handed subjects. To this purpose left-handed and right-handed subjects were asked to perform a time reproduction of sub-second vs. supra-second time intervals with their left and right hand.Our results show that left-handed participants sub-estimated the processing of the supra-second intervals, independently of the hand used to perform the task, while no differences were reported for the sub-second intervals. These results are discussed according to recent advances on suprasecond motor timing research as well as emerging evidences which suggest a linear representation of time with a left-to-right displacing.

  7. 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.

  8. Preterm Delivery in the Setting of Left Calyceal Rupture

    Directory of Open Access Journals (Sweden)

    Brent Hanson

    2015-01-01

    Full Text Available Spontaneous rupture of the renal collecting system is a rare but serious complication of pregnancy. We report a case of nontraumatic left renal calyceal rupture in a pregnancy which ultimately progressed to preterm delivery. A 29-year-old primigravida with a remote history of urolithiasis presented with left flank pain, suprapubic pain, and signs of preterm labor at 33 weeks of gestation. The patient was believed to have urolithiasis, although initial renal ultrasound failed to demonstrate definitive calculi. After a temporary improvement in flank pain with medication, the patient experienced acute worsening of her left flank pain. Urology was consulted and further imaging was obtained. Magnetic resonance imaging (MRI was consistent with bilateral hydronephrosis and rupture of the left renal calyx. Given the patient’s worsening pain in the setting of left calyceal rupture, the urology team planned for placement of a left ureteral stent. However, before the patient could receive her stent, she progressed to active labor and delivered a viable female infant vaginally. Following delivery, the patient’s flank pain resolved rapidly and spontaneously, so no surgical intervention was performed. A summary of the literature and the details of this specific clinical situation are provided.

  9. Preterm Delivery in the Setting of Left Calyceal Rupture

    Science.gov (United States)

    Hanson, Brent; Tabbarah, Rami

    2015-01-01

    Spontaneous rupture of the renal collecting system is a rare but serious complication of pregnancy. We report a case of nontraumatic left renal calyceal rupture in a pregnancy which ultimately progressed to preterm delivery. A 29-year-old primigravida with a remote history of urolithiasis presented with left flank pain, suprapubic pain, and signs of preterm labor at 33 weeks of gestation. The patient was believed to have urolithiasis, although initial renal ultrasound failed to demonstrate definitive calculi. After a temporary improvement in flank pain with medication, the patient experienced acute worsening of her left flank pain. Urology was consulted and further imaging was obtained. Magnetic resonance imaging (MRI) was consistent with bilateral hydronephrosis and rupture of the left renal calyx. Given the patient's worsening pain in the setting of left calyceal rupture, the urology team planned for placement of a left ureteral stent. However, before the patient could receive her stent, she progressed to active labor and delivered a viable female infant vaginally. Following delivery, the patient's flank pain resolved rapidly and spontaneously, so no surgical intervention was performed. A summary of the literature and the details of this specific clinical situation are provided. PMID:26483981

  10. Concentric left ventricular morphology in aerobically trained kayak canoeists.

    Science.gov (United States)

    Gates, Phillip E; Campbell, Ian G; George, Keith P

    2004-09-01

    The aim of the present study was to test the hypothesis that upper body aerobically trained athletes (kayak canoeists) would have greater left ventricular wall thickness, but similar left ventricular diastolic chamber dimensions, compared with recreationally active and sedentary men. Ultrasound echocardiography was used to determine cardiac structure and function in highly trained kayak canoeists (n = 10), moderately active (n = 10) and sedentary men (n = 10). The septal and posterior left ventricular walls were approximately 0.2 cm thicker in kayak canoeists (P kayak canoeists had a concentric pattern of left ventricular adaptation to aerobic upper body training. Scaling the data to body composition indices had no effect on the outcome of the statistical analysis. There were no differences in resting Doppler left ventricular diastolic or systolic function among the groups. Ejection fraction was lower in the kayak canoeists, but the magnitude of the difference was within the normal variability for this measurement. Thus aerobically upper body trained athletes demonstrated a concentric pattern of cardiac enlargement, but resting left ventricle function was not different between athletes, moderately active and sedentary individuals.

  11. Right-left discrimination: effects of handedness and educational background.

    Science.gov (United States)

    Ofte, Sonja H

    2002-07-01

    The present study investigated right left discrimination, with a paper-and-pen test with cartoon figures. The test consisted of line drawings of a person with no, one, or both arms crossing the vertical axis of the body in the figure. The subjects' task was to mark with a pencil, as fast as possible, which was the right or left hand in the figure. The line drawings were viewed from the back, from the front, or randomly alternating between the back and front views. Two studies were conducted. The first consisted of 393 adults: 153 males and 240 females; 338 right-handers and 55 left-handers. The results showed that the males performed better than the females. The left-handers and the right-handers performed equally well. However, the left-handed males performed better than the right-handed males. There was no difference in performance between the right-handed and the left-handed females. The second study consisted of 175 right-handed college students: 63 psychology students. 54 medical students, and 58 law students. The main finding was that the medical students performed better than the psychology students for all figure orientation subtests and for all arm positions. In comparison with the law students, the medical students performed at the same level on the back view subtest, but they performed better on the front view subtest and on two out of three arm positions on the alternating view subtest.

