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Sample records for volume diameter decreased

  1. Diameter structure modeling and the calculation of plantation volume of black poplar clones

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    Andrašev Siniša

    2004-01-01

    Full Text Available A method of diameter structure modeling was applied in the calculation of plantation (stand volume of two black poplar clones in the section Aigeiros (Duby: 618 (Lux and S1-8. Diameter structure modeling by Weibull function makes it possible to calculate the plantation volume by volume line. Based on the comparison of the proposed method with the existing methods, the obtained error of plantation volume was less than 2%. Diameter structure modeling and the calculation of plantation volume by diameter structure model, by the regularity of diameter distribution, enables a better analysis of the production level and assortment structure and it can be used in the construction of yield and increment tables.

  2. Inter-observer variation in ultrasound measurement of the volume and diameter of thyroid nodules

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    Choi, Young Jun; Baek, Jung Hwan; Hong, Min Ji; Lee, Jeong Hyun [Dept. of Radiology, and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    2015-06-15

    Thyroid nodule measurement using ultrasonography (US) is widely performed in various clinical scenarios. The purpose of this study was to evaluate inter-observer variation in US measurement of the volume and maximum diameter of thyroid nodules. This retrospective study included 73 consecutive patients with 85 well-defined thyroid nodules greater than 1 cm in their maximum diameter. US examinations were independently performed by using standardized measurement methods, conducted by two clinically experienced thyroid radiologists. The maximum nodule diameter and nodule volume, calculated from nodule diameters using the ellipsoid formula, were obtained by each reader. Inter-observer variations in volume and maximum diameter were determined using 95% Bland-Altman limits of agreement. The degree of inter-observer variations in volumes and the maximum diameters were compared using the Student's t test, between nodules < 2 cm in maximum diameter and those with > or = 2 cm. The mean inter-observer difference in measuring the nodule volume was -1.6%, in terms of percentage of the nodule volume, and the 95% limit of agreement was +/- 13.1%. For maximum nodule diameter, the mean inter-observer difference was -0.6%, in terms of percentage of the nodule diameter, and the 95% limit of agreement was +/- 7.3%. Inter-observer variation in volume was greater in nodules of < 2 cm in maximum diameter, compared to the larger nodules (p = 0.035). However, no statistically significant difference was noted between the two groups regarding maximum nodule diameters (p = 0.511). Any differences smaller than 13.1% and 7.3% in volume and maximum diameter, respectively, measured by using US for well-defined thyroid nodules of > 1 cm should not be considered as a real change in size.

  3. Follow-up on Small Abdominal Aortic Aneurysms Using Three Dimensional Ultrasound: Volume Versus Diameter.

    Science.gov (United States)

    Ghulam, Q M; Bredahl, K K; Lönn, L; Rouet, L; Sillesen, H H; Eiberg, J P

    2017-10-01

    Rupture risk in abdominal aortic aneurysms (AAAs) is assessed using AAA diameter; yet 10% of ruptures occur in a small aneurysm. This underlines the inadequacy of diameter as a standalone parameter. In this prospective follow-up study, ultrasound determined aneurysm diameter was compared with aneurysm volume determined by three dimensional ultrasound (3D-US) in a group of 179 AAAs. This was a prospective cohort study with repeated diameter and volume measurements by 3D-US. In total, 179 patients with small infrarenal AAAs (diameter 30-55 mm) were enrolled consecutively. At enrolment and at 12 month follow-up, maximum diameter, using dual plane technique, and three dimensional volume were measured. Based on a previous accuracy study, significant change in diameter and volume were defined as an increase exceeding the known range of variability (ROV) of each US technique; ±3.7 mm and ±8.8 mL, respectively. Post-hoc Kaplan-Meier analysis was performed to estimate time to conversion to treatment after the conclusion of the follow-up period between two groups. In total, 125 patients (70%) had an unchanged diameter during follow-up. In this group, 50 patients (40%) had an increasing aortic volume. Forty-five (83%) of the 54 patients with an increasing aortic diameter showed a corresponding volume increase. During a median follow-up of 367 days (364-380 days), a mean increase in diameter of 2.7 mm (±2.6 mm) and a mean increase in volume of 11.6 mL (±9.9 mL) were recorded. In post-hoc analysis, it was found that more AAAs with a stable diameter and a growing volume than AAAs with a stable diameter and volume were undergoing aortic repair during follow-up, based on the maximum diameter. In this cohort of small AAAs, 40% of patients with a stable diameter had an increasing volume at 12 month follow-up. From this perspective, 3D-US could have a future supplemental role in AAA surveillance programmes. Copyright © 2017 European Society for Vascular Surgery. Published

  4. Decreased mean platelet volume in panic disorder

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    Göğçegöz Gül I

    2014-09-01

    Full Text Available Işil Göğçegöz Gül, Gül Eryilmaz, Eylem Özten, Gökben Hizli Sayar Neuropsychiatry Health, Practice, and Research Center, Uskudar University, Istanbul, Turkey Aim: The relationship between psychological stress and platelet activation has been widely studied. It is well known that platelets may reflect certain biochemical changes that occur in the brain when different mental conditions occur. Platelet 5-hydroxytryptamine (5-HT is also extensively studied in psychiatry. The mean platelet volume (MPV, the accurate measure of platelet size, has been considered a marker and determinant of platelet function. The aim of the present study was to search for any probable difference in the MPV of subjects with panic disorder (PD.Methods: A total of 37 drug-free subjects, aged 18 to 65 years, diagnosed with PD, with or without agoraphobia, according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth edition (DSM-IV criteria and 45 healthy control subjects were included in the study. Platelet count and MPV were measured and recorded for each subject.Results: There were no statistically significant differences between groups in terms of female/male ratio, age, or body mass index between the PD group and control group (P=0.91, P=0.82, and P=0.93, respectively. The MPV was found to be significantly lower in the PD group compared with the control group (8.8±0.9 fL vs 9.2±0.8 fL; P=0.02. All the participants had MPV values in the standard range of 6.9–10.8 fL.Conclusion: We concluded that abnormalities of the 5-HT1A receptor function in the central nervous system of subjects with a diagnosis of PD are also mirrored in as an alteration in platelet activity. Measurements of platelet activity may be used as a tool for neuropsychiatric and psychopharmacological research and for studying how certain mental diseases and medications affect the central nervous system. Keywords: 5-HT, thrombocyte, anxiety 

  5. Shear-induced Volume Decrease in MDCK Cells

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    Heo, Jinseok; Sachs, Frederick; Wang, Jianbin; Hua, Susan Z.

    2013-01-01

    Using a microfluidic cell volume sensor we measured the change in the cell volume of Madin-Darby Canine Kidney (MDCK) cells induced by shear stress. An increase in shear stress from 0.2 to 2.0 dyn/cm2 resulted in a volume decrease to a steady state volume ~ 20 – 30 % smaller than the initial resting cell volume. Independent experiments based on fluorescence quenching confirmed the volume reduction. This shear-induced cell shrinkage was irreversible on the time scale of the experiment (~ 30 min). Treatment of 0.1 μM Hg2+ significantly inhibited the volume decrease, suggesting that the shear-induced cell shrinkage is associated with water efflux through aquaporins. The volume decrease cannot be inhibited by 75 mM TEA, 100 μM DIDS, or 100 μM Gd3+ suggesting that volume reduction is not directly mediated by K+ and Cl− channels that typically function during regulatory volume decrease (RVD), nor is it through cationic stretch-activated ion channels (SACs). The process also appears to be Ca2+ independent because it was insensitive to intracellular Ca2+ level. Since cell volume is determined by the intracellular water content, we postulate that the shear induced reductions in cell volume may arise from increased intracellular hydrostatic pressure as the cell is deformed under flow, which promotes the efflux of water. The increase in internal pressure in a deformable object under the flow is supported by the finite element mechanical model. PMID:22759987

  6. ON THE TOPOLOGY, VOLUME, DIAMETER AND GAUSS MAP IMAGE OF SUBMANIFOLDS IN A SPHERE

    Institute of Scientific and Technical Information of China (English)

    WU BINGYE

    2004-01-01

    In this paper, the author uses Gauss map to study the topology, volume and diameter of submanifolds in a sphere. It is proved that if there exist ε, 1 ≥ε≥ 0 and a fixed unit simple p-vector a such that the Gauss map g of an n-dimensional complete to Sn, and the volume and diameter of M satisfy εnvol(Sn) ≤vol(M) ≤ vol(Sn)/εand επ≤diam(M) ≤π/ε, respectively. The author also characterizes the case where these inequalities become equalities. As an application, a differential sphere theorem for compact submanifolds in a sphere is obtained.

  7. The blood pressure-induced diameter response of retinal arterioles decreases with increasing diabetic maculopathy

    DEFF Research Database (Denmark)

    Frederiksen, Christian Alcaraz; Jeppesen, Peter; Knudsen, Søren Tang;

    2006-01-01

    were measured using the Retinal Vessel Analyzer (RVA, Imedos, Germany) before, during, and after an increase in the blood pressure induced by isometric exercise. Additionally, the retinal thickness was measured using optical coherence tomography scanning. RESULTS: The arterioles contracted during......BACKGROUND: The aim of the study was to compare the diameter response of retinal arterioles and retinal thickness in patients with different stages of diabetic maculopathy during an increase in the arterial blood pressure. METHODS: Four groups each consisting of 19 individuals were studied. Group...

  8. Comparison of volume and diameter measurement in assessing small abdominal aortic aneurysm expansion examined using computed tomographic angiography

    Energy Technology Data Exchange (ETDEWEB)

    Parr, Adam; Jayaratne, Chanaka; Buttner, Petra [Vascular Biology Unit, James Cook University, Townsville, Queensland 4811 (Australia); Golledge, Jonathan, E-mail: Jonathan.Golledge@jcu.edu.au [Vascular Biology Unit, James Cook University, Townsville, Queensland 4811 (Australia)

    2011-07-15

    Aim: First we aimed to assess the reproducibility of a computer tomography angiography (CTA) based technique for measuring infra-renal aortic volume and diameter. Second we sought to investigate whether changes in aortic volume and diameter were similar during follow-up. Materials and methods: A prospective series of 57 patients, with aortic diameter initially measuring between 25 and 55 mm, were assessed with 2 CTAs a median of 14 months apart. Aortic volume and maximum diameter (both axial and orthogonal) were measured by a semi-automated workstation protocol based on previously defined techniques. Intra- and inter-observer reproducibility were assessed by repeat assessment of the initial CTA images of the first 33 patients included in the study, in order to estimate the 95% limits of agreements. Changes in aortic dimensions between the first and follow-up CTA, were defined for volume and diameter separately as changes greater than their respective 95% limits of agreement. Results: Reproducibility of aortic volume and diameter was excellent with an average coefficient of variation <4%. The median (inter-quartile range) increases in total volume, orthogonal and axial diameters were 4.9 cm{sup 3} (0.01-14.18), 1.2 mm (0.40-3.50) and 1.4 mm (-0.15 to 3.55) respectively. Forty-two percent of patients who had increased aortic volume above the 95% limit of agreement did not display corresponding axial or orthogonal diameter changes. Conclusions: Infra-renal total aortic volume, axial and orthogonal diameter can all be measured reproducibly from CTA. Aortic volume changes are not always reflected by similar changes in diameter and therefore provide complementary information when assessing AAA expansion over time.

  9. Retinal vessel diameters decrease with macular ganglion cell layer thickness in autosomal dominant optic atrophy and in healthy subjects

    DEFF Research Database (Denmark)

    Rönnbäck, Cecilia; Grønskov, Karen; Larsen, Michael

    2014-01-01

    PURPOSE: To investigate retinal trunk vessel diameters in subjects with autosomal dominant optic atrophy (ADOA) and mutation-free healthy relatives. METHODS: This cross-sectional study included 52 ADOA patients with the optic atrophy 1 (OPA1) exon 28 (c.2826_2836delinsGGATGCTCCA) mutation (age 8...... ganglion cell-inner plexiform layer (GC-IPL) thickness (p = 0.0017 and p = 0.0057, respectively). CONCLUSION: Narrow retinal arteries and veins were associated not only with the severity of ADOA but with ganglion cell volume in patients with ADOA and in healthy subjects. This suggests that narrow vessels...

  10. A predictive nondestructive model for the covariation of tree height, diameter, and stem volume scaling relationships

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    Zhang, Zhongrui; Zhong, Quanlin; Niklas, Karl J.; Cai, Liang; Yang, Yusheng; Cheng, Dongliang

    2016-08-01

    Metabolic scaling theory (MST) posits that the scaling exponents among plant height H, diameter D, and biomass M will covary across phyletically diverse species. However, the relationships between scaling exponents and normalization constants remain unclear. Therefore, we developed a predictive model for the covariation of H, D, and stem volume V scaling relationships and used data from Chinese fir (Cunninghamia lanceolata) in Jiangxi province, China to test it. As predicted by the model and supported by the data, normalization constants are positively correlated with their associated scaling exponents for D vs. V and H vs. V, whereas normalization constants are negatively correlated with the scaling exponents of H vs. D. The prediction model also yielded reliable estimations of V (mean absolute percentage error = 10.5 ± 0.32 SE across 12 model calibrated sites). These results (1) support a totally new covariation scaling model, (2) indicate that differences in stem volume scaling relationships at the intra-specific level are driven by anatomical or ecophysiological responses to site quality and/or management practices, and (3) provide an accurate non-destructive method for predicting Chinese fir stem volume.

  11. A predictive nondestructive model for the covariation of tree height, diameter, and stem volume scaling relationships.

    Science.gov (United States)

    Zhang, Zhongrui; Zhong, Quanlin; Niklas, Karl J; Cai, Liang; Yang, Yusheng; Cheng, Dongliang

    2016-08-24

    Metabolic scaling theory (MST) posits that the scaling exponents among plant height H, diameter D, and biomass M will covary across phyletically diverse species. However, the relationships between scaling exponents and normalization constants remain unclear. Therefore, we developed a predictive model for the covariation of H, D, and stem volume V scaling relationships and used data from Chinese fir (Cunninghamia lanceolata) in Jiangxi province, China to test it. As predicted by the model and supported by the data, normalization constants are positively correlated with their associated scaling exponents for D vs. V and H vs. V, whereas normalization constants are negatively correlated with the scaling exponents of H vs. D. The prediction model also yielded reliable estimations of V (mean absolute percentage error = 10.5 ± 0.32 SE across 12 model calibrated sites). These results (1) support a totally new covariation scaling model, (2) indicate that differences in stem volume scaling relationships at the intra-specific level are driven by anatomical or ecophysiological responses to site quality and/or management practices, and (3) provide an accurate non-destructive method for predicting Chinese fir stem volume.

  12. Cell Volume Regulation and Apoptotic Volume Decrease in Rat Distal Colon Superficial Enterocytes

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    Stefania Antico

    2013-12-01

    Full Text Available Background: The colon epithelium is physiologically exposed to osmotic stress, and the activation of cell volume regulation mechanisms is essential in colonocyte physiology. Moreover, colon is characterized by a high apoptotic rate of mature cells balancing the high division rate of stem cells. Aim: The aim of the present work was to investigate the main cell volume regulation mechanisms in rat colon surface colonocytes and their role in apoptosis. Methods: Cell volume changes were measured by light microscopy and video imaging on colon explants; apoptosis sign appearance was monitored by confocal microscopy on annexin V/propidium iodide labeled explants. Results: Superficial colonocytes showed a dynamic regulation of their cell volume during anisosmotic conditions with a Regulatory Volume Increase (RVI response following hypertonic shrinkage and Regulatory Volume Decrease (RVD response following hypotonic swelling. RVI was completely inhibited by bumetanide, while RVD was completely abolished by high K+ or iberiotoxin treatment and by extracellular Ca2+ removal. DIDS incubation was also able to affect the RVD response. When colon explants were exposed to H2O2 as apoptotic inducer, colonocytes underwent an isotonic volume decrease ascribable to Apoptotic Volume Decrease (AVD within about four hours of exposure. AVD was shown to precede annexin V positivity. It was also inhibited by high K+ or iberiotoxin treatment. Interestingly, treatment with iberiotoxin significantly inhibited apoptosis progression. Conclusions: In rat superficial colonocytes K+ efflux through high conductance Ca2+-activated K+ channels (BK channels was demonstrated to be the main mechanism of RVD and to plays also a crucial role in the AVD process and in the progression of apoptosis.

  13. Glycerol decreases the volume and compressibility of protein interior.

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    Priev, A; Almagor, A; Yedgar, S; Gavish, B

    1996-02-20

    The addition of hydrogen-bonded cosolvents to aqueous solutions of proteins is known to modify both thermodynamic and dynamic properties of the proteins in a variety of ways. Previous studies suggest that glycerol reduces the free volume and compressibility of proteins. However, there is no directly measured evidence for that. We have measured the apparent specific volume (V) and adiabatic compressibility (K) of a number of proteins, sugars, and amino acids in water and in 30% glycerol at pH 7.4 and 30 degrees C. The values of V and K in water and their changes induced by glycerol were extrapolated to the limit of infinite solute size. The main results were the following: (a) glycerol decreases V and K of proteins, but increases it for amino acids; (b) the V and K values of the protein interior in water were found to be 0.784 +/- 0.026 mL/g and (12.8 +/- 2.5) x 10(-6) mL/g x atm, where the glycerol reduces these values by 8 and 32%, respectively; (c) the coefficient of adiabatic compressibility of the structural component of proteins affected by the glycerol is estimated to be (50 +/- 10) x 10(-6) atm(-1), which is comparable to that of water. We propose that the glycerol induces a release of the so-called "lubricant" water, which maintains conformational flexibility by keeping apart neighboring segments of the polypeptide chain. This is expected to lead to the collapsing of the voids containing the water as well as to increase intramolecular bonding, which explains the observed effect.

  14. Left Atrial Volume and Pulmonary Artery Diameter Are Noninvasive Measures of Age-Related Diastolic Dysfunction in Mice.

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    Medrano, Guillermo; Hermosillo-Rodriguez, Jesus; Pham, Thuy; Granillo, Alejandro; Hartley, Craig J; Reddy, Anilkumar; Osuna, Patricia Mejia; Entman, Mark L; Taffet, George E

    2016-09-01

    Impaired cardiac diastolic function occurs with aging in many species and may be difficult to measure noninvasively. In humans, left atrial (LA) volume is a robust measure of chronic diastolic function as the LA is exposed to increased left ventricular filling pressures. We hypothesized that LA volume would be a useful indicator of diastolic function in aging mice. Further, we asked whether pressures were propagated backwards affecting pulmonary arteries (PAs) and right ventricle (RV). We measured LA, PA, and RV infundibulum dimensions with echocardiography and used mouse-specific Doppler systems and pressure catheters for noninvasive and invasive measures. As C57BL/6 mice aged from 3 to 29-31 months, LA volume almost tripled. LA volume increases correlated with traditional diastolic function measures. Within groups of 14- and 31-month-old mice, LA volume correlated with diastolic function measured invasively. In serial studies, mice evaluated at 20 and 24 months showed monotonic increases in LA volume; other parameters changed less predictably. PA diameters, larger in 30-month-old mice than 6-month-old mice, correlated with LA volumes. Noninvasive LA volume and PA diameter assessments are useful and state independent measures of diastolic function in mice, correlating with other measures of diastolic dysfunction in aging. Furthermore, serial measurements over 4 months demonstrated consistent increases in LA volume suitable for longitudinal cardiac aging studies.

  15. Dependence of alpha particle track diameter on the free volume holes size using positron annihilation lifetime technique

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    El-Gamal, S.; Abdalla, Ayman M.; Abdel-Hady, E. E.

    2015-09-01

    The alpha particle track diameter dependence of the free volume holes size (Vf) in DAM-ADC and CR-39 nuclear track detectors was investigated using positron annihilation lifetime technique. The effect of temperature on the alpha particle track diameter and free volume were also investigated in the T-range (RT-130 °C). The obtained results revealed that the values of ortho-positronium lifetime τ3 and Vf increases while I3 slightly increases as T increases for the two detectors. The values of τ3, Vf and I3 are higher in CR-39 than DAM-ADC. The interpretation of obtained results is based on the fact that increasing T leads to significant enhancement of thermal expansion of the polymer matrix and consequently Vf increases. The track diameter increases as T increases. This can be explained by the fact that the increase in T increases the crystal size and Vf in the polymer. A relationship between Vf and the alpha particle track diameter was obtained. Moreover results of detector irradiation, along with free volume evaluation are addressed and thoroughly discussed.

  16. Dependence of alpha particle track diameter on the free volume holes size using positron annihilation lifetime technique

    Energy Technology Data Exchange (ETDEWEB)

    El-Gamal, S. [Physics Department, Faculty of Education, Ain Shams University, Roxy, 11711 Cairo (Egypt); Abdalla, Ayman M., E-mail: aymanabdalla62@hotmail.com [Physics Department, Faculty of Arts and Sciences, Najran University, Najran (Saudi Arabia); Centre for Advanced Materials and Nano-Engineering, Najran University, Najran 11001 (Saudi Arabia); Abdel-Hady, E.E. [Physics Department, Faculty of Science, Minia University, BO 61519, Minia (Egypt)

    2015-09-15

    The alpha particle track diameter dependence of the free volume holes size (V{sub f}) in DAM–ADC and CR-39 nuclear track detectors was investigated using positron annihilation lifetime technique. The effect of temperature on the alpha particle track diameter and free volume were also investigated in the T-range (RT-130 °C). The obtained results revealed that the values of ortho-positronium lifetime τ{sub 3} and V{sub f} increases while I{sub 3} slightly increases as T increases for the two detectors. The values of τ{sub 3}, V{sub f} and I{sub 3} are higher in CR-39 than DAM–ADC. The interpretation of obtained results is based on the fact that increasing T leads to significant enhancement of thermal expansion of the polymer matrix and consequently V{sub f} increases. The track diameter increases as T increases. This can be explained by the fact that the increase in T increases the crystal size and V{sub f} in the polymer. A relationship between V{sub f} and the alpha particle track diameter was obtained. Moreover results of detector irradiation, along with free volume evaluation are addressed and thoroughly discussed.

  17. Food intake in relation to pouch volume, stoma diameter, and pouch emptying after gastroplasty for morbid obesity

    DEFF Research Database (Denmark)

    Andersen, T; Pedersen, B H; Henriksen, Jens Henrik Sahl

    1988-01-01

    This study investigated possible determinants of food intake change after gastroplastry. Preoperatively and 6 and 12 months postoperatively, 27 morbidly obese patients were prospectively examined with 7-day food registration and radiologic measurement of pouch volume and stoma diameter. Pouch...... emptying was determined as the mean transit time by a scintigraphic method. None of the measured variables was found to influence the change in food intake taking place during the first 6 months, when most of the weight loss was observed. Between 6 and 12 months, the change of stoma diameter was positively...... associated with the change of solid foods consumed (by weight, p = 0.01; by energy content, p = 0.02). The change of pouch volume was negatively associated with the change of energy from beverages (p = 0.005). In conclusion, it seems impossible to tailor the reduction of food intake through adjustments...

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

    NARCIS (Netherlands)

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

    2009-01-01

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

  19. The influence of scan mode and circle fitting on tree stem detection, stem diameter and volume extraction from terrestrial laser scans

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    Pueschel, Pyare; Newnham, Glenn; Rock, Gilles; Udelhoven, Thomas; Werner, Willy; Hill, Joachim

    2013-03-01

    Terrestrial laser scanning (TLS) has been used to estimate a number of biophysical and structural vegetation parameters. Of these stem diameter is a primary input to traditional forest inventory. While many experimental studies have confirmed the potential for TLS to successfully extract stem diameter, the estimation accuracies differ strongly for these studies - due to differences in experimental design, data processing and test plot characteristics. In order to provide consistency and maximize estimation accuracy, a systematic study into the impact of these variables is required. To contribute to such an approach, 12 scans were acquired with a FARO photon 120 at two test plots (Beech, Douglas fir) to assess the effects of scan mode and circle fitting on the extraction of stem diameter and volume. An automated tree stem detection algorithm based on the range images of single scans was developed and applied to the data. Extraction of stem diameter was achieved by slicing the point cloud and fitting circles to the slices using three different algorithms (Lemen, Pratt and Taubin), resulting in diameter profiles for each detected tree. Diameter at breast height (DBH) was determined using both the single value for the diameter fitted at the nominal breast height and by a linear fit of the stem diameter vertical profile. The latter is intended to reduce the influence of outliers and errors in the ground level determination. TLS-extracted DBH was compared to tape-measured DBH. Results show that tree stems with an unobstructed view to the scanner can be successfully extracted automatically from range images of the TLS data with detection rates of 94% for Beech and 96% for Douglas fir. If occlusion of trees is accounted for stem detection rates decrease to 85% (Beech) and 84% (Douglas fir). As far as the DBH estimation is concerned, both DBH extraction methods yield estimates which agree with reference measurements, however, the linear fit based approach proved to be more

  20. Kidney volume correlates with tumor diameter in renal cell carcinoma and is associated with histological poor prognostic features.

    Science.gov (United States)

    Hayes, Brian D; Finn, Stephen P

    2014-02-01

    We aimed to correlate kidney volume (KV) in renal cell carcinoma nephrectomy specimens with tumor diameter (TD), macroscopic growth pattern, and histological features associated with poor prognosis. Histopathology reports, macroscopic specimen photographs, and selected glass slides were retrospectively reviewed. KV was approximated to the volume of an ellipsoid. A total of 273 specimens were identified with median KV 245 cm(3). Kidneys larger than this contained larger tumors (7.5 vs 4.5 cm). KV was significantly greater in tumors of high grade, involving perinephric fat, exhibiting venous invasion, and involving renal sinus. There was a robust linear correlation between KV and TD (r = 0.602) and a weaker correlation between kidney diameter (KD) and TD (r = 0.53). In pT1 tumors, KV (r = 0.40) also correlated better with TD than did KD (r = 0.27). By multiple regression analysis, both TD and venous invasion independently predicted both KD (R (2) = 38.27%) and KV (R (2) = 51.97%). KV and KD correlate well with TD and histopathological features of aggressiveness, although KD correlates better overall and in the pT1 subset.

  1. Role of BK channels in the apoptotic volume decrease in native eel intestinal cells

    DEFF Research Database (Denmark)

    Lionetto, Maria Giulia; Giordano, Maria Elena; Calisi, Antonio

    2010-01-01

    of these channels in the Apoptotic Volume Decrease (AVD) of isolated eel enterocytes, and the possible interaction between BK channels and the progression of apoptosis. The detection of apoptosis was performed by confocal microscopy and annexin V and propidium iodide labelling; cell volume changes were monitored...

  2. KCNQ channels are involved in the regulatory volume decrease response in primary neonatal rat cardiomyocytes

    DEFF Research Database (Denmark)

    Calloe, Kirstine; Nielsen, Morten Schak; Grunnet, Morten;

    2007-01-01

    Cardiomyocytes may experience significant cell swelling during ischemia and reperfusion. Such changes in cardiomyocyte volume have been shown to affect the electrical properties of the heart, possibly leading to cardiac arrhythmia. In the present study the regulatory volume decrease (RVD) response...

  3. Inhibition of Regulatory Volume Decrease Enhances the Cytocidal Effect of Hypotonic Shock in Hepatocellular Carcinoma.

    Science.gov (United States)

    Kudou, Michihiro; Shiozaki, Atsushi; Kosuga, Toshiyuki; Ichikawa, Daisuke; Konishi, Hirotaka; Morimura, Ryo; Komatsu, Shuhei; Ikoma, Hisashi; Fujiwara, Hitoshi; Okamoto, Kazuma; Hosogi, Shigekuni; Nakahari, Takashi; Marunaka, Yoshinori; Otsuji, Eigo

    2016-01-01

    Background : Hypotonic shock induces cytocidal effects through cell rupture, and cancer therapy based on this mechanism has been clinically administered to hepatocellular carcinoma patients. We herein investigated the effectiveness of hypotonic shock combined with the inhibition of regulatory volume decrease as cancer therapy for hepatocellular carcinoma. Methods : Morphological changes in human hepatocellular carcinoma cell lines were observed under a differential interference contrast microscope connected to a high-speed digital video camera. Cell volume changes under hypotonic shock with or without chloride, potassium, or water channel blockers were observed using a high-resolution flow cytometer. In order to investigate cytocidal effects, the number of surviving cells was compared after exposure to hypotonic solution with and without each channel blocker (re-incubation experiment). Results : Video recordings showed that cells exposed to distilled water rapidly swelled and then ruptured. Cell volume measurements revealed regulatory volume decrease under mild hypotonic shock, whereas severe hypotonic shock increased the number of broken fragments as a result of cell rupture. Moreover, regulatory volume decrease was inhibited in cells treated with each channel blocker. Re-incubation experiments showed the cytocidal effects of hypotonic shock in cells exposed to hypotonic solution, and additional treatments with each channel blocker enhanced these effects. Conclusion : The inhibition of regulatory volume decrease with chloride, potassium, or water channel blockers may enhance the cytocidal effects of hypotonic shock in hepatocellular carcinoma. Hypotonic shock combined with the inhibition of regulatory volume decrease was a more effective therapy than hypotonic shock alone.

  4. EstimatingPinus palustris tree diameter and stem volume from tree height, crown area and stand-level parameters

    Institute of Scientific and Technical Information of China (English)

    C.A. Gonzalez-Benecke; Salvador A. Gezan; Lisa J. Samuelson; Wendell P. Cropper Jr.; Daniel J. Leduc; Timothy A. Martin

    2014-01-01

    Accurate and efficient estimation of forest growth and live biomass is a critical element in assessing potential responses to forest management and environmental change. The objective of this study was to develop models to predict longleaf pine tree diameter at breast height (dbh) and merchantable stem volume (V) using data obtained from field measurements. We used longleaf pine tree data from 3,376 planted trees on 127 permanent plots located in the U.S. Gulf Coastal Plain region to fit equations to predict dbh and V as functions of tree height (H) and crown area (CA). Prediction of dbh as a function of H improved when CA was added as an additional independent variable. Similarly, predic-tions of V based on H improved when CA was included. Incorporation of additional stand variables such as age, site index, dominant height, and stand density were also evaluated but resulted in only small improve-ments in model performance. For model testing we used data from planted and naturally-regenerated trees located inside and outside the geographic area used for model fitting. Our results suggest that the models are a robust alternative for dbh and V estimations when H and CA are known on planted stands with potential for naturally-regenerated stands, across a wide range of ages. We discuss the importance of these models for use with metrics derived from remote sensing data.

  5. Decreased blood platelet volume and count in patients with liver disease

    DEFF Research Database (Denmark)

    Jørgensen, B; Fischer, E; Ingeberg, S;

    1984-01-01

    Mean platelet volume (MPV) and count (PLT) were assessed in patients with moderately affected liver function. PLT was significantly decreased in patients with liver disease (197 X 10(9)l-1 +/- 87 (SD), no. = 79) compared with that of controls (273 X 10(9)l-1 +/- 53 (SD), no. = 37, P less than 0...

  6. Lumber volume and value recovery from small-diameter black cherry, sugar maple, and red oak logs

    Science.gov (United States)

    Jan Wiedenbeck; Matthew Scholl; Paul Blankenhorn; Chuck. Ray

    2017-01-01

    While only a very small percentage of hardwood logs sawn by conventional sawmills in the U.S. have small-end diameters less than 10 in, portable and scragg mills often saw smaller logs. With the closure of regionally important oriented strand board and pulpwood operations, small-diameter logs are considered to have no value in some markets. This study was...

