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Sample records for strains undergoing neurulation

  1. Mechanics of neurulation: From classical to current perspectives on the physical mechanics that shape, fold, and form the neural tube.

    Vijayraghavan, Deepthi S; Davidson, Lance A

    2017-01-30

    Neural tube defects arise from mechanical failures in the process of neurulation. At the most fundamental level, formation of the neural tube relies on coordinated, complex tissue movements that mechanically transform the flat neural epithelium into a lumenized epithelial tube (Davidson, 2012). The nature of this mechanical transformation has mystified embryologists, geneticists, and clinicians for more than 100 years. Early embryologists pondered the physical mechanisms that guide this transformation. Detailed observations of cell and tissue movements as well as experimental embryological manipulations allowed researchers to generate and test elementary hypotheses of the intrinsic and extrinsic forces acting on the neural tissue. Current research has turned toward understanding the molecular mechanisms underlying neurulation. Genetic and molecular perturbation have identified a multitude of subcellular components that correlate with cell behaviors and tissue movements during neural tube formation. In this review, we focus on methods and conceptual frameworks that have been applied to the study of amphibian neurulation that can be used to determine how molecular and physical mechanisms are integrated and responsible for neurulation. We will describe how qualitative descriptions and quantitative measurements of strain, force generation, and tissue material properties as well as simulations can be used to understand how embryos use morphogenetic programs to drive neurulation. Birth Defects Research 109:153-168, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  2. Alteration of gene expression by alcohol exposure at early neurulation.

    Zhou, Feng C; Zhao, Qianqian; Liu, Yunlong; Goodlett, Charles R; Liang, Tiebing; McClintick, Jeanette N; Edenberg, Howard J; Li, Lang

    2011-02-21

    We have previously demonstrated that alcohol exposure at early neurulation induces growth retardation, neural tube abnormalities, and alteration of DNA methylation. To explore the global gene expression changes which may underline these developmental defects, microarray analyses were performed in a whole embryo mouse culture model that allows control over alcohol and embryonic variables. Alcohol caused teratogenesis in brain, heart, forelimb, and optic vesicle; a subset of the embryos also showed cranial neural tube defects. In microarray analysis (accession number GSM9545), adopting hypothesis-driven Gene Set Enrichment Analysis (GSEA) informatics and intersection analysis of two independent experiments, we found that there was a collective reduction in expression of neural specification genes (neurogenin, Sox5, Bhlhe22), neural growth factor genes [Igf1, Efemp1, Klf10 (Tieg), and Edil3], and alteration of genes involved in cell growth, apoptosis, histone variants, eye and heart development. There was also a reduction of retinol binding protein 1 (Rbp1), and de novo expression of aldehyde dehydrogenase 1B1 (Aldh1B1). Remarkably, four key hematopoiesis genes (glycophorin A, adducin 2, beta-2 microglobulin, and ceruloplasmin) were absent after alcohol treatment, and histone variant genes were reduced. The down-regulation of the neurospecification and the neurotrophic genes were further confirmed by quantitative RT-PCR. Furthermore, the gene expression profile demonstrated distinct subgroups which corresponded with two distinct alcohol-related neural tube phenotypes: an open (ALC-NTO) and a closed neural tube (ALC-NTC). Further, the epidermal growth factor signaling pathway and histone variants were specifically altered in ALC-NTO, and a greater number of neurotrophic/growth factor genes were down-regulated in the ALC-NTO than in the ALC-NTC embryos. This study revealed a set of genes vulnerable to alcohol exposure and genes that were associated with neural tube

  3. Draft Genome Sequences of Pseudomonas aeruginosa B3 Strains Isolated from a Cystic Fibrosis Patient Undergoing Antibiotic Chemotherapy

    Marvig, Rasmus Lykke; Jochumsen, Nicholas; Johansen, Helle Krogh

    2013-01-01

    Pseudomonas aeruginosa frequently establishes chronic infections in the airways of patients suffering from cystic fibrosis (CF). Here, we report the draft genome sequences of four P. aeruginosa B3 strains isolated from a chronically infected CF patient undergoing antibiotic chemotherapy.......Pseudomonas aeruginosa frequently establishes chronic infections in the airways of patients suffering from cystic fibrosis (CF). Here, we report the draft genome sequences of four P. aeruginosa B3 strains isolated from a chronically infected CF patient undergoing antibiotic chemotherapy....

  4. Prognostic value of strain and strain rate in the prediction of postoperative atrial fibrillation in patients undergoing coronary artery bypass grafting: a systematic literature review

    Leila Bigdelu

    2016-03-01

    Full Text Available Introduction: Atrial fibrillation (AF is a common dysrhythmia postoperatively after coronary artery bypass grafting (CABG. Myocardial strain and strain-rate imaging is used for the assessment of postoperative atrial fibrillation (POAF as a new echocardiographic method. Methods: PubMed and Scopus were searched thoroughly using the following search terms: (strain and strain rate AND (atrial fibrillation OR AF on March 2015 to find English articles in which the strain and strain-rate echocardiographic imaging had been used for the evaluation of AF in patients undergone CABG. Full text of the relevant papers was fully reviewed for data extraction.Result: Of overall 6 articles found in PubMed, 10 records found in Scopus and 4 articles found through reference list search, only 6 papers fully met the inclusion criteria for further assessment and data extraction. The results of strain and strain-rate assessment showed that in total of 542 patients undergoing CABG, POAF occurred in 106 patients. Studies showed that the reduction of left atrial (LA strain rate is correlated with AF. Consistently, the results of present review showed that LA strain and strain-rate in patients who developed AF postoperatively after CABG are significantly reduced, suggesting that strain and strain-rate could be a predictor of POAF.Conclusion: Based on the obtained results, strain and strain-rate is a suitable and accurate echocardiographic technique in the assessment of left atrial function , and it might be helpful to detect the patients who are at high risk of POAF.

  5. Planar strain analysis of liver undergoing microwave thermal ablation using x-ray CT.

    Weiss, Noam; Goldberg, S Nahum; Nissenbaum, Yitzhak; Sosna, Jacob; Azhari, Haim

    2015-01-01

    To study the planar strain effects in liver during microwave (MW) thermal ablation as a means for tracking tissue expansion and contraction as a method for improving ablation monitoring. 1.4 mm circular metallic markers were inserted into 16 ex-vivo bovine fresh liver specimens, that were subsequently ablated (with the markers inside the specimen) by 40 W of microwave energy, for 1, 2, 3, 6, and 10 min. The markers were tracked during the ablation using an x-ray CT scanner. Images were acquired every 5-10 s enabling determination of the markers' coordinates over time. The 2D principal strains were calculated for triangles formed by subgroups of three markers, and their planar strain index, Ω, was plotted vs time. In addition, the radial distance of the markers from the antenna was measured at the end of each ablation. Subsequently, the tissue was sliced parallel to the imaged planes and the ablation zone was traced and digitized. The average ablation radius was then computed and compared to the radial distance. The planar strain, Ω(t), profile demonstrated an ascending pattern until reaching a maximum at about 180 s, with a mean peak value (Ω = 1.31 ± 0.04) indicating tissue expansion. Thereafter, Ω progressively declined over the remaining duration of the ablation treatment, indicating tissue contraction. Furthermore, when plotting the ablation size vs time and the markers' mean radial distance vs time, it was found that the two curves intercepted at a time corresponding to the time of peak planar strain. By detecting the point of maximal planar strain in tissues during MW application, it is possible to noninvasively identify the location of the ablation zone front. The fact that the liver tissue proximal to the ablated zone expands during the first part of the treatment and then contracts when the ablation front reaches it, may serve as an index for monitoring the thermal treatment.

  6. Multi-scale finite element modeling allows the mechanics of amphibian neurulation to be elucidated

    Chen Xiaoguang; Wayne Brodland, G

    2008-01-01

    The novel multi-scale computational approach introduced here makes possible a new means for testing hypotheses about the forces that drive specific morphogenetic movements. A 3D model based on this approach is used to investigate neurulation in the axolotl (Ambystoma mexicanum), a type of amphibian. The model is based on geometric data from 3D surface reconstructions of live embryos and from serial sections. Tissue properties are described by a system of cell-based constitutive equations, and parameters in the equations are determined from physical tests. The model includes the effects of Shroom-activated neural ridge reshaping and lamellipodium-driven convergent extension. A typical whole-embryo model consists of 10 239 elements and to run its 100 incremental time steps requires 2 days. The model shows that a normal phenotype does not result if lamellipodium forces are uniform across the width of the neural plate; but it can result if the lamellipodium forces decrease from a maximum value at the mid-sagittal plane to zero at the plate edge. Even the seemingly simple motions of neurulation are found to contain important features that would remain hidden, they were not studied using an advanced computational model. The present model operates in a setting where data are extremely sparse and an important outcome of the study is a better understanding of the role of computational models in such environments

  7. Multi-scale finite element modeling allows the mechanics of amphibian neurulation to be elucidated

    Chen, Xiaoguang; Brodland, G. Wayne

    2008-03-01

    The novel multi-scale computational approach introduced here makes possible a new means for testing hypotheses about the forces that drive specific morphogenetic movements. A 3D model based on this approach is used to investigate neurulation in the axolotl (Ambystoma mexicanum), a type of amphibian. The model is based on geometric data from 3D surface reconstructions of live embryos and from serial sections. Tissue properties are described by a system of cell-based constitutive equations, and parameters in the equations are determined from physical tests. The model includes the effects of Shroom-activated neural ridge reshaping and lamellipodium-driven convergent extension. A typical whole-embryo model consists of 10 239 elements and to run its 100 incremental time steps requires 2 days. The model shows that a normal phenotype does not result if lamellipodium forces are uniform across the width of the neural plate; but it can result if the lamellipodium forces decrease from a maximum value at the mid-sagittal plane to zero at the plate edge. Even the seemingly simple motions of neurulation are found to contain important features that would remain hidden, they were not studied using an advanced computational model. The present model operates in a setting where data are extremely sparse and an important outcome of the study is a better understanding of the role of computational models in such environments.

  8. Neural tube defects – disorders of neurulation and related embryonic processes

    Copp, Andrew J.; Greene, Nicholas D. E.

    2014-01-01

    Neural tube defects (NTDs) are severe congenital malformations affecting 1 in every 1000 pregnancies. ‘Open’ NTDs result from failure of primary neurulation as seen in anencephaly, myelomeningocele (open spina bifida) and craniorachischisis. Degeneration of the persistently open neural tube in utero leads to loss of neurological function below the lesion level. ‘Closed’ NTDs are skin-covered disorders of spinal cord structure, ranging from asymptomatic spina bifida occulta to severe spinal cord tethering, and usually traceable to disruption of secondary neurulation. ‘Herniation’ NTDs are those in which meninges, with or without brain or spinal cord tissue, become exteriorised through a pathological opening in the skull or vertebral column (e.g. encephalocele and meningocele). NTDs have multifactorial etiology, with genes and environmental factors interacting to determine individual risk of malformation. While over 200 mutant genes cause open NTDs in mice, much less is known about the genetic causation of human NTDs. Recent evidence has implicated genes of the planar cell polarity signalling pathway in a proportion of cases. The embryonic development of NTDs is complex, with diverse cellular and molecular mechanisms operating at different levels of the body axis. Molecular regulatory events include the BMP and Sonic hedgehog pathways which have been implicated in control of neural plate bending. Primary prevention of NTDs has been implemented clinically following the demonstration that folic acid, when taken as a peri-conceptional supplement, can prevent many cases. Not all NTDs respond to folic acid, however, and adjunct therapies are required for prevention of this folic acid-resistant category. PMID:24009034

  9. Unjoined primary and secondary neural tubes: junctional neural tube defect, a new form of spinal dysraphism caused by disturbance of junctional neurulation.

    Eibach, Sebastian; Moes, Greg; Hou, Yong Jin; Zovickian, John; Pang, Dachling

    2017-10-01

    Primary and secondary neurulation are the two known processes that form the central neuraxis of vertebrates. Human phenotypes of neural tube defects (NTDs) mostly fall into two corresponding categories consistent with the two types of developmental sequence: primary NTD features an open skin defect, an exposed, unclosed neural plate (hence an open neural tube defect, or ONTD), and an unformed or poorly formed secondary neural tube, and secondary NTD with no skin abnormality (hence a closed NTD) and a malformed conus caudal to a well-developed primary neural tube. We encountered three cases of a previously unrecorded form of spinal dysraphism in which the primary and secondary neural tubes are individually formed but are physically separated far apart and functionally disconnected from each other. One patient was operated on, in whom both the lumbosacral spinal cord from primary neurulation and the conus from secondary neurulation are each anatomically complete and endowed with functioning segmental motor roots tested by intraoperative triggered electromyography and direct spinal cord stimulation. The remarkable feature is that the two neural tubes are unjoined except by a functionally inert, probably non-neural band. The developmental error of this peculiar malformation probably occurs during the critical transition between the end of primary and the beginning of secondary neurulation, in a stage aptly called junctional neurulation. We describe the current knowledge concerning junctional neurulation and speculate on the embryogenesis of this new class of spinal dysraphism, which we call junctional neural tube defect.

  10. Differences in sexual size dimorphism among farmed tilapia species and strains undergoing genetic improvement for body weight

    C.E. Lind

    2015-05-01

    Full Text Available Many tilapia (Oreochromis spp. farmers produce all-male populations because of the superior growth rate of males compared to females. To investigate differences in body weight at harvest of males and females among different tilapia strains, we analyzed data from 62,787 individuals collected from pedigreed breeding programs of O. niloticus (GIFT from Malaysia, the Abbassa line from Egypt, and the Akosombo line from Ghana, O. shiranus (the Bunda College-Domasi selection line, O. aureus (a selection line under development in Abbassa, Egypt, and a selection line from Israel and a synthetic selection line of Red tilapia under development in Jitra, Malaysia, derived from stock from Malaysia, Taiwan and Thailand (O. sp.. Mixed models were separately fitted to the data from each selection line. There was a significant sex effect in all strains (P < 0.001. A significant (P < 0.001 sex by generation interaction was observed in all strains (scale effect, not reversal of rankings, except Red tilapia and O. shiranus. Least squares means showed a large range in the magnitude of body weight differences between sexes across the seven strains. The largest percentage difference between females and males was in O. aureus from Egypt (female body weight was 52.2% that of males at harvest, whereas the smallest difference was observed in the GIFT strain of O. niloticus (female body weight 84.7% that of males. Female to male body weight percentages for Red tilapia, O. shiranus, Egypt O. niloticus, Israeli O. aureus and Ghana O. niloticus were 81.3, 81.0, 69.1, 61.7 and 61.0, respectively. We discuss the results in relation to the potential productivity improvements due to superior growth rates of all-male culture compared to mixed-sex culture in tilapia populations differing in the female to male body weight ratio.

  11. Three-dimensional thoracic aorta principal strain analysis from routine ECG-gated computerized tomography: feasibility in patients undergoing transcatheter aortic valve replacement.

    Satriano, Alessandro; Guenther, Zachary; White, James A; Merchant, Naeem; Di Martino, Elena S; Al-Qoofi, Faisal; Lydell, Carmen P; Fine, Nowell M

    2018-05-02

    Functional impairment of the aorta is a recognized complication of aortic and aortic valve disease. Aortic strain measurement provides effective quantification of mechanical aortic function, and 3-dimenional (3D) approaches may be desirable for serial evaluation. Computerized tomographic angiography (CTA) is routinely performed for various clinical indications, and offers the unique potential to study 3D aortic deformation. We sought to investigate the feasibility of performing 3D aortic strain analysis in a candidate population of patients undergoing transcatheter aortic valve replacement (TAVR). Twenty-one patients with severe aortic valve stenosis (AS) referred for TAVR underwent ECG-gated CTA and echocardiography. CTA images were analyzed using a 3D feature-tracking based technique to construct a dynamic aortic mesh model to perform peak principal strain amplitude (PPSA) analysis. Segmental strain values were correlated against clinical, hemodynamic and echocardiographic variables. Reproducibility analysis was performed. The mean patient age was 81±6 years. Mean left ventricular ejection fraction was 52±14%, aortic valve area (AVA) 0.6±0.3 cm 2 and mean AS pressure gradient (MG) 44±11 mmHg. CTA-based 3D PPSA analysis was feasible in all subjects. Mean PPSA values for the global thoracic aorta, ascending aorta, aortic arch and descending aorta segments were 6.5±3.0, 10.2±6.0, 6.1±2.9 and 3.3±1.7%, respectively. 3D PSSA values demonstrated significantly more impairment with measures of worsening AS severity, including AVA and MG for the global thoracic aorta and ascending segment (panalysis is clinically feasible from routine ECG-gated CTA. Appropriate reductions in PSSA were identified with increasing AS hemodynamic severity. Expanded study of 3D aortic PSSA for patients with various forms of aortic disease is warranted.

  12. Consequences of low or moderate prenatal ethanol exposures during gastrulation or neurulation for open field activity and emotionality in mice.

    Schambra, Uta B; Nunley, Kevin; Harrison, Theresa A; Lewis, C Nicole

    In a previous study we used a mouse model for ethanol exposure during gastrulation or neurulation to investigate the effects of modest and occasional human drinking during the 3rd or 4th week of pregnancy (Schambra et al., 2015). Pregnant C57Bl/6J mice were treated by gavage during gastrulation on gestational day (GD) 7 or neurulation on GD8 with 2 doses 4h apart of either 2.4 or 2.9g ethanol/kg body weight, resulting in peak blood ethanol concentrations (BECs) of 104 and 177mg/dl, respectively. We found that mice exposed to the low dose on either day were significantly delayed in their neonatal sensorimotor development. In the present study, we tested the same cohort of mice in an open field as juveniles on postnatal day (PD) 23-25 and as young adults on PD65-67 for prenatal ethanol effects on exploration and emotionality with measures of activity, rearing, grooming and defecation. We evaluated the effects of dose, sex, day of treatment and day of birth by multiple regression analyses. We found that, compared to the respective gavage controls, juvenile mice that had been prenatally exposed to the low BEC on either GD7 or GD8 were significantly hypoactive on the first 2 test days, reared significantly more on the last 2 test days, and groomed and defecated significantly more on all 3 test days. Only mice that had been treated on GD7 remained hypoactive as adults. Juvenile mice prenatally exposed to the moderate BEC on GD7 groomed significantly more, while those exposed on GD8 reared and defecated significantly more. Sex differences were highly significant in adult control mice, with control males less active and more emotional than females. Similar, but smaller, sex differences were also evident in adults exposed to ethanol prenatally. Persistence into later life of a deleterious effect of premature birth (i.e., birth on GD19 rather than GD20) on weight and behavior was not consistently supported by these data. Importantly, mice shown previously to be delayed in

  13. Prognostic and Added Value of Two-Dimensional Global Longitudinal Strain for Prediction of Survival in Patients with Light Chain Amyloidosis Undergoing Autologous Hematopoietic Cell Transplantation.

    Pun, Shawn C; Landau, Heather J; Riedel, Elyn R; Jordan, Jonathan; Yu, Anthony F; Hassoun, Hani; Chen, Carol L; Steingart, Richard M; Liu, Jennifer E

    2018-01-01

    Autologous hematopoietic cell transplantation (HCT) is a first-line therapy for prolonging survival in patients with light-chain (AL) amyloidosis. Cardiac involvement is the most important determinant of survival. However, patients with advanced cardiac involvement have often been excluded from HCT because of high risk for transplantation-related mortality and poor overall survival. Whether baseline left ventricular global longitudinal strain (GLS) can provide additional risk stratification and predict survival after HCT in this high-risk population remains unclear. The aim of this study was to evaluate the prognostic implication of baseline GLS and the added value of GLS beyond circulating cardiac biomarkers for risk stratification in patients with AL amyloidosis undergoing HCT. Eighty-two patients with newly diagnosed AL amyloidosis who underwent upfront HCT between January 2007 and April 2014 were included in the study. Clinical, echocardiographic, and serum cardiac biomarker data were collected at baseline and 12 months following HCT. GLS measurements were performed using a vendor-independent offline system. The median follow-up time for survivors was 58 months. Sixty-four percent of patients were in biomarker-based Mayo stage II or III. GLS, brain natriuretic peptide, troponin, and mitral E/A ratio were identified as the strongest predictors of survival (P value that best discriminated survivors from nonsurvivors, and the application of this cutoff value provided further mortality risk stratification within each Mayo stage. GLS is a strong predictor of survival in patients with AL amyloidosis undergoing HCT, potentially providing incremental value over serum cardiac biomarkers for risk stratification. GLS should be considered as a standard parameter along with serum cardiac biomarkers when evaluating eligibility for HCT or other investigational therapies. Copyright © 2017 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

  14. Speckle tracking echocardiography derived 2-dimensional myocardial strain predicts left ventricular function and mass regression in aortic stenosis patients undergoing aortic valve replacement.

    Staron, Adam; Bansal, Manish; Kalakoti, Piyush; Nakabo, Ayumi; Gasior, Zbigniew; Pysz, Piotr; Wita, Krystian; Jasinski, Marek; Sengupta, Partho P

    2013-04-01

    Regression of left ventricular (LV) mass in severe aortic stenosis (AS) following aortic valve replacement (AVR) reduces the potential risk of sudden death and congestive heart failure associated with LV hypertrophy. We investigated whether abnormalities of resting LV deformation in severe AS can predict the lack of regression of LV mass following AVR. Two-dimensional speckle tracking echocardiography (STE) was performed in a total of 100 subjects including 60 consecutive patients with severe AS having normal LV ejection fraction (EF > 50 %) and 40 controls. STE was performed preoperatively and at 4 months following AVR, including longitudinal strain assessed from the apical 4-chamber and 2-chamber views and the circumferential and rotational mechanics measured from the apical short axis view. In comparison with controls, the patients with AS showed a significantly lower LV longitudinal (p regression (>10 %) following AVR. In conclusion, STE can quantify the burden of myocardial dysfunction in patients with severe AS despite the presence of normal LV ejection fraction. Furthermore, resting abnormalities in circumferential strain at LV apex is related with a hemodynamic milieu associated with the lack of LV mass regression during short-term follow up after AVR.

  15. Isolation, identification and in silico analysis of alpha-amylase gene of Aspergillus niger strain CSA35 obtained from cassava undergoing spoilage

    Oghenetega J. Avwioroko

    2018-07-01

    Full Text Available In this investigation, a gene (CDF_Amyl encoding extracellular α-amylase in Aspergillus niger strain CSA35 associated with cassava spoilage was amplified using specific primers and characterized in silico. The gene had a partial nucleotide sequence of 968 bp and encoded a protein of 222 aa residues with a molecular weight and isoelectric point of 25.13 kDa and 4.17, respectively. Its catalytic site was located in the active site domain. BLASTp analysis showed that the protein primary sequence of the α-amylase gene had 98% and 99% homologies with the α-amylase of A. niger and A. oryzae RIB40, respectively. The gene is more closely related to α-amylase genes from fungi than to bacterial, plant, or animal α-amylase genes. Restriction mapping of the gene showed it can be digested with restriction enzymes like NcoI, PstI, SmaI, and BcLI among others but not with EcoRI and EcoRV. Its protein product had a hydrophobicity score of − 0.43 but no transmembrane helix. The CDF_Amyl protein was subcellularly localized in the secretory pathway, an indication of its release into extracellular space after secretion. Also, the 3D structure of the CDF-Amyl protein was barrel-shaped with domains characteristic of α-amylases. The encoded α-amylase Vmax is 6.90 U/mg protein and Km is 6.70 mg/ml. It was concluded that the unique characteristics of the CDF_Amyl gene and its deduced protein could find applications in biotechnological, food and pharmaceutical industries where cloning and further modification of this gene would be required for product development and improvement.

  16. Synergistic Utility of Brain Natriuretic Peptide and Left Ventricular Global Longitudinal Strain in Asymptomatic Patients With Significant Primary Mitral Regurgitation and Preserved Systolic Function Undergoing Mitral Valve Surgery.

    Alashi, Alaa; Mentias, Amgad; Patel, Krishna; Gillinov, A Marc; Sabik, Joseph F; Popović, Zoran B; Mihaljevic, Tomislav; Suri, Rakesh M; Rodriguez, L Leonardo; Svensson, Lars G; Griffin, Brian P; Desai, Milind Y

    2016-07-01

    In asymptomatic patients with ≥3+ mitral regurgitation and preserved left ventricular (LV) ejection fraction who underwent mitral valve surgery, we sought to discover whether baseline LV global longitudinal strain (LV-GLS) and brain natriuretic peptide provided incremental prognostic utility. Four hundred and forty-eight asymptomatic patients (61±12 years and 69% men) with ≥3+ primary mitral regurgitation and preserved left ventricular ejection fraction, who underwent mitral valve surgery (92% repair) at our center between 2005 and 2008, were studied. Baseline clinical and echocardiographic data (including LV-GLS using Velocity Vector Imaging, Siemens, PA) were recorded. The Society of Thoracic Surgeons score was calculated. The primary outcome was death. Mean Society of Thoracic Surgeons score, left ventricular ejection fraction, mitral effective regurgitant orifice, indexed LV end-diastolic volume, and right ventricular systolic pressure were 4±1%, 62±3%, 0.55±0.2 cm(2), 58±13 cc/m(2), and 37±15 mm Hg, respectively. Forty-five percent of patients had flail. Median log-transformed BNP and LV-GLS were 4.04 (absolute brain natriuretic peptide: 60 pg/dL) and -20.7%. At 7.7±2 years, death occurred in 41 patients (9%; 0% at 30 days). On Cox analysis, a higher Society of Thoracic Surgeons score (hazard ratio 1.55), higher baseline right ventricular systolic pressure (hazard ratio 1.11), more abnormal LV-GLS (hazard ratio 1.17), and higher median log-transformed BNP (hazard ratio 2.26) were associated with worse longer-term survival (all Pright ventricular systolic pressure) provided incremental prognostic utility (χ(2) for longer-term mortality increased from 31-47 to 61; Pleft ventricular ejection fraction who underwent mitral valve surgery, brain natriuretic peptide and LV-GLS provided synergistic risk stratification, independent of established factors. © 2016 American Heart Association, Inc.

  17. Deficits in spatial learning and memory in adult mice following acute, low or moderate levels of prenatal ethanol exposure during gastrulation or neurulation.

    Schambra, Uta B; Lewis, C Nicole; Harrison, Theresa A

    2017-07-01

    Debate continues on the merits of strictly limiting alcohol consumption during all of pregnancy, and whether "safe" consumption levels and/or times exist. Only a relatively few experimental studies have been conducted that limit the timing of exposure to specific events during development and the exposure level to one that might model sporadic, incidental drinking during pregnancy. In the present study, the effects of two acute gavage exposures to low and moderate levels of ethanol (peak blood ethanol concentrations (BEC) of 104 and 177mg/dl, respectively) either during gastrulation on gestational day (GD) 7 (at GD7:0h and GD7:4h) or during neurulation on GD8 (at GD8:6h and GD8:10h) on the spatial learning and memory abilities of adult mice in the radial arm maze (RAM) were examined. Mice were selected from a prenatal ethanol exposure (PAE) cohort that had been tested as neonates for their sensorimotor development (Schambra et al., 2015) and as juveniles and young adults for open field activity levels and emotionality (Schambra et al., 2016). Mice exposed on either of the two gestational days to acute, low or moderate levels of ethanol were deficient in overall performance in the RAM in adulthood. Importantly, mice in ethanol exposed groups took longer to reach criterion in the RAM, and many mice in these groups failed to do so after 48 trials when testing was terminated. Exposure to a low level of ethanol on either GD7 or GD8, or a moderate level on GD7, resulted in significant impairment in spatial reference (long-term) memory, while only mice exposed on GD7 to the low level of ethanol were significantly impaired in spatial working (short-term) memory. Mice exposed to the low ethanol level on either day had significantly shorter response latencies, which may reflect impairment of processes related to response inhibition or executive attention in these mice. For all measures, distributions of individual scores revealed a relatively small subset of mice in each PAE

  18. Strain gradient effects in surface roughening

    Borg, Ulrik; Fleck, N.A.

    2007-01-01

    evidence for strain gradient effects. Numerical analyses of a bicrystal undergoing in-plane tensile deformation are also studied using a strain gradient crystal plasticity theory and also by using a strain gradient plasticity theory for an isotropic solid. Both theories include an internal material length...

  19. A nonaffine network model for elastomers undergoing finite deformations

    Davidson, Jacob D.; Goulbourne, N. C.

    2013-08-01

    In this work, we construct a new physics-based model of rubber elasticity to capture the strain softening, strain hardening, and deformation-state dependent response of rubber materials undergoing finite deformations. This model is unique in its ability to capture large-stretch mechanical behavior with parameters that are connected to the polymer chemistry and can also be easily identified with the important characteristics of the macroscopic stress-stretch response. The microscopic picture consists of two components: a crosslinked network of Langevin chains and an entangled network with chains confined to a nonaffine tube. These represent, respectively, changes in entropy due to thermally averaged chain conformations and changes in entropy due to the magnitude of these conformational fluctuations. A simple analytical form for the strain energy density is obtained using Rubinstein and Panyukov's single-chain description of network behavior. The model only depends on three parameters that together define the initial modulus, extent of strain softening, and the onset of strain hardening. Fits to large stretch data for natural rubber, silicone rubber, VHB 4905 (polyacrylate rubber), and b186 rubber (a carbon black-filled rubber) are presented, and a comparison is made with other similar constitutive models of large-stretch rubber elasticity. We demonstrate that the proposed model provides a complete description of elastomers undergoing large deformations for different applied loading configurations. Moreover, since the strain energy is obtained using a clear set of physical assumptions, this model may be tested and used to interpret the results of computer simulation and experiments on polymers of known microscopic structure.

  20. Strain-induced internal fibrillation in looped aramid filaments

    Pauw, Brian Richard; Vigild, Martin Etchells; Mortensen, Kell

    2010-01-01

    in the scattering pattern is observed. One model capable of describing the intensity is a model of stacked cylinders. These cylinders could be part of the fibrillar structure present in the PPTA fibres, which consist of cylinder- to tape-like objects, the presence of which is supported by SEM images. One...... hypothetical physical interpretation presented here for the appearance of a regular internal structure is the occurrence of fibrillar separation in regions undergoing axially compressive strain, and the appearance of strain relief/slip planes between packs of fibrils in regions undergoing tensile strain...

  1. A Review: Carbon Nanotube-Based Piezoresistive Strain Sensors

    Waris Obitayo

    2012-01-01

    Full Text Available The use of carbon nanotubes for piezoresistive strain sensors has acquired significant attention due to its unique electromechanical properties. In this comprehensive review paper, we discussed some important aspects of carbon nanotubes for strain sensing at both the nanoscale and macroscale. Carbon nanotubes undergo changes in their band structures when subjected to mechanical deformations. This phenomenon makes them applicable for strain sensing applications. This paper signifies the type of carbon nanotubes best suitable for piezoresistive strain sensors. The electrical resistivities of carbon nanotube thin film increase linearly with strain, making it an ideal material for a piezoresistive strain sensor. Carbon nanotube composite films, which are usually fabricated by mixing small amounts of single-walled or multiwalled carbon nanotubes with selected polymers, have shown promising characteristics of piezoresistive strain sensors. Studies also show that carbon nanotubes display a stable and predictable voltage response as a function of temperature.

  2. Specialised care in patients undergoing pancreatoduodenectomy

    Tol, J.A.M.G.

    2014-01-01

    This thesis studies the controversies in the management of patients with pancreatic cancer undergoing pancreatoduodenectomy and determines different factors that will improve this management and thereby the postoperative outcomes. The studies were performed in both the pre-, peri- and postoperative

  3. Antibiotic prophylaxis for patients undergoing elective endoscopic ...

    Antibiotic prophylaxis for patients undergoing elective endoscopic retrograde cholangiopancreatography. M Brand, D Bisoz. Abstract. Background. Antibiotic prophylaxis for endoscopic retrograde cholangiopancreatography (ERCP) is controversial. We set out to assess the current antibiotic prescribing practice among ...

  4. Strain-Modulated Epitaxy

    Brown, April

    1999-01-01

    Strain-Modulated Epitaxy (SME) is a novel approach, invented at Georgia Tech, to utilize subsurface stressors to control strain and therefore material properties and growth kinetics in the material above the stressors...

  5. Hamstring strain - aftercare

    Pulled hamstring muscle; Sprain - hamstring ... There are 3 levels of hamstring strains: Grade 1 -- mild muscle strain or pull Grade 2 -- partial muscle tear Grade 3 -- complete muscle tear Recovery time depends ...

  6. Homocysteine interference in neurulation: a chick embryo model.

    Afman, L.A.; Blom, H.J.; Put, N.M.J. van der; Straaten, H.W.M. van

    2003-01-01

    BACKGROUND: Periconceptional folic acid supplementation reduces the occurrence and recurrence risk of neural tube defects (NTD). Mothers of children with NTD have elevated plasma homocysteine levels. Administering homocysteine to chick embryos is reported to cause 27% NTD. Therefore, elevated plasma

  7. Teratogenic effects of retinoic acid on neurulation in mice embryos.

    Nobakht, M; Zirak, A; Mehdizadeh, M; Tabatabaeei, P

    2006-02-21

    Retinoic acids (RA) are natural chemicals that exert a hormone-like activity and a variety of biological effects on early development of mouse. In this study, the probable teratogenic effects of RA on CNS have been investigated in pregnant mice (n = 20) divided into four groups: (1) untreated controls, (2) controls which received a single dose of DMSO, (3) a group that received 40 mg/kg, and (4) a group that received 60 mg/kg of all-trans RA in DMSO, respectively on the eighth day of gestation. Embryos whose dams had received 40 and 60 mg/kg doses of RA, showed malformations and decreased size. At 40 mg/kg dosage level, 50% of the embryos had closed neural tubes while at 60 mg/kg dosage level the neural tube failed to close. The neuroblast mantle layers were disorganized in the 40 mg/kg and even more in the 60 mg/kg exposed group compared to the controls. In mitosis, the density of chromatin was increased in the 60 mg/kg dose group. Compared to controls the 40 and 60 mg/kg dose groups of RA treated dams decreases in the luminal longitudinal and internal measures were observed. Also the thickness of ventricular, mantle and marginal layers was smaller. Wide intercellular spaces due to the degenerated cells at high doses of RA as well as an accumulation of intercellular fluid were observed. Therefore, the wedge shape of neuroepithelium was abolished, preventing the elevation of the neural wall.

  8. Inhibition of transmethylation disturbs neurulation in chick embryos.

    Afman, L.A.; Blom, H.J.; Drittij, M.J.; Brouns, M.R.; Straaten, H.W.M. van

    2005-01-01

    Periconceptional folic acid supplementation can reduce the occurrence of neural tube defects. A low folate status will result in reduced remethylation of homocysteine (Hcy) to methionine and, subsequently, in a rise of Hcy levels. Indeed, elevated Hcy concentrations have been reported in mothers of

  9. A strain gauge

    2016-01-01

    The invention relates to a strain gauge of a carrier layer and a meandering measurement grid positioned on the carrier layer, wherein the strain gauge comprises two reinforcement members positioned on the carrier layer at opposite ends of the measurement grid in the axial direction....... The reinforcement members are each placed within a certain axial distance to the measurement grid with the axial distance being equal to or smaller than a factor times the grid spacing. The invention further relates to a multi-axial strain gauge such as a bi-axial strain gauge or a strain gauge rosette where each...... of the strain gauges comprises reinforcement members. The invention further relates to a method for manufacturing a strain gauge as mentioned above....

  10. Modelling non-uniform strain distributions in aerospace composites using fibre Bragg gratings

    Rajabzadehdizaji, Aydin; Groves, R.M.; Hendriks, R.C.; Heusdens, R.; Chung, Y.; Jin, W.; Lee, B.; Canning, J.; Nakamura, K.; Yuan, L.

    2017-01-01

    In this paper the behaviour of fibre Bragg grating (FBG) sensors under non-uniform strain distributions was analysed. Using the fundamental matrix approach, the length of the FBG sensor was discretised, with each segment undergoing different strain values. FBG sensors that are embedded inside

  11. Uniaxial tension test on Rubber at constant true strain rate

    Sourne H.L.

    2012-08-01

    Full Text Available Elastomers are widely used for damping parts in different industrial contexts because of their remarkable dissipation properties. Indeed, they can undergo severe mechanical loading conditions, i.e., high strain rates and large strains. Nevertheless, the mechanical response of these materials can vary from purely rubber-like to glassy depending on the strain rate undergone. Classically, uniaxial tension tests are made in order to find a relation between the stress and the strain in the material at various strain rates. However, even if the strain rate is searched to be constant, it is the nominal strain rate that is considered. Here we develop a test at constant true strain rate, i.e. the strain rate that is experienced by the material. In order to do such a test, the displacement imposed by the machine is an exponential function of time. This test has been performed with a high speed hydraulic machine for strain rates between 0.01/s and 100/s. A specific specimen has been designed, yielding a uniform strain field (and so a uniform stress field. Furthermore, an instrumented aluminum bar has been used to take into account dynamic effects in the measurement of the applied force. A high speed camera enables the determination of strain in the sample using point tracking technique. Using this method, the stress-strain curve of a rubber-like material during a loading-unloading cycle has been determined, up to a stretch ratio λ = 2.5. The influence of the true strain rate both on stiffness and on dissipation of the material is then discussed.

  12. Three dimensional strained semiconductors

    Voss, Lars; Conway, Adam; Nikolic, Rebecca J.; Leao, Cedric Rocha; Shao, Qinghui

    2016-11-08

    In one embodiment, an apparatus includes a three dimensional structure comprising a semiconductor material, and at least one thin film in contact with at least one exterior surface of the three dimensional structure for inducing a strain in the structure, the thin film being characterized as providing at least one of: an induced strain of at least 0.05%, and an induced strain in at least 5% of a volume of the three dimensional structure. In another embodiment, a method includes forming a three dimensional structure comprising a semiconductor material, and depositing at least one thin film on at least one surface of the three dimensional structure for inducing a strain in the structure, the thin film being characterized as providing at least one of: an induced strain of at least 0.05%, and an induced strain in at least 5% of a volume of the structure.

  13. Strain measurement technique

    1987-01-01

    The 10 contributions are concerned with selected areas of application, such as strain measurements in wood, rubber/metal compounds, sets of strain measurements on buildings, reinforced concrete structures without gaps, pipes buried in the ground and measurements of pressure fluctuations. To increase the availability and safety of plant, stress analyses were made on gas turbine rotors with HT-DMS or capacitive HT-DMS (high temperature strain measurements). (DG) [de

  14. Genetic transformation of Bacillus strains close to bacillus subtilis and isolated from the soil

    Van, C.K.; Kuzin, Yu.Yu.; Kozlovskii, Yu.E.; Prozorov, A.A.

    1986-01-01

    Chromosomal and plasmid transformation was found in five out of 118 Bacillus strains, close or identical to Bacillus subtilis, and isolated from soil in Moscow or in the Moscow district. The efficiency of transformation in these strains was lower than that in derivatives of Bac. subtilis strain 168. In these strains the ability to undergo transformation was dependent on the rate of sporulation and the presence of restrictases. As in the case of Bac. subtilis 168 the strains isolated may be used as models in genetic transformation studies on Bac. subtilis

  15. Strained Silicon Photonics

    Ralf B. Wehrspohn

    2012-05-01

    Full Text Available A review of recent progress in the field of strained silicon photonics is presented. The application of strain to waveguide and photonic crystal structures can be used to alter the linear and nonlinear optical properties of these devices. Here, methods for the fabrication of strained devices are summarized and recent examples of linear and nonlinear optical devices are discussed. Furthermore, the relation between strain and the enhancement of the second order nonlinear susceptibility is investigated, which may enable the construction of optically active photonic devices made of silicon.

  16. Lattice strain measurements on sandstones under load using neutron diffraction

    Frischbutter, A.; Neov, D.; Scheffzük, Ch.; Vrána, M.; Walther, K.

    2000-11-01

    Neutron diffraction methods (both time-of-flight- and angle-dispersive diffraction) are applied to intracrystalline strain measurements on geological samples undergoing uniaxial increasing compressional load. The experiments were carried out on Cretaceous sandstones from the Elbezone (East Germany), consisting of >95% quartz which are bedded but without crystallographic preferred orientation of quartz. From the stress-strain relation the Young's modulus for our quartz sample was determined to be (72.2±2.9) GPa using results of the neutron time-of-flight method. The influence of different kinds of bedding in sandstones (laminated and convolute bedding) could be determined. We observed differences of factor 2 (convolute bedding) and 3 (laminated bedding) for the elastic stiffness, determined with angle dispersive neutron diffraction (crystallographic strain) and with strain gauges (mechanical strain). The data indicate which geological conditions may influence the stress-strain behaviour of geological materials. The influence of bedding on the stress-strain behaviour of a laminated bedded sandstone was indicated by direct residual stress measurements using neutron time-of-flight diffraction. The measurements were carried out six days after unloading the sample. Residual strain was measured for three positions from the centre to the periphery and within two radial directions of the cylinder. We observed that residual strain changes from extension to compression in a different manner for two perpendicular directions of the bedding plane.

  17. A strain gauge

    2017-01-01

    The invention relates to a strain gauge of a carrier layer and a meandering measurement grid (101) positioned on the carrier layer, wherein the measurement grid comprises a number of measurement grid sections placed side by side with gaps in between, and a number of end loops (106) interconnecting...... relates to a method for manufacturing a strain gauge as mentioned above....

  18. Aspirin in patients undergoing noncardiac surgery

    Devereaux, P J; Mrkobrada, Marko; Sessler, Daniel I

    2014-01-01

    BACKGROUND: There is substantial variability in the perioperative administration of aspirin in patients undergoing noncardiac surgery, both among patients who are already on an aspirin regimen and among those who are not. METHODS: Using a 2-by-2 factorial trial design, we randomly assigned 10......,010 patients who were preparing to undergo noncardiac surgery and were at risk for vascular complications to receive aspirin or placebo and clonidine or placebo. The results of the aspirin trial are reported here. The patients were stratified according to whether they had not been taking aspirin before...... the study (initiation stratum, with 5628 patients) or they were already on an aspirin regimen (continuation stratum, with 4382 patients). Patients started taking aspirin (at a dose of 200 mg) or placebo just before surgery and continued it daily (at a dose of 100 mg) for 30 days in the initiation stratum...

  19. Platelet activation in outpatients undergoing esophagogastroduodenoscopy

    Sagripanti, A.; Polloni, A.; Materazzi, F.; Ferdeghini, M.; Pinori, E.; Bianchi, R.

    1989-01-01

    To evaluate the influence of emotional stress on platelet function mesured by radioimmunoassay in plasma two platelet factor 4, in a series of outpatients undergoing esophagogastroduodenoscopy for upper digestive complaints has been measured. The plasma levels of β-thromboglobulin and platelet factor 4, determined just before the instrumental examination, were significantly more elevated as compared to basal values, checked a week later. These results provide evidence of enhanced in vivo platelet release reaction during emotional stress

  20. Coagulation management in patients undergoing neurosurgical procedures.

    Robba, Chiara; Bertuetti, Rita; Rasulo, Frank; Bertuccio, Alessando; Matta, Basil

    2017-10-01

    Management of coagulation in neurosurgical procedures is challenging. In this contest, it is imperative to avoid further intracranial bleeding. Perioperative bleeding can be associated with a number of factors, including anticoagulant drugs and coagulation status but is also linked to the characteristic and the site of the intracranial disorder. The aim of this review will be to focus primarily on the new evidence regarding the management of coagulation in patients undergoing craniotomy for neurosurgical procedures. Antihemostatic and anticoagulant drugs have shown to be associated with perioperative bleeding. On the other hand, an increased risk of venous thromboembolism and hypercoagulative state after elective and emergency neurosurgery, in particular after brain tumor surgery, has been described in several patients. To balance the risk between thrombosis and bleeding, it is important to be familiar with the perioperative changes in coagulation and with the recent management guidelines for anticoagulated patients undergoing neurosurgical procedures, in particular for those taking new direct anticoagulants. We have considered the current clinical trials and literature regarding both safety and efficacy of deep venous thrombosis prophylaxis in the neurosurgical population. These were mainly trials concerning both elective surgical and intensive care patients with a poor grade intracranial bleed or multiple traumas with an associated severe traumatic brain injury (TBI). Coagulation management remains a major issue in patients undergoing neurosurgical procedures. However, in this field of research, literature quality is poor and further studies are necessary to identify the best strategies to minimize risks in this group of patients.

  1. Increased Resistance of Skin Flora to Antimicrobial Prophylaxis in Patients Undergoing Hip Revision Arthroplasty.

    Mühlhofer, Heinrich M L; Deiss, Lukas; Mayer-Kuckuk, Philipp; Pohlig, Florian; Harrasser, Norbert; Lenze, Ulrich; Gollwitzer, Hans; Suren, Christian; Prodinger, Peter; VON Eisenhart-Rothe, Rüdiger; Schauwecker, Johannes

    2017-01-01

    Prosthetic joint infection (PJI) remains a major complication after total joint replacement and is the primary indication for revision arthroplasty. Specifically, coagulase-negative Staphylococci (CNS) can cause low-grade infections. Despite the use of cephalosporin-based antimicrobial prophylaxis (AMP) and antiseptic treatment at the surgical site, evidence suggests that a significant number of cases of dermal CNS results in low-grade PJI. Thus, this study examined the bacterial colonization and resistance patterns at the surgical site. We hypothesized that the bacteria developed resistance to antibiotics that are frequently used in primary and revision total hip arthroplasty (THA) procedures. Ninety patients, including 63 primary and 27 revision THA patients, were enrolled in this study. For each patient, a single swab of the skin at the surgical site was subjected to clinical microbiology to assess bacterial colonization. Furthermore, resistance to a sentinel panel of antibiotics (benzylpenicillin, erythromycin, tetracycline, oxacillin, fusidic acid, clindamycin, gentamicin, levofloxacin/moxifloxacin, rifampicin, linezolid and vancomycin) was tested. In 96.7% of the patients, at least one bacterial strain was identified at the surgical site, with CNS strains comprising 93.1% of the total. The sentinel panel showed that 30.7% of the CNS strains exhibited maximal resistance to oxacillin, a commonly used cephalosporin. Additionally, oxacillin resistance increased 1.9-fold (p=0.042) between primary and revision THA. Notably, 8.1% of the CNS stains found on patients undergoing primary THA were resistant to gentamicin, an aminoglycoside, and this rate increased 4.7-fold (p=0.001) for patients undergoing revision THA. CNS strains have significant resistance to standard AMP, particularly in individuals undergoing revision THA. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  2. Auxetic Mechanical Metamaterials to Enhance Sensitivity of Stretchable Strain Sensors.

    Jiang, Ying; Liu, Zhiyuan; Matsuhisa, Naoji; Qi, Dianpeng; Leow, Wan Ru; Yang, Hui; Yu, Jiancan; Chen, Geng; Liu, Yaqing; Wan, Changjin; Liu, Zhuangjian; Chen, Xiaodong

    2018-03-01

    Stretchable strain sensors play a pivotal role in wearable devices, soft robotics, and Internet-of-Things, yet these viable applications, which require subtle strain detection under various strain, are often limited by low sensitivity. This inadequate sensitivity stems from the Poisson effect in conventional strain sensors, where stretched elastomer substrates expand in the longitudinal direction but compress transversely. In stretchable strain sensors, expansion separates the active materials and contributes to the sensitivity, while Poisson compression squeezes active materials together, and thus intrinsically limits the sensitivity. Alternatively, auxetic mechanical metamaterials undergo 2D expansion in both directions, due to their negative structural Poisson's ratio. Herein, it is demonstrated that such auxetic metamaterials can be incorporated into stretchable strain sensors to significantly enhance the sensitivity. Compared to conventional sensors, the sensitivity is greatly elevated with a 24-fold improvement. This sensitivity enhancement is due to the synergistic effect of reduced structural Poisson's ratio and strain concentration. Furthermore, microcracks are elongated as an underlying mechanism, verified by both experiments and numerical simulations. This strategy of employing auxetic metamaterials can be further applied to other stretchable strain sensors with different constituent materials. Moreover, it paves the way for utilizing mechanical metamaterials into a broader library of stretchable electronics. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Internally Mounting Strain Gages

    Jett, J. R., Jr.

    1984-01-01

    Technique for mounting strain gages inside bolt or cylinder simultaneously inserts gage, attached dowel segment, and length of expandable tubing. Expandable tubing holds gage in place while adhesive cures, assuring even distribution of pressure on gage and area gaged.

  4. Running Title: Strained Yoghurts

    USER

    2012-09-27

    Sep 27, 2012 ... ever, the traditional method of producing strained yoghurt ... Food market studies have the essential function of providing ..... Communication No: 2001/21. ... fermented foods and beverages of Turkey. Crit. Rev. Food. Sci. Nutr.

  5. Speech profile of patients undergoing primary palatoplasty.

    Menegueti, Katia Ignacio; Mangilli, Laura Davison; Alonso, Nivaldo; Andrade, Claudia Regina Furquim de

    2017-10-26

    To characterize the profile and speech characteristics of patients undergoing primary palatoplasty in a Brazilian university hospital, considering the time of intervention (early, before two years of age; late, after two years of age). Participants were 97 patients of both genders with cleft palate and/or cleft and lip palate, assigned to the Speech-language Pathology Department, who had been submitted to primary palatoplasty and presented no prior history of speech-language therapy. Patients were divided into two groups: early intervention group (EIG) - 43 patients undergoing primary palatoplasty before 2 years of age and late intervention group (LIG) - 54 patients undergoing primary palatoplasty after 2 years of age. All patients underwent speech-language pathology assessment. The following parameters were assessed: resonance classification, presence of nasal turbulence, presence of weak intraoral air pressure, presence of audible nasal air emission, speech understandability, and compensatory articulation disorder (CAD). At statistical significance level of 5% (p≤0.05), no significant difference was observed between the groups in the following parameters: resonance classification (p=0.067); level of hypernasality (p=0.113), presence of nasal turbulence (p=0.179); presence of weak intraoral air pressure (p=0.152); presence of nasal air emission (p=0.369), and speech understandability (p=0.113). The groups differed with respect to presence of compensatory articulation disorders (p=0.020), with the LIG presenting higher occurrence of altered phonemes. It was possible to assess the general profile and speech characteristics of the study participants. Patients submitted to early primary palatoplasty present better speech profile.

  6. Flexible piezotronic strain sensor.

    Zhou, Jun; Gu, Yudong; Fei, Peng; Mai, Wenjie; Gao, Yifan; Yang, Rusen; Bao, Gang; Wang, Zhong Lin

    2008-09-01

    Strain sensors based on individual ZnO piezoelectric fine-wires (PFWs; nanowires, microwires) have been fabricated by a simple, reliable, and cost-effective technique. The electromechanical sensor device consists of a single electrically connected PFW that is placed on the outer surface of a flexible polystyrene (PS) substrate and bonded at its two ends. The entire device is fully packaged by a polydimethylsiloxane (PDMS) thin layer. The PFW has Schottky contacts at its two ends but with distinctly different barrier heights. The I- V characteristic is highly sensitive to strain mainly due to the change in Schottky barrier height (SBH), which scales linear with strain. The change in SBH is suggested owing to the strain induced band structure change and piezoelectric effect. The experimental data can be well-described by the thermionic emission-diffusion model. A gauge factor of as high as 1250 has been demonstrated, which is 25% higher than the best gauge factor demonstrated for carbon nanotubes. The strain sensor developed here has applications in strain and stress measurements in cell biology, biomedical sciences, MEMS devices, structure monitoring, and more.

  7. Thromboprophylaxis for women undergoing caesarean section.

    Kennedy, C

    2012-02-01

    Thromboprophylaxis for women undergoing caesarean section (CS) was introduced in the hospital in 1995. This study audited the use of tinzaparin prophylaxis in a nested cohort of women who screened negative for diabetes mellitus at 28 weeks gestation. All the women had their weight measured and BMI calculated at the first antenatal visit. Of the 284 women, 68 (24%) had a CS and all received tinzaparin. Of the 68, however, 94% received a dose lower than recommended. Compliance with prophylaxis was complete but compliance with the recommended dosage was suboptimal, which may result in venous thromboembolism after CS despite thromboprophylaxis.

  8. Dermatillomania: In patient undergoing orthodontic treatment

    Adit

    2014-01-01

    Full Text Available Dermatillomania is a disorder in which a person habitually picks their skin, and this is a form of self-injury. It can involve any part of the body, but usually involves the face, neck, arms and shoulders. Symptoms often follow an event that has caused severe emotional distress. A dermatillomania or compulsive skin picking episode may be a conscious response to anxiety or depression but is frequently done as an unconscious habit. In this case report, a patient undergoing orthodontic treatment was found to be suffering from dermatillomania and was treated using psychological counseling.

  9. Care of patients undergoing external radiotherapy

    Lang, C.

    1977-01-01

    The anxiety and associated depression suffered by most patients undergoing radiotherapy is discussed and the possibilities open to the nurse to encourage and reassure patients thus facilitating physical care are considered. The general symptoms of anorexia, nausea, tiredness, skin problems, alopecia, bonemarrow depresssion and rapid tumour destruction are described and nursing care prescribed. The side-effects which may occur following radiation of the brain, head and neck region, eyes, oesophagus, lung, abdomen, pelvis, bones, skin, spine, and spinal cord are considered from the nursing standpoint. The specialised subject of radiotherapy in children is discussed briefly. (U.K.)

  10. A new method for measuring creep-strain

    Joas, H.D.

    2001-01-01

    To realise a safe and economic operation of components undergoing creep damage, sometimes a theoretical and an experimental evaluation is necessary. The discussed Creep-Replica-Method is a new possibility to estimate the creep-strain due to the real loading conditions of a component during a certain time of operation which gives a chance to assess the integrity, the consumed life and the possible repairing of a component. (Author)

  11. Strains and Sprains

    ... lot of pressure on a muscle or you push it too far, such as when lifting a heavy object. Strains may be more likely to happen if you haven't warmed up first to get blood circulating to the muscles. They're also common for someone returning to a sport after the off-season. That first time playing ...

  12. Isotope selection for patients undergoing prostate brachytherapy

    Cha, Christine M.; Potters, Louis; Ashley, Richard; Freeman, Katherine; Wang Xiaohong; Waldbaum, Robert; Leibel, Steven

    1999-01-01

    Purpose: Ultrasound-guided trans perineal interstitial permanent prostate brachytherapy (TIPPB) is generally performed with either 103 Pd or 125 I. The use of 125 I for low Gleason score tumors and 103 Pd for higher Gleason scores has been suggested based on isotope dose rate and cell doubling time observed in in vitro studies. While many centers follow these isotope selection criteria, other centers have elected to use only a single isotope, regardless of Gleason score. No clinical data have been published comparing these isotopes. This study was undertaken to compare outcomes between 125 I and 103 Pd in a matched pair analysis for patients undergoing prostate brachytherapy. Methods and Materials: Six hundred forty-eight consecutively treated patients with clinically confined prostate cancer underwent TIPPB between June 1992 and February 1997. Five hundred thirty-two patients underwent TIPPB alone, whereas 116 received pelvic external beam irradiation and TIPPB. Ninety-three patients received androgen deprivation therapy prior to TIPPB. The prescribed doses for TIPPB were 160 Gy for 125 I (pre-TG43) and 120 Gy for 103 Pd. Patients treated with combination therapy received 41.4 or 45 Gy (1.8 Gy/fraction) external beam irradiation followed by a 3- to 5-week break and then received either a 120-Gy 125 I or a 90-Gy 103 Pd implant. Until November 1994, all patients underwent an 125 I implant after which the isotope selection was based on either Gleason score (Gleason score 2-5: 125 I; Gleason 5-8: 103 Pd) or isotope availability. A matched pair analysis was performed to assess any difference between isotopes. Two hundred twenty-two patients were matched according to Gleason score, prostate-specific antigen (PSA), and stage. PSA relapse-free survival (PSA-RFS) was calculated based on the American Society for Therapeutic Radiology and Oncology (ASTRO) Consensus Group definition of failure. Kaplan-Meier actuarial survival curves were compared to assess differences in

  13. Global Strain in Severe Aortic Valve Stenosis

    Dahl, Jordi S; Videbæk, Lars; Poulsen, Mikael K

    2012-01-01

    Score, history with ischemic heart disease and ejection fraction. CONCLUSIONS: -In patients with symptomatic severe aortic stenosis undergoing AVR reduced GLS provides important prognostic information beyond standard risk factors. Clinical Trial Registration-URL: http://www.clinicaltrial.gov. Unique identifier......BACKGROUND: -Global longitudinal systolic strain (GLS) is often reduced in aortic stenosis despite normal ejection fraction. The importance of reduced preoperative GLS on long-term outcome after aortic valve replacement (AVR) is unknown. METHODS AND RESULTS: -A total of 125 patients with severe...... and mortality. In a stepwise cox model with forward selection GLS was the sole independent predictor HR=1.13 (95% confidence interval 1.02-1.25), p=0.04. Comparing the overall log likelihood χ(2) of the predictive power of the multivariable model containing GLS was statistically superior to models based on Euro...

  14. Plasma fibronectin in patients undergoing major surgery

    Sallam, M.H.M.

    2003-01-01

    Plasma fibronectin in patients undergoing major surgery had been determined before and after operation. The study was done on 15 patients and 15 normal healthy individuals. The study revealed that patients subjected to major operation, their fibronectin level was normal before operation followed by reduction one day post-operation. After one week, fibronectin level raised again nearly to the pre-operations levels. The probable mechanisms of fibronectin in healing processes were discussed. Fibronectin (FN) is a family of structurally and immunologically related high molecular weight glycoproteins that are present in many cell surfaces, in extracellular fluids, in connective tissues and in most membranes. Interaction with certain discrete extracellular substances, such as a glucosaminoglycans (e.g. heparin), fibrin and collagen and with cell surface structure seem to account for many of its biological activities, among which are regulation of adhesion, spreading and locomotion (Mosesson and amrani, 1980). The concentration of Fn in human plasma decreases after extensive destruction such as that occurs in major surgery, burns or other trauma. This decrease has been generally though to be due to increased consumption of soluble plasma Fn in opsonization of particulate and soluble debris from circulation by the reticuloendothelial (RE) system. Fn rapidly appears in injury areas, in experimentally induced blisters, wounded and epithelium tissues (Petersen et al., 1985). Fn accumulates at times of increased vascular permeability and it is produced by cell of blood vessels in response to injury

  15. Helicobacter pylori infection in patients undergoing appendectomy.

    Pavlidis, T E; Atmatzidis, K S; Papaziogas, B T; Souparis, A; Koutelidakis, I M; Papaziogas, T B

    2002-01-01

    Helicobacter pylori has been found in the upper gastrointestinal tract; it is incriminated as aetiological factor in various pathological conditions. This prospective study assesses the presence of this microorganism in the appendix flora and the possible role of its infection in the pathogenesis of acute appendicitis. H. pylori was investigated in 46 consecutive patients undergoing emergent appendectomy for presumed acute appendicitis. Blood sample for serological test of H. pylori infection was drawn before operation. The removed appendix specimen was stained for H. pylori; confirmation was made by PCR (Polymerase Chain Reaction) analysis. The intensity of inflammation was determined pathologically grading from no inflammation to gangrenous appendicitis. Statistical analysis was made using the chi-square test. Seropositivity for H. pylori infection was found in 18 patients (39%), but the microbe was detected in just two appendix specimens (4%). In all seropositive patients acute appendicitis was confirmed by the pathology study; serous (33%) and purulent or gangrenous (67%). The latter incidence in the seronegative patients was 50%. There were found eight specimens (17%) negative for inflammation dealing all with seronegative patients. It seems that H. pylori colonizes the appendix in small proportion and is unlikely to be associated in direct correlation with acute appendicitis. However, seropositive patients with acute inflammation are likely to suffer from purulent or gangrenous form.

  16. Constipation Risk in Patients Undergoing Abdominal Surgery

    Celik, Sevim; Atar, Nurdan Yalcin; Ozturk, Nilgun; Mendes, Guler; Kuytak, Figen; Bakar, Esra; Dalgiran, Duygu; Ergin, Sumeyra

    2015-01-01

    Background: Problems regarding bowel elimination are quite common in patients undergoing abdominal surgery. Objectives: To determine constipation risk before the surgery, bowel elimination during postoperative period, and the factors affecting bowel elimination. Patients and Methods: This is a cross-sectional study. It was conducted in a general surgery ward of a university hospital in Zonguldak, Turkey between January 2013 and May 2013. A total of 107 patients were included in the study, who were selected by convenience sampling. Constipation Risk Assessment Scale (CRAS), patient information form, medical and nursing records were used in the study. Results: The mean age of the patients was found to be 55.97 ± 15.74 (year). Most of the patients have undergone colon (37.4%) and stomach surgeries (21.5%). Open surgical intervention (83.2%) was performed on almost all patients (96.3%) under general anesthesia. Patients were at moderate risk for constipation with average scores of 11.71 before the surgery. A total of 77 patients (72%) did not have bowel elimination problem during postoperative period. The type of the surgery (P < 0.05), starting time for oral feeding after the surgery (P < 0.05), and mobilization (P < 0.05) were effective on postoperative bowel elimination. Conclusions: There is a risk for constipation after abdominal surgery. Postoperative practices are effective on the risk of constipation. PMID:26380107

  17. Strains in general relativity

    Bini, Donato; Felice, Fernando de; Geralico, Andrea

    2006-01-01

    The definition of relative accelerations and strains among a set of comoving particles is studied in connection with the geometric properties of the frame adapted to a 'fiducial observer'. We find that a relativistically complete and correct definition of strains must take into account the transport law of the chosen spatial triad along the observer's congruence. We use special congruences of (accelerated) test particles in some familiar spacetimes to elucidate such a point. The celebrated idea of Szekeres' compass of inertia, arising when studying geodesic deviation among a set of free-falling particles, is here generalized to the case of accelerated particles. In doing so we have naturally contributed to the theory of relativistic gravity gradiometer. Moreover, our analysis was made in an observer-dependent form, a fact that would be very useful when thinking about general relativistic tests on space stations orbiting compact objects like black holes and also in other interesting gravitational situations

  18. Strain Induced Adatom Correlations

    Kappus, Wolfgang

    2012-01-01

    A Born-Green-Yvon type model for adatom density correlations is combined with a model for adatom interactions mediated by the strain in elastic anisotropic substrates. The resulting nonlinear integral equation is solved numerically for coverages from zero to a limit given by stability constraints. W, Nb, Ta and Au surfaces are taken as examples to show the effects of different elastic anisotropy regions. Results of the calculation are shown by appropriate plots and discussed. A mapping to sup...

  19. Ratchetting strain prediction

    Noban, Mohammad; Jahed, Hamid

    2007-01-01

    A time-efficient method for predicting ratchetting strain is proposed. The ratchetting strain at any cycle is determined by finding the ratchetting rate at only a few cycles. This determination is done by first defining the trajectory of the origin of stress in the deviatoric stress space and then incorporating this moving origin into a cyclic plasticity model. It is shown that at the beginning of the loading, the starting point of this trajectory coincides with the initial stress origin and approaches the mean stress, displaying a power-law relationship with the number of loading cycles. The method of obtaining this trajectory from a standard uniaxial asymmetric cyclic loading is presented. Ratchetting rates are calculated with the help of this trajectory and through the use of a constitutive cyclic plasticity model which incorporates deviatoric stresses and back stresses that are measured with respect to this moving frame. The proposed model is used to predict the ratchetting strain of two types of steels under single- and multi-step loadings. Results obtained agree well with the available experimental measurements

  20. Strain measurement based battery testing

    Xu, Jeff Qiang; Steiber, Joe; Wall, Craig M.; Smith, Robert; Ng, Cheuk

    2017-05-23

    A method and system for strain-based estimation of the state of health of a battery, from an initial state to an aged state, is provided. A strain gauge is applied to the battery. A first strain measurement is performed on the battery, using the strain gauge, at a selected charge capacity of the battery and at the initial state of the battery. A second strain measurement is performed on the battery, using the strain gauge, at the selected charge capacity of the battery and at the aged state of the battery. The capacity degradation of the battery is estimated as the difference between the first and second strain measurements divided by the first strain measurement.

  1. Adapting immunisation schedules for children undergoing chemotherapy.

    Fernández-Prada, María; Rodríguez-Martínez, María; García-García, Rebeca; García-Corte, María Dolores; Martínez-Ortega, Carmen

    2018-02-01

    Children undergoing chemotherapy for cancer have special vaccination needs after completion of the treatment. The aim of this study was to evaluate the adaptation of post-chemotherapy vaccination schedules. An observational study was performed on a retrospective cohort that included all children aged from 0 to 14 years, who completed chemotherapy in a tertiary hospital between 2009 and 2015. Inclusion and exclusion criteria were applied. Immunisation was administered in accordance with the guidelines of the Vaccine Advisory Committee of the Spanish Association of Paediatrics. Primary Care immunisation and clinical records of the Preventive Medicine and Public Health Department were reviewed. Of the 99 children who had received chemotherapy, 51 (70.6% males) were included in the study. As regards the type of tumour, 54.9% had a solid organ tumour, and 45.1% had a haematological tumour. Post-chemotherapy immunisation was administered to 70.6%. The most common vaccines received were: diphtheria-tetanus-pertussis or diphtheria-tetanus (54.9%), meningococcus C (41.2%), and seasonal influenza (39.2%). The rate of adaptation of the immunisation schedule after chemotherapy was 9.8%. The pneumococcal conjugate vaccine against 7v or 13v was administered to 21.6% of study subjects. However, only 17.6% received polysaccharide 23v. None received vaccination against hepatitis A. No statistically significant differences were observed between adherence to immunisation schedules and type of tumour (P=.066), gender (P=.304), or age (P=.342). Post-chemotherapy immunisation of children with cancer is poor. The participation of health professionals in training programs and referral of paediatric cancer patients to Vaccine Units could improve the rate of schedule adaptation and proper immunisation of this population. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  2. Preoperative information needs of children undergoing tonsillectomy.