  12. 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.

  13. 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.

  14. Effect of lead attenuators on dose in homogeneous phantoms

    Energy Technology Data Exchange (ETDEWEB)

    El-Khatib, E.E.; Podgorsak, E.B.; Pla, C.

    1986-11-01

    In radiotherapy, the radiation beam is sometimes shaped so as to deliver different doses to different organs or give a homogeneous dose to structures of different densities. This objective is achieved by the use of attenuating materials introduced into the beam. These attenuators alter the primary as well as the scattered radiation components of the beam. There is at present no accurate method of dose calculation for these situations. Most calculations are performed considering only the effect of the attenuators on the primary radiation beam and can produce large errors in dosimetry. In the present study, the broad beam attenuation is investigated in homogeneous phantoms for various radiation field sizes, photon beam energies, and depths in phantom. A calculational method taking account of primary as well as first scatter radiation is developed. This method predicts reasonably well the transmission through lead attenuators for the various experimental conditions investigated.

  15. EFFECTS OF RAIN ATTENUATION ON SATELLITE COMMUNICATION LINK

    Directory of Open Access Journals (Sweden)

    G. N. Ezeh

    2014-06-01

    Full Text Available Rain attenuation is a major challenge to microwave satellite communication especially at frequencies above 10 GHz, causing unavailability of signals most of the time. Rain attenuation predictions have become one of the vital considerations while setting up a satellite communication link. In this study, rain attenuation models, cumulative distribution curves and other analytical tools for successful prediction of rain attenuation are presented. A three year Rain rate data was obtained from the Nigeria Meteorological Agency (NIMET database in addition to experimental data. Of the three prediction models used in the study, Ajayi model gave the range of values closest to the experimental data. A correctional factor was determined as 1.0988 and used to modify the Ajayi model. This modification to Ajayi’s model enabled its rain attenuation values conform more closely to the experimental result.

  16. 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.

  17. 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.

  18. 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.

  19. 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 ...

  20. 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...

  1. Seismic attenuation of the inner core: Viscoelastic or stratigraphic?

    Science.gov (United States)

    Cormier, V.F.; Xu, L.; Choy, G.L.

    1998-01-01

    Broadband velocity waveforms of PKIKP in the distance range 150??to 180??are inverted for inner core attenuation. A mean Q?? of 244 is determined at 1 Hz from 8 polar and 9 equatorial paths. The scatter in measured Q-1 exceeds individual error estimates, suggesting significant variation in attenuation with path. These results are interpreted by (1) viscoelasticity, in which the relaxation spectrum has a low-frequency corner near or slightly above the frequency band of short-period body waves, and by (2) stratigraphic (scattering) attenuation, in which attenuation and pulse broadening are caused by the interference of scattered multiples in a velocity structure having rapid fluctuations along a PKIKP path. In the scattering interpretation, PKIKP attenuation is only weakly affected by the intrinsic shear attenuation measured in the free-oscillation band. Instead, its frequency dependence, path variations, and fluctuations are all explained by scattering attenuation in a heterogeneous fabric resulting from solidification texturing of intrinsically anisotropic iron. The requisite fabric may consist of either single or ordered groups of crystals with P velocity differences of at least 5% and as much as 12% between two crystallographic axes at scale lengths of 0.5 to 2 km in the direction parallel to the axis of rotation and longer in the cylindrically radial direction, perpendicular to the axis of rotation.Broadband velocity waveforms of PKIKP in the distance range 150?? to 180?? are inverted for inner core attenuation. A mean Q?? of 244 is determined at 1 Hz from 8 polar and 9 equatorial paths. The scatter in the measured Q-1 exceeds individual error estimates, indicating significant variation in attenuation with path. The results are interpreted by viscoelasticity and stratigraphic (scattering) attenuation.

  2. Persistent left cranial vena cava draining into the left atrium associated with pulmonary stenosis in a French bulldog.

    Science.gov (United States)

    Zani, Alessandro; Becchetti, Elisa; Leonardi, Paola; Sinatra, Alessandro

    2014-06-01

    A 5-month-old female French bulldog was evaluated for the presence of a heart murmur. Through clinical and echocardiographic evaluations, a severe Type A pulmonary stenosis was diagnosed. Angiography during right ventricular catheterization for valvuloplasty revealed drainage from a persistent left cranial vena cava (PLCVC) into the left atrium; this was confirmed later by contrast echocardiography. This report is the first to describe this anatomical variant of a PLCVC in a dog.

  3. '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.