  7. Regulatory Volume Decrease in Neural Precursor Cells: Taurine Efflux and Gene Microarray Analysis

    Directory of Open Access Journals (Sweden)

    Reyna Hernández-Benítez

    2014-11-01

    Full Text Available Background/Aims: Neural stem/ progenitor cells (NPCs endure important changes in cell volume during growth, proliferation and migration. As a first approach to know about NPC response to cell volume changes, the Regulatory Volume Decrease (RVD subsequent to hypotonic swelling was investigated. Methods: NPCs obtained from the mesencephalon and the subventricular zone of embryonic and adult mice, respectively, were grown and cultured as neurospheres. Cell volume changes were measured by large-angle light-scattering and taurine efflux by [3H]-taurine. Expression of genes encoding molecules related to RVD was analysed using a DNA microarray obtained from NPC samples. Results: Embryonic and adult NPCs exposed to osmolarity reduction (H15, H30, H40 exhibited rapid swelling followed by RVD. The magnitude, efficiency and pharmacological profile, of RVD and of [3H]-taurine osmosensitive efflux were comparable to those found in cultured brain cells, astrocytes and neurons. The relative expression of genes encoding molecules related to volume regulation, i.e. K+ and Cl- channels, cotransporters, exchangers and aquaporins were identified in NPCs. Conclusion: NPCs show the ability to respond to hypotonic-evoked volume changes by adaptative recovery processes, similar to those found in other cultured brain cells. Genes related to molecules involved in RVD were found expressed in NPCs.

  8. Decrease in shunt volume in patients with cryptogenic stroke and patent foramen ovale

    Directory of Open Access Journals (Sweden)

    Pabst Wolfgang

    2010-12-01

    Full Text Available Abstract Background In patients with patent foramen ovale (PFO there is evidence supporting the hypothesis of a change in right-to-left shunt (RLS over time. Proven, this could have implications for the care of patients with PFO and a history of stroke. The following study addressed this hypothesis in a cohort of patients with stroke and PFO. Methods The RLS volume assessed during hospitalisation for stroke (index event/T0 was compared with the RLS volume on follow-up (T1 (median time between T0 and T1 was 10 months. In 102 patients with a history of stroke and PFO the RLS volume was re-assessed on follow-up using contrast-enhanced transcranial Doppler/duplex (ce-TCD ultrasound. A change in RLS volume was defined as a difference of ≥20 microembolic signals (MES or no evidence of RLS during ce-TCD ultrasound on follow-up. Results There was evidence of a marked reduction in RLS volume in 31/102 patients; in 14/31 patients a PFO was no longer detectable. An index event classified as cryptogenic stroke (P Conclusions RLS volume across a PFO decreases over time, especially in patients with cryptogenic stroke. These may determine the development of new strategies for the management in the secondary stroke prevention.

  9. Axon diameter and intra-axonal volume fraction of the corticospinal tract in idiopathic normal pressure hydrocephalus measured by q-space imaging.

    Directory of Open Access Journals (Sweden)

    Kouhei Kamiya

    Full Text Available PURPOSE: Previous studies suggest that compression and stretching of the corticospinal tract (CST potentially cause treatable gait disturbance in patients with idiopathic normal pressure hydrocephalus (iNPH. Measurement of axon diameter with diffusion MRI has recently been used to investigate microstructural alterations in neurological diseases. In this study, we investigated alterations in the axon diameter and intra-axonal fraction of the CST in iNPH by q-space imaging (QSI analysis. METHODS: Nineteen patients with iNPH and 10 age-matched controls were recruited. QSI data were obtained with a 3-T system by using a single-shot echo planar imaging sequence with the diffusion gradient applied parallel to the antero-posterior axis. By using a two-component low-q fit model, the root mean square displacements of intra-axonal space ( =  axon diameter and intra-axonal volume fraction of the CST were calculated at the levels of the internal capsule and body of the lateral ventricle, respectively. RESULTS: Wilcoxon's rank-sum test revealed a significant increase in CST intra-axonal volume fraction at the paraventricular level in patients (p<0.001, whereas no significant difference was observed in the axon diameter. At the level of the internal capsule, neither axon diameter nor intra-axonal volume fraction differed significantly between the two groups. CONCLUSION: Our results suggest that in patients with iNPH, the CST does not undergo irreversible axonal damage but is rather compressed and/or stretched owing to pressure from the enlarged ventricle. These analyses of axon diameter and intra-axonal fraction yield insights into microstructural alterations of the CST in iNPH.

  10. Decreased left temporal lobe volume of panic patients measured by magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, R.R.; Del-Ben, C.M.; Araujo, D.; Crippa, J.A.; Graeff, F.G. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Dept. de Neurologia e Psicologia Medica]. E-mail: fgraeff@keynet.com.br; Santos, A.C. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Dept. de Clinica Medica; Guimaraes, F.S. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Dept. de Farmacologia

    2003-07-01

    Reported neuroimaging studies have shown functional and morphological changes of temporal lobe structures in panic patients, but only one used a volumetric method. The aim of the present study was to determine the volume of temporal lobe structures in patients with panic disorder, measured by magnetic resonance imaging. Eleven panic patients and eleven controls matched for age, sex, handedness, socioeconomic status and years of education participated in the study. The mean volume of the left temporal lobe of panic patients was 9% smaller than that of controls (t{sub 21} = 2.37, P = 0.028). In addition, there was a trend (P values between 0.05 and 0.10) to smaller volumes of the right temporal lobe (7%, t{sub 21} = 1.99, P = 0.06), right amygdala (8%, t{sub 21} = 1.83, P = 0.08), left amygdala (5%, t{sub 21} = 1.78, P 0.09) and left hippocampus (9%, t{sub 21} = 1.93, P = 0.07) in panic patients compared to controls. There was a positive correlation between left hippocampal volume and duration of panic disorder (r = 0.67, P = 0.025), with recent cases showing more reduction than older cases. The present results show that panic patients have a decreased volume of the left temporal lobe and indicate the presence of volumetric abnormalities of temporal lobe structures. (author)

  11. Early Fluid Resuscitation and High Volume Hemofiltration Decrease Septic Shock Progression in Swine.

    Science.gov (United States)

    Zhao, Ping; Zheng, Ruiqiang; Xue, Lu; Zhang, Min; Wu, Xiaoyan

    2015-01-01

    This study aimed to assess the effects of early fluid resuscitation (EFR) combined with high volume hemofiltration (HVHF) on the cardiopulmonary function and removal of inflammatory mediators in a septic shock swine model. Eighteen swine were randomized into three groups: control (n = 6) (extracorporeal circulating blood only), continuous renal replacement therapy (CRRT) (n = 6; ultrafiltration volume = 25 mL/Kg/h), and HVHF (n = 6; ultrafiltration volume = 85 mL/Kg/h). The septic shock model was established by intravenous infusion of lipopolysaccharides (50 µg/kg/h). Hemodynamic parameters (arterial pressure, heart rate, cardiac output, stroke volume variability, left ventricular contractility, systemic vascular resistance, and central venous pressure), vasoactive drug parameters (dose and time of norepinephrine and hourly fluid intake), pulmonary function (partial oxygen pressure and vascular permeability), and cytokines (interleukin-6 and interleukin-10) were observed. Treatment resulted in significant changes at 4-6 h. HVHF was beneficial, as shown by the dose of vasoactive drugs, fluid intake volume, left ventricular contractility index, and partial oxygen pressure. Both CRRT and HVHF groups showed improved removal of inflammatory mediators compared with controls. In conclusion, EFR combined with HVHF improved septic shock in this swine model. The combination decreased shock progression, reduced the need for vasoactive drugs, and alleviated the damage to cardiopulmonary functions.

  12. Long-term results of preventive embolization of renal angiomyolipomas: evaluation of predictive factors of volume decrease

    Energy Technology Data Exchange (ETDEWEB)

    Hocquelet, A.; Cornelis, F.; Le Bras, Y.; Meyer, M.; Tricaud, E.; Lasserre, A.S.; Grenier, N. [Centre Hospitalier Universitaire Pellegrin, Diagnostic and Therapeutic Urology and Vascular Imaging, Bordeaux (France); Ferriere, J.M.; Robert, G. [Centre Hospitalier Universitaire Pellegrin, Urology Service, Bordeaux (France)

    2014-08-15

    To evaluate the efficacy of selective arterial embolization (SAE) of angiomyolipomas based on the percentage volume reduction after embolization and to identify predictive factors of volume decrease. Patients receiving prophylactic SAE of renal angiomyolipomas were included retrospectively over 3 years. The volume change after SAE and haemorrhagic or surgical events were recorded. Initial tumour volume, percentage tumour fat content, mean tumour density, embolic agent used, number of angiomyolipomas and tuberous sclerosis disease were evaluated as predictive factors of volume decrease. A total of 19 patients with 39 angiomyolipomas were included with median follow-up of 28 months (interquartile range 21-37 months). All treatments were technically successful (92 % primary and 8 % secondary). No distal bleeding or any increase in size or surgical nephrectomy after SAE was recorded. Mean volume reduction was 72 % (±24 %). Volumes before SAE (R{sup 2} = 0.276; p = 0.001), percentage fat content (R{sup 2} = 0.612; p < 0.0001) and mean angiomyolipoma density (R{sup 2} = 0.536; p < 0.0001) were identified as predictive factors of volume decrease. In multivariate regression, only percentage fat content influenced volume decreases. SAE is an efficient treatment for angiomyolipoma devascularisation and volume reduction. A significant reduction of volume is modulated by the initial volume and tissue composition of the tumour. (orig.)

  13. Regulatory volume decrease in cardiomyocytes is modulated by calcium influx and reactive oxygen species.

    Science.gov (United States)

    Rojas-Rivera, Diego; Díaz-Elizondo, Jessica; Parra, Valentina; Salas, Daniela; Contreras, Ariel; Toro, Barbra; Chiong, Mario; Olea-Azar, Claudio; Lavandero, Sergio

    2009-11-01

    We investigated the role of Ca(2+) in generating reactive oxygen species (ROS) induced by hyposmotic stress (Hypo) and its relationship to regulatory volume decrease (RVD) in cardiomyocytes. Hypo-induced increases in cytoplasmic and mitochondrial Ca(2+). Nifedipine (Nife) inhibited both Hypo-induced Ca(2+) and ROS increases. Overexpression of catalase (CAT) induced RVD and a decrease in Hypo-induced blebs. Nife prevented CAT-dependent RVD activation. These results show a dual role of Hypo-induced Ca(2+) influx in the control of cardiomyocyte viability. Hypo-induced an intracellular Ca(2+) increase which activated RVD and inhibited necrotic blebbing thus favoring cell survival, while simultaneously increasing ROS generation, which in turn inhibited RVD and induced necrosis.

  14. Sleep apnea termination decreases cerebral blood volume: a near-infrared spectroscopy case study

    Science.gov (United States)

    Virtanen, Jaakko; Noponen, Tommi; Salmi, Tapani; Toppila, Jussi; Meriläinen, Pekka

    2009-07-01

    Medical near-infrared spectroscopy (NIRS) can be used to estimate cerebral haemodynamic changes non-invasively. Sleep apnea is a common sleep disorder where repetitive pauses in breathing decrease the quality of sleep and exposes the individual to various health problems. We have measured oxygenated and deoxygenated haemoglobin concentration changes during apneic events in sleep from the forehead of one subject using NIRS and used principal component analysis to extract extracerebral and cortical haemodynamic changes from NIRS signals. Comparison of NIRS signals with EEG, bioimpedance, and pulse oximetry data suggests that termination of apnea leads to decreases in cerebral blood volume and flow that may be related to neurological arousal via neurovascular coupling.

  15. Increased CSF-BACE1 activity associated with decreased hippocampus volume in Alzheimer's disease.

    LENUS (Irish Health Repository)

    Ewers, Michael

    2012-02-01

    The enzyme beta-secretase (BACE1) is essentially involved in the production of cerebral amyloidogenic pathology in Alzheimer\\'s disease (AD). The measurement of BACE1 activity in cerebrospinal fluid (CSF) has been reported, which may render CSF measurement of BACE1 a potential biomarker candidate of AD. In order to investigate whether BACE1 protein activity is correlated with regional brain atrophy in AD, we investigated the association between CSF levels of BACE1 and MRI-assessed hippocampus volume in patients with AD (n = 30). An increase in CSF-BACE1 activity was associated with decreased left and right hippocampus volume corrected for global head volume in the AD patients. Boot-strapped regression analysis showed that increased CSF levels of BACE1 activity were associated with increased CSF concentration of total tau but not amyloid-beta1-42 in AD. White matter hyperintensities did not influence the results. BACE1 activity and protein levels were significantly increased in AD compared to 19 elderly healthy controls. Thus, the CSF biomarker candidate of BACE1 activity was associated with hippocampus atrophy in AD in a robust manner and may reflect neurotoxic amyloid-beta-related processes.

  16. Alcohol exposure in utero is associated with decreased gray matter volume in neonates.

    Science.gov (United States)

    Donald, Kirsten A; Fouche, J P; Roos, Annerine; Koen, Nastassja; Howells, Fleur M; Riley, Edward P; Woods, Roger P; Zar, Heather J; Narr, Katherine L; Stein, Dan J

    2016-02-01

    Neuroimaging studies have indicated that prenatal alcohol exposure is associated with alterations in the structure of specific brain regions. However, the temporal specificity of such changes and their behavioral consequences are less known. Here we explore the brain structure of infants with in utero exposure to alcohol shortly after birth. T2 structural MRI images were acquired from 28 alcohol-exposed infants and 45 demographically matched healthy controls at 2-4 weeks of age on a 3T Siemens Allegra system as part of large birth cohort study, the Drakenstein Child Health Study (DCHS). Neonatal neurobehavior was assessed at this visit; early developmental outcome assessed on the Bayley Scales of Infant Development III at 6 months of age. Volumes of gray matter regions were estimated based on the segmentations of the University of North Carolina neonatal atlas. Significantly decreased total gray matter volume was demonstrated for the alcohol-exposed cohort compared to healthy control infants (p smoking status. Both early neurobehavioral and developmental adverse outcomes at 6 months across multiple domains were significantly associated with regional volumes primarily in the temporal and frontal lobes in infants with prenatal alcohol exposure. Alcohol exposure during the prenatal period has potentially enduring neurobiological consequences for exposed children. These findings suggest the effects of prenatal alcohol exposure on brain growth is present very early in the first year of life, a period during which the most rapid growth and maturation occurs.

  17. Anorexia Nervosa during Adolescence Is Associated with Decreased Gray Matter Volume in the Inferior Frontal Gyrus.

    Directory of Open Access Journals (Sweden)

    Takashi X Fujisawa

    Full Text Available Anorexia nervosa (AN is an eating disorder characterized by the relentless pursuit to lose weight, mostly through self-starvation, and a distorted body image. AN tends to begin during adolescence among women. However, the underlying neural mechanisms related to AN remain unclear. Using voxel-based morphometry based on magnetic resonance imaging scans, we investigated whether the presence of AN was associated with discernible changes in brain morphology. Participants were 20 un-medicated, right-handed patients with early-onset AN and 14 healthy control subjects. Group differences in gray matter volume (GMV were assessed using high-resolution, T1-weighted, volumetric magnetic resonance imaging datasets (3T Trio scanner; Siemens AG and analyzed after controlling for age and total GMV, which was decreased in the bilateral inferior frontal gyrus (IFG (left IFG: FWE corrected, p < 0.05; right IFG: uncorrected, p < 0.05 of patients with AN. The GMV in the bilateral IFG correlated significantly with current age (left IFG: r = -.481, p < .05; right IFG: r = -.601, p < .01 and was limited to the AN group. We speculate that decreased IFG volume might lead to deficits in executive functioning or inhibitory control within neural reward systems. Precocious or unbalanced neurological trimming within this particular region might be an important factor for the pathogenesis of AN onset.

  18. Moderate intensity supine exercise causes decreased cardiac volumes and increased outer volume variations: a cardiovascular magnetic resonance study

    DEFF Research Database (Denmark)

    Steding-Ehrenborg, Katarina; Jablonowski, Robert; Arvidsson, Per M;

    2013-01-01

    The effects on left and right ventricular (LV, RV) volumes during physical exercise remains controversial. Furthermore, no previous study has investigated the effects of exercise on longitudinal contribution to stroke volume (SV) and the outer volume variation of the heart. The aim of this study...

  19. Study on Ground Diameter Single Entry Volume Table of Cunninghamia lanceolataPlantation%杉木人工林地径材积表编制方法研究

    Institute of Scientific and Technical Information of China (English)

    苏杰南; 黎良财

    2011-01-01

    Based on the determination of the DBH (D13), ground diameter (D0.1). Height (H) and volume (V) of Cunning-hamia lanceolcta (Lamb.) Hook, artifical forests, the single ground diameter volume table was prepared and compared using multiple model selection V-Da1 and double volume table. The test of the two equation showed that they reached the accuracy requirements in production, therefore could be applied in forest survey and management.%根据杉木[ Cunninghamia lanceolata (Lamb.) Hook.]人工林样木的胸径D1.3地径D0.1、树高H的测定值和立木材积的计算值V,分别采用材积V-地径D0.1多模型选优法和二元材积表导算法编制一元地径材积表,并进行比较.经检验,这两种方法编制的数表均能够满足生产上的精度要求,可以作为林业调查、经营管理的工具数表.

  20. A Fundamental Limitation of Small Diameter Single-Walled Carbon Nanotube Synthesis—A Scaling Rule of the Carbon Nanotube Yield with Catalyst Volume

    Directory of Open Access Journals (Sweden)

    Kenji Hata

    2013-07-01

    Full Text Available Understanding the fundamental mechanisms and limiting processes of the growth of single-walled carbon nanotube (SWCNT would serve as a guide to achieve further control on structural parameters of SWCNT. In this paper, we have studied the growth kinetics of a series of SWCNT forests continuously spanning a wide range of diameters (1.9–3.2 nm, and have revealed an additional fundamental growth limiting process where the mass of the individual SWCNT is determined by the individual catalyst volume. Calculation of the conversion rate of carbon atoms into CNTs per Fe atom is 2 × 102 atoms per second. This rate limiting process provides an important understanding where the larger diameter SWCNT would grow faster, and thus be more suited for mass production.

  1. Regulatory volume decrease in isolated nematocytes is affected by crude venom from the jellyfish Pelagia noctiluca

    Directory of Open Access Journals (Sweden)

    Rossana Morabito

    2014-11-01

    Full Text Available Crude venom from nematocysts of the Scyphozoan Pelagia noctiluca possesses hemolytic and cytotoxic power on cultured cells and elicits local and systemic inflammation reactions in vivo. The ability of regulating their volume after exposure to an anisosmotic solution is a fundamental feature common to cells from vertebrates and invertebrates, including Cnidarians. The aim of the present work i s to assay whether crude venom from Pelagia noctiluca may affect the regulatory volume decrease (RVD of nematocytes isolated from the Anthozoan Aiptasia mutabilis, here employed as a cell model. For this purpose, nematocytes were isolated by 605 mM NaSCN plus 0.01 mM Ca2+ application on acontia of Aiptasia mutabilis, while crude venom was obtained by sonication of a population of, respectively, 10, 25 and 50 nematocysts/µL (n/µL. Isolated nematocytes were pre-treated for 30 min with crude venom, submitted to hypotonic stress and their osmotic response and RVD were measured optically. Our results show that, after exposure to crude venom, nematocytes were morphologically intact, as shown by the Trypan blue exclusion test, but did not exhibit RVD. This effect was dose-dependent and reversed by the ionopho re gramicidin. The last observation suggests an inhibitory effect of venom on cell membrane ion transport mechanisms involved in RVD. Further studies are needed to verify this hypothesis and ascertain if a similar effect could be observed in human cells.

  2. Induction of apoptosis by nitric oxide in macrophages is independent of apoptotic volume decrease.

    Science.gov (United States)

    Hortelano, S; Zeini, M; Castrillo, A; Alvarez, A M; Boscá, L

    2002-06-01

    Apoptosis occurs through a sequence of specific biochemical and morphological alterations that define the progress of cell death. The changes of the mitochondrial inner membrane potential (DeltaPsi(m)), the release of cytochrome c to the cytosol, the apoptotic volume decrease (AVD) and the activation of caspases have been measured in RAW 264.7, HeLa and Jurkat T cells incubated with molecules that induce apoptosis through the mitochondrial pathway. Our data show that NO, staurosporine, etoposide and camptothecin increased DeltaPsi(m) in macrophages but not in HeLa and Jurkat cells, that exhibited a DeltaPsi(m) decrease. Moreover, the apoptosis induced by NO in macrophages, but not that promoted by staurosporine, might occur in the absence of AVD. Analysis of the sequence of apoptotic manifestations shows that DeltaPsi(m) precedes AVD and caspase activation in RAW 264.7 cells. Inhibition of AVD abrogates apoptosis in HeLa and Jurkat T cells regardless of the stimuli used. These data suggest that the changes of DeltaPsi(m) are cell-type dependent and that AVD is dispensable for apoptosis in macrophages.

  3. Mean platelet volume is decreased in adults with active lupus disease

    Directory of Open Access Journals (Sweden)

    Guillermo Delgado-García

    Full Text Available ABSTRACT Background: Only a few biomarkers are available for assessing disease activity in systemic lupus erythematosus (SLE. Mean platelet volume (MPV has been recently studied as an inflammatory biomarker. It is currently unclear whether MPV may also play a role as a biomarker of disease activity in adult patients with SLE. Objective: We investigated the association between MPV and disease activity in adult patients with SLE. Methods: In this retrospective study, we compared two groups of adult patients divided according to disease activity (36 per group. Subjects were age- and gender-matched. Results: MPV was significantly decreased with respect to those of inactive patients (7.16 ± 1.39 vs. 8.16 ± 1.50, p = 0.005. At a cutoff level of 8.32 fL, MPV has a sensitivity of 86% and a specificity of 41% for the detection of disease activity. A modest positive correlation was found between MPV and albumin (r = 0.407, p = 0.001, which in turn is inversely associated with disease activity. Conclusions: In summary, MPV is decreased in adult patients with active lupus disease, and positively correlated with albumin, another biomarker of disease activity. Prospective studies are needed to evaluate the prognostic value of this biomarker.

  4. Colloid volume loading does not mitigate decreases in central blood volume during simulated hemorrhage while heat stressed

    DEFF Research Database (Denmark)

    Crandall, Craig G; Wilson, Thad E; Marving, Jens

    2012-01-01

    Heat stress results in profound reductions in the capacity to withstand a simulated hemorrhagic challenge; however, this capacity is normalized if the individual is volume loaded prior to the challenge. The present study tested the hypothesis that volume loading during passive heat stress attenua...

  5. Is the inferior vena cava diameter measured by bedside ultrasonography valuable in estimating the intravascular volume in patients with septic shock?

    Directory of Open Access Journals (Sweden)

    Mortaza Talebi Doluie

    2016-07-01

    Full Text Available Introduction:Resuscitation should be initiated immediately in shock. Early goal-directed therapy is an established algorithm for the resuscitation in septic shock. The first step is to maintain cardiac preload. Central venous pressure (CVP plays an important role in goal-directed therapy. Central venous catheterization is invasive and time-consuming in emergency conditions. There are some alternative and noninvasive methods for estimating the intravascular volume such as measuring the inferior vena cava (IVC diameter by ultrasonography. Methods: We searched PubMed, Google scholar, and Scopus databases with keywords (central venous pressure OR venous pressure OR CVP AND (ultrasonography OR sonography AND (sepsis OR septic shock AND (inferior vena cava OR IVC.Result: The search resulted in 2550 articles. The articles were appraised regarding the relevance, type of article, and statistical methods. Finally, 12 articles were selected. The number of patients was between 30 and 83 cases (mean age=57-67 years, intubated and non-intubated in each study. The IVC diameter was measured in respiratory cycle by bedside ultrasonography in longitudinal subxiphoid view and caval index was calculated, then they were compared with the CVP measured by central venous catheter.Discussion: CVP is an indicator of intravascular fluid status and right heart function. CVP measurement is an invasive method and of course with some complications. The IVC is the biggest vein of venous system with low-pressure; expansion of the vein reflects intravascular volume.Conclusion: It seems that IVC diameter measured by ultrasonography could be used as an alternative method for the determination of CVP in the emergency or critical patients.

  6. Fused silica capillaries with two segments of different internal diameters and inner surface roughnesses prepared by etching with supercritical water and used for volume coupling electrophoresis.

    Science.gov (United States)

    Horká, Marie; Karásek, Pavel; Roth, Michal; Šlais, Karel

    2017-02-22

    In this work, single-piece fused silica capillaries with two different internal diameter segments featuring different inner surface roughness were prepared by new etching technology with supercritical water and used for volume coupling electrophoresis. The concept of separation and online pre-concentration of analytes in high conductivity matrix is based on the online large-volume sample pre-concentration by the combination of transient isotachophoretic stacking and sweeping of charged proteins in micellar electrokinetic chromatography using non-ionogenic surfactant. The modified surface roughness step helped to the significant narrowing of the zones of examined analytes. The sweeping and separating steps were accomplished simultaneously by the use of phosphate buffer (pH 7) containing ethanol, non-ionogenic surfactant Brij 35, and polyethylene glycol (PEG 10000) after sample injection. Sample solution of a large volume (maximum 3.7 μL) dissolved in physiological saline solution was injected into the wider end of capillary with inlet inner diameter from 150, 185 or 218 μm. The calibration plots were linear (R(2) ∼ 0.9993) over a 0.060-1 μg/mL range for the proteins used, albumin and cytochrome c. The peak area RSDs from at least 20 independent measuremens were below 3.2%. This online pre-concentration technique produced a more than 196-fold increase in sensitivity, and it can be applied for detection of, e.g. the presence of albumin in urine (0.060 μg/mL).

  7. Regulatory volume decrease in Leishmania mexicana: effect of anti-microtubule drugs

    Directory of Open Access Journals (Sweden)

    Francehuli Dagger

    2013-02-01

    Full Text Available The trypanosomatid cytoskeleton is responsible for the parasite's shape and it is modulated throughout the different stages of the parasite's life cycle. When parasites are exposed to media with reduced osmolarity, they initially swell, but subsequently undergo compensatory shrinking referred to as regulatory volume decrease (RVD. We studied the effects of anti-microtubule (Mt drugs on the proliferation of Leishmania mexicana promastigotes and their capacity to undergo RVD. All of the drugs tested exerted antiproliferative effects of varying magnitudes [ansamitocin P3 (AP3> trifluoperazine > taxol > rhizoxin > chlorpromazine]. No direct relationship was found between antiproliferative drug treatment and RVD. Similarly, Mt stability was not affected by drug treatment. Ansamitocin P3, which is effective at nanomolar concentrations, blocked amastigote-promastigote differentiation and was the only drug that impeded RVD, as measured by light dispersion. AP3 induced 2 kinetoplasts (Kt 1 nucleus cells that had numerous flagella-associated Kts throughout the cell. These results suggest that the dramatic morphological changes induced by AP3 alter the spatial organisation and directionality of the Mts that are necessary for the parasite's hypotonic stress-induced shape change, as well as its recovery.

  8. Involvement of regulatory volume decrease in the migration of nasopharyngeal carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    Jian Wen MAO; Li Xin CHEN; Li Wei WANG; Tim JACOB; Xue Rong SUN; Hui LI; Lin Yan ZHU; Pan LI; Ping ZHONG; Si Huai NIE

    2005-01-01

    The transwell chamber migration assay and CCD digital camera imaging techniques were used to investigate the relationship between regulatory volume decrease (RVD) and cell migration in nasopharyngeal carcinoma cells (CNE-2Z cells). Both migrated and non-migrated CNE-2Z cells, when swollen by 47% hypotonic solution, exhibited RVD which was inhibited by extracellular application of chloride channel blockers adenosine 5'-triphosphate (ATP), 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) and tamoxifen. However, RVD rate in migrated CNE-2Z cells was bigger than that of non-migrated cells and the sensitivity of migrated cells to NPPB and tamoxifen was higher than that of nonmigrated cells. ATP, NPPB and tamoxifen also inhibited migration of CNE-2Z cells. The inhibition of migration was positively correlated to the blockage of RVD, with a correlation coefficient (r) = 0.99, suggesting a functional relationship between RVD and cell migration. We conclude that RVD is involved in cell migration and RVD may play an important role in migratory process in CNE-2Z cells.

  9. Liver volume, as assessed by four ultrasonic crystals arranged to form a tetrahedron, decreases during anaphylactic shock in anesthetized rats.

    Science.gov (United States)

    Takano, Hiromichi; Shibamoto, Toshishige; Zhang, Wei; Kurata, Yasutaka

    2010-12-01

    We determined the hepatic volume change in anaphylactic hypotension by using four ultrasonic crystals in anesthetized rats. The hepatic volume was measured with four ultrasonic crystals arranged to form a tetrahedron on the liver surface. Before in vivo experiments, using isolated perfused rat liver preparations, we compared the measured liver volume changes with the whole-liver weight changes during hepatic blood flow rate changes and venoconstriction induced by norepinephrine. The measured relative change of the tetrahedron volume (V[utc]; percentage changes of the initial volume) was closely correlated with the liver weight change (W; percentage changes of the initial liver weight): V(utc) = 0.85W - 4.11 (r² = 0.67). Then, we measured the liver weight and the tetrahedron volume during hepatic anaphylaxis in isolated perfused liver excised from the rats sensitized with ovalbumin. An injection of the antigen into the perfusate caused anaphylactic venoconstriction, liver weight loss (1.1 ± 0.3 g; 9% ± 1%), and the tetrahedron volume reduction (12% ± 4%). Finally, we measured the liver volume change during anaphylactic hypotension in anesthetized ovalbumin-sensitized rats. When the antigen was i.v. injected into anesthetized rats, along with systemic hypotension and hepatic venoconstriction, the liver tetrahedron volume decreased by 6% ± 2% from baseline. In conclusion, we established a method to measure the hepatic volume by using four ultrasonic crystals forming a tetrahedron. Using this ultrasonic crystal method, we demonstrated that liver volume decreases during anaphylactic hypotension in anesthetized rats.

  10. The decrease of cardiac chamber volumes and output during positive-pressure ventilation

    DEFF Research Database (Denmark)

    Kristensen, Kasper Kyhl; Ahtarovski, Kiril Aleksov; Iversen, Kasper

    2013-01-01

    the effect of PPV on the central circulation by studying cardiac chamber volumes with cardiac magnetic resonance imaging (CMR). We hypothesized that PPV lowers cardiac output (CO) mainly via the Frank-Starling relationship. In 18 healthy volunteers, cardiac chamber volumes and flow in aorta and the pulmonary...