    Buckley, Aoife

    2012-02-01

    AIMS AND OBJECTIVES: To identify the information needs of children undergoing tonsillectomy with reference to content of information, method of delivery, information providers and timing of information provision. BACKGROUND: Tonsillectomy can be anxiety provoking for children and preoperative preparation programmes are long recognised to reduce anxiety. However, few have been designed from the perspectives of children and to date little is known about how best to prepare children in terms of what to tell them, how to convey information to them, who can best provide information and what is the best timing for information provision. DESIGN: A qualitative descriptive study. METHOD: Data were collected from nine children (aged 6-9) using interviews supported by a write and draw technique. Data were coded and categorised into themes reflecting content, method, providers and timing of information. RESULTS: Children openly communicated their information needs especially on what to tell them to expect when facing a tonsillectomy. Their principal concerns were about operation procedures, experiencing \\'soreness\\' and discomfort postoperatively and parental presence. Mothers were viewed as best situated to provide them with information. Children were uncertain about what method of information and timing would be most helpful to them. CONCLUSION: Preoperative educational interventions need to take account of children\\'s information needs so that they are prepared for surgery in ways that are meaningful and relevant to them. Future research is needed in this area. RELEVANCE TO CLINICAL PRACTICE: Practical steps towards informing children about having a tonsillectomy include asking them what they need to know and addressing their queries accordingly. Child-centred information leaflets using a question and answer format could also be helpful to children.

  3. Studies on Drosophila radiosensitive strains

    Varentsova, E.P.; Zakharov, I.A.

    1976-01-01

    45 of radiosensitive strains of Drosophila melanogaster were isolated by Curly/Lobe technique after EMS treatment of Livadia population males. The lethality of non-Curly late larvae after gamma-irradiation (4000r) characterized radiosensitivity strains. Most of them exhibited higher frequency of the spontaneous dominant lethals (up to 69%). The males of 6 strains were semi-sterile. 5 of these strains exhibited higher frequency of X-chromosome non-disjunction

  4. Strain induced adatom correlations

    Kappus, Wolfgang

    2012-12-01

    A Born-Green-Yvon type model for adatom density correlations is combined with a model for adatom interactions mediated by the strain in elastic anisotropic substrates. The resulting nonlinear integral equation is solved numerically for coverages from zero to a limit given by stability constraints. W, Nb, Ta and Au surfaces are taken as examples to show the effects of different elastic anisotropy regions. Results of the calculation are shown by appropriate plots and discussed. A mapping to superstructures is tried. Corresponding adatom configurations from Monte Carlo simulations are shown.

  5. Strain actuated aeroelastic control

    Lazarus, Kenneth B.

    1992-01-01

    Viewgraphs on strain actuated aeroelastic control are presented. Topics covered include: structural and aerodynamic modeling; control law design methodology; system block diagram; adaptive wing test article; bench-top experiments; bench-top disturbance rejection: open and closed loop response; bench-top disturbance rejection: state cost versus control cost; wind tunnel experiments; wind tunnel gust alleviation: open and closed loop response at 60 mph; wind tunnel gust alleviation: state cost versus control cost at 60 mph; wind tunnel command following: open and closed loop error at 60 mph; wind tunnel flutter suppression: open loop flutter speed; and wind tunnel flutter suppression: closed loop state cost curves.

  6. INTESTINAL MALROTATION IN PATIENTS UNDERGOING BARIATRIC SURGERY.

    Vidal, Eduardo Arevalo; Rendon, Francisco Abarca; Zambrano, Trino Andrade; García, Yudoco Andrade; Viteri, Mario Ferrin; Campos, Josemberg Marins; Ramos, Manoela Galvão; Ramos, Almino Cardoso

    Intestinal malrotation is a rare congenital anomaly. In adults is very difficult to recognize due to the lack of symptoms. Diagnosis is usually incidental during surgical procedures or at autopsy. To review the occurrence and recognition of uneventful intestinal malrotation discovered during regular cases of bariatric surgeries. Were retrospectively reviewed the medical registry of 20,000 cases undergoing bariatric surgery, from January 2002 to January 2016, looking for the occurrence of intestinal malrotation and consequences in the intraoperative technique and immediate evolution of the patients. Five cases (0,025%) of intestinal malrotation were found. All of them were males, aging 45, 49, 37,52 and 39 years; BMI 35, 42, 49, 47 and 52 kg/m2, all of them with a past medical history of morbid obesity. The patient with BMI 35 kg/m2 suffered from type 2 diabetes also. All procedures were completed by laparoscopic approach, with no conversions. In one patient was not possible to move the jejunum to the upper abdomen in order to establish the gastrojejunostomy and a sleeve gastrectomy was performed. In another patient was not possible to fully recognize the anatomy due to bowel adhesions and a single anastomosis gastric bypass was preferred. No leaks or bleeding were identified. There were no perioperative complications. All patients were discharged 72 h after the procedure and no immediate 30-day complications were reported. Patients with malrotation can successfully undergo laparoscopic bariatric surgery. May be necessary changes in the surgical original strategy regarding the malrotation. Surgeons must check full abdominal anatomical condition prior to start the division of the stomach. Má-rotação intestinal é rara anomalia congênita em adultos de difícil reconhecimento devido à falta de sintomas. O diagnóstico é feito geralmente incidentalmente durante procedimentos cirúrgicos ou durante autópsia. Verificar a ocorrência e reconhecimento não eventual

  7. Finite-Element Modeling of Viscoelastic Cells During High-Frequency Cyclic Strain

    David W. Holdsworth

    2012-03-01

    Full Text Available Mechanotransduction refers to the mechanisms by which cells sense and respond to local loads and forces. The process of mechanotransduction plays an important role both in maintaining tissue viability and in remodeling to repair damage; moreover, it may be involved in the initiation and progression of diseases such as osteoarthritis and osteoporosis. An understanding of the mechanisms by which cells respond to surrounding tissue matrices or artificial biomaterials is crucial in regenerative medicine and in influencing cellular differentiation. Recent studies have shown that some cells may be most sensitive to low-amplitude, high-frequency (i.e., 1–100 Hz mechanical stimulation. Advances in finite-element modeling have made it possible to simulate high-frequency mechanical loading of cells. We have developed a viscoelastic finite-element model of an osteoblastic cell (including cytoskeletal actin stress fibers, attached to an elastomeric membrane undergoing cyclic isotropic radial strain with a peak value of 1,000 µstrain. The results indicate that cells experience significant stress and strain amplification when undergoing high-frequency strain, with peak values of cytoplasmic strain five times higher at 45 Hz than at 1 Hz, and peak Von Mises stress in the nucleus increased by a factor of two. Focal stress and strain amplification in cells undergoing high-frequency mechanical stimulation may play an important role in mechanotransduction.

  8. Colony Dimorphism in Bradyrhizobium Strains

    Sylvester-Bradley, Rosemary; Thornton, Philip; Jones, Peter

    1988-01-01

    Ten isolates of Bradyrhizobium spp. which form two colony types were studied; the isolates originated from a range of legume species. The two colony types differed in the amount of gum formed or size or both, depending on the strain. Whole 7-day-old colonies of each type were subcultured to determine the proportion of cells which had changed to the other type. An iterative computerized procedure was used to determine the rate of switching per generation between the two types and to predict proportions reached at equilibrium for each strain. The predicted proportions of the wetter (more gummy) or larger colony type at equilibrium differed significantly between strains, ranging from 0.9999 (strain CIAT 2383) to 0.0216 (strain CIAT 2469), because some strains switched faster from dry to wet (or small to large) and others switched faster from wet to dry (or large to small). Predicted equilibrium was reached after about 140 generations in strain USDA 76. In all but one strain (CIAT 3030) the growth rate of the wetter colony type was greater than or similar to that of the drier type. The mean difference in generation time between the two colony types was 0.37 h. Doubling times calculated for either colony type after 7 days of growth on the agar surface ranged from 6.0 to 7.3 h. The formation of two persistent colony types by one strain (clonal or colony dimorphism) may be a common phenomenon among Bradyrhizobium strains. Images PMID:16347599

  9. Longitudinal strain predicts left ventricular mass regression after aortic valve replacement for severe aortic stenosis and preserved left ventricular function.

    Gelsomino, Sandro; Lucà, Fabiana; Parise, Orlando; Lorusso, Roberto; Rao, Carmelo Massimiliano; Vizzardi, Enrico; Gensini, Gian Franco; Maessen, Jos G

    2013-11-01

    We explored the influence of global longitudinal strain (GLS) measured with two-dimensional speckle-tracking echocardiography on left ventricular mass regression (LVMR) in patients with pure aortic stenosis (AS) and normal left ventricular function undergoing aortic valve replacement (AVR). The study population included 83 patients with severe AS (aortic valve area regression (all P regression in patients with pure AS undergoing AVR. Our findings must be confirmed by further larger studies.

  10. Strain Pattern in Supercooled Liquids

    Illing, Bernd; Fritschi, Sebastian; Hajnal, David; Klix, Christian; Keim, Peter; Fuchs, Matthias

    2016-11-01

    Investigations of strain correlations at the glass transition reveal unexpected phenomena. The shear strain fluctuations show an Eshelby-strain pattern [˜cos (4 θ ) /r2 ], characteristic of elastic response, even in liquids, at long times. We address this using a mode-coupling theory for the strain fluctuations in supercooled liquids and data from both video microscopy of a two-dimensional colloidal glass former and simulations of Brownian hard disks. We show that the long-ranged and long-lived strain signatures follow a scaling law valid close to the glass transition. For large enough viscosities, the Eshelby-strain pattern is visible even on time scales longer than the structural relaxation time τ and after the shear modulus has relaxed to zero.

  11. Hydrogen production from microbial strains

    Harwood, Caroline S; Rey, Federico E

    2012-09-18

    The present invention is directed to a method of screening microbe strains capable of generating hydrogen. This method involves inoculating one or more microbes in a sample containing cell culture medium to form an inoculated culture medium. The inoculated culture medium is then incubated under hydrogen producing conditions. Once incubating causes the inoculated culture medium to produce hydrogen, microbes in the culture medium are identified as candidate microbe strains capable of generating hydrogen. Methods of producing hydrogen using one or more of the microbial strains identified as well as the hydrogen producing strains themselves are also disclosed.

  12. Asymptomatic bacteriuria Escherichia coli strains

    Hancock, Viktoria; Nielsen, E.M.; Klemm, Per

    2006-01-01

    Urinary tract infections (UTIs) affect millions of people each year. Escherichia coli is the most common organism associated with asymptomatic bacteriuria (ABU) in humans. Persons affected by ABU may carry a particular E. coli strain for extended periods of time without any symptoms. In contrast...... to uropathogenic E. coli (UPEC) that cause symptomatic UTI, very little is known about the mechanisms by which these strains colonize the urinary tract. Here, we have investigated the growth characteristics in human urine as well as adhesin repertoire of nine ABU strains; the ability of ABU strains to compete...

  13. Coagulation profile in patients undergoing video-assisted thoracoscopic lobectomy

    Christensen, Thomas Decker; Vad, Henrik; Pedersen, Søren

    2017-01-01

    -, and the first two days postoperatively by standard coagulation blood test, thromboelastometry (ROTEM®) and thrombin generation. Results: Patients undergoing potential curative surgery for lung cancer were not hypercoagulable preoperatively. There was no statistically significant difference in the majority......Background: Knowledge about the impact of Low-Molecular-Weight Heparin (LMWH) on the coagulation system in patients undergoing minimal invasive lung cancer surgery is sparse. The aim of this study was to assess the effect of LMWH on the coagulation system in patients undergoing Video......-Assisted Thoracoscopic Surgery (VATS) lobectomy for primary lung cancer. Methods: Sixty-three patients diagnosed with primary lung cancer undergoing VATS lobectomy were randomized to either subcutaneous injection with dalteparin (Fragmin®) 5000 IE once daily or no intervention. Coagulation was assessed pre-, peri...

  14. Experiense with remineraling means in patients undergoing orthodontic treatment

    Stepanova Ye.A.

    2011-03-01

    Full Text Available In patients undergoing orthodontic treatment using bracket-technology a high risk of caries development. The algorithm of preventive interventions for the prevention of hair demineralization of enamel of the teeth

  15. Preoperative B-type natriuretic peptides in patients undergoing ...

    Southern African Journal of Anaesthesia and Analgesia ... Preoperative B-type natriuretic peptides in patients undergoing noncardiac surgery: a cumulative ... Future investigation should focus on the clinical implications of these data and the ...

  16. Do patients fear undergoing general anesthesia for oral surgery?

    Elmore, Jasmine R; Priest, James H; Laskin, Daniel M

    2014-01-01

    Many patients undergoing major surgery have more fear of the general anesthesia than the procedure. This appears to be reversed with oral surgery. Therefore, patients need to be as well informed about this aspect as the surgical operation.

  17. Preoperative autologous plateletpheresis in patients undergoing open heart surgery.

    Tomar Akhlesh; Tempe Deepak; Banerjee A; Hegde R; Cooper A; Khanna S

    2003-01-01

    Blood conservation is an important aspect of care provided to the patients undergoing cardiac operations with cardiopulmonary bypass (CPB). It is even more important in patients with anticipated prolonged CPB, redo cardiac surgery, patients having negative blood group and in patients undergoing emergency cardiac surgery. In prolonged CPB the blood is subjected to more destruction of important coagulation factors, in redo surgery the separation of adhesions leads to increased bleeding and diff...

  18. Molecular relationships between closely related strains and species of nematodes

    Butler, M. H.; Wall, S. M.; Luehrsen, K. R.; Fox, G. E.; Hecht, R. M.

    1981-01-01

    Electrophoretic comparisons have been made for 24 enzymes in the Bergerac and Bristol strains of Caenorhabditis elegans and the related species, Caenorhabditis briggsae. No variation was detected between the two strains of C. elegans. In contrast, the two species, C. elegans and C. briggsae exhibited electrophoretic differences in 22 of 24 enzymes. A consensus 5S rRNA sequence was determined for C. elegans and found to be identical to that from C. briggsae. By analogy with other species with relatively well established fossil records it can be inferred that the time of divergence between the two nematode species is probably in the tens of millions of years. The limited anatomical evolution during a time period in which proteins undergo extensive changes supports the hypothesis that anatomical evolution is not dependent on overall protein changes.

  19. TL transgenic mouse strains

    Obata, Y.; Matsudaira, Y.; Hasegawa, H.; Tamaki, H.; Takahashi, T.; Morita, A.; Kasai, K.

    1993-01-01

    As a result of abnormal development of the thymus of these mice, TCR αβ lineage of the T cell differentiation is disturbed and cells belonging to the TCR γδ CD4 - CD8 - double negative (DN) lineage become preponderant. The γδ DN cells migrate into peripheral lymphoid organs and constitute nearly 50% of peripheral T cells. Immune function of the transgenic mice is severely impaired, indicating that the γδ cells are incapable of participating in these reactions. Molecular and serological analyses of T-cell lymphomas reveal that they belong to the γδ lineage. Tg.Tla a -3-1 mice should be useful in defining the role of TL in normal and abnormal T cell differentiation as well as in the development of T-cell lymphomas, and further they should facilitate studies on the differentiation and function of γδ T cells. We isolated T3 b -TL gene from B6 mice and constructed a chimeric gene in which T3 b -TL is driven by the promoter of H-2K b . With the chimeric gene, two transgenic mouse strains, Tg. Con.3-1 and -2 have been derived in C3H background. Both strains express TL antigen in various tissues including skin. The skin graft of transgenic mice on C3H and (B6 X C3H)F 1 mice were rejected. In the mice which rejected the grafts, CD8 + TCRαβ cytotoxic T cells (CTL) against TL antigens were recognized. The recognition of TL by CTL did not require the antigen presentation by H-2 molecules. The results indicated that TL antigen in the skin becomes a transplantation antigen and behaves like a typical allogeneic MHC class I antigen. The facts that (B6 X C3H)F 1 mice rejected the skin expressing T3 b -TL antigen and induced CTL that killed TL + lymphomas of B6 origin revealed that TL antigen encoded by T3 b -TL is recognized as non-self in B6 mice. Experiments are now extended to analyze immune responses to TL antigen expressed on autochthonous T cell lymphomas. (J.P.N.)

  20. Nutritionally fastidious Ruminococct $ flovefociens : strains

    than those obtained in a medium containing rumen fluid. Growth of all strains was remarkably uniform. Where the same inoculum was used, differences in the qualitative com- position of the medium usually had little effect on growth. In contrast, the R. f/avefaciens strains were much more variable in their growth responses.

  1. Haldane model under nonuniform strain

    Ho, Yen-Hung; Castro, Eduardo V.; Cazalilla, Miguel A.

    2017-10-01

    We study the Haldane model under strain using a tight-binding approach, and compare the obtained results with the continuum-limit approximation. As in graphene, nonuniform strain leads to a time-reversal preserving pseudomagnetic field that induces (pseudo-)Landau levels. Unlike a real magnetic field, strain lifts the degeneracy of the zeroth pseudo-Landau levels at different valleys. Moreover, for the zigzag edge under uniaxial strain, strain removes the degeneracy within the pseudo-Landau levels by inducing a tilt in their energy dispersion. The latter arises from next-to-leading order corrections to the continuum-limit Hamiltonian, which are absent for a real magnetic field. We show that, for the lowest pseudo-Landau levels in the Haldane model, the dominant contribution to the tilt is different from graphene. In addition, although strain does not strongly modify the dispersion of the edge states, their interplay with the pseudo-Landau levels is different for the armchair and zigzag ribbons. Finally, we study the effect of strain in the band structure of the Haldane model at the critical point of the topological transition, thus shedding light on the interplay between nontrivial topology and strain in quantum anomalous Hall systems.

  2. People's experiences of suffering a lower limb fracture and undergoing surgery.

    Forsberg, Angelica; Söderberg, Siv; Engström, Åsa

    2014-01-01

    To describe people's experiences of suffering a lower limb fracture and undergoing surgery, from the time of injury through to the care given at the hospital and recovery following discharge. There is a lack of research on people's experiences of suffering a lower limb fracture and undergoing surgery - from injury to recovery. A qualitative approach was used. Interviews with nine participants were subjected to thematic content analysis. One theme was expressed: from realising the seriousness of the injury to regaining autonomy. Participants described feelings of frustration and helplessness when realising the seriousness of their injury. The wait prior to surgery was a strain and painful experience, and participants needed orientation for the future. They expressed feelings of vulnerability about being in the hands of staff during surgery. After surgery, in the postanaesthesia unit, participants expressed a need to have control and to feel safe in their new situation. To mobilise and regain their autonomy was a struggle, and participants stated that their recovery was extended. Participants found themselves in a new and unexpected situation and experienced pain, vulnerability and a striving for control during the process, that is, 'from realising the seriousness of the injury to regaining autonomy'. How this is managed depends on how the patient's needs are met by nurses. The nursing care received while suffering a lower limb fracture and undergoing surgery should be situation specific as well as individual specific. The safe performance of technical interventions and the nurse's comprehensive explanations of medical terms may help the patient to feel secure during the process. © 2013 John Wiley & Sons Ltd.

  3. Pin clad strains in Phenix

    Languille, A.

    1979-07-01

    The Phenix reactor has operated for 4 years in a satisfactory manner. The first 2 sub-assembly loadings contained pins clad in solution treated 316. The principal pin strains are: diametral strain (swelling and irradiation creep), ovality and spiral bending of the pin (interaction of wire and pin cluster and wrapper). A pin cluster irradiated to a dose of 80 dpa F reached a pin diameter strain of 5%. This strain is principally due to swelling (low fission gas pressure). The principal parameters governing the swelling are instantaneous dose, time and temperature for a given type of pin cladding. Other types of steel are or will be irradiated in Phenix. In particular, cold-worked titanium stabilised 316 steel should contribute towards a reduction in the pin clad strains and increase the target burn-up in this reactor. (author)

  4. Strain expansion-reduction approach

    Baqersad, Javad; Bharadwaj, Kedar

    2018-02-01

    Validating numerical models are one of the main aspects of engineering design. However, correlating million degrees of freedom of numerical models to the few degrees of freedom of test models is challenging. Reduction/expansion approaches have been traditionally used to match these degrees of freedom. However, the conventional reduction/expansion approaches are only limited to displacement, velocity or acceleration data. While in many cases only strain data are accessible (e.g. when a structure is monitored using strain-gages), the conventional approaches are not capable of expanding strain data. To bridge this gap, the current paper outlines a reduction/expansion technique to reduce/expand strain data. In the proposed approach, strain mode shapes of a structure are extracted using the finite element method or the digital image correlation technique. The strain mode shapes are used to generate a transformation matrix that can expand the limited set of measurement data. The proposed approach can be used to correlate experimental and analytical strain data. Furthermore, the proposed technique can be used to expand real-time operating data for structural health monitoring (SHM). In order to verify the accuracy of the approach, the proposed technique was used to expand the limited set of real-time operating data in a numerical model of a cantilever beam subjected to various types of excitations. The proposed technique was also applied to expand real-time operating data measured using a few strain gages mounted to an aluminum beam. It was shown that the proposed approach can effectively expand the strain data at limited locations to accurately predict the strain at locations where no sensors were placed.

  5. Assessing Cardiovascular Health Using Life′s Simple 7 in a Chinese Population Undergoing Stroke Prevention

    Qiong Yang

    2015-01-01

    Conclusions: Few Chinese patients undergoing stroke prevention had optimal CVH (determined using LS7. Additionally, fewer patients undergoing secondary prevention had optimal CVH than those undergoing primary prevention. In particular, physical activity and diet status in this population require improvement.

  6. Roll bonding of strained aluminium

    Staun, Jakob M.

    2003-01-01

    This report investigates roll bonding of pre-strained (å ~ 4) aluminium sheets to produce high strain material from high purity aluminium (99.996%) and commercial pure aluminium (99.6%). The degree of bonding is investigated by optical microscopy and ultrasonic scanning. Under the right...... of the cross rolled volume fraction is found. To further asses this effect, and the anisotropy, it is necessary to acquire knowledge about both texture and microstructure, e.g. by TEM. Roll bonding of pre-strained aluminium is found to be a possible alternative to ARB in the quest for ultra-fine grained...

  7. Strain fluctuations and elastic constants

    Parrinello, M.; Rahman, A.

    1982-03-01

    It is shown that the elastic strain fluctuations are a direct measure of elastic compliances in a general anisotropic medium; depending on the ensemble in which the fluctuation is measured either the isothermal or the adiabatic compliances are obtained. These fluctuations can now be calculated in a constant enthalpy and pressure, and hence, constant entropy, ensemble due to recent develpments in the molecular dynamics techniques. A calculation for a Ni single crystal under uniform uniaxial 100 tensile or compressive load is presented as an illustration of the relationships derived between various strain fluctuations and the elastic modulii. The Born stability criteria and the behavior of strain fluctuations are shown to be related.

  8. Strain accumulation in quasicrystalline solids

    Nori, F.; Ronchetti, M.; Elser, V.

    1988-01-01

    We study the relaxation of 2D quasicrystalline elastic networks when their constituent bonds are perturbed homogeneously. Whereas ideal, quasiperiodic networks are stable against such perturbations, we find significant accumulations of strain in a class of disordered networks generated by a growth process. The grown networks are characterized by root mean square phason fluctuations which grow linearly with system size. The strain accumulation we observe in these networks also grows linearly with system size. Finally, we find a dependence of strain accumulation on cooling rate

  9. Selection of autochthonous Oenococcus oeni strains according to their oenological properties and vinification results.

    Ruiz, Patricia; Izquierdo, Pedro Miguel; Seseña, Susana; Palop, María Llanos

    2010-02-28

    The goal of this study is to carry out a characterization of 84 Oenococcus oeni strains isolated from Tempranillo wine samples taken at the cellars in Castilla-La Mancha, in order to select those showing the highest potential as oenological starter cultures. Various oenological properties were analyzed and the ability of some of these strains to grow and undergo MLF in simulated laboratory microvinifications was tested. Twenty-two strains were selected on the basis of fermentation assays and the eight that produced the best results in the chemical analysis of the wines were chosen for further assays. None of the eight strains was either able to produce biogenic amines or displayed tannase or anthocyanase activities. On the other hand all presented activity against p-NP-beta Glucopyranoside, p-NP-alpha Glucopyranoside and p-NP-beta xylopyranoside. Randomly Amplified Polymorphic DNA (RAPD)-PCR was used to determine the colonizing ability of the inoculated strains. C22L9 and D13L13 strains showed the highest implantation values. On the basis of this characterization, two strains have been selected which are suitable as starter cultures for MLF of Tempranillo wine. Use of these strains will ensure that MLF proceeds successfully and gives retention of the organoleptic characteristics of wines made in Castilla-La Mancha. (c) 2009 Elsevier B.V. All rights reserved.

  10. Strain-dependent magnetic anisotropy in GaMnAs on InGaAs templates

    Daeubler, Joachim; Glunk, Michael; Schwaiger, Stephan; Dreher, Lukas; Schoch, Wladimir; Sauer, Rolf; Limmer, Wolfgang [Institut fuer Halbleiterphysik, Universitaet Ulm, 89069 Ulm (Germany)

    2008-07-01

    We have systematically studied the influence of strain on the magnetic anisotropy of GaMnAs by means of HRXRD reciprocal space mapping and angle-dependent magnetotransport. For this purpose, a series of GaMnAs layers with Mn contents of {proportional_to}5% was grown by low-temperature MBE on relaxed InGaAs/GaAs templates with different In concentrations, enabling us to vary the strain in the GaMnAs layers continuously from tensile to compressive, including the unstrained state. Considering both, as-grown and annealed samples, the anisotropy parameter describing the uniaxial out-of-plane magnetic anisotropy has been found to vary linearly with hole density and strain. As a consequence, the out-of-plane direction gradually undergoes a transition from a magnetic hard axis to a magnetic easy axis from compressive to tensile strain.

  11. Strain localisation in granular media

    Desrues , Jacques

    1984-01-01

    This study is devoted to strain localisation in Granular materials. Both experimental and theoretical results have been obtained.The first part of the thesis is a review of the methods and theories about rupture in sols mechanics and more generally, in solid mechanics. The classical framework of Shear Band analysis is presented, and the main results available for different classes of materials are discussed.The second part describes an experimental study of strain localisation in sand specime...

  12. Geographic variation in sexual attraction of Spodoptera frugiperda corn- and rice-strain males to pheromone lures

    Unbehend, M.; Hänniger, S.; Vásquez, G.M.; Juárez, M.L.; Reisig, D.; McNeil, J.N.; Meagher, R.L.; Jenkins, D.A.; Heckel, D.G.; Groot, A.T.

    2014-01-01

    The corn- and rice-strains of Spodoptera frugiperda exhibit several genetic and behavioral differences and appear to be undergoing ecological speciation in sympatry. Previous studies reported conflicting results when investigating male attraction to pheromone lures in different regions, but this

  13. Geographic variation in sexual attraction of Spodoptera frugiperda corn- and rice-strain males to pheromone lures

    The corn- and rice-strains of Spodoptera frugiperda exhibit several genetic and behavioral differences and appear to be undergoing ecological speciation in sympatry. Previous studies reported conflicting results when investigating male attraction to pheromone lures in different regions, but this cou...

  14. Built for speed: strain in the cartilaginous vertebral columns of sharks.

    Porter, M E; Diaz, Candido; Sturm, Joshua J; Grotmol, Sindre; Summers, A P; Long, John H

    2014-02-01

    In most bony fishes vertebral column strain during locomotion is almost exclusively in the intervertebral joints, and when these joints move there is the potential to store and release strain energy. Since cartilaginous fishes have poorly mineralized vertebral centra, we tested whether the vertebral bodies undergo substantial strain and thus may be sites of energy storage during locomotion. We measured axial strains of the intervertebral joints and vertebrae in vivo and ex vivo to characterize the dynamic behavior of the vertebral column. We used sonomicrometry to directly measure in vivo and in situ strains of intervertebral joints and vertebrae of Squalus acanthias swimming in a flume. For ex vivo measurements, we used a materials testing system to dynamically bend segments of vertebral column at frequencies ranging from 0.25 to 1.00 Hz and a range of physiologically relevant curvatures, which were determined using a kinematic analysis. The vertebral centra of S. acanthias undergo strain during in vivo volitional movements as well as in situ passive movements. Moreover, when isolated segments of vertebral column were tested during mechanical bending, we measured the same magnitudes of strain. These data support our hypothesis that vertebral column strain in lateral bending is not limited to the intervertebral joints. In histological sections, we found that the vertebral column of S. acanthias has an intracentral canal that is open and covered with a velum layer. An open intracentral canal may indicate that the centra are acting as tunics around some sections of a hydrostat, effectively stiffening the vertebral column. These data suggest that the entire vertebral column of sharks, both joints and centra, is mechanically engaged as a dynamic spring during locomotion. Copyright © 2013 Elsevier GmbH. All rights reserved.

  15. Deinococcus radiodurans strain R1 contains N6-methyladenine in its genome

    Prasad, Bhaskar Jyoti; Sabnis, Ketaki; Deobagkar, Deepti D.; Deobagkar, Dileep N.

    2005-01-01

    Methylation of DNA is known to be involved in DNA repair mechanisms in bacteria. Deinococcus radiodurans strain R1 on exposure to high radiation undergoes significant DNA damage, which is repaired without mutations. However, the presence of modified nucleotides has not been reported in its genome. We report here the detection of N6-methyladenine in the genome of D. radiodurans strain R1 using immunochemical techniques. This N6-methyladenine is not a part of GATC restriction-modification system. D. radiodurans cell extract also exhibited a DNA adenine methyltransferase activity which was reduced in the early post-irradiation recovery phase

  16. Postoperative atrial fibrillation in patients on statins undergoing ...

    Introduction: The efficacy of perioperative statin therapy in decreasing postoperative morbidity in patients undergoing valve replacements and repairs is unknown. The aim of our study was to determine whether or not the literature supports the hypothesis that statins decrease postoperative atrial fibrillation (AF), and hence ...

  17. 77 FR 6803 - Agency Forms Undergoing Paperwork Reduction Act Review

    2012-02-09

    ... pregnant during Health Questionnaire/ 750 1 20/60 NHANES 1999-2010. Consent Form. 3. State/local vital...-11CE] Agency Forms Undergoing Paperwork Reduction Act Review The Centers for Disease Control and... about the pregnant women at the time of interview. Having information on their children's birth...

  18. 77 FR 37051 - Agency Forms Undergoing Paperwork Reduction Act Review

    2012-06-20

    ... Year 1 and Year 2. Informed Consent Form... 4,404 1 2/60 Non-Responder Interview. 792 1 5/60 Kimberly S...] Agency Forms Undergoing Paperwork Reduction Act Review The Centers for Disease Control and Prevention...-minute interview will be conducted with a 10% sample of non-responders (up to 792 individuals). In order...

  19. 75 FR 68360 - Agency Forms Undergoing Paperwork Reduction Act Review

    2010-11-05

    ...] Agency Forms Undergoing Paperwork Reduction Act Review The Centers for Disease Control and Prevention... screener questionnaire will be used to determine participation eligibility and obtain oral consent. Approximately 7,000 individuals will be approached and screened (through a 2-minute interview) for eligibility...

  20. 75 FR 6671 - Agency Forms Undergoing Paperwork Reduction Act Review

    2010-02-10

    ... programs implemented a new consent form. This form asked participants for permission for CDC to contact...] Agency Forms Undergoing Paperwork Reduction Act Review The Centers for Disease Control and Prevention... prevention behaviors, CDC will conduct telephone interviews of 425 Matter of Balance program participants six...

  1. 75 FR 24706 - Agency Forms Undergoing Paperwork Reduction Act Review

    2010-05-05

    ... parent consent 214 1 10/60 form. Child Clinic Visit--Case 107 1 1.5 children packet. Parent Clinic Visit...] Agency Forms Undergoing Paperwork Reduction Act Review The Centers for Disease Control and Prevention...; (4) a telephone interview focusing on pregnancy-related events and early life history (biological...

  2. 76 FR 38654 - Agency Forms Undergoing Paperwork Reduction Act Review

    2011-07-01

    ... consent for an interview. After the data collection phase, a multidisciplinary case review team (CRT) will... Post-Partum HIV- FIMR/HIV Maternal 300 1 1.5 infected Women. Interview Form. Daniel L. Holcomb, Reports...] Agency Forms Undergoing Paperwork Reduction Act Review The Centers for Disease Control and Prevention...

  3. 77 FR 12594 - Agency Forms Undergoing Paperwork Reduction Act Review

    2012-03-01

    ... Script. Refusal Questions Form.. 62 1 2/60 Individual Consent Form. 250 1 3/60 Contact Information Form... Screening 92 1 5/60 Survey. Informed Consent........ 50 1 1/60 Interview Questionnaire. 50 1 1 Network Size...-12-12BL] Agency Forms Undergoing Paperwork Reduction Act Review The Agency for Toxic Substances and...

  4. 76 FR 55915 - Agency Forms Undergoing Paperwork Reduction Act Review

    2011-09-09

    ... type 2 diabetes DPRP Application Form........ 120 1 1 prevention programs. DPRP Evaluation Data... mechanism for recognizing organizations that deliver effective, community-based type 2 diabetes prevention...] Agency Forms Undergoing Paperwork Reduction Act Review The Centers for Disease Control and Prevention...

  5. Multiple maxillofacial fractures in a patient undergoing orthodontic ...

    A multi-disciplinary team approach for the management of maxillofacial fractures in patients undergoing orthodontic treatment with fixed appliances is suggested. Orthodontic treatment with surgical involvement has been found to improve both facial aesthetics and occlusal function. Key words: Maxillofacial, trauma, ...

  6. Clinical effect of Fuzheng quyu therapy in patients undergoing ...

    Clinical effect of Fuzheng quyu therapy in patients undergoing radiotherapy after cervical carcinoma surgery. ... The clinical effects and the incidence of adverse events were compared between the groups. Results: The plasma prothrombin time and activated partial thromboplastin time improved after treatment in the study ...

  7. Coping strategies used by hospitalized children with cancer undergoing chemotherapy.

    Sposito, Amanda Mota Pacciulio; Silva-Rodrigues, Fernanda Machado; Sparapani, Valéria de Cássia; Pfeifer, Luzia Iara; de Lima, Regina Aparecida Garcia; Nascimento, Lucila Castanheira

    2015-03-01

    To analyze coping strategies used by children with cancer undergoing chemotherapy during hospitalization. This was an exploratory study to analyze qualitative data using an inductive thematic analysis. Semistructured interviews using puppets were conducted with 10 children with cancer, between 7 and 12 years old, who were hospitalized and undergoing chemotherapy. The coping strategies to deal with chemotherapy were: understanding the need for chemotherapy; finding relief for the chemotherapy's side effects and pain; seeking pleasure in nourishment; engaging in entertaining activities and having fun; keeping the hope of cure alive; and finding support in religion. Children with cancer undergoing chemotherapy need to cope with hospitalizations, pain, medication side effects, idle time, and uncertainty regarding the success of treatment. These challenges motivated children to develop their own coping strategies, which were effective while undergoing chemotherapy. By gaining knowledge and further understanding about valid coping strategies during chemotherapy treatment, health professionals can mobilize personal and material resources from the children, health teams, and institutions aiming to potentiate the use of these strategies to make treatments the least traumatic. © 2015 Sigma Theta Tau International.

  8. 75 FR 65489 - Agency Forms Undergoing Paperwork Reduction Act Review

    2010-10-25

    ... children. The three environmental chemicals, Bisphenol A (BPA), phthalates, and mercury have been selected...] Agency Forms Undergoing Paperwork Reduction Act Review The Centers for Disease Control and Prevention (CDC) publishes a list of information collection requests under review by the Office of Management and...

  9. 77 FR 76045 - Agency Forms Undergoing Paperwork Reduction Act Review

    2012-12-26

    ... case classification (disease staging system). Recommendations for revisions in the case definition were... DEPARTMENT OF HEALTH AND HUMAN SERVICES Centers for Disease Control and Prevention [30Day-13-0573] Agency Forms Undergoing Paperwork Reduction Act Review The Centers for Disease Control and Prevention...

  10. post-operative morbidity of the obese patient undergoing posterior

    urinary tract infection, neurological injury and dural tears. Methods: One hundred consecutive patients undergoing ... muscle mass in the human body, in which weight in kilograms is divided by height in meters2). The current .... complications with the exception of one dural tear occurred in the obese patient group. Table 3.

  11. Post-operative morbidity of the obese patient undergoing posterior ...

    Outcome measures: Post-operative morbidity measures – infection, seroma, pulmonary embolism, urinary tract infection, neurological injury and dural tears. Methods: One hundred consecutive patients undergoing posterior lumbar spine surgery were enrolled in the study. Three fellowship trained attending orthopaedic ...

  12. Quality of Life in End Stage Renal Failure Patients Undergoing ...

    We assessed the quality of life of 45 patients with end stage renal failure undergoing dialysis in Mauritius using the standard United Kingdom version of the Short Form 36 Items Health Survey (SF36) questionnaire. Our findings showed that gender, level of social and emotional support, marital status, and travel time were ...

  13. Factors affecting quality of life in cancer patients undergoing ...

    Factors affecting quality of life in cancer patients undergoing chemotherapy. ... Objective: The aim of this study was to evaluate the QoL in cancer patients with solid tumors and at the different chemotherapy cycles (CT). ... Results: A significant relationship between the cancer type, pain intensity, and fatigue was found.

  14. Electroacupuncture for Bladder Function Recovery in Patients Undergoing Spinal Anesthesia

    Gao, Yinqiu; Zhou, Xinyao; Dong, Xichen; Jia, Qing; Xie, Shen; Pang, Ran

    2014-01-01

    Purpose. To determine the efficacy of electroacupuncture on recovering postanesthetic bladder function. Materials and Methods. Sixty-one patients undergoing spinal anaesthesia were recruited and allocated into electroacupuncture or control group randomly. Patients in electroacupuncture group received electroacupuncture therapy whereas ones in control group were not given any intervention. Primary endpoint was incidence of bladder overdistension and postoperative urinary retention. Secondary ...

  15. 77 FR 40363 - Agency Forms Undergoing Paperwork Reduction Act Review

    2012-07-09

    ... Methicillin-resistant Staphylococcus aureus (MRSA) among Patients Recently Discharged from Acute Care... DEPARTMENT OF HEALTH AND HUMAN SERVICES Centers for Disease Control and Prevention [30-Day-12-12II] Agency Forms Undergoing Paperwork Reduction Act Review The Centers for Disease Control and Prevention...

  16. 78 FR 40151 - Agency Forms Undergoing Paperwork Reduction Act Review

    2013-07-03

    ... resistant Staphylococcus aureus ABCs Case Report Form. ABCs Invasive Pneumococcal 10 41 10/60 Disease in... DEPARTMENT OF HEALTH AND HUMAN SERVICES Centers for Disease Control and Prevention [30-Day 13-13DB] Agency Forms Undergoing Paperwork Reduction Act Review The Centers for Disease Control and Prevention...

  17. 75 FR 20601 - Agency Forms Undergoing Paperwork Reduction Act Review

    2010-04-20

    .... Proposed Project Asthma Information Reporting System (AIRS)--New--Air Pollution and Respiratory Health... DEPARTMENT OF HEALTH AND HUMAN SERVICES Centers for Disease Control and Prevention [30Day-10-09CK] Agency Forms Undergoing Paperwork Reduction Act Review The Centers for Disease Control and prevention...

  18. 78 FR 24422 - Agency Forms Undergoing Paperwork Reduction Act Review

    2013-04-25

    ... System (AIRS) (0920-0853, Expiration 06/30/2013)--Extension--Air Pollution and Respiratory Health Branch... DEPARTMENT OF HEALTH AND HUMAN SERVICES Centers for Disease Control and Prevention [30Day-13-0853] Agency Forms Undergoing Paperwork Reduction Act Review The Centers for Disease Control and Prevention...

  19. Clinical feasibility and validation of 3D principal strain analysis from cine MRI: comparison to 2D strain by MRI and 3D speckle tracking echocardiography.

    Satriano, Alessandro; Heydari, Bobak; Narous, Mariam; Exner, Derek V; Mikami, Yoko; Attwood, Monica M; Tyberg, John V; Lydell, Carmen P; Howarth, Andrew G; Fine, Nowell M; White, James A

    2017-12-01

    Two-dimensional (2D) strain analysis is constrained by geometry-dependent reference directions of deformation (i.e. radial, circumferential, and longitudinal) following the assumption of cylindrical chamber architecture. Three-dimensional (3D) principal strain analysis may overcome such limitations by referencing intrinsic (i.e. principal) directions of deformation. This study aimed to demonstrate clinical feasibility of 3D principal strain analysis from routine 2D cine MRI with validation to strain from 2D tagged cine analysis and 3D speckle tracking echocardiography. Thirty-one patients undergoing cardiac MRI were studied. 3D strain was measured from routine, multi-planar 2D cine SSFP images using custom software designed to apply 4D deformation fields to 3D cardiac models to derive principal strain. Comparisons of strain estimates versus those by 2D tagged cine, 2D non-tagged cine (feature tracking), and 3D speckle tracking echocardiography (STE) were performed. Mean age was 51 ± 14 (36% female). Mean LV ejection fraction was 66 ± 10% (range 37-80%). 3D principal strain analysis was feasible in all subjects and showed high inter- and intra-observer reproducibility (ICC range 0.83-0.97 and 0.83-0.98, respectively-p analysis is feasible using routine, multi-planar 2D cine MRI and shows high reproducibility with strong correlations to 2D conventional strain analysis and 3D STE-based analysis. Given its independence from geometry-related directions of deformation this technique may offer unique benefit for the detection and prognostication of myocardial disease, and warrants expanded investigation.

  20. Effect of lattice mismatch-induced strains on coupled diffusive and displacive phase transformations

    Bouville, Mathieu; Ahluwalia, Rajeev

    2006-01-01

    Materials which can undergo slow diffusive transformations as well as fast displacive transformations are studied using the phase-field method. The model captures the essential features of the time-temperature-transformation (TTT) diagrams, continuous cooling transformation (CCT) diagrams, and microstructure formation of these alloys. In some materials systems there can exist an intrinsic volume change associated with these transformations. We show that these coherency strains can stabilize m...

  1. Job strain and male fertility.

    Hjollund, Niels Henrik I; Bonde, Jens Peter E; Henriksen, Tine Brink; Giwercman, Aleksander; Olsen, Jørn

    2004-01-01

    Job strain, defined as high job demands and low job control, has not previously been explored as a possible determinant of male fertility. We collected prospective data on job strain among men, and describe the associations with semen quality and probability of conceiving a clinical pregnancy during a menstrual cycle. Danish couples (N = 399) who were trying to become pregnant for the first time were followed for up to 6 menstrual periods. All men collected semen samples, and a blood sample was drawn from both partners. Job demand and job control were measured by a self-administered questionnaire at entry, and in each cycle the participants recorded changes in job control or job demand during the previous 30 days. In adjusted analyses, no associations were found between any semen characteristic or sexual hormones and any job strain variable. The odds for pregnancy were not associated with job strain. Psychologic job strain encountered in normal jobs in Denmark does not seem to affect male reproductive function.

  2. Geographic Variation in Sexual Attraction of Spodoptera frugiperda Corn- and Rice-Strain Males to Pheromone Lures

    Unbehend, Melanie; Hänniger, Sabine; Vásquez, Gissella M.; Juárez, María Laura; Reisig, Dominic; McNeil, Jeremy N.; Meagher, Robert L.; Jenkins, David A.; Heckel, David G.; Groot, Astrid T.

    2014-01-01

    The corn- and rice-strains of Spodoptera frugiperda exhibit several genetic and behavioral differences and appear to be undergoing ecological speciation in sympatry. Previous studies reported conflicting results when investigating male attraction to pheromone lures in different regions, but this could have been due to inter-strain and/or geographic differences. Therefore, we investigated whether corn- and rice-strain males differed in their response to different synthetic pheromone blends in different regions in North America, the Caribbean and South America. All trapped males were strain-typed by two strain-specific mitochondrial DNA markers. In the first experiment, we found a nearly similar response of corn- and rice-strain males to two different 4-component blends, resembling the corn- and rice-strain female blend we previously described from females in Florida. This response showed some geographic variation in fields in Canada, North Carolina, Florida, Puerto Rico, and South America (Peru, Argentina). In dose-response experiments with the critical secondary sex pheromone component (Z)-7-dodecenyl acetate (Z7-12:OAc), we found some strain-specific differences in male attraction. While the response to Z7-12:OAc varied geographically in the corn-strain, rice-strain males showed almost no variation. We also found that the minor compound (Z)-11-hexadecenyl acetate (Z11-16:OAc) did not increase attraction of both strains in Florida and of corn-strain males in Peru. In a fourth experiment, where we added the stereo-isomer of the critical sex pheromone component, (E)-7-dodecenyl acetate, to the major pheromone component (Z)-9-tetradecenyl acetate (Z9-14:OAc), we found that this compound was attractive to males in North Carolina, but not to males in Peru. Overall, our results suggest that both strains show rather geographic than strain-specific differences in their response to pheromone lures, and that regional sexual communication differences might cause geographic

  3. Research on non-uniform strain profile reconstruction along fiber Bragg grating via genetic programming algorithm and interrelated experimental verification

    Zheng, Shijie; Zhang, Nan; Xia, Yanjun; Wang, Hongtao

    2014-03-01

    A new heuristic strategy for the non-uniform strain profile reconstruction along Fiber Bragg Gratings is proposed in this paper, which is based on the modified transfer matrix and Genetic Programming(GP) algorithm. The present method uses Genetic Programming to determine the applied strain field as a function of position along the fiber length. The structures that undergo adaptation in genetic programming are hierarchical structures which are different from that of conventional genetic algorithm operating on strings. GP regress the strain profile function which matches the 'measured' spectrum best and makes space resolution of strain reconstruction arbitrarily high, or even infinite. This paper also presents an experimental verification of the reconstruction of non-homogeneous strain fields using GP. The results are compared with numerical calculations of finite element method. Both the simulation examples and experimental results demonstrate that Genetic Programming can effectively reconstruct continuous profile expression along the whole FBG, and greatly improves its computational efficiency and accuracy.

  4. Crack tip stress and strain

    Francois, D.

    1975-01-01

    The study of potential energy variations in a loaded elastic solid containing a crack leads to determination of the crack driving force G. Generalization of this concept to cases other than linear elasticity leads to definition of the integral J. In a linear solid, the crack tip stress field is characterized by a single parameter: the stress-intensity factor K. When the crack tip plastic zone size is confined to the elastic singularity J=G, it is possible to establish relationship between these parameters and plastic strain (and in particular the crack tip opening displacement delta). The stress increases because of the triaxiality effect. This overload rises with increasing strain hardening. When the plastic zone size expands, using certain hypotheses, delta can be calculated. The plastic strain intensity is exclusively dependent on parameter J [fr

  5. Management of digital eye strain.

    Coles-Brennan, Chantal; Sulley, Anna; Young, Graeme

    2018-05-23

    Digital eye strain, an emerging public health issue, is a condition characterised by visual disturbance and/or ocular discomfort related to the use of digital devices and resulting from a range of stresses on the ocular environment. This review aims to provide an overview of the extensive literature on digital eye strain research with particular reference to the clinical management of symptoms. As many as 90 per cent of digital device users experience symptoms of digital eye strain. Many studies suggest that the following factors are associated with digital eye strain: uncorrected refractive error (including presbyopia), accommodative and vergence anomalies, altered blinking pattern (reduced rate and incomplete blinking), excessive exposure to intense light, closer working distance, and smaller font size. Since a symptom may be caused by one or more factors, a holistic approach should be adopted. The following management strategies have been suggested: (i) appropriate correction of refractive error, including astigmatism and presbyopia; (ii) management of vergence anomalies, with the aim of inducing or leaving a small amount of heterophoria (~1.5 Δ Exo); (iii) blinking exercise/training to maintain normal blinking pattern; (iv) use of lubricating eye drops (artificial tears) to help alleviate dry eye-related symptoms; (v) contact lenses with enhanced comfort, particularly at end-of-day and in challenging environments; (vi) prescription of colour filters in all vision correction options, especially blue light-absorbing filters; and (vii) management of accommodative anomalies. Prevention is the main strategy for management of digital eye strain, which involves: (i) ensuring an ergonomic work environment and practice (through patient education and the implementation of ergonomic workplace policies); and (ii) visual examination and eye care to treat visual disorders. Special consideration is needed for people at a high risk of digital eye strain, such as computer

  6. Taxonomy of oxalotrophic Methylobacterium strains

    Sahin, Nurettin; Kato, Yuko; Yilmaz, Ferah

    2008-10-01

    Most of the oxalotrophic bacteria are facultative methylotrophs and play important ecological roles in soil fertility and cycling of elements. This study gives a detailed picture of the taxonomy and diversity of these bacteria and provides new information about the taxonomical variability within the genus Methylobacterium. Twelve mesophilic, pink-pigmented, and facultatively methylotrophic oxalate-oxidizing strains were included in this work that had been previously isolated from the soil and some plant tissues by the potassium oxalate enrichment method. The isolates were characterized using biochemical tests, cellular lipid profiles, spectral characteristics of carotenoid pigments, G+C content of the DNA, and 16S rDNA sequencing. The taxonomic similarities among the strains were analyzed using the simple matching ( S SM) and Jaccard ( S J) coefficients, and the UPGMA clustering algorithm. The phylogenetic position of the strains was inferred by the neighbor-joining method on the basis of the 16S rDNA sequences. All isolates were Gram-negative, facultatively methylotrophic, oxidase and catalase positive, and required no growth factors. Based on the results of numerical taxonomy, the strains formed four closely related clusters sharing ≥85% similarity. Analysis of the 16S rDNA sequences demonstrated that oxalotrophic, pink-pigmented, and facultatively methylotrophic strains could be identified as members of the genus Methylobacterium. Except for M. variabile and M. aquaticum, all of the Methylobacterium type strains tested had the ability of oxalate utilization. Our results indicate that the capability of oxalate utilization seems to be an uncommon trait and could be used as a valuable taxonomic criterion for differentiation of Methylobacterium species.

  7. Effect of straining on diaphragmatic crura with identification of the straining-crural reflex. The "reflex theory" in gastroesophageal competence

    El Sibai Olfat

    2004-09-01

    Full Text Available Abstract Background The role of the crural diaphragm during increased intra-abdominal pressure is not exactly known. We investigated the hypothesis that the crural diaphragm undergoes reflex phasic contraction on elevation of the intra-abdominal pressure with a resulting increase of the lower esophageal pressure and prevention of gastro-esophageal reflux. Methods The esophageal pressure and crural diaphragm electromyographic responses to straining were recorded in 16 subjects (10 men, 6 women, age 36.6 ± 11.2 SD years during abdominal hernia repair. The electromyogram of crural diaphragm was recorded by needle electrode inserted into the crural diaphragm, and the lower esophageal pressure by a saline-perfused catheter. The study was repeated after crural anesthetization and after crural infiltration with saline. Results The crural diaphragm exhibited resting electromyographic activity which showed a significant increase on sudden (coughing, p Conclusions Straining effected an increase of the electromyographic activity of the crural diaphragm and of the lower esophageal pressure. This effect is suggested to be reflex in nature and to be mediated through the "straining-crural reflex". The crural diaphragm seems to play a role in the lower esophageal competence mechanism. Further studies are required to assess the clinical significance of the current results in gastro-esophageal reflux disease and hiatus hernia.

  8. Small-bowel neoplasms in patients undergoing video capsule endoscopy

    Rondonotti, E; Pennazio, M; Toth, E

    2008-01-01

    BACKGROUND AND STUDY AIM: Small-bowel tumors account for 1% - 3% of all gastrointestinal neoplasms. Recent studies with video capsule endoscopy (VCE) suggest that the frequency of these tumors may be substantially higher than previously reported. The aim of the study was to evaluate the frequency......, clinical presentation, diagnostic/therapeutic work-up, and endoscopic appearance of small-bowel tumors in a large population of patients undergoing VCE. PATIENTS AND METHODS: Identification by a questionnaire of patients with VCE findings suggesting small-bowel tumors and histological confirmation...... of the neoplasm seen in 29 centers of 10 European Countries. RESULTS: Of 5129 patients undergoing VCE, 124 (2.4%) had small-bowel tumors (112 primary, 12 metastatic). Among these patients, indications for VCE were: obscure gastrointestinal bleeding (108 patients), abdominal pain (9), search for primary neoplasm...

  9. Rosuvastatin and cardiovascular events in patients undergoing hemodialysis

    Fellström, Bengt C; Jardine, Alan G; Schmieder, Roland E

    2009-01-01

    . Secondary end points included death from all causes and individual cardiac and vascular events. RESULTS: After 3 months, the mean reduction in low-density lipoprotein (LDL) cholesterol levels was 43% in patients receiving rosuvastatin, from a mean baseline level of 100 mg per deciliter (2.6 mmol per liter......BACKGROUND: Statins reduce the incidence of cardiovascular events in patients at high cardiovascular risk. However, a benefit of statins in such patients who are undergoing hemodialysis has not been proved. METHODS: We conducted an international, multicenter, randomized, double-blind, prospective...... trial involving 2776 patients, 50 to 80 years of age, who were undergoing maintenance hemodialysis. We randomly assigned patients to receive rosuvastatin, 10 mg daily, or placebo. The combined primary end point was death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke...

  10. Estimation of organ doses of patient undergoing hepatic chemoembolization procedures

    Jaramillo, G.W.; Kramer, R.; Khoury, H.J.; Barros, V.S.M.; Andrade, G.

    2015-01-01

    The aim of this study is to evaluate the organ doses of patients undergoing hepatic chemoembolization procedures performed in two hospitals in the city of Recife-Brazil. Forty eight patients undergoing fifty hepatic chemoembolization procedures were investigated. For the 20 cases with PA projection only, organ and tissue absorbed doses as well as radiation risks were calculated. For this purpose organs and tissues dose to KAP conversion coefficients were calculated using the mesh-based phantom series FASH and MASH coupled to the EGSnrc Monte Carlo code. Clinical, dosimetric and irradiations parameters were registered for all patients. The maximum organ doses found were 1.72 Gy, 0.65Gy, 0.56 Gy and 0.33 Gy for skin, kidneys, adrenals and liver, respectively. (authors)

  11. VBAC In Women Undergoing IOL With Dinoprostone Versus Spontaneous Labor

    Alves, João; Vilhena, Cristina; Tomás, Cláudia; Antunes, Isabel Lobo; Metello, José; Natário, Isabel; Puga, Marco; Casal, Ester

    2015-01-01

    Sem PDF OBJECTIVE: To compare the rate of vaginal birth in women attempting vaginal birth after caesarean delivery (VBAC) through labour induction with dinoprostone versus a trial of spontaneous labour. METHODS: A 10-year retrospective cohort study in a tertiary care hospital of women with one prior caesarean delivery. Women who attempted VBAC with labour induction with dinoprostone were compared with women undergoing spontaneous labour. Logistic regression analyses were performed to asses...

  12. Tumor‐associated DNA mutation detection in individuals undergoing colonoscopy

    Fleshner, Phillip; Braunstein, Glenn D.; Ovsepyan, Gayane; Tonozzi, Theresa R.; Kammesheidt, Anja

    2017-01-01

    Abstract The majority of colorectal cancers (CRC) harbor somatic mutations and epigenetic modifications in the tumor tissue, and some of these mutations can be detected in plasma as circulating tumor DNA (ctDNA). Precancerous colorectal lesions also contain many of these same mutations. This study examined plasma for ctDNA from patients undergoing a screening or diagnostic colonoscopy to determine the sensitivity and specificity of the ctDNA panel for detecting CRC and precancerous lesions. T...

  13. Salivary function in patients with chronic renal failure undergoing hemodialysis

    Kaya, M.; Cermik, T.F.; Uestuen, F.; Sen, S.; Berkarda, S.

    2002-01-01

    The aim of this study was to evaluate the changes in salivary gland function in patients with chronic renal failure (CRF) undergoing hemodialysis. The group consisted of 23 patients with CRF (13 female, 10 male; mean age: 40±13 yr) and 14 healthy control subjects (mean age: 40±13 yr). All underwent dynamic salivary gland scintigraphy with gustatory stimulation. After intravenous administration of 99m Tc pertechnetate, first, perfusion images at 2 seconds per frame were acquired for 1 minute, then dynamic images at 1 minute per frame were acquired for 45 minutes. At 30 minutes after injection , 10 ml lemon juice was given for 15 minutes as a gustatory stimulus. We obtained time-activity curves derived from regions of interest centered over the four major salivary glands. The following functional indices were calculated for each gland: the time of maximum radioactivity (T max ) for the prestimulated period, the time of minimum radioactivity (T min ), as an indicator of velocity of secretion after stimulation, and the Lem E 5 % value as an indicator of the secretion function. When the patients with CRF undergoing hemodialysis were compared to the controls, there were statistically significant differences in T max , T min and Lem E 5 % values for bilateral parotid glands, and T min values for bilateral submandibular glands (p max and Lem E 5 % values for bilateral submandibular glands. There were also significant differences in T max and Lem E 5 % values for bilateral parotid glands between mild oral problems and severe oral problems in patients with CRF (undergoing hemodialysis). In this study, prolonged T max and T min values, and decreased Lem E 5 % values for parotid glands and prolonged T min values for submandibular glands on salivary scintigraphy pointed out decreased parenchymatous and excretory function in patients with CRF undergoing hemodialysis. (author)

  14. Evaluation of radiophoby phenomenon among patients undergoing radioisotope therapy

    Stepien, M.; Stepien, A.; Pawlus, J.; Wasilewska-Radwanska, M.

    2005-01-01

    The aim of study was to evaluate the radiophoby symptoms among 81 patients with different type hyperthyroidism undergoing 1-131 (450-600 MBq) treatment. The state anxiety as well as the trait anxiety levels using Spielberger's scale have been evaluated. Its values were 1 - 6 points (average 3) and 3 - 7 points (average 6) respectively for state anxiety and trait one. These results indicated that radioisotope therapy causes increase of patient's anxiety level. (author)

  15. Psychological determinants of life satisfaction in women undergoing infertility treatment

    Aleksandra Anna Dembińska

    2016-01-01

    Background Infertility treatment is a long-term process, spread out over months, or even years, and carries no guarantee of success. It generates an incessant state of uncertainty which becomes a chronic state of psychological discomfort. Each stage of treatment may become a source of more trouble. Women deciding to undergo infertility treatment are exposed to many negative feelings concerning different aspects of their life. Participants and procedure The present study wa...

  16. Nursing Care of Patients Undergoing Chemotherapy Desensitization: Part II.

    Jakel, Patricia; Carsten, Cynthia; Carino, Arvie; Braskett, Melinda

    2016-04-01

    Chemotherapy desensitization protocols are safe, but labor-intensive, processes that allow patients with cancer to receive medications even if they initially experienced severe hypersensitivity reactions. Part I of this column discussed the pathophysiology of hypersensitivity reactions and described the development of desensitization protocols in oncology settings. Part II incorporates the experiences of an academic medical center and provides a practical guide for the nursing care of patients undergoing chemotherapy desensitization.
.

  17. Local anesthesia with ropivacaine for patients undergoing laparoscopic cholecystectomy

    Liu, Yu-Yin; Yeh, Chun-Nan; Lee, Hsiang-Lin; Wang, Shang-Yu; Tsai, Chun-Yi; Lin, Chih-Chung; Chao, Tzu-Chieh; Yeh, Ta-Sen; Jan, Yi-Yin

    2009-01-01

    AIM: To investigate the effect of pain relief after infusion of ropivacaine at port sites at the end of surgery. METHODS: From October 2006 to September 2007, 72 patients undergoing laparoscopic cholecystectomy (LC) were randomized into two groups of 36 patients. One group received ropivacaine infusion at the port sites at the end of LC and the other received normal saline. A visual analog scale was used to assess postoperative pain when the patient awakened in the operating room, 6 and 24 h after surgery, and before discharge. The amount of analgesics use was also recorded. The demographics, laboratory data, hospital stay, and perioperative complications were compared between the two groups. RESULTS: There was no difference between the two groups preoperatively in terms of demographic and laboratory data. After surgery, similar operation time, blood loss, and no postoperative morbidity and mortality were observed in the two groups. However, a significantly lower pain score was observed in the patients undergoing LC with local anesthesia infusion at 1 h after LC and at discharge. Regarding analgesic use, the amount of meperidine used 1 h after LC and the total used during admission were lower in patients undergoing LC with local anesthesia infusion. This group also had a shorter hospital stay. CONCLUSION: Local anesthesia with ropivacaine at the port site in LC patients significantly decreased postoperative pain immediately. This explains the lower meperidine use and earlier discharge for these patients. PMID:19452582

  18. Predicting blood transfusion in patients undergoing minimally invasive oesophagectomy.

    Schneider, Crispin; Boddy, Alex P; Fukuta, Junaid; Groom, William D; Streets, Christopher G

    2014-12-01

    To evaluate predictors of allogenic blood transfusion requirements in patients undergoing minimal invasive oesophagectomy at a tertiary high volume centre for oesophago-gastric surgery. Retrospective analysis of all patients undergoing minimal access oesophagectomy in our department between January 2010 and December 2011. Patients were divided into two groups depending on whether they required a blood transfusion at any time during their index admission. Factors that have been shown to influence perioperative blood transfusion requirements in major surgery were included in the analysis. Binary logistic regression analysis was performed to determine the impact of patient and perioperative characteristics on transfusion requirements during the index admission. A total of 80 patients underwent minimal access oesophagectomy, of which 61 patients had a laparoscopic assisted oesophagectomy and 19 patients had a minimal invasive oesophagectomy. Perioperative blood transfusion was required in 28 patients at any time during hospital admission. On binary logistic regression analysis, a lower preoperative haemoglobin concentration (p blood transfusion requirements. It has been reported that requirement for blood transfusion can affect long-term outcomes in oesophageal cancer resection. Two factors which could be addressed preoperatively; haemoglobin concentration and type of oesophageal resection, may be valuable in predicting blood transfusions in patients undergoing minimally invasive oesophagectomy. Our analysis revealed that preoperative haemoglobin concentration, occurrence of significant complications and type of minimal access oesophagectomy predicted blood transfusion requirements in the patient population examined. Copyright © 2014 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

  19. Utility of an Australasian registry for children undergoing radiation treatment

    Ahern, Verity

    2014-01-01

    The aim of this study was to evaluate the utility of an Australasian registry ('the Registry') for children undergoing radiation treatment (RT). Children under the age of 16years who received a course of radiation between January 1997 and December 2010 and were enrolled on the Registry form the subjects of this study. A total of 2232 courses of RT were delivered, predominantly with radical intent (87%). Registrations fluctuated over time, but around one-half of children diagnosed with cancer undergo a course of RT. The most prevalent age range at time of RT was 10–15years, and the most common diagnoses were central nervous system tumours (34%) and acute lymphoblastic leukaemia (20%). The Registry provides a reflection of the patterns of care of children undergoing RT in Australia and a mechanism for determining the resources necessary to manage children by RT (human, facilities and emerging technologies, such as proton therapy). It lacks the detail to provide information on radiotherapy quality and disease outcomes which should be the subject of separate audit studies. The utility of the Registry has been hampered by its voluntary nature and varying needs for consent. Completion of registry forms is a logical requirement for inclusion in the definition of a subspecialist in paediatric radiation oncology.

  20. Carotid disease in diabetic patients undergoing coronary artery bypass grafting

    Shahid, M.; Abid, A.R.; Dar, M.A.; Noeman, A.; Amin, S.; Azhar, M.

    2012-01-01

    Objective: To compare the severity of carotid artery disease in diabetic and non-diabetic patients undergoing coronary artery bypass grafting. Methods: From January to June 2008, 379 patients undergoing elective coronary artery bypass surgery were preoperatively evaluated for the presence of carotid stenoses by duplex scanning. Patients were divided into two groups, Group I, 156 (41.2%) diabetic patients and Group II, 223 (58.8%) non-diabetic patients. Results: There were 314 (82.8%) males and 65 (17.2%) females with a mean age of 57.2+-9.1 years. In diabetic group there were 125 (80.1%) males and 31 (19.9%) females with a mean age of 56.3+-8.9 years. Left main stem stenosis was present in 59 (37.8%) diabetics and 45 (20.2%) non-diabetics (p 70% stenosis was present in 20 (5.3%) with 13 (8.3%) diabetics and 7 (3.1%) non-diabetics (p<0.025). Stenosis of 50-70% was observed in 30 (7.9%) of which 17 (10.9%) were diabetics and 13 (5.8%) were non-diabetics. Conclusion: Presence of diabetes mellitus is associated with diffuse coronary artery disease and significant carotid artery disease in patients undergoing coronary artery bypass grafting. (author)

  1. General Anaesthesia Protocols for Patients Undergoing Electroconvulsive Therapy

    Narayanan, Aravind; Lal, Chandar; Al-Sinawi, Hamed

    2017-01-01

    Objectives This study aimed to review general anaesthesia protocols for patients undergoing electroconvulsive therapy (ECT) at a tertiary care hospital in Oman, particularly with regards to clinical profile, potential drug interactions and patient outcomes. Methods This retrospective study took place at the Sultan Qaboos University Hospital (SQUH), Muscat, Oman. The electronic medical records of patients undergoing ECT at SQUH between January 2010 and December 2014 were reviewed for demographic characteristics and therapy details. Results A total of 504 modified ECT sessions were performed on 57 patients during the study period. All of the patients underwent a uniform general anaesthetic regimen consisting of propofol and succinylcholine; however, they received different doses between sessions, as determined by the treating anaesthesiologist. Variations in drug doses between sessions in the same patient could not be attributed to any particular factor. Self-limiting tachycardia and hypertension were periprocedural complications noted among all patients. One patient developed aspiration pneumonitis (1.8%). Conclusion All patients undergoing ECT received a general anaesthetic regimen including propofol and succinylcholine. However, the interplay of anaesthetic drugs with ECT efficacy could not be established due to a lack of comprehensive data, particularly with respect to seizure duration. In addition, the impact of concurrent antipsychotic therapy on anaesthetic dose and subsequent complications could not be determined. PMID:28417028

  2. Clostridium difficile colitis in patients undergoing lumbar spine surgery.

    Skovrlj, Branko; Guzman, Javier Z; Silvestre, Jason; Al Maaieh, Motasem; Qureshi, Sheeraz A

    2014-09-01

    Retrospective database analysis. To investigate incidence, comorbidities, and impact on health care resources of Clostridium difficile infection after lumbar spine surgery. C. difficile colitis is reportedly increasing in hospitalized patients and can have a negative impact on patient outcomes. No data exist on estimates of C. difficile infection rates and its consequences on patient outcomes and health care resources among patients undergoing lumbar spine surgery. The Nationwide Inpatient Sample was examined from 2002 to 2011. Patients were included for study based on International Classification of Diseases, Ninth Revision, Clinical Modification, procedural codes for lumbar spine surgery for degenerative diagnoses. Baseline patient characteristics were determined and multivariable analyses assessed factors associated with increased incidence of C. difficile and risk of mortality. The incidence of C. difficile infection in patients undergoing lumbar spine surgery is 0.11%. At baseline, patients infected with C. difficile were significantly older (65.4 yr vs. 58.9 yr, Pinfection. Small hospital size was associated with decreased odds (odds ratio [OR], 0.5; Pinfection. Uninsured (OR, 1.62; Pinfection. C. difficile increased hospital length of stay by 8 days (Pdifficile infection after lumbar spine surgery carries a 36.4-fold increase in mortality and costs approximately $10,658,646 per year to manage. These data suggest that great care should be taken to avoid C. difficile colitis in patients undergoing lumbar spine surgery because it is associated with longer hospital stays, greater overall costs, and increased inpatient mortality. 3.