  4. Left ventricular ejection fraction and left ventricular end-diastolic volume in patients with diastolic dysfunction.

    Science.gov (United States)

    Jovin, Ion S; Ebisu, Keita; Liu, Yi-Hwa; Finta, Laurie A; Oprea, Adriana D; Brandt, Cynthia A; Dziura, James; Wackers, Frans J

    2013-01-01

    Diastolic dysfunction can be diagnosed on equilibrium radionuclide angiocardiography (ERNA) by a low peak filling rate (PFR) in the setting of a normal left ventricular ejection fraction (LVEF). The authors evaluated the relationship between diastolic dysfunction, LVEF, and end-diastolic volume (EDV). A total of 408 predominantly asymptomatic patients with an LVEF ≥50% by ERNA were studied. LVEF of patients with a low PFR was compared with the LVEF of patients with a normal PFR. Correlation analyses to evaluate the association between PFR and EDV were also performed. The LVEF of patients with a low PFR was lower than the LVEF of patients with normal PFR (59±7 vs 63%±7%; PPFR (r=-0.04; P=.32). The results did not change when the EDV indices were used. In patients who had repeat scans, there was no correlation between the change in EDV and the change in PFR (r=0.16; P=.2). In asymptomatic patients undergoing ERNA who have normal systolic function, a low PFR can be associated with a lower LVEF, but it is not associated with changes in EDV. This suggests that diastolic dysfunction is associated with mild systolic dysfunction.

  5. 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.

  6. A survey of left-handed helices in protein structures.

    Science.gov (United States)

    Novotny, Marian; Kleywegt, Gerard J

    2005-03-25

    All naturally occurring amino acids with the exception of glycine contain one or more chiral carbon atoms and can therefore occur in two different configurations, L (levo, left-handed) and D (dextro, right-handed). Proteins are almost exclusively built from L-amino acids. The stereochemical bias of nature is further reflected at the secondary structure level where right-handed helices are strongly preferred over left-handed helices. The handedness of helices has not received much attention in the past and is often overlooked during the analysis, description and deposition of experimentally solved protein structures. Therefore, an extensive survey of left-handed helices in the Protein Data Bank (PDB) was undertaken to analyse their frequency of occurrence, length, amino acid composition, conservation and possible structural or functional role. All left-handed helices (of four or more residues) in a non-redundant subset of the PDB, were identified using hydrogen-bonding analysis, comparison of related structures, and experimental electron density assessment to filter out likely spurious and artefactual hits. This analysis yielded 31 verified left-handed helices in a set of 7284 proteins. The phi angles of the residues in the left-handed helices lie between 30 degrees and 130 degrees and the psi angles lie between -50 degrees and 100 degrees . Most of the helices are short (four residues) and for 87% of them, it was possible to determine that they are important for the stability of the protein, for ligand binding, or as part of the active site. This suggests that, even though left-handed helices are rare, when they do occur, they are structurally or functionally significant. Four secondary structure assignment programs were tested for their ability to identify the handedness of the helices. Of these programs, only DSSP correctly assigns the handedness.

  7. 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.

  8. 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.

  9. Improving left spatial neglect through music scale playing.

    Science.gov (United States)

    Bernardi, Nicolò Francesco; Cioffi, Maria Cristina; Ronchi, Roberta; Maravita, Angelo; Bricolo, Emanuela; Zigiotto, Luca; Perucca, Laura; Vallar, Giuseppe

    2017-03-01

    The study assessed whether the auditory reference provided by a music scale could improve spatial exploration of a standard musical instrument keyboard in right-brain-damaged patients with left spatial neglect. As performing music scales involves the production of predictable successive pitches, the expectation of the subsequent note may facilitate patients to explore a larger extension of space in the left affected side, during the production of music scales from right to left. Eleven right-brain-damaged stroke patients with left spatial neglect, 12 patients without neglect, and 12 age-matched healthy participants played descending scales on a music keyboard. In a counterbalanced design, the participants' exploratory performance was assessed while producing scales in three feedback conditions: With congruent sound, no-sound, or random sound feedback provided by the keyboard. The number of keys played and the timing of key press were recorded. Spatial exploration by patients with left neglect was superior with congruent sound feedback, compared to both Silence and Random sound conditions. Both the congruent and incongruent sound conditions were associated with a greater deceleration in all groups. The frame provided by the music scale improves exploration of the left side of space, contralateral to the right hemisphere, damaged in patients with left neglect. Performing a scale with congruent sounds may trigger at some extent preserved auditory and spatial multisensory representations of successive sounds, thus influencing the time course of space scanning, and ultimately resulting in a more extensive spatial exploration. These findings offer new perspectives also for the rehabilitation of the disorder.

  10. 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.

  11. Agmatine attenuates silica-induced pulmonary fibrosis.

    Science.gov (United States)

    El-Agamy, D S; Sharawy, M H; Ammar, E M

    2014-06-01

    There is a large body of evidence that nitric oxide (NO) formation is implicated in mediating silica-induced pulmonary fibrosis. As a reactive free radical, NO may not only contribute to lung parenchymal tissue injury but also has the ability to combine with superoxide and form a highly reactive toxic species peroxynitrite that can induce extensive cellular toxicity in the lung tissues. This study aimed to explore the effect of agmatine, a known NO synthase inhibitor, on silica-induced pulmonary fibrosis in rats. Male Sprague Dawley rats were treated with agmatine for 60 days following a single intranasal instillation of silica suspension (50 mg in 0.1 ml saline/rat). The results revealed that agmatine attenuated silica-induced lung inflammation as it decreased the lung wet/dry weight ratio, protein concentration, and the accumulation of the inflammatory cells in the bronchoalveolar lavage fluid. Agmatine showed antifibrotic activity as it decreased total hydroxyproline content of the lung and reduced silica-mediated lung inflammation and fibrosis in lung histopathological specimen. In addition, agmatine significantly increased superoxide dismutase (p pulmonary nitrite/nitrate as well as tumor necrosis factor α. Collectively, these results demonstrate the protective effects of agmatine against the silica-induced lung fibrosis that may be attributed to its ability to counteract the NO production, lipid peroxidation, and regulate cytokine effects.