  11. Spider phobia is associated with decreased left amygdala volume: a cross-sectional study

    Science.gov (United States)

    2013-01-01

    Background Evidence from animal and human studies imply the amygdala as the most critical structure involved in processing of fear-relevant stimuli. In phobias, the amygdala seems to play a crucial role in the pathogenesis and maintenance of the disorder. However, the neuropathology of specific phobias remains poorly understood. In the present study, we investigated whether patients with spider phobia show altered amygdala volumes as compared to healthy control subjects. Methods Twenty female patients with spider phobia and twenty age-matched healthy female controls underwent magnetic resonance imaging to investigate amygdala volumes. The amygdalae were segmented using an automatic, model-based segmentation tool (FSL FIRST). Differences in amygdala volume were investigated by multivariate analysis of covariance with group as between-subject factor and left and right amygdala as dependent factors. The relation between amygdala volume and clinical features such as symptom severity, disgust sensitivity, trait anxiety and duration of illness was investigated by Spearman correlation analysis. Results Spider phobic patients showed significantly smaller left amygdala volume than healthy controls. No significant difference in right amygdala volume was detected. Furthermore, the diminished amygdala size in patients was related to higher symptom severity, but not to higher disgust sensitivity or trait anxiety and was independent of age. Conclusions In summary, the results reveal a relation between higher symptom severity and smaller left amygdala volume in patients with spider phobia. This relation was independent of other potential confounders such as the disgust sensitivity or trait anxiety. The findings suggest that greater spider phobic fear is associated with smaller left amygdala. However, the smaller left amygdala volume may either stand for a higher vulnerability to develop a phobic disorder or emerge as a consequence of the disorder. PMID:23442196

  12. 23.4% saline decreases brain tissue volume in severe hepatic encephalopathy as assessed by a quantitative computed tomography marker

    Science.gov (United States)

    Liotta, Eric M; Lizza, Bryan D; Romanova, Anna L; Guth, James C; Berman, Michael D; Carroll, Timothy J; Francis, Brandon; Ganger, Daniel; Ladner, Daniela P; Maas, Matthew B; Naidech, Andrew M

    2016-01-01

    Objective Cerebral edema is common in severe hepatic encephalopathy and may be life-threatening. Bolus 23.4% hypertonic saline (HTS) improves surveillance neuromonitoring scores, although its mechanism of action is not clearly established. We investigated the hypothesis that bolus HTS decreases cerebral edema in severe hepatic encephalopathy utilizing a quantitative technique to measure brain and CSF volume changes. Design Retrospective analysis of serial computed tomography (CT) scans and clinical data for a case-control series was performed. Setting Intensive care units of a tertiary care hospital. Patients Patients with severe hepatic encephalopathy treated with 23.4% HTS and control patients who did not receive 23.4% HTS. Methods We used clinically obtained CT scans to measure volumes of the ventricles, intracranial CSF, and brain using a previously validated semi-automated technique (Analyze Direct; Overland Park, KS). Volumes before and after 23.4% HTS were compared with Wilcoxon signed-rank test. Associations between total CSF volume, ventricular volume, serum sodium, and Glasgow Coma Scale Scores were assessed using Spearman correlation. Results Eleven patients with 18 administrations of 23.4% HTS met inclusion criteria. Total CSF (median 47.6 [35.1–69.4] to 61.9 [47.7–87.0] mL, pbrain tissue volume. Total CSF and ventricular volume change may be useful quantitative measures to assess cerebral edema in severe hepatic encephalopathy. PMID:26308431

  13. Rho family GTP binding proteins are involved in the regulatory volume decrease process in NIH3T3 mouse fibroblasts

    DEFF Research Database (Denmark)

    Pedersen, Stine F; Beisner, Kristine H; Willumsen, Berthe M

    2002-01-01

    The role of Rho GTPases in the regulatory volume decrease (RVD) process following osmotic cell swelling is controversial and has so far only been investigated for the swelling-activated Cl- efflux. We investigated the involvement of RhoA in the RVD process in NIH3T3 mouse fibroblasts, using wild-...

  14. RBC volume deficiency in patients with excessive orthostatic decrease in cerebral blood flow velocity

    Directory of Open Access Journals (Sweden)

    Chun-Jen Lin

    2014-04-01

    Conclusion: The results of our study indicated that low RBC volume may play an important role in the pathophysiology of OI in this group of patients. Moreover, its role seems even more relevant in patients with POTS than in those without. Further studies for mechanistic evaluation are needed in the future.

  15. Error analysis of measuring diameter at breast height and tree height and volume of standing tree by total station%全站仪测量立木胸径树高及材积的误差分析

    Institute of Scientific and Technical Information of China (English)

    于东海; 冯仲科; 曹忠; 蒋君志伟

    2016-01-01

    Diameter at breast height (DBH), tree height and volume are the most significant factors in forestry investigation. The measurement precision of DBH and tree height directly affects the accuracy of individual volume. In traditional forestry works, cutting down trees and using analytic timber are for compiling the volume tables, which are yet faced with the problems such as high consumption, low efficiency and large destruction. In recent years, the emergence of the modern instruments gradually lays the foundation for achieving high precision nondestructive standing tree measurements. Total station is a kind of precise tool that can be used to measure distance and angle and to process data automatically. And it will be widely used in forestry production practice and scientific research in the future because of the high measurement accuracy, so studying the accuracy of measuring trees has practical significance for the forestry work. Calculating DBH, tree height and volume by measuring zenith angles, horizontal angles and distance from the center of the instrument to the tree is the principle of measuring standing trees by using total station. Based on the theory of measuring DBH, tree height and volume of standing tree by total station and taking the variance and covariance of measurement factors into consideration, the research deduced the mathematical models to calculate the error of DBH, height and volume of standing tree according to error propagation laws. We chose larches in Beijing as the experimental samples, and analyzed 10 sample groups of different sizes for the difference of relative errors. The results show: 1) There are correlations between the height and the diameter of random tree section, and the value range of correlation coefficientis (0, 0.3); besides, the variance and covariance of these 2 factors affect the error of each segment volume; furthermore, the error of total volume is affected not only by the variance of each section volume, but also

  16. Prenatal infection decreases calbindin, decreases Purkinje cell volume and density and produces long-term motor deficits in Sprague-Dawley rats.

    Science.gov (United States)

    Wallace, K; Veerisetty, S; Paul, I; May, W; Miguel-Hidalgo, J J; Bennett, W

    2010-01-01

    The cerebellum is involved in the control of motor functions with Purkinje cells serving as the only output from the cerebellum. Purkinje cells are important targets for toxic substances and are vulnerable to prenatal insults. Intrauterine infection (IUI) has been shown to selectively target the developing cerebral white matter through lesioning, necrosis and inflammatory cytokine activation. Developmental and cognitive delays have been associated with animal models of IUI. The aim of this study was to determine if IUI leads to damage to Purkinje cells in the developing cerebellum and if any damage is associated with decreases in calbindin and motor behaviors in surviving pups. Pregnant rats were injected with Escherichia coli (1 × 10⁵ colony-forming units) or sterile saline at gestational day 17. Beginning at postnatal day (PND) 2, the pups were subjected to a series of developmental tests to examine developmental milestones. At PND 16, some pups were sacrificed and their brains extracted and processed for histology or protein studies. Hematoxylin and eosin (HE) staining was done to examine the general morphology of the Purkinje cells and to examine Purkinje cell density, area and volume. Calbindin expression was examined in the cerebellum via immunohistochemistry and Western blot techniques. The remaining rat pups were used to examine motor coordination and balance on a rotating rotarod at the prepubertal and adult ages. Prenatal E. coli injection did not significantly change birth weight or delivery time, but did delay surface righting and negative geotaxis in pups. Pups in the E. coli group also had a decrease in the number of Purkinje cells, as well as a decrease in Purkinje cell density and volume. HE staining demonstrated a change in Purkinje cell morphology. Calbindin expression was decreased in rats from the E. coli group as well. Locomotor tests indicated that while there were no significant changes in gross motor activity, motor coordination and

  17. Interpreting stem diameter changes

    Science.gov (United States)

    Hölttä, T.; Sevanto, S.; Nikinmaa, E.

    2009-12-01

    Detecting phloem transport in stem diameter changes Teemu Hölttä1, Sanna Sevanto2, Eero Nikinmaa1 1Department of Forest Ecology, P.O. Box 27, FIN-00014 University of Helsinki, Finland 2Department of Physics, P.O. Box 48, FIN-00014 University of Helsinki, Finland Introduction The volume of living cells and xylem conduits vary according to pressures they are subjected to. Our proposition is that the behavior of the inner bark diameter variation which cannot be explained by changes in xylem water status arise from changes in the osmotic concentration of the phloem and cambial growth. Materials and methods Simultaneous xylem and stem diameter measurements were conducted between June 28th to October 4th 2006 in Southern Finland on a 47-year old, 15 meter tall, Scots pine tree (DBH 15 cm) at heights of 1.5 and 10 meters. The difference between the measured inner bark diameter and the inner bark diameter predicted from xylem diameter change with a simple model (assuming there was no change in the osmotic concentration of the phloem) is hypothesized to give the changes in the osmotic concentration of the inner bark. The simple model calculates the radial water exchange between the xylem and phloem driven by the water potential changes in the xylem. Results and Discussion The major signal in the inner bark diameter was the transpiration rate as assumed, but also a signal arising from the change in the osmotic concentration (Fig 1a). The predicted osmotic concentration of the phloem typically increased during the afternoon due to the loading of photosynthesized sugars to the phloem. Inner bark osmotic concentration followed the photosynthesis rate with a 3 and 4 hour time-lag at the top and base, respectively (Fig 1b). The connection between photosynthesis and the predicted change in phloem osmotic concentration was stronger in the upper part of the tree compared to lower part. The changes in the predicted osmotic concentration were not similar every day, indicating that

  18. Decreased premotor cortex volume in victims of urban violence with posttraumatic stress disorder.

    Directory of Open Access Journals (Sweden)

    Vanessa Rocha-Rego

    Full Text Available BACKGROUND: Studies addressing posttraumatic stress disorder (PTSD have demonstrated that PTSD patients exhibit structural abnormalities in brain regions that relate to stress regulation and fear responses, such as the hippocampus, amygdala, anterior cingulate cortex, and ventromedial prefrontal cortex. Premotor cortical areas are involved in preparing to respond to a threatening situation and in representing the peripersonal space. Urban violence is an important and pervasive cause of human suffering, especially in large urban centers in the developing world. Violent events, such as armed robbery, are very frequent in certain cities, and these episodes increase the risk of PTSD. Assaultive trauma is characterized by forceful invasion of the peripersonal space; therefore, could this traumatic event be associated with structural alteration of premotor areas in PTSD? METHODOLOGY/PRINCIPAL FINDINGS: Structural magnetic resonance imaging scans were acquired from a sample of individuals that had been exposed to urban violence. This sample consisted of 16 PTSD patients and 16 age- and gender-matched controls. Psychometric questionnaires differentiated PTSD patients from trauma-exposed controls with regard to PTSD symptoms, affective, and resilience predispositions. Voxel-based morphometric analysis revealed that, compared with controls, the PTSD patients presented significant reductions in gray matter volume in the ventral premotor cortex and in the pregenual anterior cingulate cortex. CONCLUSIONS: Volume reduction in the premotor cortex that is observed in victims of urban violence with PTSD may be associated with a disruption in the dynamical modulation of the safe space around the body. The finding that PTSD patients presented a smaller volume of pregenual anterior cingulate cortex is consistent with the results of other PTSD neuroimaging studies that investigated different types of traumatic events.

  19. Gray Matter Volume Decreases in Elderly Patients with Schizophrenia: A Voxel-based Morphometry Study

    Science.gov (United States)

    Schuster, Caroline; Schuller, Anne Marie; Paulos, Carlos; Namer, Izzie; Pull, Charles; Danion, Jean Marie; Foucher, Jack René

    2012-01-01

    Background: Aged patients (>50 years old) with residual schizophrenic symptoms differ from young patients. They represent a subpopulation with a more unfavorable Kraepelinian course and have an increased risk (up to 30%) for dementia of unknown origin. However, our current understanding of age-related brain changes in schizophrenia is derived from studies that included less than 17% of patients who were older than 50 years of age. This study investigated the anatomical distribution of gray matter (GM) brain deficits in aged patients with ongoing schizophrenia. Methods: Voxel-based morphometry was applied to 3D-T1 magnetic resonance images obtained from 27 aged patients with schizophrenia (mean age of 60 years) and 40 age-matched normal controls. Results: Older patients with schizophrenia showed a bilateral reduction of GM volume in the thalamus, the prefrontal cortex, and in a large posterior region centered on the occipito-temporo-parietal junction. Only the latter region showed accelerated GM volume loss with increasing age. None of these results could be accounted for by institutionalization, antipsychotic medication, or cognitive scores. Conclusions: This study replicated most common findings in patients with schizophrenia with regard to thalamic and frontal GM deficits. However, it uncovered an unexpected large region of GM atrophy in the posterior tertiary cortices. The latter observation may be specific to this aged and chronically symptomatic subpopulation, as atrophy in this region is rarely reported in younger patients and is accelerated with age. PMID:21205677

  20. Oyster's cells regulatory volume decrease: A new tool for evaluating the toxicity of low concentration hydrocarbons in marine waters.

    Science.gov (United States)

    Ben Naceur, Chiraz; Maxime, Valérie; Ben Mansour, Hedi; Le Tilly, Véronique; Sire, Olivier

    2016-11-01

    Human activities require fossil fuels for transport and energy, a substantial part of which can accidentally or voluntarily (oil spillage) flow to the marine environment and cause adverse effects in human and ecosystems' health. This experiment was designed to estimate the suitability of an original cellular biomarker to early quantify the biological risk associated to hydrocarbons pollutants in seawater. Oocytes and hepatopancreas cells, isolated from oyster (Crassostrea gigas), were tested for their capacity to regulate their volume following a hypo-osmotic challenge. Cell volumes were estimated from cell images recorded at regular time intervals during a 90min-period. When exposed to diluted seawater (osmolalities from 895 to 712mosmkg(-1)), both cell types first swell and then undergo a shrinkage known as Regulatory Volume Decrease (RVD). This process is inversely proportional to the magnitude of the osmotic shock and is best fitted using a first-order exponential decay model. The Recovered Volume Factor (RVF) calculated from this model appears to be an accurate tool to compare cells responses. As shown by an about 50% decrease in RVF, the RVD process was significantly inhibited in cells sampled from oysters previously exposed to a low concentration of diesel oil (8.4mgL(-1) during 24h). This toxic effect was interpreted as a decreased permeability of the cell membranes resulting from an alteration of their lipidic structure by diesel oil compounds. In contrast, the previous contact of oysters with diesel did not induce any rise in the gills glutathione S-transferase specific activity. Therefore, this work demonstrates that the study of the RVD process of cells selected from sentinel animal species could be an alternative bioassay for the monitoring of hydrocarbons and probably, of various chemicals in the environment liable to alter the cellular regulations. Especially, given the high sensitivity of this biomarker compared with a proven one, it could become a

  1. Cell volume control in phospholemman (PLM) knockout mice: do cardiac myocytes demonstrate a regulatory volume decrease and is this influenced by deletion of PLM?

    Science.gov (United States)

    Bell, James R; Lloyd, David; Curl, Claire L; Delbridge, Lea M D; Shattock, Michael J

    2009-03-01

    In addition to modulatory actions on Na+-K+-ATPase, phospholemman (PLM) has been proposed to play a role in cell volume regulation. Overexpression of PLM induces ionic conductances, with 'PLM channels' exhibiting selectivity for taurine. Osmotic challenge of host cells overexpressing PLM increases taurine efflux and augments the cellular regulatory volume decrease (RVD) response, though a link between PLM and cell volume regulation has not been studied in the heart. We recently reported a depressed cardiac contractile function in PLM knockout mice in vivo, which was exacerbated in crystalloid-perfused isolated hearts, indicating that these hearts were osmotically challenged. To address this, the present study investigated the role of PLM in osmoregulation in the heart. Isolated PLM wild-type and knockout hearts were perfused with a crystalloid buffer supplemented with mannitol in a bid to prevent perfusate-induced cell swelling and maintain function. Accordingly, and in contrast to wild-type control hearts, contractile function was improved in PLM knockout hearts with 30 mM mannitol. To investigate further, isolated PLM wild-type and knockout cardiomyocytes were subjected to increasing hyposmotic challenges. Initial validation studies showed the IonOptix video edge-detection system to be a simple and accurate 'real-time' method for tracking cell width as a marker of cell size. Myocytes swelled equally in both genotypes, indicating that PLM, when expressed at physiological levels in cardiomyocytes, is not essential to limit water accumulation in response to a hyposmotic challenge. Interestingly, freshly isolated adult cardiomyocytes consistently failed to mount RVDs in response to cell swelling, adding to conflicting reports in the literature. A proposed perturbation of the RVD response as a result of the cell isolation process was not restored, however, with short-term culture in either adult or neonatal cardiomyocytes.

  2. Sea Water Acidification Affects Osmotic Swelling, Regulatory Volume Decrease and Discharge in Nematocytes of the Jellyfish Pelagia noctiluca

    Directory of Open Access Journals (Sweden)

    Rossana Morabito

    2013-12-01

    Full Text Available Background: Increased acidification/PCO2 of sea water is a threat to the environment and affects the homeostasis of marine animals. In this study, the effect of sea water pH changes on the osmotic phase (OP, regulatory volume decrease (RVD and discharge of the jellyfish Pelagia noctiluca (Cnidaria, Scyphozoa nematocytes, collected from the Strait of Messina (Italy, was assessed. Methods: Isolated nematocytes, suspended in artificial sea water (ASW with pH 7.65, 6.5 and 4.5, were exposed to hyposmotic ASW of the same pH values and their osmotic response and RVD measured optically in a special flow through chamber. Nematocyte discharge was analyzed in situ in ASW at all three pH values. Results: At normal pH (7.65, nematocytes subjected to hyposmotic shock first expanded osmotically and then regulated their cell volume within 15 min. Exposure to hyposmotic ASW pH 6.5 and 4.5 compromised the OP and reduced or totally abrogated the ensuing RVD, respectively. Acidic pH also significantly reduced the nematocyte discharge response. Conclusion: Data indicate that the homeostasis and function of Cnidarians may be altered by environmental changes such as sea water acidification, thereby validating their use as novel bioindicators for the quality of the marine environment.

  3. Visceral sensitivity correlates with decreased regional gray matter volume in healthy volunteers: a voxel-based morphometry study.

    Science.gov (United States)

    Elsenbruch, Sigrid; Schmid, Julia; Kullmann, Jennifer S; Kattoor, Joswin; Theysohn, Nina; Forsting, Michael; Kotsis, Vassilios

    2014-02-01

    Regional changes in brain structure have been reported in patients with altered visceral sensitivity and chronic abdominal pain, such as in irritable bowel syndrome. It remains unknown whether structural brain changes are associated with visceral sensitivity. Therefore, we present the first study in healthy individuals to address whether interindividual variations in gray matter volume (GMV) in pain-relevant regions correlate with visceral sensitivity. In 92 healthy young adults (52 female), we assessed rectal sensory and pain thresholds and performed voxel-based morphometry (VBM) to compute linear regression models with visceral sensory and pain thresholds, respectively, as independent variable and GMV in a priori-defined regions of interest (ROIs) as dependent variable. All results were familywise error (FWE) corrected at a level of PFWEpain, without evidence of sex differences. Lower rectal sensory threshold (ie, increased sensitivity) correlated significantly with reduced GMV in the thalamus, insula, posterior cingulate cortex, ventrolateral and orbitofrontal prefrontal cortices, amygdala, and basal ganglia (all PFWEpain threshold was associated with reduced GMV in the right thalamus (PFWE=.051). These are the first data supporting that increased visceral sensitivity correlates with decreased gray matter volume in pain-relevant brain regions. These findings support that alterations in brain morphology not only occur in clinical pain conditions but also occur according to normal interindividual variations in visceral sensitivity. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  4. 桂东区杉木地径与胸径、树高、材积相关分析%Correlation Analysis of Ground Diameter and DBH, Tree Height and Volume of Cunninghamia lanceolata in East Guangxi

    Institute of Scientific and Technical Information of China (English)

    闭海秀; 黄清经

    2014-01-01

    Using ground diameter, DBH and tree height of Cunninghamia lanceolata from the control samples of second class investigation in Zhaoping county, Hezhou city, Guaingxi in 2009 as the sample data, and using the SPSS statistical analysis software and the knowledge of mathematical statistics, the correlation about the ground diameter and DBH, tree height and volume was analyzed. The correlations or curve regression models on ground diameter and DBH, and ground diameter and volume were established and the optimal model was selected , which could be used to calculate DBH and volume by ground diam-eter. The results showed that the ground diameter and tree height accumulated in strong positive correla-tion. The best regression model of ground diameter from 6cm to 20cm and DBH was D1. 3 = -0. 199 +0. 851D地. The regression model of ground diameter from 22cm to 40cm and DBH was D1. 3 = -1. 652+0. 913 D地, with precision 98. 7 %. Ground diameter and DBH also had a strong positive linear correla-tion. Regression model of the ground diameter and volume was V =0. 000 082D地2. 486 79 with precision 95. 2 %. The precision of the models built in this time was within permitted, which could be used in practice.%利用广西昭平县2009年二类调查控制样点的数据中的杉木的地径和胸径、树高为样本数据,并通过SPSS统计分析软件和数理统计知识,对地径与胸径、树高和材积的相关关系进行分析,分别建立地径与胸径、地径与材积的相关关系或曲线回归模型,最后选出最优模型,从而可利用模型由地径推算胸径和材积。结果表明,地径与树高存在显著正相关性,且地径6~20 cm 径阶与胸径之间最佳的回归模型为 D1.3=-0.199+0.851D地,地径22~40 cm径阶与胸径之间回归模型为D1.3=-1.652+0.913D地,精度是98.7%;同时地径与胸径也存在显著的正线性相关性,地径与材积的回归模型为V=0.000082D地2.48679,精度为95.2%。本次

  5. Rho family GTP binding proteins are involved in the regulatory volume decrease process in NIH3T3 mouse fibroblasts.

    Science.gov (United States)

    Pedersen, Stine F; Beisner, Kristine H; Hougaard, Charlotte; Willumsen, Berthe M; Lambert, Ian H; Hoffmann, Else K

    2002-06-15

    The role of Rho GTPases in the regulatory volume decrease (RVD) process following osmotic cell swelling is controversial and has so far only been investigated for the swelling-activated Cl- efflux. We investigated the involvement of RhoA in the RVD process in NIH3T3 mouse fibroblasts, using wild-type cells and three clones expressing constitutively active RhoA (RhoAV14). RhoAV14 expression resulted in an up to fourfold increase in the rate of RVD, measured by large-angle light scattering. The increase in RVD rate correlated with RhoAV14 expression. RVD in wild-type cells was unaffected by the Rho kinase inhibitor Y-27632 and the phosphatidyl-inositol 3 kinase (PI3K) inhibitor wortmannin. The maximal rates of swelling-activated K+ (86 Rb+ as tracer) and taurine ([3H]taurine as tracer) efflux after a 30 % reduction in extracellular osmolarity were increased about twofold in cells with maximal RhoAV14 expression compared to wild-type cells, but were unaffected by Y-27632. The volume set points for activation of release of both osmolytes appeared to be reduced by RhoAV14 expression. The maximal taurine efflux rate constant was potentiated by the tyrosine phosphatase inhibitor Na(3)VO(4), and inhibited by the tyrosine kinase inhibitor genistein. The magnitude of the swelling-activated Cl- current (I(Cl,swell) ) was higher in RhoAV14 than in wild-type cells after a 7.5 % reduction in extracellular osmolarity, but, in contrast to 86Rb+ and [3H]taurine efflux, similar in both strains after a 30 % reduction in extracellular osmolarity. I(Cl,swell) was inhibited by Y-27632 and strongly potentiated by the myosin light chain kinase inhibitors ML-7 and AV25. It is suggested that RhoA, although not the volume sensor per se, is an important upstream modulator shared by multiple swelling-activated channels on which RhoA exerts its effects via divergent signalling pathways.

  6. Dependence of Regulatory Volume Decrease on Transient Receptor Potential Vanilloid 4 (TRPV4) Expression in Human Corneal Epithelial Cells

    Science.gov (United States)

    Pan, Zan; Yang, Hua; Mergler, Stefan; Liu, Hongshan; Tachado, Souvenir D.; Zhang, Fan; Kao, Winston W. Y.; Koziel, Henry; Pleyer, Uwe; Reinach, Peter S.

    2008-01-01

    TRPV4 is a non-selective cation channel with moderate calcium permeability, which is activated by exposure to hypotonicity. Such a stress induces regulatory volume decrease (RVD) behavior in human corneal epithelial cells (HCEC). We hypothesize that TRPV4 channel mediates RVD in HCEC. Immunohistochemistry revealed centrally and superficially concentrated TRPV4 localization in the corneal tissue. Immunocytochemical and Fluorescence Activated Cell Sorter (FACS) analyses identified TRPV4 membrane surface and cytosolic expression. RT-PCR and Western blot analyses identified TRPV4 gene and protein expression in HCEC, respectively. In addition, 4α-PDD or a 50% hypotonic medium induced up to three-fold transient intracellular Ca2+ ([Ca2+]i) increases. Following TRPV4 siRNA HCEC transfection, its protein expression level declined by 64%, which abrogated these [Ca2+]i transients. Similarly, exposure to either ruthenium red or Ca2+-free Ringer's solution also eliminated this response. In these transfected cells, RVD declined by 51% whereas in the non-transfected counterpart, ruthenium red and Ca2+-free solution inhibited RVD by 54% and 64%, respectively. In contrast, capsazepine, a TRPV1 antagonist, failed to suppress [Ca2+]i transients and RVD. TRPV4 activation contributes to RVD since declines in TRPV4 expression and activity are associated with suppression of this response. In conclusion, there is TRPV4 functional expression in HCEC. PMID:18355916

  7. Reactive oxygen species are related to ionic fluxes and volume decrease in apoptotic cerebellar granule neurons: role of NOX enzymes.

    Science.gov (United States)

    Hernández-Enríquez, Berenice; Guemez-Gamboa, Alicia; Morán, Julio

    2011-05-01

    Reactive oxygen species (ROS) are produced early during apoptosis of cerebellar granule neurons induced by low potassium (K5) and staurosporine (Sts). In addition, K5 and Sts activate NADPH oxidases (NOX). Recently, we described that K5 and Sts induce apoptotic volume decrease (AVD) at a time when ROS generation and NOX activity occur. In the present study, we evaluated the relationship between ROS generation and ionic fluxes during AVD. Here, we showed that K5- and Sts-induced AVD was inhibited by antioxidants and that direct ROS production induced AVD. Moreover, NOX inhibitors eliminated AVD induced by both K5 and Sts. Sts, but not K5, failed to induce AVD in cerebellar granule neurons from NOX2 knockout mice. These findings suggest that K5- and Sts-induced AVD is largely mediated by ROS produced by NOX. On the other hand, we also found that the blockage of ionic fluxes involved in AVD inhibited both ROS generation and NOX activity. These findings suggest that ROS generation and NOX activity are involved in ionic fluxes activation, which in turn could maintain ROS generation by activating NOX, leading to a self-amplifying cycle.

  8. Clinical usefulness of the definitions for defining characteristics of activity intolerance, excess fluid volume and decreased cardiac output in decompensated heart failure: a descriptive exploratory study.

    Science.gov (United States)

    de Souza, Vanessa; Zeitoun, Sandra Salloum; Lopes, Camila Takao; de Oliveira, Ana Paula Dias; Lopes, Juliana de Lima; de Barros, Alba Lucia Bottura Leite

    2015-09-01

    To assess the clinical usefulness of the operational definitions for the defining characteristics of the NANDA International nursing diagnoses, activity intolerance, decreased cardiac output and excess fluid volume, and the concomitant presence of those diagnoses in patients with decompensated heart failure. Content validity of the operational definitions for the defining characteristics of activity intolerance, excess fluid volume and decreased cardiac output have been previously validated by experts. Their clinical usefulness requires clinical validation. This was a descriptive exploratory study. Two expert nurses independently assessed 25 patients with decompensated heart failure for the presence or absence of 29 defining characteristics. Interrater reliability was analysed using the Kappa coefficient as a measure of clinical usefulness. The Fisher's exact test was used to test the association of the defining characteristics of activity intolerance and excess fluid volume in the presence of decreased cardiac output, and the correlation between the three diagnoses. Assessments regarding the presence of all defining characteristics reached 100% agreement, except with anxiety. Five defining characteristics of excess fluid volume were significantly associated with the presence of decreased cardiac output. Concomitant presence of the three diagnoses occurred in 80% of the patients. However, there was no significant correlation between the three diagnoses. The operational definitions for the diagnoses had strong interrater reliability, therefore they were considered clinically useful. Only five defining characteristics were representative of the association between excess fluid volume and decreased cardiac output. Therefore, excess fluid volume is related to decreased cardiac output, although these diagnoses are not necessarily associated with activity intolerance. The operational definitions may favour early recognition of the sequence of responses to decompensation

  9. Potassium-chloride cotransporter 3 interacts with Vav2 to synchronize the cell volume decrease response with cell protrusion dynamics.

    Directory of Open Access Journals (Sweden)

    Adèle Salin-Cantegrel

    Full Text Available Loss-of-function of the potassium-chloride cotransporter 3 (KCC3 causes hereditary motor and sensory neuropathy with agenesis of the corpus callosum (HMSN/ACC, a severe neurodegenerative disease associated with defective midline crossing of commissural axons in the brain. Conversely, KCC3 over-expression in breast, ovarian and cervical cancer is associated with enhanced tumor cell malignancy and invasiveness. We identified a highly conserved proline-rich sequence within the C-terminus of the cotransporter which when mutated leads to loss of the KCC3-dependent regulatory volume decrease (RVD response in Xenopus Laevis oocytes. Using SH3 domain arrays, we found that this poly-proline motif is a binding site for SH3-domain containing proteins in vitro. This approach identified the guanine nucleotide exchange factor (GEF Vav2 as a candidate partner for KCC3. KCC3/Vav2 physical interaction was confirmed using GST-pull down assays and immuno-based experiments. In cultured cervical cancer cells, KCC3 co-localized with the active form of Vav2 in swelling-induced actin-rich protruding sites and within lamellipodia of spreading and migrating cells. These data provide evidence of a molecular and functional link between the potassium-chloride co-transporters and the Rho GTPase-dependent actin remodeling machinery in RVD, cell spreading and cell protrusion dynamics, thus providing new insights into KCC3's involvement in cancer cell malignancy and in corpus callosum agenesis in HMSN/ACC.

  10. On the role of calcium in the regulatory volume decrease (RVD) response in Ehrlich mouse ascites tumor cells

    DEFF Research Database (Denmark)

    Jørgensen, Nanna K.; Christensen, Søren; Harbak, Henrik;

    1997-01-01

    Fysiologi, volume regulation, phosphoinositidase C, Ins(1,4,5)P*U3, Ca*O2*O+-signaling, K*O+ channels, charybdotoxin, clotrimazole......Fysiologi, volume regulation, phosphoinositidase C, Ins(1,4,5)P*U3, Ca*O2*O+-signaling, K*O+ channels, charybdotoxin, clotrimazole...

  11. Two Years of Cinacalcet Hydrochloride Treatment Decreased Parathyroid Gland Volume and Serum Parathyroid Hormone Level in Hemodialysis Patients With Advanced Secondary Hyperparathyroidism.