  3. Stress modeling in colloidal dispersions undergoing non-viscometric flows

    Dolata, Benjamin; Zia, Roseanna

    2017-11-01

    We present a theoretical study of the stress tensor for a colloidal dispersion undergoing non-viscometric flow. In such flows, the non-homogeneous suspension stress depends on not only the local average total stresslet-the sum of symmetric first moments of both the hydrodynamic traction and the interparticle force-but also on the average quadrupole, octupole, and higher-order moments. To compute the average moments, we formulate a six dimensional Smoluchowski equation governing the microstructural evolution of a suspension in an arbitrary fluid velocity field. Under the conditions of rheologically slow flow, where the Brownian relaxation of the particles is much faster than the spatiotemporal evolution of the flow, the Smoluchowski equation permits asymptotic solution, revealing a suspension stress that follows a second-order fluid constitutive model. We obtain a reciprocal theorem and utilize it to show that all constitutive parameters of the second-order fluid model may be obtained from two simpler linear-response problems: a suspension undergoing simple shear and a suspension undergoing isotropic expansion. The consequences of relaxing the assumption of rheologically slow flow, including the appearance of memory and microcontinuum behaviors, are discussed.

  4. Mortality Among Patients with Pleural Effusion Undergoing Thoracentesis

    DeBiasi, Erin M.; Pisani, Margaret A.; Murphy, Terrence E.; Araujo, Katy; Kookoolis, Anna; Argento, A Christine; Puchalski, Jonathan

    2016-01-01

    Background Of the 1.5 million people diagnosed with pleural effusion annually in the U.S., approximately 178,000 undergo thoracentesis. While it is known that malignant pleural effusion portends a poor prognosis, mortality of patients with nonmalignant effusions has not been well studied. Methods This prospective cohort study evaluated 308 patients undergoing thoracentesis. Chart review was performed to obtain baseline characteristics. The etiology of the effusions was determined using standardized criteria. Mortality was determined at 30-days and 1-year. Results 247 unilateral and 61 bilateral thoracenteses were performed. Malignant effusion had the highest 30-day (37%) and 1 year (77%) mortality. There was substantial patient 30-day and 1-year mortality with effusions due to multiple benign etiologies (29% and 55%), CHF (22% and 53%), and renal failure (14% and 57%). Patients with bilateral pleural effusion, relative to unilateral, were associated with higher risk of death at 30 days and 1 year (17% versus 47%; HR 2.58 CI [1.44–4.63] and 36% versus 69%; HR 2.32 CI [1.55–3.48]). Conclusions Patients undergoing thoracentesis for pleural effusion have high short and long-term mortality. Patients with malignant effusion had the highest mortality followed by multiple benign etiologies, CHF and renal failure. Bilateral pleural effusion is distinctly associated with high mortality. PMID:25837039

  5. Noncontacting-optical-strain device

    Silver, R. H.

    1970-01-01

    Noncontacting-strain-measuring gauge and extensometer remotely measures the mechanical displacement along the entire length of a test specimen. Measurement is accomplished by continuous scanning of a reflected light from reflective bench markings or stripes previously affixed to the specimen.

  6. Job strain and tobacco smoking

    Heikkilä, Katriina; Nyberg, Solja T; Fransson, Eleonor I

    2012-01-01

    Tobacco smoking is a major contributor to the public health burden and healthcare costs worldwide, but the determinants of smoking behaviours are poorly understood. We conducted a large individual-participant meta-analysis to examine the extent to which work-related stress, operationalised as job...... strain, is associated with tobacco smoking in working adults....

  7. Strain effects in oxide superconductors

    Wada, H.; Kuroda, T.; Sekine, H.; Yuyama, M.; Itoh, K.

    1991-01-01

    Strain sensitivities of superconducting properties are critical to high magnetic field applications of superconductors, since critical temperature, T c , upper critical field, H c2 , and critical current (density), I c (J c ), are all degraded under strains. Oxide superconductors so far known are all very fragile, thus requiring to be fabricated in the form of composite. In the case of practical metallic superconductors, such as Nb 3 Sn and V 3 Ga, the so-called bronze method has been developed where these superconducting intermetallics are enveloped in a ductile metallic sheath. Recently, a fabrication method similar to the bronze method has been developed for the Bi 2 Sr 2 Ca 2 Cu 3 O x superconductors using Ag tubes as sheath. In the present study mono- and multicore BiPbSrCaCuO tape conductors were prepared by means of this Ag-sheath composite method, and examined in terms of strain sensitivity by measuring their T c and I c (J c ) under bending or tensile strains. (orig.)

  8. Mobilomics in Saccharomyces cerevisiae strains.

    Menconi, Giulia; Battaglia, Giovanni; Grossi, Roberto; Pisanti, Nadia; Marangoni, Roberto

    2013-03-20

    Mobile Genetic Elements (MGEs) are selfish DNA integrated in the genomes. Their detection is mainly based on consensus-like searches by scanning the investigated genome against the sequence of an already identified MGE. Mobilomics aims at discovering all the MGEs in a genome and understanding their dynamic behavior: The data for this kind of investigation can be provided by comparative genomics of closely related organisms. The amount of data thus involved requires a strong computational effort, which should be alleviated. Our approach proposes to exploit the high similarity among homologous chromosomes of different strains of the same species, following a progressive comparative genomics philosophy. We introduce a software tool based on our new fast algorithm, called regender, which is able to identify the conserved regions between chromosomes. Our case study is represented by a unique recently available dataset of 39 different strains of S.cerevisiae, which regender is able to compare in few minutes. By exploring the non-conserved regions, where MGEs are mainly retrotransposons called Tys, and marking the candidate Tys based on their length, we are able to locate a priori and automatically all the already known Tys and map all the putative Tys in all the strains. The remaining putative mobile elements (PMEs) emerging from this intra-specific comparison are sharp markers of inter-specific evolution: indeed, many events of non-conservation among different yeast strains correspond to PMEs. A clustering based on the presence/absence of the candidate Tys in the strains suggests an evolutionary interconnection that is very similar to classic phylogenetic trees based on SNPs analysis, even though it is computed without using phylogenetic information. The case study indicates that the proposed methodology brings two major advantages: (a) it does not require any template sequence for the wanted MGEs and (b) it can be applied to infer MGEs also for low coverage genomes

  9. Mobilomics in Saccharomyces cerevisiae strains

    2013-01-01

    Background Mobile Genetic Elements (MGEs) are selfish DNA integrated in the genomes. Their detection is mainly based on consensus–like searches by scanning the investigated genome against the sequence of an already identified MGE. Mobilomics aims at discovering all the MGEs in a genome and understanding their dynamic behavior: The data for this kind of investigation can be provided by comparative genomics of closely related organisms. The amount of data thus involved requires a strong computational effort, which should be alleviated. Results Our approach proposes to exploit the high similarity among homologous chromosomes of different strains of the same species, following a progressive comparative genomics philosophy. We introduce a software tool based on our new fast algorithm, called regender, which is able to identify the conserved regions between chromosomes. Our case study is represented by a unique recently available dataset of 39 different strains of S.cerevisiae, which regender is able to compare in few minutes. By exploring the non–conserved regions, where MGEs are mainly retrotransposons called Tys, and marking the candidate Tys based on their length, we are able to locate a priori and automatically all the already known Tys and map all the putative Tys in all the strains. The remaining putative mobile elements (PMEs) emerging from this intra–specific comparison are sharp markers of inter–specific evolution: indeed, many events of non–conservation among different yeast strains correspond to PMEs. A clustering based on the presence/absence of the candidate Tys in the strains suggests an evolutionary interconnection that is very similar to classic phylogenetic trees based on SNPs analysis, even though it is computed without using phylogenetic information. Conclusions The case study indicates that the proposed methodology brings two major advantages: (a) it does not require any template sequence for the wanted MGEs and (b) it can be applied to

  10. Impact of multimodal preoperative preparation program on children undergoing surgery

    Priya Reshma Aranha

    2017-01-01

    Full Text Available Background: The advanced era of technological development in child health care has resulted in more pediatric procedures being performed in various settings. Millions of children undergo surgery every year which is a stressful event. Many nonpharmacological strategies are being used to manage the preoperative fear and anxiety in children. The current study aims to assess the effectiveness of multimodal preoperative preparation program (MPPP on children undergoing surgery in terms of its effect on the psychophysiological parameters. Objective: The aim of this study is to assess the effectiveness of MPPP on the psychophysiological parameters of children undergoing surgery. Materials and Methods: A quasi-experimental study was conducted in a selected multi-specialty hospital. Using the purposive sampling technique, a total of 110 children aged 8–12 years were assigned to nonintervention (n = 55 and intervention (n = 55 groups, respectively. The MPPP was administered to the intervention group. The children in the nonintervention group received the routine preoperative care. Child's fear and anxiety was assessed on admission, prior to shifting the child to operation theater (OT, 24 and 48 h after surgery, whereas child's pulse, respiration, blood pressure (BP, and oxygen saturation was assessed on admission, prior to shifting the child to OT, 6, 12, 24, and 48 h after surgery and pain was assessed at 24 and 48 h after surgery. Results: The mean fear and anxiety scores of children were significantly lower in the intervention group than that of nonintervention group (P 0.05. This study also found that there is a significant association between the psychophysiological parameters of children with the selected demographic variables (P < 0.05. A positive correlation was found between the psychological and physiological parameters of children undergoing surgery. Conclusion: The MPPP is effective on psychophysiological parameters of children undergoing

  11. A NEW STRAIN OF TRANSMISSIBLE LEUCEMIA IN FOWLS (STRAIN H).

    Ellermann, V

    1921-03-31

    1. A new strain of fowl leucosis has been transmitted through twelve generations of fowls. 2. An increase in virulence was observed during its passage. This was shown in a shortening of the interval between inoculation and death. The increase in virulence does not affect the number of successful inoculations, which remains approximately constant in from 20 to 40 per cent of the birds employed. 3. As with former strains, the disease manifests itself in various forms; i.e., myeloid and intravascular lymphoid types. A single lymphatic case was observed. 4. In several intravascular cases a diminution in the hemolytic power of the serum was established. This phenomenon was absent in a number of myeloid cases. 5. Active immunization cannot be produced by means of the subcutaneous injection of virulent material. 6. The finding of previous experiments that the virus is filterable has been confirmed. 7. The inoculation of human leucemic material into fowls gave negative results.

  12. Effect of Cr and Mo on strain ageing behaviour of low carbon steel

    Pereloma, E.V.; Bata, V.; Scott, R.I.; Smith, R.M.

    2010-01-01

    This work explores the effects of Cr (0.26-0.74 wt%) and Mo (0.09-0.3 wt%) additions on the kinetics of strain ageing process in low carbon steel. The strain ageing behaviour of the steels was investigated by using tensile tests and transmission electron microscopy. The results have shown that Mo-alloyed steels undergo the same four stages of ageing as unalloyed low carbon steel, whereas Cr-alloyed steels exhibit only three stages of ageing. At the same time, the addition of Mo accelerates the ageing response, while alloying with Cr reduces the rate of strain ageing by ∼3 times in comparison with non-alloyed low carbon steel. It especially delays the offset of Stage III. This is explained by the reduction of carbon content in ferrite due to the enrichment of cementite with Cr leading to the reduction of its equilibrium solubility in ferrite.

  13. Effect of Cr and Mo on strain ageing behaviour of low carbon steel

    Pereloma, E.V., E-mail: elenap@uow.edu.au [School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522 (Australia); Bata, V. [Department of Materials Engineering, Monash University (Australia); Scott, R.I.; Smith, R.M. [BlueScope Steel Limited, Port Kembla (Australia)

    2010-04-25

    This work explores the effects of Cr (0.26-0.74 wt%) and Mo (0.09-0.3 wt%) additions on the kinetics of strain ageing process in low carbon steel. The strain ageing behaviour of the steels was investigated by using tensile tests and transmission electron microscopy. The results have shown that Mo-alloyed steels undergo the same four stages of ageing as unalloyed low carbon steel, whereas Cr-alloyed steels exhibit only three stages of ageing. At the same time, the addition of Mo accelerates the ageing response, while alloying with Cr reduces the rate of strain ageing by {approx}3 times in comparison with non-alloyed low carbon steel. It especially delays the offset of Stage III. This is explained by the reduction of carbon content in ferrite due to the enrichment of cementite with Cr leading to the reduction of its equilibrium solubility in ferrite.

  14. Strain modulations as a mechanism to reduce stress relaxation in laryngeal tissues.

    Hunter, Eric J; Siegmund, Thomas; Chan, Roger W

    2014-01-01

    Vocal fold tissues in animal and human species undergo deformation processes at several types of loading rates: a slow strain involved in vocal fold posturing (on the order of 1 Hz or so), cyclic and faster posturing often found in speech tasks or vocal embellishment (1-10 Hz), and shear strain associated with vocal fold vibration during phonation (100 Hz and higher). Relevant to these deformation patterns are the viscous properties of laryngeal tissues, which exhibit non-linear stress relaxation and recovery. In the current study, a large strain time-dependent constitutive model of human vocal fold tissue is used to investigate effects of phonatory posturing cyclic strain in the range of 1 Hz to 10 Hz. Tissue data for two subjects are considered and used to contrast the potential effects of age. Results suggest that modulation frequency and extent (amplitude), as well as the amount of vocal fold overall strain, all affect the change in stress relaxation with modulation added. Generally, the vocal fold cover reduces the rate of relaxation while the opposite is true for the vocal ligament. Further, higher modulation frequencies appear to reduce the rate of relaxation, primarily affecting the ligament. The potential benefits of cyclic strain, often found in vibrato (around 5 Hz modulation) and intonational inflection, are discussed in terms of vocal effort and vocal pitch maintenance. Additionally, elderly tissue appears to not exhibit these benefits to modulation. The exacerbating effect such modulations may have on certain voice disorders, such as muscle tension dysphonia, are explored.

  15. Resurgence of canine parvovirus 2a strain in the domestic dog population from Argentina.

    Calderón, Marina Gallo; Romanutti, Carina; Wilda, Maximiliano; D' Antuono, Alejandra; Keller, Leticia; Giacomodonato, Mónica N; Mattion, Nora; La Torre, José

    2015-09-15

    Ninety-three rectal swab samples were taken, from dogs suspected of canine parvovirus (CPV) infection and analyzed by PCR. A fragment of the VP2 gene, was amplified in 41 (44%) of them, resulting CPV positive samples. Sequencing analysis of these PCR products showed that 37 samples (90.2%) belonged to the CPV2c type, whereas four samples (9.8%) were identified as CPV2a, which has not been found since 2008. It was also found that 24 out of 37 CPV2c samples (65%), carried the mutation Thr440Ala, whereas this mutation was absent in the four CPV2a strains reported herein. Using phylogenetic analysis of the full length VP2 gene, which was amplified by PCR in six local samples, it was seen that CPV2a Argentine strains reported in this study, were genetically closer to a previous local CPV2a isolate (year 2003) and to a South African CPV2a strain, than to any of the recently reported Uruguayan CPV2a strains. The results obtained in this work, together with those reported previously in Uruguay strongly suggest that, in spite of the geographical proximity, wild type CPV strains undergo different evolutive pathways in each country, resulting in the prevalence of different strains in related dog populations. Further extensive epidemiological studies are needed in order to improve the understanding of CPV evolution. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Compressive strain induced enhancement in thermoelectric-power-factor in monolayer MoS2 nanosheet

    Dimple; Jena, Nityasagar; De Sarkar, Abir

    2017-01-01

    Strain and temperature induced tunability in the thermoelectric properties in monolayer MoS 2 (ML-MoS 2 ) has been demonstrated using density functional theory coupled to semi-classical Boltzmann transport theory. Compressive strain, in general and uniaxial compressive strain (along the zig-zag direction), in particular, is found to be most effective in enhancing the thermoelectric power factor, owing to the higher electronic mobility and its sensitivity to lattice compression along this direction. Variation in the Seebeck coefficient and electronic band gap with strain is found to follow the Goldsmid–Sharp relation. n-type doping is found to raise the relaxation time-scaled thermoelectric power factor higher than p-type doping and this divide widens with increasing temperature. The relaxation time-scaled thermoelectric power factor in optimally n-doped ML-MoS 2 is found to undergo maximal enhancement under the application of 3% uniaxial compressive strain along the zig-zag direction, when both the ( direct ) electronic band gap and the Seebeck coefficient reach their maximum, while the electron mobility drops down drastically from 73.08 to 44.15 cm 2 V −1 s −1 . Such strain sensitive thermoelectric responses in ML-MoS 2 could open doorways for a variety of applications in emerging areas in 2D-thermoelectrics, such as on-chip thermoelectric power generation and waste thermal energy harvesting. (paper)

  17. Analysis of the genetic variation in Mycobacterium tuberculosis strains by multiple genome alignments

    Morales Juan

    2008-11-01

    Full Text Available Abstract Background The recent determination of the complete nucleotide sequence of several Mycobacterium tuberculosis (MTB genomes allows the use of comparative genomics as a tool for dissecting the nature and consequence of genetic variability within this species. The multiple alignment of the genomes of clinical strains (CDC1551, F11, Haarlem and C, along with the genomes of laboratory strains (H37Rv and H37Ra, provides new insights on the mechanisms of adaptation of this bacterium to the human host. Findings The genetic variation found in six M. tuberculosis strains does not involve significant genomic rearrangements. Most of the variation results from deletion and transposition events preferentially associated with insertion sequences and genes of the PE/PPE family but not with genes implicated in virulence. Using a Perl-based software islandsanalyser, which creates a representation of the genetic variation in the genome, we identified differences in the patterns of distribution and frequency of the polymorphisms across the genome. The identification of genes displaying strain-specific polymorphisms and the extrapolation of the number of strain-specific polymorphisms to an unlimited number of genomes indicates that the different strains contain a limited number of unique polymorphisms. Conclusion The comparison of multiple genomes demonstrates that the M. tuberculosis genome is currently undergoing an active process of gene decay, analogous to the adaptation process of obligate bacterial symbionts. This observation opens new perspectives into the evolution and the understanding of the pathogenesis of this bacterium.

  18. The position of the cancer patient undergoing radiotherapy -psychological and physical aspects

    Frischenschlager, O.; Hohenberg, G.; Handl-Zeller, L.

    1991-01-01

    This study examines the psychological strains experienced by patients undergoing radiotherapy, as well as their somatic complaints and the possible connection between these two aspects. The sample consisted of 87 cancer patients, 64 female, 23 male. We used two standardized clinical instruments, one Zerssen's list of somatic complaints ('Beschwerdeliste' in German) and Zerssen's questionnaire of wellbeing ('Befindlichkeitsskala' in German). These two research instruments were implemented four times: at the beginning, in the middle and at the end of radiation, and three month afterwards. Results: Both the psychological state of well-being and somatic complaints remained at approximately the same level during the whole course of therapy. The state of well-being increased significantly after therapy, which is indicated by the decrease in the number of psychological impairments, whereas the score for somatic complaints remained the same. We observed a general tendency on the part of the patients to play down their situation. Sex differences were not observed. The discussion of the results includes their implication on the doctor-patient relationship. (Author)

  19. Effect of clindamycin prophylaxis on the colonic microflora in patients undergoing colorectal surgery.

    Kager, L; Liljeqvist, L; Malmborg, A S; Nord, C E

    1981-12-01

    Clindamycin was given intravenously to 15 patients undergoing colorectal surgery in an initial dose of 600 mg, given at induction of anesthesia followed by 6 doses of 600 mg at 8-h intervals. Series of serum samples and fecal specimens were taken for analysis of clindamycin concentrations. Tissue samples from the gut wall were taken at surgery. The highest serum concentrations observed occurred 30 min after administration of clindamycin and varied between 6.8 and 37.9 microgram/ml (mean, 14.8 +/- 2.0 [standard error] microgram/ml). The clindamycin concentrations in the tissue samples were between 1.8 and 13.0 microgram/g. Clindamycin concentration in the fecal samples varied between 2.1 and 460 microgram/g. Fecal samples were also collected during the investigation period for cultivation of aerobic and anaerobic bacteria. Among the aerobic bacteria, enterococci and streptococci decreased during the prophylaxis period. Anaerobic bacteria also decreased significantly during the same period. After the clindamycin administration period, enterococci, streptococci and anaerobic bacteria proliferated. No anaerobic strains resistant to clindamycin were isolated. Postoperative infections due to Streptococcus faecalis and different enterobacteria such as Escherichia coli, Enterobacter cloacae, Citrobacter freundii, and Klebsiella occurred in five patients.

  20. Gram-positive rods prevailing in teeth with apical periodontitis undergoing root canal treatment.

    Chávez de Paz, L E; Molander, A; Dahlén, G

    2004-09-01

    To identify Gram-positive rods from root canals of teeth with apical periodontitis and to examine their associations with other species. Consecutive root canal samples (RCSs) from 139 teeth undergoing root canal treatment were analyzed prospectively for cultivable microbes. Gram-positive rods in the first RCS submitted after chemo-mechanical preparation were categorised to genus level by selective media and gas-liquid chromatography (GLC), and identified to species level by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Associations between organisms were measured by odds ratios (OR). In the first samples submitted a total of 158 Gram-positive rods, 115 Gram-positive cocci, 26 Gram-negative rods and 9 Gram-negative cocci, were identified. At genus levels Gram-positive rods were classified into: Lactobacillus spp. (38%), Olsenella spp. (18%), Propionibacterium spp. (13%), Actinomyces spp. (12%), Bifidobacterium spp. (13%) and Eubacterium spp. (6%). The most frequent species were Olsenella uli, Lactobacillus paracasei and Propionibacterium propionicum. In subsequent samples taken during treatment, Gram-positive rods were also identified, although the number of strains was considerably reduced. Positive associations were observed between members of the genus lactobacilli and Gram-positive cocci (OR>2). Olsenella uli and Lactobacillus spp. predominated over other Gram-positive rods. A possible association exists between Lactobacillus spp. and Gram-positive cocci in root canals of teeth with apical periodontitis receiving treatment.

  1. Computational strain gradient crystal plasticity

    Niordson, Christian Frithiof; Kysar, Jeffrey W.

    2014-01-01

    A numerical method for viscous strain gradient crystal plasticity theory is presented, which incorporates both energetic and dissipative gradient effects. The underlying minimum principles are discussed as well as convergence properties of the proposed finite element procedure. Three problems...... of plane crystal plasticity are studied: pure shear of a single crystal between rigid platens as well as plastic deformation around cylindrical voids in hexagonal close packed and face centered cubic crystals. Effective in-plane constitutive slip parameters for plane strain deformation of specifically...... oriented face centered cubic crystals are developed in terms of the crystallographic slip parameters. The effect on geometrically necessary dislocation structures introduced by plastic deformation is investigated as a function of the ratio of void radius to plasticity length scale....

  2. Impact of Right Ventricular Performance in Patients Undergoing Extracorporeal Membrane Oxygenation Following Cardiac Surgery.

    Bartko, Philipp E; Wiedemann, Dominik; Schrutka, Lore; Binder, Christina; Santos-Gallego, Carlos G; Zuckermann, Andreas; Steinlechner, Barbara; Koinig, Herbert; Heinz, Gottfried; Niessner, Alexander; Zimpfer, Daniel; Laufer, Günther; Lang, Irene M; Distelmaier, Klaus; Goliasch, Georg

    2017-07-28

    Extracorporeal membrane oxygenation following cardiac surgery safeguards end-organ oxygenation but unfavorably alters cardiac hemodynamics. Along with the detrimental effects of cardiac surgery to the right heart, this might impact outcome, particularly in patients with preexisting right ventricular (RV) dysfunction. We sought to determine the prognostic impact of RV function and to improve established risk-prediction models in this vulnerable patient cohort. Of 240 patients undergoing extracorporeal membrane oxygenation support following cardiac surgery, 111 had echocardiographic examinations at our institution before implantation of extracorporeal membrane oxygenation and were thus included. Median age was 67 years (interquartile range 60-74), and 74 patients were male. During a median follow-up of 27 months (interquartile range 16-63), 75 patients died. Fifty-one patients died within 30 days, 75 during long-term follow-up (median follow-up 27 months, minimum 5 months, maximum 125 months). Metrics of RV function were the strongest predictors of outcome, even stronger than left ventricular function ( P <0.001 for receiver operating characteristics comparisons). Specifically, RV free-wall strain was a powerful predictor univariately and after adjustment for clinical variables, Simplified Acute Physiology Score-3, tricuspid regurgitation, surgery type and duration with adjusted hazard ratios of 0.41 (95%CI 0.24-0.68; P =0.001) for 30-day mortality and 0.48 (95%CI 0.33-0.71; P <0.001) for long-term mortality for a 1-SD (SD=-6%) change in RV free-wall strain. Combined assessment of the additive EuroSCORE and RV free-wall strain improved risk classification by a net reclassification improvement of 57% for 30-day mortality ( P =0.01) and 56% for long-term mortality ( P =0.02) compared with the additive EuroSCORE alone. RV function is strongly linked to mortality, even after adjustment for baseline variables and clinical risk scores. RV performance improves

  3. An interactive videogame designed to improve respiratory navigator efficiency in children undergoing cardiovascular magnetic resonance.

    Hamlet, Sean M; Haggerty, Christopher M; Suever, Jonathan D; Wehner, Gregory J; Grabau, Jonathan D; Andres, Kristin N; Vandsburger, Moriel H; Powell, David K; Sorrell, Vincent L; Fornwalt, Brandon K

    2016-09-06

    Advanced cardiovascular magnetic resonance (CMR) acquisitions often require long scan durations that necessitate respiratory navigator gating. The tradeoff of navigator gating is reduced scan efficiency, particularly when the patient's breathing patterns are inconsistent, as is commonly seen in children. We hypothesized that engaging pediatric participants with a navigator-controlled videogame to help control breathing patterns would improve navigator efficiency and maintain image quality. We developed custom software that processed the Siemens respiratory navigator image in real-time during CMR and represented diaphragm position using a cartoon avatar, which was projected to the participant in the scanner as visual feedback. The game incentivized children to breathe such that the avatar was positioned within the navigator acceptance window (±3 mm) throughout image acquisition. Using a 3T Siemens Tim Trio, 50 children (Age: 14 ± 3 years, 48 % female) with no significant past medical history underwent a respiratory navigator-gated 2D spiral cine displacement encoding with stimulated echoes (DENSE) CMR acquisition first with no feedback (NF) and then with the feedback game (FG). Thirty of the 50 children were randomized to undergo extensive off-scanner training with the FG using a MRI simulator, or no off-scanner training. Navigator efficiency, signal-to-noise ratio (SNR), and global left-ventricular strains were determined for each participant and compared. Using the FG improved average navigator efficiency from 33 ± 15 to 58 ± 13 % (p < 0.001) and improved SNR by 5 % (p = 0.01) compared to acquisitions with NF. There was no difference in navigator efficiency (p = 0.90) or SNR (p = 0.77) between untrained and trained participants for FG acquisitions. Circumferential and radial strains derived from FG acquisitions were slightly reduced compared to NF acquisitions (-16 ± 2 % vs -17 ± 2 %, p < 0.001; 40 ± 10

  4. Tranexamic Acid in Patients Undergoing Coronary-Artery Surgery.

    Myles, Paul S; Smith, Julian A; Forbes, Andrew; Silbert, Brendan; Jayarajah, Mohandas; Painter, Thomas; Cooper, D James; Marasco, Silvana; McNeil, John; Bussières, Jean S; McGuinness, Shay; Byrne, Kelly; Chan, Matthew T V; Landoni, Giovanni; Wallace, Sophie

    2017-01-12

    Tranexamic acid reduces the risk of bleeding among patients undergoing cardiac surgery, but it is unclear whether this leads to improved outcomes. Furthermore, there are concerns that tranexamic acid may have prothrombotic and proconvulsant effects. In a trial with a 2-by-2 factorial design, we randomly assigned patients who were scheduled to undergo coronary-artery surgery and were at risk for perioperative complications to receive aspirin or placebo and tranexamic acid or placebo. The results of the tranexamic acid comparison are reported here. The primary outcome was a composite of death and thrombotic complications (nonfatal myocardial infarction, stroke, pulmonary embolism, renal failure, or bowel infarction) within 30 days after surgery. Of the 4662 patients who were enrolled and provided consent, 4631 underwent surgery and had available outcomes data; 2311 were assigned to the tranexamic acid group and 2320 to the placebo group. A primary outcome event occurred in 386 patients (16.7%) in the tranexamic acid group and in 420 patients (18.1%) in the placebo group (relative risk, 0.92; 95% confidence interval, 0.81 to 1.05; P=0.22). The total number of units of blood products that were transfused during hospitalization was 4331 in the tranexamic acid group and 7994 in the placebo group (Ptranexamic acid group and in 2.8% of the patients in the placebo group (P=0.001), and seizures occurred in 0.7% and 0.1%, respectively (P=0.002 by Fisher's exact test). Among patients undergoing coronary-artery surgery, tranexamic acid was associated with a lower risk of bleeding than was placebo, without a higher risk of death or thrombotic complications within 30 days after surgery. Tranexamic acid was associated with a higher risk of postoperative seizures. (Funded by the Australian National Health and Medical Research Council and others; ATACAS Australia New Zealand Clinical Trials Registry number, ACTRN12605000557639 .).

  5. [The health of adults undergoing an eviction process].

    Bolívar Muñoz, Julia; Bernal Solano, Mariola; Mateo Rodríguez, Inmaculada; Daponte Codina, Antonio; Escudero Espinosa, Cecilia; Sánchez Cantalejo, Carmen; González Usera, Isis; Robles Ortega, Humbelina; Mata Martín, José Luis; Fernández Santaella, M Carmen; Vila Castellar, Jaime

    2016-01-01

    To analyze perceived health status and other health-related indicators in the adult population in Granada (Spain) undergoing an eviction process from their homes, whether rented or owned, in comparison with health indicators in the general adult population in Andalusia. A cross-sectional survey was administered by trained staff. The survey included instruments from the Andalusian Health Survey 2011 for measuring variables related to physical and mental health, as well as health-related habits. We compared the results with those obtained from the Andalusian general population through the Andalusian Health Survey. A bivariate analysis using the χ2 test and a multivariate logistic regression analysis were conducted. We obtained a total sample of 205 people in the process of eviction. A total of 59.5% (n=122) were women, and 40.5% (n=83) were men. Participants were more likely to have poor health (odds ratio [OR]: 12.63, 95% confidence interval [95%CI]: 8.74-18.27), have cardiovascular diseases (OR: 3.08; 95%CI: 1.54- 6.16), or to smoke (OR: 1.68; 95% CI: 1.21-2.33) compared with the Andalusian general population. Most of the health indicators analyzed showed a worse outcome for women undergoing an eviction process. Our results suggest that, in the current context of economic crisis, people undergoing a process of eviction in Granada and its metropolitan area show poorer health than the Andalusian general population. Further research is needed on health and evictions from different methodological approaches, for a better understanding of the topic. Copyright © 2015 SESPAS. Published by Elsevier Espana. All rights reserved.

  6. Oral Triiodothyronine for Infants and Children Undergoing Cardiopulmonary Bypass.

    Marwali, Eva M; Boom, Cindy E; Budiwardhana, Novik; Fakhri, Dicky; Roebiono, Poppy S; Santoso, Anwar; Sastroasmoro, Sudigdo; Slee, April; Portman, Michael A

    2017-08-01

    This study evaluated the efficacy and safety of oral triiodothyronine (T3; Tetronine, Dalim BioTech, Korea) for infants and children undergoing cardiopulmonary bypass in an Indonesian population. We performed a single-center, randomized, double-blind, and placebo-controlled trial in children aged 3 years and younger undergoing congenital heart disease operations with cardiopulmonary bypass. We administered oral T3 (1 μg/kg per body weight/dose) or placebo (saccharum lactis) by nasogastric tube every 6 hours for 60 hours after induction of anesthesia. The primary end point, time to extubation, was compared with Cox regression. The modified intention-to-treat group included 101 placebo and 104 treated patients. The stratified log-rank test did not show a significant treatment difference (p = 0.061) for time to extubation, but after adjustment for age, the nutritional Z score, and Aristotle surgical complexity, the hazard ratio was 1.33 (95% confidence interval, 1.00 to 1.76; p = 0.049). The effect of T3 was stronger in the strata aged 5 months and younger (hazard ratio, 1.86; 95% confidence interval 1.02 to 3.39; p = 0.043). Median intubation time was 47.3 hours for the placebo and 32.1 hours for the T3 group in aged 5 months and younger. Adverse events rates, including arrhythmia, were similar between groups, although sepsis was more frequent with placebo. Oral T3 supplementation may shorten time to extubation in children undergoing congenital heart disease operations, particularly infants aged 5 months or younger. Administration is relatively safe, simple and inexpensive. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  7. Cerebroprotective effect of piracetam in patients undergoing open heart surgery.

    Holinski, Sebastian; Claus, Benjamin; Alaaraj, Nour; Dohmen, Pascal Maria; Neumann, Konrad; Uebelhack, Ralf; Konertz, Wolfgang

    2011-01-01

    Reduction of cognitive function is a possible side effect after the use of cardiopulmonary bypass (CPB) during cardiac surgery. Since it has been proven that piracetam is cerebroprotective in patients undergoing coronary bypass surgery, we investigated the effects of piracetam on the cognitive performance of patients undergoing open heart surgery. Patients scheduled for elective open heart surgery were randomized to the piracetam or placebo group in a double-blind study. Patients received 12 g of piracetam or placebo at the beginning of the operation. Six neuropsychological subtests from the Syndrom Kurz Test and the Alzheimer's Disease Assessment Scale were performed preoperatively and on day 3, postoperatively. To assess the overall cognitive function and the degree of cognitive decline across all tests after the surgery, we combined the six test-scores by principal component analysis. A total of 88 patients with a mean age of 67 years were enrolled into the study. The mean duration of CPB was 110 minutes. Preoperative clinical parameters and overall cognitive functions were not significantly different between the groups. The postoperative combined score of the neuropsychological tests showed deterioration of cognitive function in both groups (piracetam: preoperative 0.19 ± 0.97 vs. postoperative -0.97 ± 1.38, p piracetam did not perform better than those taking placebo, and both groups had the same decline of overall cognitive function (p = 0.955). Piracetam had no cerebroprotective effect in patients undergoing open heart surgery. Unlike the patients who underwent coronary surgery, piracetam did not reduce the early postoperative decline of neuropsychological abilities in heart valve patients.

  8. Strain-Detecting Composite Materials

    Wallace, Terryl A. (Inventor); Smith, Stephen W. (Inventor); Piascik, Robert S. (Inventor); Horne, Michael R. (Inventor); Messick, Peter L. (Inventor); Alexa, Joel A. (Inventor); Glaessgen, Edward H. (Inventor); Hailer, Benjamin T. (Inventor)

    2016-01-01

    A composite material includes a structural material and a shape-memory alloy embedded in the structural material. The shape-memory alloy changes crystallographic phase from austenite to martensite in response to a predefined critical macroscopic average strain of the composite material. In a second embodiment, the composite material includes a plurality of particles of a ferromagnetic shape-memory alloy embedded in the structural material. The ferromagnetic shape-memory alloy changes crystallographic phase from austenite to martensite and changes magnetic phase in response to the predefined critical macroscopic average strain of the composite material. A method of forming a composite material for sensing the predefined critical macroscopic average strain includes providing the shape-memory alloy having an austenite crystallographic phase, changing a size and shape of the shape-memory alloy to thereby form a plurality of particles, and combining the structural material and the particles at a temperature of from about 100-700.degree. C. to form the composite material.

  9. Internal flow of acoustically levitated drops undergoing sectorial oscillations

    Shen, C.L.; Xie, W.J.; Yan, Z.L.; Wei, B.

    2010-01-01

    We present the experimental observation and theoretical analysis of fluid flow in acoustically levitated water drop undergoing sectorial oscillations. The fluid always flows between the extended sections and the compressed sections. The magnitude of fluid velocity decreases from the equatorial fringe to the centre of levitated drop. The maximum fluid velocity is 60-160 mm/s and the Reynolds number of the oscillations is estimated to be 137-367. The internal flow of the drop is analyzed as potential flow, and the fluid velocity is found to be horizontal. In the equatorial plane, the calculated stream lines and velocity profiles agree well with the experimental observations.

  10. Nutrient content of sorghum beer strainings

    Sorghum beer strainings were analysed for starch, protein, fat, crude fibre, ash, minerals and ... The importance of minerals in animal nutrition has been recognized for many ..... strainings is probably due to yeast activity during fermentation ...

  11. Yeast strains and methods of use thereof

    Goddard, Matthew Robert; Gardner, Richard Clague; Anfang, Nicole

    2013-01-01

    The present invention relates to yeast strains and, in particular, to yeast stains for use in fermentation processes. The invention also relates to methods of fermentation using the yeast strains of the invention either alone or in combination with other yeast strains. The invention thither relates to methods for the selection of yeast strains suitable for fermentation cultures by screening for various metabolic products and the use of specific nutrient sources.

  12. Development of Industrial Yeast Platform Strains

    Bergdahl, Basti; Dato, Laura; Förster, Jochen

    2014-01-01

    Most of the current metabolic engineering projects are carried out using laboratory strains as the starting host. Although such strains are easily manipulated genetically, their robustness does not always meet the requirements set by industrial fermentation conditions. In such conditions, the cells...... screening of the 36 industrial and laboratory yeast strains. In addition, progress in the development of molecular biology methods for generating the new strains will be presented....

  13. STRAINED OFF BREAST MILK: PRO AND CONTRA

    O.L. Lukoyanova

    2010-01-01

    Full Text Available The questions of feeding of children with strained off breast milk are discussed in this article. Author presents medical indications to such type of feeding, peculiarities and rules of storage of strained off milk. There is a brief literature review on the influence of different factors on the composition of strained off breast milk.Key words: strained milk, breast feeding, pasteurization, freezing.(Voprosy sovremennoi pediatrii — Current Pediatrics. 2010;9(2:70-73

  14. Tailoring the structural and electronic properties of a graphene-like ZnS monolayer using biaxial strain

    Behera, Harihar; Mukhopadhyay, Gautam

    2014-01-01

    Our first-principles full-potential density functional theory calculations show that a ZnS monolayer (ML-ZnS), which is predicted to adopt a graphene-like planar honeycomb structure with a direct band gap, undergoes strain-induced modifications in its structure and band gap when subjected to in-plane homogeneous biaxial strain (δ). ML-ZnS gets buckled for compressive strain greater than 0.92% ; the buckling parameter Δ(= 0.00 Å for planar ML-ZnS) linearly increases with increasing compressive strain (Δ = 0.435 Å at δ = −5.25%). A tensile strain of 2.91% turns the direct ML-ZnS band gap into indirect. Within our considered strain values of |δ| < 6%, the band gap shows linearly decreasing (non-linearly increasing as well as decreasing) variation with tensile (compressive) strain. These predictions (based on our calculations with two atoms per unit cell) may be exploited in future for potential applications in strain sensors and other nano-devices such as nano-electromechanical systems and nano-optomechanical systems. (paper)

  15. Multiphase nanodomains in a strained BaTiO3 film on a GdScO3 substrate

    Kobayashi, Shunsuke; Inoue, Kazutoshi; Kato, Takeharu; Ikuhara, Yuichi; Yamamoto, Takahisa

    2018-02-01

    Controlling the crystal structure of ferroelectric materials via epitaxial strain, which is a well-known technique in strain engineering, can lead to the formation of unique domain structures generating non-intrinsic phenomena such as electronic conductivity, photovoltages, and enhanced piezoelectric characteristics. Strained BaTiO3 films are promising ferroelectric materials as theoretical modeling predicts that different domain morphologies can introduce additional properties not observed in conventional BaTiO3 ceramics. To rationally design materials for practical application, a thorough understanding of the formation mechanisms and stabilities of different domain structures in strained BaTiO3 films is required. However, there have been very few experimental reports on this topic, and details about the domain structures in strained BaTiO3 films are currently lacking. In this paper, we report multiphase nanodomains in a strained BaTiO3 film deposited on an orthorhombic GdScO3 substrate. The phase-transition behavior of the strained BaTiO3 film reveals that it contains multiple phases at room temperature; the film first undergoes a phase-transition upon heating at around 550 K, and then a paraelectric phase forms at temperatures above 690 K. A picometer-scale analysis of the Ti ion displacements, using an advanced scanning transmission electron microscopy technique, is used to characterize the complex multiphase nanodomains, providing useful insights into the control of domain structures in BaTiO3 films by applying epitaxial strain.

  16. Large-strain time-temperature equivalence in high density polyethylene for prediction of extreme deformation and damage

    Gray G.T.

    2012-08-01

    Full Text Available Time-temperature equivalence is a widely recognized property of many time-dependent material systems, where there is a clear predictive link relating the deformation response at a nominal temperature and a high strain-rate to an equivalent response at a depressed temperature and nominal strain-rate. It has been found that high-density polyethylene (HDPE obeys a linear empirical formulation relating test temperature and strain-rate. This observation was extended to continuous stress-strain curves, such that material response measured in a load frame at large strains and low strain-rates (at depressed temperatures could be translated into a temperature-dependent response at high strain-rates and validated against Taylor impact results. Time-temperature equivalence was used in conjuction with jump-rate compression tests to investigate isothermal response at high strain-rate while exluding adiabatic heating. The validated constitutive response was then applied to the analysis of Dynamic-Tensile-Extrusion of HDPE, a tensile analog to Taylor impact developed at LANL. The Dyn-Ten-Ext test results and FEA found that HDPE deformed smoothly after exiting the die, and after substantial drawing appeared to undergo a pressure-dependent shear damage mechanism at intermediate velocities, while it fragmented at high velocities. Dynamic-Tensile-Extrusion, properly coupled with a validated constitutive model, can successfully probe extreme tensile deformation and damage of polymers.

  17. The Overall Response of Composite Materials Undergoing Large Deformations

    1992-10-15

    University, December 11, 1991. "Propiedades effectivas de materiales compuestos ." & "Propiedades effectivas de materiales compuestos no-lineales...uncoupled. As we will see in the ensuing discussions, this inter -mode coupling is one of the intrinsic features of laminated (and other anisotropic...3 15 fir -0.5 M3 0- 10 0 o0 2 3 4 5 Fig. 3. The inter -relations between the shear stress f and the longitudinal shear strain ,, of the

  18. The HRQoL of Chinese patients undergoing haemodialysis.

    Yu, Hui-Dan; Petrini, Marcia A

    2010-03-01

    With the transition from infectious disease and acute illness to chronic disease and degenerative illness as leading causes of death, health-related quality of life has become an important aspect in assessing the burden of chronic disease. The quality of life of haemodialysis patients has been studied extensively; however, very limited research using exploratory descriptive design has been carried out in this area in China. The aim of this study was to explore health-related quality of life of end-stage renal disease patients undergoing haemodialysis in China. This study used the qualitative research design approach. A semi-structured, in-depth interview was conducted with 16 haemodialysis patients in two hospitals using Colaizzi's phenomenological method to transcribe and analyse the data. The results of this study showed that dialysis patients show improvement in physical competence, but they also experienced emotional instability and psychological distress, financial burdens, inadequate disease knowledge and less social support which influenced their quality of life. To optimise the patients undergoing dialysis health-related quality of life, support of psycho-social-economical aspects should be enhanced. Health care providers should give haemodialysis patients thorough health education, individualised psychological and emotional intervention and adequate social support to optimise health-related quality of life.

  19. TEMPERATURE STRUCTURE OF PROTOPLANETARY DISKS UNDERGOING LAYERED ACCRETION

    Lesniak, M. V.; Desch, S. J.

    2011-01-01

    We calculate the temperature structures of protoplanetary disks (PPDs) around T Tauri stars heated by both incident starlight and viscous dissipation. We present a new algorithm for calculating the temperatures in disks in hydrostatic and radiative equilibrium, based on Rybicki's method for iteratively calculating the vertical temperature structure within an annulus. At each iteration, the method solves for the temperature at all locations simultaneously, and converges rapidly even at high (>>10 4 ) optical depth. The method retains the full frequency dependence of the radiation field. We use this algorithm to study for the first time disks evolving via the magnetorotational instability. Because PPD midplanes are weakly ionized, this instability operates preferentially in their surface layers, and disks will undergo layered accretion. We find that the midplane temperatures T mid are strongly affected by the column density Σ a of the active layers, even for fixed mass accretion rate M-dot . Models assuming uniform accretion predict midplane temperatures in the terrestrial planet forming region several x 10 2 K higher than our layered accretion models do. For M-dot -7 M sun yr -1 and the column densities Σ a -2 associated with layered accretion, disk temperatures are indistinguishable from those of a passively heated disk. We find emergent spectra are insensitive to Σ a , making it difficult to observationally identify disks undergoing layered versus uniform accretion.

  20. Unemployment risk among individuals undergoing medical treatment for chronic diseases.

    Nakaya, N; Nakamura, T; Tsuchiya, N; Tsuji, I; Hozawa, A; Tomita, H

    2016-03-01

    Chronic diseases increase the risk of unemployment even in non-disaster settings; therefore, in post-disaster settings, special attention needs to be paid to the employment status of those suffering from chronic diseases. To examine the association between chronic disease and the risk of unemployment in a disaster area. This cross-sectional study was conducted in Shichigahama Town, Miyagi, north-eastern Japan, where had been severely inundated by the 2011 tsunami. Logistic regression analyses were used to evaluate the association between undergoing medical treatment for a combination of chronic diseases (stroke, cancer, myocardial infarction and angina) and unemployment risk. Confounders such as psychological distress and levels of daily life activity were considered. Among the 2588 individuals studied, there was a statistically significant association between undergoing medical treatment for chronic disease and the risk of unemployment [odds ratio (OR) = 1.7, 95% confidence interval (CI) 1.02-2.7, P unemployment risk was observed only in participants with a higher degree of psychological distress and/or poorer levels of daily life activity. © The Author 2015. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Dental calculus formation in children and adolescents undergoing hemodialysis.

    Martins, Carla; Siqueira, Walter Luiz; Oliveira, Elizabeth; Nicolau, José; Primo, Laura Guimarães

    2012-10-01

    This study aimed to determine whether dental calculus formation is really higher among patients with chronic kidney disease undergoing hemodialysis than among controls. Furthermore, the study evaluated correlations between dental calculus formation and dental plaque, variables that are related to renal disease and/or saliva composition. The Renal Group was composed of 30 patients undergoing hemodialysis, whereas the Healthy Group had 30 clinically healthy patients. Stimulated whole saliva and parotid saliva were collected. Salivary flow rate and calcium and phosphate concentrations were determined. In the Renal Group the saliva collection was carried out before and after a hemodialysis session. Patients from both groups received intraoral exams, oral hygiene instructions, and dental scaling. Three months later, the dental calculus was measured by the Volpe-Manhold method to determine the rate of dental calculus formation. The Renal Group presented a higher rate of dental calculus formation (p dental calculus formation and whole saliva flow rate in the Renal Group after a hemodialysis session (r = 0.44, p dental calculus was associated with phosphate concentration in whole saliva from the Renal Group (p dental calculus formation, probably due to salivary variables.

  2. Children Undergoing Radiotherapy: Swedish Parents’ Experiences and Suggestions for Improvement

    Mullaney, Tara; Nilsson, Kristina; Wickart-Johansson, Gun; Svärd, Anna-Maja; Nyholm, Tufve; Lindh, Jack; Lindh, Viveca

    2015-01-01

    Approximately 300 children, from 0 to 18 years old, are diagnosed with cancer in Sweden every year. Of these children, 80–90 of them undergo radiotherapy treatment for their cancer. Although radiotherapy is an encounter with advanced technology, few studies have investigated the child’s and the parent’s view of the procedure. As part of an ongoing multicenter study aimed to improve patient preparation and the care environment in pediatric radiotherapy, this article reports the findings from interviews with parents at baseline. The aim of the present study was twofold: to describe parents’ experience when their child undergoes radiotherapy treatment, and to report parents’ suggestions for improvements during radiotherapy for their children. Sixteen mothers and sixteen fathers of children between 2–16 years old with various cancer diagnoses were interviewed. Data were analyzed using content analysis. The findings showed that cancer and treatment turns people’s lives upside down, affecting the entire family. Further, the parents experience the child’s suffering and must cope with intense feelings. Radiotherapy treatment includes preparation by skilled and empathetic staff. The parents gradually find that they can deal with the process; and lastly, parents have suggestions for improvements during the radiotherapy treatment. An overarching theme emerged: that despair gradually turns to a sense of security, with a sustained focus on and close interaction with the child. In conclusion, an extreme burden was experienced around the start of radiotherapy, though parents gradually coped with the process. PMID:26509449

  3. Attention-deficit/hyperactivity disorder in children undergoing peritoneal dialysis.

    Yousefichaijan, Parsa; Sharafkhah, Mojtaba; Vazirian, Shams; Seyedzadeh, Abolhasan; Rafeie, Mohammad; Salehi, Bahman; Amiri, Mohammad; Ebrahimimonfared, Mohsen

    2015-03-01

    Attention-deficit/hyperactivity disorder (ADHD) is the most common childhood psychiatric disorder. This disorder is more prevalent in some chronic disease. The aim of this study was to investigate ADHD in children with end-stage renal disease (ESRD) undergoing continuous ambulatory peritoneal dialysis (CAPD) and to compare the results with those of healthy children. This case-control study was conducted for six months (December 22, 2013 to June 21, 2014) on five to 16-year-old children, visiting the Pediatric Dialysis Unit of Amirkabir Hospital, Arak, Iran, and Taleghani Hospital, Kermanshah, Iran. A total of 100 children with ESRD who had undergone CAPD for at least six months and 100 healthy children were included in this study as case and control groups, respectively. ADHD was diagnosed by Conner's Parent Rating Scale-48 (CPRS-48) and DSM-IV-TR criteria, and was confirmed through consultation by psychologist. Data were analyzed by Binomial test in SPSS 18. The ADHD inattentive type was observed in 16 cases (16%) with CAPD and five controls (5%) (P = 0.01). Moreover, ADHD hyperactive-impulsive type was observed in 27 cases (27%) with CAPD and seven controls (9%) (P = 0.002). Despite these significant differences, no children were diagnosed with ADHD combined type among all subjects. Inattentive type and hyperactive-impulsive type of ADHD are more prevalent in children with ESRD undergoing CAPD. Therefore screening methods for ADHD is necessary in these patients.

  4. Pulmonary hypertenstion ad leading factor in patients undergoing dialysis

    Rehman, I.U.; Sumera, A.; Idrees, M.K.; Tanweer, A.

    2014-01-01

    Objective: To determine the frequency and leading factors of pulmonary hypertension among chronic hemodialysis patients. Study Design: Case series. Place and Duration of Study: Hemodialysis Unit, Department of Nephrology, Sindh Institute of Urology and Transplantation, Karachi, from September 2011 to March 2012. Methodology: Patients of either gender aged between 16 to 60 years of age undergoing hemodialysis for at least 3 months not having pre-existing valvular heart disease, chronic lung disease or connective tissue disorder were included. Pulmonary hypertension was prospectively estimated by Doppler echocardiogram on patients undergoing dialysis. Pulmonary artery pressure was calculated on the post-dialysis day and leading factors were compared between patients with and without pulmonary hypertension. Results: A total of 178 patients were included in study with male to female ratio120/58 (2.06:1). The mean age was 33.84 +- 11.9 years. The mean duration of hemodialysis was 23.85 +- 22.48 months. Pulmonary hypertension was found in 76 (42.7%) patients. Out of the studied factors, low serum albumin ( 3.4 mg/dl, p = 0.01) was found to be statistically significant in patients with pulmonary hypertension. Conclusion: Pulmonary hypertension was frequently present in dialysis population (42.7%). This subset of patients had significantly lower albumin levels in serum. More research is needed in its pathogenesis to arrest its course. (author)

  5. PSYCHOSOCIAL MORBIDITY IN PATIENTS UNDERGOING MASTECTOMY FOR BREAST CANCER

    Kavitha Konnakkaparambil Ramakrishnan

    2018-02-01

    Full Text Available BACKGROUND Breast Cancer is the most common female cancer worldwide and carries significant psychosocial morbidity. The diagnosis of the disease and the treatment modalities like surgery and chemotherapy contribute to the morbidity. The recognition of the psychosocial morbidity associated with mastectomy can help us formulate effective counselling strategies. The objectives of this study were- to assess the psychosocial morbidity in patients undergoing mastectomy for carcinoma breast, to identify the preoperative variables that predict the morbidity and to find out the correlation between degree of neuroticism of the individual and morbidity. MATERIALS AND METHODS 35 female patients who had mastectomy for breast cancer were evaluated at three time-points, preoperatively, immediately after surgery and 2 months after surgery. Anxiety and depression was assessed using Hospital Anxiety and Depression Scale (HADS, psychological distress was measured using General Health Questionnaire (GHQ-12 and neuroticism was assessed by Eysenck Personality Inventory Neuroticism subscale (EPI-N. RESULTS There was a high level of anxiety, depression and GHQ scores preoperatively with a further worsening of these over the three interviews. Age, marital status and menopausal status were factors which had an influence on psychosocial morbidity. Preoperative EPI-N scores positively correlated with psychosocial morbidity. CONCLUSION There is a high level of psychosocial morbidity in patients undergoing mastectomy for breast cancer and mastectomy seems to worsen it in the first two months after surgery. Our study shows that psychosocial morbidity is affected by age, marital status, menopausal status and level of neuroticism.

  6. Dental Health of Patients Undergoing Hemodialysis (A Study

    Vinay Mohan

    2011-01-01

    Full Text Available The primary purpose of this study was to determine the oral manifestations of patients undergoing dialysis. Two subgroups of the population were studied: (1 Those who have been on dialysis for less than one year, (2 those who have been on dialysis for more than one year. Two dental indices–periodontal index and decayed, missing, filled index were used to identify periodontal status, dental canes activity. Data were compiled and analyzed by using the unpaired t-test. Results suggested that 100% (n = 26 of the patients undergoing dialysis presented with some form of periodontal disease (mean value = 2.24, standard deviation = 1.33. Majority of the patients displayed either established periodontal disease (57.6% or the beginning of periodontal disease (38 4%. Approximately, 70% of the patients had high decayed, missing, filled index (mean value = 6.19, standard deviation = 6.40. Findings led to the conclusion that patients on dialysis need comprehensive professional oral care and self-care instructions. The source of infection in oral cavity can cause variety of systemic diseases, causing morbidity and mortality in these immune-suppressed patients.

  7. Management of Patients with Orthopaedic Implants Undergoing Dental Procedures.

    Quinn, Robert H; Murray, Jayson N; Pezold, Ryan; Sevarino, Kaitlyn S

    2017-07-01

    The American Academy of Orthopaedic Surgeons, in collaboration with the American Dental Association, has developed Appropriate Use Criteria (AUC) for the Management of Patients with Orthopaedic Implants Undergoing Dental Procedures. Evidence-based information, in conjunction with the clinical expertise of physicians, was used to develop the criteria to improve patient care and obtain best outcomes while considering the subtleties and distinctions necessary in making clinical decisions. The Management of Patients with Orthopaedic Implants Undergoing Dental Procedures AUC clinical patient scenarios were derived from indications of patients with orthopaedic implants presenting for dental procedures, as well as from current evidence-based clinical practice guidelines and supporting literature to identify the appropriateness of the use of prophylactic antibiotics. The 64 patient scenarios and 1 treatment were developed by the writing panel, a group of clinicians who are specialists in this AUC topic. Next, a separate, multidisciplinary, voting panel (made up of specialists and nonspecialists) rated the appropriateness of treatment of each patient scenario using a 9-point scale to designate a treatment as Appropriate (median rating, 7 to 9), May Be Appropriate (median rating, 4 to 6), or Rarely Appropriate (median rating, 1 to 3).

  8. Cerebroprotective effect of piracetam in patients undergoing coronary bypass burgery.

    Holinski, Sebastian; Claus, Benjamin; Alaaraj, Nour; Dohmen, Pascal Maria; Kirilova, Kremena; Neumann, Konrad; Uebelhack, Ralf; Konertz, Wolfgang

    2008-11-01

    Reduction of cognitive function is a possible side effect after cardiac surgery using cardiopulmonary bypass. We investigated the cerebroprotective effect of piracetam on cognitive performance in patients undergoing coronary artery bypass surgery under cardiopulmonary bypass. Patients scheduled for elective, primary and isolated coronary bypass surgery were randomised either to piracetam or placebo group. The study was performed in a double blind fashion. Patients received either 12 g piracetam or placebo at the beginning of the operation. Six neuropsychological subtests from the Syndrom Kurz Test and the Alzheimer's Disease Assessment Scale were performed preoperatively and on the third postoperative day. To assess the overall cognitive function and the degree of cognitive decline across all tests after surgery we combined the six test-scores by principal component analysis. A total number of 120 patients were enrolled into the study. Preoperative overall cognitive function were not significantly different between the groups. The postoperative combined score of the neuropsychological tests showed a deterioration of cognitive function in both groups (placebo-pre: -0.06+/-0.99 vs placebo-post: -1.38+/-1.11; ppiracetam-pre: 0.06+/-1.02 vs piracetam-post: -0.65+/-0.93; ppiracetam patients performed significantly better compared to the placebo patients after the operation and had a less decline of overall cognitive function (pPiracetam has a cerebroprotective effect in patients undergoing coronary artery bypass surgery with the use of cardiopulmonary bypass. It reduces an early postoperative substantial decline of neuropsychological abilities.

  9. Managing direct oral anticoagulants in patients undergoing dentoalveolar surgery.

    Patel, J P; Woolcombe, S A; Patel, R K; Obisesan, O; Roberts, L N; Bryant, C; Arya, R

    2017-02-24

    Our objective was to describe our experience of managing a cohort of adult patients prescribed direct oral anticoagulants (DOACs) undergoing dentoalveolar procedures between November 2012 and May 2016. Prior to conducting a procedure a formal assessment was made of each patient's anticoagulation treatment. A specific plan was then formulated, balancing the risk of bleeding with the risk of thrombosis. Patients received a telephone consultation one week following treatment to assess any post-operative bleeding. Eighty-two patients underwent 111 oral surgical procedures, the majority of which were dental extractions. In the case of 35 (32%) procedures, advice was given to omit the DOAC, either before or after treatment. There was no bleeding following the majority of procedures. Persistent bleeding followed 15 (13.5%) procedures, of which 7 (6.3%) procedures required specific intervention. The majority of patients prescribed DOACs can undergo dentoalveolar procedures safely. Important considerations when planning treatment are: (i) when the patient usually takes their dose of DOAC, (ii) the time the procedure is performed and, (iii) when the DOAC is taken post-procedure. In our experience, if these factors are considered carefully, omission of DOAC doses is unlikely to be required for most patients.

  10. Effect of internet on Chinese patients undergoing elective laparoscopic cholecystectomy.

    Xu, Xiequn; Hong, Tao; Li, Binglu; Liu, Wei

    2015-04-01

    It is a growing trend that patients seek health information on the internet to self-educate and self-diagnose, which impacts their health decisions. The aim of the study was to investigate how Chinese patients undergoing elective laparoscopic cholecystectomy (LC) sought information about their disease and treatment, how they preferred the information to be presented, and how it influenced them. A descriptive, cross-sectional-designed questionnaire was employed to obtain information from 248 Chinese patients undergoing elective LC in Peking Union Medical College Hospital. A total of 223 patients (89.9 %) sought health information from the internet. Patients searching the internet for information about LC were younger than those who did not. It varied with employment status, educational level, and household average income. Among patients searching the internet for LC information, 35.4 % felt more worried and 37.2 % felt more assured; 15.2 % went to visit other doctors and 8.5 % considered changing their treatment because of internet use. A significant proportion of patients used the internet to obtain information about their disease. Age, employment status, educational level, and household average monthly income had an effect on internet usage for LC information. The use of the internet could cause mixed emotional outcomes among patients. Physicians should guide Chinese patients to professional websites of high quality and take time to discuss the information with patients during their visits and consultations.

  11. Fospropofol Disodium for Sedation in Elderly Patients Undergoing Flexible Bronchoscopy.

    Silvestri, Gerard A; Vincent, Brad D; Wahidi, Momen M

    2011-01-01

    BACKGROUND: Fospropofol disodium is a water-soluble prodrug of propofol. A subset analysis was undertaken of elderly patients (≥65 y) undergoing flexible bronchoscopy, who were part of a larger multicenter, randomized, double-blind study. METHODS: Patients received fentanyl citrate (50 mcg) followed by fospropofol at initial (4.88mg/kg) and supplemental (1.63mg/kg) doses. The primary end point was sedation success (3 consecutive Modified Observer's Assessment of Alertness/Sedation scores of ≤4 and procedure completion without alternative sedative or assisted ventilation). Treatment success, time to fully alert, patient and physician satisfaction, and safety/tolerability were also evaluated. RESULTS: In the elderly patients subset (n=61), sedation success was 92%, the mean time to fully alert was 8.0±10.9 min, and memory retention was 72% during recovery, and these were comparable with the younger patients subgroup (age, Sedation-related adverse events occurred in 23% of the elderly and 18% of the younger patients (age, sedation, rapid time to fully alert, and high satisfaction in this elderly subset undergoing flexible bronchoscopy, which was comparable with outcomes in younger patients.

  12. Haemophilus ducreyi Cutaneous Ulcer Strains Are Nearly Identical to Class I Genital Ulcer Strains.

    Dharanesh Gangaiah

    Full Text Available Although cutaneous ulcers (CU in the tropics is frequently attributed to Treponema pallidum subspecies pertenue, the causative agent of yaws, Haemophilus ducreyi has emerged as a major cause of CU in yaws-endemic regions of the South Pacific islands and Africa. H. ducreyi is generally susceptible to macrolides, but CU strains persist after mass drug administration of azithromycin for yaws or trachoma. H. ducreyi also causes genital ulcers (GU and was thought to be exclusively transmitted by microabrasions that occur during sex. In human volunteers, the GU strain 35000HP does not infect intact skin; wounds are required to initiate infection. These data led to several questions: Are CU strains a new variant of H. ducreyi or did they evolve from GU strains? Do CU strains contain additional genes that could allow them to infect intact skin? Are CU strains susceptible to azithromycin?To address these questions, we performed whole-genome sequencing and antibiotic susceptibility testing of 5 CU strains obtained from Samoa and Vanuatu and 9 archived class I and class II GU strains. Except for single nucleotide polymorphisms, the CU strains were genetically almost identical to the class I strain 35000HP and had no additional genetic content. Phylogenetic analysis showed that class I and class II strains formed two separate clusters and CU strains evolved from class I strains. Class I strains diverged from class II strains ~1.95 million years ago (mya and CU strains diverged from the class I strain 35000HP ~0.18 mya. CU and GU strains evolved under similar selection pressures. Like 35000HP, the CU strains were highly susceptible to antibiotics, including azithromycin.These data suggest that CU strains are derivatives of class I strains that were not recognized until recently. These findings require confirmation by analysis of CU strains from other regions.

  13. Engineering piezoresistivity using biaxially strained silicon

    Pedersen, Jesper Goor; Richter, Jacob; Brandbyge, Mads

    2008-01-01

    of the piezocoefficient on temperature and dopant density is altered qualitatively for strained silicon. In particular, we find that a vanishing temperature coefficient may result for silicon with grown-in biaxial tensile strain. These results suggest that strained silicon may be used to engineer the iezoresistivity...

  14. drug resistant strains of Salmonella enterica

    Conclusions: The aqueous extract of Thonningia sanguinea can provide an alternative therapy for the treatment of salmonellosis, mainly for typhoid fever caused by MDR strains of S. Typhi.The extract also inhibits S.Hadar a MDR emerging strain in Ivory Coast. Keywords: Thonningia sanguinea; Salmonella, MDR strains, ...

  15. Development of high temperature strain gage, (5)

    Yuuki, Hiroshi; Kobayashi, Yukio; Kanai, Kenji; Yamaura, Yoshio

    1976-01-01

    Development and improvement of resistance wire type strain gages usable for experimental measurement of thermal strains generated at high temperature in various structures and equipments that consist of a Fast Breeder Reactor have been carried out, and various characteristics of the strain gages have been investigated. Based on the results obtained up to now, development and research of this time mainly aim to improve strain and fatigue characteristics. As the results, characteristics of strain gages with sensing elements of nichrome V are improved, specifically mechanical hysteresis is decreased, strain limit is increased, etc. Also, improvement is recognized in thermal output, and it becomes clear that dummy gages work effectively. However, a filling method of MgO and an inserting method of active-dummy elements are selected as primary objects to improve strain characteristics, and many hours are taken for these objects, so confirmations of characteristics of platinum-tungsten strain gages, strain sensing elements of which are troublesome to produce, have not been completely done, though the performance of the gages has been improved in several points. As to nichrome V strain gages, there is a fair prospect of obtaining ones, specifications of which are quite close to the goal, though problems in manufacturing technics remain for future. As to platinum-tungsten strain gages, it is expected that similar strain gages to nichrome V are obtainable by improvement in manufacturing of sensing elements. (auth.)

  16. Strain path dependency in metal plasticity

    Viatkina, E.M.; Brekelmans, W.A.M.; Geers, M.G.D.

    2003-01-01

    A change in strain path has a significant effect on the mechanical response of metals. Strain path change effects physically originate from a complex microstructure evolution. This paper deals with the contribution of cell structure evolution to the strain path change effect. The material with cells

  17. Stress and strain measurements in solids

    Askegaard, V.