  12. Photoacoustic imaging taking into account thermodynamic attenuation

    Science.gov (United States)

    Acosta, Sebastián; Montalto, Carlos

    2016-11-01

    In this paper we consider a mathematical model for photoacoustic imaging which takes into account attenuation due to thermodynamic dissipation. The propagation of acoustic (compressional) waves is governed by a scalar wave equation coupled to the heat equation for the excess temperature. We seek to recover the initial acoustic profile from knowledge of acoustic measurements at the boundary. We recognize that this inverse problem is a special case of boundary observability for a thermoelastic system. This leads to the use of control/observability tools to prove the unique and stable recovery of the initial acoustic profile in the weak thermoelastic coupling regime. This approach is constructive, yielding a solvable equation for the unknown acoustic profile. Moreover, the solution to this reconstruction equation can be approximated numerically using the conjugate gradient method. If certain geometrical conditions for the wave speed are satisfied, this approach is well-suited for variable media and for measurements on a subset of the boundary. We also present a numerical implementation of the proposed reconstruction algorithm.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.)

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. [Heart failure with preserved left ventricular ejection fraction].

    Science.gov (United States)

    Maeder, Micha T; Rickli, Hans

    2013-10-16

    Heart failure with preserved left ventricular ejection fraction (LVEF; HFpEF) is a common type of heart failure in the elderly, and it typically represents advanced hypertensive heart disease. The left ventricle in patients with HFpEF is characterized by concentric remodeling, normal LVEF, but reduced left longitudinal shortening, and importantly diastolic dysfunction. Dyspnoe and fatigue in patients with HFpEF are due to impaired left ventricular filling with a rapid increase in filling pressures and the lack of an increase in stroke volume during exercise. The diagnosis of HFpEF requires the careful exclusion of non-cardiac causes of dyspnoe as well as cardiac causes of dyspnoe associated with preserved LVEF other than HFpEF, primarily coronary artery disease and valve disease. Then, the following findings are required to make a diagnosis of HFpEF: a non-dilated left ventricle with an LVEF >50% and the presence of a significant diastolic impairment, which can be assessed using invasive haemodynamics, echocardiography, natriuretic peptides, or a combination of these tools. In contrast to patients with heart failure and reduced LVEF there is still no established treatment for patients with HFpEF, which prolongs survival or reduces the rate of hospitalizations for heart failure. There is currently however intense research going on in this field, and results from large trials evaluating the effects of various interventions on clinical endpoints are expected within the next years.

  8. 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.

  9. Rain attenuation statistics over millimeter wave bands in South Korea

    Science.gov (United States)

    Shrestha, Sujan; Choi, Dong-You

    2017-01-01

    Rain induced degradations are significant for terrestrial microwave links operating at frequencies higher than 10 GHz. Paper presents analyses done on rain attenuation and rainfall data for three years between 2013 till 2015, in 3.2 km experimental link of 38 GHz and 0.1 km link at 75 GHz. The less link distance is maintained for 75 GHz operating frequency in order to have better recording of propagation effect as such attenuation induced by rain. OTT Parsivel is used for collection of rain rate database which show rain rate of about 50 mm/h and attenuation values of 20.89 and 28.55 dB are obtained at 0.01% of the time for vertical polarization under 38 and 75 GHz respectively. Prediction models, namely, ITU-R P. 530-16, Da Silva Mello, Moupfouma, Abdulrahman, Lin and differential equation approach are analyzed. This studies help to identify most suitable rain attenuation model for higher microwave bands. While applying ITU-R P. 530-16, the relative error margin of about 3%, 38% and 42% along with 80, 70, 61% were obtained in 0.1%, 0.01% and 0.001% of the time for vertical polarization under 38 and 75 GHz respectively. Interestingly, ITU-R P. 530-16 shows relatively closer estimation to measured rain attenuation at 75 GHz with relatively less error probabilities and additionally, Abdulrahman and ITU-R P. 530-16 results in better estimation to the measured rain attenuation at 38 GHz link. The performance of prominent rain attenuation models are judged with different error matrices as recommended by ITU-R P. 311-15. Furthermore, the efficacy of frequency scaling technique of rain attenuation between links distribution are also discussed. This study shall be useful for making good considerations in rain attenuation predictions for terrestrial link operating at higher frequencies.

  10. 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.