    Science.gov (United States)

    Yamada, Shunsuke; Tokumoto, Masanori; Taniguchi, Masatomo; Toyonaga, Jiro; Suehiro, Takaichi; Eriguchi, Rieko; Fujimi, Satoru; Ooboshi, Hiroaki; Kitazono, Takanari; Tsuruya, Kazuhiko

    2015-08-01

    The long-term effect of cinacalcet hydrochloride treatment on parathyroid gland (PTG) volume has been scarcely investigated in patients with moderate to advanced secondary hyperparathyroidism (SHPT). The present study was a prospective observational study to determine the effect of cinacalcet treatment on PTG volume and serum biochemical parameters in 60 patients with renal SHPT, already treated with intravenous vitamin D receptor activator (VDRA). Measurement of biochemical parameters and PTG volumes were performed periodically, which were analyzed by stratification into tertiles across the baseline parathyroid hormone (PTH) level or PTG volume. We also determined the factors that can estimate the changes in PTG volume and the achievement of the target PTH range by multivariable analyses. Two years of cinacalcet treatment significantly decreased the serum levels of PTH, calcium, and phosphate, followed by the improvement of achieving the target ranges for these parameters recommended by the Japanese Society for Dialysis Therapy. Cinacalcet decreased the maximal and total PTG volume by about 30%, and also decreased the serum PTH level independent of the baseline serum PTH level and PTG volume. Ten out of 60 patients showed 30% increase in maximal PTG after 2 years. Multivariable analysis showed that patients with nodular PTG at baseline and patients with higher serum calcium and PTH levels at 1 year were likely to exceed the target range of PTH at two years. In conclusion, cinacalcet treatment with intravenous VDRA therapy decreased both PTG volume and serum intact PTH level, irrespective of the pretreatment PTG status and past treatment history. © 2015 The Authors. Therapeutic Apheresis and Dialysis © 2015 International Society for Apheresis.

  12. Decrease in temporal gyrus gray matter volume in first-episode, early onset schizophrenia: an MRI study.

    Directory of Open Access Journals (Sweden)

    Jinsong Tang

    Full Text Available BACKGROUND: Loss of gray matter has been previously found in early-onset schizophrenic patients. However, there are no consistent findings between studies due to different methods used to measure grey matter volume/density and influences of confounding factors. METHODS: The volume of gray matter (GM was measured in 29 first episode early-onset schizophrenia (EOS and 34 well-matched healthy controls by using voxel-based morphometry (VBM. Psychotic symptoms were assessed using the Positive and Negative Syndrome Scale (PANSS. The correlations between the GM volume and PANSS scores, age of psychosis onset, duration of psychosis, and chlorpromazine (CPZ equivalent value were investigated. RESULTS: Relative to healthy subjects, the patients with first episode EOS showed significantly lower GM volume in the left middle and superior temporal gyrus. The loss of GM volume negatively correlated with PANSS-positive symptoms (p = 0.002, but not with PANSS-negative symptoms, PANSS-general psychopathology, and PANSS-total score. No significant correlation was found between GM volume and age of psychosis onset, duration of psychosis, and CPZ equivalent value. CONCLUSION: Patients with first episode EOS have evidence of reduced GM in the left middle and superior temporal gyrus. Structural abnormalities in the left middle and superior temporal gyrus may contribute to the pathophysiology of schizophrenia.

  13. Dentate gyrus-cornu ammonis (CA) 4 volume is decreased and associated with depressive episodes and lipid peroxidation in bipolar II disorder: Longitudinal and cross-sectional analyses.

    Science.gov (United States)

    Elvsåshagen, Torbjørn; Zuzarte, Pedro; Westlye, Lars T; Bøen, Erlend; Josefsen, Dag; Boye, Birgitte; Hol, Per K; Malt, Ulrik F; Young, L Trevor; Andreazza, Ana C

    2016-12-01

    Reduced dentate gyrus volume and increased oxidative stress have emerged as potential pathophysiological mechanisms in bipolar disorder. However, the relationship between dentate gyrus volume and peripheral oxidative stress markers remains unknown. Here, we examined dentate gyrus-cornu ammonis (CA) 4 volume longitudinally in patients with bipolar II disorder (BD-II) and healthy controls and investigated whether BD-II is associated with elevated peripheral levels of oxidative stress. We acquired high-resolution structural 3T-magnetic resonance imaging (MRI) images and quantified hippocampal subfield volumes using an automated segmentation algorithm in individuals with BD-II (n=29) and controls (n=33). The participants were scanned twice, at study inclusion and on average 2.4 years later. In addition, we measured peripheral levels of two lipid peroxidation markers (4-hydroxy-2-nonenal [4-HNE] and lipid hydroperoxides [LPH]). First, we demonstrated that the automated hippocampal subfield segmentation technique employed in this work reliably measured dentate gyrus-CA4 volume. Second, we found a decreased left dentate gyrus-CA4 volume in patients and that a larger number of depressive episodes between T1 and T2 predicted greater volume decline. Finally, we showed that 4-HNE was elevated in BD-II and that 4-HNE was negatively associated with left and right dentate gyrus-CA4 volumes in patients. These results are consistent with a role for the dentate gyrus in the pathophysiology of bipolar disorder and suggest that depressive episodes and elevated oxidative stress might contribute to hippocampal volume decreases. In addition, these findings provide further support for the hypothesis that peripheral lipid peroxidation markers may reflect brain alterations in bipolar disorders. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. The volume of Purkinje cells decreases in the cerebellum of acrylamide-intoxicated rats, but no cells are lost

    DEFF Research Database (Denmark)

    Larsen, Jytte Overgaard; Tandrup, T; Braendgaard, H

    1994-01-01

    The effects of acrylamide intoxication on the numbers of granule and Purkinje cells and the volume of Purkinje cell perikarya have been evaluated with stereological methods. The analysis was carried out in the cerebella of rats that had received a dose of 33.3 mg/kg acrylamide, twice a week, for 7...

  15. Deregulation of apoptotic volume decrease and ionic movements in multidrug-resistant tumor cells: role of chloride channels

    DEFF Research Database (Denmark)

    Poulsen, Kristian Arild; Andersen, E C; Hansen, C F

    2010-01-01

    3728 inhibited AVD and completely abolished the differences in AVD, ionic movements, and caspase 3 activation between WT and MDR EATC. Finally, the maximal capacity of volume-regulated anion channel was found to be strongly repressed in MDR EATC. Together, these data suggest that impairment of AVD......, MDR EATC underwent a less pronounced AVD(1,) an augmented AVD(T), and a delay in induction of AVD(2). Changes in AVD were associated with inhibition of Cl(-) loss during AVD(1), augmented NaCl uptake during AVD(T), and a delay of Cl(-) loss during AVD(2). Application of the anion channel inhibitor NS...

  16. 应用固定砂石总体积法配制大粒径自密实混凝土%Preparation of self-compacting concrete with large diameter aggregate by fixed total volume of sand and gravel

    Institute of Scientific and Technical Information of China (English)

    危加阳; 罗竹容

    2014-01-01

    The method of fixed volume of sand and gravel is commonly used in mixture proportion design of self-compacting concrete. In order to return to the natural properties of aggregate, the method of fixed total volume of sand and gravel that is dif-ferent from the traditional concept is proposed, i. e. , in the mixture proportion design of self-compacting concrete, we should ensure it completely enwrapped, separated and suspended by cementing material. Moreover, this method is also applied in the preparation of self-compacting concrete with the maximum size of 31. 5 mm of coarse aggregate. The practices show that the self-compacting concrete still has good stability of anti-segregation and demonstrates that the preparation of self-compacting con-crete with large diameter aggregate by fixed total volume of sand and gravel is feasible.%固定砂石体积法是设计自密实混凝土配合比的常用方法。为回归骨料的天然属性,提出了有别于传统概念的固定砂石总体积法,即在配制自密实混凝土时,按胶凝材料浆包裹、分隔、悬浮总骨料为目标进行配比计算。同时,在工程实际中,利用该方法尝试将最大粒径为31.5 mm且具有较好抗离析稳定性的粗骨料用于自密实混凝土配制。实践证明,利用固定砂石总体积法配制较大粒径骨料自密实混凝土是可行的。

  17. 利用误差变量联立方程组建立南方杉木一元立木材积模型和胸径地径回归模型%Using Error-in-Variable Simultaneous Equations Approach to Construct One-way Tree Volume Models and Diameter at Breast Height-Diameter on Root Collar Regression Model for Chinese Fir (Cunninghamia lanceolata) in Southern China

    Institute of Scientific and Technical Information of China (English)

    曾伟生

    2012-01-01

    利用我国南方的杉木实测数据,采用误差变量联立方程组方法,同时建立了胸径一元材积模型、地径一元材积模型和胸径一地径回归模型。结果表明:地径与胸径之间相关紧密,其回归模型的确定系数可以达到0.96以上;地径一元材积模型的预估精度要明显低于胸径一元材积模型。%Based on the data of Chinese fir ( Cunninghamia lanceolata) in southern China, three models, DBH (Diameter at Breast Height ) -based volume model, DRC (Diameter on Root Collar)-based volume model, and DBH-DRC regression model, were constructed using the error-in-variabl~ simultaneous equations approach. The results showed that DBH is closely related to DRC, determination coefficient of the regression is more than 0. 96 ; and the prediction precision of DRC-based volume model is clearly lower than that of DBH-based volume model.

  18. Adenovirus-mediated hAQP1 expression in irradiated mouse salivary glands causes recovery of saliva secretion by enhancing acinar cell volume decrease.

    Science.gov (United States)

    Teos, L Y; Zheng, C-Y; Liu, X; Swaim, W D; Goldsmith, C M; Cotrim, A P; Baum, B J; Ambudkar, I S

    2016-07-01

    Head and neck irradiation (IR) during cancer treatment causes by-stander effects on the salivary glands leading to irreversible loss of saliva secretion. The mechanism underlying loss of fluid secretion is not understood and no adequate therapy is currently available. Delivery of an adenoviral vector encoding human aquaporin-1 (hAQP1) into the salivary glands of human subjects and animal models with radiation-induced salivary hypofunction leads to significant recovery of saliva secretion and symptomatic relief in subjects. To elucidate the mechanism underlying loss of salivary secretion and the basis for AdhAQP1-dependent recovery of salivary gland function we assessed submandibular gland function in control mice and mice 2 and 8 months after treatment with a single 15-Gy dose of IR (delivered to the salivary gland region). Salivary secretion and neurotransmitter-stimulated changes in acinar cell volume, an in vitro read-out for fluid secretion, were monitored. Consistent with the sustained 60% loss of fluid secretion following IR, a carbachol (CCh)-induced decrease in acinar cell volume from the glands of mice post IR was transient and attenuated as compared with that in cells from non-IR age-matched mice. The hAQP1 expression in non-IR mice induced no significant effect on salivary fluid secretion or CCh-stimulated cell volume changes, except in acinar cells from 8-month group where the initial rate of cell shrinkage was increased. Importantly, the expression of hAQP1 in the glands of mice post IR induced recovery of salivary fluid secretion and a volume decrease in acinar cells to levels similar to those in cells from non-IR mice. The initial rates of CCh-stimulated cell volume reduction in acinar cells from hAQP1-expressing glands post IR were similar to those from control cells. Altogether, the data suggest that expression of hAQP1 increases the water permeability of acinar cells, which underlies the recovery of fluid secretion in the salivary glands

  19. Establishment of basal diameter relevant models and volume table for Quercus variabilis in northern China.%华北地区栓皮栎根径相关模型及材积表研建

    Institute of Scientific and Technical Information of China (English)

    郑聪慧; 贾黎明; 孙操稳; 魏松坡; 段劼

    2015-01-01

    Based on the data of 149 analytical sample trees, we established three well-performed independent models:1) a linear model between diameter at breast height outside bark ( DBHob ) and basal diameter inside bark (BDib) (DBHob-BDib), 2) a power function model between DBHob and tree height (H) (DBHob-H), and 3) a linear model between DBHob, H and volume inside bark (Vib) (DBHob, H-Vib) based on the variables after natural logarithmic transformation. Then, based on these three independent models, a compatible BDib-DBHob-H-Vib model system was established with the method of simultaneous equations with error variables, and thus compatible volume equations ( table) based on BDib-DBHob and DBHob-H were obtained. According to the results of six statistical indexes, residual plots, Shapiro Wilk tests and independent data tests for each model, heteroscedasticities were not detected in these models and residuals of these models followed a normal distribution. Ranges of residuals of these models in fitting and testing phases were very narrow, compared with the ranges of dependent variables. The volume table had promising precisions, thus they could be used for estimating Quercus variabilis volume and can provide support for dealing with illegal logging or deforestation cases of cork oak forests in northern China. As an important component of forest growth and yield model system, DBHob-H model can be used to estimate average tree height given a known DBHob, and on this basis, forest volume and biomass could be calculated eventually. Therefore, the DBHob-H model is very important in forest survey. We should point out that models established in this study are only applicable for cork oak trees in northern China with a DBHob range of 5-21 cm.%基于华北地区149株栓皮栎解析木的数据,先建立了3个表现良好的独立模型,包括带皮胸径- 去皮根径线性模型、带皮胸径-树高幂函数模型和基于自然对数转换变量的带皮胸径、树高-去皮

  20. Mechanical ventilation with high tidal volumes attenuates myocardial dysfunction by decreasing cardiac edema in a rat model of LPS-induced peritonitis

    Directory of Open Access Journals (Sweden)

    Smeding Lonneke

    2012-03-01

    Full Text Available Abstract Background Injurious mechanical ventilation (MV may augment organ injury remote from the lungs. During sepsis, myocardial dysfunction is common and increased endothelial activation and permeability can cause myocardial edema, which may, among other factors, hamper myocardial function. We investigated the effects of MV with injuriously high tidal volumes on the myocardium in an animal model of sepsis. Methods Normal rats and intraperitoneal (i.p. lipopolysaccharide (LPS-treated rats were ventilated with low (6 ml/kg and high (19 ml/kg tidal volumes (Vt under general anesthesia. Non-ventilated animals served as controls. Mean arterial pressure (MAP, central venous pressure (CVP, cardiac output (CO and pulmonary plateau pressure (Pplat were measured. Ex vivo myocardial function was measured in isolated Langendorff-perfused hearts. Cardiac expression of endothelial vascular cell adhesion molecule (VCAM-1 and edema were measured to evaluate endothelial inflammation and leakage. Results MAP decreased after LPS-treatment and Vt-dependently, both independent of each other and with interaction. MV Vt-dependently increased CVP and Pplat and decreased CO. LPS-induced peritonitis decreased myocardial function ex vivo but MV attenuated systolic dysfunction Vt-dependently. Cardiac endothelial VCAM-1 expression was increased by LPS treatment independent of MV. Cardiac edema was lowered Vt-dependently by MV, particularly after LPS, and correlated inversely with systolic myocardial function parameters ex vivo. Conclusion MV attenuated LPS-induced systolic myocardial dysfunction in a Vt-dependent manner. This was associated with a reduction in cardiac edema following a lower transmural coronary venous outflow pressure during LPS-induced coronary inflammation.

  1. Decreased Bone Volume and Bone Mineral Density in the Tibial Trabecular Bone Is Associated with Per2 Gene by 405 nm Laser Stimulation

    Directory of Open Access Journals (Sweden)

    Yeong-Min Yoo

    2015-11-01

    Full Text Available Low-level laser therapy/treatment (LLLT using a minimally invasive laser needle system (MILNS might enhance bone formation and suppress bone resorption. In this study, the use of 405 nm LLLT led to decreases in bone volume and bone mineral density (BMD of tibial trabecular bone in wild-type (WT and Per2 knockout (KO mice. Bone volume and bone mineral density of tibial trabecular bone was decreased by 405 nm LLLT in Per2 KO compared to WT mice at two and four weeks. To determine the reduction in tibial bone, mRNA expressions of alkaline phosphatase (ALP and Per2 were investigated at four weeks after 405 nm laser stimulation using MILNS. ALP gene expression was significantly reduced in the LLLT-stimulated right tibial bone of WT and Per2 KO mice compared to the non-irradiated left tibia (p < 0.001. Per2 mRNA expression in WT mice was significantly reduced in the LLLT-stimulated right tibial bone compared to the non-irradiated left tibia (p < 0.001. To identify the decrease in tibial bone mediated by the Per2 gene, levels of runt-related transcription factor 2 (Runx2 and ALP mRNAs were determined in non-irradiated WT and Per2 KO mice. These results demonstrated significant downregulation of Runx2 and ALP mRNA levels in Per2 KO mice (p < 0.001. Therefore, the reduction in tibial trabecular bone resulting from 405 nm LLLT using MILNS might be associated with Per2 gene expression.

  2. A correlation between decreased parathyroid α-Klotho and fibroblast growth factor receptor 1 expression with pathological category and parathyroid gland volume in dialysis patients.

    Science.gov (United States)

    Yan, Junfang; Jingbo, Chen; Wang, Deguang; Xie, Shengxue; Yuan, Liang; Zhong, Xing; Hao, Li

    2015-04-01

    The objective of this study was to investigate α-Klotho and fibroblast growth factor receptor 1 (FGFR1) expression in hyperplastic parathyroid glands, as well as their role in the development of renal hyperparathyroidism. Hyperplastic parathyroid glands (n = 90) were obtained from 24 patients who received parathyroidectomy due to secondary renal hyperparathyroidism. Normal parathyroid tissue was obtained from glands (n = 6) that were inadvertently removed, in conjunction with thyroidectomy, from patients with thyroid carcinoma. The expression of α-Klotho and FGFR1 in the parathyroid tissue was detected using immunohistochemical staining. The expression of α-Klotho and FGFR1 was significantly reduced in the hyperplastic parathyroid tissue compared to that in the normal parathyroid tissue. The expression of α-Klotho decreased further with increasing parathyroid pathology. A significant positive correlation was observed between α-Klotho and FGFR1 (r = 0.38, P < 0.01). FGFR1 (r = -0.21, P < 0.05) and α-Klotho (r = -0.42, P < 0.01) were negatively correlated with the volume of the hyperplastic parathyroid tissue. The expression of α-Klotho and FGFR1 decreases in the parathyroid glands of dialysis patients with secondary hyperparathyroidism, and this decrease may play an important role in the pathogenesis of secondary renal hyperparathyroidism.

  3. Sodium metabisulphite, a preservative agent, decreases the heart capillary volume and length, and curcumin, the main component of Curcuma longa, cannot protect it.

    Science.gov (United States)

    Noorafshan, A; Asadi-Golshan, R; Monjezi, S; Karbalay-Doust, S

    2014-01-01

    Sodium metabisulphite is used as an antioxidant agent in many pharmaceutical formulations. It is extensively used as a food preservative and disinfectant. It has been demonstrated that sulphite exposure can affect some organs. Curcumin, the main element of Curcuma longa, has been identified to have multiple protective properties. The present study extends the earlier works to quantitative evaluation of the effects of sulphite and curcumin on the heart structure using stereological methods. In this study, 28 rats were randomly divided into four experimental groups. The rats in groups I to IV received distilled water (group I), sodium metabisulphite (25 mg/ kg/day) (group II), curcumin (100 mg/kg/day) (group III), and sodium metabisulphite+curcumin (group IV), respectively, for 8 weeks. The left ventricle was subjected to stereological methods to estimate the quantitative parameters of the myocardium. A 20 % decrease was observed in the total volume of ventricular tissue in the sulphite-treated animals compared to the distilled water treatment (P preservative food agent, reduced the length and volume of the ventricular capillaries and curcumin could not protect them.

  4. Mechanosensitivity of wild-type and G551D cystic fibrosis transmembrane conductance regulator (CFTR) controls regulatory volume decrease in simple epithelia.

    Science.gov (United States)

    Xie, Changyan; Cao, Xu; Chen, Xibing; Wang, Dong; Zhang, Wei Kevin; Sun, Ying; Hu, Wenbao; Zhou, Zijing; Wang, Yan; Huang, Pingbo

    2016-04-01

    Mutations of cystic fibrosis transmembrane conductance regulator (CFTR), an epithelial ligand-gated anion channel, are associated with the lethal genetic disease cystic fibrosis. The CFTR G551D mutation impairs ATP hydrolysis and thereby makes CFTR refractory to cAMP stimulation. Both wild-type (WT) and G551D CFTR have been implicated in regulatory volume decrease (RVD), but the underlying mechanism remains incompletely understood. Here, we show that the channel activity of both WT and G551D CFTR is directly stimulated by mechanical perturbation induced by cell swelling at the single-channel, cellular, and tissue levels. Hypotonicity activated CFTR single channels in cell-attached membrane patches and WT-CFTR-mediated short-circuit current (Isc) in Calu-3 cells, and this was independent of Ca(2+)and cAMP/PKA signaling. Genetic suppression and ablation but not G551D mutation of CFTR suppressed the hypotonicity- and stretch-inducedIscin Calu-3 cells and mouse duodena. Moreover, ablation but not G551D mutation of the CFTR gene inhibited the RVD of crypts isolated from mouse intestine; more importantly, CFTR-specific blockers markedly suppressed RVD in both WT- and G551D CFTR mice, demonstrating for the first time that the channel activity of both WT and G551D CFTR is required for epithelial RVD. Our findings uncover a previously unrecognized mechanism underlying CFTR involvement in epithelial RVD and suggest that the mechanosensitivity of G551D CFTR might underlie the mild phenotypes resulting from this mutation.-Xie, C., Cao, X., Chen, X, Wang, D., Zhang, W. K., Sun, Y., Hu, W., Zhou, Z., Wang, Y., Huang, P. Mechanosensitivity of wild-type and G551D cystic fibrosis transmembrane conductance regulator (CFTR) controls regulatory volume decrease in simple epithelia.

  5. A combined VBM and DTI study of schizophrenia: bilateral decreased insula volume and cerebral white matter disintegrity corresponding to subinsular white matter projections unlinked to clinical symptomatology.

    Science.gov (United States)

    Onay, Aslıhan; Yapıcı Eser, Hale; Ulaşoğlu Yıldız, Çiğdem; Aslan, Selçuk; Talı, Erhan Turgut

    2017-01-01

    Grey matter and white matter changes within the brain are well defined in schizophrenia. However, most studies focused on either grey matter changes or white matter integrity separately; only in limited number of studies these changes were interpreted in the same frame. In addition, the relationship of these findings with clinical variables is not clearly established. Here, we aimed to investigate the grey matter and white matter changes in schizophrenia patients and exhibit the relation of these imaging findings with clinical variables. A total of 20 schizophrenia patients and 16 matched healthy controls underwent magnetic resonance imaging to investigate the grey matter and white matter alterations that occur in schizophrenia patients using voxel-based morphometry (VBM) and whole brain voxel-wise analysis of diffusion tensor imaging (DTI) parameters with SPM8, respectively. While the preprocessing steps of VBM were performed with the default parameters of VBM8 toolbox, the preprocessing steps of DTI were carried out using FSL. Additionally, VBM results were correlated with clinical variables. Bilateral insula showed decreased grey matter volume in schizophrenia patients compared with healthy controls (P < 0.01). The opposite contrast did not show a significant difference. Psychiatric scores, duration of illness, and age were not correlated with the decreased grey matter volume of insula in schizophrenia patients. DTI analysis revealed a significant increase in mean, radial, and axial diffusivity, mainly of the fibers of bilateral anterior thalamic radiation and superior longitudinal fasciculus with left predominance, which intersected with bilateral subinsular white matter (P < 0.05). Our findings suggest that insula may be the main affected brain region in schizophrenia, which is also well supported by the literature. Our results were independent of disease duration and schizophrenia symptoms. White matter alterations were observed within bilateral anterior

  6. Double diameter boring tool

    Science.gov (United States)

    Ashbaugh, Fred N.; Murry, Kenneth R.

    1988-12-27

    A boring tool and a method of operation are provided for boring two concentric holes of precision diameters and depths in a single operation. The boring tool includes an elongated tool body, a shank for attachment to a standard adjustable boring head which is used on a manual or numerical control milling machine and first and second diametrically opposed cutting edges formed for cutting in opposite directions. The diameter of the elongated tool body is substantially equal to the distance from the first cutting edge tip to the axis of rotation plus the distance from the second cutting edge tip to the axis of rotation. The axis of rotation of the tool is spaced from the tool centerline a distance substantially equal to one-half the distance from the second cutting edge tip to the axis of rotation minus one-half the distance from the first cutting edge tip to the axis of rotation. The method includes the step of inserting the boring tool into the boring head, adjusting the distance between the tool centerline and the tool axis of rotation as described above and boring the two concentric holes.

  7. Influence of tube's diameter on boiling heat transfer performance in small diameter tubes

    Science.gov (United States)

    Gan, Chengjun; Wang, Weicheng; Zhang, Lining

    1998-03-01

    This paper reports the experiments of evaporation study in 6 mm inner copper diameter tubes using HFC-134a, HCFC-22 and CFC-12 as working fluid. The results show that the evaporation heat transfer coefficient increases with the decreasing of inner diameter of tubes. A new concept of non-dimensional tube diameter U is proposed in this paper for correction of the influence of the tube diameter on the evaporation heat transfer coefficient. And further, a convenient empirical correction method is presented.

  8. Influence of Tube‘s Diameter on Boling Heat Transfer Performance in Small Diameter Tubes

    Institute of Scientific and Technical Information of China (English)

    GanChengjun; WangWeicheng; 等

    1998-01-01

    This paper reports the experiments of evaporation study in 6 mm inner copper diameter tubes using HFC-134a,HCFC-22 and CFC-12 as working fluid.The results show that the evaporation heat transfer cofeeicient increasese with the decreasing of inner diameter of tubes,A new concept of nondimensional tube diameter U is proposed in this paper for correction of the influence of the tube diameter on the evaporation heat transfer coefficient.And further,a conveinent empirical correction method is preseted.

  9. Photothermal Therapy Using Gold Nanorods and Near-Infrared Light in a Murine Melanoma Model Increases Survival and Decreases Tumor Volume

    Directory of Open Access Journals (Sweden)

    Mary K. Popp

    2014-01-01

    Full Text Available Photothermal therapy (PTT treatments have shown strong potential in treating tumors through their ability to target destructive heat preferentially to tumor regions. In this paper we demonstrate that PTT in a murine melanoma model using gold nanorods (GNRs and near-infrared (NIR light decreases tumor volume and increases animal survival to an extent that is comparable to the current generation of melanoma drugs. GNRs, in particular, have shown a strong ability to reach ablative temperatures quickly in tumors when exposed to NIR light. The current research tests the efficacy of GNRs PTT in a difficult and fast growing murine melanoma model using a NIR light-emitting diode (LED light source. LED light sources in the NIR spectrum could provide a safer and more practical approach to photothermal therapy than lasers. We also show that the LED light source can effectively and quickly heat in vitro and in vivo models to ablative temperatures when combined with GNRs. We anticipate that this approach could have significant implications for human cancer therapy.

  10. Effect of sodium dodecyl sulfate (SDS) on stress response in the Mediterranean mussel (Mytilus Galloprovincialis): regulatory volume decrease (Rvd) and modulation of biochemical markers related to oxidative stress.

    Science.gov (United States)

    Messina, Concetta Maria; Faggio, Caterina; Laudicella, Vincenzo Alessandro; Sanfilippo, Marilena; Trischitta, Francesca; Santulli, Andrea

    2014-12-01

    In this study the effects of an anionic surfactant, sodium dodecyl sulfate (SDS), are assessed on the Mediterranean mussel (Mytilus galloprovincialis), exposed for 18 days at a concentration ranging from 0.1 mg/l to 1 mg/l. The effects are monitored using biomarkers related to stress response, such as regulatory volume decrease (RVD), and to oxidative stress, such as reactive oxygen species (ROS), endogenous antioxidant systems and Hsp70 levels. The results demonstrate that cells from the digestive gland of M. galloprovincialis, exposed to SDS were not able to perform the RVD owing to osmotic stress. Further, SDS causes oxidative stress in treated organisms, as demonstrated by the increased ROS production, in comparison to the controls (p<0.05). Consequently, two enzymes involved in ROS scavenging, superoxide dismutase (SOD) and catalase (CAT) have higher activities and the proportion of oxidized glutathione (GSSG) is higher in hepatopancreas and mantle of treated animals, compared to untreated animals (p<0.05). Furthermore Hsp70 demonstrates an up-regulation in all the analyzed tissues of exposed animals, attesting the stress status induced by the surfactant with respect to the unexposed animals. The results highlight that SDS, under the tested concentrations, exerts a toxic effect in mussels in which the disruption of the osmotic balance follows the induction of oxidative stress.

  11. Small diameter carbon nanopipettes

    Science.gov (United States)

    Singhal, Riju; Bhattacharyya, Sayan; Orynbayeva, Zulfiya; Vitol, Elina; Friedman, Gary; Gogotsi, Yury

    2010-01-01

    Nanoscale multifunctional carbon probes facilitate cellular studies due to their small size, which makes it possible to interrogate organelles within living cells in a minimally invasive fashion. However, connecting nanotubes to macroscopic devices and constructing an integrated system for the purpose of fluid and electrical signal transfer is challenging, as is often the case with nanoscale components. We describe a non-catalytic chemical vapor deposition based method for batch fabrication of integrated multifunctional carbon nanopipettes (CNPs) with tip diameters much smaller (10-30 nm) than previously reported (200 nm and above) and approaching those observed for multiwalled carbon nanotubes. This eliminates the need for complicated attachment/assembly of nanotubes into nanofluidic devices. Variable tip geometries and structures were obtained by controlled deposition of carbon inside and outside quartz pipettes. We have shown that the capillary length and gas flow rate have a marked effect on the carbon deposition. This gives us a flexible protocol, useful for growing carbon layers of different thicknesses at selective locations on a glass pipette to yield a large variety of cellular probes in bulk quantities. The CNPs possess an open channel for fluid transfer with the carbon deposited inside at 875 °C behaving like an amorphous semiconductor. Vacuum annealing of the CNP tips at temperatures up to 2000 °C yields graphitic carbon structures with an increase in conductivity of two orders of magnitude. Penetration of the integrated carbon nanoprobes into cells was shown to produce minimal Ca2+ signals, fast recovery of basal Ca2+ levels and no adverse activation of the cellular metabolism during interrogation times as long as 0.5-1 h.

  12. Effect of Adsorbent Diameter on the Performance of Adsorption Refrigeration

    Institute of Scientific and Technical Information of China (English)

    黄宏宇; 何兆红; 袁浩然; 小林敬幸; 赵丹丹; 窪田光宏; 郭华芳

    2014-01-01

    Adsorbents are important components in adsorption refrigeration. The diameter of an adsorbent can af-fect the heat and mass transfer of an adsorber. The effect of particle diameter on effective thermal conductivity was investigated. The heat transfer coefficient of the refrigerant and the void rate of the adsorbent layer can also affect the effective thermal conductivity of adsorbents. The performance of mass transfer in the adsorber is better when pressure drop decreases. Pressure drop decreases with increasing permeability. The permeability of the adsorbent layer can be improved with increasing adsorbent diameter. The effect of adsorbent diameter on refrigeration output power was experimentally studied. Output power initially increases and then decreases with increasing diameter under different cycle time conditions. Output power increases with decreasing cycle time under similar diameters.