    1978-01-01

    A design basis is given for stress- and strain cells to be used in a solid either externally loaded or with a stressfree strain field (for example shrinkage). A stress- and a strain cell has been designed for use in granular materials. Calibration tests show either good or reasonably good correspondance with calculated values. (orig.) [de

  18. Spontaneous abortion and physical strain around implantation

    Hjollund, N H; Jensen, Tina Kold; Bonde, Jens Peter

    2000-01-01

    pregnancy the women recorded physical strain prospectively in a structured diary. Physical strain around the time of implantation was associated with later spontaneous abortion. The adjusted risk ratio for women who reported physical strain higher than average at day 6 to 9 after the estimated date...

  19. Strain engineering of van der Waals heterostructures

    Vermeulen, Paul A.; Mulder, Jefta; Momand, Jamo; Kooi, Bart J.

    2018-01-01

    Modifying the strain state of solids allows control over a plethora of functional properties. The weak interlayer bonding in van der Waals (vdWaals) materials such as graphene, hBN, MoS2, and Bi2Te3 might seem to exclude strain engineering, since strain would immediately relax at the vdWaals

  20. Financial strain and smoking cessation among men and women within a self-guided quit attempt.

    Reitzel, Lorraine R; Langdon, Kirsten J; Nguyen, Nga T; Zvolensky, Michael J

    2015-08-01

    Financial strain, defined as an unfavorable asset-to-needs ratio, has been associated with reduced odds of smoking cessation in the context of a structured clinical study providing cessation assistance. This study reports on a secondary data analysis that assessed the association of financial strain and biochemically-verified smoking abstinence within a structured clinical study of smokers making a self-guided cessation attempt. Participants (N=58; 65.5% men) were enrolled in a study about anxiety sensitivity and smoking cessation whereby they were instructed to initiate a self-guided quit attempt. Relations between financial strain and biochemically-verified smoking abstinence on the quit day and at Days 3, 7, 14, 28, and 90 post-quit were assessed using generalized estimating equations controlling for age, sex, race, education, partner status, pre-quit cigarettes smoked per day, and time. Associations between financial strain and abstinence in the whole sample were marginal (aOR=.94, 95% CI=.87-1.01, observations=293; p=.07). However, sex was a significant moderator: greater financial strain was associated with lower odds of abstinence for men (aOR=.90, 95% CI=.80-1.00, observations=201; p=.05), but not women (aOR=1.05, 95% CI=.91-1.21, observations=92; p=.48). Results indicated that financial strain was associated with lower odds of cessation among men undergoing a self-guided quit attempt in the context of a structured clinical study. These data suggest that financial strain may be an important socioeconomic determinant of smoking cessation and support its relevance for better understanding socioeconomic-based smoking-related health disparities. Future work may benefit by exploring sex-specific models of financial strain in the context of smoking cessation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Temperature dependence of microstructure and strain evolution in strained ZnO films on Al2O3(0001)

    Kim, In-Woo; Lee, Kyu-Mann

    2008-01-01

    We have studied the temperature dependence of the growth mode and microstructure evolution in highly mismatched sputter-grown ZnO/Al 2 O 3 (0001) heteroepitaxial films. The growth mode was studied by real-time synchrotron x-ray scattering. We find that the growth mode changes from a two-dimensional (2D) layer to a 3D island in the early growth stage with temperature (300-600 deg. C), in sharp contrast to the reported transition from three dimensions to two dimensions in metal-organic vapor phase epitaxy. At around 400 deg. C intermediate 2D platelets nucleate in the early stage, which act as nucleation cores of 3D islands and transform to a misaligned state during further growth. Meanwhile, at high temperature (above 500 deg. C), the spinel structure of ZnAl 2 O 4 grows in the early stage, and it undergoes a transition to wurtzite-ZnO (w-ZnO) with thickness. The spinel formation is presumably driven by high temperature and large incident energy of impacting atoms during sputtering. The results of the strain evolution as functions of temperature and thickness during growth suggest that the surface diffusion is a major factor determining the microstructural properties in the strained ZnO/Al 2 O 3 (0001) heteroepitaxy

  2. On lower order strain gradient plasticity theories

    Niordson, Christian Frithiof; Hutchinson, J. W.

    2003-01-01

    By way of numerical examples, this paper explores the nature of solutions to a class of strain gradient plasticity theories that employ conventional stresses, equilibrium equations and boundary conditions. Strain gradients come into play in these modified conventional theories only to alter...... the tangent moduli governing increments of stress and strain. It is shown that the modification is far from benign from a mathematical standpoint, changing the qualitative character of solutions and leading to a new type of localization that is at odds with what is expected from a strain gradient theory....... The findings raise questions about the physical acceptability of this class of strain gradient theories....

  3. Spontaneous abortion and physical strain around implantation

    Hjøllund, Niels Henrik Ingvar; Jensen, T.K.; Bonde, J.P.

    2000-01-01

    Existing studies of physical strain and spontaneous abortion are mainly retrospective or based only on pregnancies that have survived the first trimester. Furthermore, almost all studies have relied on averaged measures of physical strain, which tend to blur an effect if peak values during short...... pregnancy the women recorded physical strain prospectively in a structured diary. Physical strain around the time of implantation was associated with later spontaneous abortion. The adjusted risk ratio for women who reported physical strain higher than average at day 6 to 9 after the estimated date...

  4. Local strains in waste tank deflagration analysis

    Bryan, B.J.; Flanders, H.E. Jr.

    1993-01-01

    In recent years extensive effort has been expended to qualify buried nuclear waste storage tanks under accident conditions. One of these conditions is deflagration of the combustible gases which may build up over time. While much work has been done to calculate the general strain state, less effort has been made to address the local strains at structural discontinuities. An analytical method is presented for calculating these local strains and combining them with the general strain state. A closed form solution of the local strains is compared to a finite element solution

  5. Sensibility of different wheat varieties (strains) to Ar+ implantation

    Cui Huanhu; Jing Hua; Ma Aiping; Kang Xiuli; Yang Liping; Huang Mingjing; Ma Buzhou; Shanxi Academy of Agricultural Sciences, Taiyuan

    2005-01-01

    The sensibility of different wheat varieties (strains) to Ar + implantation was studied. The results showed that the survival rate of 21 wheat varieties (strains) at the dose of 6 x 10 16 Ar + /cm 2 could be divided into five groups: surplus sensitive varieties (strains), sensitive varieties (strains), transitional varieties (strains), obtuse varieties (strains) and surplus obtuse varieties (strains). The sensibility of wheat varieties (strains) to Ar + injection is high-moisture-fertility wheat varieties (strains) > medium-moisture-fertility wheat varieties (strains) > dry land wheat varieties (strains). The study has provided theoretical basis in induced mutation medial lethal dose of different wheat varieties (strains) to Ar + implantation. (authors)

  6. Stress-strain properties of railway steel at strain rates of upto 105 per second

    Hashmi, M.S.J.; Islam, M.N.

    1985-01-01

    This paper presents the stress-strain characteristics of railway steel at strain rates of up to 10 5 /s at room temperature determined by a new technique. In determining the results, account has been taken of the strain-rate variation, the total strain and the strain rate history. The effect of friction, material inertia and temperature rise is also assessed and an empirical constitutive equation describing the strain-rate and strain sensitive flow stress for this type of steel is proposed. (orig.)

  7. Nasogastric intubation causes gastroesophageal reflux in patients undergoing elective laparotomy.

    Manning, B J

    2012-02-03

    BACKGROUND: The routine use of nasogastric tubes in patients undergoing elective abdominal operation is associated with an increased incidence of postoperative fever, atelectasis, and pneumonia. Previous studies have shown that nasogastric tubes have no significant effect on the incidence of gastroesophageal reflux or on lower esophageal sphincter pressure in healthy volunteers. We hypothesized that nasogastric intubation in patients undergoing laparotomy reduces lower esophageal sphincter pressure and promotes gastroesophageal reflux in the perioperative period. METHODS: A prospective randomized case-control study was undertaken in which 15 consenting patients, admitted electively for bowel surgery, were randomized into 2 groups. Group 1 underwent nasogastric intubation after induction of anesthesia, and Group 2 did not. All patients had manometry and pH probes placed with the aid of endoscopic vision at the lower esophageal sphincter and distal esophagus, respectively. Nasogastric tubes, where present, were left on free drainage, and sphincter pressures and pH were recorded continuously during a 24-hour period. Data were analyzed with 1-way analysis of variance. RESULTS: The mean number of reflux episodes (defined as pH < 4) in the nasogastric tube group was 137 compared with a median of 8 episodes in the group managed without nasogastric tubes (P =.006). The median duration of the longest episode of reflux was 132 minutes in Group 1 and 1 minute in Group 2 (P =.001). A mean of 13.3 episodes of reflux lasted longer than 5 minutes in Group 1, with pH less than 4 for 37.4% of the 24 hours. This was in contrast to Group 2 where a mean of 0.13 episodes lasted longer than 5 minutes (P =.001) and pH less than 4 for 0.2% of total time (P =.001). The mean lower esophageal sphincter pressures were lower in Group 1. CONCLUSIONS. These findings demonstrate that patients undergoing elective laparotomy with routine nasogastric tube placement have significant gastroesophageal

  8. Strain quantification in epitaxial thin films

    Cushley, M

    2008-01-01

    Strain arising in epitaxial thin films can be beneficial in some cases but devastating in others. By altering the lattice parameters, strain may give a thin film properties hitherto unseen in the bulk material. On the other hand, heavily strained systems are prone to develop lattice defects in order to relieve the strain, which can cause device failure or, at least, a decrease in functionality. Using convergent beam electron diffraction (CBED) and high-resolution transmission electron microscopy (HRTEM), it is possible to determine local strains within a material. By comparing the results from CBED and HRTEM experiments, it is possible to gain a complete view of a material, including the strain and any lattice defects present. As well as looking at how the two experimental techniques differ from each other, I will also look at how results from different image analysis algorithms compare. Strain in Si/SiGe samples and BST/SRO/MgO capacitor structures will be discussed.

  9. Sexuality in gynecological patients undergoing radiation therapy treatments

    Dolan, M.E.

    1987-01-01

    The gynecology patient undergoing radiation therapy treatments may experience physiological and psychological problems related to sexuality. The needs of this group must be met by the radiation oncology staff by their being informed, interested, and experienced in dealing with sexual problems created by radiation therapy treatments. Opportunities to obtain information and for discussion about how the disease and its treatments will affect sexual functioning must be provided for the patient and partner. It is important to remember that the ability to seek and preserve gratifying sexual function is of great importance to almost all women, regardless of age. The patient may feel much personal distress related to the disease, the treatments, and how they affect the way she feels as a sexual human being. Opportunities must be provided to share the feelings created by the treatment process and trained therapists should be available when intensive sexual counseling is needed

  10. Opportunistic microorganisms in patients undergoing antibiotic therapy for pulmonary tuberculosis

    Silvia Maria Rodrigues Querido

    2011-12-01

    Full Text Available Antimicrobial therapy may cause changes in the resident oral microbiota, with the increase of opportunistic pathogens. The aim of this study was to compare the prevalence of Candida, Staphylococcus, Pseudomonas and Enterobacteriaceae in the oral cavity of fifty patients undergoing antibiotic therapy for pulmonary tuberculosis and systemically healthy controls. Oral rinsing and subgingival samples were obtained, plated in Sabouraud dextrose agar with chloramphenicol, mannitol agar and MacConkey agar, and incubated for 48 h at 37ºC. Candida spp. and coagulase-positive staphylococci were identified by phenotypic tests, C. dubliniensis, by multiplex PCR, and coagulase-negative staphylococci, Enterobacteriaceae and Pseudomonas spp., by the API systems. The number of Candida spp. was significantly higher in tuberculosis patients, and C. albicans was the most prevalent specie. No significant differences in the prevalence of other microorganisms were observed. In conclusion, the antimicrobial therapy for pulmonary tuberculosis induced significant increase only in the amounts of Candida spp.

  11. Should violent offenders be forced to undergo neurotechnological treatment?

    Petersen, Thomas Søbirk; Kragh, Kristian

    2017-01-01

    ’s right to freedom of thought. We argue that this objection can be challenged. First, we present some specifications of what a right to freedom of thought might mean. We focus on the recently published views of Jared Craig, and Jan Cristopher Bublitz and Reinhard Merkel. Secondly, we argue that forcing...... violent offenders to undergo certain kinds of NT may not violate the offender’s right to freedom of thought as that right is specified by Craig, and Bublitz and Merkel. Thirdly, even if non-consensual NT is used in a way that does violate freedom of thought, such use can be difficult to abandon without...... inconsistency. For if one is not an abolitionist, and therefore accepts traditional state punishments for violent offenders like imprisonment – which, the evidence shows, often violate the offender’s right to freedom of thought – then, it is argued, one will have reason to accept that violent offenders can...

  12. Study of alloy crystallization in systems undergoing peritectic transformations

    Psarev, V.I.; Kirij, V.G.; Kuznetsov, A.V.; Psareva, I.V.; Ivanov, A.L.

    1982-01-01

    Studies into Ge-Te, In-Te, Al-Mn, Sb-Zn, Sn-Au systems are carried out at melt cooling rates from 50 deg/h to 10 5 deg/h to establish regularities in stable and metastable crystallization of alloys undergoing peritectic transformations. Methods of metallographic, X-ray phase and X-ray diffraction analyses are used. Differentiation in types of peritectic transformations is made through their mechanisms under equilibrium and non-equilibrium crystallization conditions for various alloy systems. It is found out that ability to supercooling even at low or moderate cooling rates for Te-Ge and Te-In system melts can be one of the main indication of the possibility of amorphous alloy formation [ru

  13. WHO HAS TO UNDERGO CANCER GENETIC TESTING? A PERSPECTIVE.

    Carmen Rinaldi

    2017-10-01

    Full Text Available Genetic testing is a medical tool employed to screen changes in genes linked to cancer and other genetic diseases. Genetic tests are available for breast, ovarian, colon, thyroid, and some other cancers and they represent the main tool for early identification of the “risk” subjects. The choice to undergo genetic testing by a healthy or affected cancer patient with family history of the cancer has to be the fruit of a careful and prudent assessment of the advantages and disadvantages discussed during oncogenetic counselling. The latter, in turn, in the case of a patient's positive and informed choice, must constantly affiliate the genetic testing, in order to preserve the prediction and information role of the test as much as possible.

  14. Quantifying risk of transfusion in children undergoing spine surgery.

    Vitale, Michael G; Levy, Douglas E; Park, Maxwell C; Choi, Hyunok; Choe, Julie C; Roye, David P

    2002-01-01

    The risks and costs of transfusion are a great concern in the area of pediatric spine surgery, because it is a blood-intensive procedure with a high risk for transfusion. Therefore, determining the predictors of transfusion in this patient population is an important first step and has the potential to improve upon the current approaches to reducing transfusion rates. In this study, we reveal several predictors of transfusion in a pediatric patient population undergoing spine surgery. In turn, we present a general rule of thumb ("rule of two's") for gauging transfusion risk, thus enhancing the surgeon's approach to avoiding transfusion in certain clinical scenarios. This study was conducted to determine the main factors of transfusion in a population of pediatric patients undergoing scoliosis surgery. The goal was to present an algorithm for quantifying the true risk of transfusion for various patient groups that would highlight patients "at high risk" for transfusion. This is especially important in light of the various risks associated with undergoing a transfusion, as well as the costs involved in maintaining and disposing of exogenous blood materials. This is a retrospective review of a group of children who underwent scoliosis surgery between 1988 and 1995 at an academic institution. A total of 290 patients were analyzed in this study, of which 63 were transfused and 227 were not. No outcomes measures were used in this study. A retrospective review of 290 patients presenting to our institution for scoliosis surgery was conducted, with a focus on socioclinical data related to transfusion risk. Univariate analysis and logistic regression were used to quantify the determinants of transfusion risk. Univariate analysis identified many factors that were associated with the risk of transfusion. However, it is clear that several of these factors are dependent on each other, obscuring the true issues driving transfusion need. We used multivariate analysis to control for

  15. Liquid discharges from patients undergoing {sup 131}I treatments

    Barquero, R. [Servicio de Radiofisica y Proteccion Radiologica, Hospital Universitario Rio Hortega, E-47010 Valladolid (Spain)], E-mail: rbarquero@hurh.sacyl.es; Basurto, F. [Departamento de Fisica Teorica, Atomica y Optica, Universidad de Valladolid, E-47010 Valladolid (Spain); Nunez, C. [Servicio de Radiofisica y Proteccion Radiologica, Fundacion Jimenez Diaz, FJD, E-82001 Madrid (Spain); Esteban, R. [Servicio de Radiologia, Hospital Clinico Universitario, E-47005 Valladolid (Spain)

    2008-10-15

    This work discusses the production and management of liquid radioactive wastes as excretas from patients undergoing therapy procedures with {sup 131}I radiopharmaceuticals in Spain. The activity in the sewage has been estimated with and without waste radioactive decay tanks. Two common therapy procedures have been considered, the thyroid cancer (4.14 GBq administered per treatment), and the hyperthyroidism (414 MBq administered per treatment). The calculations were based on measurements of external exposure around the 244 hyperthyroidism patients and 23 thyroid cancer patients. The estimated direct activity discharged to the sewage for two thyroid carcinomas and three hyperthyroidisms was 14.57 GBq and 1.27 GBq, respectively, per week; the annual doses received by the most exposed individual (sewage worker) were 164 {mu}Sv and 13 {mu}Sv, respectively. General equations to calculate the activity as a function of the number of patient treated each week were also obtained.

  16. Changes in preoperative characteristics in patients undergoing radical prostatectomy

    Røder, Martin Andreas; Brasso, Klaus; Christensen, Ib Jarle

    2014-01-01

    of a shift in attitude with increasing opportunistic PSA testing. This had led to an increasing number of RPs being performed in Denmark. The objective of this study was to analyze changes in preoperative characteristics over time for the complete cohort of 6489 men who underwent RP between 1995 and 2011....... Our hypothesis was that an increasing amount of men undergo RP for lower risk PCa. MATERIAL AND METHODS: All patients operated from 1995 to 2011 were identified via patient files and registries. Changes over time in age at surgery, preoperative PSA, clinical T-category, biopsy Gleason score (GS......, especially after 2005. Biopsy GS = 7 was found in 20.2% of the patients in 2005 compared to 57.1% in 2011. The proportion of T1 disease increased from 32% to 56%. Significant changes in percentage of patients according to the D'Amico classification were found. After 2005 the proportion of intermediate...

  17. Prevalence of Endometriosis Among Women Undergoing Laparoscopic Procedures

    K. K. Chu

    1995-01-01

    Full Text Available We evaluated 752 patients for endometriosis in consecutive laparoscopic procedures over a one year period. Six hundred eighty patients underwent laparoscopy for indications unrelated to symptoms of endometriosis and 72 patients were diagnosed clinically to have endometriosis before the procedures. In the 72 patients with clinical indications of endometriosis, 59 patients had disease confirmed at surgery (82%. Out of 680 asymptomatic patients, 186 patients (24.7% were documented to have the disease of various characteristics or appearances in which the typical lesions accounted for 42%. The overall prevalence among these women undergoing laparoscopy was 32.5%. However, a prevalence of 12% was shown in a subset of asymptomatic patients indicated for sterilization. This may reflect the appropriate prevalence in reproductive age population.

  18. Epidemiological evaluation of hepatic trauma victims undergoing surgery.

    Kalil, Mitre; Amaral, Isaac Massaud Amim

    2016-02-01

    to evaluate the epidemiological variables and diagnostic and therapeutic modalities related to hepatic trauma patients undergoing laparotomy in a public referral hospital in the metropolitan region of Vitória-ES. we conducted a retrospective study, reviewing charts of trauma patients with liver injuries, whether isolated or in association with other organs, who underwent exploratory laparotomy, from January 2011 to December 2013. We studied 392 patients, 107 of these with liver injury. The male: female ratio was 6.6 : 1 and the mean age was 30.12 years. Penetrating liver trauma occurred in 78.5% of patients, mostly with firearms. Associated injuries occurred in 86% of cases and intra-abdominal injuries were more common in penetrating trauma (p trauma was 60%, and penetrating trauma, 87.5% (p trauma remain high, especially in patients suffering from blunt trauma in relation to penetrating one.

  19. Frequency of renal artery stenosis in patients undergoing cardiac catheterization

    Lashari, M.N.; Ahmed, R.; Soomro, K.; Ishaq, M.

    2009-01-01

    Due to scarcity of local data regarding frequency of Renal Artery Stenosis (RAS), it is important to perform simultaneous renal arteriography in Patients undergoing coronary arterteriography for suspected coronary artery disease (CAD), in order to recognize all potential candidates for renal artery stenosis. It is cross sectional study. Three hundred patients, 157 male and 143 female with average age of 56+-8 Years and 55+-7 years respectively underwent simultaneous coronary and renal arteriography. Renal artery stenosis (RAS) was identified in 23.6% patients. Significant RAS (>50%) was present in 15% of patients. Hypertension, Dyslipidemia, smoking and diabetes mellitus were present in 88%, 80%, 50% and 49% respectively. Three vessel, two vessel and single vessel disease were seen in 58 %, 36% and 6% of patients. It is important to do simultaneous coronary and renal arteriography especially in patient having multiple risk factors and multi vessel coronary artery disease. (author)

  20. Frequency of renal artery stenosis in patients undergoing cardiac catheterization

    Lashari, M N; Ahmed, R; Soomro, K; Ishaq, M [Civil Hospital, Karachi (Pakistan)

    2009-07-15

    Due to scarcity of local data regarding frequency of Renal Artery Stenosis (RAS), it is important to perform simultaneous renal arteriography in Patients undergoing coronary arterteriography for suspected coronary artery disease (CAD), in order to recognize all potential candidates for renal artery stenosis. It is cross sectional study. Three hundred patients, 157 male and 143 female with average age of 56+-8 Years and 55+-7 years respectively underwent simultaneous coronary and renal arteriography. Renal artery stenosis (RAS) was identified in 23.6% patients. Significant RAS (>50%) was present in 15% of patients. Hypertension, Dyslipidemia, smoking and diabetes mellitus were present in 88%, 80%, 50% and 49% respectively. Three vessel, two vessel and single vessel disease were seen in 58 %, 36% and 6% of patients. It is important to do simultaneous coronary and renal arteriography especially in patient having multiple risk factors and multi vessel coronary artery disease. (author)

  1. Quality of life of women undergoing treatment for cervical cancer

    Francieli Ana Dallabrida

    2014-04-01

    Full Text Available This study aimed to evaluate the quality of life of women with cervical cancer. This is a cross-sectional, descriptive study developed with 43 women undergoing oncological treatment assisted at an Oncology High Complexity Center, in the Southern region of Brazil. The instrument used was the European Organization for Research and Treatment of Cancer – Quality of Life Questionnaire Core-30, and the data were analyzed through descriptive statistics. The average age was 54.6 years old. Married women prevailed (53.4%, with incomplete elementary education (72.1% and income from one to two minimum wages (62.8%. Quality of Life was considered very satisfactory. According to the development scales and emotional functioning, the result was from regular to satisfactory. The most frequent symptoms were fatigue, lack of appetite and pain. There is a need of structure of public health policies, for preventing cervical cancer in the most vulnerable population.

  2. Studies on Drosophila radiosensitivity strains

    Varentsova, E.R.; Sharygin, V.I.; Khromykh, Yu.U.

    1985-01-01

    Fertility of radiosensitive mutant drosophila female strain rad (2) 201 61 after irradiation and frequency of dominant lethal mutations (DLM), induced by γ-radiation for 0-5 h and 5-7 days, are investigated. It is shown, that oocytes of the mutant strain are more radiosensitive as compared with cells of mongrel flies as to criterion of DLM appearance over the period of maturing. Early oocytes of stages 2-7 are the most sensitive, i.e. at the stages, corresponding to the manifestation of previously established recombination-defective properties of mutations rad (2) 201 61 . It is also sown, that doses of γ-rays, exceeding 10 Gy produce a strong sterilizing effect on mutant females due to destruction and resorption of egg chambers, irradiated at the stages of previtellogenetic growth of oocytes. In females, carrying mutation of radiosensitivity there is no direct correlation betwen sensitivity of oocytes proper to DLM induction and sensitivity of egg folleicles to resorbing effect of γ-rays. The ways of possible involvement of mutant locus studied into genetic processes in various specialized cells of drosophila

  3. Radiation dose rates from adult patients undergoing nuclear medicine investigations

    Mountford, P.J.; O'Doherty, M.J.; Forge, N.I.; Jeffries, A.; Coakley, A.J.

    1991-01-01

    Adult patients undergoing nuclear medicine investigations may subsequently come into close contact with members of the public and hospital staff. In order to expand the available dosimetry and derive appropriate recommendations, dose rates were measured at 0.1, 0.5 and 1.0 m from 80 adult patients just before they left the nuclear medicine department after undergoing one of eight 99 Tc m studies, an 123 I thyroid, an 111 In leucocyte or a 201 Tl cardiac scan. The maximum departure dose rates at these distances of 150, 30 and 7.3 μSv h -1 were greater than those found in similar published studies of adult and paediatric patients. To limit the dose to an infant to less than 1 mSv, an 111 In leucocyte scan is the only investigation for which it may be necessary to restrict close contact between the infant and a radioactive parent, depending on the dose rate near the surface of the patient, the parent's habits and how fretful is the infant. It is unlikely that a ward nurse will receive a dose of 60 μSv in a working day if caring for just one radioactive adult patient, unless the patient is classified as totally helpless and had undergone a 99 Tc m marrow, bone or brain scan. The data and revised calculations of effective exposure times based on a total close contact time of 9 h in every 24 h period should allow worst case estimates of radiation dose to be made and recommendations to be formulated for other circumstances, including any future legislative changes in dose limits or derived levels. (author)

  4. The significance of peripartum fever in women undergoing vaginal deliveries.

    Bensal, Adi; Weintraub, Adi Y; Levy, Amalia; Holcberg, Gershon; Sheiner, Eyal

    2008-10-01

    We investigated whether patients undergoing vaginal delivery who developed peripartum fever (PPF) had increased rates of other gestational complications. A retrospective study was undertaken comparing pregnancy complications of patients who developed PPF with those who did not. A multivariable logistic regression model was constructed to control for confounders. To avoid ascertainment bias, the year of birth was included in the model. Women who underwent cesarean delivery and those with multiple pregnancies were excluded from the study. During the study period, there were 169,738 singleton vaginal deliveries, and 0.4% of the women suffered from PPF. Hypertensive disorders, induction of labor, dystocia of labor in the second stage, suspected fetal distress, meconium-stained amniotic fluid, postpartum hemorrhage, manual lysis of a retained placenta, and revision of the uterine cavity and cervix were found to be independently associated with PPF by multivariable analysis. Year of birth was found to be a risk factor for fever. Apgar scores lower than 7 at 1 but not 5 minutes were significantly higher in the PPF group. Perinatal mortality rates were significantly higher among women with PPF (6.7% versus 1.3%, odds ratio [OR] = 5.4; 95% confidence interval [CI] 3.9 to 7.3; P < 0.001). Using another multivariable analysis, with perinatal mortality as the outcome variable, PPF was found as an independent risk factor for perinatal mortality (OR = 2.9; 95% CI 1.9 to 4.6; P < 0.001). PPF in women undergoing vaginal deliveries is associated with adverse perinatal outcomes and specifically is an independent risk factor for perinatal mortality.

  5. Clinical outcomes of patients with hypothyroidism undergoing percutaneous coronary intervention

    Zhang, Ming; Sara, Jaskanwal D.S.; Matsuzawa, Yasushi; Gharib, Hossein; Bell, Malcolm R.; Gulati, Rajiv; Lerman, Lilach O.

    2016-01-01

    Abstract Aims The aim of this study was to investigate the association between hypothyroidism and major adverse cardiovascular and cerebral events (MACCE) in patients undergoing percutaneous coronary intervention (PCI). Methods and results Two thousand four hundred and thirty patients who underwent PCI were included. Subjects were divided into two groups: hypothyroidism ( n = 686) defined either as a history of hypothyroidism or thyroid-stimulating hormone (TSH) ≥5.0 mU/mL, and euthyroidism ( n = 1744) defined as no history of hypothyroidism and/or 0.3 mU/mL ≤ TSH hypothyroidism were further categorized as untreated ( n = 193), or those taking thyroid replacement therapy (TRT) with adequate replacement (0.3 mU/mL ≤ TSH hypothyroidism compared with those with euthyroidism (MACCE: HR: 1.28, P = 0.0001; myocardial infarction (MI): HR: 1.25, P = 0.037; heart failure: HR: 1.46, P = 0.004; revascularization: HR: 1.26, P = 0.0008; stroke: HR: 1.62, P = 0.04). Compared with untreated patients or those with inadequate replacement, adequately treated hypothyroid patients had a lower risk of MACCE (HR: 0.69, P = 0.005; HR: 0.78, P = 0.045), cardiac death (HR: 0.43, P = 0.008), MI (HR: 0.50, P = 0.0004; HR: 0.60, P = 0.02), and heart failure (HR: 0.50, P = 0.02; HR: 0.52, P = 0.017). Conclusion Hypothyroidism is associated with a higher incidence of MACCE compared with euthyroidism in patients undergoing PCI. Maintaining adequate control on TRT is beneficial in preventing MACCE. PMID:26757789

  6. Quality of Life in Elderly Cancer Patients Undergoing Chemotherapy.

    Lavdaniti, Maria; Zyga, Sofia; Vlachou, Eugenia; Sapountzi-Krepia, Despina

    2017-01-01

    As life expectancy increases, it is expected that 60% of all cases of cancer will be detected in elderly patients in the next two decades. Cancer treatment for older persons is complicated by a number of factors, thus negatively affecting patients' quality of life. The purpose of this study is to investigate quality of life in elderly cancer patients undergoing chemotherapy. This study was descriptive and non-experimental. It was conducted in one large hospital in a major city of Northern Greece. The sample was convenience comprising 53 elderly cancer patients undergoing cycle 3 chemotherapy. The data was collected using the Functional Assessment of Cancer Therapy scale and included questions related to demographic and clinical characteristics. The majority of participants were men (n = 27, 50.9%) who were married (n = 32, 79.5%). Their mean age was 70.07 ± 3.60. Almost half of the sample (n = 30, 56.6%) had colon cancer. There was a statistical significant difference between men and women pertaining to physical wellbeing (p = 0.004) and overall quality of life (p family wellbeing (p = 0.029), functional wellbeing (p = 0.09) and overall quality of life (p family wellbeing (p = 0.029). These findings call attention to quality of life and its related factors in elderly cancer patients. It is highly recommended to envisage measures for improving quality of life in this group of cancer patients.

  7. Psychological determinants of life satisfaction in women undergoing infertility treatment

    Aleksandra Anna Dembińska

    2016-01-01

    Full Text Available Background Infertility treatment is a long-term process, spread out over months, or even years, and carries no guarantee of success. It generates an incessant state of uncertainty which becomes a chronic state of psychological discomfort. Each stage of treatment may become a source of more trouble. Women deciding to undergo infertility treatment are exposed to many negative feelings concerning different aspects of their life. Participants and procedure The present study was an attempt to understand psychological determinants of life satisfaction in women undergoing infertility treatment. The study group included 470 women treated for infertility. Results Patients perceiving more social support in general, as well as more of the support types used in the study, i.e. emotional, instrumental, informational and institutional support, and support from family and friends, have better self-esteem, higher acceptance of their infertility, higher satisfaction with life, higher hope as an emotional state, and lower levels of anxiety and depression. Three negative emotional states, i.e. anxiety, depression and irritation, are predictors influencing (lowering life satisfaction of women struggling with infertility. The strongest of these predictors is depression, which is also a factor lowering the acceptance of one’s own infertility. The conducted analyses revealed that predictors influencing the life satisfaction of patients treated for infertility are self-esteem and acceptance of one’s own infertility (apart from the aforementioned emotional state – anxiety, depression, irritation. It was found that the higher the self-esteem and acceptance of one’s own infertility, the higher was the satisfaction with life. Conclusions Knowledge of these determinants is extremely valuable for medical personnel conducting treatments, because, according to many studies, the psychological state of women suffering from procreation problems is connected not only with

  8. Emotional state and coping style among gynecologic patients undergoing surgery.

    Matsushita, Toshiko; Murata, Hinako; Matsushima, Eisuke; Sakata, Yu; Miyasaka, Naoyuki; Aso, Takeshi

    2007-02-01

    The aim of the present study was to investigate changes in emotional state and the relationship between emotional state and demographic/clinical factors and coping style among gynecologic patients undergoing surgery. Using the Japanese version of the Profile of Mood States (POMS), 90 patients (benign disease: 32, malignancy: 58) were examined on three occasions: before surgery, before discharge, and 3 months after discharge. They were also examined using the Coping Inventory for Stressful Situations (CISS) on one occasion before discharge. The scores for the subscales depression, anger, and confusion were the highest after discharge while those for anxiety were the highest before surgery. The average scores of the POMS subscales for all subjects were within the normal range. With regard to the relationship between these emotional states and other factors, multiple regressions showed that the principal determinants of anxiety before surgery were religious belief, psychological symptoms during hospitalization and emotion-oriented (E) coping style; further, it was found that depression after discharge could be explained by chemotherapy, duration of hospitalization, and E coping style. The principal determinants of anger after discharge and vigor before surgery were length of education and E coping style, and severity of disease, chemotherapy, E coping style and task-oriented coping style, respectively. Those of post-discharge fatigue and confusion were length of education, psychological symptoms, and E coping style. In summary it is suggested that the following should be taken into account in patients undergoing gynecologic surgery: anxiety before surgery, depression, anger, and confusion after surgery, including coping styles.

  9. Performance of PROMIS for Healthy Patients Undergoing Meniscal Surgery.

    Hancock, Kyle J; Glass, Natalie; Anthony, Chris A; Hettrich, Carolyn M; Albright, John; Amendola, Annunziato; Wolf, Brian R; Bollier, Matthew

    2017-06-07

    The Patient-Reported Outcomes Measurement Information System (PROMIS) was developed as an extensive question bank with multiple health domains that could be utilized for computerized adaptive testing (CAT). In the present study, we investigated the use of the PROMIS Physical Function CAT (PROMIS PF CAT) in an otherwise healthy population scheduled to undergo surgery for meniscal injury with the hypotheses that (1) the PROMIS PF CAT would correlate strongly with patient-reported outcome instruments that measure physical function and would not correlate strongly with those that measure other health domains, (2) there would be no ceiling effects, and (3) the test burden would be significantly less than that of the traditional measures. Patients scheduled to undergo meniscal surgery completed the PROMIS PF CAT, Knee injury and Osteoarthritis Outcome Score (KOOS), Marx Knee Activity Rating Scale, Short Form-36 (SF-36), and EuroQol-5 Dimension (EQ-5D) questionnaires. Correlations were defined as high (≥0.7), high-moderate (0.61 to 0.69), moderate (0.4 to 0.6), moderate-weak (0.31 to 0.39), or weak (≤0.3). If ≥15% respondents to a patient-reported outcome measure obtained the highest or lowest possible score, the instrument was determined to have a significant ceiling or floor effect. A total of 107 participants were analyzed. The PROMIS PF CAT had a high correlation with the SF-36 Physical Functioning (PF) (r = 0.82, p ceiling effects, with 0% of the participants achieving the lowest and highest score, respectively. The PROMIS PF CAT correlates strongly with currently used patient-reported outcome measures of physical function and demonstrates no ceiling effects for patients with meniscal injury requiring surgery. It may be a reasonable alternative to more burdensome patient-reported outcome measures.

  10. Preoperative autologous plateletpheresis in patients undergoing open heart surgery.

    Tomar, Akhlesh S; Tempe, Deepak K; Banerjee, Amit; Hegde, Radhesh; Cooper, Andrea; Khanna, S K

    2003-07-01

    Blood conservation is an important aspect of care provided to the patients undergoing cardiac operations with cardiopulmonary bypass (CPB). It is even more important in patients with anticipated prolonged CPB, redo cardiac surgery, patients having negative blood group and in patients undergoing emergency cardiac surgery. In prolonged CPB the blood is subjected to more destruction of important coagulation factors, in redo surgery the separation of adhesions leads to increased bleeding and difficulty in achieving the haemostasis and in patients with negative blood group and emergency operations, the availability of sufficient blood can be a problem. Harvesting the autologous platelet rich plasma (PRP) can be a useful method of blood conservation in these patients. The above four categories of patients were prospectively studied, using either autologous whole blood donation or autologous platelet rich plasma (PRP) harvest in the immediate pre-bypass period. Forty two patients were included in the study and randomly divided into two equal groups of 21 each, control group (Group I) in which one unit of whole blood was withdrawn, and PRP group (Group II) where autologous plateletpheresis was utilised. After reversal of heparin, autologous whole blood was transfused in the control group and autologous PRP was transfused in the PRP group. The chest tube drainage and the requirement of homologous blood and blood products were recorded. Average PRP harvest was 643.33 +/- 133.51 mL in PRP group and the mean whole blood donation was 333.75 +/- 79.58 mL in the control group. Demographic, preoperative and intra operative data showed no statistically significant differences between the two groups. The PRP group patients drained 26.44% less (pblood products (pconservation in terms of better haemostasis, and less requirement of blood and blood products in the postoperative period as compared with the autologous whole blood donation. This technique can be especially useful in the

  11. Investigating the conformational stability of prion strains through a kinetic replication model.

    Mattia Zampieri

    2009-07-01

    Full Text Available Prion proteins are known to misfold into a range of different aggregated forms, showing different phenotypic and pathological states. Understanding strain specificities is an important problem in the field of prion disease. Little is known about which PrP(Sc structural properties and molecular mechanisms determine prion replication, disease progression and strain phenotype. The aim of this work is to investigate, through a mathematical model, how the structural stability of different aggregated forms can influence the kinetics of prion replication. The model-based results suggest that prion strains with different conformational stability undergoing in vivo replication are characterizable in primis by means of different rates of breakage. A further role seems to be played by the aggregation rate (i.e. the rate at which a prion fibril grows. The kinetic variability introduced in the model by these two parameters allows us to reproduce the different characteristic features of the various strains (e.g., fibrils' mean length and is coherent with all experimental observations concerning strain-specific behavior.

  12. Influence of weld discontinuities on strain controlled fatigue behavior of 308 stainless steel weld metal

    Bhanu Sankara Rao, K.; Valsan, M.; Sandhya, R.; Mannan, S.L.; Rodriguez, P.

    1994-01-01

    Detailed investigations have been performed for assessing the importance of weld discontinuities in strain controlled low cycle fatigue (LCF) behavior of 308 stainless steel (SS) welds. The LCF behavior of 308 SS welds containing defects was compared with that of type 304 SS base material and 308 SS sound weld metal. Weld pads were prepared by shielded metal arc welding process. Porosity and slag inclusions were introduced deliberately into the weld metal by grossly exaggerating the conditions normally causing such defects. Total axial strain controlled LCF tests have been conducted in air at 823 K on type 304 SS base and 308 SS sound weld metal employing strain amplitudes in the range from ±0.25 to ±0.8 percent. A single strain amplitude of ±0.25 percent was used for all the tests conducted on weld samples containing defects. The results indicated that the base material undergoes cyclic hardening whereas sound and defective welds experience cyclic softening. Base metal showed higher fatigue life than sound weld metal at all strain amplitudes. The presence of porosity and slag inclusions in the weld metal led to significant reduction in life. Porosity on the specimen surface has been found to be particularly harmful and caused a reduction in life by a factor of seven relative to sound weld metal

  13. The p - n junction under nonuniform strains: general theory and application to photovoltaics

    Guin, L.; Jabbour, M. E.; Triantafyllidis, N.

    2018-01-01

    It is well known that mechanical strains influence the electronic properties of semiconductor devices. Modeling the fully coupled mechanical, electrical, and electronic responses of semiconductors is therefore essential for predicting the effects of mechanical loading on their overall electronic response. In the first part of this paper, we develop a general continuum model that couples the mechanical, electrical, and electronic responses of a finitely deformable semiconductor. The proposed model accounts for the dependence of the band edge energies, densities of states, and electronic mobilities on strain. The governing equations are derived from the basic principles of the thermomechanics of electromagnetic continua undergoing electronic transport. In particular, we find that there exists electronically induced strains that can exceed their electromagnetic (Maxwell) counterparts by an order of magnitude. In the second part, motivated by applications that involve the bending of a photovoltaic cell, we use asymptotic methods to compute the current-voltage characteristic of a p - n junction under nonuniform strains. We find that, for a typical monocrystalline silicon solar cell, the changes in dark current are significant, i.e., of the order of 20% for strains of 0.2%.

  14. Noninvasive characterization of carotid plaque strain.

    Khan, Amir A; Sikdar, Siddhartha; Hatsukami, Thomas; Cebral, Juan; Jones, Michael; Huston, John; Howard, George; Lal, Brajesh K

    2017-06-01

    Current risk stratification of internal carotid artery plaques based on diameter-reducing percentage stenosis may be unreliable because ischemic stroke results from plaque disruption with atheroembolization. Biomechanical forces acting on the plaque may render it vulnerable to rupture. The feasibility of ultrasound-based quantification of plaque displacement and strain induced by hemodynamic forces and their relationship to high-risk plaques have not been determined. We studied the feasibility and reliability of carotid plaque strain measurement from clinical B-mode ultrasound images and the relationship of strain to high-risk plaque morphology. We analyzed carotid ultrasound B-mode cine loops obtained in patients with asymptomatic ≥50% stenosis during routine clinical scanning. Optical flow methods were used to quantify plaque motion and shear strain during the cardiac cycle. The magnitude (maximum absolute shear strain rate [MASSR]) and variability (entropy of shear strain rate [ESSR] and variance of shear strain rate [VSSR]) of strain were combined into a composite shear strain index (SSI), which was assessed for interscan repeatability and correlated with plaque echolucency. Nineteen patients (mean age, 70 years) constituting 36 plaques underwent imaging; 37% of patients (n = 7) showed high strain (SSI ≥0.5; MASSR, 2.2; ESSR, 39.7; VSSR, 0.03) in their plaques; the remaining clustered into a low-strain group (SSI routine B-mode imaging using clinical ultrasound machines. High plaque strain correlates with known high-risk echolucent morphology. Strain measurement can complement identification of patients at high risk for plaque disruption and stroke. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  15. Family resources study: part 1: family resources, family function and caregiver strain in childhood cancer.

    Panganiban-Corales, Avegeille T; Medina, Manuel F

    2011-10-31

    Severe illness can disrupt family life, cause family dysfunction, strain resources, and cause caregiver burden. The family's ability to cope with crises depends on their resources. This study sought to assess families of children with cancer in terms of family function-dysfunction, family caregiver strain and the adequacy of family resources using a new family resources assessment instrument. This is a cross-sectional study involving 90 Filipino family caregivers of children undergoing cancer treatment. This used a self-administered questionnaire composed of a new 12-item family resources questionnaire (SCREEM-RES) based on the SCREEM method of analysis, Family APGAR to assess family function-dysfunction; and Modified Caregiver Strain Index to assess strain in caring for the patient. More than half of families were either moderately or severely dysfunctional. Close to half of caregivers were either predisposed to strain or experienced severe strain, majority disclosed that their families have inadequate economic resources; many also report inaccessibility to medical help in the community and insufficient educational resources to understand and care for their patients. Resources most often reported as adequate were: family's faith and religion; help from within the family and from health providers. SCREEM-RES showed to be reliable with Cronbach's alpha of 0.80. There is good inter-item correlation between items in each domain: 0.24-0.70. Internal consistency reliability for each domain was also good: 0.40-0.92. Using 2-point scoring system, Cronbach's alpha were slightly lower: full scale (0.70) and for each domain 0.26-.82. Results showed evidence of association between family resources and family function based on the family APGAR but none between family resources and caregiver strain and between family function and caregiver strain. Many Filipino families of children with cancer have inadequate resources, especially economic; and are moderately or severely

  16. Family resources study: part 1: family resources, family function and caregiver strain in childhood cancer

    Panganiban-Corales Avegeille T

    2011-10-01

    Full Text Available Abstract Background Severe illness can disrupt family life, cause family dysfunction, strain resources, and cause caregiver burden. The family's ability to cope with crises depends on their resources. This study sought to assess families of children with cancer in terms of family function-dysfunction, family caregiver strain and the adequacy of family resources using a new family resources assessment instrument. Methods This is a cross-sectional study involving 90 Filipino family caregivers of children undergoing cancer treatment. This used a self-administered questionnaire composed of a new 12-item family resources questionnaire (SCREEM-RES based on the SCREEM method of analysis, Family APGAR to assess family function-dysfunction; and Modified Caregiver Strain Index to assess strain in caring for the patient. Results More than half of families were either moderately or severely dysfunctional. Close to half of caregivers were either predisposed to strain or experienced severe strain, majority disclosed that their families have inadequate economic resources; many also report inaccessibility to medical help in the community and insufficient educational resources to understand and care for their patients. Resources most often reported as adequate were: family's faith and religion; help from within the family and from health providers. SCREEM-RES showed to be reliable with Cronbach's alpha of 0.80. There is good inter-item correlation between items in each domain: 0.24-0.70. Internal consistency reliability for each domain was also good: 0.40-0.92. Using 2-point scoring system, Cronbach's alpha were slightly lower: full scale (0.70 and for each domain 0.26-.82. Results showed evidence of association between family resources and family function based on the family APGAR but none between family resources and caregiver strain and between family function and caregiver strain. Conclusion Many Filipino families of children with cancer have inadequate

  17. Computational Strain Gradient Crystal Plasticity

    Niordson, Christian Frithiof; Kysar, Jeffrey W.

    2011-01-01

    A model for strain gradient crystal visco-plasticity is formulated along the lines proposed by Fleck andWillis (2009) for isotropic plasticity. Size-effects are included in the model due to the addition of gradient terms in both the free energy as well as through a dissipation potential. A finite...... element solution method is presented, which delivers the slip-rate field and the velocity-field based on two minimum principles. Some plane deformation problems relevant for certain specific orientations of a face centered cubic crystal under plane loading conditions are studied, and effective in......-plane parameters are developed based on the crystallographic properties of the material. The problem of cyclic shear of a single crystal between rigid platens is studied as well as void growth of a cylindrical void....

  18. Vibrio parahaemolyticus Strains of Pandemic Serotypes Identified from Clinical and Environmental Samples from Jiangsu, China

    Jingjiao eLi

    2016-05-01

    Full Text Available Vibrio parahaemolyticus has emerged as a major foodborne pathogen in China, Japan, Thailand and other Asian countries. In this study, 72 strains of V. parahaemolyticus were isolated from clinical and environmental samples between 2006 and 2014 in Jiangsu, China. The serotypes and six virulence genes including thermostable direct hemolysin (TDR and TDR-related hemolysin (TRH genes were assessed among the isolates. Twenty five serotypes were identified and O3:K6 was one of the dominant serotypes. The genetic diversity was assessed by multilocus sequence typing (MLST analysis, and 48 sequence types (STs were found, suggesting this V. parahaemolyticus group is widely dispersed and undergoing rapid evolution. A total of 25 strains of pandemic serotypes such as O3:K6, O5:K17 and O1:KUT were identified. It is worth noting that the pandemic serotypes were not exclusively identified from clinical samples, rather, nine strains were also isolated from environmental samples; and some of these strains harbored several virulence genes, which may render those strains pathogenicity potential. Therefore, the emergence of these environmental pandemic V. parahaemolyticus strains may poses a new threat to the public health in China. Furthermore, six novel serotypes and 34 novel STs were identified among the 72 isolates, indicating that V. parahaemolyticus were widely distributed and fast evolving in the environment in Jiangsu, China. The findings of this study provide new insight into the phylogenic relationship between V. parahaemolyticus strains of pandemic serotypes from clinical and environmental sources and enhance the MLST database; and our proposed possible O- and K- antigen evolving paths of V. parahaemolyticus may help understand how the serotypes of this dispersed bacterial population evolve.

  19. Formal education of patients about to undergo laparoscopic cholecystectomy.

    Gurusamy, Kurinchi Selvan; Vaughan, Jessica; Davidson, Brian R

    2014-02-28

    Generally, before being operated on, patients will be given informal information by the healthcare providers involved in the care of the patients (doctors, nurses, ward clerks, or healthcare assistants). This information can also be provided formally in different formats including written information, formal lectures, or audio-visual recorded information. To compare the benefits and harms of formal preoperative patient education for patients undergoing laparoscopic cholecystectomy. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 2, 2013), MEDLINE, EMBASE, and Science Citation Index Expanded to March 2013. We included only randomised clinical trials irrespective of language and publication status. Two review authors independently extracted the data. We planned to calculate the risk ratio with 95% confidence intervals (CI) for dichotomous outcomes, and mean difference (MD) or standardised mean difference (SMD) with 95% CI for continuous outcomes based on intention-to-treat analyses when data were available. A total of 431 participants undergoing elective laparoscopic cholecystectomy were randomised to formal patient education (215 participants) versus standard care (216 participants) in four trials. The patient education included verbal education, multimedia DVD programme, computer-based multimedia programme, and Power Point presentation in the four trials. All the trials were of high risk of bias. One trial including 212 patients reported mortality. There was no mortality in either group in this trial. None of the trials reported surgery-related morbidity, quality of life, proportion of patients discharged as day-procedure laparoscopic cholecystectomy, the length of hospital stay, return to work, or the number of unplanned visits to the doctor. There were insufficient details to calculate the mean difference and 95% CI for the difference in pain scores at 9 to 24 hours (1 trial; 93 patients); and we did not identify clear evidence of

  20. Thermoresistance in radioresistant strains of 'Drosophila nebulosa'

    Kratz, F.L.

    1977-01-01

    The detection of thermoresistance in radioresistant strains of 'D. nebulosa' is described, as well as some conclusions on the genetic nature of these differences are presented. The strains used in this experiment were MF 204, from 'Morro de Ferro', in Pocos de Caldas (MG) (one of the biggest radioactive anomalies in the world) whose radioresistance is due to its additive genetic components (Kratz, 1973 and 1975); 85(87) R, an induced radioresistant strain; and MF K a control 'pooled' strain obtained near 'Morro do Ferro'. Survival tests, 72 hours after temperature shocks, performed in the interval of 36 0 C to 39 0 C showed a decreasing gradient of thermoresistance with the following regression coefficients: MF 204 b= - 5,4; 85(87)R b= - 7,2 and MF K b= - 7,9. Bifactorial analysis (strains and sexes) performed at 38 0 C and 39 0 C confirmed differences among strains (P [pt

  1. The many shades of prion strain adaptation.

    Baskakov, Ilia V

    2014-01-01

    In several recent studies transmissible prion disease was induced in animals by inoculation with recombinant prion protein amyloid fibrils produced in vitro. Serial transmission of amyloid fibrils gave rise to a new class of prion strains of synthetic origin. Gradual transformation of disease phenotypes and PrP(Sc) properties was observed during serial transmission of synthetic prions, a process that resembled the phenomenon of prion strain adaptation. The current article discusses the remarkable parallels between phenomena of prion strain adaptation that accompanies cross-species transmission and the evolution of synthetic prions occurring within the same host. Two alternative mechanisms underlying prion strain adaptation and synthetic strain evolution are discussed. The current article highlights the complexity of the prion transmission barrier and strain adaptation and proposes that the phenomenon of prion adaptation is more common than previously thought.

  2. Effect of strain rate and temperature at high strains on fatigue behavior of SAP alloys

    Blucher, J.T.; Knudsen, Per; Grant, N.J.

    1968-01-01

    Fatigue behavior of three SAP alloys of two nominal compositions (7 and 13% Al2O3) was studied in terms of strain rate and temperature at high strains; strain rate had no effect on life at 80 F, but had increasingly greater effect with increasing temperature above 500 F; life decreased with decre......Fatigue behavior of three SAP alloys of two nominal compositions (7 and 13% Al2O3) was studied in terms of strain rate and temperature at high strains; strain rate had no effect on life at 80 F, but had increasingly greater effect with increasing temperature above 500 F; life decreased...

  3. [Pharmacokinetics of flomoxef in children undergoing chronic hemodialysis].

    Sasagawa, F; Nakano, T; Mito, Y; Sekine, O

    1993-07-01

    The pharmacokinetics of flomoxef (FMOX), an oxacephem antibiotic, were investigated in pediatric patients undergoing chronic hemodialysis. The results are summarized as follows. 1. FMOX was given intravenously in a single dose of 10 mg/kg to 5 pediatric patients (ranging from 7 to 15 years of age) undergoing chronic hemodialysis. It was also given in a dose of 5 mg/kg to 2 of these patients. Its concentrations in serum and urine were determined using bioassay. Pharmacokinetic analyses were performed using a two compartment open model. 2. The serum concentrations of FMOX, administered in doses of 10 mg/kg or 5 mg/kg on non-hemodialysis days, were 33.3 +/- 4.09 micrograms/ml (mean +/- standard deviation) and 17.6 micrograms/ml (mean) at 30 minutes after injection, 29.6 +/- 3.51 micrograms/ml and 15.9 micrograms/ml at 1 hour, 27.2 +/- 2.14 micrograms/ml and 15.1 micrograms/ml at 2 hours, 23.5 +/- 1.90 micrograms/ml and 13.0 micrograms/ml at 4 hours, 20.8 +/- 2.44 micrograms/ml and 12.2 micrograms/ml at 6 hours, 18.9 +/- 1.86 micrograms/ml and 11.0 micrograms/ml at 8 hours, and 9.64 +/- 1.43 micrograms/ml and 6.16 micrograms/ml at 24 hours, respectively. 3. The urinary concentrations of FMOX, administered in a dose of 10 mg/kg, were 42.4-123 micrograms/ml between 0-6 hours after injection, 14.1-52.5 micrograms/ml between 6-24 hours, and 2.86-23.7 micrograms/ml between 24-48 hours. The urinary excretion rate in the first 48 hours after injection ranged from 9.1 to 10.5%.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Levosimendan in Patients with Left Ventricular Dysfunction Undergoing Cardiac Surgery.

    Mehta, Rajendra H; Leimberger, Jeffrey D; van Diepen, Sean; Meza, James; Wang, Alice; Jankowich, Rachael; Harrison, Robert W; Hay, Douglas; Fremes, Stephen; Duncan, Andra; Soltesz, Edward G; Luber, John; Park, Soon; Argenziano, Michael; Murphy, Edward; Marcel, Randy; Kalavrouziotis, Dimitri; Nagpal, Dave; Bozinovski, John; Toller, Wolfgang; Heringlake, Matthias; Goodman, Shaun G; Levy, Jerrold H; Harrington, Robert A; Anstrom, Kevin J; Alexander, John H

    2017-05-25

    Levosimendan is an inotropic agent that has been shown in small studies to prevent or treat the low cardiac output syndrome after cardiac surgery. In a multicenter, randomized, placebo-controlled, phase 3 trial, we evaluated the efficacy and safety of levosimendan in patients with a left ventricular ejection fraction of 35% or less who were undergoing cardiac surgery with the use of cardiopulmonary bypass. Patients were randomly assigned to receive either intravenous levosimendan (at a dose of 0.2 μg per kilogram of body weight per minute for 1 hour, followed by a dose of 0.1 μg per kilogram per minute for 23 hours) or placebo, with the infusion started before surgery. The two primary end points were a four-component composite of death through day 30, renal-replacement therapy through day 30, perioperative myocardial infarction through day 5, or use of a mechanical cardiac assist device through day 5; and a two-component composite of death through day 30 or use of a mechanical cardiac assist device through day 5. A total of 882 patients underwent randomization, 849 of whom received levosimendan or placebo and were included in the modified intention-to-treat population. The four-component primary end point occurred in 105 of 428 patients (24.5%) assigned to receive levosimendan and in 103 of 421 (24.5%) assigned to receive placebo (adjusted odds ratio, 1.00; 99% confidence interval [CI], 0.66 to 1.54; P=0.98). The two-component primary end point occurred in 56 patients (13.1%) assigned to receive levosimendan and in 48 (11.4%) assigned to receive placebo (adjusted odds ratio, 1.18; 96% CI, 0.76 to 1.82; P=0.45). The rate of adverse events did not differ significantly between the two groups. Prophylactic levosimendan did not result in a rate of the short-term composite end point of death, renal-replacement therapy, perioperative myocardial infarction, or use of a mechanical cardiac assist device that was lower than the rate with placebo among patients with a

  5. Retrospective review of pelvic malignancies undergoing total pelvic exenteration

    Kuhrt Maureen P

    2012-06-01

    Patients undergoing TPE for colorectal tumors have improved survival when compared with patients undergoing exenteration for pelvic malignancies of other origins. Within the colorectal group, the extent of resection demonstrated a significant survival benefit of an R0 resection compared with R1 and R2 resections. Despite TPE carrying a high morbidity rate, mortality rates have improved and careful patient selection can optimize outcomes.

  6. PLASMA CYTOKINES LEVELS IN PATIENTS UNDERGOING LONG-TERM HAEMODIALYSIS

    D. S. Polyakov

    2011-01-01

    Full Text Available Аbstract.  Patients  with  end-stage  renal  disease  need  their  kidney  functions  to  be  replaced.  Chronic haemodialysis represents a most common method of such substitution treatment. This procedure results in successful survival of such patients for years. Chronic haemodialysis is accompanied by a complication which is known as β2-microglobulin amyloidosis. In this case, amyloid substance consisting of β2-microglobulin (β2-MG accumulates in bones, ligaments and joints. Biological causes of β2-MG amyloidosis are still not established. To elucidate the role of inflammation in the pathogenesis of β2-MG amyloidosis, the levels of  IL-2,  IL-4,  IL-6,  IL-8,  IL-10,  GM-CSF,  IFNγ, TNFα were quantified in plasma of patients undergoing  long-term haemodialysis. Mean amounts of all the mentioned cytokines in haemodialysis patients proved to be significantly higher than in control group consisting of healthy subjects. When comparing a group receiving standard  dialysis  procedure  versus  a  subgroup  receiving  haemodiafiltration,  a  single  reliable  difference  was revealed for GM-CSF levels (p < 0.04, without any differences shown for other cytokines. With increasing terms of chronic haemodialysis, the levels of IL-2, IL-4, IL-6, IL-8, GM-CSF, IFNγ, TNFα were increased, or, at least, they did not decrease. After three years of dialysis, IL-10 concentrations were statistically indistinguishable from normal levels. In patients undergoing haemodiafiltration, plasma levels of IL-2, IL-4, IL-8, GM-CSF, IFNγ, TNFα did not drop with increasing terms of dialysis. The levels of IL-6 and IL-10 decreased after three years of dialysis, to near-normal levels.In general, these results suggest that IL-10 and IL-6 may be regarded as candidates for further studies as potential markers of β2-microglobulin amyloidosis. (Med. Immunol., 2011, vol. 13, N 2-3, pp 211-218

  7. Preoperative autologous plateletpheresis in patients undergoing open heart surgery.

    Tomar Akhlesh

    2003-01-01

    Full Text Available Blood conservation is an important aspect of care provided to the patients undergoing cardiac operations with cardiopulmonary bypass (CPB. It is even more important in patients with anticipated prolonged CPB, redo cardiac surgery, patients having negative blood group and in patients undergoing emergency cardiac surgery. In prolonged CPB the blood is subjected to more destruction of important coagulation factors, in redo surgery the separation of adhesions leads to increased bleeding and difficulty in achieving the haemostasis and in patients with negative blood group and emergency operations, the availability of sufficient blood can be a problem. Harvesting the autologous platelet rich plasma (PRP can be a useful method of blood conservation in these patients. The above four categories of patients were prospectively studied, using either autologous whole blood donation or autologous platelet rich plasma (PRP harvest in the immediate pre-bypass period. Forty two patients were included in the study and randomly divided into two equal groups of 21 each, control group (Group I in which one unit of whole blood was withdrawn, and PRP group (Group II where autologous plateletpheresis was utilised. After reversal of heparin, autologous whole blood was transfused in the control group and autologous PRP was transfused in the PRP group. The chest tube drainage and the requirement of homologous blood and blood products were recorded. Average PRP harvest was 643.33 +/- 133.51 mL in PRP group and the mean whole blood donation was 333.75 +/- 79.58 mL in the control group. Demographic, preoperative and intra operative data showed no statistically significant differences between the two groups. The PRP group patients drained 26.44% less (p<0.001 and required 38.5% less homologous blood and blood products (p<0.05, in the postoperative period. Haemoglobin levels on day zero (day of operation and day three were statistically not different between the two groups. We

  8. Surface instabilities during straining of anisotropic materials

    Legarth, Brian Nyvang; Richelsen, Ann Bettina

    2006-01-01

    The development of instabilities in traction-free surfaces is investigated numerically using a unit cell model. Full finite strain analyses are conducted using isotropic as well as anisotropic yield criteria and both plane strain tension and compression are considered. In the load range of tensio...... of principal overall strain. For other orientations surface instabilities are seen when non-associated plastic flow is taken into account. Compared to tension, smaller compressive deformations are needed in order to initiate a surface instability....

  9. Strain comparisons in aquaculture species: a manual

    Ponzoni, R.W.; James, J.W.; Nguyen, N.H.; Mekkawy, W.; Khaw, H.L.

    2013-01-01

    When different strains or breeds of a particular species are available, the best choice is seldom immediately obvious for producers. Scientists are also interested in the relative performance of different strains because it provides a basis for recommendations to producers and it often stimulates the conduct of work aimed at unraveling the underlying biological mechanisms involved in the expression of such differences. Hence, strain or breed comparisons of some sort are frequently conducted. ...

  10. [Characteristics of Lactobacillus strains contained in pharmaceuticals].

    Banach, W; Bucholc, B; Wójcik, B

    2001-01-01

    The aim of the study was to characterize lactic acid bacteria (LAB) which are components of drugs administered orally in cases of intestinal disturbances, or antibiotic--related diarrhea. Biochemical properties, growth behavior, bile tolerance, and survival at low pH of six LAB strains (four strains L. rhamnosus and two L. acidophilus) were studied. The survival at low pH was determined in MRS broth (Difco) acidified to pH 1; 2; 3; and 4. Bile tolerance was tested on MRS broth with 0.3% oxgall (Difco). Between tested strains differences in ability to grow at low pH and survival in bile were observed. Only 0.01% inoculum of all examined strains survived at pH 1. Differences between strains in survival at low pH (pH 2 and pH 3) and tolerance of bile were observed. However, after 2 h incubation at pH 4, 100% of strains stayed alive. Examined strains demonstrated good 3% bile tolerance. All strains met the criteria for probiotic strains: ability to survive at pH 3 and in the presence of bile.

  11. Properties of strain gages at cryogenic temperature

    Shibata, Nobuo; Fujiyoshi, Toshimitsu.

    1978-01-01

    At the time of developing superconduction generators, the stress measurement for rotor parts is required to grasp the safety and performance of the rotor at cryogenic temperature, which is cooled with liquid helium. In case of carrying out the stress measurement with strain gages, the problems are as follows. The strain gages and lead wires are exposed to cryogenic temperature from 4 to 10 K and strong magnetic field of about 3T, and subjected to high centrifugal acceleration of about 500G. In order to establish the techniques of the stress measurement under such conditions, the adhesives and damp-proof coatings for strain gages and strain gages themselves in Japan and foreign countries were examined on the properties at cryogenic temperature. As for the properties of strain gages, mainly the apparent strain owing to temperature change was investigated, and the change of the gage factors was studies only at liquid nitrogen temperature. The stress measurement with strain gages at low temperature had been studied in detail down to liquid nitrogen temperature concerning LNG tanks. The experimental apparatus, the samples, the testing methods and the test results of cooling tests on adhesives and damp-proof coatings, and the temperature characteristics of strain gages are reported. The usable adhesives and coatings were found, and correction by accurate temperature measurement is required for apparent strain. (Kako, I.)

  12. Mechanical properties of tannin-based rigid foams undergoing compression

    Celzard, A., E-mail: Alain.Celzard@enstib.uhp-nancy.fr [Institut Jean Lamour - UMR CNRS 7198, CNRS - Nancy-Universite - UPV-Metz, Departement Chimie et Physique des Solides et des Surfaces, ENSTIB, 27 rue du Merle Blanc, BP 1041, 88051 Epinal cedex 9 (France); Zhao, W. [Institut Jean Lamour - UMR CNRS 7198, CNRS - Nancy-Universite - UPV-Metz, Departement Chimie et Physique des Solides et des Surfaces, ENSTIB, 27 rue du Merle Blanc, BP 1041, 88051 Epinal cedex 9 (France); Pizzi, A. [ENSTIB-LERMAB, Nancy-University, 27 rue du Merle Blanc, BP 1041, 88051 Epinal cedex 9 (France); Fierro, V. [Institut Jean Lamour - UMR CNRS 7198, CNRS - Nancy-Universite - UPV-Metz, Departement Chimie et Physique des Solides et des Surfaces, ENSTIB, 27 rue du Merle Blanc, BP 1041, 88051 Epinal cedex 9 (France)

    2010-06-25

    The mechanical properties of a new class of extremely lightweight tannin-based materials, namely organic foams and their carbonaceous counterparts are detailed. Scaling laws are shown to describe correctly the observed behaviour. Information about the mechanical characteristics of the elementary forces acting within these solids is derived. It is suggested that organic materials present a rather bending-dominated behaviour and are partly plastic. On the contrary, carbon foams obtained by pyrolysis of the former present a fracture-dominated behaviour and are purely brittle. These conclusions are supported by the differences in the exponent describing the change of Young's modulus as a function of relative density, while that describing compressive strength is unchanged. Features of the densification strain also support such conclusions. Carbon foams of very low density may absorb high energy when compressed, making them valuable materials for crash protection.