  11. Non-uniform recovery of left ventricular transmural mechanics in ST-segment elevation myocardial infarction

    Directory of Open Access Journals (Sweden)

    Wilansky Susan

    2010-08-01

    Full Text Available Abstract Background After a transient ischemic episode, the subendocardial region is more severely injured than outer subepicardial layers and may regain a proportionately greater degree of mechanical function in the longitudinal direction. We sought to explore left ventricular (LV transmural mechanics in patients with ST-segment elevation myocardial infarction (STEMI for determining the mechanism underlying recovery of global LV function after primary percutaneous coronary intervention (PCI. Methods A total of 42 patients (62 ± 11 years old, 71% male with a first STEMI underwent serial assessments of LV longitudinal, circumferential and radial strains (LS, CS and RS by selective tracking of subendocardial and subepicardial regions within 48 hours and a median of 5 months after PCI. LV mechanical parameters were compared with sixteen age and gender matched normal controls. Results In comparison with controls, endocardial and epicardial LS were markedly attenuated at 48 hours following PCI (P 5% following PCI was seen in 24 (57% patients and was associated with improvement in endocardial and epicardial LS (P Conclusions In patients with STEMI treated by PCI, the recovery of LV subendocardial shortening strain seen in the longitudinal direction underlies the improvement in LV global function despite persistent abnormalities in radial mechanics and wall motion score index.

  12. Matrix metalloproteinases and left ventricular function and structure in spinal cord injured subjects.

    Science.gov (United States)

    Schreiber, Roberto; Paim, Layde R; de Rossi, Guilherme; Matos-Souza, José R; Costa E Silva, Anselmo de A; Souza, Cristiane M; Borges, Mariane; Azevedo, Eliza R; Alonso, Karina C; Gorla, José I; Cliquet, Alberto; Nadruz, Wilson

    2014-11-01

    Subjects with spinal cord injury (SCI) exhibit impaired left ventricular (LV) diastolic function, which has been reported to be attenuated by regular physical activity. This study investigated the relationship between circulating matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs) and echocardiographic parameters in SCI subjects and the role of physical activity in this regard. Forty-two men with SCI [19 sedentary (S-SCI) and 23 physically-active (PA-SCI)] were evaluated by clinical, anthropometric, laboratory, and echocardiographic analysis. Plasmatic pro-MMP-2, MMP-2, MMP-8, pro-MMP-9, MMP-9, TIMP-1 and TIMP-2 levels were determined by enzyme-linked immunosorbent assay and zymography. PA-SCI subjects presented lower pro-MMP-2 and pro-MMP-2/TIMP-2 levels and improved markers of LV diastolic function (lower E/Em and higher Em and E/A values) than S-SCI ones. Bivariate analysis showed that pro-MMP-2 correlated inversely with Em and directly with E/Em, while MMP-9 correlated directly with LV mass index and LV end-diastolic diameter in the whole sample. Following multiple regression analysis, pro-MMP-2, but not physical activity, remained associated with Em, while MMP-9 was associated with LV mass index in the whole sample. These findings suggest differing roles for MMPs in LV structure and function regulation and an interaction among pro-MMP-2, diastolic function and physical activity in SCI subjects.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. Designing attenuators for total-body irradiation using virtual simulation.

    Science.gov (United States)

    Corns, R; Evans, M; Olivares, M; Dyke, L; Podgorsak, E B; Freeman, C R

    2000-01-01

    In total-body photon irradiation, the lungs are the most commonly shielded organ. Lung compensators are often designed by using high-energy portal films. Other organs, such as the kidneys and liver, are poorly visualized in portal films due to their unit-density composition. A computed tomography-based technique to design kidney and liver attenuators involves outlining these organs in a virtual simulation. The position and the shape of the attenuator are then determined from a digitally-reconstructed radiograph. Appropriate attenuator thickness is determined from measured transmission curves. This article provides a summary of this technique for total-body photon irradiation in a 4-MV photon beam.

  18. 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.

  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. Elemental analysis by means of X-ray attenuation measurements

    Science.gov (United States)

    Cesareo, Roberto; Giannini, Marino

    1980-03-01

    Radioactive sources of 109Cd, 241Am and 57Co were employed to measure the attenuation coefficient of biological materials such as whole blood, red blood cells, plasma, urine, water and of materials of interest for computed tomography, such as plexiglas, polyethylene, nylon, teflon, etc. The experimental errors range between 0.3% and 1%. A method is also presented which allows quantitative analysis of materials by measuring their attenuation coefficient at various monoenergetic X-ray energies. As an example, attenuation measurements at 60 keV and 122 keV were employed in order to determine the concentration of lead and copper in silver alloys.

  1. 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.

  2. The halting arrival of left-handed Z-DNA.

    Science.gov (United States)

    Gagna, C E; Lambert, W C

    2003-03-01

    Forty-nine years ago Watson and Crick proposed a double-stranded (ds-) model for DNA. This double helix has become an icon of molecular biology. Twenty-six years later, Rich accidently discovered Z-DNA, an exotic left-handed nucleic acid. For many years thereafter, this left-handed DNA was thought to be an artifact. DNA is no longer looked upon as a static molecule but rather an extremely dynamic structure in which different conformations are in equilibrium with each other. Many researchers have spent the last two decades characterizing this novel left-handed DNA structure. Now many investigators are beginning to accept the possibility that this novel ds-DNA conformation may play a significant in vivo role within eukaryotic and prokaryotic cells. However, more research needs to be performed before it is absolutely accepted by all in the scientific community.