  13. Implosion dynamics and x-ray generation in small-diameter wire-array Z pinches.

    Science.gov (United States)

    Ivanov, V V; Sotnikov, V I; Kindel, J M; Hakel, P; Mancini, R C; Astanovitskiy, A L; Haboub, A; Altemara, S D; Shevelko, A P; Kazakov, E D; Sasorov, P V

    2009-05-01

    It is known from experiments that the radiated x-ray energy appears to exceed the calculated implosion kinetic energy and Spitzer resistive heating [C. Deeney, Phys. Rev. A 44, 6762 (1991)] but possible mechanisms of the enhanced x-ray production are still being discussed. Enhanced plasma heating in small-diameter wire arrays with decreased calculated kinetic energy was investigated, and a review of experiments with cylindrical arrays of 1-16 mm in diameter on the 1 MA Zebra generator is presented in this paper. The implosion and x-ray generation in cylindrical wire arrays with different diameters were compared to find a transition from a regime where thermalization of the kinetic energy is the prevailing heating mechanism to regimes with other dominant mechanisms of plasma heating. Loads of 3-8 mm in diameter generate the highest x-ray power at the Zebra generator. The x-ray power falls in 1-2 mm loads which can be linked to the lower efficiency of plasma heating with the lack of kinetic energy. The electron temperature and density of the pinches also depend on the array diameter. In small-diameter arrays, 1-3 mm in diameter, ablating plasma accumulates in the inner volume much faster than in loads of 12-16 mm in diameter. Correlated bubblelike implosions were observed with multiframe shadowgraphy. Investigation of energy balance provides evidence for mechanisms of nonkinetic plasma heating in Z pinches. Formation and evolution of bright spots in Z pinches were studied with a time-gated pinhole camera. A comparison of x-ray images with shadowgrams shows that implosion bubbles can initiate bright spots in the pinch. Features of the implosions in small-diameter wire arrays are discussed to identify mechanisms of energy dissipation.

  14. Quantum size effects in the volume plasmon excitation of bismuth nanoparticles investigated by electron energy loss spectroscopy

    Science.gov (United States)

    Wang, Y. W.; Kim, J. S.; Kim, G. H.; Kim, Kwang S.

    2006-04-01

    Quantum size effects in volume plasmon excitation of bismuth nanoparticles with diameters ranging from 5to500nm have been studied by electron energy loss spectroscopy. The Bi nanoparticles were prepared by reducing Bi3+ with sodium borohydride in the presence of poly(vinylpyrroldone). The volume plasmon energy and its peak width increase with decreasing nanoparticle diameter, due to the quantum size effect. For the particles with diameter less than 40nm, the increase of the volume plasmon energy is proportional to the inverse square of the nanoparticle diameter, confirming the semimetal to semiconductor transition in Bi nanoparticles.

  15. Body diameters in 3 - 6 years old children from Plovdiv

    Directory of Open Access Journals (Sweden)

    Tineshev Slavi

    2013-01-01

    Full Text Available The purpose of the research is to analyze the body diameters in 3-6 year old children. The biacromial diameters were taken as well as the two chest diameters, the bicristal and bitrohanterial diameters in 316 children (157 boys and 159 girls 3, 4, 5 and 6 years of age attending kindergarten in Plovdiv. The analysis shows that all diameters, with the exception of the bitrohanterial have higher values in boys. The absolute year's increment of the diameters is greater in girls. The growth velocity of the researched features is greatest at the age of 3-4 and 4-5, decreasing at different rates for the different features at the age of 5-6. The only exception is the sagittal chest diameter in both sexes and the bitrohanterial diameters in girls.

  16. Prefrontal-Parietal White Matter Volumes in Healthy Elderlies Are Decreased in Proportion to the Degree of Cardiovascular Risk and Related to Inhibitory Control Deficits

    Science.gov (United States)

    Santos, Pedro P.; Silveira, Paula S. Da; Souza-Duran, Fabio L.; Tamashiro-Duran, Jaqueline H.; Scazufca, Márcia; Menezes, Paulo R.; Leite, Claudia Da Costa; Lotufo, Paulo A.; Vallada, Homero; Wajngarten, Maurício; De Toledo Ferraz Alves, Tânia C.; Rzezak, Patricia; Busatto, Geraldo F.

    2017-01-01

    Cardiovascular risk (CVR) factors may be associated with poor cognitive functioning in elderlies and impairments in brain structure. Using MRI and voxel-based morphometry (VBM), we assessed regional white matter (WM) volumes in a population-based sample of individuals aged 65–75 years (n = 156), subdivided in three CVR subgroups using the Framingham Risk Score. Cognition was assessed using the Short Cognitive Performance Test. In high-risk subjects, we detected significantly reduced WM volume in the right juxtacortical dorsolateral prefrontal region compared to both low and intermediate CVR subgroups. Findings remained significant after accounting for the presence of the APOEε4 allele. Inhibitory control performance was negatively related to right prefrontal WM volume, proportionally to the degree of CVR. Significantly reduced deep parietal WM was also detected bilaterally in the high CVR subgroup. This is the first large study documenting the topography of CVR-related WM brain volume deficits. The significant association regarding poor response inhibition indicates that prefrontal WM deficits related to CVR are clinically meaningful, since inhibitory control is known to rely on prefrontal integrity. PMID:28184203

  17. Intra-tumour 18F-FDG uptake heterogeneity decreases the reliability on target volume definition with positron emission tomography/computed tomography imaging.

    Science.gov (United States)

    Dong, Xinzhe; Wu, Peipei; Sun, Xiaorong; Li, Wenwu; Wan, Honglin; Yu, Jinming; Xing, Ligang

    2015-06-01

    This study aims to explore whether the intra-tumour (18) F-fluorodeoxyglucose (FDG) uptake heterogeneity affects the reliability of target volume definition with FDG positron emission tomography/computed tomography (PET/CT) imaging for nonsmall cell lung cancer (NSCLC) and squamous cell oesophageal cancer (SCEC). Patients with NSCLC (n = 50) or SCEC (n = 50) who received (18)F-FDG PET/CT scanning before treatments were included in this retrospective study. Intra-tumour FDG uptake heterogeneity was assessed by visual scoring, the coefficient of variation (COV) of the standardised uptake value (SUV) and the image texture feature (entropy). Tumour volumes (gross tumour volume (GTV)) were delineated on the CT images (GTV(CT)), the fused PET/CT images (GTV(PET-CT)) and the PET images, using a threshold at 40% SUV(max) (GTV(PET40%)) or the SUV cut-off value of 2.5 (GTV(PET2.5)). The correlation between the FDG uptake heterogeneity parameters and the differences in tumour volumes among GTV(CT), GTV(PET-CT), GTV(PET40%) and GTV(PET2.5) was analysed. For both NSCLC and SCEC, obvious correlations were found between uptake heterogeneity, SUV or tumour volumes. Three types of heterogeneity parameters were consistent and closely related to each other. Substantial differences between the four methods of GTV definition were found. The differences between the GTV correlated significantly with PET heterogeneity defined with the visual score, the COV or the textural feature-entropy for NSCLC and SCEC. In tumours with a high FDG uptake heterogeneity, a larger GTV delineation difference was found. Advance image segmentation algorithms dealing with tracer uptake heterogeneity should be incorporated into the treatment planning system. © 2015 The Royal Australian and New Zealand College of Radiologists.

  18. Finned Small Diameter Tube Heat Exchanger

    Science.gov (United States)

    Dang, Chaobin; Daiguji, Hirofumi; Hihara, Eiji; Tokunaga, Masahide

    The performance of fined small tube heat exchangers was investigated both experimentally and theoretically. The Inner diameters of tubes were 1.0mm, 2.1mm and 4.0mm. Exchanged heat and pressure drop obtained from numerical simulation agreed well with the experimental ones. Calculation results show that the volume of a 2.0mm tube heat exchanger can be reduced to 33% of that of a 4mm tube heat exchanger with the same capacity. In addition the distribution of two-phase flow in a branching unit was investigated by measuring downstream temperature distribution. The flow distribution in a branching unit strongly affects the exchanged heat.

  19. 闽北天然阔叶林径阶材种结构分析及出材率表的编制%Compilation of Output Structure of Diameter Grade Wood Assortments and Volume Ratio Table for Natural Broad-Leaved Forest Tree Species in North Fujian Province

    Institute of Scientific and Technical Information of China (English)

    李晓景; 江希钿; 庄崇洋; 李小铃

    2012-01-01

    应用闽北天然阔叶林现场造材资料,在分析径阶材种结构规律的基础上,选择适合的方程建立材种出材率模型并编制二元材种出材率表.经检验,该表精度较高,在林业生产上有实用价值.为方便生产中应用,还建立了树高曲线模型,由二元材种出材率袁导出了一元材种出材率表.%The volume ratio model of wood assortment was built by choosing the proper equation, and the two dimension merchantable wood assortment volume yielding rate tables were compiled based on structure analyses of diameter grade wood assortments, with on the spot sample timber data collected from the natural broad-leaved forests in the north Fujian Province. The wood assortment volume yielding rate tables were tested to be with high precision and practicable in forestry production. In order to facilitate the production and application, tree height model was established, and the one dimension merchantable wood assortment volume yielding rate tables were derived from the two dimension tables.

  20. Impacto da embolização arterial do leiomioma uterino no volume uterino, diâmetro do mioma dominante e na função ovariana Impact of the myoma arterial embolization by uterine volume, diameter myoma greater and in the ovarian function

    Directory of Open Access Journals (Sweden)

    André Bernardo

    2011-08-01

    Full Text Available RESUMO OBJETIVO: Avaliar o impacto da embolização arterial de miomas (EAM sobre o volume uterino (VU, na função ovariana. MÉTODOS: Trinta pacientes com leiomioma se submeteram à EAM. Foram realizados exames de USPTV e FSH antes e três meses após a EAM. Foram analisados o VU em cm³, o diâmetro do mioma dominante (DMD em cm e o FSH em UI/mL, expressos por média desvio padrão (DP e submetidos a análise estatística pelo teste não paramétrico de Mann-Whitney. RESULTADOS: Foram incluidos na análise 29 casos. A média do VU pré-EAM foi 402,4 165,9 cm³, DMD pré-EAM 5,9 2,1 cm. O VU pós-EAM foi 258,9 118,6 cm³, DMD pós-EAM foi 4,6 1,8 cm. A média da dosagem de FSH pré-EAM foi 4,9 3,5 UI/mL e pós-EAM foi 5,5 4,7 UI/mL com p=0,5. Houve redução de 35% do VU, de 22% no DMD e a EAM não alterou significativamente os valores de FSH após três meses. CONCLUSÃO: O procedimento diminui significativamente o VU e DMD e, não há aumento significativo dos níveis séricos de FSH, não havendo, portanto, alterações na função ovariana.PURPOSE: To evaluate the impact of uterine artery embolization (UAE on uterine volume (UV, greater myoma diameter (GMD and ovarian function three months after the procedure, by transvaginal pelvic ultrasonography (TVPUS and by the determination of follicle-stimulating hormone (FSH. METHODS: Thirty patients with leiomyomas were submitted to UAE. TVPUS and FSH determination were performed before and three months after UAE. UV was determined in cm³, GMD in cm and FSH in IU/mL. Data are reported as as mean standard deviation (SD and were analyzed statistically by the nonparametric Mann-Whitney test. RESULTS: Twenty-nine patients were analyzed. Before UAE, mean UV was 402.4 165.9 cm³ and GMD was 5.9 2.1 cm. After UAE, mean UV was 258.9 118.6 cm³ and GMD was 4.6 1.8 cm. Mean FSH concentration was 4.9 3.5 IU/mL before UAE and 5.5 4.7 IU/mL after UAE, with p=0.5. There was a 35% reduction of UV and a 22

  1. Decreased Left Caudate Volume Is Associated with Increased Severity of Autistic-Like Symptoms in a Cohort of ADHD Patients and Their Unaffected Siblings

    Science.gov (United States)

    O’Dwyer, Laurence; Tanner, Colby; van Dongen, Eelco V.; Greven, Corina U.; Bralten, Janita; Zwiers, Marcel P.; Franke, Barbara; Heslenfeld, Dirk; Oosterlaan, Jaap; Hoekstra, Pieter J.; Hartman, Catharina A.; Groen, Wouter; Rommelse, Nanda; Buitelaar, Jan K.

    2016-01-01

    Autism spectrum disorder (ASD) symptoms frequently occur in individuals with attention-deficit/hyperactivity disorder (ADHD). While there is evidence that both ADHD and ASD have differential structural brain correlates, knowledge of the structural brain profile of individuals with ADHD with raised ASD symptoms is limited. The presence of ASD-like symptoms was measured by the Children's Social Behavior Questionnaire (CSBQ) in a sample of typically developing controls (n = 154), participants with ADHD (n = 239), and their unaffected siblings (n = 144) between the ages of 8 and 29. Structural magnetic resonance imaging (MRI) correlates of ASD ratings were analysed by studying the relationship between ASD ratings and grey matter volumes using mixed effects models which controlled for ADHD symptom count and total brain volume. ASD ratings were significantly elevated in participants with ADHD relative to controls and unaffected siblings. For the entire group (participants with ADHD, unaffected siblings and TD controls), mixed effect models revealed that the left caudate nucleus volume was negatively correlated with ASD ratings (t = 2.83; P = 0.005). The current findings are consistent with the role of the caudate nucleus in executive function, including the selection of goals based on the evaluation of action outcomes and the use of social reward to update reward representations. There is a specific volumetric profile associated with subclinical ASD-like symptoms in participants with ADHD, unaffected siblings and controls with the caudate nucleus and globus pallidus being of critical importance in predicting the level of ASD-like symptoms in all three groups. PMID:27806078

  2. Characteristics of Angora rabbit fiber using optical fiber diameter analyzer.

    Science.gov (United States)

    Rafat, S A; de Rochambeau, H; Brims, M; Thébault, R G; Deretz, S; Bonnet, M; Allain, D

    2007-11-01

    An experiment was conducted to describe the characteristics of Angora rabbit fiber using optical fiber diameter analyzer (OFDA). A total of 349 fleece samples were collected from 60 French Angora rabbits. Recorded measurements of OFDA were as follows: mean fiber diameter, CV of fiber diameter, comfort factor, spinning fineness, mean fiber curvature, SD of fiber curvature, mean opacity of fibers, percentage of medullated fibers, mean fiber diameter along the length, and SD of fiber diameter along the length. Comfort factor is the percentage of fibers less than or equal to 30 microns. The main effects included in the mixed model were fixed effects of group, harvest season, and age and a random effect of animal. Correlations among total fleece weight, compression, and OFDA measurements were calculated. Mean fiber diameter was lower than the fiber diameter along the length. Mean percentage of medullated fibers was very low and ranged from 0.1 to 7.3%. The mean comfort factor was 97.5% and ranged from 93.3 to 99.8%. The mean fiber curvature was 40.1 degrees/mm. The major changes in Angora fleece characteristics from 8 to 105 wk of age were an increase in fiber diameter, CV of fiber diameter, mean fiber diameter along the length and curvature, and a decrease in compression and comfort factor. The effect of harvest season was significant on some fiber characteristics. Mean fiber diameter and the mean fiber diameter along the length had a positive correlation with total fleece weight. The OFDA methodology is a method to evaluate fiber diameter, CV of fiber diameter, and bristle content through measuring of the comfort factor. However, OFDA is not adapted for measuring opacity or size of the medulla, or both, in Angora wool and needs a new definition or a special calibration. The spinning fineness should be redefined and adapted for Angora rabbits.

  3. Tool electrode wear in electrical discharge of small diameter holes

    Directory of Open Access Journals (Sweden)

    Slătineanu Laurenţiu

    2017-01-01

    Full Text Available In the paper, the problem of obtaining small diameter holes in workpieces made of high speed steel by electrical discharge machining was formulated. A fulfil factorial experiment was designed and materialized, taking into consideration the tool electrode diameter, pulse on time and pulse off time as independent variables. The tool electrode wear was evaluated by means of the decrease of tool electrode mass and length. On the base of experimental results, power type empirical mathematical models were determined. One noticed the higher influence exerted by the too electrode diameter, whose increase determine the decrease of the tool electrode.

  4. Diameters of Triton and Pluto

    Energy Technology Data Exchange (ETDEWEB)

    Morrison, D.; Cruikshank, D.P. (Hawaii Univ., Honolulu (USA). Inst. for Astronomy); Brown, R.H. (Hawaii Univ., Honolulu (USA). Dept. of Physics and Astronomy; Hawaii Univ., Honolulu (USA). Hawaii Inst. of Geophysics)

    1982-12-02

    Upper limits are reported to the thermal IR emission from Triton, the major satellite of Neptune, and Pluto, the outermost planet, that permit significant upper limits to be set on their diameters and also demonstrate that both are high albedo objects. These results exclude the possibility that Triton is the largest planetary satellite and are consistent with the small size of Pluto deduced from other data.

  5. Optimizing the Pipe Diameter of the Pipe Belt Conveyor Based on Discrete Element Method

    Science.gov (United States)

    Guo, Yong-cun; Wang, Shuang; Hu, Kun; Li, De-yong

    2016-03-01

    In order to increase the transport volume of the pipe belt conveyor and reduce lateral pressure of the supporting roller set, this study aims to optimize the pipe diameter of the pipe belt conveyor. A mechanical model of the pipe belt conveyor with six supporting roller sets in the belt bearing section was built based on the infinitesimal method, and the formula for calculating the lateral pressure of each supporting roller was deduced on the basis of reasonable assumption. Simulated analysis was carried out on the operation process of the pipe belt conveyor by using the discrete element method. The result showed that, when the other conditions were certain, as the pipe diameter increased, the average lateral pressure of the supporting roller set increased, with a gradually decreasing increment, which was consistent with the calculated result of the theoretical formula. An optimized pipe diameter under the current conditions was obtained by fitting the curve of the formula for calculating the transport volume of the pipe belt conveyor and its simulation curve. It provided a certain reference value for improving the transport efficiency and prolonging the service life of the pipe belt conveyor.

  6. Arterial diameter during central volume depletion in humans

    DEFF Research Database (Denmark)

    Iversen, Helle Klingenberg; Madsen, P; Matzen, S;

    1995-01-01

    .3) to 2.2 (SEM 0.3) 1.min-1] and heart rate [HR, from 64 (SEM 3) to 100 (SEM 7) beats.min-1], mean arterial pressure (MAP, from 77 (SEM 4) to 89 (SEM 2) mmHg [10.3 (SEM 0.53 to 11.9 (SEM 0.27) kPa]) and total peripheral resistance (TPR, from 19 (SEM 2) to 34 (SEM 4) mmHg.min.1-1 [2.5 (SEM 0.27) to 4.......5 (SEM 0.53) kPa.min.1-1]) increased; but with the appearance of presyncopal symptoms, HR, MAP and TPR were reduced to 65 (SEM 8) beats.min-1, 46 (SEM 4) mmHg [6.1 (SEM 0.53) kPa] and 18 (SEM 3) mmHg.min.1-1 [2.4 (SEM 0.4) kPa.min-1.1-1], respectively (P

  7. Ca2+在鼻咽癌细胞凋亡性容积减小中的作用%Roles of Ca2+ in Apoptotic Volume Decrease in Nasopharyngeal Carcinoma Cells

    Institute of Scientific and Technical Information of China (English)

    向静瑶; 胡代军; 孙利华; 杨林杰; 左婉红; 朱林燕; 陈丽新; 王立伟

    2011-01-01

    Objective To study the role of calcium signaling pathway in apoptotic volume decrease (AVD) in nasopharyngeal carcinoma cells. Methods The apoptotic inducer Cisplatin was used to induce apoptotic volume decrease in poorly differentiated nasopharyngeal carcinoma cells (CNE-2Z cells). The software Q500MC was employed for acquisition of time-lapse images of living cells. Cell volume changes were obtained by analysis of the image analysis software Scion Image. Results Extracellular application of Cisplatin induced a decrease of cell volume. The Cisplatin-induced changes in cell volume were significant 10 min after exposed to bath solution containing Cisplatin. Depletion of calcium from the bath solution or extracellular applications of calcium channel blocker nifedipine delayed the initiation of AVD induced by Cisplatin, but not the appearance of AVD. There was no significant difference in AVD 50 min after applications of Cisplatin between control and cells treated with nifedipine or Ca2+ -free bath solution. Conclusion The inflow of Ca2+ across the cell membrane may play an important role in activation of AVD at the early stage of apoptosis.%目的 探讨钙信号途径在凋亡性细胞容积减小中的作用.方法 用凋亡诱导剂顺铂诱导低分化鼻咽癌CNE-2Z细胞发生凋亡性细胞容积减小(AVD),采用Q500MC软件控制定时拍摄固定视野活细胞图像,Scion Image图像分析软件检测细胞容积变化.结果 细胞外灌流顺铂后细胞体积减小,10min后细胞体积减小差异有统计学意义.去除灌流液中的Ca2+或用钙通道阻断剂Nifedipine阻断钙通道后,延缓顺铂诱导的细胞容积减小的发生,但不能防止细胞缩小过程的出现,50 min后,Nifedipine组和无Ca2+灌流液组与顺铂对照组AVD水平均无差异.结论 细胞外Ca2+内流可能在触发细胞凋亡早期细胞容积减小中起重要作用.

  8. Heritability of retinal vessel diameters and blood pressure

    DEFF Research Database (Denmark)

    Taarnhøj, Nina C B B; Larsen, Michael; Sander, Birgit

    2006-01-01

    PURPOSE: To assess the relative influence of genetic and environmental effects on retinal vessel diameters and blood pressure in healthy adults, as well as the possible genetic connection between these two characteristics. METHODS: In 55 monozygotic and 50 dizygotic same-sex healthy twin pairs......%-80%) for CRAE, 83% (95% CI: 73%-89%) for CRVE, and 61% (95% CI: 44%-73%) for mean arterial blood pressure (MABP). Retinal artery diameter decreased with increasing age and increasing arterial blood pressure. Mean vessel diameters in the population were 165.8 +/- 14.9 microm for CRAE, 246.2 +/- 17.7 microm...... and blood glucose, variations in retinal blood vessel diameters and blood pressure were predominantly attributable to genetic effects. A genetic influence may have a role in individual susceptibility to hypertension and other vascular diseases. The results suggest that retinal vessel diameters...

  9. The truth about laser fiber diameters.

    Science.gov (United States)

    Kronenberg, Peter; Traxer, Olivier

    2014-12-01

    To measure the various diameters of laser fibers from various manufacturers and compare them with the advertised diameter. Fourteen different unused laser fibers from 6 leading manufacturers with advertised diameters of 200, 270, 272, 273, 365, and 400 μm were measured by light microscopy. The outer diameter (including the fiber coating, cladding, and core), cladding diameter (including the cladding and the fiber core), and core diameter were measured. Industry representatives of the manufacturers were interviewed about the diameter of their fibers. For all fibers, the outer and cladding diameters differed significantly from the advertised diameter (P cladding, and core diameters of fibers with equivalent advertised diameters differed by up to 180, 100, and 78 μm, respectively. Some 200-μm fibers had larger outer diameters than the 270- to 273-μm fibers. All packaging material and all laser fibers lacked clear and precise fiber diameter information labels. Of 12 representatives interviewed, 8, 3, and 1 considered the advertised diameter to be the outer, the cladding, and the core diameter, respectively. Representatives within the same company frequently gave different answers. This study suggests that, at present, there is a lack of uniformity between laser fiber manufacturers, and most of the information conveyed to urologists regarding laser fiber diameter may be incorrect. Because fibers larger than the advertised laser fibers are known to influence key interventional parameters, this misinformation can have surgical repercussions. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Heritability of retinal vessel diameters and blood pressure

    DEFF Research Database (Denmark)

    Taarnhøj, Nina C B B; Larsen, Michael; Sander, Birgit

    2006-01-01

    PURPOSE: To assess the relative influence of genetic and environmental effects on retinal vessel diameters and blood pressure in healthy adults, as well as the possible genetic connection between these two characteristics. METHODS: In 55 monozygotic and 50 dizygotic same-sex healthy twin pairs......%-80%) for CRAE, 83% (95% CI: 73%-89%) for CRVE, and 61% (95% CI: 44%-73%) for mean arterial blood pressure (MABP). Retinal artery diameter decreased with increasing age and increasing arterial blood pressure. Mean vessel diameters in the population were 165.8 +/- 14.9 microm for CRAE, 246.2 +/- 17.7 microm...... for CRVE, and 0.67 +/- 0.05 microm for AVR. No significant influence on artery or vein diameters was found for gender, smoking, body mass index (BMI), total cholesterol, fasting blood glucose, or 2-hour oral glucose tolerance test values. CONCLUSIONS: In healthy young adults with normal blood pressure...

  11. The early predictive value of a decrease of metabolic tumor volume in repeated (18)F-FDG PET/CT for recurrence of locally advanced non-small cell lung cancer with concurrent radiochemotherapy.

    Science.gov (United States)

    Huang, Wei; Liu, Bo; Fan, Min; Zhou, Tao; Fu, Zheng; Zhang, Zicheng; Li, Hongsheng; Li, Baosheng

    2015-03-01

    The aim of this study is to investigate the value of [(18)F] fluorodeoxyglucose positron emission tomography/computed tomography ((18)F FDG PET/CT) to predict recurrence of patients with locally advanced non-small cell lung cancer (NSCLC) during the early stage of concurrent chemoradiotherapy (CCRT). A total of 53 stage III NSCLC patients without diabetics or undergoing surgery were enrolled in the prospective study. Those patients were evaluated by FDG PET before and following 40Gy radiotherapy (RT) with a concurrent cisplatin-based heterogeneous chemotherapy regimen. Semiquantitative assessment was used to determine maximum and mean SUVs (SUVmax/SUVmean) and metabolic tumor volume (MTV) of the primary tumor. The prognostic significance of PET/CT parameters and other clinical variables was assessed using Cox regression analyses. The cutoffs of PET/CT parameters which have been determined by the previous study were used to separate the groups with Kaplan-Meier curves. Recurrence rates at 1- and 2-years were 18.9% (10/53) and 50.9% (27/53) for all patients, respectively. Cox regression analysis showed that the only prognostic factor for recurrence was a decrease of MTV. Using the cutoff of 29.7%, a decrease of MTV can separate the patients into 2 groups with Kaplan-Meier curve successfully. The prospective study has reinforced the early predictive value of MTV in repeated (18)F-FDG PET/CT for recurrence in a subgroup of locally advanced NSCLC who underwent CCRT. A decrease of MTV in (18)F-FDG uptake by the primary tumor correlates with higher LRFS. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  12. MWD tool for deep, small diameter boreholes

    Energy Technology Data Exchange (ETDEWEB)

    Buytaert, J.P.R.; Duckworth, A.

    1992-03-17

    This patent describes an apparatus for measuring a drilling parameters while drilling a borehole in an earth formation, wherein the borehole includes a small diameter deep borehole portion and a large diameter upper borehole portion. It includes small diameter drillstring means for drilling the deep borehole portion; sensor means, disposed within the small diameter drillstring means, for measuring a drilling parameter characteristic of the deep portion of the borehole while drilling the deep portion of the borehole and for providing sensor output signals indicative of the measured parameter; an upper drillstring portion extending between the surface of the formation and the small diameter drillstring means, the upper drillstring portion including a large diameter drillstring portion; data transmission means disposed within the large diameter drillstring portion and responsive to the sensor output.

  13. Roles of AQP5/AQP5-G103D in carbamylcholine-induced volume decrease and in reduction of the activation energy for water transport by rat parotid acinar cells.

    Science.gov (United States)

    Satoh, Keitaro; Seo, Yoshiteru; Matsuo, Shinsuke; Karabasil, Mileva Ratko; Matsuki-Fukushima, Miwako; Nakahari, Takashi; Hosoi, Kazuo

    2012-10-01

    In order to assess the contribution of the water channel aquaporin-5 (AQP5) to water transport by salivary gland acinar cells, we measured the cell volume and activation energy (E (a)) of diffusive water permeability in isolated parotid acinar cells obtained from AQP5-G103D mutant and their wild-type rats. Immunohistochemistry showed that there was no change induced by carbamylcholine (CCh; 1 μM) in the AQP5 detected in the acinar cells in the wild-type rat. Acinar cells from mutant rats, producing low levels of AQP5 in the apical membrane, showed a minimal increase in the AQP5 due to the CCh. In the wild-type rat, CCh caused a transient swelling of the acinus, followed by a rapid agonist-induced cell shrinkage, reaching a plateau at 30 s. In the mutant rat, the acinus did not swell by CCh challenge, and the agonist-induced cell shrinkage was delayed by 8 s, reaching a transient minimum at around 1 min, and recovered spontaneously even though CCh was persistently present. In the unstimulated wild-type acinar cells, E (a) was 3.4 ± 0.6 kcal mol(-1) and showed no detectable change after CCh stimulation. In the unstimulated mutant acinar cells, high E (a) value (5.9 ± 0.1 kcal mol(-1)) was detected and showed a minimal decrease after CCh stimulation (5.0 ± 0.3 kcal mol(-1)). These results suggested that AQP5 was the main pathway for water transport in the acinar cells and that it was responsible for the rapid agonist-induced acinar cell shrinkage and also necessary to keep the acinar cell volume reduced during the steady secretion in the wild-type rat.

  14. Maximal aneurysm diameter follow-up is inadequate after endovascular abdominal aortic aneurysm repair

    NARCIS (Netherlands)

    Wever, JJ; Blankensteijn, JD; Mali, WPTM; Eikelboom, BC

    2000-01-01

    Background: follow-up after endovascular abdominal aortic aneurysm repair (EAR) generally consists of serial diameter measurements. A size change after EAR, however, is the consequence of alterations of the excluded aneurysm sac volume. Objective: to assess the agreement between diameter measurement

  15. The early predictive value of a decrease of metabolic tumor volume in repeated {sup 18}F-FDG PET/CT for recurrence of locally advanced non-small cell lung cancer with concurrent radiochemotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Wei, E-mail: weihuang@mcw.com [Department of Radiation Oncology (Chest Section), Shandong' s Key Laboratory of Radiation Oncology, Shandong Cancer Hospital, Shandong Academy of Medical Sciences, 440 Jiyan Road, Jinan 250117 (China); Liu, Bo; Fan, Min [Department of Internal Medicine Oncology, Shandong Cancer Hospital, Shandong Academy of Medical Sciences, Jinan (China); Zhou, Tao [Department of Radiation Oncology (Chest Section), Shandong' s Key Laboratory of Radiation Oncology, Shandong Cancer Hospital, Shandong Academy of Medical Sciences, 440 Jiyan Road, Jinan 250117 (China); Fu, Zheng [PET/CT center, Shandong Cancer Hospital, Shandong Academy of Medical Sciences, Jinan (China); Zhang, Zicheng; Li, Hongsheng [Department of Radiation Oncology (Chest Section), Shandong' s Key Laboratory of Radiation Oncology, Shandong Cancer Hospital, Shandong Academy of Medical Sciences, 440 Jiyan Road, Jinan 250117 (China); Li, Baosheng, E-mail: alvinbird@163.com [Department of Radiation Oncology (Chest Section), Shandong' s Key Laboratory of Radiation Oncology, Shandong Cancer Hospital, Shandong Academy of Medical Sciences, 440 Jiyan Road, Jinan 250117 (China)

    2015-03-15

    Highlights: •The patients underwent the second FDG PET during the early stage of concurrent chemoradiotherapy (CCRT). •To our knowledge, this could be the first study showing that the repeated FDG PET during the early stage of CCRT has added value by being a prognostic factor for recurrence of the locally advanced NSCLC patients. •This is a result of continuous research. •The decrease of MTV was the only significant risk factor for recurrence. -- Abstract: Purpose: The aim of this study is to investigate the value of [{sup 18}F] fluorodeoxyglucose positron emission tomography/computed tomography ({sup 18}F FDG PET/CT) to predict recurrence of patients with locally advanced non-small cell lung cancer (NSCLC) during the early stage of concurrent chemoradiotherapy (CCRT). Methods: A total of 53 stage III NSCLC patients without diabetics or undergoing surgery were enrolled in the prospective study. Those patients were evaluated by FDG PET before and following 40 Gy radiotherapy (RT) with a concurrent cisplatin-based heterogeneous chemotherapy regimen. Semiquantitative assessment was used to determine maximum and mean SUVs (SUVmax/SUVmean) and metabolic tumor volume (MTV) of the primary tumor. The prognostic significance of PET/CT parameters and other clinical variables was assessed using Cox regression analyses. The cutoffs of PET/CT parameters which have been determined by the previous study were used to separate the groups with Kaplan–Meier curves. Results: Recurrence rates at 1- and 2-years were 18.9% (10/53) and 50.9% (27/53) for all patients, respectively. Cox regression analysis showed that the only prognostic factor for recurrence was a decrease of MTV. Using the cutoff of 29.7%, a decrease of MTV can separate the patients into 2 groups with Kaplan–Meier curve successfully. Conclusion: The prospective study has reinforced the early predictive value of MTV in repeated {sup 18}F-FDG PET/CT for recurrence in a subgroup of locally advanced NSCLC who

  16. Catalytic growth of carbon nanotubes with large inner diameters

    Directory of Open Access Journals (Sweden)

    WEI REN ZHONG

    2005-02-01

    Full Text Available Carbon nanotubes (2.4 g/g catalyst, with large inner diameters were successfully synthesized through pyrolysis of methane on a Ni–Cu–Al catalyst by adding sodium carbonate into the carbon nanotubes growth system. The inner diameter of the carbon nanotubes prepared by this method is about 20–60 nm, while their outer diameter is about 40–80 nm. Transmission electron microscopy and X-ray diffraction were employed to investigate the morphology and microstructures of the carbon nanotubes. The analyses showed that these carbon nanotubes have large inner diameters and good graphitization. The addition of sodium carbonate into the reaction system brings about a slight decrease in the methane conversion and the yield of carbon. The experimental results showed that sodium carbonate is a mildly toxic material which influenced the catalytic activity of the Ni–Cu–Al catalyst and resulted in the formation of carbon nanotubes with large inner diameters. The growth mechanism of the carbon nanotubes with large inner diameters is discussed in this paper.