  13. Comparison of Thermal Creep Strain Calculation Results Using Time Hardening and Strain Hardening Rules

    Kim, Junehyung; Cheon, Jinsik; Lee, Byoungoon; Lee, Chanbock

    2014-01-01

    One of the design criteria for the fuel rod in PGSFR is the thermal creep strain of the cladding, because the cladding is exposed to a high temperature for a long time during reactor operation period. In general, there are two kind of calculation scheme for thermal creep strain: time hardening and strain hardening rules. In this work, thermal creep strain calculation results for HT9 cladding by using time hardening and strain hardening rules are compared by employing KAERI's current metallic fuel performance analysis code, MACSIS. Also, thermal creep strain calculation results by using ANL's metallic fuel performance analysis code, LIFE-METAL which adopts strain hardening rule are compared with those by using MACSIS. Thermal creep strain calculation results for HT9 cladding by using time hardening and strain hardening rules were compared by employing KAERI's current metallic fuel performance analysis code, MACSIS. Also, thermal creep strain calculation results by using ANL's metallic fuel performance analysis code, LIFE-METAL which adopts strain hardening rule were compared with those by using MACSIS. Tertiary creep started earlier in time hardening rule than in strain hardening rule. Also, calculation results by MACSIS with strain hardening and those obtained by using LIFE-METAL were almost identical to each other

  14. Radiation exposure distribution in patients undergoing CT brain scans

    Yang Zhanshan; Feng Dinghua; Chang Zichi; Li Shijun

    1989-12-01

    The distribution of surface exposures in patients undergoing single and multiple computerized tomographic brain scans with Hitachi CT-W500 was measured by LiF(Mg, Ti) thermoluminescent dosimetry. It was found that there was no significant difference in the sufrace exposures from different scanning slices. However, the exposure doses at different scanning angles around the head were different significantly. The reference point of the maximum surface exposure was at the temporal part of the head. the maximum surface exposure was at 1.65 x 10 -3 C·kg -1 while the average exposure was 1.55 x 10 -3 C·kg -1 . The ratio of the average dose resulting from nine scans to that from a single scan was 1.3, and the surface exposure contribution of scattered radiation was computed. At the same time the radiation doses to eyes, thyroid, chest and gonads of patiens at corresponding position were also measured and were compared with those from CT cranial scans in children and skull radiographic procedures respectively

  15. The Meaning of Touch to Patients Undergoing Chemotherapy.

    Leonard, Katherine E; Kalman, Melanie

    2015-09-01

    To explore the experience of being touched in people diagnosed with cancer and undergoing IV chemotherapy.
 Qualitative, phenomenologic.
 Central New York and northern Pennsylvania, both in the northeastern United States
. 11 Caucasian, English-speaking adults.
. Individual interviews used open-ended questions to explore the meaning of being touched to each participant. Meanings of significant statements, which pertained to the phenomenon under investigation, were formulated hermeneutically. Themes were derived from immersion in the data and extraction of similar and divergent concepts among all interviews, yielding a multidimensional understanding of the meaning of being touched in this sample of participants
. Participants verbalized awareness of and sensitivity to the regard of others who were touching them, including healthcare providers, family, and friends. Patients do not classify a provider's touch as either task or comfort oriented. Meanings evolved in the context of three primary themes. The experience of being touched encompasses the quality of presence of providers, family, or friends. For touch to be regarded as positive, patients must be regarded as inherently whole and equal. The quality of how touch is received is secondary to and flows from the relationship established between patient and provider
. This study adds to the literature in its finding that the fundamental quality of the relationship between patient and provider establishes the perceived quality of touch. Previous studies have primarily divided touch into two categories.

  16. Measuring radiation dose to patients undergoing fluoroscopically-guided interventions

    Lubis, L E; Badawy, M K

    2016-01-01

    The increasing prevalence and complexity of fluoroscopically guided interventions (FGI) raises concern regarding radiation dose to patients subjected to the procedure. Despite current evidence showing the risk to patients from the deterministic effects of radiation (e.g. skin burns), radiation induced injuries remain commonplace. This review aims to increase the awareness surrounding radiation dose measurement for patients undergoing FGI. A review of the literature was conducted alongside previous researches from the authors’ department. Studies pertaining to patient dose measurement, its formalism along with current advances and present challenges were reviewed. Current patient monitoring techniques (using available radiation dosimeters), as well as the inadequacy of accepting displayed dose as patient radiation dose is discussed. Furthermore, advances in real-time patient radiation dose estimation during FGI are considered. Patient dosimetry in FGI, particularly in real time, remains an ongoing challenge. The increasing occurrence and sophistication of these procedures calls for further advances in the field of patient radiation dose monitoring. Improved measuring techniques will aid clinicians in better predicting and managing radiation induced injury following FGI, thus improving patient care. (paper)

  17. Oral changes in individuals undergoing hematopoietic stem cell transplantation

    Regina Haddad Barrach

    2015-04-01

    Full Text Available INTRODUCTION: Patients undergoing hematopoietic stem cell transplantation receive high doses of chemotherapy and radiotherapy, which cause severe immunosuppression.OBJECTIVE: To report an oral disease management protocol before and after hematopoietic stem cell transplantation.METHODS: A prospective study was carried out with 65 patients aged > 18 years, with hematological diseases, who were allocated into two groups: A (allogeneic transplant, 34 patients; B (autologous transplant, 31 patients. A total of three dental status assessments were performed: in the pre-transplantation period (moment 1, one week after stem cell infusion (moment 2, and 100 days after transplantation (moment 3. In each moment, oral changes were assigned scores and classified as mild, moderate, and severe risks.RESULTS: The most frequent pathological conditions were gingivitis, pericoronitis in the third molar region, and ulcers at the third moment assessments. However, at moments 2 and 3, the most common disease was mucositis associated with toxicity from the drugs used in the immunosuppression.CONCLUSION: Mucositis accounted for the increased score and potential risk of clinical complications. Gingivitis, ulcers, and pericoronitis were other changes identified as potential risk factors for clinical complications.

  18. Non-invasive anesthesia for children undergoing proton radiation therapy

    Owusu-Agyemang, Pascal; Grosshans, David; Arunkumar, Radha; Rebello, Elizabeth; Popovich, Shannon; Zavala, Acsa; Williams, Cynthia; Ruiz, Javier; Hernandez, Mike; Mahajan, Anita; Porche, Vivian

    2014-01-01

    Background: Proton therapy is a newer modality of radiotherapy during which anesthesiologists face specific challenges related to the setup and duration of treatment sessions. Purpose: Describe our anesthesia practice for children treated in a standalone proton therapy center, and report on complications encountered during anesthesia. Materials and methods: A retrospective review of anesthetic records for patients ⩽18 years of age treated with proton therapy at our institution between January 2006 and April 2013 was performed. Results: A total of 9328 anesthetics were administered to 340 children with a median age of 3.6 years (range, 0.4–14.2). The median daily anesthesia time was 47 min (range, 15–79). The average time between start of anesthesia to the start of radiotherapy was 7.2 min (range, 1–83 min). All patients received Total Intravenous Anesthesia (TIVA) with spontaneous ventilation, with 96.7% receiving supplemental oxygen by non-invasive methods. None required daily endotracheal intubation. Two episodes of bradycardia, and one episode each of; seizure, laryngospasm and bronchospasm were identified for a cumulative incidence of 0.05%. Conclusions: In this large series of children undergoing proton therapy at a freestanding center, TIVA without daily endotracheal intubation provided a safe, efficient, and less invasive option of anesthetic care

  19. [Influencing factors of reproduction status of patients undergoing laparoscopic myomectomy].

    Song, Guang-hui; Zhang, Song-ying; Li, Bai-jia; Wei, Wei; Huang, Dong; Lin, Xiao-na; Lou, Hong-ying

    2013-09-17

    To explore the influencing factors of reproduction status in women undergoing laparoscopic myomectomy (LM). A total of 278 LM patients were recruited.We retrospectively reviewed the reproduction status of 87 pregnant cases after LM. The correlations of their pregnancy outcomes and such clinical profiles as age, operative techniques, biological characteristics of fibroids (number, type, size and location) were analyzed.No uterine rupture occurred during the gestation period. None of them switched to open surgery due to laparoscopic difficulties. However, one patient had a laparoscopic suture for secondary bleeding of uterine incision. At 3 months post-operation, sonography showed no heterogeneous echo, effusion and hematoma in uterine incision.Incision through uterine cavity occurred intraoperatively in 8 cases, but no intrauterine adhesion was found on hysteroscopy 3 months later. And 87 women became pregnant and the postoperative fertilization time was from 2 months to 5 years. Age influenced the postoperative pregnancy rate.Other factors such as location, number and size of fibroid had no impact on fertility. For achieving a high conception rate and guaranteeing the safety of pregnant women, a clinician should select reasonable surgical approaches, perform accurate anatomical restoration, apply strict hemostasis and choose a right time of conception.

  20. Dosimetry for Patients undergoing Radiographic Examinations in Sudan

    Halato, M.A.; Kafi, S.T.; Ahmed, A.M.; Sid Ahamed, F.A.; Ibrahim, Z.; Suliman, M.F.; Suliman, I.I.

    2009-01-01

    In this study we estimated the entrance skin doses ESDs for patients undergoing selected diagnostic X -ray examinations in two large public hospitals in Khartoum state, Sudan. The study included the examinations of the chest posterior-anterior (PA) , skull antero-posterior (AP), skull Lateral (LAT) , Lumber spine AP/LAT, abdomen Intravenous urogram (IVU) and Pelvis AP. Totally, 241 patients were included in this study. ESDs were estimated from patients specific exposure parameters using established relation between output (μ Gy/mAs) and tube voltage (kVp). The estimated ESDs ranged from 0.18 - 1.05 mGy for chest PA, 0.98 - 3.48 mGy for Skull (AP), 0.66 - 2.75 mGy for skull (LAT), 1.22 - 4.35 mGy for abdomen (IVU), 1.18 - 5.75 mGy for Pelvis, 1.52 - 5.01 mGy Lumbar spine AP and 2.48 - 10.41 mGy for Lumbar spine (LAT). These values compare well with the international reference dose levels. This study provides additional data that can help the regulatory authority to establish reference dose level for diagnostic radiology in Sudan

  1. Psychosocial predictors of affect in adult patients undergoing orthodontic treatment.

    Peñacoba, Cecilia; González, M José; Santos, Noelia; Romero, Martín

    2014-02-01

    In this paper we propose to study the role of psychosocial variables in affect in adult patients undergoing orthodontic treatment, considering that affect is a key variable in treatment adherence. Seventy-four patients (average age 33,24 ± 10,56) with metal multibracket-fixed orthodontic treatment were included. Patients were assessed twice. The first stage, at the beginning of treatment, included assessment of dental impact (Psychosocial Impact of Dental Aesthetics Questionnaire), trait anxiety (State-Trait Anxiety Inventory), self-esteem (Rosenberg's self-esteem scale), and self-efficacy (General Self-efficacy Scale). In the second stage, 6 months later, positive and negative affect towards treatment was assessed using the Positive and Negative Affect Scale. Dental social impact differentiates between patients with high and low negative affect, while self-efficacy differentiates between patients with high and low positive affect. Trait anxiety and self-esteem differentiate between both types of affect (positive and negative). Trait anxiety and self-esteem (when trait anxiety weight is controlled) are significant predictor variables of affective balance. These results have important practical implications, because it seems essential to adopt a bio-psychosocial model incorporating assessment methods focusing on day-to-day changes in mood and well-being.

  2. Nitric oxide synthetase and Helicobacter pylori in patients undergoing appendicectomy.

    Kell, M R

    2012-02-03

    BACKGROUND: This study was designed to determine whether Helicobacter pylori forms part of the normal microenvironment of the appendix, whether it plays a role in the pathogenesis of acute appendicitis, and whether it is associated with increased expression of inducible nitric oxide synthetase (iNOS) in appendicular macrophages. METHODS: Serology for H. pylori was performed on 51 consecutive patients undergoing emergency appendicectomy. Appendix samples were tested for urease activity, cultured and stained for H. pylori, graded according to the degree of inflammatory infiltrate, and probed immunohistochemically for iNOS expression. RESULTS: The mean age of the patients was 21 (range 7-51) years. Seventeen patients (33 per cent) were seropositive for H. pylori but no evidence of H. pylori was found in any appendix specimen. However, an enhanced inflammatory cell infiltration was observed in seropositive patients (P < 0.04) and the expression of macrophage iNOS in the mucosa of normal and inflamed appendix specimens was increased (P < 0.01). CONCLUSION: H. pylori does not colonize the appendix and is unlikely to be a pathogenic stimulus for appendicitis. Priming effects on mucosal immunology downstream from the foregut may occur after infection with H. pylori.

  3. Emotional distress in patients undergoing Magnetic Resonance Imaging

    Mozzolillo, R.; Ercolani, P.; Giovagnoni, A.; Denigris, E.; Barbini, N.; Mariani, L.; Nardi, B.; Cotani, P.; Marchesi, G.F.

    1991-01-01

    MR imaging, like other imaging techniques, can cause emotional and psychological reactions in the patients. Although reversible, these reactions sometimes lead the patient to absolutely refuse the examination or to make it impossible to carry it through. To investigate the patients' emotional distress, a study group pf 28 subjects was examinated. They were heterogeneous in sex, age, and pathologic condition. The main psycological reactions were analyzed, and anxiety-both of state and of trait. The anxiety parameter was evaluated as a specific index in the psycho-behavioral modifications induced by MR examination. The influence was also considered of the 'fantasies' related to examination results on the patients' psyche. Talks and STAI X1 and STAI X2 were employed to this purpose, to identifi possible disturbing elements related to both patients' character and examination situations. Our results point to anxiety as the mayor reaction observed in the subjects undergoing MR examination; it seems to be related to different parameters, which are difficult to identify. Claustrophobia, pathophobia, and the fear of an unknown examination play a mayor role. Talking to the patients and informing them of the characteristics of the examination proved useful to significantly reduce their emotional distress

  4. Obesity Increases Operative Time in Children Undergoing Laparoscopic Cholecystectomy.

    Pandian, T K; Ubl, Daniel S; Habermann, Elizabeth B; Moir, Christopher R; Ishitani, Michael B

    2017-03-01

    Few studies have assessed the impact of obesity on laparoscopic cholecystectomy (LC) in pediatric patients. Children who underwent LC were identified from the 2012 to 2013 American College of Surgeons' National Surgical Quality Improvement Program Pediatrics data. Patient characteristics, operative details, and outcomes were compared. Multivariable logistic regression was utilized to identify predictors of increased operative time (OT) and duration of anesthesia (DOAn). In total, 1757 patients were identified. Due to low rates of obesity in children obese). Among obese children, 80.6% were girls. A higher proportion of obese patients had diabetes (3.0% versus 1.0%, P obesity was an independent predictor of OT >90 (odds ratio [OR] 2.02; 95% confidence interval [95% CI] 1.55-2.63), and DOAn >140 minutes (OR 1.86; 95% CI 1.42-2.43). Obesity is an independent risk factor for increased OT in children undergoing LC. Pediatric surgeons and anesthesiologists should be prepared for the technical and physiological challenges that obesity may pose in this patient population.

  5. Blood Transfusion Strategies in Patients Undergoing Extracorporeal Membrane Oxygenation

    Hyoung Soo Kim

    2017-02-01

    Full Text Available Extracorporeal membrane oxygenation (ECMO is frequently associated with bleeding and coagulopathy complications, which may lead to the need for transfusion of multiple blood products. However, blood transfusions are known to increase morbidity and mortality, as well as hospital cost, in critically ill patients. In current practice, patients on ECMO receive a transfusion, on average, of 1-5 packed red blood cells (RBCs/day, with platelet transfusion accounting for the largest portion of transfusion volume. Generally, adult patients require more transfusions than neonates or children, and patients receiving venovenous ECMO for respiratory failure tend to need smaller transfusion volumes compared to those receiving venoarterial ECMO for cardiac failure. Observation studies have reported that a higher transfusion volume was associated with increased mortality. To date, the evidence for transfusion in patients undergoing ECMO is limited; most knowledge on transfusion strategies was extrapolated from studies in critically ill patients. However, current data support a restrictive blood transfusion strategy for ECMO patients, and a low transfusion trigger seems to be safe and reasonable.

  6. Concomitant atrial fibrillation surgery for people undergoing cardiac surgery

    Huffman, Mark D; Karmali, Kunal N; Berendsen, Mark A; Andrei, Adin-Cristian; Kruse, Jane; McCarthy, Patrick M; Malaisrie, S C

    2016-01-01

    Background People with atrial fibrillation (AF) often undergo cardiac surgery for other underlying reasons and are frequently offered concomitant AF surgery to reduce the frequency of short- and long-term AF and improve short- and long-term outcomes. Objectives To assess the effects of concomitant AF surgery among people with AF who are undergoing cardiac surgery on short-term and long-term (12 months or greater) health-related outcomes, health-related quality of life, and costs. Search methods Starting from the year when the first “maze” AF surgery was reported (1987), we searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library (March 2016), MEDLINE Ovid (March 2016), Embase Ovid (March 2016), Web of Science (March 2016), the Database of Abstracts of Reviews of Effects (DARE, April 2015), and Health Technology Assessment Database (HTA, March 2016). We searched trial registers in April 2016. We used no language restrictions. Selection criteria We included randomised controlled trials evaluating the effect of any concomitant AF surgery compared with no AF surgery among adults with preoperative AF, regardless of symptoms, who were undergoing cardiac surgery for another indication. Data collection and analysis Two review authors independently selected studies and extracted data. We evaluated the risk of bias using the Cochrane ‘Risk of bias’ tool. We included outcome data on all-cause and cardiovascular-specific mortality, freedom from atrial fibrillation, flutter, or tachycardia off antiarrhythmic medications, as measured by patient electrocardiographic monitoring greater than three months after the procedure, procedural safety, 30-day rehospitalisation, need for post-discharge direct current cardioversion, health-related quality of life, and direct costs. We calculated risk ratios (RR) for dichotomous data with 95% confidence intervals (CI) using a fixed-effect model when heterogeneity was low (I2 ≤ 50%) and random

  7. Controlled invasive mechanical ventilation strategies in obese patients undergoing surgery.

    Maia, Lígia de Albuquerque; Silva, Pedro Leme; Pelosi, Paolo; Rocco, Patricia Rieken Macedo

    2017-06-01

    The obesity prevalence is increasing in surgical population. As the number of obese surgical patients increases, so does the demand for mechanical ventilation. Nevertheless, ventilatory strategies in this population are challenging, since obesity results in pathophysiological changes in respiratory function. Areas covered: We reviewed the impact of obesity on respiratory system and the effects of controlled invasive mechanical ventilation strategies in obese patients undergoing surgery. To date, there is no consensus regarding the optimal invasive mechanical ventilation strategy for obese surgical patients, and no evidence that possible intraoperative beneficial effects on oxygenation and mechanics translate into better postoperative pulmonary function or improved outcomes. Expert commentary: Before determining the ideal intraoperative ventilation strategy, it is important to analyze the pathophysiology and comorbidities of each obese patient. Protective ventilation with low tidal volume, driving pressure, energy, and mechanical power should be employed during surgery; however, further studies are required to clarify the most effective ventilation strategies, such as the optimal positive end-expiratory pressure and whether recruitment maneuvers minimize lung injury. In this context, an ongoing trial of intraoperative ventilation in obese patients (PROBESE) should help determine the mechanical ventilation strategy that best improves clinical outcome in patients with body mass index≥35kg/m 2 .

  8. Completed Gravity Probe B Undergoes Thermal Vacuum Testing

    2000-01-01

    The Gravity Probe B (GP-B) is the relativity experiment developed at Stanford University to test two extraordinary predictions of Albert Einstein's general theory of relativity. The experiment will measure, very precisely, the expected tiny changes in the direction of the spin axes of four gyroscopes contained in an Earth-orbiting satellite at a 400-mile altitude. So free are the gyroscopes from disturbance that they will provide an almost perfect space-time reference system. They will measure how space and time are very slightly warped by the presence of the Earth, and, more profoundly, how the Earth's rotation very slightly drags space-time around with it. These effects, though small for the Earth, have far-reaching implications for the nature of matter and the structure of the Universe. In this photograph, the completed space vehicle is undergoing thermal vacuum environment testing. GP-B is among the most thoroughly researched programs ever undertaken by NASA. This is the story of a scientific quest in which physicists and engineers have collaborated closely over many years. Inspired by their quest, they have invented a whole range of technologies that are already enlivening other branches of science and engineering. Launched April 20, 2004 , the GP-B program was managed for NASA by the Marshall Space Flight Center. Development of the GP-B is the responsibility of Stanford University along with major subcontractor Lockheed Martin Corporation. (Image credit to Russ Underwood, Lockheed Martin Corporation.)

  9. Cardiovascular impact in patients undergoing maintenance hemodialysis: Clinical management considerations.

    Chirakarnjanakorn, Srisakul; Navaneethan, Sankar D; Francis, Gary S; Tang, W H Wilson

    2017-04-01

    Patients undergoing maintenance hemodialysis develop both structural and functional cardiovascular abnormalities. Despite improvement of dialysis technology, cardiovascular mortality of this population remains high. The pathophysiological mechanisms of these changes are complex and not well understood. It has been postulated that several non-traditional, uremic-related risk factors, especially the long-term uremic state, which may affect the cardiovascular system. There are many cardiovascular changes that occur in chronic kidney disease including left ventricular hypertrophy, myocardial fibrosis, microvascular disease, accelerated atherosclerosis and arteriosclerosis. These structural and functional changes in patients receiving chronic dialysis make them more susceptible to myocardial ischemia. Hemodialysis itself may adversely affect the cardiovascular system due to non-physiologic fluid removal, leading to hemodynamic instability and initiation of systemic inflammation. In the past decade there has been growing awareness that pathophysiological mechanisms cause cardiovascular dysfunction in patients on chronic dialysis, and there are now pharmacological and non-pharmacological therapies that may improve the poor quality of life and high mortality rate that these patients experience. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. [Psychosocial adjustment in colorectal cancer patients undergoing chemotherapy or chemoradiotherapy].

    Alvarado-Aguilar, Salvador; Guerra-Cruz, Hilda Griselda; Cupil-Rodríguez, Aura Lizbet; Calderillo-Ruiz, Germán; Oñate-Ocaña, Luis Fernando

    2011-01-01

    Psychosocial adaptation is a measurement that represents the patient's adjustment to those changes involved in their illness. We undertook this study to search for individual characteristics and clinical aspects associated with successful psychosocial adjustment in patients with colorectal cancer (CRC) undergoing (CT) chemotherapy or chemoradiotherapy (CRT). Seventy-five patients with CRC treated with CT or CRT in a cancer center were included. Psychosocial Adjustment to Illness Scale Self-Reporting (PAIS-SR) questionnaire was used as a measurement of psychosocial adjustment. Psychosocial adaptation was successful in 18 patients (24%) and unsuccessful in 57 patients (76%). Young patients, married patients and males showed lower psychosocial adaptation to disease. This is associated with the decrease in sexual relations, economic resources and psychological symptoms. Patients complained that they were unsatisfied due to the lack of disease and treatment information offered by the heath care team. In the process of adaptation, clinical features such as tumor location and treatment scheme are considered basic, as well as age, education, marital status. Areas such as sexuality, interpersonal and family relationships, economic status and emotional state of patients affected by the disease and treatments provide a deep complexity in the study of the psychosocial adaptation process in patients with CRC.

  11. Contrast-Induced Nephropathy in Patients Undergoing Percutaneous Coronary Intervention

    Sana Shoukat

    2010-01-01

    Full Text Available Contrast Induced Nephropathy (CIN is a feared complication of numerous radiological procedures that expose patients to contrast media. The most notorious of these procedures is percutaneous coronary intervention (PCI. Not only is this a leading cause of morbidity and mortality, but it also adds to increased costs in high risk patients undergoing PCI. It is thought to result from direct cytotoxicity and hemodynamic challenge to renal tissue. CIN is defined as an increase in serum creatinine by either ≥0.5 mg/dL or by ≥25% from baseline within the first 2-3 days after contrast administration, after other causes of renal impairment have been excluded. The incidence is considerably higher in diabetics, elderly and patients with pre-existing renal disease when compared to the general population. The nephrotoxic potential of various contrast agents must be evaluated completely, with prevention as the mainstay of focus as no effective treatment exists. The purpose of this article is to examine the pathophysiology, risk factors, and clinical course of CIN, as well as the most recent studies dealing with its prevention and potential therapeutic interventions, especially during PCI. The role of gadolinium as an alternative to iodinated contrast is also discussed.

  12. Plasma magnesium concentration in patients undergoing coronary artery bypass grafting.

    Kotlinska-Hasiec, Edyta; Makara-Studzinska, Marta; Czajkowski, Marek; Rzecki, Ziemowit; Olszewski, Krzysztof; Stadnik, Adam; Pilat, Jacek; Rybojad, Beata; Dabrowski, Wojciech

    2017-05-11

    [b]Introduction[/b]. Magnesium (Mg) plays a crucial role in cell physiology and its deficiency may cause many disorders which often require intensive treatment. The aim of this study was to analyse some factors affecting preoperative plasma Mg concentration in patients undergoing coronary artery bypass grafting (CABG). [b]Materials and method[/b]. Adult patients scheduled for elective CABG with cardio-pulmonary bypass (CPB) under general anaesthesia were studied. Plasma Mg concentration was analysed before surgery in accordance with age, domicile, profession, tobacco smoking and preoperative Mg supplementation. Blood samples were obtained from the radial artery just before the administration of anaesthesia. [b]Results. [/b]150 patients were studied. Mean preoperative plasma Mg concentration was 0.93 ± 0.17 mmol/L; mean concentration in patients - 1.02 ± 0.16; preoperative Mg supplementation was significantly higher than in patients without such supplementation. Moreover, intellectual workers supplemented Mg more frequently and had higher plasma Mg concentration than physical workers. Plasma Mg concentration decreases in elderly patients. Patients living in cities, on average, had the highest plasma Mg concentration. Smokers had significantly lower plasma Mg concentration than non-smokers. [b]Conclusions. [/b]1. Preoperative magnesium supplementation increases its plasma concentration. 2. Intellectual workers frequently supplement magnesium. 3. Smoking cigarettes decreases plasma magnesium concentration.

  13. Anxiety in Children Undergoing VCUG: Sedation or No Sedation?

    David W. Herd

    2008-01-01

    Full Text Available Background. Voiding cystourethrograms are distressing for children and parents. Nonpharmacological methods reduce distress. Pharmacological interventions for VCUG focus on sedation as well as analgesia, anxiolysis, and amnesia. Sedation has cost, time, and safety issues. Which agents and route should we use? Are we sure that sedation does not influence the ability to diagnose vesicoureteric reflux? Methods. Literature search of Medline, EMBASE, and the Cochrane Database. Review of comparative studies found. Results. Seven comparative studies including two randomised controlled trials were reviewed. Midazolam given orally (0.5-0.6 mg/kg or intranasally (0.2 mg/kg is effective with no apparent effect on voiding dynamics. Insufficient evidence to recommend other sedating agents was found. Deeper sedating agents may interfere with voiding dynamics. Conclusion. Midazolam reduces the VCUG distress, causes amnesia, and does not appear to interfere with voiding dynamics. Midazolam combined with simple analgesia is an effective method to reduce distress to children undergoing VCUG.

  14. Mediator Undergoes a Compositional Change during Transcriptional Activation.

    Petrenko, Natalia; Jin, Yi; Wong, Koon Ho; Struhl, Kevin

    2016-11-03

    Mediator is a transcriptional co-activator recruited to enhancers by DNA-binding activators, and it also interacts with RNA polymerase (Pol) II as part of the preinitiation complex (PIC). We demonstrate that a single Mediator complex associates with the enhancer and core promoter in vivo, indicating that it can physically bridge these transcriptional elements. However, the Mediator kinase module associates strongly with the enhancer, but not with the core promoter, and it dissociates from the enhancer upon depletion of the TFIIH kinase. Severing the kinase module from Mediator by removing the connecting subunit Med13 does not affect Mediator association at the core promoter but increases occupancy at enhancers. Thus, Mediator undergoes a compositional change in which the kinase module, recruited via Mediator to the enhancer, dissociates from Mediator to permit association with Pol II and the PIC. As such, Mediator acts as a dynamic bridge between the enhancer and core promoter. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Systemic scleroderma diagnosed after undergoing radiation therapy for breast cancer

    Sasaki, Tetsuo; Kakei, Masae

    1994-01-01

    A case of systemic scleroderma in which the symptoms became prominent after undergoing radiation therapy for breast cancer is reported. A 68-year-old woman, who had undergone a radical mastectomy for breast carcinoma at the age of 63 and thereafter received radiotherapy at 65, 66 and 67 years of age, visited our clinic complaining of skin sclerosis and Raynaud's phenomenon which she had noticed since the age of 65. The physical examination revealed not only postirradiation fibrosis and pigmentation, but also edematous sclerosis and the pigmentation of her extremities, as well as short frenulum of the tongue and digital pitting scars. She demonstrated serum anti-topoisomerase I antibodies, esophageal dysfunction and lung fibrosis. The histopathology of the forearm skin showed edema of the upper dermis as well as increased and homogenized collagen bundles in the middle and lower dermis. Since similar cases have been reported, it is considerable that radiation therapy may have thus worsened the lesions of scleroderma in this patient as well. (author)

  16. Systemic scleroderma diagnosed after undergoing radiation therapy for breast cancer

    Sasaki, Tetsuo; Kakei, Masae (Yokohama City Univ. (Japan). Faculty of Medicine)

    1994-10-01

    A case of systemic scleroderma in which the symptoms became prominent after undergoing radiation therapy for breast cancer is reported. A 68-year-old woman, who had undergone a radical mastectomy for breast carcinoma at the age of 63 and thereafter received radiotherapy at 65, 66 and 67 years of age, visited our clinic complaining of skin sclerosis and Raynaud's phenomenon which she had noticed since the age of 65. The physical examination revealed not only postirradiation fibrosis and pigmentation, but also edematous sclerosis and the pigmentation of her extremities, as well as short frenulum of the tongue and digital pitting scars. She demonstrated serum anti-topoisomerase I antibodies, esophageal dysfunction and lung fibrosis. The histopathology of the forearm skin showed edema of the upper dermis as well as increased and homogenized collagen bundles in the middle and lower dermis. Since similar cases have been reported, it is considerable that radiation therapy may have thus worsened the lesions of scleroderma in this patient as well. (author).

  17. Is Antibiotic Prophylaxis Necessary in Patients Undergoing Ureterolithotripsy?

    Ali Pasha Meysamie

    2011-08-01

    Full Text Available Transurethral Ureterolithotripsy (TUL is a frequently used procedure in urology departments. Many urologists perform TUL without antibiotic prophylaxis; however the use of chemoprophylaxis before TUL remains a controversial issue in urology. Thisstudy was carried out to assess the safety of omitting antibiotic prophylaxis prior to TUL. In a prospective randomized clinical trial from January 2005 to December 2007, 114 patients with ureteral stones were enrolled; Fifty seven had preoperative antibiotic prophylaxis administered before TUL and fifty seven patients underwent TUL without antibiotic prophylaxis. The rate of postoperative infectious complications (fever, positive blood culture, significant bactriuria, the length of hospital stay and overall stone free rate were compared between the two groups. There was no statistically significant difference between two groups in the operation time, length of hospital stay, postoperative bacteriuria, positive urine culture, postoperative fever and overall success rate of TUL. It appears that the incidence of infectious complications does not increase in patients undergoing TUL without antibiotic prophylaxis if they have negative pre-operative urine culture and antiseptic technique have been performed thorough the procedure.

  18. Analysis of corneal esthesia in patients undergoing photorefractive keratectomy

    Elmar Torres Neto

    2015-12-01

    Full Text Available ABSTRACT Purpose: To quantitatively analyze corneal esthesia in patients undergoing photorefractive keratectomy (PRK surgery. Methods: Forty-five patients selected for PRK in one eye underwent corneal esthesia using a Cochet-Bonnet esthesiometer preoperatively and 30 and 90 days postoperatively. Patients with a refractive diopter error of 4 or greater received intraoperative 0.02% mitomycin C for 20 s. Results: Twenty-four (53.3% of the 45 eyes received intraoperative 0.02% mitomycin. Decreased sensitivity was observed on postoperative day 30. By postoperative day 90, corneal esthesia had normalized but remained 14.9% lower than preoperative levels. In the mitomycin group, no recovery of corneal esthesia to normal sensitivity levels was observed. The mean esthesiometer level was 39.2 mm on postoperative day 90 (P<0.001. Conclusions: The results of the present study demonstrate recovery of corneal esthesia to normal levels at 90 days postoperatively in patients who did not receive mitomycin C. In patients administered mitomycin C, a 23.59% reduction in the corneal touch threshold was observed compared with preoperative levels indicating a failure of recovery to normal levels.

  19. Functional capacity and mental state of patients undergoing cardiac surgery

    Bruna Corrêa

    Full Text Available Abstract Introduction: Cardiovascular diseases are a serious public health problem in Brazil. Myocardial revascularization surgery (MRS as well as cardiac valve replacement and repair are procedures indicated to treat them. Thus, extracorporeal circulation (ECC is still widely used in these surgeries, in which patients with long ECC times may have greater neurological deficits. Neurological damage resulting from MRS can have devastating consequences such as loss of independence and worsening of quality of life. Objective: To assess the effect of cardiac surgery on a patient’s mental state and functional capacity in both the pre- and postoperative periods. Methods: We conducted a cross-sectional study with convenience sampling of subjects undergoing MRS and valve replacement. Participants were administered the Mini-Mental State Exam (MMSE and the Duke Activity Status Index (DASI in the pre- and postoperative periods, as well as before their hospital discharge. Results: This study assessed nine patients (eight males aged 62.4 ± 6.3 years with a BMI of 29.5 ± 2.3 kg/m2. There was a significant decrease in DASI scores and VO2 from preoperative to postoperative status (p = 0.003 and p = 0.003, respectively. Conclusion: This study revealed a loss of cognitive and exercise capacity after cardiac surgery. A larger sample however is needed to consolidate these findings.

  20. Antibody development in pediatric sickle cell patients undergoing erythrocytapheresis.

    Godfrey, Gwendolyn J; Lockwood, William; Kong, Maiying; Bertolone, Salvatore; Raj, Ashok

    2010-12-01

    Erythrocytapheresis, or red blood cell exchange transfusion (RBCX), with donor red blood cell (RBC) units is now increasingly used in the treatment of acute and chronic complications of sickle cell disease (SCD). As in all transfusions, RCBX carries a risk of immunization against foreign antigen on transfused cells. However, by selecting donor units with RBC phenotypes similar to the patient, the risk of allo- and autoimmunization can be reduced. The formation of RBC alloantibodies and/or autoantibodies in 32 multitransfused pediatric SCD patients undergoing monthly RBCX over a 11-year period (12/1998 to 12/2009) was evaluated utilizing a retrospective patient chart review at Kosair Children's Hospital, Louisville, Kentucky. After starting C, E, K antigen-matched RBCX, the rate of clinically significant allo-immunization decreased from 0.189/100 to 0.053/100 U, with a relative risk of 27.9%. Likewise, the rate of autoimmunization decreased from 0.063/100 to 0.035/100 U, with a relative risk of 55.9%. After controlling for clinically insignificant antibodies, our auto- and alloimmunization rate was much less than previously reported values. In addition, the incidence of clinically significant allo- and autoimmunization decreased in our patient population after starting minor antigen-matched RBCX. These results suggest that by matching selected RBC phenotypes, there may be an association in the risk of allo- and autoimmunization of multi-transfused SCD patients.

  1. Epidemiological evaluation of hepatic trauma victims undergoing surgery

    Mitre Kalil

    Full Text Available Objective : to evaluate the epidemiological variables and diagnostic and therapeutic modalities related to hepatic trauma patients undergoing laparotomy in a public referral hospital in the metropolitan region of Vitória-ES. Methods : we conducted a retrospective study, reviewing charts of trauma patients with liver injuries, whether isolated or in association with other organs, who underwent exploratory laparotomy, from January 2011 to December 2013. Results : We studied 392 patients, 107 of these with liver injury. The male: female ratio was 6.6 : 1 and the mean age was 30.12 years. Penetrating liver trauma occurred in 78.5% of patients, mostly with firearms. Associated injuries occurred in 86% of cases and intra-abdominal injuries were more common in penetrating trauma (p <0.01. The most commonly used operative technique was hepatorrhaphy and damage control surgery was applied in 6.5% of patients. The average amounts of blood products used were 6.07 units of packed red blood cells and 3.01 units of fresh frozen plasma. The incidence of postoperative complications was 29.9%, the most frequent being infectious, including pneumonia, peritonitis and intra-abdominal abscess. The survival rate of patients suffering from blunt trauma was 60%, and penetrating trauma, 87.5% (p <0.05. Conclusion : despite technological advances in diagnosis and treatment, mortality rates in liver trauma remain high, especially in patients suffering from blunt trauma in relation to penetrating one.

  2. Change of anxiety in patients undergoing coronary angiography

    Huang Zuo; Wu Zonggui; Wang Yongmei

    2004-01-01

    Objective: To investigate the change of anxiety in patients undergoing coronary angiography. Methods: The Spielberger State-Trait Anxiety Inventory was carried out in hundred and forty five patients, 104 men, 41 women, mean age (63 ± 9) years, before and after the coronary angiography procedure respectively. Results: The state anxiety score after the procedure was significantly decreased from 35.8 ± 10.2 to 31.7 ± 9.9 (P<0.01). The trait anxiety score after the procedure was slighytly lowered from 35.7 ± 8.8 to 34.4 ± 9.4 (P=0.019). Sub- group analysis showed that the state anxiety score in 55 patients with normal coronary artery was markedly decreased from 37.5 ± 10.5 to 28.8 ± 8.2 (P<0.01) while the state anxiety score in 90 patients with abnormal coronary artery was unchanged. The score in those patients with abnormal coronary artery was much higher than that of patients with normal coronary artery (33.5 ± 10.4 vs 28.8 ± 8.2, P<0.01). The trait anxiety scores in both group were not changed. Conclusion: Good news about normal coronary artery after angiography may reduce the anxiety in patients suspected of coronary heart disease. (authors)

  3. Constitutive Model Of Graded Micro-Structure Obtained Via Strain Induced Phase Transformation

    Ortwein, Rafał

    The literature review has been divided into three main sub-chapters. The first one is concentrated on the general information about stainless steels and their applications. It is important to perform a general overview and get an idea where the results of the present thesis could be applied. Description of all the brands of stainless steels, their microstructures and properties are important, as similar characteristics can be found in the newly created functionally graded structures. The second sub-chapter is an overview of the most important constitutive models and the experimental results for materials that undergo plastic strain induced phase transformation. Finally, the last one is devoted to functionally graded microstructures obtained via strain induced martensitic transformation – the subject of particular importance for the present thesis. As a general note, the literature review is organized mainly in a chronological order. In some cases similar publications or publications of the same Authors were...

  4. Epigenetics as an emerging tool for improvement of fungal strains used in biotechnology.

    Aghcheh, Razieh Karimi; Kubicek, Christian P

    2015-08-01

    Filamentous fungi are today a major source of industrial biotechnology for the production of primary and secondary metabolites, as well as enzymes and recombinant proteins. All of them have undergone extensive improvement strain programs, initially by classical mutagenesis and later on by genetic manipulation. Thereby, strategies to overcome rate-limiting or yield-reducing reactions included manipulating the expression of individual genes, their regulatory genes, and also their function. Yet, research of the last decade clearly showed that cells can also undergo heritable changes in gene expression that do not involve changes in the underlying DNA sequences (=epigenetics). This involves three levels of regulation: (i) DNA methylation, (ii) chromatin remodeling by histone modification, and (iii) RNA interference. The demonstration of the occurrence of these processes in fungal model organisms such as Aspergillus nidulans and Neurospora crassa has stimulated its recent investigation as a tool for strain improvement in industrially used fungi. This review describes the progress that has thereby been obtained.

  5. Predicting creep rupture from early strain data

    Holmstroem, Stefan; Auerkari, Pertti

    2009-01-01

    To extend creep life modelling from classical rupture modelling, a robust and effective parametric strain model has been developed. The model can reproduce with good accuracy all parts of the creep curve, economically utilising the available rupture models. The resulting combined model can also be used to predict rupture from the available strain data, and to further improve the rupture models. The methodology can utilise unfailed specimen data for life assessment at lower stress levels than what is possible from rupture data alone. Master curves for creep strain and rupture have been produced for oxygen-free phosphorus-doped (OFP) copper with a maximum testing time of 51,000 h. Values of time to specific strain at given stress (40-165 MPa) and temperature (125-350 deg. C) were fitted to the models in the strain range of 0.1-38%. With typical inhomogeneous multi-batch creep data, the combined strain and rupture modelling involves the steps of investigation of the data quality, extraction of elastic and creep strain response, rupture modelling, data set balancing and creep strain modelling. Finally, the master curves for strain and rupture are tested and validated for overall fitting efficiency. With the Wilshire equation as the basis for the rupture model, the strain model applies classical parametric principles with an Arrhenius type of thermal activation and a power law type of stress dependence for the strain rate. The strain model also assumes that the processes of primary and secondary creep can be reasonably correlated. The rupture model represents a clear improvement over previous models in the range of the test data. The creep strain information from interrupted and running tests were assessed together with the rupture data investigating the possibility of rupture model improvement towards lower stress levels by inverse utilisation of the combined rupture based strain model. The developed creep strain model together with the improved rupture model is

  6. Conduction band structure and electron mobility in uniaxially strained Si via externally applied strain in nanomembranes

    Chen Feng [Xi' an Jiaotong University, Xi' an, Shaanxi 710049 (China); Euaruksakul, Chanan; Himpsel, F J; Lagally, Max G [University of Wisconsin-Madison, Madison, WI 53706 (United States); Liu Zheng; Liu Feng, E-mail: lagally@engr.wisc.edu [University of Utah, Salt Lake City, UT 84112 (United States)

    2011-08-17

    Strain changes the band structure of semiconductors. We use x-ray absorption spectroscopy to study the change in the density of conduction band (CB) states when silicon is uniaxially strained along the [1 0 0] and [1 1 0] directions. High stress can be applied to silicon nanomembranes, because their thinness allows high levels of strain without fracture. Strain-induced changes in both the sixfold degenerate {Delta} valleys and the eightfold degenerate L valleys are determined quantitatively. The uniaxial deformation potentials of both {Delta} and L valleys are directly extracted using a strain tensor appropriate to the boundary conditions, i.e., confinement in the plane in the direction orthogonal to the straining direction, which correspond to those of strained CMOS in commercial applications. The experimentally determined deformation potentials match the theoretical predictions well. We predict electron mobility enhancement created by strain-induced CB modifications.

  7. Geographic variation in sexual attraction of Spodoptera frugiperda corn- and rice-strain males to pheromone lures.

    Melanie Unbehend

    Full Text Available The corn- and rice-strains of Spodoptera frugiperda exhibit several genetic and behavioral differences and appear to be undergoing ecological speciation in sympatry. Previous studies reported conflicting results when investigating male attraction to pheromone lures in different regions, but this could have been due to inter-strain and/or geographic differences. Therefore, we investigated whether corn- and rice-strain males differed in their response to different synthetic pheromone blends in different regions in North America, the Caribbean and South America. All trapped males were strain-typed by two strain-specific mitochondrial DNA markers. In the first experiment, we found a nearly similar response of corn- and rice-strain males to two different 4-component blends, resembling the corn- and rice-strain female blend we previously described from females in Florida. This response showed some geographic variation in fields in Canada, North Carolina, Florida, Puerto Rico, and South America (Peru, Argentina. In dose-response experiments with the critical secondary sex pheromone component (Z-7-dodecenyl acetate (Z7-12:OAc, we found some strain-specific differences in male attraction. While the response to Z7-12:OAc varied geographically in the corn-strain, rice-strain males showed almost no variation. We also found that the minor compound (Z-11-hexadecenyl acetate (Z11-16:OAc did not increase attraction of both strains in Florida and of corn-strain males in Peru. In a fourth experiment, where we added the stereo-isomer of the critical sex pheromone component, (E-7-dodecenyl acetate, to the major pheromone component (Z-9-tetradecenyl acetate (Z9-14:OAc, we found that this compound was attractive to males in North Carolina, but not to males in Peru. Overall, our results suggest that both strains show rather geographic than strain-specific differences in their response to pheromone lures, and that regional sexual communication differences might cause

  8. Nanocomposite Strain Gauges Having Small TCRs

    Gregory, Otto; Chen, Ximing

    2009-01-01

    Ceramic strain gauges in which the strain-sensitive electrically conductive strips made from nanocomposites of noble metal and indium tin oxide (ITO) are being developed for use in gas turbine engines and other power-generation systems in which gas temperatures can exceed 1,500 F (about 816 C). In general, strain gauges exhibit spurious thermally induced components of response denoted apparent strain. When temperature varies, a strain-gauge material that has a nonzero temperature coefficient of resistance (TCR) exhibits an undesired change in electrical resistance that can be mistaken for the change in resistance caused by a change in strain. It would be desirable to formulate straingauge materials having TCRs as small as possible so as to minimize apparent strain. Most metals exhibit positive TCRs, while most semiconductors, including ITO, exhibit negative TCRs. The present development is based on the idea of using the negative TCR of ITO to counter the positive TCRs of noble metals and of obtaining the benefit of the ability of both ITO and noble metals to endure high temperatures. The noble metal used in this development thus far has been platinum. Combinatorial libraries of many ceramic strain gauges containing nanocomposites of various proportions of ITO and platinum were fabricated by reactive co-sputtering from ITO and platinum targets onto alumina- and zirconia-based substrates mounted at various positions between the targets.

  9. Strain differentiation of polioviruses with monoclonal antibodies.

    A.D.M.E. Osterhaus (Albert); A.L. van Wezel; A.J.H. Stegmann; J.A.A.M. van Asten (Jack)

    1984-01-01

    textabstractPanels of monoclonal antibodies raised against different poliovirus type 1, 2 and 3 strains, were tested in a micro-neutralization test and in a micro-enzyme linked immunosorbent assay against a large number of poliovirus strains. The results were compared with those obtained with the

  10. Organic metabolites produced by Vibrio parahaemolyticus strain ...

    Identification and action of several antibacterial metabolites produced by a fish pathogen Vibrio parahaemolyticus strain An3 from marine ecosystem of Goa has been demonstrated. Antibacterial activity of the crude cell extract of the test bacterium has been evaluated against indicator pathogenic bacterial strains such as ...

  11. On lower order strain gradient plasticity theories

    Niordson, Christian Frithiof; Hutchinson, J. W.

    2002-01-01

    By way of numerical examples, this paper explores the nature of solutions to a class of strain gradient plasticity theories that employ conventional stresses, equilibrium equations and boundary conditions. Strain gradients come into play in these modified conventional theories only to alter...

  12. Job strain and time to pregnancy

    Hjollund, N H; Kold Jensen, T; Bonde, Jens Peter

    1998-01-01

    The association between fertility and job strain defined as high job demands and low job control has not previously been studied. A follow-up study was conducted with prospective collection of information on job strain among women, achievement of pregnancy, and potential confounding variables....

  13. Medically Complex Home Care and Caregiver Strain

    Moorman, Sara M.; Macdonald, Cameron

    2013-01-01

    Purpose of the study: To examine (a) whether the content of caregiving tasks (i.e., nursing vs. personal care) contributes to variation in caregivers' strain and (b) whether the level of complexity of nursing tasks contributes to variation in strain among caregivers providing help with such tasks. Design and methods: The data came from the Cash…

  14. Five challenges in modelling interacting strain dynamics

    Wikramaratna, Paul S; Kurcharski, Adam; Gupta, Sunetra

    2015-01-01

    population models. Next we consider the nature of so-called “strain space”. We describe two key types of host heterogeneities, and explain how models could help generate a better understanding of their effects. Finally, for diseases with many strains, we consider the challenge of modelling how immunity...

  15. Multiple Genome Sequences of Lactobacillus plantarum Strains

    Kafka, Thomas A.; Geissler, Andreas J.; Vogel, Rudi F.

    2017-01-01

    ABSTRACT We report here the genome sequences of four Lactobacillus plantarum strains which vary in surface hydrophobicity. Bioinformatic analysis, using additional genomes of Lactobacillus plantarum strains, revealed a possible correlation between the cell wall teichoic acid-type and cell surface hydrophobicity and provide the basis for consecutive analyses.

  16. Preliminary characterization of slow growing rhizobial strains ...

    In this paper, we did some preliminary characterization of six slow growing rhizobial strains, isolated from Retama monosperma (L.) Boiss. root nodules sampled from 3 sites along the coast of Oran (CapeFalcon, Bousfer and MersElHadjadj) in Northwestern Algeria. Results of this study showed that all strains had a very ...

  17. Typing of lymphogranuloma venereum Chlamydia trachomatis strains

    Christerson, Linus; de Vries, Henry J. C.; de Barbeyrac, Bertille; Gaydos, Charlotte A.; Henrich, Birgit; Hoffmann, Steen; Schachter, Julius; Thorvaldsen, Johannes; Vall-Mayans, Martí; Klint, Markus; Herrmann, Björn; Morré, Servaas A.

    2010-01-01

    We analyzed by multilocus sequence typing 77 lymphogranuloma venereum Chlamydia trachomatis strains from men who have sex with men in Europe and the United States. Specimens from an outbreak in 2003 in Europe were monoclonal. In contrast, several strains were in the United States in the 1980s,

  18. Typing of Lymphogranuloma Venereum Chlamydia trachomatis Strains

    Christerson, Linus; de Vries, Henry J.C.; de Barbeyrac, Bertille; Gaydos, Charlotte A.; Henrich, Birgit; Hoffmann, Steen; Schachter, Julius; Thorvaldsen, Johannes; Vall-Mayans, Martí; Klint, Markus; Morré, Servaas A.

    2010-01-01

    We analyzed by multilocus sequence typing 77 lymphogranuloma venereum Chlamydia trachomatis strains from men who have sex with men in Europe and the United States. Specimens from an outbreak in 2003 in Europe were monoclonal. In contrast, several strains were in the United States in the 1980s, including a variant from Europe. PMID:21029543

  19. MARSI: metabolite analogues for rational strain improvement

    Cardoso, João G. R.; Zeidan, Ahmad A; Jensen, Kristian

    2018-01-01

    reactions in an organism can be used to predict effects of MAs on cellular phenotypes. Here, we present the Metabolite Analogues for Rational Strain Improvement (MARSI) framework. MARSI provides a rational approach to strain improvement by searching for metabolites as targets instead of genes or reactions...

  20. General Strain Theory and Delinquency: Focusing on the Influences of Key Strain Characteristics on Delinquency

    Moon, Byongook; Blurton, David; McCluskey, John D.

    2008-01-01

    The study examines the effects of recent, older, and chronic strains and of perceived injustice of strain on delinquency, sampling 777 Korean youth. Seven key strains most likely leading to delinquency, some of which were often overlooked in previous research, were included, and these are family conflict, parental punishment, teachers' punishment,…

  1. Strain localization band width evolution by electronic speckle pattern interferometry strain rate measurement

    Guelorget, Bruno [Institut Charles Delaunay-LASMIS, Universite de technologie de Troyes, FRE CNRS 2848, 12 rue Marie Curie, B.P. 2060, 10010 Troyes Cedex (France)], E-mail: bruno.guelorget@utt.fr; Francois, Manuel; Montay, Guillaume [Institut Charles Delaunay-LASMIS, Universite de technologie de Troyes, FRE CNRS 2848, 12 rue Marie Curie, B.P. 2060, 10010 Troyes Cedex (France)

    2009-04-15

    In this paper, electronic speckle pattern interferometry strain rate measurements are used to quantify the width of the strain localization band, which occurs when a sheet specimen is submitted to tension. It is shown that the width of this band decreases with increasing strain. Just before fracture, this measured width is about five times wider than the shear band and the initial sheet thickness.

  2. Limitations of Hollomon and Ludwigson stress-strain relations in assessing the strain hardening parameters

    Samuel, K G

    2006-01-01

    It is shown that the deviation from the ideal Hollomon relation in describing the stress-strain behaviour is characteristic of all materials at low strains. The Ludwigson relation describing the deviation from the Hollomon relation at low strains is critically analysed and it is shown that the deviation at low strains is a consequence of some unknown 'plastic strain equivalent' present in the material. Stress strain curves obeying an ideal Hollomon relation as well as that of a structurally modified (prior cold worked) material were simulated and compared. The results show that the yield strength and the flow strength of a material at constant strain rate and temperature are dictated by the magnitude of the 'plastic strain equivalent' term. It is shown that this component need not necessarily mean a prior plastic strain present in the material due to prior cold work alone and that prior cold work strain will add to this. If this component is identified, the stress-strain behaviour can be adequately described by the Swift relation. It is shown that in both formalisms, the strain hardening index is a function of the yield strength of the material

  3. Radiation Dose Estimation for Pediatric Patients Undergoing Cardiac Catheterization

    Wang, Chu

    Patients undergoing cardiac catheterization are potentially at risk of radiation-induced health effects from the interventional fluoroscopic X-ray imaging used throughout the clinical procedure. The amount of radiation exposure is highly dependent on the complexity of the procedure and the level of optimization in imaging parameters applied by the clinician. For cardiac catheterization, patient radiation dosimetry, for key organs as well as whole-body effective, is challenging due to the lack of fixed imaging protocols, unlike other common X-ray based imaging modalities. Pediatric patients are at a greater risk compared to adults due to their greater cellular radio-sensitivities as well as longer remaining life-expectancy following the radiation exposure. In terms of radiation dosimetry, they are often more challenging due to greater variation in body size, which often triggers a wider range of imaging parameters in modern imaging systems with automatic dose rate modulation. The overall objective of this dissertation was to develop a comprehensive method of radiation dose estimation for pediatric patients undergoing cardiac catheterization. In this dissertation, the research is divided into two main parts: the Physics Component and the Clinical Component. A proof-of-principle study focused on two patient age groups (Newborn and Five-year-old), one popular biplane imaging system, and the clinical practice of two pediatric cardiologists at one large academic medical center. The Physics Component includes experiments relevant to the physical measurement of patient organ dose using high-sensitivity MOSFET dosimeters placed in anthropomorphic pediatric phantoms. First, the three-dimensional angular dependence of MOSFET detectors in scatter medium under fluoroscopic irradiation was characterized. A custom-made spherical scatter phantom was used to measure response variations in three-dimensional angular orientations. The results were to be used as angular dependence

  4. The Effects of Partial Turbinectomy on Patients Undergoing Rhinoplasty

    Behrooz Gandomi

    2011-03-01

    Full Text Available Introduction: A reduction or cessation of the ability to breathe through the nose can affect a person's overall health. Nasal passage blockage can also result in snoring. Difficulty in breathing through the nose after rhinoplasty is a serious problem and patient dissatisfaction can be significant even when cosmetic results are excellent. Long-term impacts on the quality of life and contributions to the pathophysiology of sleep-related breathing disorders have both been documented. This study compares nasal obstruction and other prevalent respiratory side effects of rhinoplasty in the presence and absence of partial turbinectomy. Methods and Materials: This is an experimental case study conducted in 2007 on patients undergoing rhinoplastic surgery in Shahid Dastgheyb Hospital of Shiraz, Iran. Sampling was done on all admitted patients during this year in the mentioned hospital. For the first group, rhinoplasty plus partial turbinectomy was performed while taking into consideration the Helsinki criteria septorhinoplasty without partial turbinectomy was performed on the second group. P-value less than 0.05 was considered as statistically significant. Results: There was no significant difference between the case and control group in terms of their mean age and gender distribution. Respiratory mean scores before and after rhinoplasty in both groups were significantly different in some issues of Nasal Scale (i.e.: Nasal blockage or obstruction, trouble sleeping, inability to get enough air through the nose during exercise or exertion, trouble breathing through nose.  Conclusion: Achieving cosmetic goals while preserving such necessary functions is a great concern for rhinologists and this makes different complexes. To create a balance between the maximum physiologic function and the best cosmetic feature is an art.

  5. SERUM ELECTROLYTES AND OUTCOME IN PATIENTS UNDERGOING ENDOSCOPIC GASTROSTOMY

    Joana VIEIRA

    Full Text Available ABSTRACT BACKGROUND: Percutaneous endoscopic gastrostomy (PEG is a gold standard for long term enteral feeding. Neurologic dysphagia and head/neck cancer are the most common indications for PEG as they can lead to protein-energy malnutrition and serum electrolyte abnormalities, with potential negative impact on metabolic balance. Refeeding syndrome may also be related with severe electrolyte changes in PEG-fed patients and contribute to poor prognosis. OBJECTIVE: This study aims to evaluate the changes in serum concentrations of the main electrolytes and its possible association with the outcome. METHODS: Retrospective study of patients followed in our Artificial Nutrition Clinic, submitted to PEG from 2010 to 2016, having head/neck cancer or neurologic dysphagia, who died under PEG feeding. Serum electrolytes (sodium, potassium, chlorine, magnesium, calcium and phosphorus were evaluated immediately before the gastrostomy procedure. Survival after PEG until death was recorded in months. RESULTS: We evaluated 101 patients, 59 with electrolyte alterations at the moment of the gastrostomy. Sodium was altered in 32 (31.7%, magnesium in 21 (20.8%, chlorine in 21 (20.8%, potassium in 14 (13.8%, calcium in 11 (10.9 % and phosphorus in 11 (10.9%. The survival of patients with low sodium (<135 mmol/L was significantly lower when compared to patients with normal/high values, 2.76 months vs 7.80 months, respectively (P=0.007. CONCLUSION: Changes in serum electrolytes of patients undergoing PEG were very common. More than half showed at least one abnormality, at the time of the procedure. The most frequent was hyponatremia, which was associated with significantly shorter survival, probably reflecting severe systemic metabolic distress.

  6. Outcomes in Diabetic Patients Undergoing Orbital Atherectomy System.

    Lee, Michael S; Shlofmitz, Evan; Nguyen, Heajung; Shlofmitz, Richard A

    2016-10-01

    We evaluated the angiographic and clinical outcomes of orbital atherectomy to treat severely calcified coronary lesions in diabetic and non-diabetic patients. Diabetics have increased risk for death, myocardial infarction, and target vessel revascularization after percutaneous coronary intervention. Severely calcified coronary lesions are associated with increased cardiac events. Orbital atherectomy facilitates stent delivery and optimizes stent expansion by modifying severely calcified plaque. Outcomes in diabetic patients who undergo orbital atherectomy have not been reported. Our retrospective multicenter registry included 458 consecutive real-world patients with severely calcified coronary arteries who underwent orbital atherectomy. The primary safety endpoint was the rate of major adverse cardiac and cerebrovascular events at 30 days. Diabetics represented 42.1% (193/458) of the entire cohort. The primary endpoint was similar in diabetics and non-diabetics (1.0% vs. 3.0%%, P = 0.20), as were 30-day rates of death (0.5% vs. 1.9%, P = 0.41), myocardial infarction (0.5% vs. 1.5%, P = 0.40), target vessel revascularization (0% vs. 0%, P = 1), and stroke (0% vs. 0.4%, P > 0.9). Angiographic complications and stent thrombosis rate were low and did not differ between the 2 groups. Diabetics represented a sizeable portion of patients who underwent orbital atherectomy. Diabetics who had severely calcified coronary arteries and underwent orbital atherectomy had low event rates that were similar to non-diabetics. Orbital atherectomy appears to be a viable treatment strategy for diabetic patients. Randomized trials with longer-term follow-up are needed to determine the ideal treatment strategy for diabetics. © 2016, Wiley Periodicals, Inc.

  7. Fatigue and Oxidative Stress in Children Undergoing Leukemia Treatment.

    Rodgers, Cheryl; Sanborn, Chelse; Taylor, Olga; Gundy, Patricia; Pasvogel, Alice; Moore, Ida M Ki; Hockenberry, Marilyn J

    2016-10-01

    Fatigue is a frequent and distressing symptom in children undergoing leukemia treatment; however, little is known about factors influencing this symptom. Antioxidants such as glutathione can decrease symptom severity in adult oncology patients, but no study has evaluated antioxidants' effects on symptoms in pediatric oncology patients. This study describes fatigue patterns and associations of fatigue with antioxidants represented by reduced glutathione (GSH) and the reduced/oxidized glutathione (GSH/GSSG) ratio among children receiving leukemia treatment. A repeated measures design assessed fatigue and antioxidants among 38 children from two large U.S. cancer centers. Fatigue was assessed among school-age children and by parent proxy among young children. Antioxidants (GSH and GSH/GSSG ratio) were assessed from cerebrospinal fluid at four phases during leukemia treatment. Young children had a steady decline of fatigue from the end of induction treatment through the continuation phase of treatment, but no significant changes were noted among the school-age children. Mean antioxidant scores varied slightly over time; however, the GSH/GSSG ratios in these children were significantly lower than the normal ratio. Mean GSH/GSSG ratios significantly correlated to fatigue scores of the school-age children during early phases of treatment. Children with low mean GSH/GSSG ratios demonstrated oxidative stress. The low ratios noted early in therapy were significantly correlated with higher fatigue scores during induction and postinduction treatment phases. This finding suggests that increased oxidative stress during the more intensive phases of therapy may explain the experience of fatigue children report. © The Author(s) 2016.

  8. Analysis of ecological thresholds in a temperate forest undergoing dieback.

    Philip Martin

    Full Text Available Positive feedbacks in drivers of degradation can cause threshold responses in natural ecosystems. Though threshold responses have received much attention in studies of aquatic ecosystems, they have been neglected in terrestrial systems, such as forests, where the long time-scales required for monitoring have impeded research. In this study we explored the role of positive feedbacks in a temperate forest that has been monitored for 50 years and is undergoing dieback, largely as a result of death of the canopy dominant species (Fagus sylvatica, beech. Statistical analyses showed strong non-linear losses in basal area for some plots, while others showed relatively gradual change. Beech seedling density was positively related to canopy openness, but a similar relationship was not observed for saplings, suggesting a feedback whereby mortality in areas with high canopy openness was elevated. We combined this observation with empirical data on size- and growth-mediated mortality of trees to produce an individual-based model of forest dynamics. We used this model to simulate changes in the structure of the forest over 100 years under scenarios with different juvenile and mature mortality probabilities, as well as a positive feedback between seedling and mature tree mortality. This model produced declines in forest basal area when critical juvenile and mature mortality probabilities were exceeded. Feedbacks in juvenile mortality caused a greater reduction in basal area relative to scenarios with no feedback. Non-linear, concave declines of basal area occurred only when mature tree mortality was 3-5 times higher than rates observed in the field. Our results indicate that the longevity of trees may help to buffer forests against environmental change and that the maintenance of old, large trees may aid the resilience of forest stands. In addition, our work suggests that dieback of forests may be avoidable providing pressures on mature and juvenile trees do

  9. Radiation dose and cancer risk to children undergoing skull radiography

    Mazonakis, Michael; Damilakis, John; Raissaki, Maria; Gourtsoyiannis, Nicholas

    2004-01-01

    Background: Limited data exist in the literature concerning the patient-effective dose from paediatric skull radiography. No information has been provided regarding organ doses, patient dose during PA skull projection, risk of cancer induction and dose to comforters, i.e. individuals supporting children during exposure. Objective: To estimate patient-effective dose, organ doses, lifetime cancer mortality risk to children and radiation dose to comforters associated with skull radiography. Materials and methods: Data were collected from 136 paediatric examinations, including AP, PA and lateral skull radiographs. Entrance-surface dose (ESD) and dose to comforters were measured using thermoluminescent dosimeters. Patients were divided into the following age groups: 0.5-2, 3-7, 8-12 and 13-18 years. The patient-effective dose and corresponding organ doses were calculated using data from the NRPB and Monte Carlo techniques. The risk for fatal cancer induction was assessed using appropriate risk coefficients. Results: For AP, PA and lateral skull radiography, effective dose ranges were 8.8-25.4, 8.2-27.3 and 8.4-22.7 μSv respectively, depending upon the age of the child. For each skull projection, the organs receiving doses above 10 μGy are presented. The number of fatal cancers was found to be less than or equal to 2 per 1 million children undergoing a skull radiograph. The mean radiation dose absorbed by the hands of comforters was 13.4 μGy. Conclusions: The current study provides detailed tabular and graphical data on ESD, effective dose, organ doses and lifetime cancer mortality risk to children associated with AP, PA and lateral skull projections at all patient ages. (orig.)

  10. Survival benefit needed to undergo chemotherapy: Patient and physician preferences.

    Vaz-Luis, Ines; O'Neill, Anne; Sepucha, Karen; Miller, Kathy D; Baker, Emily; Dang, Chau T; Northfelt, Donald W; Winer, Eric P; Sledge, George W; Schneider, Bryan; Partridge, Ann H

    2017-08-01

    Published studies have suggested that most patients with early stage breast cancer are willing, for modest survival benefits, to receive 6 months of adjuvant cyclophosphamide, methotrexate, and 5-fluorouracil, an older regimen that is used infrequently today. We examined preferences regarding the survival benefit needed to justify 6 months of a contemporary chemotherapy regimen. The Eastern Cooperative Oncology Group Protocol 5103 was a phase 3 trial that randomized breast cancer patients to receive standard adjuvant doxorubicin, cyclophosphamide, and paclitaxel with either bevacizumab or placebo. Serial surveys to assess quality of life were administered to patients enrolled between January 1, 2010, and June 8, 2010. Survival benefit needed to justify 6 months of chemotherapy by patients was collected at the 18-month assessment. A parallel survey was sent to physicians who had enrolled patients in the study. Of 519 patients who had not withdrawn at a time point earlier than 18 months, 87.8% responded to this survey. A total of 175 physicians participated. We found considerable variation in patient preferences, particularly for modest survival benefits: for 2 months of benefit, 57% would consider 6 months of chemotherapy, whereas 96% of patients would consider 6 months of chemotherapy for 24 months. Race and education were associated with the choices. Physicians who responded were less likely to accept chemotherapy for modest benefit. Among patients who received contemporary adjuvant chemotherapy in a randomized controlled trial, we found substantial variation in preferences regarding benefits that justified undergoing chemotherapy. Differences between patients' and physicians' choices were also apparent. Eliciting preferences regarding risks and benefits of adjuvant chemotherapy is critical. Cancer 2017;123:2821-28. © 2017 American Cancer Society. © 2017 American Cancer Society.