  3. 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.

  4. 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.

  5. 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.

  6. Left-right correlation in coupled F-center defects.

    Science.gov (United States)

    Janesko, Benjamin G

    2016-08-07

    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. Implantation of left ventricular assist device complicated by undiagnosed thrombophilia.

    Science.gov (United States)

    Szarszoi, Ondrej; Maly, Jiri; Turek, Daniel; Urban, Marian; Skalsky, Ivo; Riha, Hynek; Maluskova, Jana; Pirk, Jan; Netuka, Ivan

    2012-01-01

    A patient with dilated cardiomyopathy and no history of thromboembolic events received a surgically implanted axial-flow left ventricular assist device. After implantation, transesophageal echocardiography revealed a giant thrombus on the lateral and anterior aspects of the left ventricle. The inflow cannula inserted through the apex of the left ventricle was not obstructed, and the device generated satisfactory blood flow. Laboratory screening for thrombophilia showed protein S deficiency, heterozygous factor V Leiden mutation, and heterozygous MTHFR C667T mutation. During the entire duration of circulatory support, no significant suction events were detected, and the patient was listed for heart transplantation. Ventricular assist device implantation can unmask previously undiagnosed thrombophilia; therefore, it should be necessary to identify thrombophilic patients before cardiac support implantation.

  8. Left Atrial Reverse Remodeling: Mechanisms, Evaluation, and Clinical Significance.

    Science.gov (United States)

    Thomas, Liza; Abhayaratna, Walter P

    2017-01-01

    The left atrium is considered a biomarker for adverse cardiovascular outcomes, particularly in patients with left ventricular diastolic dysfunction and atrial fibrillation in whom left atrial (LA) enlargement is of prognostic importance. LA enlargement with a consequent decrease in LA function represents maladaptive structural and functional "remodeling" that in turn promotes electrical remodeling and a milieu conducive for incident atrial fibrillation. Medical and nonmedical interventions may arrest this pathophysiologic process to the extent that subsequent reverse remodeling results in a reduction in LA size and improvement in LA function. This review examines cellular and basic mechanisms involved in LA remodeling, evaluates the noninvasive techniques that can assess these changes, and examines potential mechanisms that may initiate reverse remodeling.

  9. 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.

  10. 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.

  11. A novel hydrodynamic approach of drag-reducing polymers to improve left ventricular hypertrophy and aortic remodeling in spontaneously hypertensive rats.

    Science.gov (United States)

    Zhang, Xinlu; Wang, Xu; Hu, Feng; Zhou, Boda; Chen, Hai-Bin; Zha, Daogang; Liu, Yili; Guo, Yansong; Zheng, Lemin; Xiu, Jiancheng

    Drag-reducing polymers (DRPs), when added in minute concentrations, have been shown to decrease peripheral vascular resistance. In this study, the effect of DRPs on the hypertension-induced left ventricular hypertrophy and aortic remodeling was evaluated in spontaneously hypertensive rats (SHR). Male SHR and age-matched Wistar rats were divided into four groups and received intravenous injection of normal saline (NS) or DRPs. Body weight (BW), heart rate (HR) and systolic blood pressure (SBP) were measured. Echocardiography was used to evaluate the changes in left ventricle (LV) function and global wall motion. The LV and aorta were stained by hematoxylin and eosin. Cell size of cardiomyocytes and aortic medial thickness were evaluated for each section. The expression of endothelin-1 (ET-1) of LV and aorta was examined by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunohistochemistry. There was no significant difference in the increase of SBP among SHR + NS, SHR + 10DRP and SHR + 20DRP groups. SHR + NS group had markedly smaller left ventricular end-systolic diameter and left ventricular end-diastolic diameter but bigger anterior and posterior systolic wall thicknesses, while there was no significant difference in fractional shortening and ejection fraction. The cross-sectional areas (CSAs) of cardiomyocytes and the medial thickness of the aorta in SHR + 10 (ppm) DRP and SHR + 20 (ppm) DRP groups were significantly reduced compared with SHR + NS group. The expression of ET-1 in SHR + 10DRP and SHR + 20DRP groups was significantly attenuated. These results suggest that chronic treatment with DRPs can protect against left ventricular hypertrophy and aortic remodeling. DRPs may offer a new approach to the treatment of left ventricular hypertrophy and aortic remodeling caused by hypertension.