  17. Diameter dependence of thermoelectric power of semiconducting carbon nanotubes

    Science.gov (United States)

    Hung, Nguyen T.; Nugraha, Ahmad R. T.; Hasdeo, Eddwi H.; Dresselhaus, Mildred S.; Saito, Riichiro

    2015-10-01

    We calculate the thermoelectric power (or thermopower) of many semiconducting single wall carbon nanotubes (s-SWNTs) within a diameter range 0.5 -1.5 nm by using the Boltzmann transport formalism combined with an extended tight-binding model. We find that the thermopower of s-SWNTs increases as the tube diameter decreases. For some s-SWNTs with diameters less than 0.6 nm , the thermopower can reach a value larger than 2000 μ V /K at room temperature, which is about 6 to 10 times larger than that found in commonly used thermoelectric materials. The large thermopower values may be attributed to the one dimensionality of the nanotubes and to the presence of large band gaps of the small-diameter s-SWNTs. We derive an analytical formula to reproduce the numerical calculation of the thermopower and we find that the thermopower of a given s-SWNT is directly related with its band gap. The formula also explains the shape of the thermopower as a function of tube diameter, which looks similar to the shape of the so-called Kataura plot of the band gap dependence on tube diameter.

  18. Inhibitory effect of hydrocortisol on regulatory volume decrease in Jurkat cells%氢化可的松抑制Jurkat细胞的调节性体积减小

    Institute of Scientific and Technical Information of China (English)

    康劲松; 姜平; 冯娟; 张海龙; 李志昌; 汤富磊; 范少光; 祝世功; 宋德懋

    2004-01-01

    目的:研究氢化可的松对Jurkat细胞调节性体积减小(regulatory volume decrease,RVD)的影响及可能的机制.方法:通过Motic Images Advanced 3.1软件系统实时监测细胞体积的变化,并通过3H掺入实验观察Jurkat细胞增殖.结果:氢化可的松对Jurkat细胞RVD具有剂量依赖性的抑制作用,在10-4和10-3mol·L-1时可以明显抑制Jurkat细胞的RVD,而在10-9、10-7和10-5mol·L-1时对Jurkat细胞的RVD没有明显影响.钾通道阻断剂奎宁(quinine)亦可以抑制Jurkat细胞的RVD.氢化可的松和奎宁在10-3mol·L-1均可明显抑制Jurkat的增殖(包括自然增殖和Con A诱导增殖).结论:氢化可的松对Jurkat细胞RVD的抑制可能是通过钾通道起作用.

  19. 7 CFR 51.2850 - Diameter.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946... Diameter. Diameter means the greatest dimension measured at right angles to a straight line running from...

  20. 7 CFR 51.712 - Diameter.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946... § 51.712 Diameter. Diameter means the greatest dimension measured at right angles to a line from stem...

  1. 7 CFR 51.651 - Diameter.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946...) Definitions § 51.651 Diameter. Diameter means the greatest dimension measured at right angles to a line from...

  2. Measuring angular diameters of extended sources

    NARCIS (Netherlands)

    van Hoof, PAM

    2000-01-01

    When measuring diameters of partially resolved sources like planetary nebulae, H II regions or galaxies, often a technique called Gaussian deconvolution is used. This technique yields a Gaussian diameter, which subsequently has to be multiplied by a conversion factor to obtain the true angular

  3. Diameter of basalt columns derived from fracture mechanics bifurcation analysis.

    Science.gov (United States)

    Bahr, H-A; Hofmann, M; Weiss, H-J; Bahr, U; Fischer, G; Balke, H

    2009-05-01

    The diameter of columnar joints forming in cooling basalt and drying starch increases with decreasing growth rate. This observation can be reproduced with a linear-elastic three-dimensional fracture mechanics bifurcation analysis, which has been done for a periodic array of hexagonal columnar joints by considering a bifurcation mode compatible with observations on drying starch. In order to be applicable to basalt columns, the analysis has been carried out with simplified stationary temperature fields. The critical diameter differs from the one derived with a two-dimensional model by a mere factor of 1/2. By taking into account the latent heat released at the solidification front, the results agree fairly well with observed column diameters.

  4. Reduced arterial diameter during static exercise in humans

    DEFF Research Database (Denmark)

    Olesen, H L; Mitchell, J H; Friedman, D B

    1995-01-01

    of another limb. Static exercise increased heart rate and mean arterial pressure, which were largest during one-leg knee extension. After exercise heart rate and mean arterial pressure returned to the resting level. No changes were recorded in arterial carbon dioxide tension, and the rate of perceived......In eight subjects luminal diameter of the resting limb radial and dorsalis pedis arteries was determined by high-resolution ultrasound (20 MHz). This measurement was followed during rest and during 2 min of static handgrip or of one-leg knee extension at 30% of maximal voluntary contraction...... exertion was approximately 15 units after both types of exercise. The dorsalis pedis arterial diameter was 1.50 +/- 0.20 mm (mean and SE) and the radial AD 2.45 +/- 0.12 mm. During both types of contractions the luminal diameters decreased approximately 3.5% within the first 30 s (P

  5. Pupil diameter covaries with BOLD activity in human locus coeruleus.

    Science.gov (United States)

    Murphy, Peter R; O'Connell, Redmond G; O'Sullivan, Michael; Robertson, Ian H; Balsters, Joshua H

    2014-08-01

    The locus coeruleus-noradrenergic (LC-NA) neuromodulatory system has been implicated in a broad array of cognitive processes, yet scope for investigating this system's function in humans is currently limited by an absence of reliable non-invasive measures of LC activity. Although pupil diameter has been employed as a proxy measure of LC activity in numerous studies, empirical evidence for a relationship between the two is lacking. In the present study, we sought to rigorously probe the relationship between pupil diameter and BOLD activity localized to the human LC. Simultaneous pupillometry and fMRI revealed a relationship between continuous pupil diameter and BOLD activity in a dorsal pontine cluster overlapping with the LC, as localized via neuromelanin-sensitive structural imaging and an LC atlas. This relationship was present both at rest and during performance of a two-stimulus oddball task, with and without spatial smoothing of the fMRI data, and survived retrospective image correction for physiological noise. Furthermore, the spatial extent of this pupil/LC relationship guided a volume-of-interest analysis in which we provide the first demonstration in humans of a fundamental characteristic of animal LC activity: phasic modulation by oddball stimulus relevance. Taken together, these findings highlight the potential for utilizing pupil diameter to achieve a more comprehensive understanding of the role of the LC-NA system in human cognition.

  6. Failure Diameter of PBX 9502: Simulations with the SURFplus model

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-07-03

    SURFplus is a reactive burn model for high explosives aimed at modelling shock initiation and propagation of detonation waves. It utilizes the SURF model for the fast hot-spot reaction plus a slow reaction for the energy released by carbon clustering. A feature of the SURF model is that there is a partially decoupling between burn rate parameters and detonation wave properties. Previously, parameters for PBX 9502 that control shock ini- tiation had been calibrated to Pop plot data (distance-of-run to detonation as a function of shock pressure initiating the detonation). Here burn rate parameters for the high pres- sure regime are adjusted to t the failure diameter and the limiting detonation speed just above the failure diameter. Simulated results are shown for an uncon ned rate stick when the 9502 diameter is slightly above and slightly below the failure diameter. Just above the failure diameter, in the rest frame of the detonation wave, the front is sonic at the PBX/air interface. As a consequence, the lead shock in the neighborhood of the interface is supported by the detonation pressure in the interior of the explosive rather than the reaction immediately behind the front. In the interior, the sonic point occurs near the end of the fast hot-spot reaction. Consequently, the slow carbon clustering reaction can not a ect the failure diameter. Below the failure diameter, the radial extent of the detonation front decreases starting from the PBX/air interface. That is, the failure starts at the PBX boundary and propagates inward to the axis of the rate stick.

  7. Mixed effect models for predicting breast height diameter from stump diameter of Oriental beech in Göldağ

    Directory of Open Access Journals (Sweden)

    Ilker Ercanli

    2015-06-01

    Full Text Available Diameter at breast height (DBH is the simplest, most common and most important tree dimension in forest inventory and is closely correlated with wood volume, height and biomass. In this study, a number of linear and nonlinear models predicting diameter at breast height from stump diameter were developed and evaluated for Oriental beech (Fagus orientalisLipsky stands located in the forest region of Ayancık, in the northeast of Turkey. A set of 1,501 pairs of diameter at breast height-stump measurements, originating from 70 sample plots of even-aged Oriental beech stands, were used in this study. About 80 % of the otal data (1,160 trees in 55 sample plots was used to fit a number of linear and nonlinear model parameters; the remaining 341 trees in 15 sample plots were randomly reserved for model validation and calibration response. The power model data set was found to produce the most satisfactory fits with the Adjusted Coefficient of Determination, R2adj (0.990, Root Mean Square Error, RMSE (1.25, Akaike’s Information Criterion, AIC (3820.5, Schwarz’s Bayesian Information Criterion, BIC (3837.2, and Absolute Bias (1.25. The nonlinear mixed-effect modeling approach for power model with R2adj(0.993, AIC (3598, BIC (3610.1, Absolute Bias (0.73 and RMSE (1.04 provided much better fitting and precise predictions for DBH from stump diameter than the conventional nonlinear fixed effect model structures for this model. The calibration response including tree DBH and stump diameter measurements of the four largest trees in a calibrated sample plot in calibration produced the highest Bias, -5.31 %, and RMSE, -6.30 %, the greatest reduction percentage.

  8. Evaluation of the splats properties and relation with droplets diameters in atomization process using a De Laval Nozzle

    Energy Technology Data Exchange (ETDEWEB)

    Planche, Marie-Pierre, E-mail: marie-pierre.planche@utbm.fr [LERMPS-UTBM Site de Sevenans, 90010 Belfort, Cedex (France); Khatim, Othmane; Dembinski, Lucas [LERMPS-UTBM Site de Sevenans, 90010 Belfort, Cedex (France); Bailly, Yannick [Institute FEMTO-ST/ENISYS, University of Franche-Comte, UMR CNRS 6174, 90000 Belfort (France); Coddet, Christian [LERMPS-UTBM Site de Sevenans, 90010 Belfort, Cedex (France)

    2013-01-15

    Properties of the powders developed during atomization process are essentially determined by process parameters. Experiments based on splat collection have been performed at different stages of the process evolution. Formation of splat formed as a result of impingement of the melted metallic droplets onto a substrate was studied. Splat characteristics have been determined from image analysis in function of process parameters and time progress. Droplet diameters were measured using laser Coulter analyzer. Direct relationships between splat diameter and droplet diameter were established. The atomization experiments point out the strong influence of two processing parameters (atomizing gas and melt nozzle diameter) on splat characteristics and particle size. It has been observed that increasing atomizing pressure leads to a decrease of mean splat diameter and width of the size distribution. Similar evolution was found for droplet diameter. Moreover, it is clearly shown that increasing melt nozzle diameter induces an increase of both splat diameters and droplet diameters. The results provide a better understanding of the influence of atomization parameters on the size distribution. Highlights: Black-Right-Pointing-Pointer In this study, changes of splat characteristics were examined versus operating parameters. Black-Right-Pointing-Pointer Splat diameter decreases with the increase of atomizing pressure. Black-Right-Pointing-Pointer Splat diameter decreases with the decrease of the melt nozzle diameter. Black-Right-Pointing-Pointer Changes of droplet diameter are in good agreement with those of splat diameter.

  9. Numerical simulation of low-Reynolds number flows past two tandem cylinders of different diameters

    Directory of Open Access Journals (Sweden)

    Yong-tao WANG

    2013-10-01

    Full Text Available The flow past two tandem circular cylinders of different diameters was simulated using the ?nite volume method. The diameter of the downstream main cylinder (D was kept constant, and the diameter of the upstream control cylinder (d varied from 0.1D to D. The studied Reynolds numbers based on the diameter of the downstream main cylinder were 100 and 150. The gap between the control cylinder and the main cylinder (G ranged from 0.1D to 4D. It is concluded that the gap-to-diameter ratio (G/D and the diameter ratio between the two cylinders (d/D have important effects on the drag and lift coef?cients, pressure distributions around the cylinders, vortex shedding frequencies from the two cylinders, and ?ow characteristics.

  10. Impact Structures: What Does Crater Diameter Mean?

    Science.gov (United States)

    Turtle, E. P.; Pierazzo, E.; Collins, G. S.; Osinski, G. R.; Melosh, H. J.; Morgan, J. V.; Reimold, W. U.; Spray, J. G.

    2004-03-01

    Crater diameter is an important parameter in energy scaling and impact simulations. However, disparate types of data make the use of consistent metrics difficult. We suggest a consistent terminology and discuss it in the context of several examples.

  11. Defining a Minimum End Mill Diameter

    Directory of Open Access Journals (Sweden)

    A. E. Dreval'

    2015-01-01

    Full Text Available Industrial observations show that the standard mill designs in many cases do not provide a complete diversity of manufacturing operations, and a lot of enterprises are forced to design and manufacture special (original designs of tools. The information search has revealed a lack of end mill diameter calculations in publications. There is a proposal to calculate the end mill diameter either by empirical formulas [2, 3], or by selection from the tables [4].To estimate a minimum diameter of the end mill to perform the specified manufacturing operations based on the mill body strength the formulas are obtained. The initial data for calculation are the flow sheet of milling operation and properties of processed and tool materials. The end mill is regarded, as a cantilevered beam of the circular cross section having Dс diameter (mill core diameter with overhang Lв from rigid fixing and loaded by the maximum bending force and torque.In deriving the formulas were used the following well-reasoned assumptions based on the analysed sizes of the structural elements of the standard mills: a diameter of mill core is linearly dependent on the mill diameter and the overhang; the 4τ 2 to σ 2 4τ2 ratio is constant and equal to 0.065 for contour milling and 0.17 for slot milling.The formulas for calculating the minimum diameter are as follows:  3 обр в 1 121 1.1  K S L L D m C z    for contour milling;  3 обр в 1 207 1.1  K S L L D m C z    for slot milling.Obtained dependences that allow defining a minimum diameter of the end mill in terms of ensuring its strength can be used to design mills for contour milling with radius transition sections, holes of different diameters in the body parts and other cases when for processing a singlemill is preferable.Using the proposed dependencies for calculating a feed of the maximum tolerable strength is reasonable in designing the mills for slots.Assumptions used in deriving

  12. Unit distances and diameters in Euclidean spaces

    CERN Document Server

    Swanepoel, Konrad J

    2007-01-01

    We show that the maximum number of unit distances or of diameters in a set of n points in d-dimensional Euclidean space is attained only by specific types of Lenz constructions, for all d >= 4 and n sufficiently large, depending on d. As a corollary we determine the exact maximum number of unit distances for all even d >= 6, and the exact maximum number of diameters for all d >= 4, for all $n$ sufficiently large, depending on d.

  13. Shaft Diameter Measurement Using Structured Light Vision

    OpenAIRE

    2015-01-01

    A method for measuring shaft diameters is presented using structured light vision measurement. After calibrating a model of the structured light measurement, a virtual plane is established perpendicular to the measured shaft axis and the image of the light stripe on the shaft is projected to the virtual plane. On the virtual plane, the center of the measured shaft is determined by fitting the projected image under the geometrical constraints of the light stripe, and the shaft diameter is meas...

  14. Appendiceal diameter: CT versus sonographic measurements

    Energy Technology Data Exchange (ETDEWEB)

    Orscheln, Emily S. [University of Cincinnati Medical Center, Department of Radiology, Cincinnati, OH (United States); Trout, Andrew T. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States)

    2016-03-15

    Ultrasound and CT are the dominant imaging modalities for assessment of suspected pediatric appendicitis, and the most commonly applied diagnostic criterion for both modalities is appendiceal diameter. The classically described cut-off diameter for the diagnosis of appendicitis is 6 mm when using either imaging modality. To demonstrate the fallacy of using the same cut-off diameter for both CT and US in the diagnosis of appendicitis. We conducted a retrospective review of patients younger than 18 years who underwent both US and CT of the appendix within 24 h. The shortest transverse dimension of the appendix was measured at the level of the proximal, mid and distal appendix on US and CT images. We compared mean absolute difference in appendiceal diameter between US and CT, using the paired t-test. We reviewed exams of 155 children (58.7% female) with a mean age of 11.3 ± 4.2 years; 38 of the children (24.5%) were diagnosed with appendicitis. The average time interval between US and CT was 7.0 ± 5.4 h. Mean appendiceal diameter measured by CT was significantly larger than that measured by US in cases without appendicitis (5.3 ± 1.0 mm vs. 4.7 ± 1.1 mm, P < 0.0001) and in cases with appendicitis (8.3 ± 2.2 mm vs. 7.0 ± 2.0 mm, P < 0.0001). Mean absolute diameter difference at any location along the appendix was 1.3-1.4 mm in normal appendices and 2 mm in cases of appendicitis. Measured appendiceal diameter differs between US and CT by 1-2 mm, calling into question use of the same diameter cut-off (6 mm) for both modalities for the diagnosis of appendicitis. (orig.)

  15. 左心房容积指数及左心房内径指数对射血分数正常心力衰竭的诊断价值对比分析%Compraison between index left atrium volume and index left atrium diameter of their diagnostic value for heart failure with preserved ejection fraction

    Institute of Scientific and Technical Information of China (English)

    叶茜; 杨昕宇; 朱楠; 何大军

    2012-01-01

    Objective To explore the value of left atrium volume index (LAVI)and left atrium diameter index ( LADI) in diagnosis of heart failure with preserved ejection fraction ( HFPEF). Methods Thirty-live patients with HFPEF and 35 patients with Non-HFPEF recruited from Oct 2010 to Oct 2011 in the second people's hospital of Dazhou were enrolled in this study. A series of parameters including left ventricular ejection fraction (LVEF) , LAVI, LADI, left ventricular mass index (LVMI) , mitral low velocity peak at early diastole ( E) , mitral low velocity peak at the end of diastole (A) , initial mitral low deceleration time ( DT) , mitral ring velocity at early diastole (E') , E/A ratio and E/E'ratio were measured and compared between two groups of patients ( HFPEF and Non-HFPEF). Parameters exhibited significant variations between two groups were tested by Pearson association analysis and ROC curve analysis for their association with HFPEF. Results At the cutting edge of 36 ml/m2 , a remarkable association between LAVI and HFPEF was observed. The specificity, sensitivity and accuracy of LAVI for diagnosing HFPEF were 84%. LADI showed a lesser association with HFPEF at the cutting edge of 2.5 cm/m2 , for which the specificity, sensitivity and accuracy were 65% ,70% and 66% , respectively. Conclusions LAVI might play a role as a potential indicator in the diagnosis of HFPEF.%目的 探讨超声心动图左心房容积指数(LAVI)及左心房内径指数(LADI)对射血分数保存心力衰竭(HFPEF)的诊断价值.方法 选取2010年9月至2011年9月于达州市第二人民医院住院的心力衰竭患者70例,其中HEPEF患者35例,非HEPEF患者35例,分别比较2组患者左心室射血分数(LVEF)、LAVI、LADI、左心室质量指数(LVMI)、舒张早期血流速度(E)、舒张晚期血流速度(A)、早期二尖瓣减速时间(DT)、舒张早期运动速度(E′)、舒张早期血流速度与舒张晚期血流速度比值(E/A)、舒张早期二尖瓣血流速度与

  16. Sonographic Determination of Residual Bladder Volume after Application of Different Cystotomy Closure Techniques in Dogs

    Directory of Open Access Journals (Sweden)

    IU Khan1*, MA Khan2, SG Bokhari2, A Safdar2, M Shoaib1, H Akbar2, S Aslam2, MA Khan2 and A Noor2

    2016-11-01

    Full Text Available Residual urine volume is measured to diagnose various neurogenic and obstructive disorders of the urinary bladder. However, it is hypothesized that cystotomy closure using inverting patterns decreases intraluminal diameter of urinary bladder which consequently reduce residual bladder volume. This study aimed to investigate the ideal suturing style for cystotomy incision closure which would exert the least effect on residual bladder volume. The effect of various suturing styles on residual bladder volume was studied sonographically. Residual Bladder Volume (RBV was calculated by the formula, i.e. RBV=L×W× (DL+DT/2×0.625, where L=longitudinal diameter, W=transverse diameter, DL= depth at longitudinal diameter, DT=depth at transverse diameter. 24 healthy mongrel dogs were selected and randomly divided into four equal groups A, B, C and D (n=6. In groups A, B and C, the cystotomy incision was subsequently closed by two-layered appositional suturing pattern, two-layered inverting pattern and three layers (using a combination of appositional and inverting styles, respectively. Group-D remained as sham-operated Control. The results clearly showed that the three-layered closure technique using a combination of appositional and inverting patterns (Group-C, significantly reduced the bladder volume (P<0.01. Two-layered inverting patterns (Group B, also reduced the bladder volume but not up to a significant level, whereas, the appositional suturing technique (group-A exerted the least effect on residual bladder volume. Conclusively, it was inferred that a two-layered appositional suturing pattern should be preferred for closure of cystotomy incision to avoid significant changes in residual bladder volume.

  17. Incorporating shape constraints in generalized additive modelling of the height-diameter relationship for Norway spruce

    Directory of Open Access Journals (Sweden)

    Natalya Pya

    2016-02-01

    Full Text Available Background: Measurements of tree heights and diameters are essential in forest assessment and modelling. Tree heights are used for estimating timber volume, site index and other important variables related to forest growth and yield, succession and carbon budget models. However, the diameter at breast height (dbh can be more accurately obtained and at lower cost, than total tree height. Hence, generalized height-diameter (h-d models that predict tree height from dbh, age and other covariates are needed. For a more flexible but biologically plausible estimation of covariate effects we use shape constrained generalized additive models as an extension of existing h-d model approaches. We use causal site parameters such as index of aridity to enhance the generality and causality of the models and to enable predictions under projected changeable climatic conditions. Methods: We develop unconstrained generalized additive models (GAM and shape constrained generalized additive models (SCAM for investigating the possible effects of tree-specific parameters such as tree age, relative diameter at breast height, and site-specific parameters such as index of aridity and sum of daily mean temperature during vegetation period, on the h-d relationship of forests in Lower Saxony, Germany. Results: Some of the derived effects, e.g. effects of age, index of aridity and sum of daily mean temperature have significantly non-linear pattern. The need for using SCAM results from the fact that some of the model effects show partially implausible patterns especially at the boundaries of data ranges. The derived model predicts monotonically increasing levels of tree height with increasing age and temperature sum and decreasing aridity and social rank of a tree within a stand. The definition of constraints leads only to marginal or minor decline in the model statistics like AIC. An observed structured spatial trend in tree height is modelled via 2-dimensional surface

  18. Structure optimization of small-diameter polarization-maintaining photonic crystal fiber for mini coil of spaceborne miniature fiber-optic gyroscope.

    Science.gov (United States)

    Song, Ningfang; Cai, Wei; Song, Jingming; Jin, Jing; Wu, Chunxiao

    2015-11-20

    A small-diameter polarization-maintaining photonic crystal fiber (PM-PCF) for mini coils of spaceborne miniature fiber-optic gyroscopes is proposed in this paper. To ensure the strength of the small-diameter PM-PCF, a four-ring air holes structure is adopted. Using the full vector finite element method, dependence studies of modal field distribution, birefringence, and confinement loss on several key structure parameters are numerically investigated. The optimized parameter region is obtained. An optimized PM-PCF is fabricated, which can achieve similar to or even better optical properties than that of commercial PM-PCFs. The coating and cladding diameters of the optimized PM-PCF are 135 μm and 100 μm, respectively. Meanwhile, the optimized small-diameter PM-PCF shows a proof test level of 0.5%. The attenuation of the PM-PCF at 1550 nm is ∼2  dB/km. Typical volume of a mini coil wound with 300 m optimized PM-PCF is 5.9  cm3, which is decreased by ∼60% compared with a commercial PM-PCF coil of the same length. The bias stability of this coil is comparable with that of a conventional PMF coil of comparable length. Thus, the optimized small-diameter PM-PCF is suitable for mini coils of spaceborne miniature fiber-optic gyroscopes.

  19. Collagen fibril diameter and leather strength.

    Science.gov (United States)

    Wells, Hannah C; Edmonds, Richard L; Kirby, Nigel; Hawley, Adrian; Mudie, Stephen T; Haverkamp, Richard G

    2013-11-27

    The main structural component of leather and skin is type I collagen in the form of strong fibrils. Strength is an important property of leather, and the way in which collagen contributes to the strength is not fully understood. Synchrotron-based small angle X-ray scattering (SAXS) is used to measure the collagen fibril diameter of leather from a range of animals, including sheep and cattle, that had a range of tear strengths. SAXS data were fit to a cylinder model. The collagen fibril diameter and tear strength were found to be correlated in bovine leather (r(2) = 0.59; P = 0.009), with stronger leather having thicker fibrils. There was no correlation between orientation index, i.e., fibril alignment, and fibril diameter for this data set. Ovine leather showed no correlation between tear strength and fibril diameter, nor was there a correlation across a selection of other animal leathers. The findings presented here suggest that there may be a different structural motif in skin compared with tendon, particularly ovine skin or leather, in which the diameter of the individual fibrils contributes less to strength than fibril alignment does.

  20. 榆林市榆阳区杨树地径、胸径、树高、材积相关性研究%Relativity of Ground Diameter,DBH,Tree Height & Volume of Poplar in Yuyang District of Yulin City

    Institute of Scientific and Technical Information of China (English)

    申世永; 张彩霞; 吕妮; 艾宇

    2012-01-01

    通过对60株榆林市榆阳区内生长的合作杨(Populus simonii×P.pyramidalis cv.‘Opera8177)’生长情况的调查,结果表明:随着树木生长加粗,胸径、地径基本同步增粗,胸径/地径比值变化很小,数值是0.84倍左右,其范围在0.82~0.86;树高的生长量随树木的生长加粗呈现放缓的规律,随着树木生长加粗,树高/地径比值逐渐变小,地径8 cm时,树高/地径比值是58.92倍,地径48 cm时,树高/地径比值是33.38倍。%Growth of 60 trees of Populus simonii×P.pyramidalis cv.'Opera8177' was investigated in Yuyang district of Yulin city.Result shows that DBH,ground diameter synchronous thicken with the growth of the trees;the ratio between DBH ground diameter changes very little;the value whose range is between 0.82-0.86 is 0.84 times.Growth of tree height appears slow law with the growth of trees;the ratio between tree height ground diameter gradually become smaller with the growth of the trees;the ratio between tree height ground diameter are 58.92 33.38 times while the ground diameter are 8 48 cm,respectively.

  1. Diameter Preserving Surjection on Alternate Matrices

    Institute of Scientific and Technical Information of China (English)

    Li Ping HUANG

    2009-01-01

    Let F be a field with |F| ≥ 3, Km be the set of all m × m (m ≥ 4) alternate matrices over F. The arithmetic distance of A, B ∈ Km is d(A, B) := rank(A- B). If d(A, B) = 2, then A and B are said to be adjacent. The diameter of Km is max{d(A, B) : A, B ∈ Km}. Assume that ψ : Km→ Km is a map. We prove the following are equivalent: (a) ψ is a diameter preserving surjection in both directions, (b) ψ is both an adjacency preserving surjection and a diameter preserving map, (c) ψ is a bijective map which preserves the arithmetic distance.

  2. The truth about small-diameter implants.

    Science.gov (United States)

    Christensen, Gordon J; Child, Paul L

    2010-05-01

    SDIs that are treatment planned correctly, placed and loaded properly, and are within a well-adjusted occlusion, are working in an excellent manner for the patients described in this article. It is time for those practitioners unfamiliar with SDIs and their uses to discontinue their discouragement of this technique. SDIs are easily placed, minimally invasive, and a true service to those patients described. They do not replace conventional diameter implants; however, they are a significant and important augmentation to the original root-form implant concept. There is obvious evidence of the growing acceptance of small-diameter implants by both general practitioners and specialists.

  3. THERMAL EVALUATION OF DIFFERENT DRIFT DIAMETER SIZES

    Energy Technology Data Exchange (ETDEWEB)

    H.M. Wade

    1999-01-04

    The purpose of this calculation is to estimate the thermal response of a repository-emplaced waste package and its corresponding drift wall surface temperature with different drift diameters. The case examined is that of a 21 pressurized water reactor (PWR) uncanistered fuel (UCF) waste package loaded with design basis spent nuclear fuel assemblies. This calculation evaluates a 3.5 meter to 6.5 meter drift diameter range in increments of 1.0 meters. The time-dependent temperatures of interest, as determined by this calculation, are the spent nuclear fuel cladding temperature, the waste package surface temperature, and the drift wall surface temperature.

  4. Shaft Diameter Measurement Using Structured Light Vision.

    Science.gov (United States)

    Liu, Siyuan; Tan, Qingchang; Zhang, Yachao

    2015-08-12

    A method for measuring shaft diameters is presented using structured light vision measurement. After calibrating a model of the structured light measurement, a virtual plane is established perpendicular to the measured shaft axis and the image of the light stripe on the shaft is projected to the virtual plane. On the virtual plane, the center of the measured shaft is determined by fitting the projected image under the geometrical constraints of the light stripe, and the shaft diameter is measured by the determined center and the projected image. Experiments evaluated the measuring accuracy of the method and the effects of some factors on the measurement are analyzed.