  11. Pulsed photothermal depth profiling of tattoos undergoing laser removal treatment

    Milanic, Matija; Majaron, Boris

    2012-02-01

    Pulsed photothermal radiometry (PPTR) allows noninvasive determination of temperature depth profiles induced by pulsed laser irradiation of strongly scattering biological tissues and organs, including human skin. In present study, we evaluate the potential of this technique for investigational characterization and possibly quantitative evaluation of laser tattoo removal. The study involved 5 healthy volunteers (3 males, 2 females), age 20-30 years, undergoing tattoo removal treatment using a Q-switched Nd:YAG laser. There were four measurement and treatment sessions in total, separated by 2-3 months. Prior to each treatment, PPTR measurements were performed on several tattoo sites and one nearby healthy site in each patient, using a 5 ms Nd:YAG laser at low radiant exposure values and a dedicated radiometric setup. The laser-induced temperature profiles were then reconstructed by applying a custom numerical code. In addition, each tatoo site was documented with a digital camera and measured with a custom colorimetric system (in tristimulus color space), providing an objective evaluation of the therapeutic efficacy to be correlated with our PPTR results. The results show that the laser-induced temperature profile in untreated tattoos is invariably located at a subsurface depth of 300 μm. In tattoo sites that responded well to laser therapy, a significant drop of the temperature peak was observed in the profiles obtained from PPTR record. In several sites that appeared less responsive, as evidenced by colorimetric data, a progressive shift of the temperature profile deeper into the dermis was observed over the course of consecutive laser treatments, indicating that the laser tattoo removal was efficient.

  12. Coal in sub-Saharan-African countries undergoing desertification

    Weaver, J.N.; Brownfield, M.E.; Bergin, M.J. (United States Geological Survey, Denver, CO (USA))

    1990-01-01

    Coal has been reported in 11 of the 16 sub-Saharan countries discussed in this appraisal: Mauritania, Senegal, Mali, Niger, Benin, Nigeria, Cameroon, Central African Republic, Sudan, Ethiopia, and Somalia. No coal occurrences have been reported in Gambia, Togo, Burkina, Chad, and Djibouti but coal may be present within these countries because neighbouring countries do contain coal-bearing rocks. Most of these countries are undergoing desertification. Destruction of forest and shrub lands for fuel is occurring at an increasing rate because of desertification and increasing energy demands. Part of the present and future energy needs of the sub-Saharan region could be met by use of indigenous coal and peat. Nine sedimentary basins have the potential of either coal and/or peat deposits of economic value: 1- Senegal Basin, 2- Taoudeni Basin and Gao Trough, 3- Niger Basin, 4- Chad Basin. 5- Chari Basin, 6- Benue Trough (Depression), 7- Sudan Trough, 8- Plateau and Rift Belt, and 9- Somali Basin. Niger and Nigeria are the only countries in sub-Saharan Africa in which coal is presently being mined as a fuel source for powerplants and domestic use. Peat occurs in the deltas, lower river, and interdunal basin areas of Senegal, Mauritania, and Sudan. The overall objective of these studies is to establish, within the sub-Saharan region, energy independent countries using indigeneous coal and peat resources. These resources have the potential to replace wood and wood charcoal as domestic fuel in the urban centres, as well as producing electrical and industrial energy, thus reducing expensive oil imports and decreasing the rate of deforestation. 31 refs., 16 figs., 1 tab.

  13. Dizziness and Falls in Obese Inpatients Undergoing Metabolic Rehabilitation.

    Stefano Corna

    Full Text Available The relationship between dizziness and falls in the obese population is a relatively unexplored issue. The aims of the present study were to define the 1-year prevalence of dizziness in an obese inpatient population undergoing metabolic rehabilitation and to investigate possible correlations with fall events.We recruited 329 obese subjects: 203 female (BMI 43,74 kg/m2 ± 0.5 SE; age 17-83 years, 58.33 ± 0.9 SE and 126 male (BMI 44,27kg/m2 ± 0.7 DE age 27-79 years, 58.84 ± 1 SE. To assess dizziness we used the validated Italian version (38 of the Dizziness Handicap Inventory (DHI.Out of the experimental sample, 100 subjects did not complain of dizziness and felt confident about their balance control, while 69.6% reported some degree of dizziness. Their mean DHI score was 22.3, which corresponds to mild dizziness. Twenty-one percent reported more severe dizziness (DHI score > 40. The majority of our sample reported minor dizziness and its perception appears to be independent from BMI: DHI scores were consistent across classes of obesity.The rate of dizziness and falls (30.1% in an this obese population was higher than that previously reported in a general matched population. However, obese subjects, in our sample, seem to underestimate their risk of fall and DHI score does not appear a reliable predictor of falls. Since complications associated with falls in obese persons generally require longer treatments than in lean individuals, our findings should be taken into account in order to identify other predictors, including cognitive and perceptual, of risk of fall and to implement fall prevention programs.

  14. Incidence of bacteremia in cirrhotic patients undergoing upper endoscopic ultrasonography.

    Fernández-Esparrach, Gloria; Sendino, Oriol; Araujo, Isis; Pellisé, Maria; Almela, Manel; González-Suárez, Begoña; López-Cerón, María; Córdova, Henry; Sanabria, Erwin; Uchima, Hugo; Llach, Josep; Ginès, Àngels

    2014-01-01

    The incidence of bacteremia after endoscopic ultrasonography (EUS) or EUS-guided fine-needle aspiration (EUS-FNA) is between 0% and 4%, but there are no data on this topic in cirrhotic patients. To prospectively assess the incidence of bacteremia in cirrhotic patients undergoing EUS and EUS-FNA. We enrolled 41 cirrhotic patients. Of these, 16 (39%) also underwent EUS-FNA. Blood cultures were obtained before and at 5 and 30 min after the procedure. When EUS-FNA was used, an extra blood culture was obtained after the conclusion of radial EUS and before the introduction of the sectorial echoendoscope. All patients were clinically followed up for 7 days for signs of infection. Blood cultures were positive in 16 patients. In 10 patients, blood cultures grew coagulase-negative Staphylococcus, Corynebacterium species, Propionibacterium species or Acinetobacterium Lwoffii, which were considered contaminants (contamination rate 9.8%, 95% CI: 5.7-16%). The remaining 6 patients had true positive blood cultures and were considered to have had true bacteremia (15%, 95% CI: 4-26%). Blood cultures were positive after diagnostic EUS in five patients but were positive after EUS-FNA in only one patient. Thus, the frequency of bacteremia after EUS and EUS-FNA was 12% and 6%, respectively (95% CI: 2-22% and 0.2-30%, respectively). Only one of the patients who developed bacteremia after EUS had a self-limiting fever with no other signs of infection. Asymptomatic Gram-positive bacteremia developed in cirrhotic patients after EUS and EUS-FNA at a rate higher than in non-cirrhotic patients. However, this finding was not associated with any clinically significant infections. Copyright © 2013 Elsevier España, S.L. and AEEH y AEG. All rights reserved.

  15. Adenoma detection in patients undergoing a comprehensive colonoscopy screening

    Raju, Gottumukkala S; Vadyala, Vikram; Slack, Rebecca; Krishna, Somashekar G; Ross, William A; Lynch, Patrick M; Bresalier, Robert S; Hawk, Ernest; Stroehlein, John R

    2013-01-01

    Measures shown to improve the adenoma detection during colonoscopy (excellent bowel preparation, cecal intubation, cap fitted colonoscope to examine behind folds, patient position change to optimize colon distention, trained endoscopy team focusing on detection of subtle flat lesions, and incorporation of optimum endoscopic examination with adequate withdrawal time) are applicable to clinical practice and, if incorporated are projected to facilitate comprehensive colonoscopy screening program for colon cancer prevention. To determine adenoma and serrated polyp detection rate under conditions designed to optimize quality parameters for comprehensive screening colonoscopy. Retrospective analysis of data obtained from a comprehensive colon cancer screening program designed to optimize quality parameters. Academic medical center. Three hundred and forty-three patients between the ages of 50 years and 75 years who underwent first screening colonoscopy between 2009 and 2011 among 535 consecutive patients undergoing colonoscopy. Comprehensive colonoscopy screening program was utilized to screen all patients. Cecal intubation was successful in 98.8% of patients. The Boston Bowel Preparation Scale for quality of colonoscopy was 8.97 (95% confidence interval [CI]; 8.94, 9.00). The rate of adenoma detection was 60% and serrated lesion (defined as serrated adenomas or hyperplastic polyps proximal to the splenic flexure) detection was 23%. The rate of precancerous lesion detection (adenomas and serrated lesions) was 66%. The mean number of adenomas per screening procedure was 1.4 (1.2, 1.6) and the mean number of precancerous lesions (adenomas or serrated lesions) per screening procedure was 1.6 (1.4, 1.8). Retrospective study and single endoscopist experience. A comprehensive colonoscopy screening program results in high-quality screening with high detection of adenomas, advanced adenomas, serrated adenomas, and multiple adenomas

  16. Androgens (dehydroepiandrosterone or testosterone) for women undergoing assisted reproduction.

    Nagels, Helen E; Rishworth, Josephine R; Siristatidis, Charalampos S; Kroon, Ben

    2015-11-26

    Infertility is a condition affecting 10% to 15% of couples of reproductive age. It is generally defined as "the failure to achieve a clinical pregnancy after 12 months or more of regular unprotected sexual intercourse". The treatment of infertility may involve manipulation of gametes or of the embryos themselves. These techniques are together known as assisted reproductive technology (ART). Practitioners are constantly seeking alternative or adjunct treatments, or both, in the hope that they may improve the outcome of assisted reproductive techniques. This Cochrane review focusses on the adjunct use of synthetic versions of two naturally-produced hormones, dehydroepiandrosterone (DHEA) and testosterone (T), in assisted reproduction.DHEA and its derivative testosterone are steroid hormones proposed to increase conception rates by positively affecting follicular response to gonadotrophin stimulation, leading to greater oocyte yields and, in turn, increased chance of pregnancy. To assess the effectiveness and safety of DHEA and testosterone as pre- or co-treatments in subfertile women undergoing assisted reproduction. We searched the following electronic databases, trial registers and websites up to 12 March 2015: the Cochrane Central Register of Controlled Trials (CENTRAL), the Menstrual Disorders and Subfertility Group (MDSG) Specialised Register, MEDLINE, EMBASE, PsycINFO, CINAHL, electronic trial registers for ongoing and registered trials, citation indexes, conference abstracts in the Web of Science, PubMed and OpenSIGLE. We also carried out handsearches. There were no language restrictions. We included randomised controlled trials (RCTs) comparing DHEA or testosterone as an adjunct treatment to any other active intervention, placebo, or no treatment in women undergoing assisted reproduction. Two review authors independently selected studies, extracted relevant data and assessed them for risk of bias. We pooled studies using fixed-effect models. We calculated

  17. Red blood cell transfusion for people undergoing hip fracture surgery.

    Brunskill, Susan J; Millette, Sarah L; Shokoohi, Ali; Pulford, E C; Doree, Carolyn; Murphy, Michael F; Stanworth, Simon

    2015-04-21

    The incidence of hip fracture is increasing and it is more common with increasing age. Surgery is used for almost all hip fractures. Blood loss occurs as a consequence of both the fracture and the surgery and thus red blood cell transfusion is frequently used. However, red blood cell transfusion is not without risks. Therefore, it is important to identify the evidence for the effective and safe use of red blood cell transfusion in people with hip fracture. To assess the effects (benefits and harms) of red blood cell transfusion in people undergoing surgery for hip fracture. We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (31 October 2014), the Cochrane Central Register of Controlled Trials (The Cochrane Library, 2014, Issue 10), MEDLINE (January 1946 to 20 November 2014), EMBASE (January 1974 to 20 November 2014), CINAHL (January 1982 to 20 November 2014), British Nursing Index Database (January 1992 to 20 November 2014), the Systematic Review Initiative's Transfusion Evidence Library, PubMed for e-publications, various other databases and ongoing trial registers. Randomised controlled trials comparing red blood cell transfusion versus no transfusion or an alternative to transfusion, different transfusion protocols or different transfusion thresholds in people undergoing surgery for hip fracture. Three review authors independently assessed each study's risk of bias and extracted data using a study-specific form. We pooled data where there was homogeneity in the trial comparisons and the timing of outcome measurement. We used GRADE criteria to assess the quality (low, moderate or high) of the evidence for each outcome. We included six trials (2722 participants): all compared two thresholds for red blood cell transfusion: a 'liberal' strategy to maintain a haemoglobin concentration of usually 10 g/dL versus a more 'restrictive' strategy based on symptoms of anaemia or a lower haemoglobin concentration, usually 8 g/dL. The exact

  18. Atlas of stress-strain curves

    2002-01-01

    The Atlas of Stress-Strain Curves, Second Edition is substantially bigger in page dimensions, number of pages, and total number of curves than the previous edition. It contains over 1,400 curves, almost three times as many as in the 1987 edition. The curves are normalized in appearance to aid making comparisons among materials. All diagrams include metric (SI) units, and many also include U.S. customary units. All curves are captioned in a consistent format with valuable information including (as available) standard designation, the primary source of the curve, mechanical properties (including hardening exponent and strength coefficient), condition of sample, strain rate, test temperature, and alloy composition. Curve types include monotonic and cyclic stress-strain, isochronous stress-strain, and tangent modulus. Curves are logically arranged and indexed for fast retrieval of information. The book also includes an introduction that provides background information on methods of stress-strain determination, on...

  19. [New antibiotics produced by Bacillus subtilis strains].

    Malanicheva, I A; Kozlov, D G; Efimenko, T A; Zenkova, V A; Kastrukha, G S; Reznikova, M I; Korolev, A M; Borshchevskaia, L N; Tarasova, O D; Sineokiĭ, S P; Efremenkova, O V

    2014-01-01

    Two Bacillus subtilis strains isolated from the fruiting body of a basidiomycete fungus Pholiota squarrosa exhibited a broad range of antibacterial activity, including those against methicillin-resistant Staphylococcus aureus INA 00761 (MRSA) and Leuconostoc mes6nteroides VKPM B-4177 resistant to glycopep-> tide antibiotics, as well as antifungal activity. The strains were identified as belonging to the "B. subtilis" com- plex based on their morphological and physiological characteristics, as well as by sequencing of the 16S rRNA gene fragments. Both strains (INA 01085 and INA 01086) produced insignificant amounts of polyene antibiotics (hexaen and pentaen, respectively). Strain INA 01086 produced also a cyclic polypeptide antibiotic containing Asp, Gly, Leu, Pro, Tyr, Thr, Trp, and Phe, while the antibiotic of strain INA 01085 contained, apart from these, two unidentified nonproteinaceous amino acids. Both polypeptide antibiotics were new compounds efficient against gram-positive bacteria and able to override the natural bacterial antibiotic resistance.

  20. On fracture in finite strain gradient plasticity

    Martínez Pañeda, Emilio; Niordson, Christian Frithiof

    2016-01-01

    In this work a general framework for damage and fracture assessment including the effect of strain gradients is provided. Both mechanism-based and phenomenological strain gradient plasticity (SGP) theories are implemented numerically using finite deformation theory and crack tip fields are invest......In this work a general framework for damage and fracture assessment including the effect of strain gradients is provided. Both mechanism-based and phenomenological strain gradient plasticity (SGP) theories are implemented numerically using finite deformation theory and crack tip fields...... are investigated. Differences and similarities between the two approaches within continuum SGP modeling are highlighted and discussed. Local strain hardening promoted by geometrically necessary dislocations (GNDs) in the vicinity of the crack leads to much higher stresses, relative to classical plasticity...... in the multiple parameter version of the phenomenological SGP theory. Since this also dominates the mechanics of indentation testing, results suggest that length parameters characteristic of mode I fracture should be inferred from nanoindentation....

  1. Dark field electron holography for strain measurement

    Beche, A., E-mail: armand.beche@fei.com [CEA-Grenoble, INAC/SP2M/LEMMA, F-38054 Grenoble (France); Rouviere, J.L. [CEA-Grenoble, INAC/SP2M/LEMMA, F-38054 Grenoble (France); Barnes, J.P.; Cooper, D. [CEA-LETI, Minatec Campus, F-38054 Grenoble (France)

    2011-02-15

    Dark field electron holography is a new TEM-based technique for measuring strain with nanometer scale resolution. Here we present the procedure to align a transmission electron microscope and obtain dark field holograms as well as the theoretical background necessary to reconstruct strain maps from holograms. A series of experimental parameters such as biprism voltage, sample thickness, exposure time, tilt angle and choice of diffracted beam are then investigated on a silicon-germanium layer epitaxially embedded in a silicon matrix in order to obtain optimal dark field holograms over a large field of view with good spatial resolution and strain sensitivity. -- Research Highlights: {yields} Step by step explanation of the dark field electron holography technique. {yields} Presentation of the theoretical equations to obtain quantitative strain map. {yields} Description of experimental parameters influencing dark field holography results. {yields} Quantitative strain measurement on a SiGe layer embedded in a silicon matrix.

  2. Pseudomagnetic fields and triaxial strain in graphene

    Settnes, Mikkel; Power, Stephen; Jauho, Antti-Pekka

    2016-01-01

    Pseudomagnetic fields, which can result from nonuniform strain distributions, have received much attention in graphene systems due to the possibility of mimicking real magnetic fields with magnitudes of greater than 100 T. We examine systems with such strains confined to finite regions ("pseudoma......Pseudomagnetic fields, which can result from nonuniform strain distributions, have received much attention in graphene systems due to the possibility of mimicking real magnetic fields with magnitudes of greater than 100 T. We examine systems with such strains confined to finite regions......-binding calculations of single pseudomagnetic dots in extended graphene sheets confirm these predictions, and are also used to study the effect of rotating the strain direction with respect to the underlying graphene lattice, and varying the size of the pseudomagnetic dot....

  3. MODERNIZATION OF GENEOTIPING OF STRAINS B. PERTUSSIS

    G. A. Ivashinnikova

    2013-01-01

    Full Text Available The new rapid molecular genotyping method was developed for studying the structure of ptxP promoter of pertussis toxin. Method is based on PCR-RFLP analysis, which allows studying the specific restriction profiles of the B. pertussis strains and allows differentiation of the strains with the ptxP structural particularities. The developed method for genotyping of strains of B. pertussis can be hhelpful when monitoring strains of the causative agent of whooping cough in system of an epidemiological surveillance over pertussis infections, allowing observation over circulating population of B.pertussis, revealing strains of the causative agent of whooping cough with high production of pertussis toxin and to watch their distribution.

  4. Strain rate effects in stress corrosion cracking

    Parkins, R.N. (Newcastle upon Tyne Univ. (UK). Dept. of Metallurgy and Engineering Materials)

    1990-03-01

    Slow strain rate testing (SSRT) was initially developed as a rapid, ad hoc laboratory method for assessing the propensity for metals an environments to promote stress corrosion cracking. It is now clear, however, that there are good theoretical reasons why strain rate, as opposed to stress per se, will often be the controlling parameter in determining whether or not cracks are nucleated and, if so, are propagated. The synergistic effects of the time dependence of corrosion-related reactions and microplastic strain provide the basis for mechanistic understanding of stress corrosion cracking in high-pressure pipelines and other structures. However, while this may be readily comprehended in the context of laboratory slow strain tests, its extension to service situations may be less apparent. Laboratory work involving realistic stressing conditions, including low-frequency cyclic loading, shows that strain or creep rates give good correlation with thresholds for cracking and with crack growth kinetics.

  5. Strain-controlled nonvolatile magnetization switching

    Geprägs, S.; Brandlmaier, A.; Brandt, M. S.; Gross, R.; Goennenwein, S. T. B.

    2014-11-01

    We investigate different approaches towards a nonvolatile switching of the remanent magnetization in single-crystalline ferromagnets at room temperature via elastic strain using ferromagnetic thin film/piezoelectric actuator hybrids. The piezoelectric actuator induces a voltage-controllable strain along different crystalline directions of the ferromagnetic thin film, resulting in modifications of its magnetization by converse magnetoelastic effects. We quantify the magnetization changes in the hybrids via ferromagnetic resonance spectroscopy and superconducting quantum interference device magnetometry. These measurements demonstrate a significant strain-induced change of the magnetization, limited by an inefficient strain transfer and domain formation in the particular system studied. To overcome these obstacles, we address practicable engineering concepts and use a model to demonstrate that a strain-controlled, nonvolatile magnetization switching should be possible in appropriately engineered ferromagnetic/piezoelectric actuator hybrids.

  6. A 3D finite-strain-based constitutive model for shape memory alloys accounting for thermomechanical coupling and martensite reorientation

    Wang, Jun; Moumni, Ziad; Zhang, Weihong; Xu, Yingjie; Zaki, Wael

    2017-06-01

    The paper presents a finite-strain constitutive model for shape memory alloys (SMAs) that accounts for thermomechanical coupling and martensite reorientation. The finite-strain formulation is based on a two-tier, multiplicative decomposition of the deformation gradient into thermal, elastic, and inelastic parts, where the inelastic deformation is further split into phase transformation and martensite reorientation components. A time-discrete formulation of the constitutive equations is proposed and a numerical integration algorithm is presented featuring proper symmetrization of the tensor variables and explicit formulation of the material and spatial tangent operators involved. The algorithm is used for finite element analysis of SMA components subjected to various loading conditions, including uniaxial, non-proportional, isothermal and adiabatic loading cases. The analysis is carried out using the FEA software Abaqus by means of a user-defined material subroutine, which is then utilized to simulate a SMA archwire undergoing large strains and rotations.

  7. Measurement of stress strain and vibrational properties of tendons

    Revel, Gian Marco; Scalise, Alessandro; Scalise, Lorenzo

    2003-08-01

    The authors present a new non-intrusive experimental procedure based on laser techniques for the measurement of mechanical properties of tendons. The procedure is based on the measurement of the first resonance frequency of the tendon by laser Doppler vibrometry during in vitro tensile experiments, with the final aim of establishing a measurement procedure to perform the mechanical characterization of tendons by extracting parameters such as the resonance frequency, also achievable during in vivo investigation. The experimental procedure is reported, taking into account the need to simulate the physiological conditions of the Achilles tendon, and the measurement technique used for the non-invasive determination of tendon cross-sectional area during tensile vibration tests at different load levels is described. The test procedure is based on a tensile machine, which measures longitudinal tendons undergoing controlled load conditions. Cross-sectional area is measured using a new non-contact procedure for the measurement of tendon perimeter (repeatability of 99% and accuracy of 2%). For each loading condition, vibration resonance frequency and damping, cross-sectional area and tensile force are measured, allowing thus a mechanical characterization of the tendon. Tendon stress-strain curves are reported. Stress-strain curves have been correlated to the first vibration resonance frequency and damping of the tendon measured using a single-point laser Doppler vibrometer. Moreover, experimental results have been compared with a theoretical model of a vibrating cord showing discrepancies. In vitro tests are reported, demonstrating the validity of the method for the comparison of different aged rabbit tendons.

  8. Genome assortment, not serogroup, defines Vibrio cholerae pandemic strains

    Brettin, Thomas S [Los Alamos National Laboratory; Bruce, David C [Los Alamos National Laboratory; Challacombe, Jean F [Los Alamos National Laboratory; Detter, John C [Los Alamos National Laboratory; Han, Cliff S [Los Alamos National Laboratory; Munik, A C [Los Alamos National Laboratory; Chertkov, Olga [Los Alamos National Laboratory; Meincke, Linda [Los Alamos National Laboratory; Saunders, Elizabeth [Los Alamos National Laboratory; Choi, Seon Y [SEOUL NATL. UNIV.; Haley, Bradd J [U. MARYLAND; Taviani, Elisa [U. MARYLAND; Jeon, Yoon - Seong [INTL. VACCINE INST. SEOUL; Kim, Dong Wook [INTL. VACCINE INST. SEOUL; Lee, Jae - Hak [SEOUL NATL. UNIV.; Walters, Ronald A [PNNL; Hug, Anwar [NATL. INST. CHOLERIC ENTERIC DIS.; Colwell, Rita R [U. MARYLAND

    2009-01-01

    Vibrio cholerae, the causative agent of cholera, is a bacterium autochthonous to the aquatic environment, and a serious public health threat. V. cholerae serogroup O1 is responsible for the previous two cholera pandemics, in which classical and El Tor biotypes were dominant in the 6th and the current 7th pandemics, respectively. Cholera researchers continually face newly emerging and re-emerging pathogenic clones carrying combinations of new serogroups as well as of phenotypic and genotypic properties. These genotype and phenotype changes have hampered control of the disease. Here we compare the complete genome sequences of 23 strains of V. cholerae isolated from a variety of sources and geographical locations over the past 98 years in an effort to elucidate the evolutionary mechanisms governing genetic diversity and genesis of new pathogenic clones. The genome-based phylogeny revealed 12 distinct V. cholerae phyletic lineages, of which one, designated the V. cholerae core genome (CG), comprises both O1 classical and EI Tor biotypes. All 7th pandemic clones share nearly identical gene content, i.e., the same genome backbone. The transition from 6th to 7th pandemic strains is defined here as a 'shift' between pathogenic clones belonging to the same O1 serogroup, but from significantly different phyletic lineages within the CG clade. In contrast, transition among clones during the present 7th pandemic period can be characterized as a 'drift' between clones, differentiated mainly by varying composition of laterally transferred genomic islands, resulting in emergence of variants, exemplified by V.cholerae serogroup O139 and V.cholerae O1 El Tor hybrid clones that produce cholera toxin of classical biotype. Based on the comprehensive comparative genomics presented in this study it is concluded that V. cholerae undergoes extensive genetic recombination via lateral gene transfer, and, therefore, genome assortment, not serogroup, should be used to

  9. Reactive Molecular Dynamics Simulations to Understand Mechanical Response of Thaumasite under Temperature and Strain Rate Effects.

    Hajilar, Shahin; Shafei, Behrouz; Cheng, Tao; Jaramillo-Botero, Andres

    2017-06-22

    Understanding the structural, thermal, and mechanical properties of thaumasite is of great interest to the cement industry, mainly because it is the phase responsible for the aging and deterioration of civil infrastructures made of cementitious materials attacked by external sources of sulfate. Despite the importance, effects of temperature and strain rate on the mechanical response of thaumasite had remained unexplored prior to the current study, in which the mechanical properties of thaumasite are fully characterized using the reactive molecular dynamics (RMD) method. With employing a first-principles based reactive force field, the RMD simulations enable the description of bond dissociation and formation under realistic conditions. From the stress-strain curves of thaumasite generated in the x, y, and z directions, the tensile strength, Young's modulus, and fracture strain are determined for the three orthogonal directions. During the course of each simulation, the chemical bonds undergoing tensile deformations are monitored to reveal the bonds responsible for the mechanical strength of thaumasite. The temperature increase is found to accelerate the bond breaking rate and consequently the degradation of mechanical properties of thaumasite, while the strain rate only leads to a slight enhancement of them for the ranges considered in this study.

  10. Strain modulations as a mechanism to reduce stress relaxation in laryngeal tissues.

    Eric J Hunter

    Full Text Available Vocal fold tissues in animal and human species undergo deformation processes at several types of loading rates: a slow strain involved in vocal fold posturing (on the order of 1 Hz or so, cyclic and faster posturing often found in speech tasks or vocal embellishment (1-10 Hz, and shear strain associated with vocal fold vibration during phonation (100 Hz and higher. Relevant to these deformation patterns are the viscous properties of laryngeal tissues, which exhibit non-linear stress relaxation and recovery. In the current study, a large strain time-dependent constitutive model of human vocal fold tissue is used to investigate effects of phonatory posturing cyclic strain in the range of 1 Hz to 10 Hz. Tissue data for two subjects are considered and used to contrast the potential effects of age. Results suggest that modulation frequency and extent (amplitude, as well as the amount of vocal fold overall strain, all affect the change in stress relaxation with modulation added. Generally, the vocal fold cover reduces the rate of relaxation while the opposite is true for the vocal ligament. Further, higher modulation frequencies appear to reduce the rate of relaxation, primarily affecting the ligament. The potential benefits of cyclic strain, often found in vibrato (around 5 Hz modulation and intonational inflection, are discussed in terms of vocal effort and vocal pitch maintenance. Additionally, elderly tissue appears to not exhibit these benefits to modulation. The exacerbating effect such modulations may have on certain voice disorders, such as muscle tension dysphonia, are explored.

  11. Human prostate supports more efficient replication of HIV-1 R5 than X4 strains ex vivo

    Denis Hélène

    2008-12-01

    Full Text Available Abstract Background In order to determine whether human prostate can be productively infected by HIV-1 strains with different tropism, and thus represent a potential source of HIV in semen, an organotypic culture of prostate from men undergoing prostatic adenomectomy for benign prostate hypertrophy (BPH was developed. The presence of potential HIV target cells in prostate tissues was investigated using immunohistochemistry. The infection of prostate explants following exposures with HIV-1 R5, R5X4 and X4 strains was analyzed through the measure of RT activity in culture supernatants, the quantification of HIV DNA in the explants and the detection of HIV RNA+ cells in situ. Results The overall prostate characteristics were retained for 21/2 weeks in culture. Numerous potential HIV-1 target cells were detected in the prostate stroma. Whilst HIV-1 R5SF162 strain consistently productively infected prostatic T lymphocytes and macrophages, the prototypic X4IIIB strain and a primary R5X4 strain showed less efficient replication in this organ. Conclusion The BPH prostate is a site of HIV-1 R5 replication that could contribute virus to semen. A limited spreading of HIV-1 X4 and R5X4 in this organ could participate to the preferential sexual transmission of HIV-1 R5 strains.

  12. Amerindian Helicobacter pylori strains go extinct, as european strains expand their host range.

    Maria G Domínguez-Bello

    Full Text Available We studied the diversity of bacteria and host in the H. pylori-human model. The human indigenous bacterium H. pylori diverged along with humans, into African, European, Asian and Amerindian groups. Of these, Amerindians have the least genetic diversity. Since niche diversity widens the sets of resources for colonizing species, we predicted that the Amerindian H. pylori strains would be the least diverse. We analyzed the multilocus sequence (7 housekeeping genes of 131 strains: 19 cultured from Africans, 36 from Spanish, 11 from Koreans, 43 from Amerindians and 22 from South American Mestizos. We found that all strains that had been cultured from Africans were African strains (hpAfrica1, all from Spanish were European (hpEurope and all from Koreans were hspEAsia but that Amerindians and Mestizos carried mixed strains: hspAmerind and hpEurope strains had been cultured from Amerindians and hpEurope and hpAfrica1 were cultured from Mestizos. The least genetically diverse H. pylori strains were hspAmerind. Strains hpEurope were the most diverse and showed remarkable multilocus sequence mosaicism (indicating recombination. The lower genetic structure in hpEurope strains is consistent with colonization of a diversity of hosts. If diversity is important for the success of H. pylori, then the low diversity of Amerindian strains might be linked to their apparent tendency to disappear. This suggests that Amerindian strains may lack the needed diversity to survive the diversity brought by non-Amerindian hosts.

  13. Strain hardening rate sensitivity and strain rate sensitivity in TWIP steels

    Bintu, Alexandra [TEMA, Department of Mechanical Engineering, University of Aveiro, Campus Universitário de Santiago, 3810-193 (Portugal); Vincze, Gabriela, E-mail: gvincze@ua.pt [TEMA, Department of Mechanical Engineering, University of Aveiro, Campus Universitário de Santiago, 3810-193 (Portugal); Picu, Catalin R. [Department of Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180 (United States); Lopes, Augusto B. [CICECO, Department of Materials and Ceramic Engineering, University of Aveiro, Campus Universitário de Santiago, 3810-193 (Portugal); Grácio, Jose J. [TEMA, Department of Mechanical Engineering, University of Aveiro, Campus Universitário de Santiago, 3810-193 (Portugal); Barlat, Frederic [Materials Mechanics Laboratory, Graduate Institute of Ferrous Technology, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of)

    2015-04-01

    TWIP steels are materials with very high strength and exceptional strain hardening capability, parameters leading to large energy absorption before failure. However, TWIP steels also exhibit reduced (often negative) strain rate sensitivity (SRS) which limits the post-necking deformation. In this study we demonstrate for an austenitic TWIP steel with 18% Mn a strong dependence of the twinning rate on the strain rate, which results in negative strain hardening rate sensitivity (SHRS). The instantaneous component of SHRS is large and negative, while its transient is close to zero. The SRS is observed to decrease with strain, becoming negative for larger strains. Direct observations of the strain rate dependence of the twinning rate are made using electron microscopy and electron backscatter diffraction, which substantiate the proposed mechanism for the observed negative SHRS.

  14. Strain hardening rate sensitivity and strain rate sensitivity in TWIP steels

    Bintu, Alexandra; Vincze, Gabriela; Picu, Catalin R.; Lopes, Augusto B.; Grácio, Jose J.; Barlat, Frederic

    2015-01-01

    TWIP steels are materials with very high strength and exceptional strain hardening capability, parameters leading to large energy absorption before failure. However, TWIP steels also exhibit reduced (often negative) strain rate sensitivity (SRS) which limits the post-necking deformation. In this study we demonstrate for an austenitic TWIP steel with 18% Mn a strong dependence of the twinning rate on the strain rate, which results in negative strain hardening rate sensitivity (SHRS). The instantaneous component of SHRS is large and negative, while its transient is close to zero. The SRS is observed to decrease with strain, becoming negative for larger strains. Direct observations of the strain rate dependence of the twinning rate are made using electron microscopy and electron backscatter diffraction, which substantiate the proposed mechanism for the observed negative SHRS

  15. Measurement of Strain and Strain Rate during the Impact of Tennis Ball Cores

    Ben Lane

    2018-03-01

    Full Text Available The aim of this investigation was to establish the strains and strain rates experienced by tennis ball cores during impact to inform material characterisation testing and finite element modelling. Three-dimensional surface strains and strain rates were measured using two high-speed video cameras and corresponding digital image correlation software (GOM Correlate Professional. The results suggest that material characterisation testing to a maximum strain of 0.4 and a maximum rate of 500 s−1 in tension and to a maximum strain of −0.4 and a maximum rate of −800 s−1 in compression would encapsulate the demands placed on the material during impact and, in turn, define the range of properties required to encapsulate the behavior of the material during impact, enabling testing to be application-specific and strain-rate-dependent properties to be established and incorporated in finite element models.

  16. Factors affecting finite strain estimation in low-grade, low-strain clastic rocks

    Pastor-Galán, Daniel; Gutiérrez-Alonso, Gabriel; Meere, Patrick A.; Mulchrone, Kieran F.

    2009-12-01

    The computer strain analysis methods SAPE, MRL and DTNNM have permitted the characterization of finite strain in two different regions with contrasting geodynamic scenarios; (1) the Talas Ala Tau (Tien Shan, Kyrgyzs Republic) and (2) the Somiedo Nappe and Narcea Antiform (Cantabrian to West Asturian-Leonese Zone boundary, Variscan Belt, NW of Iberia). The performed analyses have revealed low-strain values and the regional strain trend in both studied areas. This study also investigates the relationship between lithology (grain size and percentage of matrix) and strain estimates the two methodologies used. The results show that these methods are comparable and the absence of significant finite strain lithological control in rocks deformed under low metamorphic and low-strain conditions.

  17. The efficacy of a smoking cessation programme in patients undergoing elective surgery - a randomised clinical trial

    Azodi, O. Sadr; Lindstrom, D.; Adami, J.

    2009-01-01

    It is known that smokers constitute an important risk group of patients undergoing surgery. It is unknown how smoking cessation intervention initiated 4 weeks prior to elective surgery affects the probability of permanent cessation. We randomly assigned 117 patients, scheduled to undergo elective...

  18. Gonad Shielding for Patients Undergoing Conventional Radiological Examinations: Is There Cause for Concern?

    Karami; Zabihzadeh; Gholami

    2016-01-01

    Background Gonad shielding is one of the fundamental methods by which to protect reproductive organs in patients undergoing conventional radiological examinations. A lack of or inadequate shielding of the gonads may increase the exposure of these organs and result in malignancies future generations. Objectives The aim of this study is to investigate the prevalence of gonad shielding in patients undergoing conventional radiological...

  19. The transversus abdominis plane block provides effective postoperative analgesia in patients undergoing total abdominal hysterectomy.

    Carney, John

    2008-12-01

    Patients undergoing total abdominal hysterectomy suffer significant postoperative pain. The transversus abdominis plane (TAP) block is a recently described approach to providing analgesia to the anterior abdominal wall. We evaluated the analgesic efficacy of the TAP block in patients undergoing total abdominal hysterectomy via a transverse lower abdominal wall incision, in a randomized, controlled, double-blind clinical trial.

  20. Integrated approach to planning the remediation of sites undergoing decommissioning

    2009-01-01

    Responding to the needs of Member States, the IAEA has launched an environmental remediation guidance initiative dealing with the issues of radioactive contamination world wide. Its aim is to collate and disseminate information concerning the key issues affecting environmental remediation of contaminated sites. This IAEA initiative includes the development of documents that report on remediation technologies available, best practices, and information and guidance concerning (a) Strategy development for environmental remediation; (b) Characterization and remediation of contaminated sites and contaminated groundwater; (c) Management of waste and residues from mining and milling of uranium and thorium; (d) Decommissioning of buildings; (e) A database for contaminated sites. The subject of this present report concerns the integration of decommissioning and remediation activities at sites undergoing decommissioning and this fits within the first category of guidance documentation (strategy development). This document addresses key strategic planning issues. It is intended to provide practical advice and complement other reports that focus on decommissioning and remediation at nuclear facilities. The document is designed to encourage site remediation activities that take advantage of synergies with decommissioning in order to reduce the duplication of effort by various parties and minimize adverse impacts on human health, the environment, and costs through the transfer of experience and knowledge. To achieve this objective, the document is designed to help Member States gain perspective by summarizing available information about synergies between decommissioning and remediation, strategic planning and project management and planning tools and techniques to support decision making and remediation. Case studies are also presented as to give concrete examples of the theoretical elements elaborated in the documents. This publication investigates the potential synergies

  1. Coal in sub-Saharan-African countries undergoing desertification

    Weaver, J.N.; Brownfield, M.E.; Bergin, M.J.

    1990-01-01

    Coal has been reported in 11 of the 16 sub-Saharan countries discussed in this appraisal: Mauritania, Senegal, Mali, Niger, Benin, Nigeria, Cameroon, Central African Republic, Sudan, Ethiopia, and Somalia. No coal occurrences have been reported in Gambia, Togo, Burkina, Chad, and Djibouti but coal may be present within these countries because neighboring countries do contain coal-bearing rocks. Most of these countries are undergoing desertification or will in the near future. Wood, directly or in the form of charcoal, constitutes two-thirds of the fuel used in Africa. Destruction of forest and shrub lands for fuel is occurring at an increasing rate because of desertification and increasing energy demands. The decline in biological productivity, coupled with concentration of population in areas where water is available and crops may be grown, leads to increasing shortages of wood for fuel. Part of the present and future energy needs of the sub-Saharan region could be met by use of indigenous coal and peat. Nine sedimentary basins, completely or partially within the sub-Saharan region, have the potential of either coal and/or peat deposits of economic value: 1- Senegal Basin, 2- Taoudeni Basin and Gao Trough, 3- Niger Basin, 4- Chad Basin, 5- Chari Basin, 6- Benue Trough (Depression), 7- Sudan Trough, 8- Plateau and Rift Belt, and 9- Somali Basin. Niger and Nigeria are the only countries in sub-Saharan Africa in which coal is presently being mined as a fuel source for powerplants and domestic use. Peat occurs in the deltas, lower river, and interdunal basin areas of Senegal, Mauritania, and Sudan. Peat can be used as an alternate fuel source and is currently being tested as a soil amendment in the agricultural sector. Coal and peat exploration and development studies are urgently required and should be initiated so the coal and peat utilization potential of each country can be determined. The overall objective of these studies is to establish, within the sub

  2. Objective models of compressed breast shapes undergoing mammography

    Feng, Steve Si Jia; Patel, Bhavika; Sechopoulos, Ioannis

    2013-01-01

    Purpose: To develop models of compressed breasts undergoing mammography based on objective analysis, that are capable of accurately representing breast shapes in acquired clinical images and generating new, clinically realistic shapes. Methods: An automated edge detection algorithm was used to catalogue the breast shapes of clinically acquired cranio-caudal (CC) and medio-lateral oblique (MLO) view mammograms from a large database of digital mammography images. Principal component analysis (PCA) was performed on these shapes to reduce the information contained within the shapes to a small number of linearly independent variables. The breast shape models, one of each view, were developed from the identified principal components, and their ability to reproduce the shape of breasts from an independent set of mammograms not used in the PCA, was assessed both visually and quantitatively by calculating the average distance error (ADE). Results: The PCA breast shape models of the CC and MLO mammographic views based on six principal components, in which 99.2% and 98.0%, respectively, of the total variance of the dataset is contained, were found to be able to reproduce breast shapes with strong fidelity (CC view mean ADE = 0.90 mm, MLO view mean ADE = 1.43 mm) and to generate new clinically realistic shapes. The PCA models based on fewer principal components were also successful, but to a lesser degree, as the two-component model exhibited a mean ADE = 2.99 mm for the CC view, and a mean ADE = 4.63 mm for the MLO view. The four-component models exhibited a mean ADE = 1.47 mm for the CC view and a mean ADE = 2.14 mm for the MLO view. Paired t-tests of the ADE values of each image between models showed that these differences were statistically significant (max p-value = 0.0247). Visual examination of modeled breast shapes confirmed these results. Histograms of the PCA parameters associated with the six principal components were fitted with Gaussian distributions. The six

  3. Objective models of compressed breast shapes undergoing mammography

    Feng, Steve Si Jia [Department of Biomedical Engineering, Georgia Institute of Technology and Emory University and Department of Radiology and Imaging Sciences, Emory University, 1701 Uppergate Drive Northeast, Suite 5018, Atlanta, Georgia 30322 (United States); Patel, Bhavika [Department of Radiology and Imaging Sciences, Emory University, 1701 Uppergate Drive Northeast, Suite 5018, Atlanta, Georgia 30322 (United States); Sechopoulos, Ioannis [Departments of Radiology and Imaging Sciences, Hematology and Medical Oncology and Winship Cancer Institute, Emory University, 1701 Uppergate Drive Northeast, Suite 5018, Atlanta, Georgia 30322 (United States)

    2013-03-15

    Purpose: To develop models of compressed breasts undergoing mammography based on objective analysis, that are capable of accurately representing breast shapes in acquired clinical images and generating new, clinically realistic shapes. Methods: An automated edge detection algorithm was used to catalogue the breast shapes of clinically acquired cranio-caudal (CC) and medio-lateral oblique (MLO) view mammograms from a large database of digital mammography images. Principal component analysis (PCA) was performed on these shapes to reduce the information contained within the shapes to a small number of linearly independent variables. The breast shape models, one of each view, were developed from the identified principal components, and their ability to reproduce the shape of breasts from an independent set of mammograms not used in the PCA, was assessed both visually and quantitatively by calculating the average distance error (ADE). Results: The PCA breast shape models of the CC and MLO mammographic views based on six principal components, in which 99.2% and 98.0%, respectively, of the total variance of the dataset is contained, were found to be able to reproduce breast shapes with strong fidelity (CC view mean ADE = 0.90 mm, MLO view mean ADE = 1.43 mm) and to generate new clinically realistic shapes. The PCA models based on fewer principal components were also successful, but to a lesser degree, as the two-component model exhibited a mean ADE = 2.99 mm for the CC view, and a mean ADE = 4.63 mm for the MLO view. The four-component models exhibited a mean ADE = 1.47 mm for the CC view and a mean ADE = 2.14 mm for the MLO view. Paired t-tests of the ADE values of each image between models showed that these differences were statistically significant (max p-value = 0.0247). Visual examination of modeled breast shapes confirmed these results. Histograms of the PCA parameters associated with the six principal components were fitted with Gaussian distributions. The six

  4. Objective models of compressed breast shapes undergoing mammography

    Feng, Steve Si Jia; Patel, Bhavika; Sechopoulos, Ioannis

    2013-01-01

    Purpose: To develop models of compressed breasts undergoing mammography based on objective analysis, that are capable of accurately representing breast shapes in acquired clinical images and generating new, clinically realistic shapes. Methods: An automated edge detection algorithm was used to catalogue the breast shapes of clinically acquired cranio-caudal (CC) and medio-lateral oblique (MLO) view mammograms from a large database of digital mammography images. Principal component analysis (PCA) was performed on these shapes to reduce the information contained within the shapes to a small number of linearly independent variables. The breast shape models, one of each view, were developed from the identified principal components, and their ability to reproduce the shape of breasts from an independent set of mammograms not used in the PCA, was assessed both visually and quantitatively by calculating the average distance error (ADE). Results: The PCA breast shape models of the CC and MLO mammographic views based on six principal components, in which 99.2% and 98.0%, respectively, of the total variance of the dataset is contained, were found to be able to reproduce breast shapes with strong fidelity (CC view mean ADE = 0.90 mm, MLO view mean ADE = 1.43 mm) and to generate new clinically realistic shapes. The PCA models based on fewer principal components were also successful, but to a lesser degree, as the two-component model exhibited a mean ADE = 2.99 mm for the CC view, and a mean ADE = 4.63 mm for the MLO view. The four-component models exhibited a mean ADE = 1.47 mm for the CC view and a mean ADE = 2.14 mm for the MLO view. Paired t-tests of the ADE values of each image between models showed that these differences were statistically significant (max p-value = 0.0247). Visual examination of modeled breast shapes confirmed these results. Histograms of the PCA parameters associated with the six principal components were fitted with Gaussian distributions. The six

  5. Blood transfusion in children with sickle cell disease undergoing tonsillectomy.

    Atwood, Carlyn M; Gnagi, Sharon H; Teufel, Ronald J; Nguyen, Shaun A; White, David R

    2017-12-01

    Tonsillectomy is the second most common surgery in children with sickle cell disease. These children are at an increased risk of perioperative complications due to vaso-occlusive events. Although controversial, preoperative blood transfusions are sometimes given in an effort to prevent such complications. The purpose of this study is to analyze trends in the use of blood transfusion for management of children with sickle cell disease (SCD) undergoing tonsillectomy in a national database. Patients in the 1997-2012 KID with a primary procedure matching the ICD-9 procedure code for tonsillectomy (28.2-28.3) and diagnosis code for SCD (282.60-282.69) were examined. Patients were split into groups by blood transfusion status and compared across variables including complication rate, length of stay (LOS), and hospital charges. Statistical analysis included chi-square test for trend, Mann-Whitney U test, and independent t-test. 1133 patients with SCD underwent tonsillectomy. There was a strong positive correlation between increasing chronologic year and the proportion of patients receiving blood transfusions, 47 (30.1%) in 1997 to 78 (42.5%) in 2012 (r = 0.94, p = 0.005). During this period, there was no significant change in the rate of complications (r = -0.1, p = 0.87). Overall, patients receiving blood transfusion had a longer mean LOS (3.1 ± 2.4 days vs. 2.5 ± 2.2 days, p blood transfusion. The rate of complications in the transfusion group, 18 of 352(5.1%), was not significantly different (p = 0.48) from the group without transfusion, 40 of 626 (6.4%). From 1997 to 2012, there was a significant increase in the proportion of patients with SCD receiving perioperative blood transfusions for tonsillectomy. While the frequency of transfusion rose, those who received a transfusion had similar complication rates with increased charges and length of hospital stays compared to those who did not receive a transfusion. Copyright © 2017 Elsevier B.V. All

  6. Soil Quality in Mining Areas Undergoing Ecological Restoration

    Dinarowski, Marcela; Casagrande, José Carlos; Bizuti, Denise T. G.; Silva, Luiz Gabriel; Soares, Marcio Roberto; Brancalion, Pedro H. S.

    2014-05-01

    Mining is one of the anthropogenic activities most impactful to natural resources, and can profoundly affect the resilience of ecosystems depending on the level of soil degradation. Ecological restoration has generated promising results even in situations of degradation as intense as those of mining. The aim of this study was to evaluate the quality of the soil in areas explored by the bauxite extraction undergoing restoration: recently mined, seven years, 20 years and native forest. The studied areas are located in the municipality of Poços de Caldas-MG, belonging to ALCOA Alumínio. The mined-out areas for seven and twenty years were uncompressed and received topsoil, liming and fertilization with nitrogen, phosphorus and potassium. Samples for chemical analyses of soil fertility were carried out at depths of 0-5, 5-10, 10-20, 20-40 and 40-60 cm. Soil quality was evaluated by pondered additive model. The parameters were considered organic matter (0.6) and bases saturation (0.4) for soil fertility function (0.6) and calcium (0.5) and aluminum saturation (0.5) for the function root development (0.4) - (the numbers in parentheses represent the weights attributed). Despite the high content, only the organic matter was not a parameter enough to classify the soil quality, once the native forest has very low base saturation (7%). The soil quality index(SQI) obtained allowed to classify the areas, being the first restored 20 years ago with SQI equal to 0.7 followed of the restored 7 years ago, native forest and newly mined with SQIs equal to 0.6, 04 and 0.3, respectively. The native tropical forests have low soil fertility, keeping by the cycling of nutrients. This demonstrates the need for the degraded areas, especially the mined, are uncompressed to allow storage of water and root development, in addition to the replacement of nutrients and soil acidity correction, especially high levels of aluminum saturation (66%) and low calcium (3 mmolcdm-3).

  7. Rupture prediction for induction bends under opening mode bending with emphasis on strain localization

    Mitsuya, Masaki; Sakanoue, Takashi

    2015-01-01

    This study focuses on the opening mode of induction bends; this mode represents the deformation outside a bend. Bending experiments on induction bends are shown and the manner of failure of these bends was investigated. Ruptures occur at the intrados of the bends, which undergo tensile stress, and accompany the local reduction of wall thickness, i.e., necking that indicates strain localization. By implementing finite element analysis (FEA), it was shown that the rupture is dominated not by the fracture criterion of material but by the initiation of strain localization that is a deformation characteristic of the material. These ruptures are due to the rapid increase of local strain after the initiation of strain localization and suddenly reach the fracture criterion. For the evaluation of the deformability of the bends, a method based on FEA that can predict the displacement at the rupture is proposed. We show that the yield surface shape and the true stress–strain relationship after uniform elongation have to be defined on the basis of the actual properties of the bend material. The von Mises yield criterion, which is commonly used in cases of elastic–plastic FEA, could not predict the rupture and overestimated the deformability. In contrast, a yield surface obtained by performing tensile tests on a biaxial specimen could predict the rupture. The prediction of the rupture was accomplished by an inverse calibration method that determined the true stress-strain relationship after uniform elongation. As an alternative to the inverse calibration, a simple extrapolation method of the true stress-strain relationship after uniform elongation which can predict the rupture is proposed. - Highlights: • A method based on FEA that can predict the displacement at the rupture is proposed. • The yield surface shape and the true stress–strain have to be defined precisely. • The von Mises yield criterion overestimated the deformability. • The ruptures are due to the

  8. Chemical Profile of Monascus ruber Strains

    Ahamed M. Moharram

    2012-01-01

    Full Text Available Chemical profile of Monascus ruber strains has been studied using gas chromatography-mass spectrometry (GC/MS analysis. The colour intensity of the red pigment and secondary metabolic products of two M. ruber strains (AUMC 4066 and AUMC 5705 cultivated on ten different media were also studied. Metabolic products can be classified into four categories: anticholesterol, anticancer, food colouring, and essential fatty acids necessary for human health. Using GC/MS, the following 88 metabolic products were detected: butyric acid and its derivatives (25 products, other fatty acids and their derivatives (19 products, pyran and its derivatives (22 products and other metabolites (22 products. Among these, 32 metabolites were specific for AUMC 4066 strain and 34 for AUMC 5705 strain, whereas 22 metabolites were produced by both strains on different tested substrates. Production of some metabolites depended on the substrate used. High number of metabolites was recorded in the red pigment extract obtained by both strains grown on malt broth and malt agar. Also, 42 aroma compounds were recorded (4 alcohols, 2 benzaldehydes, 27 esters, 3 lactones, 1 phenol, 1 terpenoid, 3 thiol compounds and acetate-3-mercapto butyric acid. Thin layer chromatography and GC/MS analyses revealed no mycotoxin citrinin in any media used for the growth of the two M. ruber strains.

  9. Resolution of axial shear strain elastography

    Thitaikumar, Arun; Righetti, Raffaella; Krouskop, Thomas A; Ophir, Jonathan

    2006-01-01

    The technique of mapping the local axial component of the shear strain due to quasi-static axial compression is defined as axial shear strain elastography. In this paper, the spatial resolution of axial shear strain elastography is investigated through simulations, using an elastically stiff cylindrical lesion embedded in a homogeneously softer background. Resolution was defined as the smallest size of the inclusion for which the strain value at the inclusion/background interface was greater than the average of the axial shear strain values at the interface and inside the inclusion. The resolution was measured from the axial shear strain profile oriented at 45 0 to the axis of beam propagation, due to the absence of axial shear strain along the normal directions. The effects of the ultrasound system parameters such as bandwidth, beamwidth and transducer element pitch along with signal processing parameters such as correlation window length (W) and axial shift (ΔW) on the estimated resolution were investigated. The results show that the resolution (at 45 0 orientation) is determined by the bandwidth and the beamwidth. However, the upper bound on the resolution is limited by the larger of the beamwidth and the window length, which is scaled inversely to the bandwidth. The results also show that the resolution is proportional to the pitch and not significantly affected by the axial window shift

  10. Development of intra-strain self-cloning procedure for breeding baker's yeast strains.

    Nakagawa, Youji; Ogihara, Hiroyuki; Mochizuki, Chisato; Yamamura, Hideki; Iimura, Yuzuru; Hayakawa, Masayuki

    2017-03-01

    Previously reported self-cloning procedures for breeding of industrial yeast strains require DNA from other strains, plasmid DNA, or mutagenesis. Therefore, we aimed to construct a self-cloning baker's yeast strain that exhibits freeze tolerance via an improved self-cloning procedure. We first disrupted the URA3 gene of a prototrophic baker's yeast strain without the use of any marker gene, resulting in a Δura3 homozygous disruptant. Then, the URA3 gene of the parental baker's yeast strain was used as a selection marker to introduce the constitutive TDH3 promoter upstream of the PDE2 gene encoding high-affinity cyclic AMP phosphodiesterase. This self-cloning procedure was performed without using DNA from other Saccharomyces cerevisiae strains, plasmid DNA, or mutagenesis and was therefore designated an intra-strain self-cloning procedure. Using this self-cloning procedure, we succeeded in producing self-cloning baker's yeast strains that harbor the TDH3p-PDE2 gene heterozygously and homozygously, designated TDH3p-PDE2 hetero and TDH3p-PDE2 homo strains, respectively. These self-cloning strains expressed much higher levels of PDE2 mRNA than the parental strain and exhibited higher viability after freeze stress, as well as higher fermentation ability in frozen dough, when compared with the parental strain. The TDH3p-PDE2 homo strain was genetically more stable than the TDH3p-PDE2 hetero strain. These results indicate that both heterozygous and homozygous strains of self-cloning PDE2-overexpressing freeze-tolerant strains of industrial baker's yeast can be prepared using the intra-strain self-cloning procedure, and, from a practical viewpoint, the TDH3p-PDE2 homo strain constructed in this study is preferable to the TDH3p-PDE2 hetero strain for frozen dough baking. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  11. [Screening and optimization of cholesterol conversion strain].

    Fan, Dan; Xiong, Bingjian; Pang, Cuiping; Zhu, Xiangdong

    2014-10-04

    Bacterial strain SE-1 capable of transforming cholesterol was isolated from soil and characterized. The transformation products were identified. Fermentation conditions were optimized for conversion. Cholesterol was used as sole carbon source to isolate strain SE-1. Morphology, physiological and biochemical characteristics of strain SE-1 were studied. 16S rRNA gene was sequenced and subjected to phylogenetic analysis. Fermentation supernatants were extracted with chloroform, the transformation products were analyzed by silica gel thin layer chromatography and Sephadex LH20. Their structures were identified by 1H-NMR and 13C-NMR. Fermentation medium including carbon and nitrogen, methods of adding substrates and fermentation conditions for Strain SE-1 were optimized. Strain SE-1 was a Gram-negative bacterium, exhibiting the highest homologs to Burkholderia cepacia based on the physiological analysis. The sequence analysis of 16S rRNA gene of SE-1 strain and comparison with related Burkholderia show that SE-1 strain was very close to B. cepacia (Genbank No. U96927). The similarity was 99%. The result of silica gel thin layer chromatography shows that strain SE-1 transformed cholesterol to two products, 7beta-hydroxycholesterol and the minor product was 7-oxocholesterol. The optimum culture conditions were: molasses 5%, (NH4 )2SO4 0.3%, 4% of inoculation, pH 7.5 and 36 degrees C. Under the optimum culture condition, the conversion rate reached 34.4% when concentration of cholesterol-Tween 80 was 1 g/L. Cholesterol 7beta-hydroxylation conversion rate under optimal conditions was improved by 20.8%. Strain SE-1 isolated from soil is capable of converting cholesterol at lab-scale.

  12. Fluorogenic Strain-Promoted Alkyne-Diazo Cycloadditions.

    Friscourt, Frédéric; Fahrni, Christoph J; Boons, Geert-Jan

    2015-09-28

    Fluorogenic reactions, in which non- or weakly fluorescent reagents produce highly fluorescent products, are attractive for detecting a broad range of compounds in the fields of bioconjugation and material sciences. Herein, we report that a dibenzocyclooctyne derivative modified with a cyclopropenone moiety (Fl-DIBO) can undergo fast strain-promoted cycloaddition reactions under catalyst-free conditions with azides, nitrones, nitrile oxides, as well as mono- and disubstituted diazo-derivatives. Although the reaction with nitrile oxides, nitrones, and disubstituted diazo compounds gave cycloadducts with low quantum yield, monosubstituted diazo reagents produced 1H-pyrazole derivatives that exhibited an approximately 160-fold fluorescence enhancement over Fl-DIBO combined with a greater than 10,000-fold increase in brightness. Concluding from quantum chemical calculations, fluorescence quenching of 3H-pyrazoles, which are formed by reaction with disubstituted diazo-derivatives, is likely due to the presence of energetically low-lying (n,π*) states. The fluorogenic probe Fl-DIBO was successfully employed for the labeling of diazo-tagged proteins without detectable background signal. Diazo-derivatives are emerging as attractive reporters for the labeling of biomolecules, and the studies presented herein demonstrate that Fl-DIBO can be employed for visualizing such biomolecules without the need for probe washout. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Factors That Influence the Decision to Undergo Labiaplasty: Media, Relationships, and Psychological Well-Being.

    Sharp, Gemma; Tiggemann, Marika; Mattiske, Julie

    2016-04-01

    An increasing number of women are undergoing labiaplasty procedures; however, very little is known about the psychological factors that motivate women to seek out this procedure. To investigate the factors that influence women's decisions to undergo labiaplasty. Women seeking to undergo labiaplasty (n = 35) were compared with women who were not (n = 30). Standardized measures were employed to assess the patients' media exposure (television, the Internet, advertising, pornography), relationship quality, and psychological well-being. Women's motivations for deciding to undergo a labiaplasty procedure were characterized as "appearance," "functional," "sexual," or "psychological" motivations, with concerns about the labia's appearance being the most commonly reported motivation. Correspondingly, women seeking labiaplasty were significantly less satisfied with the appearance of their genitals than the comparison group (P media exposure and relationship status as important factors that influence women's decisions to undergo labiaplasty. 3 Risk. © 2016 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

  14. Ductile Damage Evolution and Strain Path Dependency

    Tasan, C. C.; Hoefnagels, J. M. P.; Peerlings, R. H. J.; Geers, M. G. D.; ten Horn, C. H. L. J.; Vegter, H.

    2007-01-01

    Forming limit diagrams are commonly used in sheet metal industry to define the safe forming regions. These diagrams are built to define the necking strains of sheet metals. However, with the rise in the popularity of advance high strength steels, ductile fracture through damage evolution has also emerged as an important parameter in the determination of limit strains. In this work, damage evolution in two different steels used in the automotive industry is examined to observe the relationship between damage evolution and the strain path that is followed during the forming operation

  15. Strain-energy effects on dynamic fragmentation

    Glenn, L.A.; Chudnovsky, A.

    1986-01-01

    Grady's model of the dynamic fragmentation process, in which the average fragment size is determined by balancing the local kinetic energy and the surface energy, is modified to include the stored elastic (strain) energy. The revised model predicts that the strain energy should dominate for brittle materials, with low fracture toughness and high fracture-initiation stress. This conclusion is not borne out, however, by limited experimental data on brittle steels, even when the kinetic-energy density is small compared with the strain-energy density

  16. Stability of germanene under tensile strain

    Kaloni, Thaneshwor P.

    2013-09-01

    The stability of germanene under biaxial tensile strain and the accompanying modifications of the electronic properties are studied by density functional theory. The phonon spectrum shows that up to 16% strain the germanene lattice is stable, where the Dirac cone shifts towards higher energy and hole-doped Dirac states are achieved. The latter is due to weakening of the Ge-Ge bonds and reduction of the s-p hybridization. Our calculated Grüneisen parameter shows a similar dependence on the strain as reported for silicene (which is different from that of graphene). © 2013 Elsevier B.V. All rights reserved.

  17. Stability of germanene under tensile strain

    Kaloni, Thaneshwor P.; Schwingenschlö gl, Udo

    2013-01-01

    The stability of germanene under biaxial tensile strain and the accompanying modifications of the electronic properties are studied by density functional theory. The phonon spectrum shows that up to 16% strain the germanene lattice is stable, where the Dirac cone shifts towards higher energy and hole-doped Dirac states are achieved. The latter is due to weakening of the Ge-Ge bonds and reduction of the s-p hybridization. Our calculated Grüneisen parameter shows a similar dependence on the strain as reported for silicene (which is different from that of graphene). © 2013 Elsevier B.V. All rights reserved.

  18. Rat Strain Ontology: structured controlled vocabulary designed to facilitate access to strain data at RGD.

    Nigam, Rajni; Munzenmaier, Diane H; Worthey, Elizabeth A; Dwinell, Melinda R; Shimoyama, Mary; Jacob, Howard J

    2013-11-22

    The Rat Genome Database (RGD) ( http://rgd.mcw.edu/) is the premier site for comprehensive data on the different strains of the laboratory rat (Rattus norvegicus). The strain data are collected from various publications, direct submissions from individual researchers, and rat providers worldwide. Rat strain, substrain designation and nomenclature follow the Guidelines for Nomenclature of Mouse and Rat Strains, instituted by the International Committee on Standardized Genetic Nomenclature for Mice. While symbols and names aid in identifying strains correctly, the flat nature of this information prohibits easy search and retrieval, as well as other data mining functions. In order to improve these functionalities, particularly in ontology-based tools, the Rat Strain Ontology (RS) was developed. The Rat Strain Ontology (RS) reflects the breeding history, parental background, and genetic manipulation of rat strains. This controlled vocabulary organizes strains by type: inbred, outbred, chromosome altered, congenic, mutant and so on. In addition, under the chromosome altered category, strains are organized by chromosome, and further by type of manipulations, such as mutant or congenic. This allows users to easily retrieve strains of interest with modifications in specific genomic regions. The ontology was developed using the Open Biological and Biomedical Ontology (OBO) file format, and is organized on the Directed Acyclic Graph (DAG) structure. Rat Strain Ontology IDs are included as part of the strain report (RS: ######). As rat researchers are often unaware of the number of substrains or altered strains within a breeding line, this vocabulary now provides an easy way to retrieve all substrains and accompanying information. Its usefulness is particularly evident in tools such as the PhenoMiner at RGD, where users can now easily retrieve phenotype measurement data for related strains, strains with similar backgrounds or those with similar introgressed regions. This

  19. Biological assay of attenuated strain NADL-2 and virulent strain NADL-8 of porcine parvovirus.

    Mengeling, W L; Pejsak, Z; Paul, P S

    1984-11-01

    Attenuated strain NADL-2 and virulent strain NADL-8 of porcine parvovirus (PPV) were titrated in vivo and in vitro under similar conditions to provide a better understanding of some of the factors involved in virulence of PPV in causing maternal reproductive failure of swine. Both strains cause fetal death when they are injected directly into fetal fluids, but only strain NADL-8 does so when administered to pregnant swine. The strains were tested for their hemagglutinating activity (HA), median cell culture infective dose (CCID50), median fetal infective dose (FID50), and median fetal lethal dose (FLD50). The FID50 and FLD50 were determined by injecting virus directly into the amniotic fluid of fetuses in utero at 44 +/- 2 days of gestation and collecting the fetuses 15 +/- 1 days later. Both strains had an HA titer of 64, suggesting that there is a similar number of virions in stock preparations. However, other measurements differed markedly. The CCID50, FID50, and FLD50 were 10(5.5), 10(3.5), and 10(0.5), respectively, for strain NADL-2, and 10(4.5), 10(7.7), and 10(6.3), respectively, for strain NADL-8. Collectively, the values indicate that more than 10,000 times as much strain NADL-2 would need to reach the conceptus transplacentally to establish infection. These observations may help to explain the different consequences of oronasal exposure of pregnant swine to these strains of PPV.

  20. Solitary waves in morphogenesis: Determination fronts as strain-cued strain transformations among automatous cells

    Cox, Brian N.; Landis, Chad M.

    2018-02-01

    We present a simple theory of a strain pulse propagating as a solitary wave through a continuous two-dimensional population of cells. A critical strain is assumed to trigger a strain transformation, while, simultaneously, cells move as automata to tend to restore a preferred cell density. We consider systems in which the strain transformation is a shape change, a burst of proliferation, or the commencement of growth (which changes the shape of the population sheet), and demonstrate isomorphism among these cases. Numerical and analytical solutions describe a strain pulse whose height does not depend on how the strain disturbance was first launched, or the rate at which the strain transformation is achieved, or the rate constant in the rule for the restorative cell motion. The strain pulse is therefore very stable, surviving the imposition of strong perturbations: it would serve well as a timing signal in development. The automatous wave formulation is simple, with few model parameters. A strong case exists for the presence of a strain pulse during amelogenesis. Quantitative analysis reveals a simple relationship between the velocity of the leading edge of the pulse in amelogenesis and the known speed of migration of ameloblast cells. This result and energy arguments support the depiction of wave motion as an automatous cell response to strain, rather than as a response to an elastic energy gradient. The theory may also contribute to understanding the determination front in somitogenesis, moving fronts of convergent-extension transformation, and mitotic wavefronts in the syncytial drosophila embryo.

  1. Ureaplasma parvum undergoes selection in utero resulting in genetically diverse isolates colonizing the chorioamnion of fetal sheep.