  12. Licking microstructure reveals rapid attenuation of neophobia.

    Science.gov (United States)

    Monk, Kevin J; Rubin, Benjamin D; Keene, Jennifer C; Katz, Donald B

    2014-03-01

    Many animals hesitate when initially consuming a novel food and increase their consumption of that food between the first and second sessions of access-a process termed attenuation of neophobia (AN). AN has received attention as a model of learning and memory; it has been suggested that plasticity resulting from an association of the novel tastant with "safe outcome" results in a change in the neural response to the tastant during the second session, such that consumption increases. Most studies have reported that AN emerges only an hour or more after the end of the first exposure to the tastant, consistent with what is known of learning-related plasticity. But these studies have typically measured consumption, rather than real-time behavior, and thus the possibility exists that a more rapidly developing AN remains to be discovered. Here, we tested this possibility, examining both consumption and individual lick times in a novel variant of a brief-access task (BAT). When quantified in terms of consumption, data from the BAT accorded well with the results of a classic one-bottle task-both revealed neophobia/AN specific to higher concentrations (for instance, 28mM) of saccharin. An analysis of licking microstructure, however, additionally revealed a real-time correlate of neophobia-an explicit tendency, similarly specific for 28-mM saccharin, to cut short the initial bout of licks in a single trial (compared with water). This relative hesitancy (i.e., the shortness of the first lick bout to 28-mM saccharin compared with water) that constitutes neophobia not only disappeared between sessions but also gradually declined in magnitude across session 1. These data demonstrate that the BAT accurately measures AN, and that aspects of AN-and the processes underlying familiarization-begin within minutes of the very first taste.

  13. Huge Left Atrium Accompanied by Normally Function- ing Prosthetic Valve

    Directory of Open Access Journals (Sweden)

    Feridoun Sabzi

    2015-10-01

    Full Text Available Giant left atria are defined as those measuring larger than 8 cm and are typically found in patients who have rheumatic mitral valve disease with severe regurgitation. Enlargement of the left atrium may create compression of the surrounding structures such as the esophagus, pulmonary veins, respiratory tract, lung, inferior vena cava, recurrent laryngeal nerve, and thoracic vertebrae and lead to dysphagia, respiratory dysfunction, peripheral edema, hoarse voice, or back pain. However, a huge left atrium is usually associated with rheumatic mitral valve disease but is very rare in a normally functioning prosthetic mitral valve, as was the case in our patient. A 46-year-old woman with a past medical history of mitral valve replacement and chronic atrial fibrillation was admitted to our hospital with a chief complaint of cough and shortness of breath, worsened in the last month. Physical examination showed elevated jugular venous pressure, respiratory distress, cardiac cachexia, heart failure, hepatomegaly, and severe edema in the legs. Chest radiography revealed an inconceivably huge cardiac sell-out. Transthoracic echocardiography demonstrated a huge left atrium, associated with thrombosis, and normal function of the prosthetic mitral valve. Cardiac surgery with left atrial exploration for the extraction of the huge thrombosis and De Vega annuloplasty for tricuspid regurgitation were carried out. The postoperative course was eventful due to right ventricular failure and low cardiac output syndrome; and after two days, the patient expired with multiple organ failure. Thorough literature review showed that our case was the largest left atrium (20 × 22 cm reported thus far in adults with a normal prosthetic mitral valve function.

  14. Attenuation of Landfill Leachate In Unsaturated Sandstone

    Science.gov (United States)

    Butler, A. P.; Brook, C.; Godley, A.; Lewin, K.; Young, C. P.

    Landfill leachate emanating from old "dilute and disperse" sites represents a potential (and in many cases actual) threat to the integrity of groundwater. Indeed, this concern has been included in EU legislation (80/86/EEC), where key contaminants (e.g. ammonia, various toxic organic compounds and heavy metals) are explicitly highlighted in terms of their impact on groundwater. In the UK, whilst there are a substantial number of unlined landfills sited on major aquifers, many of these are in locations where there is a substantial unsaturated zone. Thus, there exists the opportunity for the modification and attenuation of contaminants prior to it encountering the water table. An understanding of likely changes in leachate content and concentrations at such sites will enable a more comprehensive assessment of the potential risks and liabilities posed by such sites to be evaluated. The Burntstump landfill, situated 8 km north of Nottingham (UK), is sited on an outcrop of Sherwood sandstone. The fine friable sand has been quarried since the 1960s and the excavated volume used to store municipal waste. Filling at the site commenced in the mid 1970s and originally was unlined. In 1978 the first of what was to become a series of boreholes was installed within an area of roughly 5 m radius over one of the original waste cells. Cores of the waste and underlying sandstone were extracted and analysed for a range of physical and chemical parameters. The most recent set of analyses were obtained in 2000. The series of investigations therefore provide an important record of leachate migration and modification through the unsaturated zone for over twenty years. The progression of the leachate front is clearly delineated by the chloride concentration profile with an average velocity of around 1.6 m.yr-1. Combining this value with an average (and reasonably uniform) measured moisture content of about 7% gives a mean inter-granular specific discharge of 110 mm.yr-1. An interesting

  15. Remote postconditioning induced by brief pulmonary ischemia and reperfusion attenuates myocardial reperfusion injury in rabbits

    Institute of Scientific and Technical Information of China (English)