  5. Shaft Diameter Measurement Using Structured Light Vision

    Directory of Open Access Journals (Sweden)

    Siyuan Liu

    2015-08-01

    Full Text Available A method for measuring shaft diameters is presented using structured light vision measurement. After calibrating a model of the structured light measurement, a virtual plane is established perpendicular to the measured shaft axis and the image of the light stripe on the shaft is projected to the virtual plane. On the virtual plane, the center of the measured shaft is determined by fitting the projected image under the geometrical constraints of the light stripe, and the shaft diameter is measured by the determined center and the projected image. Experiments evaluated the measuring accuracy of the method and the effects of some factors on the measurement are analyzed.

  6. Effect of conical nanopore diameter on ion current rectification.

    Science.gov (United States)

    Kovarik, Michelle L; Zhou, Kaimeng; Jacobson, Stephen C

    2009-12-10

    Asymmetric nanoscale conduits, such as conical track-etch pores, rectify ion current due to surface charge effects. To date, most data concerning this phenomenon have been obtained for small nanopores with diameters comparable to the electrical double layer thickness. Here, we systematically evaluate rectification for nanopores in poly(ethylene terephthalate) membranes with tip diameters of 10, 35, 85, and 380 nm. Current-voltage behavior is determined for buffer concentrations from 1 mM to 1 M and pHs 3.4 and 6.7. In general, ion current rectification increases with decreasing tip diameter, with decreasing ionic strength, and at higher pH. Surface charge contributes to increased pore conductivities compared to bulk buffer conductivities, though double layer overlap is not necessary for rectification to occur. Interestingly, the 35 nm pore exhibits a maximum rectification ratio for the 0.01 M buffer at pH 6.7, and the 380 nm pores exhibit nearly diodelike current-voltage curves when initially etched and strong rectification after the ion current has stabilized.

  7. Forecasting Fruit Diameter of ‘Fuji’Apples (Malus pumila Mill )at Harvest During Early Growing Season

    Institute of Scientific and Technical Information of China (English)

    SONG Guo-qing; YU Ke-shun; LI Shao-hua; LIU Guo-jie; MENG Zhao-qing; ZHU Jun

    2002-01-01

    The fruit growth evolution on 35 tagged‘Fuji'apple trees was studied in three successive growing seasons from 1994 to 1996 to explore a new method for forecasting the fruit diameter at harvest during early growing season. Daily fruit growth rate (DFGR) (based on fruit diameter, fruit dry weight, fruit fresh weight, or fruit volume) during the early growing season, 30 - 50 d after full bloom (DAFB), or during midgrowing season (60 - 120 DAFB), displayed a strong positive linear correlation with the fruit diameter at harvest, and the correlation between the fruit diameter at harvest and DFGR during early and mid-growing season was much better than that between the fruit diameter at harvest and either fruit diameter at a given time or the relative growth rate during early or mid-growing season. The fruit diameters obtained in the field were compared with the mean fruit diameters estimated based on different criteria, such as DFGRs (based on fruit diameter, fruit dry weight, fruit fresh weight, or fruit volume) during early and mid-growing season, and fruit diameter at 120 DAFB. Results showed that daily growth rate of fruit diameter during 30 - 50 DAFB was the best criterion for forecasting fruit diameter at harvest. There was no significant difference in mean fruit diameter between the value measured in the field at harvest and that estimated based on the daily growth rate of fruit diameter during 30 - 50 DAFB (equations for forecasting: y = 153. 571 x + 73. 492) either for the individual trees or for different vigor groups of trees. Daily growth rate of fruit diameter during 30 - 50 DAFB can be used as the basis for forecasting fruit diameter at harvest.

  8. Axonal diameter and density estimated with 7-Tesla hybrid diffusion imaging in transgenic Alzheimer rats

    Science.gov (United States)

    Daianu, Madelaine; Jacobs, Russell E.; Town, Terrence; Thompson, Paul M.

    2016-03-01

    Diffusion-weighted MR imaging (DWI) is a powerful tool to study brain tissue microstructure. DWI is sensitive to subtle changes in the white matter (WM), and can provide insight into abnormal brain changes in diseases such as Alzheimer's disease (AD). In this study, we used 7-Tesla hybrid diffusion imaging (HYDI) to scan 3 transgenic rats (line TgF344-AD; that model the full clinico-pathological spectrum of the human disease) ex vivo at 10, 15 and 24 months. We acquired 300 DWI volumes across 5 q-sampling shells (b=1000, 3000, 4000, 8000, 12000 s/mm2). From the top three b-value shells with highest signal-to-noise ratios, we reconstructed markers of WM disease, including indices of axon density and diameter in the corpus callosum (CC) - directly quantifying processes that occur in AD. As expected, apparent anisotropy progressively decreased with age; there were also decreases in the intra- and extra-axonal MR signal along axons. Axonal diameters were larger in segments of the CC (splenium and body, but not genu), possibly indicating neuritic dystrophy - characterized by enlarged axons and dendrites as previously observed at the ultrastructural level (see Cohen et al., J. Neurosci. 2013). This was further supported by increases in MR signals trapped in glial cells, CSF and possibly other small compartments in WM structures. Finally, tractography detected fewer fibers in the CC at 10 versus 24 months of age. These novel findings offer great potential to provide technical and scientific insight into the biology of brain disease.

  9. Relationship between retinal vessel diameters and retinopathy in the Inter99 Eye Study

    DEFF Research Database (Denmark)

    Drobnjak, Dragana; Munch, Inger Christine; Glümer, Charlotte

    2017-01-01

    .001), and decreased with higher HDL cholesterol (p  diabetes, but not in participants without diabetes......© 2017 The Authors Purpose To examine the association between retinal vessel diameters and retinopathy in participants with and without type 2 diabetes in a Danish population-based cohort. Methods The study included 878 persons aged 30 to 60 years from the Inter99 Eye Study. Retinopathy was defined...... as a presence of one or more retinal hemorrhages or one or more microaneurysms. Vessel diameters were expressed as central retinal artery equivalent diameter (CRAE) and central retinal vein equivalent diameter (CRVE). Multiple linear regression analyses were performed. Results Among participants with diabetes...

  10. Numerical Analysis of Large Diameter Butterfly Valve

    Science.gov (United States)

    Youngchul, Park; Xueguan, Song

    In this paper, a butterfly valve with the diameter of 1,800 mm was studied. Three-dimensional numerical technique by using commercial code CFX were conducted to observe the flow patterns and to measure flow coefficient, hydrodynamic torque coefficient and so on, when the large butterfly valve operated with various angles and uniform incoming velocity.

  11. Photoacoustic determination of blood vessel diameter.

    NARCIS (Netherlands)

    Kolkman, R.G.; Klaessens, J.H.G.M.; Hondebrink, E.; Hopman, J.C.W.; Mul, F.F. de; Steenbergen, W.; Thijssen, J.M.; Leeuwen, T.G. van

    2004-01-01

    A double-ring sensor was applied in photoacoustic tomographic imaging of artificial blood vessels as well as blood vessels in a rabbit ear. The peak-to-peak time (tau(pp)) of the laser (1064 nm) induced pressure transient was used to estimate the axial vessel diameter. Comparison with the actual ves

  12. Reduced artery diameters in Klinefelter syndrome.

    Science.gov (United States)

    Foresta, C; Caretta, N; Palego, P; Ferlin, A; Zuccarello, D; Lenzi, A; Selice, R

    2012-10-01

    Various epidemiological studies in relatively large cohorts of patients with Klinefelter syndrome (KS) described the increased morbidity and mortality in these subjects. Our aim was to study the structure and function of arteries in different districts to investigate in these subjects possible alterations. A total of 92 patients having non-mosaic KS, diagnosed in Centre for Human Reproduction Pathology at the University of Padova, and 50 age-matched healthy male controls were studied. Klinefelter syndrome subjects and controls evaluation included complete medical history, physical examination, measurement of concentrations of the reproductive hormones, lipidic and glycidic metabolism, AR function and sensitivity, ultrasound examinations (diameters, carotid intima-media thickness and brachial flow-mediated dilation) of brachial, common carotid and common femoral artery and abdominal aorta. Klinefelter syndrome patients showed significantly reduced artery diameters in all districts evaluated. On the contrary no statistically significant difference was found in cIMT and brachial FMD values between KS patients and controls. Furthermore, we found no statistically significant correlation of artery diameters with reproductive hormones, metabolic parameters, anthropometric measures and weighted CAG repeats. To our knowledge, this is the first study finding a reduced artery diameter in several districts in KS patients compared with that of normal male subjects and overlapping to that of female subjects. We have not an explanation for this phenomenon, even if a possible involvement of genes controlling the development of vascular system might be hypothesized, and further research is required to verify this hypothesis.

  13. Height-diameter model for black locust, Anatolian black pine and Taurus cedar tree species in Lakes Region

    OpenAIRE

    ÇATAL, Yılmaz

    2012-01-01

    The height of a tree is important for assessing tree volume and site index. Diameter of breast height-tree height releation equations are often used to predict the mean tree height for trees in case only diameter at breast height is measured. This study aim describes between the tree heights with diameter of breast height relationships for artificially grown black locust (Robinia pseudoacacia L.), Anatolian black pine (Pinus nigra Arnold. subsp. pallasiana (Lamb.) Holmboe) and Taurus cedar (C...

  14. Effect of hydrofluoric acid (HF) concentration to pores size diameter of silicon membrane.

    Science.gov (United States)

    Burham, Norhafizah; Hamzah, Azrul Azlan; Majlis, Burhanuddin Yeop

    2014-01-01

    This paper studies parameters which affect the pore size diameter of a silicon membrane. Electrochemical etching is performed in characterise the parameter involved in this process. The parameter has been studied is volume ratio of hydrofluoric acid (HF) and ethanol as an electrolyte aqueous for electrochemical etch. This electrolyte aqueous solution has been mixed between HF and ethanol with volume ratio 3:7, 5:5, 7:3 and 9:1. As a result, the higher volume of HF in this electrolyte gives the smallest pore size diameter compared to the lower volume of HF. These samples have been dipped into HF and ethanol electrolyte aqueous with supplied 25 mA/cm2 current density for 20, 30, 40, and 50 minutes. The samples will inspect under Scanning Electron Microscope (SEM) to execute the pore formations on silicon membrane surface.

  15. Empirical processes with bounded \\psi_1 diameter

    CERN Document Server

    Mendelson, Shahar

    2010-01-01

    We study the empirical process indexed by F^2=\\{f^2 : f \\in F\\}, where F is a class of mean-zero functions on a probability space. We present a sharp bound on the supremum of that process which depends on the \\psi_1 diameter of the class F (rather than on the \\psi_2 one) and on the complexity parameter \\gamma_2(F,\\psi_2). In addition, we present optimal bounds on the random diameters \\sup_{f \\in F} \\max_{|I|=m} (\\sum_{i \\in I} f^2(X_i))^{1/2} using the same parameters. As applications, we extend several well known results in Asymptotic Geometric Analysis to any isotropic, log-concave ensemble on R^n.

  16. Transfinite diameter of Bernstein sets in

    Directory of Open Access Journals (Sweden)

    Bialas-Cież Leokadia

    2002-01-01

    Full Text Available Let be a compact set in satisfying the following generalized Bernstein inequality: for each such that , for each polynomial of degree where is a constant independent of and , is an infinite set of natural numbers that is also independent of and . We give an estimate for the transfinite diameter of the set : For satisfying the usual Bernstein inequality (i.e., , we prove that

  17. New Large Diameter RF Complex Plasma Device

    Science.gov (United States)

    Meyer, John; Nosenko, Volodymyr; Thomas, Hubertus

    2016-10-01

    The Complex Plasma Research Group at the German Aerospace Center (DLR) in Oberpfaffenhofen has built a new large diameter rf plasma setup for dusty plasma experiments. The vacuum chamber is a stainless steel cylinder 0.90 m in diameter and 0.34 m in height with ports for viewing and measurement. A 0.85 m diameter plate in about the center serves as a powered electrode (13.56 MHz) with the chamber walls as the ground. It is pumped on by one of two Oerlikon turbo pumps with a pumping rate of 1100 l/s or 270 l/s. Argon gas is admitted into the chamber by an MKS mass flow meter and pumping is regulated by a butterfly valve to set pressure for experiments. A manual dropper is used to insert dust into the plasma. The dust is illuminated horizontally by a 660 nm 100 mW laser sheet and viewed from above by a Photron FASTCAM 1024 PCI camera. A vertical laser sheet of 635 nm will be used for side imaging. So far, single-layer plasma crystals of up to 15000 particles have been suspended. The particle velocity fluctuation spectra were measured and from these, the particle charge and screening length were calculated. Future experiments will explore the system-size dependence of the plasma crystal properties.

  18. 29 mm Diameter Test Target Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Woloshun, Keith Albert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Olivas, Eric Richard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Naranjo, Angela Carol [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Romero, Frank Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-15

    The Northstar target for Mo99 production is made up of Mo100 disks in a stack separated by coolant gaps for helium flow. A number of targets have been tested at ANL for both production of Mo99 and for thermal-hydraulic performance. These have all been with a 12 mm diameter target, even while the production goals have increased the diameter to now 29 mm. A 29 mm diameter target has been designed that is consistent with the ANL beam capabilities and the capabilities of the helium circulation system currently in use at ANL. This target is designed for 500 μA at 35 MeV electrons. While the plant design calls for 42 MeV, the chosen design point is more favorable and higher power given the limits of the ANL accelerator. The intended beam spot size is 12 mm FWHM, but the thermal analysis presented herein conservatively assumed a 10 mm FWHM beam, which results in a 44% higher beam current density at beam center.

  19. Irrigation effects on diameter growth of 2-year-old Paulownia tomentosa saplings

    Institute of Scientific and Technical Information of China (English)

    Javad Eshaghi Rad; Seyed Rostam Mousavi Mirkala

    2015-01-01

    Species of Paulownia are fast-growing trees that are planted in many countries in green spaces and agroforestry systems. We studied the influence of irrigation on the diameter growth of 2-year-old Paulownia tomentosa saplings planted in 3 m × 3 m grids at Nazlou Campus of Urmia University, Iran. Completely randomized experi-mental design was used with four irrigation amount, viz. 10, 15, 20 and 25 L, and three irrigation intervals, viz. 3-and 6-days, in 8 replications. During the growth season, we measured collar diameters of all saplings at the end of each month. Diameter growth declined with reduced irrigation amount and increased irrigation interval. The lowest average diameter growth (9 mm) was recorded for 10 L water at 6-day intervals and maximum average diameter growth (28.7 mm) was recorded for 25 L volume at 3-day intervals. The latter treatment resulted in significantly greater diameter growth than any other treatment (except 20 L at 3-day intervals). More than 80% of diameter growth was achieved in the first 3 months. Therefore, it is essential to irrigate with 25 L of water at 3-day intervals during the first three growth months to achieve maximum diameter growth for 2-year-old P. tomentosa saplings.

  20. Effects of Pupil Diameter on Light Detection and Temporal Modulation

    Institute of Scientific and Technical Information of China (English)

    Rachel S Li; Andrew W Siu; Johnny C Liyu; Elice C Chan

    2003-01-01

    Purpose: This study compared the effects of pupil variation on light detection and temporal modulation across the central visual field.Methods:Light detection sensitivity (LDS) and low flickering frequency (6Hz) temporal modulation sensitivity (TMS) of 20 young subjects were measured from the central visual field of the right eyes using an automated perimeter (Medmont M600). The measurements were taken under 3 artificial pupils, I.e. 3 mm, 4.3 mm and 6 mm diameters.The sensitivities were grouped and averaged for different retinal eccentricities(3°, 6°, 10° and 15°).Results:TMS and LDS were reduced with increasing retinal eccentricities( P < 0.001)and decreasing pupil diameters( P < 0.001). TMS collected from all pupil diameters were significantly different from each other( P < 0.001). Similarly, LDS under 3 mm pupil was statistically different from those of 4.3 mm and 6 mm(P < 0.003). Comparison of the hills of vision showed that pupil variation resulted in significantly different slopes (P=0.001).The slopes were also found to be significantly different between TMS and LDS (P=0.012).Conclusions: The data showed that dilated pupil resulted in significantly higher sensitivities than those of smaller pupil for both visual functions. The difference in the slopes of hills of vision also suggested that the variation in retinal illumination affected the visual responses differently at various retinal eccentricitities for TMS and LDS.

  1. Normal reference values for vertebral artery flow volume by color Doppler sonography in Korean adults

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Hyun Sook; Cha, Jang Gyu; Park, Seong Jin; Joh, Joon Hee; Park, Jai Soung; Kim, Dae Ho; Lee, Hae Kyung; Ahn, Hyun Cheol [Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of)

    2003-09-15

    Vertebrobasilar ischemia has been attributed to a reduction of net vertebral artery flow volume. This study was to establish the reference values for the flow volume of the vertebral artery using color Doppler sonography in the normal Korea adults. Thirty five normal Korea adults without any underlying disease including hypertension, hyperlipidemia, diabetes, heart disease, obesity (body mas index>30), or carotid artery stenosis was included. There were 17 males and 18 females, age ranged from 20 to 53 years (average=32.86 years). Flow velocities and vessel diameters were recorded in the intertransverse (V2) segment, usually at C5-6 level, bilaterally. The flow volume (Q) was calculated. (Q=time averaged mean velocity x cross sectional area of vessel) A lower Flow velocity and smaller vessel diameter were measured on the right side compared to those of the left side, resulting in a lower flow volume. The calculated flow volumes using the equation were 77.0 +- 39.7 ml/min for the right side and 127.6 +- 71.0 ml/min for the left side (p=0.0001) while the net vertebral artery flow volume was 204.6 +- 81.8 ml/min. Decrease in the vertebral artery flow volume was statistically significant with advanced age. (r=-0.36, p=0.032). Vertebral artery blood flow volume was 191.20 +- 59.19 ml/min in male, and 217.28 +- 98.67 ml/min in female (p=0.6). The normal range for the net vertebral artery flow volume defined by the 5th to 95th percentiles was between 110.06 and 364.1 ml/min. The normal range for the net vertebral artery flow volume was between 110.06 and 364.1 ml/min. Vertebral artery flow volume decreased with the increase of age. However, gender did not affect the blood flow volume.

  2. Theoretical Study of the Effect of Multi-Diameter Distribution on the Mie Scattering Characteristics of Milk Fat

    Institute of Scientific and Technical Information of China (English)

    Jinying Yin∗; Siqi Zhang; Hongyan Yang; Zhen Zhou

    2015-01-01

    To correct the light scattering property parameters of milk fat for improving the detection accuracy, the Mie⁃theory was used to establish a predictive model for light scattering properties of milk fat globule with multi⁃diameter distributions, by means of Monte Carlo approach to simulate actual multi⁃diameter size distribution of milk fat globule in milk fat solution. Scattering coefficient and absorption coefficient of multi⁃diameter distribution milk fat particles were calculated by simulating the particles size distribution in milk fat solution. And the light scattering properties of multi⁃diameter distribution was compared with that of volume mean diameter, Sauter mean diameter and numerical mean diameter in milk fat solution. Theoretical simulation results indicate that the scattering coefficient and absorption coefficient of milk fat particles are determined by the particle size distribution in milk fat solution. There is a distinct difference in scattering characteristics between the milk fat particles with multi⁃diameter distribution and that with mean diameters. Compared to that with multi⁃diameter distribution, the scattering coefficient of the milk fat particles with mean diameter has a maximum mean deviation of 9 042 m-1 . The particle size distribution is not completely determined by the mean diameters. The dependence of the light scattering properties on the particle size distribution should be considered into the model and simulation. Therefore, it is found that the particle size distribution in milk fat solution is an essential and critical factor to significantly improve the detection accuracy of milk fat content.

  3. Retinal vessel diameter changes induced by transient high perfusion pressure

    Institute of Scientific and Technical Information of China (English)

    Yin-Ying; Zhao; Ping-Jun; Chang; Fang; Yu; Yun-E; Zhao

    2014-01-01

    ·AIM: To investigate the effects of transient high perfusion pressure on the retinal vessel diameter and retinal ganglion cells.·METHODS: The animals were divided into four groups according to different infusion pressure and infusion time(60 mm Hg-3min, 60 mm Hg-5min, 100 mm Hg-3min, 100 mm Hg-5min). Each group consisted of six rabbits. The left eye was used as the experimental eye and the right as a control. Retinal vascular diameters were evaluated before, during infusion, immediately after infusion, 5min, 10 min and 30 min after infusion based on the fundus photographs. Blood pressure was monitored during infusion. The eyes were removed after 24 h.Damage to retinal ganglion cell(RGC) was analyzed by histology.·RESULTS: Retina became whiten and papilla optic was pale during perfusion. Measurements showed significant decrease in retinal artery and vein diameter during perfusion in all of the four groups at the proximal of the edge of the optic disc. The changes were significant in the 100 mm Hg-3min group and 100 mm Hg-5min group compared with 60 mm Hg-3min group(P 1=0.025, P 2=0.000).The diameters in all the groups recovered completely after 30 min of reperfusion. The number of RGC)showed no significant changes at the IOP in 100 mm Hg with5 min compared with contralateral untreated eye(P >0.05).·CONCLUSION: Transient fluctuations during infusion lead to temporal changes of retinal vessels, which could affect the retinal blood circulation. The RGCs were not affected by this transient fluctuation. Further studies are necessary to evaluate the effect of pressure during realtime phacoemusification on retinal blood circulation.

  4. Bloch-wave engineered submicron-diameter quantum-dot micropillars for cavity QED experiments

    DEFF Research Database (Denmark)

    Gregersen, Niels; Lermer, Matthias; Reitzenstein, Stephan;

    2013-01-01

    The semiconductor micropillar is attractive for cavity QED experiments. For strong coupling, the figure of merit is proportional to Q/√V, and a design combining a high Q and a low mode volume V is thus desired. However, for the standard submicron diameter design, poor mode matching between...

  5. High-dose desloratadine decreases wheal volume and improves cold provocation thresholds compared with standard-dose treatment in patients with acquired cold urticaria: a randomized, placebo-controlled, crossover study.

    Science.gov (United States)

    Siebenhaar, Frank; Degener, Franziska; Zuberbier, Torsten; Martus, Peter; Maurer, Marcus

    2009-03-01

    Increased dosing of nonsedating antihistamines is recommended by the current European Academy of Allergology and Clinical Immunology/Global Allergy and Asthma European Network/European Dermatology Forum guidelines on patients with acquired cold urticaria (ACU) who do not respond satisfactorily to the standard dose. Prospective data supporting this recommendation are scant. We sought to assess the effects of 5 and 20 mg of desloratadine and placebo on cold-induced urticarial reactions in patients with ACU. In this prospective, randomized, double-blind, 3-way crossover trial, patients with ACU (n = 30) received placebo, 5 mg of desloratadine, and 20 mg of desloratadine every day each for 7 days separated by 14-day washout periods. At the end of each treatment, patients underwent cold provocation with the TempTest 2.0/2.1 system, and urticarial reactions were assessed by using digital 3-dimensional time-lapse photography and thermography; the critical temperature threshold (CTT) and critical stimulation time threshold (CSTT) were measured. Adverse events (AEs) reported during the study were assessed. Compared with placebo, 7 days of desloratadine at 5 and 20 mg/d significantly reduced the volume of cold-induced wheals and areas of hyperthermic skin and improved CTT and CSTT results. Desloratadine at 20 mg/d significantly reduced cold-induced wheal volume and CTT and CSTT values versus desloratadine at 5 mg/d. Desloratadine was well tolerated, with no increased rate of somnolence or other AEs with 20 mg of desloratadine. Desloratadine at standard and high doses significantly improved objective signs of ACU provoked by cold exposure. Desloratadine at 4 times the standard dose significantly reduced ACU lesion severity versus 5 mg of desloratadine without an increase in AEs. This study supports current guidelines that increased desloratadine dosing might benefit patients with urticaria who do not respond to standard doses.

  6. Retrobulbar diameter of optic nerve in glaucoma

    Directory of Open Access Journals (Sweden)

    Stefanović Ivan

    2009-01-01

    Full Text Available Introduction. The ultrasound diagnostics of the optic nerve includes the analysis of the optic nerve disc (PNO and measuring of its retrobulbar diameter. With B-scan, by Schraeder's method, it is possible to measure very precisely the optic nerve, the pial diameter, the normal values for the pial diameter being 2.8-4.1 mm. In glaucoma, the disease that is most frequently associated with higher intraocular pressure, there comes the destruction of nerve fibres, which can be visualized as the excavation of the optic nerve disc. Objective. In this paper, we were interested in finding whether in glaucoma, and in what phase of the disease, the optic nerve starts growing thinner. Aware of many forms of this very complex disease, we were interested in knowing if the visualization of excavation on the optic nerve disc is related to diminishing of the pial diameter of the retrobulbar nerve part. Methods. There were treated the patients who had already had the diagnosis of glaucoma and the visualized excavation of the optic disc of various dimensions. Echographically, there was measured the thickness of the retrobulbar part of the optic nerve and the finding compared in relation to the excavation of the optic disc. Results. In all eyes with glaucoma, a normal size of the retrobulbar part of the optic nerve was measured, ranging from 3.01 to 3.91 mm with the median of 3.36 mm. Also, by testing the correlation between the thickness of the optic nerve and the excavation of the PNO, by Pearson test, we found that there was no correlation between these two parameters (r=0.109; p>0.05. Conclusion. In the patients with glaucoma, the retrobulbar part of the optic nerve is not thinner (it has normal values, even not in the cases with a totally excavated optic disc. There is no connection between the size of the PNO excavation and the thickness of the retrobulbar part of the optic nerve.

  7. Risk of dislocation using large- vs. small-diameter femoral heads in total hip arthroplasty

    Directory of Open Access Journals (Sweden)

    Plate Johannes F

    2012-10-01

    Full Text Available Abstract Background Dislocation remains a difficult problem in total hip arthroplasty. Large-diameter femoral heads may lower the incidence of dislocation by enhancing the jump distance and decreasing impingement, but their performance against small-diameter heads has not been assessed. This study compared the mid-term radiographic and functional outcomes of two matched cohorts of patients undergoing total hip arthroplasty who had a high pre-operative risk for dislocation and who received either small-diameter (26- or 28-millimeters or large-diameter (≥36-millimeters femoral heads. Methods All patients who received large-diameter heads (≥36-millimeter between 2002 and 2005, and who had pre-operative risk factors for dislocation, were identified in the institution’s joint registry. Forty-one patients (52 hips who received large-diameter heads were identified, and these patients were matched to 48 patients (52 hips in the registry who received small-diameter femoral heads. Results At mean final follow-up of 62 months (range, 49 to 101 months, both groups achieved excellent functional outcomes as measured by Harris Hip scores, with slightly better final scores in the large-diameter group (90 vs. 83 points. No patient showed any radiographic signs of loosening. No patient dislocated in the large-diameter femoral head group; the smaller-diameter group had a greater rate of dislocation (3.8%, 2 out of 52. Conclusions Large-diameter femoral head articulations may reduce dislocation rates in patients who have a high pre-operative risk for dislocation while providing the same functional improvements and safety as small-diameter bearings.

  8. On-chip measurements of Brownian relaxation of magnetic beads with diameters from 10 nm to 250 nm

    DEFF Research Database (Denmark)

    Østerberg, Frederik Westergaard; Rizzi, Giovanni; Hansen, Mikkel Fougt

    2013-01-01

    We demonstrate the use of planar Hall effect magnetoresistive sensors for AC susceptibility measurements of magnetic beads with frequencies ranging from DC to 1 MHz. This wide frequency range allows for measuring Brownian relaxation of magnetic beads with diameters ranging from 10 nm to 250 nm...... to sedimentation, magnetic trapping, and signal per bead. Among the investigated beads, we conclude that the beads with a nominal diameter of 80 nm are best suited for future on-chip volume-based biosensing experiments using planar Hall effect sensors........ Brownian relaxation is measured for six different magnetic bead types and their hydrodynamic diameters are determined. The hydrodynamic diameters are found to be within 40% of the nominal bead diameters. We discuss the applicability of the different bead types for volume-based biosensing with respect...

  9. Analysis of concentration characteristics in ultrasonic atomization by droplet diameter distribution.

    Science.gov (United States)

    Yasuda, Keiji; Bando, Yoshiyuki; Yamaguchi, Soyoko; Nakamura, Masaaki; Oda, Akiyoshi; Kawase, Yasuhito

    2005-01-01

    The droplet diameter distribution and concentration characteristics in ultrasonic atomization were experimentally studied. The samples were aqueous solutions of methanol, ethanol and 1-propanol. The diameter distribution of atomized droplets showed the normal distribution, and the median diameter and standard deviation were expressed by means of the ultrasonic condition and the liquid properties. The concentration characteristic in ultrasonic atomization was analyzed by using the model of shell and core to the atomized droplet, where the former and latter consist of solute and solution, respectively. The value, which was surface solute amount in droplet multiplied by the molecular volume, increased with increasing solute molar fraction in bulk liquid and was independent of alcohol kinds. The rate of accompanying liquid and the solute molar fraction in accompanied liquid were estimated from the diameter distribution and the surface solute amount in droplet.

  10. Measurement of Diameter Changes during Irradiation Testing

    Energy Technology Data Exchange (ETDEWEB)

    Davis, K. L. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Knudson, D. L. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Crepeau, J. C. [Univ. of Idaho, Idaho Falls, ID (United States); Solstad, S. [Inst. for Energy Technologoy, Halden (Norway)

    2015-03-01

    New materials are being considered for fuel, cladding, and structures in advanced and existing nuclear reactors. Such materials can experience significant dimensional and physical changes during irradiation. Currently in the US, such changes are measured by repeatedly irradiating a specimen for a specified period of time and then removing it from the reactor for evaluation. The time and labor to remove, examine, and return irradiated samples for each measurement makes this approach very expensive. In addition, such techniques provide limited data and handling may disturb the phenomena of interest. In-pile detection of changes in geometry is sorely needed to understand real-time behavior during irradiation testing of fuels and materials in high flux US Material and Test Reactors (MTRs). This paper presents development results of an advanced Linear Variable Differential Transformer-based test rig capable of detecting real-time changes in diameter of fuel rods or material samples during irradiation in US MTRs. This test rig is being developed at the Idaho National Laboratory and will provide experimenters with a unique capability to measure diameter changes associated with fuel and cladding swelling, pellet-clad interaction, and crud buildup.

  11. Sagittal Abdominal Diameter: Application in Clinical Practice

    Directory of Open Access Journals (Sweden)

    Thaís Da Silva-Ferreira

    2014-05-01

    Full Text Available Excess visceral fat is associated with cardiovascular risk factors. Sagittal abdominal diameter (SAD has recently been highlighted as an indicator of abdominal obesity, and also may be useful in predicting cardiovascular risk. The purpose of the present study was to review the scientific literature on the use of SAD in adult nutritional assessment. A search was conducted for scientific articles in the following electronic databases: SciELO , MEDLINE (PubMed and Virtual Health Library. SAD is more associated with abdominal fat (especially visceral, and with different cardiovascular risk factors, such as, insulin resistance, blood pressure, and serum lipoproteins than the traditional methods of estimating adiposity, such as body mass index and waist-to-hip ratio. SAD can also be used in association with other anthropometric measures. There are still no cut-off limits established to classify SAD as yet. SAD can be an alternative measure to estimate visceral adiposity. However, the few studies on this diameter, and the lack of consensus on the anatomical site to measure SAD, are obstacles to establish cut-off limits to classify it.