    Dando, Samantha J; Nitsos, Ilias; Polglase, Graeme R; Newnham, John P; Jobe, Alan H; Knox, Christine L

    2014-02-01

    Ureaplasmas are the microorganisms most frequently isolated from the amniotic fluid of pregnant women and can cause chronic intrauterine infections. These tiny bacteria are thought to undergo rapid evolution and exhibit a hypermutatable phenotype; however, little is known about how ureaplasmas respond to selective pressures in utero. Using an ovine model of chronic intraamniotic infection, we investigated if exposure of ureaplasmas to subinhibitory concentrations of erythromycin could induce phenotypic or genetic indicators of macrolide resistance. At 55 days gestation, 12 pregnant ewes received an intraamniotic injection of a nonclonal, clinical Ureaplasma parvum strain followed by (i) erythromycin treatment (intramuscularly, 30 mg/kg/day, n = 6) or (ii) saline (intramuscularly, n = 6) at 100 days gestation. Fetuses were then delivered surgically at 125 days gestation. Despite injecting the same inoculum into all the ewes, significant differences between amniotic fluid and chorioamnion ureaplasmas were detected following chronic intraamniotic infection. Numerous polymorphisms were observed in domain V of the 23S rRNA gene of ureaplasmas isolated from the chorioamnion (but not the amniotic fluid), resulting in a mosaiclike sequence. Chorioamnion isolates also harbored the macrolide resistance genes erm(B) and msr(D) and were associated with variable roxithromycin minimum inhibitory concentrations. Remarkably, this variability occurred independently of exposure of ureaplasmas to erythromycin, suggesting that low-level erythromycin exposure does not induce ureaplasmal macrolide resistance in utero. Rather, the significant differences observed between amniotic fluid and chorioamnion ureaplasmas suggest that different anatomical sites may select for ureaplasma subtypes within nonclonal, clinical strains. This may have implications for the treatment of intrauterine ureaplasma infections.

  2. Five challenges in modelling interacting strain dynamics

    Paul S. Wikramaratna

    2015-03-01

    Full Text Available Population epidemiological models where hosts can be infected sequentially by different strains have the potential to help us understand many important diseases. Researchers have in recent years started to develop and use such models, but the extra layer of complexity from multiple strains brings with it many technical challenges. It is therefore hard to build models which have realistic assumptions yet are tractable. Here we outline some of the main challenges in this area. First we begin with the fundamental question of how to translate from complex small-scale dynamics within a host to useful population models. Next we consider the nature of so-called “strain space”. We describe two key types of host heterogeneities, and explain how models could help generate a better understanding of their effects. Finally, for diseases with many strains, we consider the challenge of modelling how immunity accumulates over multiple exposures.

  3. (HN1) strain of Aspergillus niger

    login123

    2016-09-26

    Sep 26, 2016 ... olive oil) increased the production of lipase up to 20% in case of both the strains. The production of ... insoluble triacylglycerols to generate free fatty acids, mono and ... Two fermentation processes, including solid state.

  4. Mumps vaccine virus strains and aseptic meningitis.

    Bonnet, Marie-Claude; Dutta, Anil; Weinberger, Clement; Plotkin, Stanley A

    2006-11-30

    Mumps immunization can easily be included in national schedules, particularly if combined with measles or measles and rubella vaccines, but debate continues concerning the relative safety of various licensed mumps vaccine strains. The opportunities for control of mumps are also being affected by differences in the cost of the vaccines prepared with different strains of mumps virus. The present report evaluates available data on the association of the Urabe and other strains of mumps vaccine with the occurrence of aseptic meningitis. We also review the comparative immunogenicity and efficacies of the most widely used mumps vaccines in controlled clinical trials and field evaluations, and briefly examine relative cost as it relates to the implementation of national immunization programs. We conclude that extensive experience with the most widely used mumps vaccine strains in many countries has shown that the risk-benefit ratio of live mumps vaccines is highly favourable for vaccination, despite the occasional occurence of aseptic meningitis.

  5. Characterization of 3 Strains of Yersinia Pestis

    Kournikakis, B

    2000-01-01

    .... Antibiotic sensitivities showed that the 3 strains were sensitive to aminoglycosides, the cephalosporins/ cephams, most of the beta lactams/penicillins (e.g. ampicillin) and quinolones (e.g. ciprofloxacin...

  6. Flexoelectricity: strain gradient effects in ferroelectrics

    Ma Wenhui [Department of Physics, Shantou Unversity, Shantou, Guangdong 515063 (China)

    2007-12-15

    Mechanical strain gradient induced polarization effect or flexoelectricity in perovskite-type ferroelectric and relaxor ferroelectric ceramics was investigated. The flexoelectric coefficients measured at room temperature ranged from about 1 {mu} C m{sup -1} for lead zirconate titanate to 100 {mu} C m{sup -1} for barium strontium titanate. Flexoelectric effects were discovered to be sensitive to chemical makeup, phase symmetry, and domain structures. Based on phenomenological discussion and experimental data on flexoelectricity, the present study proposed that mechanical strain gradient field could influence polarization responses in a way analogous to electric field. Flexoelectric coefficients were found to be nonlinearly enhanced by dielectric permittivity and strain gradient. Interfacial mismatch in epitaxial thin films can give rise to high strain gradients, enabling flexoelectric effects to make a significant impact in properly engineered ferroelectric heterostructure systems.

  7. Review of strain buckling: analysis methods

    Moulin, D.

    1987-01-01

    This report represents an attempt to review the mechanical analysis methods reported in the literature to account for the specific behaviour that we call buckling under strain. In this report, this expression covers all buckling mechanisms in which the strains imposed play a role, whether they act alone (as in simple buckling under controlled strain), or whether they act with other loadings (primary loading, such as pressure, for example). Attention is focused on the practical problems relevant to LMFBR reactors. The components concerned are distinguished by their high slenderness ratios and by rather high thermal levels, both constant and variable with time. Conventional static buckling analysis methods are not always appropriate for the consideration of buckling under strain. New methods must therefore be developed in certain cases. It is also hoped that this review will facilitate the coding of these analytical methods to aid the constructor in his design task and to identify the areas which merit further investigation

  8. Systems strategies for developing industrial microbial strains

    Lee, Sang Yup; Kim, Hyun Uk

    2015-01-01

    Industrial strain development requires system-wide engineering and optimization of cellular metabolism while considering industrially relevant fermentation and recovery processes. It can be conceptualized as several strategies, which may be implemented in an iterative fashion and in different...

  9. Characterization of 21 Strains of Bacillus Anthracis

    Kournikakis, B

    2000-01-01

    Twenty-one strains of Bacillus anthracis currently held in the culture collection at DRES were characterized by colonial morphology, antibiotic sensitivity and BiologTM metabolic identification profiles...

  10. Phenotypic variability among strains of Pasteurella multocida ...

    STORAGESEVER

    2008-05-02

    May 2, 2008 ... Available online at http://www.academicjournals.org/AJB. ISSN 1684–5315 ... extended phenotypic characterization methods supported by DNA ... septicaemia African (Obudu) strain (E:2) which are currently employed as ...

  11. Job strain and the risk of stroke

    Fransson, Eleonor I; Nyberg, Solja T; Heikkilä, Katriina

    2015-01-01

    BACKGROUND AND PURPOSE: Psychosocial stress at work has been proposed to be a risk factor for cardiovascular disease. However, its role as a risk factor for stroke is uncertain. METHODS: We conducted an individual-participant-data meta-analysis of 196 380 males and females from 14 European cohort...... studies to investigate the association between job strain, a measure of work-related stress, and incident stroke. RESULTS: In 1.8 million person-years at risk (mean follow-up 9.2 years), 2023 first-time stroke events were recorded. The age- and sex-adjusted hazard ratio for job strain relative to no job....... CONCLUSION: Job strain may be associated with an increased risk of ischemic stroke, but further research is needed to determine whether interventions targeting job strain would reduce stroke risk beyond existing preventive strategies....

  12. The radiographic observation of the cervical strain

    Rhee, Chung Sik

    1972-01-01

    A total of 100 cases of cervical disorders were analysed of clinical signs and symptoms. The cervical strain is proved by the loss of normal lordotic curvature of the cervical spinal column on the lateral x-ray film in Ewha University Hospital from January, 1970 to december 1971 with the following results. 1. The 53 cervical strain was diagnosed in radiographic study for its abnormal locations. The hyperextension with abnormal curve is twice more after than hyperflection type. 2. The most frequent location of the cervical strain is demonstrated in the 4-6 th cervical spinal bodies (80%). 3. Most pronounced symptoms of cervical strain are local tenderness (40%), limitation of motion (17%) and radiating pain (15%). 4. The ratio of the sex incidence of male female was 3:2

  13. The radiographic observation of the cervical strain

    Rhee, Chung Sik [Ewha Womans University College of Medicine, Seoul (Korea, Republic of)

    1972-12-15

    A total of 100 cases of cervical disorders were analysed of clinical signs and symptoms. The cervical strain is proved by the loss of normal lordotic curvature of the cervical spinal column on the lateral x-ray film in Ewha University Hospital from January, 1970 to december 1971 with the following results. 1. The 53 cervical strain was diagnosed in radiographic study for its abnormal locations. The hyperextension with abnormal curve is twice more after than hyperflection type. 2. The most frequent location of the cervical strain is demonstrated in the 4-6 th cervical spinal bodies (80%). 3. Most pronounced symptoms of cervical strain are local tenderness (40%), limitation of motion (17%) and radiating pain (15%). 4. The ratio of the sex incidence of male female was 3:2.

  14. Comparative transcriptional profiling of Bacillus cereus sensu lato strains during growth in CO2-bicarbonate and aerobic atmospheres.

    Karla D Passalacqua

    Full Text Available Bacillus species are spore-forming bacteria that are ubiquitous in the environment and display a range of virulent and avirulent phenotypes. This range is particularly evident in the Bacillus cereus sensu lato group; where closely related strains cause anthrax, food-borne illnesses, and pneumonia, but can also be non-pathogenic. Although much of this phenotypic range can be attributed to the presence or absence of a few key virulence factors, there are other virulence-associated loci that are conserved throughout the B. cereus group, and we hypothesized that these genes may be regulated differently in pathogenic and non-pathogenic strains.Here we report transcriptional profiles of three closely related but phenotypically unique members of the Bacillus cereus group--a pneumonia-causing B. cereus strain (G9241, an attenuated strain of B. anthracis (Sterne 34F(2, and an avirulent B. cereus strain (10987--during exponential growth in two distinct atmospheric environments: 14% CO(2/bicarbonate and ambient air. We show that the disease-causing Bacillus strains undergo more distinctive transcriptional changes between the two environments, and that the expression of plasmid-encoded virulence genes was increased exclusively in the CO(2 environment. We observed a core of conserved metabolic genes that were differentially expressed in all three strains in both conditions. Additionally, the expression profiles of putative virulence genes in G9241 suggest that this strain, unlike Bacillus anthracis, may regulate gene expression with both PlcR and AtxA transcriptional regulators, each acting in a different environment.We have shown that homologous and even identical genes within the genomes of three closely related members of the B. cereus sensu lato group are in some instances regulated very differently, and that these differences can have important implications for virulence. This study provides insights into the evolution of the B. cereus group, and

  15. A strain gradient plasticity theory with application to wire torsion

    Liu, J. X.; El Sayed, Tamer S.

    2014-01-01

    Based on the framework of the existing strain gradient plasticity theories, we have examined three kinds of relations for the plastic strain dependence of the material intrinsic length scale, and thus developed updated strain gradient plasticity

  16. MM98.57 Quantification of Combined Strain Paths

    Nielsen, Morten Sturgård; Wanheim, Tarras

    1998-01-01

    this curve into useful scalar relations from experimental data.The strain history for plane strain when assuming volume constancy may be plotted in a shear strain, normal strain diagram, which has the property of showing both the rotation of principal deformation axes during the deformation and the amount...... is to describe the total strain history as a curve in the 6-dimensional shear strain, normal strain space. In order to be able to use these experimental data for calculation, the development of this strain curve must be transformed into a set of scalar relations that may be used for predicting the yield surface...... at a given point in a new strain history. A simple example of this concept is to take the length of the strain curve as describing scalar relation: E.g. to use the equivalent strain as parameter for describing the yield stress. This paper focuses on the strain curve concept and the possibilities to convert...

  17. On generalization uniaxial stress-strain relation

    Sahay, C.; Dubey, R.N.

    1980-01-01

    Different forms of constitutive relations have been advanced for elastic, plastic and elastic-plastic behaviour of materials. It is shown that the various forms of the stress-strain relationship are specialized forms of generalization of a single stress-strain relation. For example, it is shown how the laws of elastic deformation, and the incremental and total deformation relationship for plastic behaviour are derivable from the Ramberg-Osgood relation. (orig.)

  18. Survival and activity of individual bioaugmentation strains

    Dueholm, Morten Simonsen; G. Marquesa, Irina; Karst, Søren Michael

    2015-01-01

    Successful application of bioaugmentation for enhanced degradation of environmental pollutants is often limited by the lack of methods to monitor the survival and activity of individual bioaugmentation strains. However, recent advancements in sequencing technologies and molecular techniques now...... allow us to address these limitations. Here a complementing set of general applicable molecular methods are presented that provides detailed information on the performance of individual bioaugmentation strains under in situ conditions. The approach involves genome sequencing to establish highly specific...

  19. Strain limit criteria to predict failure

    Flanders, H.E.

    1995-01-01

    In recent years extensive effort has been expended to qualify existing structures for conditions that are beyond the original design basis. Determination of the component failure load is useful for this type of evaluation. This paper presents criteria based upon strain limits to predict the load at failure. The failure modes addressed are excessive plastic deformations, localized plastic strains, and structural instability. The effects of analytical method sophistication, as built configurations, material properties degradation, and stress state are addressed by the criteria

  20. Deformation strain inhomogeneity in columnar grain nickel

    Wu, G.L.; Godfrey, A.; Juul Jensen, D.

    2005-01-01

    A method is presented for determination of the local deformation strain of individual grains in the bulk of a columnar grain sample. The method, based on measurement of the change in grain area of each grain, is applied to 12% cold rolled nickel. Large variations are observed in the local strain...... associated with each grain. (c) 2005 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved....

  1. Antimicrobial properties of indigenous Lactobacillus sakei strain

    Vesković-Moračanin Slavica; Obradović D.; Velebit B.; Borović Branka; Škrinjar Marija; Turubatović L.

    2010-01-01

    The strain I 154 of Lactobacillus sakei has been isolated from traditionally fermented sausages in the course of the realization of the international project (INCO PROJECT No ICA4-CT-2002-10037). This strain exhibited the ability for bacteriocin production. Antimicrobial properties of the isolated bacteriocin (sakacine), its sensibility towards proteolytic enzymes, as well as the effect of increased to high temperatures on its stability have been examined in this work. Semi purified bacterioc...

  2. A closer look at prion strains

    Solforosi, Laura; Milani, Michela; Mancini, Nicasio; Clementi, Massimo; Burioni, Roberto

    2013-01-01

    Prions are infectious proteins that are responsible for transmissible spongiform encephalopathies (TSEs) and consist primarily of scrapie prion protein (PrPSc), a pathogenic isoform of the host-encoded cellular prion protein (PrPC). The absence of nucleic acids as essential components of the infectious prions is the most striking feature associated to these diseases. Additionally, different prion strains have been isolated from animal diseases despite the lack of DNA or RNA molecules. Mounting evidence suggests that prion-strain-specific features segregate with different PrPSc conformational and aggregation states. Strains are of practical relevance in prion diseases as they can drastically differ in many aspects, such as incubation period, PrPSc biochemical profile (e.g., electrophoretic mobility and glycoform ratio) and distribution of brain lesions. Importantly, such different features are maintained after inoculation of a prion strain into genetically identical hosts and are relatively stable across serial passages. This review focuses on the characterization of prion strains and on the wide range of important implications that the study of prion strains involves. PMID:23357828

  3. Instrument for measuring fuel cladding strain

    Billeter, T.R.

    1976-01-01

    Development work to provide instrumentation for the continuous measurement of strain of material specimens such as nuclear fuel cladding has shown that a microwave sensor and associated instrumentation hold promise. The cylindrical sensor body enclosing the specimen results in a coaxial resonator absorbing microwave energy at frequencies dependent upon the diameter of the specimen. Diametral changes of a microinch can be resolved with use of the instrumentation. Very reasonable values of elastic strain were measured at 75 0 F and 1000 0 F for an internally pressurized 20 percent C.W. 316 stainless steel specimen simulating nuclear fuel cladding. The instrument also indicated the creep strain of the same specimen pressurized at 6500 psi and at a temperature of 1000 0 F for a period of 700 hours. Although the indicated strain appears greater than actual, the sensor/specimen unit experienced considerable oxidation even though an inert gas purge persisted throughout the test duration. By monitoring at least two modes of resonance, the measured strain was shown to be nearly independent of sensor temperature. To prevent oxidation, a second test was performed in which the specimen/sensor units were contained in an evacuated enclosure. The strain of the two prepressurized specimens as indicated by the microwave instrumentation agreed very closely with pre- and post-test measurements obtained with use of a laser interferometer

  4. Strain-controlled electrocatalysis on multimetallic nanomaterials

    Luo, Mingchuan; Guo, Shaojun

    2017-11-01

    Electrocatalysis is crucial for the development of clean and renewable energy technologies, which may reduce our reliance on fossil fuels. Multimetallic nanomaterials serve as state-of-the-art electrocatalysts as a consequence of their unique physico-chemical properties. One method of enhancing the electrocatalytic performance of multimetallic nanomaterials is to tune or control the surface strain of the nanomaterials, and tremendous progress has been made in this area in the past decade. In this Review, we summarize advances in the introduction, tuning and quantification of strain in multimetallic nanocrystals to achieve more efficient energy conversion by electrocatalysis. First, we introduce the concept of strain and its correlation with other key physico-chemical properties. Then, using the electrocatalytic reduction of oxygen as a model reaction, we discuss the underlying mechanisms behind the strain-adsorption-reactivity relationship based on combined classical theories and models. We describe how this knowledge can be harnessed to design multimetallic nanocrystals with optimized strain to increase the efficiency of oxygen reduction. In particular, we highlight the unexpectedly beneficial (and previously overlooked) role of tensile strain from multimetallic nanocrystals in improving electrocatalysis. We conclude by outlining the challenges and offering our perspectives on the research directions in this burgeoning field.

  5. Strain rate measurement by Electronic Speckle Pattern Interferometry: A new look at the strain localization onset

    Guelorget, Bruno; Francois, Manuel; Vial-Edwards, Cristian; Montay, Guillaume; Daniel, Laurent; Lu, Jian

    2006-01-01

    In-plane Electronic Speckle Pattern Interferometry has been successfully used during tensile testing of semi-hard copper sheets in order to measure the strain rate. On one hand, heterogeneity in strain rate field has been found before the maximum of the tensile force (ε t ≅ 19.4 and 25.4%, respectively). Thus, a localization phenomenon occurs before the classic Considere's criterion (dF = 0) for the diffuse neck initiation. On the other hand, strain rate measurement before fracture shows the moment where one of the two slip band systems becomes predominant, then strain concentrates in a small area, the shear band. Uncertainty evaluation has been carried out, which shows a very good accuracy of the total strain and the strain rate measurements

  6. Strain rate measurement by Electronic Speckle Pattern Interferometry: A new look at the strain localization onset

    Guelorget, Bruno [Universite de Technologie de Troyes (UTT), Laboratoire des Systemes Mecaniques et d' ingenierie Simultanee (LASMIS, CNRS FRE 2719), 12 rue Marie Curie, B.P. 2060, 10010 Troyes Cedex (France)]. E-mail: bruno.guelorget@utt.fr; Francois, Manuel [Universite de Technologie de Troyes (UTT), Laboratoire des Systemes Mecaniques et d' ingenierie Simultanee (LASMIS, CNRS FRE 2719), 12 rue Marie Curie, B.P. 2060, 10010 Troyes Cedex (France); Vial-Edwards, Cristian [Departemento de Ingenieria Mecanica y Metalurgica, Pontificia Universidad Catolica de Chile, Vicuna Mackenna 4860, 6904411 Santiago (Chile); Montay, Guillaume [Universite de Technologie de Troyes (UTT), Laboratoire des Systemes Mecaniques et d' ingenierie Simultanee (LASMIS, CNRS FRE 2719), 12 rue Marie Curie, B.P. 2060, 10010 Troyes Cedex (France); Daniel, Laurent [Universite de Technologie de Troyes (UTT), Laboratoire des Systemes Mecaniques et d' ingenierie Simultanee (LASMIS, CNRS FRE 2719), 12 rue Marie Curie, B.P. 2060, 10010 Troyes Cedex (France); Lu, Jian [Universite de Technologie de Troyes (UTT), Laboratoire des Systemes Mecaniques et d' ingenierie Simultanee (LASMIS, CNRS FRE 2719), 12 rue Marie Curie, B.P. 2060, 10010 Troyes Cedex (France)

    2006-01-15

    In-plane Electronic Speckle Pattern Interferometry has been successfully used during tensile testing of semi-hard copper sheets in order to measure the strain rate. On one hand, heterogeneity in strain rate field has been found before the maximum of the tensile force ({epsilon} {sup t} {approx_equal} 19.4 and 25.4%, respectively). Thus, a localization phenomenon occurs before the classic Considere's criterion (dF = 0) for the diffuse neck initiation. On the other hand, strain rate measurement before fracture shows the moment where one of the two slip band systems becomes predominant, then strain concentrates in a small area, the shear band. Uncertainty evaluation has been carried out, which shows a very good accuracy of the total strain and the strain rate measurements.

  7. Molecular typing of Brucella melitensis endemic strains and differentiation from the vaccine strain Rev-1.

    Noutsios, Georgios T; Papi, Rigini M; Ekateriniadou, Loukia V; Minas, Anastasios; Kyriakidis, Dimitrios A

    2012-03-01

    In the present study forty-four Greek endemic strains of Br. melitensis and three reference strains were genotyped by Multi locus Variable Number Tandem Repeat (ML-VNTR) analysis based on an eight-base pair tandem repeat sequence that was revealed in eight loci of Br. melitensis genome. The forty-four strains were discriminated from the vaccine strain Rev-1 by Restriction Fragment Length Polymorphism (RFLP) and Denaturant Gradient Gel Electrophoresis (DGGE). The ML-VNTR analysis revealed that endemic, reference and vaccine strains are genetically closely related, while most of the loci tested (1, 2, 4, 5 and 7) are highly polymorphic with Hunter-Gaston Genetic Diversity Index (HGDI) values in the range of 0.939 to 0.775. Analysis of ML-VNTRs loci stability through in vitro passages proved that loci 1 and 5 are non stable. Therefore, vaccine strain can be discriminated from endemic strains by allele's clusters of loci 2, 4, 6 and 7. RFLP and DGGE were also employed to analyse omp2 gene and reveled different patterns among Rev-1 and endemic strains. In RFLP, Rev-1 revealed three fragments (282, 238 and 44 bp), while endemic strains two fragments (238 and 44 bp). As for DGGE, the electrophoretic mobility of Rev-1 is different from the endemic strains due to heterologous binding of DNA chains of omp2a and omp2b gene. Overall, our data show clearly that it is feasible to genotype endemic strains of Br. melitensis and differentiate them from vaccine strain Rev-1 with ML-VNTR, RFLP and DGGE techniques. These tools can be used for conventional investigations in brucellosis outbreaks.

  8. Strain-dependent diffusion behavior of H within tungsten

    Ding, Wenyi; He, Haiyan; Liu, Changsong; Ding, Rui; Chen, Junling; Pan, Bicai

    2014-01-01

    The diffusion behaviors of H in tungsten, a promising material serving as the first wall facing the plasma in nuclear reactors, under either biaxial strain or isotropic strain are theoretically studied. We find that under the isotropic strain, an individual H atom may diffuse along all pathways, and under the biaxial strain, it preferably migrates along the direction perpendicular to the loaded strain. Moreover, in the case of either the isotropic or the biaxial strain, the loaded compressive strain weakens the diffusion of H, while the loaded tensile strain enhances the diffusion of H in bulk W.

  9. Strain-dependent diffusion behavior of H within tungsten

    Ding, Wenyi; He, Haiyan [Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Liu, Changsong [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, P.O. Box 1129, Hefei 230031 (China); Ding, Rui; Chen, Junling [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Pan, Bicai, E-mail: bcpan@ustc.edu.cn [Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Hefei National Laboratory for Physical Science at Microscale, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2014-06-15

    The diffusion behaviors of H in tungsten, a promising material serving as the first wall facing the plasma in nuclear reactors, under either biaxial strain or isotropic strain are theoretically studied. We find that under the isotropic strain, an individual H atom may diffuse along all pathways, and under the biaxial strain, it preferably migrates along the direction perpendicular to the loaded strain. Moreover, in the case of either the isotropic or the biaxial strain, the loaded compressive strain weakens the diffusion of H, while the loaded tensile strain enhances the diffusion of H in bulk W.

  10. Information about the Current Strain of Clostridium difficile

    ... fluoroquinolones may provide the new strain with an advantage over susceptible strains to spread within healthcare facilities where these antibiotics are commonly used. Top of page What should ...

  11. Effects of strain on the Schwinger pair creation in graphene

    Fanbanrai, P.; Hutem, A.; Boonchui, S.

    2015-01-01

    The effects of strain on mechanically deformed graphene are determined by looking at how the strain affects the amplitude of the Schwinger two particle pair state. The influences of the lattice distortions, such as isotropic tensile strain ϵ is , shear strain ϵ ss , uniaxial armchair strain ϵ as , and zigzag strain ϵ zs , on the photon emission spectrum have been analyzed. We find that the intensities of the emission increases or decreases when compared to those of the unstrained graphene, depending on the type of strain applied. Thus the structure of energy band, the frequencies of the photons and the emission spectrum can be controlled by use of the different strains

  12. Intramyocardial strain estimation from cardiac cine MRI.

    Elnakib, Ahmed; Beache, Garth M; Gimel'farb, Georgy; El-Baz, Ayman

    2015-08-01

    Functional strain is one of the important clinical indicators for the quantification of heart performance and the early detection of cardiovascular diseases, and functional strain parameters are used to aid therapeutic decisions and follow-up evaluations after cardiac surgery. A comprehensive framework for deriving functional strain parameters at the endocardium, epicardium, and mid-wall of the left ventricle (LV) from conventional cine MRI data was developed and tested. Cine data were collected using short TR-/TE-balanced steady-state free precession acquisitions on a 1.5T Siemens Espree scanner. The LV wall borders are segmented using a level set-based deformable model guided by a stochastic force derived from a second-order Markov-Gibbs random field model that accounts for the object shape and appearance features. Then, the mid-wall of the segmented LV is determined based on estimating the centerline between the endocardium and epicardium of the LV. Finally, a geometrical Laplace-based method is proposed to track corresponding points on successive myocardial contours throughout the cardiac cycle in order to characterize the strain evolutions. The method was tested using simulated phantom images with predefined point locations of the LV wall throughout the cardiac cycle. The method was tested on 30 in vivo datasets to evaluate the feasibility of the proposed framework to index functional strain parameters. The cine MRI-based model agreed with the ground truth for functional metrics to within 0.30 % for indexing the peak systolic strain change and 0.29 % (per unit time) for indexing systolic and diastolic strain rates. The method was feasible for in vivo extraction of functional strain parameters. Strain indexes of the endocardium, mid-wall, and epicardium can be derived from routine cine images using automated techniques, thereby improving the utility of cine MRI data for characterization of myocardial function. Unlike traditional texture-based tracking, the

  13. Internal strain evolution during heating of Ti-6Al-4V/SCS-6 composite

    Choo, H.; Rangaswamy, P.; Bourke, M.A.M.

    1999-01-01

    The characteristics of the residual stresses and their effects on the properties in continuous SiC fiber reinforced Ti-6Al-4V matrix composites (TMCs) have been extensively studied. However, to date, few experimental studies (e.g. Ti-14Al-21Nb/SCS-6) have characterized the thermal residual strain in TMCs at elevated temperatures. Therefore, the authors investigated the evolution of the thermal residual strain during heating of Ti-6Al-4V/35vol% SiC composite. In this study the authors used in situ high temperature neutron diffraction to measure strains: (1) in the matrix (α and β phases) and in the fiber, (2) for several lattice reflections in each phase and (3) from both axial and the transverse directions. One distinguishing feature is the wide temperature range (from room temperature up to 1,170K) over which the study was performed. Although the proposed application temperature is typically less than 800K, TMCs are subject to higher temperatures during fabrication and may experience high temperature excursions while in service. Therefore, the authors extended the study to the high temperature regime where the matrix starts to undergo a phase transformation between αminus and βminusTi. Measurements from this regime (800approximately1,170K) provide insights on; (1) the inelastic relaxation of the residual strains through matrix yielding and creep, (2) the effect of the phase transformation on the residual strains and (3) the effect of the presence of SiC on the matrix phase evolution

  14. Effects of the Strain Rate Sensitivity and Strain Hardening on the Saturated Impulse of Plates

    Ling Zhu

    Full Text Available Abstract This paper studies the stiffening effects of the material strain rate sensitivity and strain hardening on the saturated impulse of elastic, perfectly plastic plates. Finite element (FE code ABAQUS is employed to simulate the elastoplastic response of square plates under rectangular pressure pulse. Rigid-plastic analyses for saturated impulse, which consider strain rate sensitivity and strain hardening, are conducted. Satisfactory agreement between the finite element models (FEM and predictions of the rigid-plastic analysis is obtained, which verifies that the proposed rigid-plastic methods are effective to solve the problem including strain rate sensitivity and strain hardening. The quantitative results for the scale effect of the strain rate sensitivity are given. The results for the stiffening effects suggest that two general stiffening factors n 1 and n 2, which characterizes the strain rate sensitivity and strain hardening effect, respectively can be defined. The saturated displacement is inversely proportional to the stiffening factors (i.e. n 1 and n 2 and saturated impulse is inversely proportional to the square roots of the stiffening factors (i.e. n 1 and n 2. Formulae for displacement and saturated impulse are proposed based on the empirical analysis.

  15. Genome-Wide Transcription Study of Cryptococcus neoformans H99 Clinical Strain versus Environmental Strains.

    Elaheh Movahed

    Full Text Available The infection of Cryptococcus neoformans is acquired through the inhalation of desiccated yeast cells and basidiospores originated from the environment, particularly from bird's droppings and decaying wood. Three environmental strains of C. neoformans originated from bird droppings (H4, S48B and S68B and C. neoformans reference clinical strain (H99 were used for intranasal infection in C57BL/6 mice. We showed that the H99 strain demonstrated higher virulence compared to H4, S48B and S68B strains. To examine if gene expression contributed to the different degree of virulence among these strains, a genome-wide microarray study was performed to inspect the transcriptomic profiles of all four strains. Our results revealed that out of 7,419 genes (22,257 probes examined, 65 genes were significantly up-or down-regulated in H99 versus H4, S48B and S68B strains. The up-regulated genes in H99 strain include Hydroxymethylglutaryl-CoA synthase (MVA1, Mitochondrial matrix factor 1 (MMF1, Bud-site-selection protein 8 (BUD8, High affinity glucose transporter 3 (SNF3 and Rho GTPase-activating protein 2 (RGA2. Pathway annotation using DAVID bioinformatics resource showed that metal ion binding and sugar transmembrane transporter activity pathways were highly expressed in the H99 strain. We suggest that the genes and pathways identified may possibly play crucial roles in the fungal pathogenesis.

  16. Variation in the strain anisotropy of Zircaloy with temperature and strain

    Hindle, E.D.; Worswick, D.

    1984-04-01

    Strain anisotropy was investigated at temperatures in the range 293 to 1117K in circular tensile specimens prepared from rolled Zircaloy-2 plate so that their tensile axes were parallel to and transverse to the rolling direction. The strain anisotropy factor for both types of specimen increased markedly in the high alpha phase region above 923K reaching a maximum at circa 1070K. Above this temperature in the alpha-plus-beta phase region the strain anisotropy decreased rapidly as the proportion of beta phase increased and was almost non-existent at 1173K. The strain anisotropy was markedly strain dependent, particularly in the high alpha phase region. The study was extended to Zircaloy-4 pressurized water reactor (PWR) 17 x 17 type fuel rod tubing specimens which were strained under biaxial conditions using cooling conditions which promoted uniform diametral strain over most of their lengths (circa 250 mm). In these circumstances the strain anisotropy is manifest by a reduction in length. Measurement of this change along with that in diameter and wall thickness produced data from which the strain anisotropy factor was calculated. The results, although influenced by additional factors discussed in the paper, were similar to those observed in the uniaxial Zircaloy-2 tensile tests. (author)

  17. An ultrasensitive strain sensor with a wide strain range based on graphene armour scales.

    Yang, Yi-Fan; Tao, Lu-Qi; Pang, Yu; Tian, He; Ju, Zhen-Yi; Wu, Xiao-Ming; Yang, Yi; Ren, Tian-Ling

    2018-06-12

    An ultrasensitive strain sensor with a wide strain range based on graphene armour scales is demonstrated in this paper. The sensor shows an ultra-high gauge factor (GF, up to 1054) and a wide strain range (ε = 26%), both of which present an advantage compared to most other flexible sensors. Moreover, the sensor is developed by a simple fabrication process. Due to the excellent performance, this strain sensor can meet the demands of subtle, large and complex human motion monitoring, which indicates its tremendous application potential in health monitoring, mechanical control, real-time motion monitoring and so on.

  18. An incremental analysis of a deep drawing steel’s material behaviour undergoing the predeformation using drawbeads

    Schmid, H.; Suttner, S.; Merklein, M.

    2017-09-01

    Nowadays lightweight design in metal forming processes leads to complex deep drawing geometries, which can cause multiple damages. Therefore, drawbeads are one way to regulate and control material flow during the forming process. Not only in research, but also in industrial practice, it could be determined that material is work hardened passing drawbead geometries. It particularly means when material is pre-deformed with tensile and alternating bending loads. This incident also gives the opportunity to utilize it in a reasonable way if examined properly. To investigate these findings, a process oriented and comprehensive analysis of the material behaviour during these forming operations is needed. In this paper, sheet metal strips are linearly drawn through a drawbead and stopped after passing the drawbead. Within this forming operation, the material undergoes non-linear straining before reaching the in-plane position again. Here, the process will be stopped to investigate a permanent strengthening local along the sheet thickness. Therefore, microhardness measurements are realized before and after passing the drawbead. Because of its common use and its wide known material data, a deep drawing steel DC will be used for these studies. Additionally, the strategy is applied to advanced high strength steel.

  19. Spectral entropy monitoring for adults and children undergoing general anaesthesia.

    Chhabra, Anjolie; Subramaniam, Rajeshwari; Srivastava, Anurag; Prabhakar, Hemanshu; Kalaivani, Mani; Paranjape, Saloni

    2016-03-14

    (BIS) monitor was used to assess anaesthetic depth. We used standard methodological procedures expected by Cochrane. Two review authors independently extracted details of trial methodology and outcome data from trials considered eligible for inclusion. All analyses were made on an intention-to-treat basis. We used a random-effect model where there was heterogeneity. For assessments of the overall quality of evidence for each outcome that included pooled data from RCTs, we downgraded evidence from 'high quality' by one level for serious (or by two for very serious) study limitations (risk of bias, indirectness of evidence, serious inconsistency, imprecision of effect or potential publication bias). We included 11 RCTs (962 participants). Eight RCTs (762 participants) were carried out on adults (18 to 80 years of age), two (128 participants) involved children (two to 16 years) and one RCT (72 participants) included patients aged 60 to 75 years. Of the 11 included studies, we judged three to be at low risk of bias, and the remaining eight RCTs at unclear or high risk of bias.Six RCTs (383 participants) estimated the primary outcome, time to awakening after stopping general anaesthesia, which was reduced in the entropy as compared to the standard practice group (mean difference (MD) -5.42 minutes, 95% confidence interval (CI) -8.77 to -2.08; moderate quality of evidence). We noted heterogeneity for this outcome; on performing subgroup analysis this was found to be due to studies that included participants undergoing major, long duration surgeries (off-pump coronary artery bypass grafting, major urological surgery). The MD for time to awakening with four studies on ambulatory procedures was -3.20 minutes (95% CI -3.94 to -2.45). No trial reported the second primary outcome, mortality at 24 hours, 30 days, and one year with the use of entropy monitoring.Eight trials (797 participants) compared the secondary outcome, postoperative recall of intraoperative events (awareness

  20. CLINICAL AND PHARMACOECONOMIC REASONABILITY OF USING PROBIOTIC ENTEROCOCCUS STRAIN FOR THE COMPLEX DEVELOPMENTAL CARE PROGRAM FOR PREMATURE INFANTS

    N. V. Gonchar

    2015-01-01

    Full Text Available Introduction. Possibilities of using probiotic enterococci in premature neonates undergoing inpatient antibacterial therapy remains understudied. The article is aimed at analyzing clinical and pharmacoeconomic reasonability of using probiotic Enterococcus faecium L3 strain in premature infants with very low body weight in the framework of complex inpatient developmental care. Patients and methods. 55 children randomized into 2 groups were observed: the control group (n = 26 was undergoing standard developmental care program, the primary group (n = 29 was introduced liquid probiotic Enterococcus faecium L3 strain (titer — 108 CFU/ml or more (0.5 ml TID for 14 days after attaining the enteral feeding volume of 5.0 ml. Results. Analysis of the clinical symptoms characteristic of non-smooth course of developmental care over premature infants helped to reveal higher frequency of infectious complications in the control group children than in the primary group (14 [53.8%] vs. 6 [20.7%]; p < 0.05. Acute food intolerance was observed less frequently in the primary group than in the control group (6 [20.7%] vs. 10 [38.5%], p > 0.05. The primary group's children featured significant decrease in the frequency of monocytosis, positive changes of intestinal microbiotic composition (increase in the amount of bifidum bacteria, lactobacilli, enterococci, decrease in the amount of Clostridium difficile and antibiotic-resistant clinical Klebsiella pneumoniae strains. Conclusion. Favorable outcome of developmental care over premature infants (absence of infectious complications was less expensive in the primary group's children.

  1. Time-lapse seismic waveform modelling and attribute analysis using hydromechanical models for a deep reservoir undergoing depletion

    He, Y.-X.; Angus, D. A.; Blanchard, T. D.; Wang, G.-L.; Yuan, S.-Y.; Garcia, A.

    2016-04-01

    Extraction of fluids from subsurface reservoirs induces changes in pore pressure, leading not only to geomechanical changes, but also perturbations in seismic velocities and hence observable seismic attributes. Time-lapse seismic analysis can be used to estimate changes in subsurface hydromechanical properties and thus act as a monitoring tool for geological reservoirs. The ability to observe and quantify changes in fluid, stress and strain using seismic techniques has important implications for monitoring risk not only for petroleum applications but also for geological storage of CO2 and nuclear waste scenarios. In this paper, we integrate hydromechanical simulation results with rock physics models and full-waveform seismic modelling to assess time-lapse seismic attribute resolution for dynamic reservoir characterization and hydromechanical model calibration. The time-lapse seismic simulations use a dynamic elastic reservoir model based on a North Sea deep reservoir undergoing large pressure changes. The time-lapse seismic traveltime shifts and time strains calculated from the modelled and processed synthetic data sets (i.e. pre-stack and post-stack data) are in a reasonable agreement with the true earth models, indicating the feasibility of using 1-D strain rock physics transform and time-lapse seismic processing methodology. Estimated vertical traveltime shifts for the overburden and the majority of the reservoir are within ±1 ms of the true earth model values, indicating that the time-lapse technique is sufficiently accurate for predicting overburden velocity changes and hence geomechanical effects. Characterization of deeper structure below the overburden becomes less accurate, where more advanced time-lapse seismic processing and migration is needed to handle the complex geometry and strong lateral induced velocity changes. Nevertheless, both migrated full-offset pre-stack and near-offset post-stack data image the general features of both the overburden and

  2. Dynamic strains for earthquake source characterization

    Barbour, Andrew J.; Crowell, Brendan W

    2017-01-01

    Strainmeters measure elastodynamic deformation associated with earthquakes over a broad frequency band, with detection characteristics that complement traditional instrumentation, but they are commonly used to study slow transient deformation along active faults and at subduction zones, for example. Here, we analyze dynamic strains at Plate Boundary Observatory (PBO) borehole strainmeters (BSM) associated with 146 local and regional earthquakes from 2004–2014, with magnitudes from M 4.5 to 7.2. We find that peak values in seismic strain can be predicted from a general regression against distance and magnitude, with improvements in accuracy gained by accounting for biases associated with site–station effects and source–path effects, the latter exhibiting the strongest influence on the regression coefficients. To account for the influence of these biases in a general way, we include crustal‐type classifications from the CRUST1.0 global velocity model, which demonstrates that high‐frequency strain data from the PBO BSM network carry information on crustal structure and fault mechanics: earthquakes nucleating offshore on the Blanco fracture zone, for example, generate consistently lower dynamic strains than earthquakes around the Sierra Nevada microplate and in the Salton trough. Finally, we test our dynamic strain prediction equations on the 2011 M 9 Tohoku‐Oki earthquake, specifically continuous strain records derived from triangulation of 137 high‐rate Global Navigation Satellite System Earth Observation Network stations in Japan. Moment magnitudes inferred from these data and the strain model are in agreement when Global Positioning System subnetworks are unaffected by spatial aliasing.

  3. Multiscale segmentation-aided digital image correlation for strain concentration characterization of a turbine blade fir-tree root

    Sun, Chen; Zhou, Yihao; Li, Yang; Chen, Jubing; Miao, Hong

    2018-04-01

    In this paper, a multiscale segmentation-aided digital image correlation method is proposed to characterize the strain concentration of a turbine blade fir-tree root during its contact with the disk groove. A multiscale approach is implemented to increase the local spatial resolution, as the strain concentration area undergoes highly non-uniform deformation and its size is much smaller than the contact elements. In this approach, a far-field view and several near-field views are selected, aiming to get the full-field deformation and local deformation simultaneously. To avoid the interference of different cameras, only the optical axis of the far-field camera is selected to be perpendicular to the specimen surface while the others are inclined. A homography transformation is optimized by matching the feature points, to rectify the artificial deformation caused by the inclination of the optical axis. The resultant genuine near-field strain is thus obtained after the transformation. A real-world experiment is carried out and the strain concentration is characterized. The strain concentration factor is defined accordingly to provide a quantitative analysis.

  4. Strain preservation of experimental animals: vitrification of two-cell stage embryos for multiple mouse strains.

    Eto, Tomoo; Takahashi, Riichi; Kamisako, Tsutomu

    2015-04-01

    Strain preservation of experimental animals is crucial for experimental reproducibility. Maintaining complete animal strains, however, is costly and there is a risk for genetic mutations as well as complete loss due to disasters or illness. Therefore, the development of effective vitrification techniques for cryopreservation of multiple experimental animal strains is important. We examined whether a vitrification method using cryoprotectant solutions, P10 and PEPeS, is suitable for preservation of multiple inbred and outbred mouse strains. First, we investigated whether our vitrification method using cryoprotectant solutions was suitable for two-cell stage mouse embryos. In vitro development of embryos exposed to the cryoprotectant solutions was similar to that of fresh controls. Further, the survival rate of the vitrified embryos was extremely high (98.1%). Next, we collected and vitrified two-cell stage embryos of 14 mouse strains. The average number of embryos obtained from one female was 7.3-33.3. The survival rate of vitrified embryos ranged from 92.8% to 99.1%, with no significant differences among mouse strains. In vivo development did not differ significantly between fresh controls and vitrified embryos of each strain. For strain preservation using cryopreserved embryos, two offspring for inbred lines and one offspring for outbred lines must be produced from two-cell stage embryos collected from one female. The expected number of surviving fetuses obtained from embryos collected from one female of either the inbred or outbred strains ranged from 2.9 to 19.5. The findings of the present study indicated that this vitrification method is suitable for strain preservation of multiple mouse strains. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  5. Mycobacterium tuberculosis strains exhibit differential and strain-specific molecular signatures in pulmonary epithelial cells.

    Mvubu, Nontobeko Eunice; Pillay, Balakrishna; Gamieldien, Junaid; Bishai, William; Pillay, Manormoney

    2016-12-01

    Although pulmonary epithelial cells are integral to innate and adaptive immune responses during Mycobacterium tuberculosis infection, global transcriptomic changes in these cells remain largely unknown. Changes in gene expression induced in pulmonary epithelial cells infected with M. tuberculosis F15/LAM4/KZN, F11, F28, Beijing and Unique genotypes were investigated by RNA sequencing (RNA-Seq). The Illumina HiSeq 2000 platform generated 50 bp reads that were mapped to the human genome (Hg19) using Tophat (2.0.10). Differential gene expression induced by the different strains in infected relative to the uninfected cells was quantified and compared using Cufflinks (2.1.0) and MeV (4.0.9), respectively. Gene expression varied among the strains with the total number of genes as follows: F15/LAM4/KZN (1187), Beijing (1252), F11 (1639), F28 (870), Unique (886) and H37Rv (1179). A subset of 292 genes was commonly induced by all strains, where 52 genes were down-regulated while 240 genes were up-regulated. Differentially expressed genes were compared among the strains and the number of induced strain-specific gene signatures were as follows: F15/LAM4/KZN (138), Beijing (52), F11 (255), F28 (55), Unique (186) and H37Rv (125). Strain-specific molecular gene signatures associated with functional pathways were observed only for the Unique and H37Rv strains while certain biological functions may be associated with other strain signatures. This study demonstrated that strains of M. tuberculosis induce differential gene expression and strain-specific molecular signatures in pulmonary epithelial cells. Specific signatures induced by clinical strains of M. tuberculosis can be further explored for novel host-associated biomarkers and adjunctive immunotherapies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Anisotropic nature of radially strained metal tubes

    Strickland, Julie N.

    Metal pipes are sometimes swaged by a metal cone to enlarge them, which increases the strain in the material. The amount of strain is important because it affects the burst and collapse strength. Burst strength is the amount of internal pressure that a pipe can withstand before failure, while collapse strength is the amount of external pressure that a pipe can withstand before failure. If the burst or collapse strengths are exceeded, the pipe may fracture, causing critical failure. Such an event could cost the owners and their customers millions of dollars in clean up, repair, and lost time, in addition to the potential environmental damage. Therefore, a reliable way of estimating the burst and collapse strength of strained pipe is desired and valuable. The sponsor currently rates strained pipes using the properties of raw steel, because those properties are easily measured (for example, yield strength). In the past, the engineers assumed that the metal would be work-hardened when swaged, so that yield strength would increase. However, swaging introduces anisotropic strain, which may decrease the yield strength. This study measured the yield strength of strained material in the transverse and axial direction and compared them to raw material, to determine the amount of anisotropy. This information will be used to more accurately determine burst and collapse ratings for strained pipes. More accurate ratings mean safer products, which will minimize risk for the sponsor's customers. Since the strained metal has a higher yield strength than the raw material, using the raw yield strength to calculate burst and collapse ratings is a conservative method. The metal has even higher yield strength after strain aging, which indicates that the stresses are relieved. Even with the 12% anisotropy in the strained and 9% anisotropy in the strain aged specimens, the raw yield strengths are lower and therefore more conservative. I recommend that the sponsor continue using the raw

  7. Topical versus caudal ketamine/bupivacaine combination for postoperative analgesia in children undergoing inguinal herniotomy

    Hala Saad Abdel-Ghaffar

    2017-01-01

    Conclusion: Wound instillation of bupivacaine/ketamine is a simple, noninvasive, and effective technique that could be a safe alternative to CK for postoperative analgesia in children undergoing inguinal hernia repair.

  8. Pseudo-outbreak of pseudomonas aeruginosa in HIV-infected patients undergoing fiberoptic bronchoscopy

    Kolmos, H J; Lerche, A; Kristoffersen, Kirsten Lydia

    1994-01-01

    Pseudomonas aeruginosa was isolated from bronchoalveolar lavage fluid from 8 consecutive patients undergoing bronchoscopy at an infectious diseases unit. None of the patients developed signs of respiratory tract infection that could be ascribed to the organism. The source of contamination...

  9. Evaluation of pulmonary function in renal transplant recipients and chronic renal failure patients undergoing maintenance hemodialysis

    Mohamed E. Abdalla

    2013-01-01

    Conclusion: There is impairment of lung function in patients with CRF undergoing hemodialysis. The main changes are small airway obstruction, reduction in carbon monoxide transfer and diminished 6MWT that were not completely improved in the kidney transplant patients.

  10. Perioperative glycemic control in diabetic patients undergoing coronary artery bypass graft surgery

    Ehab A. Wahby

    2016-08-01

    Conclusion: Tight glycemic control improved perioperative outcome in diabetic CABG patients. Maintaining perioperative blood glucose level between 110 and 149 mg/dl is safe and should be recommended as a routine practice in diabetic patients undergoing CABG surgery.

  11. Perioperative volume replacement in children undergoing cardiac surgery: albumin versus hydroxyethyl starch 130/0.4

    Hanart, Christophe; Khalife, Maher; de Villé, Andrée; Otte, Florence; de Hert, Stefan; van der Linden, Philippe

    2009-01-01

    OBJECTIVE: To compare 4% albumin with 6% hydroxyethyl starch (HES) 130/0.4 in terms of perioperative blood loss and intraoperative fluid requirements in children undergoing cardiac surgery. DESIGN: Prospective randomized study. SETTING: Single University Hospital. PATIENTS: Pediatric patients

  12. Interaction of Microbiology and Pathology in Women Undergoing Investigations for Infertility

    Joseph Debattista

    2004-01-01

    asymptomatic women undergoing investigation of infertility were correlated with the outcomes of microbiological screening for Chlamydia trachomatis, Mycoplasma pneumoniae, Mycoplasma hominis, ureaplasma species, Neisseria gonorrhoeae, Neisseria meningitidis and Chlamydia pneumoniae.

  13. Mid-term outcomes of patients undergoing adjustable pulmonary artery banding

    Sachin Talwar

    2016-01-01

    Conclusions: Patients undergoing APAB fulfilled the desired objectives of the pulmonary artery banding (PAB with minimum PA complications in the mid-term. This added to the early postoperative benefits, makes the APAB an attractive alternative to the CPAB.

  14. Stevens Johnson Syndrome in a patient undergoing gynaecological brachytherapy: An association or an incident?

    Ferreira, M. R.; Amado, A.; Jorge, M.; Grillo, I. M.

    2011-01-01

    Background: Stevens Johnson Syndrome and Erythema Multiforme are hypersensitivity skin reactions generally arising in the context of multiple causes. Radiation therapy is considered to be one of these causes, although most reports are hindered by concomitant medications. Aim: The aim of this paper was to present a case of Stevens Johnson Syndrome arising in a patient undergoing gynaecological brachytherapy with an unusual presentation. Case:We describe a case of a 56-year-old woman with endometrial cancer undergoing adjuvant gynaecological radiotherapy. While undergoing a gynaecological brachytherapy boost, she developed bilateral conjunctivitis that progressed to oral mucositis and pruritic erythema with sloughing of the skin on her arms and legs but not the torso or irradiated fields (namely the vaginal mucosa). Conclusion: This case illustrates the association of RT/SJS; however, it also raises the question of patients undergoing RT being more susceptible to SJS as opposed to a direct cause of the disease. (authors)

  15. Investigating the motives of patients with knee OA undergoing a TKR

    Traumer, Line; Sørensen, Erik Elgaard; Kusk, Kathrine Hoffmann

    2018-01-01

    , a qualitatively assessment of what actually affects the patient's decision to undergo TKR would be important. Therefore, the purpose of this study was to investigate the motives of patients with knee OA choosing to undergo TKR and to explore the factors considered important during their decision?making process...... was a legitimate argument among patients. The prospect of avoiding taking high doses of pain?relieving medication and hearing positive experiences of others who had undergone TKR motivated patients to undergo TKR. However, negative experiences of others were neglected. Conclusions Patients' decision?making process...... revealed that the interaction between doctor and patient emerged as a factor highly influential on patients' decision?making process with patients choosing the treatment option suggested by the doctor. Using x?rays, revealing no cartilage between the bones, as a reason for choosing to undergo TKR...

  16. Anaesthesia in patients undergoing esophago-gastro-duodenoscopy for suspected bleeding

    Helsø, Ida; Risom, Martin; Vestergaard, Therese Risom

    2017-01-01

    INTRODUCTION: Upper gastrointestinal bleeding (UGIB) is a common emergency. Currently, there are no agreed guidelines on the level of anaesthetic support required in patients undergoing acute esophago-gastro-duodendoscopy (EGD). METHODS: An online questionnaire comprising 19 questions...

  17. Willingness to undergo HIV testing in the Kintampo districts of Ghana

    Willingness to undergo HIV testing in the Kintampo districts of Ghana. ... Journal Home > Vol 48, No 1 (2014) > ... Objective: An HIV module was incorporated into the routine survey of the Kintampo Health and Demographic Surveillance ...

  18. Can shared care deliver better outcomes for patients undergoing total hip replacement?

    Rosendal, H.; Beekum, W.T. van; Nijhof, P.; Witte, L.P. de; Schrijvers, A.J.P.

    2000-01-01

    Objectives: To assess whether shared care for patients undergoing total hip replacement delivers better outcomes compared to care as usual. Design: Prospective, observational cohort study. Setting: Two regions in the Netherlands where different organisational health care models have been

  19. [A prophylactic program for strain urinary incontinence].

    Stadnicka, Grazyna; Iwanowicz-Palus, Grazyna J; Bień, Agnieszka M

    2002-01-01

    The aim of the study was to work out a prophylactic program for strain urinary incontinence. Analysis of literature on the subject and results of own investigations presented in the first part of the paper indicate that the program of prophylaxis of strain urinary incontinence should primarily include: (1) Preparation of the medical staff (nurses, midwives) for propagating health education among women on prevention of strain urinary incontinence. (2) Preparation of adequate educational materials in the form of brochures, leaflets, information posters about symptoms, causes and prophylaxis of urinary incontinence indicating health care institutions available to all women when the disease is suspected or already present. (3) Propagation of problems connected with strain urinary incontinence in the mass media providing information to a wide audience in order to make people realize the significance of this social problem and break stereotypes associated with this disease of "shame". (4) Preparation of sets of exercises for the muscles of the base of the pelvis to be performed during pregnancy, confinement and menopause to maintain their proper function. (5) Indicating factors predisposing to strain urinary incontinence with focus on possibilities of their reduction or elimination.

  20. Probiotic features of Lactobacillus plantarum mutant strains.

    Bove, Pasquale; Gallone, Anna; Russo, Pasquale; Capozzi, Vittorio; Albenzio, Marzia; Spano, Giuseppe; Fiocco, Daniela

    2012-10-01

    In this study, the probiotic potential of Lactobacillus plantarum wild-type and derivative mutant strains was investigated. Bacterial survival was evaluated in an in vitro system, simulating the transit along the human oro-gastro-intestinal tract. Interaction with human gut epithelial cells was studied by assessing bacterial adhesive ability to Caco-2 cells and induction of genes involved in innate immunity. L. plantarum strains were resistant to the combined stress at the various steps of the simulated gastrointestinal tract. Major decreases in the viability of L. plantarum cells were observed mainly under drastic acidic conditions (pH ≤ 2.0) of the gastric compartment. Abiotic stresses associated to small intestine poorly affected bacterial viability. All the bacterial strains significantly adhered to Caco-2 cells, with the ΔctsR mutant strain exhibiting the highest adhesion. Induction of immune-related genes resulted higher upon incubation with heat-inactivated bacteria rather than with live ones. For specific genes, a differential transcriptional pattern was observed upon stimulation with different L. plantarum strains, evidencing a possible role of the knocked out bacterial genes in the modulation of host cell response. In particular, cells from Δhsp18.55 and ΔftsH mutants strongly triggered immune defence genes. Our study highlights the relevance of microbial genetic background in host-probiotic interaction and might contribute to identify candidate bacterial genes and molecules involved in probiosis.

  1. Brittle superconducting magnets: an equivilent strain model

    Barzi, E.; Danuso, M.

    2010-01-01

    To exceed fields of 10 T in accelerator magnets, brittle superconductors like A15 Nb 3 Sn and Nb 3 Al or ceramic High Temperature Superconductors have to be used. For such brittle superconductors it is not their maximum tensile yield stress that limits their structural resistance as much as strain values that provoke deformations in their delicate lattice, which in turn affect their superconducting properties. Work on the sensitivity of Nb 3 Sn cables to strain has been conducted in a number of stress states, including uniaxial and multi-axial, producing usually different results. This has made the need of a constituent design criterion imperative for magnet builders. In conventional structural problems an equivalent stress model is typically used to verify mechanical soundness. In the superconducting community a simple scalar equivalent strain to be used in place of an equivalent stress would be an extremely useful tool. As is well known in fundamental mechanics, there is not one single way to reduce a multiaxial strain state as represented by a 2nd order tensor to a scalar. The conceptual experiment proposed here will help determine the best scalar representation to use in the identification of an equivalent strain model.

  2. Novel distributed strain sensing in polymeric materials

    Abot, Jandro L; Song, Yi; Medikonda, Sandeep; Rooy, Nathan; Schulz, Mark J

    2010-01-01

    Monitoring the state of strain throughout an entire structure is essential to determine its state of stress, detect potential residual stresses after fabrication, and also to help to establish its integrity. Several sensing technologies are presently available to determine the strain in the surface or inside a structure. Large sensor dimensions, complex signal conditioning equipment, and difficulty in achieving a widely distributed system have however hindered their development into robust structural health monitoring techniques. Recently, carbon nanotube forests were spun into a microscale thread that is electrically conductive, tough, and easily tailorable. The thread was integrated into polymeric materials and used for the first time as a piezoresistive sensor to monitor strain and also to detect damage in the material. It is revealed that the created self-sensing polymeric materials are sensitive to normal strains above 0.07% and that the sensor thread exhibits a perfectly linear delta resistance–strain response above 0.3%. The longitudinal gauge factors were determined to be in the 2–5 range. This low cost and simple built-in sensor thread may provide a new integrated and distributed sensor technology that enables robust real-time health monitoring of structures

  3. Crack initiation under generalized plane strain conditions

    Shum, D.K.M.; Merkle, J.G.

    1991-01-01

    A method for estimating the decrease in crack-initiation toughness, from a reference plane strain value, due to positive straining along the crack front of a circumferential flaw in a reactor pressure vessel is presented in this study. This method relates crack initiation under generalized plane strain conditions with material failure at points within a distance of a few crack-tip-opening displacements ahead of a crack front, and involves the formulation of a micromechanical crack-initiation model. While this study is intended to address concerns regarding the effects of positive out-of- plane straining on ductile crack initiation, the approach adopted in this work can be extended in a straightforward fashion to examine conditions of macroscopic cleavage crack initiation. Provided single- parameter dominance of near-tip fields exists in the flawed structure, results from this study could be used to examine the appropriateness of applying plane strain fracture toughness to the evaluation of circumferential flaws, in particular to those in ring-forged vessels which have no longitudinal welds. In addition, results from this study could also be applied toward the analysis of the effects of thermal streaming on the fracture resistance of circumferentially oriented flaws in a pressure vessel. 37 refs., 8 figs., 1 tab

  4. On the prediction of ductile fracture by void coalescence and strain localization

    Luo, Tuo; Gao, Xiaosheng

    2018-04-01

    This paper presents a unit cell model based on the observation that ductile fracture occurs when plastic flow is localized in a band. The unit cell consists of three void containing material units stacked in the direction normal to the localization plane. Localization takes place in the middle material unit while the two outer units undergo elastic recovery after failure occurs. Thus a failure criterion is established as when the macroscopic effective strain of the outer material units reaches the maximum value. Analyses are conducted to demonstrate the effect of the voids existing outside the localization band. Comparisons of the present model with several previous models suggest that the present model is not only easy to implement in finite element analysis but also more suitable to robustly determine the failure strain. A series of unit cell analyses are conducted for various macroscopic stress triaxialities and Lode parameters. The analysis results confirm that for a fixed Lode parameter, the failure strain decreases exponentially with the stress triaxiality and for a given stress triaxiality, it increases as the stress state approaches the generalized tension and generalized compression. The analysis results also reveal the effect of the stress state on the deformed void shape within and near the localization band.

  5. Activation of Multiple Antibiotic Resistance in Uropathogenic Escherichia coli Strains by Aryloxoalcanoic Acid Compounds

    Balagué, Claudia; Véscovi, Eleonora García

    2001-01-01

    Clofibric and ethacrynic acids are prototypical pharmacological agents administered in the treatment of hypertrigliceridemia and as a diuretic agent, respectively. They share with 2,4-dichlorophenoxyacetic acid (the widely used herbicide known as 2,4-D) a chlorinated phenoxy structural moiety. These aryloxoalcanoic agents (AOAs) are mainly excreted by the renal route as unaltered or conjugated active compounds. The relatedness of these agents at the structural level and their potential effect on therapeutically treated or occupationally exposed individuals who are simultaneously undergoing a bacterial urinary tract infection led us to analyze their action on uropathogenic, clinically isolated Escherichia coli strains. We found that exposure to these compounds increases the bacterial resistance to an ample variety of antibiotics in clinical isolates of both uropathogenic and nonpathogenic E. coli strains. We demonstrate that the AOAs induce an alteration of the bacterial outer membrane permeability properties by the repression of the major porin OmpF in a micF-dependent process. Furthermore, we establish that the antibiotic resistance phenotype is primarily due to the induction of the MarRAB regulatory system by the AOAs, while other regulatory pathways that also converge into micF modulation (OmpR/EnvZ, SoxRS, and Lrp) remained unaltered. The fact that AOAs give rise to uropathogenic strains with a diminished susceptibility to antimicrobials highlights the impact of frequently underestimated or ignored collateral effects of chemical agents. PMID:11353631

  6. Impact of smoking on early clinical outcomes in patients undergoing coronary artery bypass grafting surgery

    Ji, Qiang; Zhao, Hang; Mei, YunQing; Shi, YunQing; Ma, RunHua; Ding, WenJun

    2015-01-01

    Background To evaluate the impact of persistent smoking versus smoking cessation over one month prior to surgery on early clinical outcomes in Chinese patients undergoing isolated coronary artery bypass grafting (CABG) surgery in a retrospective study. Methods The peri-operative data of consecutive well-documented patients undergoing isolated CABG surgery from January 2007 to December 2013 were investigated and retrospectively analyzed. All included patients were divided into either a non-smo...

  7. Anaesthesia in patients undergoing esophago-gastro-duodenoscopy for suspected bleeding

    Helsø, Ida; Risom, Martin; Vestergaard, Therese Risom

    2017-01-01

    INTRODUCTION: Upper gastrointestinal bleeding (UGIB) is a common emergency. Currently, there are no agreed guidelines on the level of anaesthetic support required in patients undergoing acute esophago-gastro-duodendoscopy (EGD). METHODS: An online questionnaire comprising 19 questions was distrib......INTRODUCTION: Upper gastrointestinal bleeding (UGIB) is a common emergency. Currently, there are no agreed guidelines on the level of anaesthetic support required in patients undergoing acute esophago-gastro-duodendoscopy (EGD). METHODS: An online questionnaire comprising 19 questions...

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

    Tengberg, L. T.; Bay-Nielsen, M.; Bisgaard, T.

    2017-01-01

    Background: Acute high-risk abdominal (AHA) surgery carries a very high risk of morbidity and mortality and represents a massive healthcare burden. The aim of the present study was to evaluate the effect of a standardized multidisciplinary perioperative protocol in patients undergoing AHA surgery...... = 0·004). Conclusion: The introduction of a multidisciplinary perioperative protocol was associated with a significant reduction in postoperative mortality in patients undergoing AHA surgery. NCT01899885 (http://www.clinicaltrials.gov)....

  9. Measuring pain in patients undergoing hemodialysis: a review of pain assessment tools

    Upadhyay, Chandani; Cameron, Karen; Murphy, Laura; Battistella, Marisa

    2014-01-01

    Background Patients undergoing hemodialysis frequently report pain with multifactorial causes, not limited to that experienced directly from hemodialysis treatment. Their pain may be nociceptive, neuropathic, somatic or visceral in nature. Despite this, pain in this population remains under-recognized and under-treated. Although several tools have been used to measure pain in patients undergoing hemodialysis as reported in the literature, none of them have been validated specifically in this ...

  10. Psychological Symptoms among Workers Employed in Companies Undergoing Privatization in Postwar Bosnia and Herzegovina

    Avdibegović, Esmina; Hasanović, Mevludin; Hodžić, Medin; Selimbašić, Zihnet

    2011-01-01

    In Central and Eastern European countries, after abandoning communism, significant political, economic and social changes occurred, followed by the increase in income inequality and social disparity. The goal of this study was to examine the relationship between psychological symptoms and monthly income of employees in companies undergoing privatization. The study included 258 workers from seven companies undergoing privatization in the Tuzla Canton region. For the study purposes,...

  11. Mycoplasma in urine and blood following catheterisation of patients undergoing vascular surgery

    Levi, N; Eiberg, J; Skov Jensen, J

    1997-01-01

    The purpose of this investigation was to determine if mycoplasmas enter the bloodstream after urinary tract catheterisation in patients undergoing vascular surgery in order to evaluate the efficiency of the routine prophylactic antibiotic treatment.......The purpose of this investigation was to determine if mycoplasmas enter the bloodstream after urinary tract catheterisation in patients undergoing vascular surgery in order to evaluate the efficiency of the routine prophylactic antibiotic treatment....

  12. Evaluation of the Escherichia coli (E.coli Strains based on protein profiles obtained from traditional Ice cream in Isfahan City

    Maryam Ranjbar

    2016-06-01

    Full Text Available Introduction: Bacterial strains present in food products undergo different thermal processes such as coldness and warmth. Such cases cause a shock in bacteria and force the bacteria to produce proteins and partly, develop a change in the production of enzyme. This can give the strain a special characteristic, knowledge of this characteristic will contribute to a timely and more precise identification. Materials and methods: During this time more than 100 samples have been examined, out of which, 48 Indol positive isolation samples were examined by phenotypic tests and sodium dodecyle sulphate polyacrylamide gel electrophoresis (SDS- PAGE. Results: – The results of numerical analysis of phenotypic characteristics and protein patterns showed that only 79% of the collected isolates (phenon 1 and 2 could be identified as E.coli compared with reference strains. E.coli strains from ice creams were showed some Variation in banding patterns. Major differences were observed in protein bands between 23.59 - and 20.79 -kDa molecular mass range which the isolates were compared with reference strains. Discussion and conclusion: Our study concluded that food’s bacterial strains are influenced by temperatures in different processes and also it could stimulate the production of proteins or change the enzymes. Therefore, The reason of taking care of the issues is that changes in the proteins’ structures can lead to change in the biochemical properties, and finally this change can misguide us. Further research is being performed to characterize these atypical strains by molecular methods.