    TANG Yan-hua; XU Jian-jun; LI Ju-xiang; CHENG Xiao-shu

    2011-01-01

    Background The lung is one of the most important organs that are sensitive to ischemia. We hypothesized that remote postconditioning (RPostC) induced by brief occlusion and reperfusion of the pulmonary artery could attenuate myocardial reperfusion injury.Methods Thirty rabbits were randomized into three groups. Group ischemia-reperfusion (IR) (n=10) were anesthetized rabbits subjected to 30-minute occlusion of the left anterior descending coronary artery followed by 180-minute reperfusion. Group RPostC (n=10) had the left pulmonary artery blocked for five minutes followed by a 5-minute reperfusion, and the left anterior descending coronary artery (LAD) occluded for 30 minutes with a 180-minute reperfusion. Group L-Nw-nitro-L-arginine methylester (L-NAME) + RPostC (n=10) had the left pulmonary artery blocked for five minutes followed by a 5-minute reperfusion and intravenous infusion of L-NAME (10 mg/kg), and the LAD occluded for 30 minutes with a 180-minute reperfusion. Blood samples were taken for levels of creatine kinase (CK),superoxide dismutase (SOD) and malondialdehyde (MDA) at three different time points. At the end of the experiment,tissue samples of the infarcted region were harvested to calculate the cardiomyocyte apoptosis index (Al) by TUNEL. A piece of left and right lung tissue was harvested to evaluate the damage to the lung.Results After reperfusion for 180 minutes, the concentration of CK was lower in group RPostC, (4.79±0.27) U/ml, than that in group IR, (6.23±0.55) U/ml (P <0.01), and group L-NAME + RPsotC, (5.86±0.42) U/ml (P <0.01). The concentration of MDA was lower in group RPostC, (6.06±0.36) nmol/ml, than that in group IR, (11.41±0.91) nmol/ml (P <0.01), and group L-NAME + RPostC, (11.06±0.62) nmol/ml (P<0.01). The activity of SOD was higher in group RPostC,(242.34±25.02) U/ml, than that in group IR, (148.05±18.24) U/ml (P<0.01), and group L-NAME + RPostC, (160.66±9.55) U/ml (P<0.01). The apoptosis index was lower in

  16. Ebstein's Anomaly, Left Ventricular Noncompaction, and Sudden Cardiac Death

    Science.gov (United States)

    McGee, Michael; Warner, Luke; Collins, Nicholas

    2015-01-01

    Ebstein's anomaly is a congenital disorder characterized by apical displacement of the septal leaflet of the tricuspid valve. Ebstein's anomaly may be seen in association with other cardiac conditions, including patent foramen ovale, atrial septal defect, and left ventricular noncompaction (LVNC). LVNC is characterized by increased trabeculation within the left ventricular apex. Echocardiography is often used to diagnose LVNC; however, magnetic resonance (MR) imaging offers superior characterization of the myocardium. We report a case of sudden cardiac death in a patient with Ebstein's anomaly with unrecognized LVNC noted on post mortem examination with screening documenting the presence of LVNC in one of the patient's twin sons. PMID:26240764

  17. Absence of left circumflex with superdominant right coronary artery

    Science.gov (United States)

    Quijada-Fumero, Alejandro; Pimienta-González, Raquel; Rodriguez-Esteban, Marcos

    2014-01-01

    Congenital anomalies of coronary arteries are a group of diseases that are infrequently found. Their prevalence has been reported from 0.6% to 1.3%. Most clinical manifestations are benign and asymptomatic. Congenital absence of the left circumflex artery is a very rare congenital anomaly of the coronary circulation, and only a few cases have been reported in the literature. We report a case of a 51-year-old man who underwent a cardiac catheterisation. Coronary angiography showed a left anterior descending coronary artery with no circumflex and a dominant right coronary artery. PMID:25535241

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

    DEFF Research Database (Denmark)

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

    2010-01-01

    hemisphere damage. Here, we used a unique dual-site transcranial magnetic stimulation (TMS) approach to test whether the SMG in the right hemisphere contributes to modality-independent (i.e., auditory and visual) phonological decisions. To test task-specificity, we compared the effect of real or sham TMS...... the right or left SMG. Taken together, these findings provide converging evidence that the right SMG contributes to accurate and efficient phonological decisions in the healthy brain, with no evidence that the left and right SMG can compensate for one another during TMS. Our findings motivate detailed...

  19. Frequency of left-handedness among the Andhra Pradesh people.

    Science.gov (United States)

    Dronamraju, K R

    1975-01-01

    The percentages of left-handed people among the males and females of Andhra Pradesh tribals in India were found to be 15.49 and 7.79, and in Hindus 6.9 and 4.65. The difference between the sexes among tribals is significant. The tribal people studied were Koya Doras, Sugalis (or Lambadis), and Konda Reddis. It is suggested that similar quantitative studies of left-handedness should be made in other tribal and aboriginal populations before they are culturally comditioned to right-handedness.

  20. Warm Dark Matter in Low Scale Left-Right Theory

    OpenAIRE

    Nemevsek, Miha; Senjanovic, Goran; Zhang, Yue

    2012-01-01

    We investigate the viability of having dark matter in the minimal left-right symmetric theory. We find the lightest right-handed neutrino with a mass around keV as the only viable candidate consistent with a TeV scale of left-right symmetry. In order to account for the correct relic density with such low scales, the thermal overproduction of the dark matter in the early universe is compensated by a sufficient late entropy production due to late decay of heavier right-handed neutrinos. We poin...