  13. Methodology to measure strains at high temperatures using electrical strain gages with free filaments

    Atanazio Filho, Nelson N.; Gomes, Paulo T. Vida; Scaldaferri, Denis H.B.; Silva, Luiz L. da; Rabello, Emerson G.; Mansur, Tanius R.

    2013-01-01

    An experimental methodology used for strains measuring at high temperatures is show in this work. In order to do the measurements, it was used electric strain gages with loose filaments attached to a stainless steel 304 beam with specific cements. The beam has triangular shape and a constant thickness, so the strain is the same along its length. Unless the beam surface be carefully prepared, the strain gage attachment is not efficient. The showed results are for temperatures ranging from 20 deg C to 300 deg C, but the experimental methodology could be used to measure strains at a temperature up to 900 deg C. Analytical calculations based on solid mechanics were used to verify the strain gage electrical installation and the measured strains. At a first moment, beam deformations as a temperature function were plotted. After that, beam deformations with different weighs were plotted as a temperature function. The results shown allowed concluding that the experimental methodology is trustable to measure strains at temperatures up to 300 deg C. (author)

  14. Thermal strain measurement of EAST W/Cu divertor structure using electric resistance strain gauges

    Wang, Xingli [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, 230031 (China); Science Island Branch of Graduate School, University of Science & Technology of China, Hefei, 230031 (China); Wang, Wanjing, E-mail: wjwang@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, 230031 (China); Wang, Jichao [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, 230031 (China); Wei, Ran; Sun, Zhaoxuan [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, 230031 (China); Science Island Branch of Graduate School, University of Science & Technology of China, Hefei, 230031 (China); Li, Qiang; Xie, Chunyi [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, 230031 (China); Chen, Hong-En; Wang, Kaiqiang; Wu, Lei; Chen, Zhenmao [State Key Lab for Strength and Vibration of Mechanical Structures, Xi’an Jiaotong University (China); Luo, Guang-Nan [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, 230031 (China); Science Island Branch of Graduate School, University of Science & Technology of China, Hefei, 230031 (China); Hefei Center for Physical Science and Technology, Hefei, 230022 (China); Hefei Science Center of Chinese Academy of Sciences, Hefei, 230027 (China)

    2016-12-15

    Highlights: • To understand the service behavior of W/Cu divertor, an electrical resistance strain gauge system had been introduced in a thermal strain measurement experiment. • The measurement system successfully finished the experiment and obtained valued thermal strain data. • Two thermomechanical analyses had also been carried out and compared with the measurement results. • Experiment results corresponded well to simulations and threw a light upon the failure of W/Cu divertor in the previous baking tests. - Abstract: W/Cu divertor has complex structure and faces extreme work environment in EAST Tokamak device. To measure its thermal strain shall be a valued way to understand its service behavior and then optimize its design and manufacturing process. This work presents a preliminary study on measuring thermal strain of EAST W/Cu divertor structure using electric resistance strain gauges. Eight gauges had been used in the experiment and the heating temperature had been set to 230 °C with respect to the work temperature. To realize the measuring experiment, an appropriate fixing method of gauges in divertor narrow spaces had been taken and tested, which could not only withstand high temperature but also had no damage to the divertor sample. The measurement results were that three gauges showed positive strain while other three showed negative strain after having been compensated, which corresponded to tensile stress and compressed stress respectively. Two thermomechanical simulations had also been carried out and used for comparing with the experiment.

  15. Strain histograms are equal to strain ratios in predicting malignancy in breast tumours

    Carlsen, Jonathan Frederik; Ewertsen, Caroline; Sletting, Susanne

    2017-01-01

    Objectives: To assess whether strain histograms are equal to strain ratios in predicting breast tumour malignancy and to see if either could be used to upgrade Breast Imaging Reporting and Data System (BI-RADS) 3 tumours for immediate biopsy. Methods: Ninety-nine breast tumours were examined using...

  16. Validation of perceptual strain index to evaluate the thermal strain in experimental hot conditions

    Habibollah Dehghan

    2015-01-01

    Conclusions: The research findings showed when there is no access to other forms of methods to evaluate the heat stress, it can be used the PeSI in evaluating the strain because of its favorable correlation with the thermal strain.

  17. Mechanical properties of biaxially strained poly(L-lactide) tubes: Strain rate and temperature dependence

    Løvdal, Alexandra Liv Vest; Andreasen, Jens Wenzel; Mikkelsen, Lars Pilgaard

    2017-01-01

    Poly(l-lactide) (PLLA) is a bioabsorbable polymer with high stiffness and strength compared to the other commercially available bioabsorbable polymers. The properties of PLLA can be improved by straining, causing deformation-mediated molecular orientation. PLLA tubes were biaxially strained above...

  18. Hypovitaminosis D in patients undergoing kidney transplant: the importance of sunlight exposure

    Cristiane F. Vilarta

    Full Text Available OBJECTIVES: Recent studies have shown a high prevalence of hypovitaminosis D, defined as a serum 25-hydroxyvitamin D level less than 30 ng/ml, in both healthy populations and patients with chronic kidney disease. Patients undergoing kidney transplant are at an increased risk of skin cancer and are advised to avoid sunlight exposure. Therefore, these patients might share two major risk factors for hypovitaminosis D: chronic kidney disease and low sunlight exposure. This paper describes the prevalence and clinical characteristics of hypovitaminosis D among patients undergoing kidney transplant. METHODS: We evaluated 25-hydroxyvitamin D serum levels in a representative sample of patients undergoing kidney transplant. We sought to determine the prevalence of hypovitaminosis D, compare these patients with a control group, and identify factors associated with hypovitaminosis D (e.g., sunlight exposure and dietary habits. RESULTS: Hypovitaminosis D was found in 79% of patients undergoing kidney transplant, and the major associated factor was low sunlight exposure. These patients had higher creatinine and intact parathyroid hormone serum levels, with 25-hydroxyvitamin D being inversely correlated with intact parathyroid hormone serum levels. Compared with the control group, patients undergoing kidney transplant presented a higher prevalence of 25-hydroxyvitamin D deficiency and lower serum calcium, phosphate and albumin but higher creatinine and intact parathyroid hormone levels. CONCLUSIONS: Our results confirmed the high prevalence of hypovitaminosis D in patients undergoing kidney transplant. Therapeutic strategies such as moderate sunlight exposure and vitamin D supplementation should be seriously considered for this population.

  19. Residual strains in girth-welded linepipe

    MacEwen, S.R.; Holden, T.M.; Powell, B.M.; Lazor, R.B.

    1987-07-01

    High resolution neutron diffraction has been used to measure the axial residual strains in and adjacent to a multipass girth weld in a complete section of 914 mm (36 inches) diameter, 16 mm (5/8 inch) wall, linepipe. The experiments were carried out at the NRU reactor, Chalk River using the L3 triple-axis spectrometer. The through-wall distribution of axial residual strain was measured at 0, 4, 8, 20 and 50 mm from the weld centerline; the axial variation was determined 1, 5, 8, and 13 mm from the inside surface of the pipe wall. The results have been compared with strain gauge measurements on the weld surface and with through-wall residual stress distributions determined using the block-layering and removal technique

  20. High Strain Rate Characterisation of Composite Materials

    Eriksen, Rasmus Normann Wilken

    -reinforced polymers, were considered, and it was first shown that the loading history controls equilibrium process. Then the High-speed servo-hydraulic test machine was analysed in terms its ability to create a state of constant strain rate in the specimen. The invertible inertial forces in the load train prevented...... from designing and constructing a high-speed servo-hydraulic test machine and by performing a comprehensive test series. The difficulties encountered in the test work could be addressed with the developed analysis. The conclusion was that the High-speed servo-hydraulic test machine is less suited...... for testing fibre-reinforced polymers due to their elastic behaviour and low strain to failure. This is problematic as the High-speed servo-hydraulic test machine closes the gap between quasi-static tests rates and lower strain rates, which are achievable with the Split Hopkinson Pressure Bar. The Split...

  1. Developments of borehole strain observation outside China

    邱泽华; 石耀霖

    2004-01-01

    Borehole strain observation is playing an increasingly important role in the study on the crustal movements. It hasbeen used by many countries such as China, USA, Japan, Peru, Australia, South Africa, Iceland and Italy, in research fields of plate tectonics, earthquake, volcanic eruption, dam safety, oil field subsidence, mining collapse andso on. Borehole strainmeter has been improved rapidly and tends to get more and more components included inone probe. Based on observations by this kind of instruments, studies on seismic strain step, slow earthquake,earthquake precursor and volcanic eruption forecasting have made remarkable achievements. In the coming years,borehole strain observation is going to become one major geodetic means, together with GPS and InSAR.

  2. The asymptomatic bacteriuria Escherichia coli strain 83972 outcompetes uropathogenic E. coli strains in human urine

    Hancock, Viktoria; Ulett, G.C.; Schembri, M.A.

    2006-01-01

    Escherichia coli is the most common organism associated with asymptomatic bacteriuria (ABU). In contrast to uropathogenic E. coli (UPEC), which causes symptomatic urinary tract infections (UTI), very little is known about the mechanisms by which these strains colonize the human urinary tract....... The prototype ABU E. coli strain 83972 was originally isolated from a girl who had carried it asymptomatically for 3 years. Deliberate colonization of UTI-susceptible individuals with E. coli 83972 has been used successfully as an alternative approach for the treatment of patients who are refractory...... to conventional therapy. Colonization with strain 83972 appears to prevent infection with UPEC strains in such patients despite the fact that this strain is unable to express the primary adhesins involved in UTI, viz. P and type 1 fimbriae. Here we investigated the growth characteristics of E. coli 83972 in human...

  3. Evaluating location specific strain rates, temperatures, and accumulated strains in friction welds through microstructure modeling

    Javed Akram

    2018-04-01

    Full Text Available A microstructural simulation method is adopted to predict the location specific strain rates, temperatures, grain evolution, and accumulated strains in the Inconel 718 friction welds. Cellular automata based 2D microstructure model was developed for Inconel 718 alloy using theoretical aspects of dynamic recrystallization. Flow curves were simulated and compared with experimental results using hot deformation parameter obtained from literature work. Using validated model, simulations were performed for friction welds of Inconel 718 alloy generated at three rotational speed i.e., 1200, 1500, and 1500 RPM. Results showed the increase in strain rates with increasing rotational speed. These simulated strain rates were found to match with the analytical results. Temperature difference of 150 K was noticed from center to edge of the weld. At all the rotational speeds, the temperature was identical implying steady state temperature (0.89Tm attainment. Keywords: Microstructure modeling, Dynamic recrystallization, Friction welding, Inconel 718, EBSD, Hot deformation, Strain map

  4. A new strain gage method for measuring the contractile strain ratio of Zircaloy tubing

    Hwang, S.K.; Sabol, G.P.

    1988-01-01

    An improved strain gage method for determining the contractile strain ratio (CSR) of Zircaloy tubing was developed. The new method consists of a number of load-unload cyclings at approximately 0.2% plastic strain interval. With this method the CSR of Zircaloy-4 tubing could be determined accurately because it was possible to separate the plastic strains from the elastic strain involvement. The CSR values determined by use of the new method were in good agreement with those calculated from conventional post-test manual measurements. The CSR of the tubing was found to decrease with the amount of deformation during testing because of uneven plastic flow in the gage section. A new technique of inscribing gage marks by use of a YAG laser is discussed. (orig.)

  5. Segregation of genes from donor strain during the production of recombinant congenic strains.

    van Zutphen, L F; Den Bieman, M; Lankhorst, A; Demant, P

    1991-07-01

    Recombinant congenic strains (RCS) constitute a set of inbred strains which are designed to dissect the genetic control of multigenic traits, such as tumour susceptibility or disease resistance. Each RCS contains a small fraction of the genome of a common donor strain, while the majority of genes stem from a common background strain. We tested at two stages of the inbreeding process in 20 RCS, derived from BALB/cHeA and STS/A, to see whether alleles from the STS/A donor strain are distributed over the RCS in a ratio as would theoretically be expected. Four marker genes (Pep-3; Pgm-1; Gpi-1 and Es-3) located at 4 different chromosomes were selected and the allelic distribution was tested after 3-4 and after 12 generations of inbreeding. The data obtained do not significantly deviate from the expected pattern, thus supporting the validity of the concept of RCS.

  6. Pheromonal divergence between two strains of Spodoptera frugiperda

    Unbehend, M.; Hänniger, S.; Meagher, R.L.; Heckel, D.G.; Groot, A.T.

    2013-01-01

    Spodoptera frugiperda consists of two genetically and behaviorally different strains, the corn- and the rice-strain, which seem to be in the process of sympatric speciation. We investigated the role of strain-specific sexual communication as a prezygotic mating barrier between both strains by

  7. Comparative developmental trajectory of four strains of chicken ...

    This study evaluated egg traits, embryonic growth, and early growth rate in four strains of chicken. A total of 1200 hatching eggs, 300 each from four strains of chicken were used for this study. The strains included Nigerian indigenous chicken (NIC), Arbor acre, Hubbard, and Marshall broiler strains. Embryonic weights, yolk ...

  8. ANISOTROPIC STRAIN-HARDENING IN POLYCRYSTALLINE COPPER AND ALUMINUM

    HESS, F

    1993-01-01

    A new viscoplastic model for the plastic stress-strain behaviour of f.c.c. metals is presented. In this model the strain hardening results from increasing dislocation densities. The observed stagnation of strain hardening after strain reversals is explained by a lowering of the increase in

  9. Nucleation versus instability race in strained films

    Liu, Kailang; Berbezier, Isabelle; David, Thomas; Favre, Luc; Ronda, Antoine; Abbarchi, Marco; Voorhees, Peter; Aqua, Jean-Noël

    2017-10-01

    Under the generic term "Stranski-Krastanov" are grouped two different growth mechanisms of SiGe quantum dots. They result from the self-organized Asaro-Tiller-Grinfel'd (ATG) instability at low strain, while at high strain, from a stochastic nucleation. While these regimes are well known, we elucidate here the origin of the transition between these two pathways thanks to a joint theoretical and experimental work. Nucleation is described within the master equation framework. By comparing the time scales for ATG instability development and three-dimensional (3D) nucleation onset, we demonstrate that the transition between these two regimes is simply explained by the crossover between their divergent evolutions. Nucleation exhibits a strong exponential deviation at low strain while ATG behaves only algebraically. The associated time scale varies with exp(1 /x4) for nucleation, while it only behaves as 1 /x8 for the ATG instability. Consequently, at high (low) strain, nucleation (instability) occurs faster and inhibits the alternate evolution. It is then this different kinetic evolution which explains the transition from one regime to the other. Such a kinetic view of the transition between these two 3D growth regimes was not provided before. The crossover between nucleation and ATG instability is found to occur both experimentally and theoretically at a Ge composition around 50% in the experimental conditions used here. Varying the experimental conditions and/or the system parameters does not allow us to suppress the transition. This means that the SiGe quantum dots always grow via ATG instability at low strain and nucleation at high strain. This result is important for the self-organization of quantum dots.

  10. Tensile strain mapping in flat germanium membranes

    Rhead, S. D.; Halpin, J. E.; Myronov, M.; Patchett, D. H.; Allred, P. S.; Wilson, N. R.; Leadley, D. R.; Shah, V. A.; Kachkanov, V.; Dolbnya, I. P.; Reparaz, J. S.; Sotomayor Torres, C. M.

    2014-01-01

    Scanning X-ray micro-diffraction has been used as a non-destructive probe of the local crystalline quality of a thin suspended germanium (Ge) membrane. A series of reciprocal space maps were obtained with ∼4 μm spatial resolution, from which detailed information on the strain distribution, thickness, and crystalline tilt of the membrane was obtained. We are able to detect a systematic strain variation across the membranes, but show that this is negligible in the context of using the membranes as platforms for further growth. In addition, we show evidence that the interface and surface quality is improved by suspending the Ge

  11. Tensile strain mapping in flat germanium membranes

    Rhead, S. D., E-mail: S.Rhead@warwick.ac.uk; Halpin, J. E.; Myronov, M.; Patchett, D. H.; Allred, P. S.; Wilson, N. R.; Leadley, D. R. [Department of Physics, University of Warwick, Coventry, CV4 7AL (United Kingdom); Shah, V. A. [Department of Physics, University of Warwick, Coventry, CV4 7AL (United Kingdom); Department of Engineering, University of Warwick, Coventry, CV4 7AL (United Kingdom); Kachkanov, V.; Dolbnya, I. P. [Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE (United Kingdom); Reparaz, J. S. [ICN2 - Institut Catala de Nanociencia i Nanotecnologia, Campus UAB, 08193 Bellaterra (Barcelona) (Spain); Sotomayor Torres, C. M. [ICN2 - Institut Catala de Nanociencia i Nanotecnologia, Campus UAB, 08193 Bellaterra (Barcelona) (Spain)

    2014-04-28

    Scanning X-ray micro-diffraction has been used as a non-destructive probe of the local crystalline quality of a thin suspended germanium (Ge) membrane. A series of reciprocal space maps were obtained with ∼4 μm spatial resolution, from which detailed information on the strain distribution, thickness, and crystalline tilt of the membrane was obtained. We are able to detect a systematic strain variation across the membranes, but show that this is negligible in the context of using the membranes as platforms for further growth. In addition, we show evidence that the interface and surface quality is improved by suspending the Ge.

  12. Cells as strain-cued automata

    Cox, Brian N.; Snead, Malcolm L.

    2016-02-01

    We argue in favor of representing living cells as automata and review demonstrations that autonomous cells can form patterns by responding to local variations in the strain fields that arise from their individual or collective motions. An autonomous cell's response to strain stimuli is assumed to be effected by internally-generated, internally-powered forces, which generally move the cell in directions other than those implied by external energy gradients. Evidence of cells acting as strain-cued automata have been inferred from patterns observed in nature and from experiments conducted in vitro. Simulations that mimic particular cases of pattern forming share the idealization that cells are assumed to pass information among themselves solely via mechanical boundary conditions, i.e., the tractions and displacements present at their membranes. This assumption opens three mechanisms for pattern formation in large cell populations: wavelike behavior, kinematic feedback in cell motility that can lead to sliding and rotational patterns, and directed migration during invasions. Wavelike behavior among ameloblast cells during amelogenesis (the formation of dental enamel) has been inferred from enamel microstructure, while strain waves in populations of epithelial cells have been observed in vitro. One hypothesized kinematic feedback mechanism, "enhanced shear motility", accounts successfully for the spontaneous formation of layered patterns during amelogenesis in the mouse incisor. Directed migration is exemplified by a theory of invader cells that sense and respond to the strains they themselves create in the host population as they invade it: analysis shows that the strain fields contain positional information that could aid the formation of cell network structures, stabilizing the slender geometry of branches and helping govern the frequency of branch bifurcation and branch coalescence (the formation of closed networks). In simulations of pattern formation in

  13. Genotypic Diversity within a Single Pseudomonas aeruginosa Strain Commonly Shared by Australian Patients with Cystic Fibrosis.

    Anna Sze Tai

    Full Text Available In cystic fibrosis (CF, Pseudomonas aeruginosa undergoes intra-strain genotypic and phenotypic diversification while establishing and maintaining chronic lung infections. As the clinical significance of these changes is uncertain, we investigated intra-strain diversity in commonly shared strains from CF patients to determine if specific gene mutations were associated with increased antibiotic resistance and worse clinical outcomes. Two-hundred-and-one P. aeruginosa isolates (163 represented a dominant Australian shared strain, AUST-02 from two Queensland CF centres over two distinct time-periods (2001-2002 and 2007-2009 underwent mexZ and lasR sequencing. Broth microdilution antibiotic susceptibility testing in a subset of isolates was also performed. We identified a novel AUST-02 subtype (M3L7 in adults attending a single Queensland CF centre. This M3L7 subtype was multi-drug resistant and had significantly higher antibiotic minimum inhibitory concentrations than other AUST-02 subtypes. Prospective molecular surveillance using polymerase chain reaction assays determined the prevalence of the 'M3L7' subtype at this centre during 2007-2009 (170 patients and 2011 (173 patients. Three-year clinical outcomes of patients harbouring different strains and subtypes were compared. MexZ and LasR sequences from AUST-02 isolates were more likely in 2007-2009 than 2001-2002 to exhibit mutations (mexZ: odds ratio (OR = 3.8; 95% confidence interval (CI: 1.1-13.5 and LasR: OR = 2.5; 95%CI: 1.3-5.0. Surveillance at the adult centre in 2007-2009 identified M3L7 in 28/509 (5.5% P. aeruginosa isolates from 13/170 (7.6% patients. A repeat survey in 2011 identified M3L7 in 21/519 (4.0% P. aeruginosa isolates from 11/173 (6.4% patients. The M3L7 subtype was associated with greater intravenous antibiotic and hospitalisation requirements, and a higher 3-year risk of death/lung transplantation, than other AUST-02 subtypes (adjusted hazard ratio [HR] = 9.4; 95%CI: 2

  14. X-ray diffraction study of elastic strains for modelling γ/γ' two-phase behavior

    Durand, L.; Massaoudi, M.; Lavelle, B.

    2005-01-01

    To describe the two-phase monocrystals behavior, we used has X-rays diffraction method. Our study is based on the mechanics of the continuous media framework in elasticity. We extend to the quadratic structure the study by X-rays developed at the laboratory on cubic materials with coarse grains. We show that the two phases γ and γ' undergo a tetragonal distortion and that the strains are not constant in each phase. Our results are in agreement with a study by the finite element method developed in addition

  15. Haemophilus ducreyi Cutaneous Ulcer Strains Diverged from Both Class I and Class II Genital Ulcer Strains: Implications for Epidemiological Studies.

    Dharanesh Gangaiah

    2016-12-01

    Full Text Available Haemophilus ducreyi has emerged as a major cause of cutaneous ulcers (CU in yaws-endemic regions of the tropics in the South Pacific, South East Asia and Africa. H. ducreyi was once thought only to cause the genital ulcer (GU disease chancroid; GU strains belong to 2 distinct classes, class I and class II. Using whole-genome sequencing of 4 CU strains from Samoa, 1 from Vanuatu and 1 from Papua New Guinea, we showed that CU strains diverged from the class I strain 35000HP and that one CU strain expressed β-lactamase. Recently, the Center for Disease Control and Prevention released the genomes of 11 additional CU strains from Vanuatu and Ghana; however, the evolutionary relationship of these CU strains to previously-characterized CU and GU strains is unknown.We performed phylogenetic analysis of 17 CU and 10 GU strains. Class I and class II GU strains formed two distinct clades. The class I strains formed two subclades, one containing 35000HP and HD183 and the other containing the remainder of the class I strains. Twelve of the CU strains formed a subclone under the class I 35000HP subclade, while 2 CU strains formed a subclone under the other class I subclade. Unexpectedly, 3 of the CU strains formed a subclone under the class II clade. Phylogenetic analysis of dsrA-hgbA-ncaA sequences yielded a tree similar to that of whole-genome phylogenetic tree.CU strains diverged from multiple lineages within both class I and class II GU strains. Multilocus sequence typing of dsrA-hgbA-ncaA could be reliably used for epidemiological investigation of CU and GU strains. As class II strains grow relatively poorly and are relatively more susceptible to vancomycin than class I strains, these findings have implications for methods to recover CU strains. Comparison of contemporary CU and GU isolates would help clarify the relationship between these entities.

  16. Haemophilus ducreyi Cutaneous Ulcer Strains Diverged from Both Class I and Class II Genital Ulcer Strains: Implications for Epidemiological Studies.

    Gangaiah, Dharanesh; Spinola, Stanley M

    2016-12-01

    Haemophilus ducreyi has emerged as a major cause of cutaneous ulcers (CU) in yaws-endemic regions of the tropics in the South Pacific, South East Asia and Africa. H. ducreyi was once thought only to cause the genital ulcer (GU) disease chancroid; GU strains belong to 2 distinct classes, class I and class II. Using whole-genome sequencing of 4 CU strains from Samoa, 1 from Vanuatu and 1 from Papua New Guinea, we showed that CU strains diverged from the class I strain 35000HP and that one CU strain expressed β-lactamase. Recently, the Center for Disease Control and Prevention released the genomes of 11 additional CU strains from Vanuatu and Ghana; however, the evolutionary relationship of these CU strains to previously-characterized CU and GU strains is unknown. We performed phylogenetic analysis of 17 CU and 10 GU strains. Class I and class II GU strains formed two distinct clades. The class I strains formed two subclades, one containing 35000HP and HD183 and the other containing the remainder of the class I strains. Twelve of the CU strains formed a subclone under the class I 35000HP subclade, while 2 CU strains formed a subclone under the other class I subclade. Unexpectedly, 3 of the CU strains formed a subclone under the class II clade. Phylogenetic analysis of dsrA-hgbA-ncaA sequences yielded a tree similar to that of whole-genome phylogenetic tree. CU strains diverged from multiple lineages within both class I and class II GU strains. Multilocus sequence typing of dsrA-hgbA-ncaA could be reliably used for epidemiological investigation of CU and GU strains. As class II strains grow relatively poorly and are relatively more susceptible to vancomycin than class I strains, these findings have implications for methods to recover CU strains. Comparison of contemporary CU and GU isolates would help clarify the relationship between these entities.

  17. Transesophageal echocardiographic strain imaging predicts aortic biomechanics: Beyond diameter.

    Emmott, Alexander; Alzahrani, Haitham; Alreishidan, Mohammed; Therrien, Judith; Leask, Richard L; Lachapelle, Kevin

    2018-03-11

    Clinical guidelines recommend resection of ascending aortic aneurysms at diameters 5.5 cm or greater to prevent rupture or dissection. However, approximately 40% of all ascending aortic dissections occur below this threshold. We propose new transesophageal echocardiography strain-imaging moduli coupled with blood pressure measurements to predict aortic dysfunction below the surgical threshold. A total of 21 patients undergoing aortic resection were recruited to participate in this study. Transesophageal echocardiography imaging of the aortic short-axis and invasive radial blood pressure traces were taken for 3 cardiac cycles. By using EchoPAC (GE Healthcare, Madison, Wis) and postprocessing in MATLAB (MathWorks, Natick, Mass), circumferential stretch profiles were generated and combined with the blood pressure traces. From these data, 2 in vivo stiffness moduli were calculated: the Cardiac Cycle Pressure Modulus and Cardiac Cycle Stress Modulus. From the resected aortic ring, testing squares were isolated for ex vivo mechanical analysis and histopathology. Each square underwent equibiaxial tensile testing to generate stress-stretch profiles for each patient. Two ex vivo indices were calculated from these profiles (energy loss and incremental stiffness) for comparison with the Cardiac Cycle Pressure Modulus and Cardiac Cycle Stress Modulus. The echo-derived stiffness moduli demonstrate positive significant covariance with ex vivo tensile biomechanical indices: energy loss (vs Cardiac Cycle Pressure Modulus: R 2  = 0.5873, P biomechanics and histopathology, which demonstrates the added benefit of using simple echocardiography-derived biomechanics to stratify patient populations. Copyright © 2018. Published by Elsevier Inc.

  18. Failure strains and proposed limit strains for an reactor pressure vessel under severe accident conditions

    Krieg, R.

    2005-01-01

    The local failure strains of essential design elements of a reactor vessel are investigated. The size influence of the structure is of special interest. Typical severe accident conditions including elevated temperatures and dynamic loads are considered. The main part of work consists of test families with specimens under uniaxial and biaxial load. Within one test family the specimen geometry and the load conditions are similar, but the size is varied up to reactor dimensions. Special attention is given to geometries with a hole or a notch causing non-uniform stress and strain distributions typical for the reactor vessel. A key problem is to determine the local failure strain. Here suitable methods had to be developed including the so-called 'vanishing gap method', and the 'forging die method'. They are based on post-test geometrical measurements of the fracture surfaces and reconstructions of the related strain fields using finite element models. The results indicate that stresses versus dimensionless deformations are approximately size independent up to failure for specimens of similar geometry under similar load conditions. Local failure strains could be determined. The values are rather high and size dependent. Statistical evaluation allow the proposal of limit strains which are also size dependent. If these limit strains are not exceeded, the structures will not fracture

  19. Mechanical strength model for plastic bonded granular materials at high strain rates and large strains

    Browning, R.V.; Scammon, R.J.

    1998-01-01

    Modeling impact events on systems containing plastic bonded explosive materials requires accurate models for stress evolution at high strain rates out to large strains. For example, in the Steven test geometry reactions occur after strains of 0.5 or more are reached for PBX-9501. The morphology of this class of materials and properties of the constituents are briefly described. We then review the viscoelastic behavior observed at small strains for this class of material, and evaluate large strain models used for granular materials such as cap models. Dilatation under shearing deformations of the PBX is experimentally observed and is one of the key features modeled in cap style plasticity theories, together with bulk plastic flow at high pressures. We propose a model that combines viscoelastic behavior at small strains but adds intergranular stresses at larger strains. A procedure using numerical simulations and comparisons with results from flyer plate tests and low rate uniaxial stress tests is used to develop a rough set of constants for PBX-9501. Comparisons with the high rate flyer plate tests demonstrate that the observed characteristic behavior is captured by this viscoelastic based model. copyright 1998 American Institute of Physics

  20. Life Stress, Strain, and Deviance Across Schools: Testing the Contextual Version of General Strain Theory in China.

    Zhang, Jinwu; Liu, Jianhong; Wang, Xin; Zou, Anquan

    2017-08-01

    General Strain Theory delineates different types of strain and intervening processes from strain to deviance and crime. In addition to explaining individual strain-crime relationship, a contextualized version of general strain theory, which is called the Macro General Strain Theory, has been used to analyze how aggregate variables influence aggregate and individual deviance and crime. Using a sample of 1,852 students (Level 1) nested in 52 schools (Level 2), the current study tests the Macro General Strain Theory using Chinese data. The results revealed that aggregate life stress and strain have influences on aggregate and individual deviance, and reinforce the individual stress-deviance association. The current study contributes by providing the first Macro General Strain Theory test based on Chinese data and offering empirical evidence for the multilevel intervening processes from strain to deviance. Limitations and future research directions are discussed.

  1. High strain rate behaviour of polypropylene microfoams

    Martínez A.B.

    2012-08-01

    Full Text Available Microcellular materials such as polypropylene foams are often used in protective applications and passive safety for packaging (electronic components, aeronautical structures, food, etc. or personal safety (helmets, knee-pads, etc.. In such applications the foams which are used are often designed to absorb the maximum energy and are generally subjected to severe loadings involving high strain rates. The manufacture process to obtain polymeric microcellular foams is based on the polymer saturation with a supercritical gas, at high temperature and pressure. This method presents several advantages over the conventional injection moulding techniques which make it industrially feasible. However, the effect of processing conditions such as blowing agent, concentration and microfoaming time and/or temperature on the microstructure of the resulting microcellular polymer (density, cell size and geometry is not yet set up. The compressive mechanical behaviour of several microcellular polypropylene foams has been investigated over a wide range of strain rates (0.001 to 3000 s−1 in order to show the effects of the processing parameters and strain rate on the mechanical properties. High strain rate tests were performed using a Split Hopkinson Pressure Bar apparatus (SHPB. Polypropylene and polyethylene-ethylene block copolymer foams of various densities were considered.

  2. Nature of interstitially induced lattice strains

    Emin, D.

    1978-01-01

    The addition of interstitial atoms to a metal lattice has been likened to the addition of extra billiard balls to an array of tangentially touching billiard balls. In such a picture the increased clustering of interstitials can lead to the buildup of larger and larger strain fields which ultimately are associated with the production of broken bonds. Simple models of the strain fields associated with the addition of particles to a lattice in which the force exerted between the added atoms and host atoms is finite have been studied. From these studies one can define situations in which the billiard-ball approach has qualitative validity and those in which it is inappropriate. Basically, those situations in which the displacements of the host atoms can be represented as involving acoustic phonons yield long-range strain fields analogous to those of the billiard-ball model with the radius of the extra billiard ball being determined by the stiffness of the host lattice and the forces between the added atom and the surrounding host atoms. If the displacements produced by the added atoms are represented as involving primarily optical phonons the displacement pattern is short-ranged and not described by the usual elasticity theory. For example, Vegard's law does not apply in these instances. Such concerns arise in considering the strains induced by interstitial helium in tritides

  3. Preliminary characterization of slow growing rhizobial strains ...

    COMPAQ

    2016-05-18

    May 18, 2016 ... number of nodules was equal to 5.6 nodules per plant for the strain RMB1 from Bousfer site. The intrinsic .... The salt tolerance of rhizobia was tested on YMA plates containing ..... through deep explorations searching for an.

  4. Ductile damage evolution and strain path dependency

    Tasan, C.C.; Hoefnagels, J.P.M.; Peerlings, R.H.J.; Geers, M.G.D.; Horn, ten C.H.L.J.; Vegter, H.; Cueto, E.; Chinesta, F.

    2007-01-01

    Forming limit diagrams are commonly used in sheet metal industry to define the safe forming regions. These diagrams are built to define the necking strains of sheet metals. However, with the rise in the popularity of advance high strength steels, ductile fracture through damage evolution has also

  5. Strain engineering of Dirac cones in graphyne

    Wang, Gaoxue; Kumar, Ashok; Pandey, Ravindra, E-mail: pandey@mtu.edu [Department of Physics, Michigan Technological University, Houghton, Michigan 49931 (United States); Si, Mingsu [Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000 (China)

    2014-05-26

    6,6,12-graphyne, one of the two-dimensional carbon allotropes with the rectangular lattice structure, has two kinds of non-equivalent anisotropic Dirac cones in the first Brillouin zone. We show that Dirac cones can be tuned independently by the uniaxial compressive strain applied to graphyne, which induces n-type and p-type self-doping effect, by shifting the energy of the Dirac cones in the opposite directions. On the other hand, application of the tensile strain results into a transition from gapless to finite gap system for the monolayer. For the AB-stacked bilayer, the results predict tunability of Dirac-cones by in-plane strains as well as the strain applied perpendicular to the plane. The group velocities of the Dirac cones show enhancement in the resistance anisotropy for bilayer relative to the case of monolayer. Such tunable and direction-dependent electronic properties predicted for 6,6,12-graphyne make it to be competitive for the next-generation electronic devices at nanoscale.

  6. Strains and Sprains Are a Pain

    ... lot of pressure on a muscle or you push it too far, such as when lifting a heavy object. Strains can be more likely to happen if you haven't warmed up first to get blood circulating to the muscles. They're also common for someone returning to a sport after the off-season. That first time playing ...

  7. Photoacclimation of cultured strains of the cyanobacterium

    Bañares-España, E.; Kromkamp, J.C.; López-Rodas, V.; Costas, E.; Flores-Moya, A.

    2013-01-01

    The cyanobacterium Microcystis aeruginosa forms blooms that can consist of colonies. We have investigated how M.aeruginosa acclimatizes to changing light conditions such as can occur during blooms. Three different strains were exposed to two irradiance levels: lower (LL) and higher (HL) than the

  8. Strain rate behavior of magnetorheological materials

    Seminuk, Kenneth; Joshi, Vasant; Gump, Jared; Stoltz, Chad; Forbes, Jerry

    2014-01-01

    Strain rate response of two Hydroxyl-terminated Polybutadiene/ Iron (HTPB/Fe) compositions under electromagnetic fields has been investigated using a Split Hopkinson Pressure bar arrangement equipped with aluminum bars. Two HTPB/Fe compositions were developed, the first without plasticizer and the second containing plasticizer. Samples were tested with and without the application of a 0.01 Tesla magnetic field. Strain gauge data taken from the Split Hopkinson Pressure Bar has been used to determine the extent of change in mechanical properties by inducing a mild electromagnetic field onto each sample. Raw data from strain gages was processed using commercial software (Signo) and Excel spreadsheet. It is of particular interest to determine whether the mechanical properties of binder systems can be manipulated by adding ferrous or Magnetostrictive particulates. Data collected from the Split Hopkinson Pressure bar indicate changes in the Mechanical Stress-Strain curves and suggest that the impedance of a binder system can be altered by means of a magnetic field.

  9. Role Strain in University Research Centers

    Boardman, Craig; Bozeman, Barry

    2007-01-01

    One way in which university faculty members' professional lives have become more complex with the advent of contemporary university research centers is that many faculty have taken on additional roles. The authors' concern in this article is to determine the extent to which role strain is experienced by university faculty members who are…

  10. Evolution and Strain Variation in BCG

    Abdallah, Abdallah

    2017-11-07

    BCG vaccines were derived by in vitro passage, during the years 1908–1921, at the Pasteur Institute of Lille. Following the distribution of stocks of BCG to vaccine production laboratories around the world, it was only a few decades before different BCG producers recognized that there were variants of BCG, likely due to different passaging conditions in the different laboratories. This ultimately led to the lyophilization of stable BCG products in the 1950s and 1960s, but not before considerable evolution of the different BCG strains had taken place. The application of contemporary research methodologies has now revealed genomic, transcriptomic and proteomic differences between BCG strains. These molecular differences in part account for phenotypic differences in vitro between BCG strains, such as their variable secretion of antigenic proteins. Yet, the relevance of BCG variability for immunization policy remains elusive. In this chapter we present an overview of what is known about BCG evolution and its resulting strain variability, and provide some speculation as to the potential relevance for a vaccine given to over 100 million newborns each year.

  11. Strain Imaging Using Terahertz Waves and Metamaterials

    2016-11-01

    predictions. 14. SUBJECT TERMS Birefringence, Terahertz Waves, Metamaterials 15. NUMBER OF PAGES 16 16. PRICE CODE 17. SECURITY...opaque objects by using the principles of strain-induced birefringence. 4 III. CONCEPT To overcome the inability of visual light to penetrate ...opaque objects, terahertz radiation was investigated. Longer wavelength EM waves, such as radio waves, have excellent penetration ability but low image

  12. Effective stress coefficient for uniaxial strain condition

    Alam, M.M.; Fabricius, I.L.

    2012-01-01

    one dimensional rock mechanical deformation. We further investigated the effect of boundary condition on the stress dependency of effective stress coefficient and discussed its application in reservoir study. As stress field in the reservoirs are most unlikely to be hydrostatic, effective stress...... determined under uniaxial strain condition will be more relevant in reservoir studies. Copyright 2012 ARMA, American Rock Mechanics Association....

  13. Fibre optic strain sensor: examples of applications

    Kruszewski, J.; Beblowska, M.; Wrzosek, P.

    2006-03-01

    Construction of strain sensor for application in safety systems has been presented. The device consists of sensor's head and source and detector units. The head is made of polymer fiber bends. Designed sensor could be mounted in monitoring place (e.g. under a floor) and controlled by PC unit or could be used as a portable device for a valuable object protection.

  14. Falling balls and simple shearing strain

    Brun, J L; Pacheco, A F

    2006-01-01

    The problem of particles falling under gravity allows us to relate Hamiltonian mechanics to such different subjects as elasticity and fluid mechanics. It is with this in mind that mechanics gives us the opportunity of introducing, in a rather simple and unusual form, some concepts such as vorticity, the incompressibility condition or simple shear strain to physics students at the undergraduate level

  15. What is behind the plastic strain rate?

    Hütter, M.; Grmela, M.; Öttinger, H.C.

    2009-01-01

    The plastic strain rate plays a central role in macroscopic models on elasto-viscoplasticity. In order to discuss the concept behind this quantity, we propose, first, a kinetic toy model to describe the dynamics of sliding layers representative of plastic deformation of single crystalline metals.

  16. Preliminary characterization of Rhizobium strains isolated from ...

    SERVER

    2008-03-18

    Mar 18, 2008 ... residues for animal feed and helps to maintain soil fertility through .... A loopful of agar slopes of the strains assayed for vitamin production was ... B12 Assay Medium, amended with 2 mmol l-1 Ca-pantothenate, biotin and ...

  17. Strain absorbent modules for cavity filling

    1981-04-01

    Strain absorbent modules made from weldmesh panels and helical steel binders can be used, together with timber packing, to support the roof and sides of cavities instead of softwood and hardwood nogs. A description of these modules and a series of load tests and underground trials carried out on the modules is given.

  18. Fano Factor in Strained Graphene Nanoribbon Nanodevices

    Walid Soliman; Mina D.Asham; Adel H.Phillips

    2017-01-01

    We investigate the Fano factor in a strained armchair and zigzag graphene nanoribbon nanodevice under the effect of ac field in a wide range of frequencies at different temperatures (10 K T0 K).This nanodevice is modeled as follows:a graphene nanoribbon is connected to two metallic leads.These two metallic leads operate as a source and a drain.The conducting substance is the gate electrode in this three-terminal nanodevice.Another metallic gate is used to govern the electrostatics and the switching of the graphene nanoribbon channel The substances at the graphene nanoribbon/metal contact are controlled by the back gate.The photon-assisted tunneling probability is deduced by solving the Dirac eigenvalue differential equation in which the Fano factor is expressed in terms of this tunneling probability.The results show that for the investigated nanodevice,the Fano factor decreases as the frequency of the induced ac field increases,while it increases as the temperature increases.In general,the Fano factors for both strained armchair and zigzag graphene nanoribbons are different.This is due to the effect of the uniaxial strain.It is shown that the band structure parameters of graphene nanoribbons at the energy gap,the C-C bond length,the hopping integral,the Fermi energy and the width are modulated by uniaxial strain.This research gives us a promise of the present nanodevice being used for digital nanoelectronics and sensors.

  19. Highly Stretchable, Strain Sensing Hydrogel Optical Fibers.

    Guo, Jingjing; Liu, Xinyue; Jiang, Nan; Yetisen, Ali K; Yuk, Hyunwoo; Yang, Changxi; Khademhosseini, Ali; Zhao, Xuanhe; Yun, Seok-Hyun

    2016-12-01

    A core-clad fiber made of elastic, tough hydrogels is highly stretchable while guiding light. Fluorescent dyes are easily doped into the hydrogel fiber by diffusion. When stretched, the transmission spectrum of the fiber is altered, enabling the strain to be measured and also its location. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Strained Si engineering for nanoscale MOSFETs

    Park, Jea-Gun; Lee, Gon-Sub; Kim, Tae-Hyun; Hong, Seuck-Hoon; Kim, Seong-Je; Song, Jin-Hwan; Shim, Tae-Hun

    2006-01-01

    We have revealed a strain relaxation mechanism for strained Si grown on a relaxed SiGe-on-insulator structure fabricated by the bonding, dislocation sink, or condensation method. Strain relaxation for both the bonding and dislocation sink methods was achieved by grading the Ge concentration; in contrast, the relaxation for the condensation method was achieved through Ge atom condensation during oxidation. In addition, we estimated the surface roughness and threading-dislocation pit density for relaxed SiGe layer fabricated by the bonding, dislocation sink, or condensation method. The surface roughness and threading-dislocation pit density for the bonding, dislocation sink, and condensation methods were 2.45, 0.46, and 0.40 nm and 5.0 x 10 3 , 9 x 10 3 , and 0, respectively. In terms of quality and cost-effectiveness, the condensation method was superior to the bonding and dislocation sink methods for forming strained Si on a relaxed SiGe-on-insulator structure

  1. Simple Numerical Simulation of Strain Measurement

    Tai, H.

    2002-01-01

    By adopting the basic principle of the reflection (and transmission) of a plane polarized electromagnetic wave incident normal to a stack of films of alternating refractive index, a simple numerical code was written to simulate the maximum reflectivity (transmittivity) of a fiber optic Bragg grating corresponding to various non-uniform strain conditions including photo-elastic effect in certain cases.

  2. High strain rate studies in rock

    Grady, D.

    1977-01-01

    Dynamic compression studies using high velocity impact are usually considered to involve a catastrophic process of indeterminate loading rate by which a material is brough to a shock compressed state. Although this is frequently the case, methods are also available to control the rate of strain during the shock compression process. One of the most accurate of these methods makes use of the anomalous nonlinear elastic property of glass to transform an initial shock or step wave input into a ramp wave of known amplitude and duration. Fused silica is the most carefully calibrated material for this purpose and, when placed between the test specimen and the impact projectile, can provide loading strain rates in the range of 10 4 /s to 10 6 /s for final stress states of approximately 3.9 GPa or less.Ramp wave compression experiments have been conducted on dolomite at strain rates of 3 x 10 4 /s. Both initial yielding and subsequent deformation at this strain rate agrees well with previous shock wave studies (epsilon-dotapprox.10 6 /s) and differs substantially from quasi-static measurements (epsilon-dotapprox.10 -4 /s). The ramp wave studies have also uncovered a pressure-induced phase transition in dolomite initiating at 4.0 GPa

  3. Characterizing large strain crush response of redwood

    Cramer, S.M.; Hermanson, J.C.

    1996-12-01

    Containers for the transportation of hazardous and radioactive materials incorporate redwood in impact limiters. Redwood is an excellent energy absorber, but only the most rudimentary information exists on its crush properties. The objectives of the study were to fill the information gap by collecting triaxial load-deformation data for redwood; to use these data to characterize redwood crush, assess current wood failure theories, provide developments toward a complete stress-strain theory for redwood; and to review the literature on strain-rate effects on redwood crush performance. The load-deformation responses of redwood at temperature conditions corresponding to ambient (70 degrees F), 150 degrees F, and -20 degrees F conditions were measured in approximately 100 confined compression tests for crush levels leading to material densification. Data analysis provided a more complete description of redwood crush performance and a basis for assessing proposed general orthotropic stress-strain relationships for redwood. A review of existing literature indicated that strain-rate effects cause at most a 20 percent increase in crush stress parallel to grain

  4. Characterization and monitoring of selected rhizobial strains ...

    SERVER

    2007-06-18

    Jun 18, 2007 ... Fax: +66-44-216345. fixing symbiosis with bacteria known as rhizobia. ... Rhizobial strains were cultured on Yeast-Malt extract agar contain- ing bromthymol blue ... Colony form-ing was observed every day as well as the ...

  5. Preliminary characterization of slow growing rhizobial strains ...

    COMPAQ

    2016-05-18

    May 18, 2016 ... strains had a very slow growth rate in yeast malt (YM) agar medium, forming colonies less than 1 mm in ... dominant genus of symbiotic nitrogen-fixing bacteria ... Single colonies were picked up and checked for purity by.

  6. High strain rate behaviour of polypropylene microfoams

    Gómez-del Río, T.; Garrido, M. A.; Rodríguez, J.; Arencón, D.; Martínez, A. B.

    2012-08-01

    Microcellular materials such as polypropylene foams are often used in protective applications and passive safety for packaging (electronic components, aeronautical structures, food, etc.) or personal safety (helmets, knee-pads, etc.). In such applications the foams which are used are often designed to absorb the maximum energy and are generally subjected to severe loadings involving high strain rates. The manufacture process to obtain polymeric microcellular foams is based on the polymer saturation with a supercritical gas, at high temperature and pressure. This method presents several advantages over the conventional injection moulding techniques which make it industrially feasible. However, the effect of processing conditions such as blowing agent, concentration and microfoaming time and/or temperature on the microstructure of the resulting microcellular polymer (density, cell size and geometry) is not yet set up. The compressive mechanical behaviour of several microcellular polypropylene foams has been investigated over a wide range of strain rates (0.001 to 3000 s-1) in order to show the effects of the processing parameters and strain rate on the mechanical properties. High strain rate tests were performed using a Split Hopkinson Pressure Bar apparatus (SHPB). Polypropylene and polyethylene-ethylene block copolymer foams of various densities were considered.

  7. How strained are carbomeric-cycloalkanes?

    Wodrich, Matthew D; Gonthier, Jérôme F; Steinmann, Stephan N; Corminboeuf, Clémence

    2010-06-24

    The ring strain energies of carbomeric-cycloalkanes (molecules with one or more acetylene spacer units placed into carbon single bonds) are assessed using a series of isodesmic, homodesmotic, and hyperhomodesmotic chemical equations. Isodesmic bond separation reactions and other equations derived from the explicitly defined hierarchy of homodesmotic equations are insufficient for accurately determining these values, since not all perturbing effects (i.e., conjugation and hyperconjugation) are fully balanced. A set of homodesmotic reactions is proposed, which succeeds in balancing all stereoelectronic effects present within the carbomeric rings, allowing for a direct assessment of the strain energies. Values calculated from chemical equations are validated using an increment/additivity approach. The ring strain energy decreases as acetylene units are added, manifesting from the net stabilization gained by opening the C-CH(2)-C angle around the methylene groups and the destabilization arising from bending the C-C identical withC angles of the spacer groups. This destabilization vanishes with increasing parent ring size (i.e., the angle distortion is less in the carbomeric-cyclobutanes than in the carbomeric-cyclopropanes), leading to strain energies near zero for carbo(n)-cyclopentanes and carbo(n)-cyclohexanes.

  8. A constitutive framework for modelling thin incompressible viscoelastic materials under plane stress in the finite strain regime

    Kroon, M.

    2011-11-01

    Rubbers and soft biological tissues may undergo large deformations and are also viscoelastic. The formulation of constitutive models for these materials poses special challenges. In several applications, especially in biomechanics, these materials are also relatively thin, implying that in-plane stresses dominate and that plane stress may therefore be assumed. In the present paper, a constitutive model for viscoelastic materials in the finite strain regime and under the assumption of plane stress is proposed. It is assumed that the relaxation behaviour in the direction of plane stress can be treated separately, which makes it possible to formulate evolution laws for the plastic strains on explicit form at the same time as incompressibility is fulfilled. Experimental results from biomechanics (dynamic inflation of dog aorta) and rubber mechanics (biaxial stretching of rubber sheets) were used to assess the proposed model. The assessment clearly indicates that the model is fully able to predict the experimental outcome for these types of material.

  9. Unsteady Aerodynamic Force Sensing from Measured Strain

    Pak, Chan-Gi

    2016-01-01

    A simple approach for computing unsteady aerodynamic forces from simulated measured strain data is proposed in this study. First, the deflection and slope of the structure are computed from the unsteady strain using the two-step approach. Velocities and accelerations of the structure are computed using the autoregressive moving average model, on-line parameter estimator, low-pass filter, and a least-squares curve fitting method together with analytical derivatives with respect to time. Finally, aerodynamic forces over the wing are computed using modal aerodynamic influence coefficient matrices, a rational function approximation, and a time-marching algorithm. A cantilevered rectangular wing built and tested at the NASA Langley Research Center (Hampton, Virginia, USA) in 1959 is used to validate the simple approach. Unsteady aerodynamic forces as well as wing deflections, velocities, accelerations, and strains are computed using the CFL3D computational fluid dynamics (CFD) code and an MSC/NASTRAN code (MSC Software Corporation, Newport Beach, California, USA), and these CFL3D-based results are assumed as measured quantities. Based on the measured strains, wing deflections, velocities, accelerations, and aerodynamic forces are computed using the proposed approach. These computed deflections, velocities, accelerations, and unsteady aerodynamic forces are compared with the CFL3D/NASTRAN-based results. In general, computed aerodynamic forces based on the lifting surface theory in subsonic speeds are in good agreement with the target aerodynamic forces generated using CFL3D code with the Euler equation. Excellent aeroelastic responses are obtained even with unsteady strain data under the signal to noise ratio of -9.8dB. The deflections, velocities, and accelerations at each sensor location are independent of structural and aerodynamic models. Therefore, the distributed strain data together with the current proposed approaches can be used as distributed deflection

  10. On strain and stress in living cells

    Cox, Brian N.; Smith, David W.

    2014-11-01

    Recent theoretical simulations of amelogenesis and network formation and new, simple analyses of the basic multicellular unit (BMU) allow estimation of the order of magnitude of the strain energy density in populations of living cells in their natural environment. A similar simple calculation translates recent measurements of the force-displacement relation for contacting cells (cell-cell adhesion energy) into equivalent volume energy densities, which are formed by averaging the changes in contact energy caused by a cell's migration over the cell's volume. The rates of change of these mechanical energy densities (energy density rates) are then compared to the order of magnitude of the metabolic activity of a cell, expressed as a rate of production of metabolic energy per unit volume. The mechanical energy density rates are 4-5 orders of magnitude smaller than the metabolic energy density rate in amelogenesis or bone remodeling in the BMU, which involve modest cell migration velocities, and 2-3 orders of magnitude smaller for innervation of the gut or angiogenesis, where migration rates are among the highest for all cell types. For representative cell-cell adhesion gradients, the mechanical energy density rate is 6 orders of magnitude smaller than the metabolic energy density rate. The results call into question the validity of using simple constitutive laws to represent living cells. They also imply that cells need not migrate as inanimate objects of gradients in an energy field, but are better regarded as self-powered automata that may elect to be guided by such gradients or move otherwise. Thus Ġel=d/dt 1/2 >[(C11+C12)ɛ02+2μγ02]=(C11+C12)ɛ0ɛ˙0+2μγ0γ˙0 or Ġel=ηEɛ0ɛ˙0+η‧Eγ0γ˙0 with 1.4≤η≤3.4 and 0.7≤η‧≤0.8 for Poisson's ratio in the range 0.2≤ν≤0.4 and η=1.95 and η‧=0.75 for ν=0.3. The spatial distribution of shear strains arising within an individual cell as cells slide past one another during amelogenesis is not known

  11. Recent advances in echocardiography: strain and strain rate imaging [version 1; referees: 3 approved

    Oana Mirea

    2016-04-01

    Full Text Available Deformation imaging by echocardiography is a well-established research tool which has been gaining interest from clinical cardiologists since the introduction of speckle tracking. Post-processing of echo images to analyze deformation has become readily available at the fingertips of the user. New parameters such as global longitudinal strain have been shown to provide added diagnostic value, and ongoing efforts of the imaging societies and industry aimed at harmonizing methods will improve the technique further. This review focuses on recent advances in the field of echocardiographic strain and strain rate imaging, and provides an overview on its current and potential future clinical applications.

  12. Enzyme markers in inbred rat strains: genetics of new markers and strain profiles.

    Adams, M; Baverstock, P R; Watts, C H; Gutman, G A

    1984-08-01

    Twenty-six inbred strains of the laboratory rat (Rattus norvegicus) were examined for electrophoretic variation at an estimated 97 genetic loci. In addition to previously documented markers, variation was observed for the enzymes aconitase, aldehyde dehydrogenase, and alkaline phosphatase. The genetic basis of these markers (Acon-1, Ahd-2, and Akp-1) was confirmed. Linkage analysis between 35 pairwise comparisons revealed that the markers Fh-1 and Pep-3 are linked. The strain profiles of the 25 inbred strains at 11 electrophoretic markers are given.

  13. Matrix production and organization by endothelial colony forming cells in mechanically strained engineered tissue constructs.

    Nicky de Jonge

    Full Text Available AIMS: Tissue engineering is an innovative method to restore cardiovascular tissue function by implanting either an in vitro cultured tissue or a degradable, mechanically functional scaffold that gradually transforms into a living neo-tissue by recruiting tissue forming cells at the site of implantation. Circulating endothelial colony forming cells (ECFCs are capable of differentiating into endothelial cells as well as a mesenchymal ECM-producing phenotype, undergoing Endothelial-to-Mesenchymal-transition (EndoMT. We investigated the potential of ECFCs to produce and organize ECM under the influence of static and cyclic mechanical strain, as well as stimulation with transforming growth factor β1 (TGFβ1. METHODS AND RESULTS: A fibrin-based 3D tissue model was used to simulate neo-tissue formation. Extracellular matrix organization was monitored using confocal laser-scanning microscopy. ECFCs produced collagen and also elastin, but did not form an organized matrix, except when cultured with TGFβ1 under static strain. Here, collagen was aligned more parallel to the strain direction, similar to Human Vena Saphena Cell-seeded controls. Priming ECFC with TGFβ1 before exposing them to strain led to more homogenous matrix production. CONCLUSIONS: Biochemical and mechanical cues can induce extracellular matrix formation by ECFCs in tissue models that mimic early tissue formation. Our findings suggest that priming with bioactives may be required to optimize neo-tissue development with ECFCs and has important consequences for the timing of stimuli applied to scaffold designs for both in vitro and in situ cardiovascular tissue engineering. The results obtained with ECFCs differ from those obtained with other cell sources, such as vena saphena-derived myofibroblasts, underlining the need for experimental models like ours to test novel cell sources for cardiovascular tissue engineering.

  14. Informal eldercare and work-related strain.

    Trukeschitz, Birgit; Schneider, Ulrike; Mühlmann, Richard; Ponocny, Ivo

    2013-03-01

    In light of an aging workforce, reconciling informal eldercare and paid work becomes increasingly pertinent. This article investigates the association between informal eldercare and work-related strain and tests for both the "competing demands" and "expansion" hypotheses. The sample of 938 Austrian employees consisted of employees caring for older relatives and a control group of employees without eldercare obligations. We ran a Tobit regression model on work-related strain with different measures of informal eldercare as explanatory variables and controls for both personal and workplace characteristics. Accounting for different characteristics of eldercare within one estimation model revealed that informal eldercare was associated with work-related strain in 2 ways, that is, it increased with both care hours and subjective care burden. However, after controlling for these burdensome attributes of eldercare, the carer status as such was found to be negatively associated with work-related strain. In addition and independently of care commitments, work-related factors, such as advanced skills and job motivation, reduced work-related strain. This article lends support to both the "competing demands" and the "expansion" hypotheses. Commitment to eldercare can enhance work-related outcomes but entails work-related problems if care burden and time demands of eldercare are substantial. Thus, workers with eldercare responsibilities cannot be considered less productive from the outset. An individual assessment of their situation, considering the care and work setting, is required. Findings from this study support the design of workplace initiatives to uphold workers' productivity in general and bring specific attention to policies alleviating workers' eldercare burden.

  15. Strain rate effects for spallation of concrete

    Häussler-Combe, Ulrich; Panteki, Evmorfia; Kühn, Tino

    2015-09-01

    Appropriate triaxial constitutive laws are the key for a realistic simulation of high speed dynamics of concrete. The strain rate effect is still an open issue within this context. In particular the question whether it is a material property - which can be covered by rate dependent stress strain relations - or mainly an effect of inertia is still under discussion. Experimental and theoretical investigations of spallation of concrete specimen in a Hopkinson Bar setup may bring some evidence into this question. For this purpose the paper describes the VERD model, a newly developed constitutive law for concrete based on a damage approach with included strain rate effects [1]. In contrast to other approaches the dynamic strength increase is not directly coupled to strain rate values but related to physical mechanisms like the retarded movement of water in capillary systems and delayed microcracking. The constitutive law is fully triaxial and implemented into explicit finite element codes for the investigation of a wide range of concrete structures exposed to impact and explosions. The current setup models spallation experiments with concrete specimen [2]. The results of such experiments are mainly related to the dynamic tensile strength and the crack energy of concrete which may be derived from, e.g., the velocity of spalled concrete fragments. The experimental results are compared to the VERD model and two further constitutive laws implemented in LS-Dyna. The results indicate that both viscosity and retarded damage are required for a realistic description of the material behaviour of concrete exposed to high strain effects [3].

  16. Strain rate effects for spallation of concrete

    Häussler-Combe Ulrich

    2015-01-01

    Full Text Available Appropriate triaxial constitutive laws are the key for a realistic simulation of high speed dynamics of concrete. The strain rate effect is still an open issue within this context. In particular the question whether it is a material property – which can be covered by rate dependent stress strain relations – or mainly an effect of inertia is still under discussion. Experimental and theoretical investigations of spallation of concrete specimen in a Hopkinson Bar setup may bring some evidence into this question. For this purpose the paper describes the VERD model, a newly developed constitutive law for concrete based on a damage approach with included strain rate effects [1]. In contrast to other approaches the dynamic strength increase is not directly coupled to strain rate values but related to physical mechanisms like the retarded movement of water in capillary systems and delayed microcracking. The constitutive law is fully triaxial and implemented into explicit finite element codes for the investigation of a wide range of concrete structures exposed to impact and explosions. The current setup models spallation experiments with concrete specimen [2]. The results of such experiments are mainly related to the dynamic tensile strength and the crack energy of concrete which may be derived from, e.g., the velocity of spalled concrete fragments. The experimental results are compared to the VERD model and two further constitutive laws implemented in LS-Dyna. The results indicate that both viscosity and retarded damage are required for a realistic description of the material behaviour of concrete exposed to high strain effects [3].

  17. Neonatal and maternal outcomes comparing women undergoing two in vitro fertilization (IVF) singleton pregnancies and women undergoing one IVF twin pregnancy.

    Sazonova, Antonina; Källen, Karin; Thurin-Kjellberg, Ann; Wennerholm, Ulla-Britt; Bergh, Christina

    2013-03-01

    To compare outcomes for women undergoing two in vitro fertilization (IVF) pregnancies with singletons and women undergoing one IVF twin pregnancy. The concept of single-embryo transfer in IVF has reduced the risks of both maternal and neonatal complications, but there is still a discussion of whether or not twins are a desired outcome of IVF. Registry study. Not applicable. All reported twins after IVF with double-embryo transfer (n = 1,982) and their mothers (n = 991) and all mothers (n = 921) who gave birth to two IVF singletons (n = 1,842). None. Maternal and neonatal outcomes including severe neonatal morbidity. Preterm birth, very preterm birth, low birth weight, very low birth weight, and small for gestational age were dramatically increased for IVF twins compared with two IVF singletons with the same mother, with adjusted odds ratios from 4 to 16. Significantly higher rates of respiratory complications, sepsis, and jaundice were detected among the IVF twins. Significantly higher rates of preeclampsia, preterm premature rupture of the membranes, and cesarean section were observed for IVF twin pregnancies. The neonatal and maternal outcomes were dramatically better for women undergoing two IVF singleton pregnancies compared with one IVF twin pregnancy after double-embryo transfer. These results support single-embryo transfer to minimize the risks associated with twin pregnancies. Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  18. Risk of Ionizing Radiation in Women of Childbearing Age undergoing Radiofrequency Ablation

    Lima, Gustavo Glotz de; Gomes, Daniel Garcia; Gensas, Caroline Saltz; Simão, Mariana Fernandez; Rios, Matheus N.; Pires, Leonardo Martins; Kruse, Marcelo Lapa; Leiria, Tiago Luiz Luz

    2013-01-01

    The International Commission of Radiology recommends a pregnancy screening test to all female patients of childbearing age who will undergo a radiological study. Radiation is known to be teratogenic and its effect is cumulative. The teratogenic potential starts at doses close to those used during these procedures. The prevalence of positive pregnancy tests in patients undergoing electrophysiological studies and/or catheter ablation in our midst is unknown. To evaluate the prevalence of positive pregnancy tests in female patients referred for electrophysiological study and/or radiofrequency ablation. Cross-sectional study analyzing 2,966 patients undergoing electrophysiological study and/or catheter ablation, from June 1997 to February 2013, in the Institute of Cardiology of Rio Grande do Sul. A total of 1490 procedures were performed in women, of whom 769 were of childbearing age. All patients were screened with a pregnancy test on the day before the procedure. Three patients tested positive, and were therefore unable to undergo the procedure. The prevalence observed was 3.9 cases per 1,000 women of childbearing age. Because of their safety and low cost, pregnancy screening tests are indicated for all women of childbearing age undergoing radiological studies, since the degree of ionizing radiation needed for these procedures is very close to the threshold for teratogenicity, especially in the first trimester, when the signs of pregnancy are not evident

  19. Influences on decision-making for undergoing plastic surgery: a mental models and quantitative assessment.

    Darisi, Tanya; Thorne, Sarah; Iacobelli, Carolyn

    2005-09-01

    Research was conducted to gain insight into potential clients' decisions to undergo plastic surgery, their perception of benefits and risks, their judgment of outcomes, and their selection of a plastic surgeon. Semistructured, open-ended interviews were conducted with 60 people who expressed interest in plastic surgery. Qualitative analysis revealed their "mental models" regarding influences on their decision to undergo plastic surgery and their choice of a surgeon. Interview results were used to design a Web-based survey in which 644 individuals considering plastic surgery responded. The desire for change was the most direct motivator to undergo plastic surgery. Improvements to physical well-being were related to emotional and social benefits. When prompted about risks, participants mentioned physical, emotional, and social risks. Surgeon selection was a critical influence on decisions to undergo plastic surgery. Participants gave considerable weight to personal consultation and believed that finding the "right" plastic surgeon would minimize potential risks. Findings from the Web-based survey were similar to the mental models interviews in terms of benefit ratings but differed in risk ratings and surgeon selection criteria. The mental models interviews revealed that interview participants were thoughtful about their decision to undergo plastic surgery and focused on finding the right plastic surgeon.

  20. Risk of Ionizing Radiation in Women of Childbearing Age undergoing Radiofrequency Ablation

    Lima, Gustavo Glotz de, E-mail: gglima.pesquisa@gmail.com; Gomes, Daniel Garcia; Gensas, Caroline Saltz; Simão, Mariana Fernandez; Rios, Matheus N.; Pires, Leonardo Martins; Kruse, Marcelo Lapa; Leiria, Tiago Luiz Luz [Instituto de Cardiologia, Fundação Universitária de Cardiologia, Porto Alegre, RS (Brazil)

    2013-11-15

    The International Commission of Radiology recommends a pregnancy screening test to all female patients of childbearing age who will undergo a radiological study. Radiation is known to be teratogenic and its effect is cumulative. The teratogenic potential starts at doses close to those used during these procedures. The prevalence of positive pregnancy tests in patients undergoing electrophysiological studies and/or catheter ablation in our midst is unknown. To evaluate the prevalence of positive pregnancy tests in female patients referred for electrophysiological study and/or radiofrequency ablation. Cross-sectional study analyzing 2,966 patients undergoing electrophysiological study and/or catheter ablation, from June 1997 to February 2013, in the Institute of Cardiology of Rio Grande do Sul. A total of 1490 procedures were performed in women, of whom 769 were of childbearing age. All patients were screened with a pregnancy test on the day before the procedure. Three patients tested positive, and were therefore unable to undergo the procedure. The prevalence observed was 3.9 cases per 1,000 women of childbearing age. Because of their safety and low cost, pregnancy screening tests are indicated for all women of childbearing age undergoing radiological studies, since the degree of ionizing radiation needed for these procedures is very close to the threshold for teratogenicity, especially in the first trimester, when the signs of pregnancy are not evident.