  12. Multi-scale analysis of the effect of nano-filler particle diameter on the physical properties of CAD/CAM composite resin blocks.

    Science.gov (United States)

    Yamaguchi, Satoshi; Inoue, Sayuri; Sakai, Takahiko; Abe, Tomohiro; Kitagawa, Haruaki; Imazato, Satoshi

    2017-05-01

    The objective of this study was to assess the effect of silica nano-filler particle diameters in a computer-aided design/manufacturing (CAD/CAM) composite resin (CR) block on physical properties at the multi-scale in silico. CAD/CAM CR blocks were modeled, consisting of silica nano-filler particles (20, 40, 60, 80, and 100 nm) and matrix (Bis-GMA/TEGDMA), with filler volume contents of 55.161%. Calculation of Young's moduli and Poisson's ratios for the block at macro-scale were analyzed by homogenization. Macro-scale CAD/CAM CR blocks (3 × 3 × 3 mm) were modeled and compressive strengths were defined when the fracture loads exceeded 6075 N. MPS values of the nano-scale models were compared by localization analysis. As the filler size decreased, Young's moduli and compressive strength increased, while Poisson's ratios and MPS decreased. All parameters were significantly correlated with the diameters of the filler particles (Pearson's correlation test, r = -0.949, 0.943, -0.951, 0.976, p CAD/CAM CR blocks can be enhanced by loading silica nanofiller particles of smaller diameter. CAD/CAM CR blocks by using smaller silica nano-filler particles have a potential to increase fracture resistance.

  13. Effect of Chloride Channels on Apoptotic Volume Decrease and Apoptosis in Nasopharyngeal Carcinoma Cells%氯通道在鼻咽癌细胞凋亡性细胞容积减小和细胞凋亡中的作用

    Institute of Scientific and Technical Information of China (English)

    潘廷才; 杨林杰; 刘善文; 李华荣; 朱林燕; 叶文才; 王立伟; 陈丽新

    2011-01-01

    目的:探讨氯通道在5-氟尿嘧啶(5-Fu)诱导的低分化鼻咽癌细胞CNE-2Z凋亡性细胞容积减小(AVD)和细胞凋亡中的作用.方法:培养CNE-2Z细胞后,分别用100μmol/L 5-Fu(5-Fu组)、100μmol/L 5-Fu+100μmol/L 5-硝基-2-(3-苯丙胺)苯甲酸(5-Fu+NPPB组)处理细胞,采用活细胞影像系统实时拍摄细胞图像,检测细胞容积变化,Hochest 33258荧光染色技术检测细胞凋亡并计算细胞凋亡率.结果:5-Fu处理使细胞皱缩,体积变小;5-Fu+NPPB处理后细胞体积变化不明显.在5个不同时间点,细胞受到5-Fu刺激后,标准化细胞容积(Vst)均小于对照组,5-Fu+NPPB组对细胞Vst的影响均小于5-Fu组,差异均有统计学意义.对照组细胞凋亡率(1.8+0.5)%,5-Fu处理使细胞凋亡率增加至(49.2±2.6)%,5-Fu+NPPB处理使细胞凋亡率降至(12.5±2.9)%.结论:抑制氯通道可显著拮抗5-Fu诱导的凋亡性细胞容积减小和细胞凋亡.%Objective: To investigate the roles of chloride channels in apoptotic volume decrease (AVD) and apoptosis in nasopharyngeal carcinoma cells (CNE-2Z). Methods: The CNE-2Z was cultured and treated with 100 μmol/L 5-Fu (5-Fu group), 100 μmol/L 5-Fu+l00 μmol/L 5-nitro-2-(3-phenylpropylamino) henzoic acid (5-Fu+NPPB group). Changes of the cell volume were monitored and analyzed by the time-lapse imaging technique. Cell apoptotic rates were measured and analysed by Hoechst 33258 staining. Results : The results showed that 5-Fu induced the early cell volume decrease in a few minutes. The cell shrinkage and volume decrease were found after 5-Fu treatment. No significant change was found in cell volume after treatment with 5-Fu+NPPB. The cell volumes were significantly decreased in 5 time points in 5-Fu group than those of control. The effect of 5-Fu+NPPB on the cell volume was significantly smaller than that of 5-Fu. The apoptotic rate induced by 5-Fu was (49.2±2.6)% compared with (1.8±0.5)% in control group. The apoptotic rate was

  14. Influence of Age and Apical Diameter on the Success of Endodontic Regeneration Procedures.

    Science.gov (United States)

    Estefan, Bishoy Safwat; El Batouty, Kariem Mostafa; Nagy, Mohamed Mokhtar; Diogenes, Anibal

    2016-11-01

    Treatment of immature permanent teeth with necrotic pulp and apical pathosis constitutes a challenge for endodontists. The present study was done to evaluate the effect of age and apical diameter on the regenerative potential of young permanent immature teeth with necrotic pulps. Immature necrotic permanent maxillary incisors (n = 40) of patients 9-18 years old were divided into 2 groups according to the treatment protocol: group Y (younger age group), 9-13 years and group O (older age group), 14-18 years. Each group was further subdivided into 2 subgroups according to apical diameter, subgroup (n) (narrower diameter) between 0.5 and 1 mm and subgroup (w) (wider diameter) equal to or greater than 1 mm. Revascularization procedures were performed for all patients. Follow-up was done for up to 12 months. Standardized radiographs were digitally evaluated for increase in root length and thickness and decrease in apical diameter. After the follow-up period, most of the cases demonstrated radiographic evidence of periapical healing. Group Y showed significant progressive increase in root length and width and decrease in apical diameter. Subgroup (w) representing wider apical diameter showed significant progress as well. It was found that revascularization procedures can be implemented in any age ranging from 9 to 18 years; however, younger age groups were better candidates for revascularization procedure than older ones. Regarding the apical diameter, regeneration procedures were successful with apical diameters as small as 0.5 mm. However, teeth with preoperative wider diameters (≥1 mm) demonstrated greater increase in root thickness, length, and apical narrowing. Copyright © 2016 American Association of Endodontists. All rights reserved.

  15. Diameter and Temperature Dependence of Thermal Conductivity of Single-Walled Carbon Nanotubes

    Institute of Scientific and Technical Information of China (English)

    PAN Rui-Qin

    2011-01-01

    Temperature and diameter dependence of the thermal conductivity of several armchair single-walled carbon nan-otubes (SWNTs) are studied by nonequilibrium molecular dynamics method with Brenner II potential. The thermal conductivities are calculated at temperatures from WOK to 600K. It is found that the thermal conductivity decreases as the temperature increases and increases as the diameter of SWNT increases. The results demonstrate that these two phenomena are due to the onset of the Umklapp process.%@@ Temperature and diameter dependence of the thermal conductivity of several armchair single-walled carbon nan- otubes (SWNTs) are studied by nonequilibrium molecular dynamics method with Brenner Ⅱ potential.The thermal conductivities are calculated at temperatures from 100K to 600K.It is found that the thermal con- ductivity decreases as the temperature increases and increases as the diameter of SWNT increases.The results demonstrate that these two phenomena are due to the onset of the Umklapp process.

  16. Two-phase flow patterns for flow condensation in small-diameter tubes

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Two-phase flow patterns have been observed visually to investigate the effects of tube diameter, mass flux and tube inclination on flow condensation in small-diameter tubes. For horizontal or inclined small-diameter tubes, gravity-domination is decreased by shear stress and surface tension on phase change interface, which weakens the stratification of condensate and vapor flow due to the action of gravity perpendicular to flow direction. As decreasing the tube diameter from 5.79 mm to 2.18 mm, the annular or sub-annular flows become prevailing in flow regime map. The existing flow regime maps for macro scale cannot predict the experimental data in the present study.

  17. Fire protection covering for small diameter missiles

    Science.gov (United States)

    Riccitiello, S. R.; Sawko, P. M. (Inventor)

    1979-01-01

    Flexible intumescent protection sheeting of unusually uniform thickness were prepared from epoxy-polysulfide compositions, containing microfibers and the ammonium salt of 1,4-nitroaniline-2-sulfonic acid, as disclosed in U.S. Pat. No. 3,663,464, except that an ammonium salt particle size in the order of 5 to 8 microns and a fiber size of about 1/128th inch in length and 3 to 5 microns in diameter were found critical to obtain the required density of 1.46 to 1.50 g/cc. The insulation sheeting was prepared by a continuous process involving vacuum mixing, calendering, and curing under very strict conditions which depend to some extent upon the thickness of the sheet produced.

  18. Diameter-Controllable Magnetic Properties of Co Nanowire Arrays by Pulsed Electrodeposition

    Directory of Open Access Journals (Sweden)

    Youwen Yang

    2010-01-01

    Full Text Available The Co nanowires with different diameters were prepared by pulsed electrodeposition into anodic alumina membranes oxide templates. The micrographs and crystal structures of nanowires were studied by FE-SEM, TEM, and XRD. Due to their cylindrical shape, the nanowires exhibit perpendicular anisotropy. The coercivity and loop squareness (Mr/Ms of Co nanowires depend strongly on the diameter. Both coercivity and Mr/Ms decrease with increasing wire diameter. The behavior of the nanowires is explained briefly in terms of localized magnetization reversal.

  19. Diameter-dependent electronic transport properties of Au-catalyst/Ge-nanowire Schottky diodes

    Energy Technology Data Exchange (ETDEWEB)

    Picraux, S Thomas [Los Alamos National Laboratory; Leonard, Francois [SNL; Swartzentruber, Brian S [SNL; Talin, A Alee [SNL

    2008-01-01

    We present electronic transport measurements in individual Au-catalyst/Ge-nanowire interfaces demonstrating the presence of a Schottky barrier. Surprisingly, the small-bias conductance density increases with decreasing diameter. Theoretical calculations suggest that this effect arises because electron-hole recombination in the depletion region is the dominant charge transport mechanism, with a diameter dependence of both the depletion width and the electron-hole recombination time. The recombination time is dominated by surface contributions and depends linearly on the nanowire diameter.

  20. Study of the operational parameters of crops turbine sprayer (turbo liner on spray quality and diameter of droplets, using image processing

    Directory of Open Access Journals (Sweden)

    F Behzadi Pour

    2017-05-01

    median numerical diameter (NMD and spraying quality indicator were calculated. A Spectrophotometry device at the wavelength of 427 nm, Image J and sas 9.2 software were used for measurement. This research was carried out in accordance with the calendar crop canola spraying in field conditions and the weather was calm that the wind speed was 0- 2.5 km hr-1, relative humidity was 29.7% - 32.5% and air temperature was 18.8˚C – 20.7˚C. Results and Discussion According to the results sprayer pressure, fan speed and forward speed were shown significantly different (P≤0.01 on the volume diameter of 50% (DV50 and median numerical diameter (NMD. The effect of spraying pressure on distributing quality indicator was shown significant (P ≤ 0.01, but the fan and forward speed did not shown any significant effect. Mean comparison of the interaction of pressure and forward speed on the spray quality index and the number median diameter were shown significant (P ≤ 0.01, but they did not shown any significant effect on the volume diameter of 50% (DV50. With increasing spraying pressure and fan speed, the droplet size, volume diameter of 50% (DV50 at 72% and numerical median diameter (NMD at 69% and distributing quality indicator at 46% were decreased that were corresponded with the result of Czaczyk et al. (2012, Peyman et al. (2011, Nuyttens et al. (2009 and Landers and Farooq (2004. With increasing spraying pressure and forward speed, the droplet size, numerical median diameter (NMD at 63% and distributing quality indicator at 35% were decreased that these resulted were corresponded with the results of Naseri et al. (2007 and Dorr et al. (2013. Conclusions With increasing spraying pressure, fan and forward speed, the droplet size, volume diameter of 50% (DV50 and numerical median diameter (NMD were decreased. Therefore, spraying quality indicator was decreased. The maximum pressure (35 bars, maximum fan speed (2430 rpm and maximum forward speed (13.5 km hr-1 were able to

  1. LED-based digital diameter measurement

    Science.gov (United States)

    Kleuver, Wolfram; Becker, Lothar

    1995-01-01

    This paper presents a new industrial sensor for measuring diameters of extreme thin objects. The system is divided in two parts. The first is the emitter and the second the receiver. It is possible to use this system for the automatic inspection of files and wires in the textile industries and wire works. Another application for the sensor is the control of production of chemical files in an extruder. Furthermore we can measure more than one object in the lightbeam because we get information not only about the dimensions also about the position of the objects in the beam. The innovation in this system is the using of a light emitting diode (LED) as emitter and the realization of a long distance of about two or more meters between the two sensorheads. The results of this development are a special kind of optical layout in the emitter to reduce the loss of intensity and minimize the divergence of the lightbeam. It is not necessary to develop an intensity distribution, which is equal over the complete width of the sensorhead. We can show that we have a better dynamic in the system with this feature. The experiments prove that we get the same resolution as a laserbeamsensor. Furthermore one advantage is the eye-safety.

  2. Improving microalgal growth with reduced diameters of aeration bubbles and enhanced mass transfer of solution in an oscillating flow field.

    Science.gov (United States)

    Yang, Zongbo; Cheng, Jun; Lin, Richen; Zhou, Junhu; Cen, Kefa

    2016-07-01

    A novel oscillating gas aerator combined with an oscillating baffle was proposed to generate smaller aeration bubbles and enhance solution mass transfer, which can improve microalgal growth in a raceway pond. A high-speed photography system (HSP) was used to measure bubble diameter and generation time, and online precise dissolved oxygen probes and pH probes were used to measure mass-transfer coefficient and mixing time. Bubble diameter and generation time decreased with decreased aeration gas rate, decreased orifice diameter, and increased water velocity in the oscillating gas aerator. The optimized oscillating gas aerator decreased bubble diameter and generation time by 25% and 58%, respectively, compared with a horizontal tubular gas aerator. Using an oscillating gas aerator and an oscillating baffle in a raceway pond increased the solution mass-transfer coefficient by 15% and decreased mixing time by 32%; consequently, microalgal biomass yield increased by 19%.

  3. Mockup Small-Diameter Air Distribution System

    Energy Technology Data Exchange (ETDEWEB)

    A. Poerschke and A. Rudd

    2016-05-01

    This report investigates the feasibility of using a home-run manifold small-diameter duct system to provide space conditioning air to individual thermal zones in a low-load home. This compact layout allows duct systems to be brought easily within conditioned space via interior partition walls. Centrally locating the air hander unit in the house significantly reduces duct lengths. The plenum box is designed so that each connected duct receives an equal amount of airflow, regardless of the duct position on the box. Furthermore, within a reasonable set of length restrictions, each duct continues to receive similar airflow. The design method uses an additive approach to reach the total needed zonal airflow. Once the cubic feet per minute needed to satisfy the thermal load of a zone has been determined, the total number of duct runs to a zone can be calculated by dividing the required airflow by the standard airflow from each duct. The additive approach greatly simplifies the design effort and reduces the potential for duct design mistakes to be made. Measured results indicate that this plenum design can satisfy the heating load. However, the total airflow falls short of satisfying the cooling load in a hypothetical building. Static pressure inside the plenum box of 51.5 Pa limited the total airflow of the attached mini-split heat pump blower, thus limiting the total thermal capacity. Fan energy consumption is kept to 0.16 to 0.22 watt/CFM by using short duct runs and smooth duct material.

  4. Decreasing relative risk premium

    DEFF Research Database (Denmark)

    Hansen, Frank

    2007-01-01

    such that the corresponding relative risk premium is a decreasing function of present wealth, and we determine the set of associated utility functions. We find a new characterization of risk vulnerability and determine a large set of utility functions, closed under summation and composition, which are both risk vulnerable...... and have decreasing relative risk premium. We finally introduce the notion of partial risk neutral preferences on binary lotteries and show that partial risk neutrality is equivalent to preferences with decreasing relative risk premium...

  5. Delayed ICD lead cardiac perforation: comparison of small versus standard-diameter leads implanted in a single center.

    Science.gov (United States)

    Rordorf, Roberto; Canevese, Fabio; Vicentini, Alessandro; Petracci, Barbara; Savastano, Simone; Sanzo, Antonio; Gandolfi, Edoardo; Dore, Roberto; Landolina, Maurizio

    2011-04-01

    An increased risk of delayed cardiac perforation (DCP) with active-fixation small-diameter ICD leads has recently been reported, especially with regard to the St. Jude Riata lead (St. Jude Medical, Sylmar, CA, USA). Few data on the risk of DCP in small versus standard-diameter leads implanted in a single high-volume center are available. Moreover, no data on the performances of St. Jude's new small-diameter Durata lead are as yet available. The aim of this study was to assess the incidence of DCP in small versus standard-diameter leads implanted in our center. Between January 2003 and October 2009, 437 small-diameter leads (190 Medtronic Sprint Fidelis [Medtronic Inc., Minneapolis, MN, USA], 196 Riata, 51 Durata) and 421 standard-diameter (>8 Fr) leads were implanted. After a median follow-up of 421 days seven of 858 (0.8%) patients experienced DCP. The incidence of DCP was higher in patients with small-diameter leads than in those with standard-diameter leads (1.6% vs 0%, P = 0.01). No cases of DCP occurred among 371 passive-fixation leads versus 1.4% of events among active-fixation leads (P = 0.02). The incidence of DCP was 2.5% in Riata, 1% in Sprint Fidelis, 0% in Durata, and 0% in standard-diameter leads (P < 0.01 for Riata vs standard-diameter leads). Small-diameter active-fixation ICD leads are at increased risk of DCP, a finding mostly due to the higher incidence of events in the Riata family. By contrast, passive-fixation small-diameter leads and standard-diameter leads appear to be safe enough regarding the risk of DCP. Our preliminary data suggest that the new Durata lead is not associated with an increased risk of DCP. ©2010, The Authors. Journal compilation ©2010 Wiley Periodicals, Inc.

  6. Effect of sample diameter on primary dendrite spacing of directionally solidified Al-4%Cu alloy

    Institute of Scientific and Technical Information of China (English)

    QU Min; LIU Lin; TANG Feng-tao; ZHANG Jun; FU Heng-zhi

    2009-01-01

    The relationship between primary dendrite arm spacing and sample diameter was studied during directional solidification for Al-4%Cu (mass fraction) alloy. It is shown that primary dendrite spacing is decreased with the decrease of the sample diameter at given growth rate. By regressing the relationship between primary dendrite arm spacing and the growth rate, the primary dendrite arm spacing complies with 461.76v-0.53, 417.92v-0.28 and 415.83v-0.25 for the sample diameter of 1.8, 3.5 and 7.2 mm, respectively. The primary dendrite spacing, growth rate and thermal gradient for different sample diameters comply with 28.77v-0.35G-0.70, 23.17v-0.35G-0.70 and 23.84v-0.35G-0.70, respectively. They are all consistent with the theoretical model , and b1/a1=2. By analyzing the experimental results with classical models, it is shown that KURZ-FISHER model fits for the primary dendrite spacing in smaller sample diameters with weaker thermosolute convection. Whereas TRIVEDI model is suitable for describing primary dendrite arm spacing with a larger diameter (d>2 mm) where convection should be considered.

  7. Control of diameter and morphology of poly(vinylidene fluoride) nanofibers fabricated by electrospinning

    Science.gov (United States)

    Jing, Hongjun; Du, Xiaosong; Jiang, Yadong

    2009-11-01

    This paper described a procedure based on electrospinning for generating nanofibers with controllable diameters and morphology. When an acetone and N,N-dimethylacetamide (DMAc) mixture solvent containing poly(vinylidene fluoride) (PVDF) was injected through a needle under a strong electric field, nanofibers made of PVDF formed as a result of electrostatic jetting. To control the diameter and morphology of PVDF nanofibers, the solution properties and process parameters were investigated, such as polymer concentration, the ratio of the mixture solvent, feeding rate, applied electric field, and needle-to-collector distance. The fabricated fibers were 30-8000 nm in diameter. The increase in the polymer concentration caused an increase in the fiber diameter. However, the increase in the feeding rate and applied electric field decreased the fiber diameter. Variation in the needle-to-collector distance did not result in significant changes in the fiber diameter. The ratio of the solvent also had a very significant impact on electrospinning. The diameter and morphology of the PVDF nanofibers were characterized by optical microscope and scanning electron microscope (SEM).

  8. Effects of the hydraulic coupling between xylem and phloem on diurnal phloem diameter variation.

    Science.gov (United States)

    Sevanto, Sanna; Hölttä, Teemu; Holbrook, N Michele

    2011-04-01

    Measurements of diurnal diameter variations of the xylem and phloem are a promising tool for studying plant hydraulics and xylem-phloem interactions in field conditions. However, both the theoretical framework and the experimental verification needed to interpret phloem diameter data are incomplete. In this study, we analytically evaluate the effects of changing the radial conductance between the xylem and the phloem on phloem diameter variations and test the theory using simple manipulation experiments. Our results show that phloem diameter variations are mainly caused by changes in the radial flow rate of water between the xylem and the phloem. Reducing the hydraulic conductance between these tissues decreases the amplitude of phloem diameter variation and increases the time lag between xylem and phloem diameter variation in a predictable manner. Variation in the amplitude and timing of diameter variations that cannot be explained by changes in the hydraulic conductance, could be related to changes in the osmotic concentration in the phloem. © 2011 Blackwell Publishing Ltd.

  9. Volume Entropy

    CERN Document Server

    Astuti, Valerio; Rovelli, Carlo

    2016-01-01

    Building on a technical result by Brunnemann and Rideout on the spectrum of the Volume operator in Loop Quantum Gravity, we show that the dimension of the space of the quadrivalent states --with finite-volume individual nodes-- describing a region with total volume smaller than $V$, has \\emph{finite} dimension, bounded by $V \\log V$. This allows us to introduce the notion of "volume entropy": the von Neumann entropy associated to the measurement of volume.

  10. Small-Diameter PTFE Portosystemic Shunts: Portocaval vs Mesocaval

    Directory of Open Access Journals (Sweden)

    Robert Shields

    1998-01-01

    Full Text Available Fifty-seven patients with failed sclerotherapy received a mesocaval interposition shunt with an externally supported, ringed polytetrafluoroethylene prosthesis of either 10 or 12 mm diameter. Thirty-one patients had Child-Pugh gradeA disease and 26 grade B; all had a liver volume of 1000– 2500 ml. Follow-up ranged from 16 months to 6 years 3 months. Three patients (5 per cent died in the postoperative period. There were two postoperative recurrences of variceal haemorrhage and one recurrent bleed in the second year after surgery. The cumulative shunt patency rate was 95 per cent and the incidence of encephalopathy 9 per cent; the latter was successfully managed by protein restriction and/or lactulose therapy. The actuarial survival rate for the whole group at 6 years was 78 per cent, for those with Child-Pugh grade A 88 per cent and for grade B 67 per cent. Small-lumen mesocaval interposition shunting achieves portal decompression, preserves hepatopetal flow, has a low incidence of shunt thrombosis, prevents recurrent variceal bleeding and is not associated with significant postoperative encephalopathy.

  11. Multi-diameter silicon nanowires: Fabrication, characterization, and modeling

    Science.gov (United States)

    Alagoz, Arif Sinan

    Nanotechnology is a rapidly expanding interdisciplinary field offering novel devices for broad range of applications. Quantum effects and surface to volume ratio of nanostructures are strongly size dependent, and redefine material properties at nanoscale. Silicon is one of the most promising materials for next generation nanostructured transistors, photonics devices, Li-ion batteries, photovoltaic solar cells, and thermoelectric energy generators. Since electrical, optical, and mechanical properties of nanostructures strongly depend on their shape, size, periodicity, and crystal structure; it is crucial to control these parameters in order to optimize device performance for targeted applications. This dissertation is intended to develop a low-cost, low-temperature, high-throughput, and large-area nanowire fabrication method that can produce well-ordered arrays of hierarchical single-crystal silicon nanowires at large scale by using nanosphere lithography and metal-assisted chemical etching. Nanowire morphology was characterized by using scanning electron microscope and optical properties of nanowire arrays were modeled with the help of finite-difference-time domain method. These novel multi-diameter silicon nanowire arrays have the potential applications in many fields including but not limited to next generation nanowire solar cells to field ionization gas sensors.

  12. Numerical Simulation of Large Diameter Cylindrical Structure Slamming

    Institute of Scientific and Technical Information of China (English)

    XU Jing; WANG De-yu

    2008-01-01

    The water entry of large diameter cylindrical structure is studied by applying numerical simulation method. The processes of different diameter cylindrical structures impacting water with various constant velocities are calculated numerically. Thereafter, analyzed are the distribution of slamming pressure on structure during slamming course and the influence of slamming velocity and cylindrical diameter on slamming process. Furthermore, presented herein is an equation being used to forecast the peak slamming force on a large diameter cylindrical structure.

  13. Decreased Vertebral Artery Hemodynamics in Patients with Loss of Cervical Lordosis.

    Science.gov (United States)

    Bulut, Mehmet Deniz; Alpayci, Mahmut; Şenköy, Emre; Bora, Aydin; Yazmalar, Levent; Yavuz, Alpaslan; Gülşen, İsmail

    2016-02-15

    BACKGROUND Because loss of cervical lordosis leads to disrupted biomechanics, the natural lordotic curvature is considered to be an ideal posture for the cervical spine. The vertebral arteries proceed in the transverse foramen of each cervical vertebra. Considering that the vertebral arteries travel in close anatomical relationship to the cervical spine, we speculated that the loss of cervical lordosis may affect vertebral artery hemodynamics. The aim of this study was to compare the vertebral artery values between subjects with and without loss of cervical lordosis. MATERIAL AND METHODS Thirty patients with loss of cervical lordosis and 30 controls matched for age, sex, and body mass index were included in the study. Sixty vertebral arteries in patients with loss of cervical lordosis and 60 in controls without loss of cervical lordosis were evaluated by Doppler ultrasonography. Vertebral artery hemodynamics, including lumen diameter, flow volume, peak systolic velocity, end-diastolic velocity, and resistive index, were measured, and determined values were statistically compared between the patient and the control groups. RESULTS The means of diameter (p=0.003), flow volume (p=0.002), and peak systolic velocity (p=0.014) in patients were significantly lower as compared to controls. However, there was no significant difference between the 2 groups in terms of the end-diastolic velocity (p=0.276) and resistive index (p=0.536) parameters. CONCLUSIONS The present study revealed a significant association between loss of cervical lordosis and decreased vertebral artery hemodynamics, including diameter, flow volume, and peak systolic velocity. Further studies are required to confirm these findings and to investigate their possible clinical implications.

  14. The diameter-dependent photoelectrochemical performance of silicon nanowires.

    Science.gov (United States)

    Zhang, Bing-Chang; Wang, Hui; He, Le; Duan, Chun-Yang; Li, Fan; Ou, Xue-Mei; Sun, Bao-Quan; Zhang, Xiao-Hong

    2016-01-25

    We demonstrate the first systematic study of the diameter-dependent photoelectrochemical performance of single silicon nanowires within a broad size range from 200 to 2000 nm. SiNWs with a diameter of 1415 nm exhibit the highest solar energy conversion efficiency, which can be mainly traced to their diameter-dependent light absorption properties.

  15. Community biomass handbook volume 4: enterprise development for integrated wood manufacturing

    Science.gov (United States)

    Eini Lowell; D.R. Becker; D. Smith; M. Kauffman; D. Bihn

    2017-01-01

    The Community Biomass Handbook Volume 4: Enterprise Development for Integrated Wood Manufacturing is a guide for creating sustainable business enterprises using small diameter logs and biomass. This fourth volume is a companion to three Community Biomass Handbook volumes: Volume 1: Thermal Wood Energy; Volume 2: Alaska, Where Woody Biomass Can Work; and Volume 3: How...

  16. The influence of upper airways diameter on the intensity of obstructive sleep apnea

    Directory of Open Access Journals (Sweden)

    Jolanta Szymańska

    2014-03-01

    Full Text Available Introduction and Objective. Obstructive sleep apnea (OSA is characterized by at least 5 ten-second-long episodes of apnea or hypopnea, per hour of sleep. This disease may lead to severe, life-threatening complications. Therefore, risk analysis and its influence on disease intensity is crucial for proper implementation of preventive treatments. Objective. To determine the relation between the intensity of OSA expressed in Apnea-Hypopnea Index (AHI, and the anterior-posterior diameter of upper airways at the levels of soft palate and tongue base. Material and Method. Medical records of 41 patients with sleep apnea (AHI>4 diagnosed through polysomnographic examination obstructive were used for the study. The data consisted of: age and gender, polysomnographic examination results (AHI, lateral cephalogram with cephalomertic analysis, together with measurements of the upper and lower pharyngeal depth according to McNamara. Statistical analysis was carried out in accordance with Pearson’s r correlation coefficient test (Statistica 8.0 software package. Results. Analysis of the influence of upper airways diameter on the intensity of OSA showed that the value of upper Airways diameter at the tongue base level had no statistically significant impact on the value of AHI (p=0.795. However, a statistically significant impact of the value of upper airways diameter on the AHI value (p=0.008 at the soft palate level was observed. Patients with OSA have narrowed upper airways diameter. The value of AHI increases with the decrease of upper diameter and is not dependent on a lower diameter value. Patients with a decreased upper airways diameter should be informed about potential breathing disorders during sleep.

  17. Effect of Tree Spacing on Tree Level Volume Growth, Morphology, and Wood Properties in a 25-Year-Old Pinus banksiana Plantation in the Boreal Forest of Quebec

    Directory of Open Access Journals (Sweden)

    François Hébert

    2016-11-01

    Full Text Available The number of planted trees per hectare influences individual volume growth, which in turn can affect wood properties. The objective of this study was to assess the effect of six different plantation spacings of jack pine (Pinus banksiana Lamb. 25 years following planting on tree growth, morphology, and wood properties. Stem analyses were performed to calculate annual and cumulative diameter, height, and volume growth. For morphological and wood property measurements several parameters were analyzed: diameter of the largest branch, live crown ratio, wood density, and the moduli of elasticity and rupture on small clear samples. The highest volume growth for individual trees was obtained in the 1111 trees/ha plantation, while the lowest was in the 4444 trees/ha plantation. Wood density and the moduli of elasticity and rupture did not change significantly between the six plantation spacings, but the largest branch diameter was significantly higher in the 1111 trees/ha (3.26 cm mean diameter compared with the 4444 trees/ha spacing (2.03 cm mean diameter. Based on this study, a wide range of spacing induced little negative effect on the measured wood properties, except for the size of knots. Increasing the initial spacing of jack pine plantations appears to be a good choice if producing large, fast-growing stems is the primary goal, but lumber mechanical and visual properties could be decreased due to the larger branch diameter.

  18. The k-Diameter of a Kind of Circulant Graph

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xian-di

    2004-01-01

    The diameter of a graph G is the maximal distance between pairs of vertices of G. When a network is modeled as a graph,diameter is a measurement for maximum transmission delay. The k-diameter dk(G) of a graph G, which deals with k internally disjoint paths between pairs of vertices of G, is a extension of the diameter of G. It has widely studied in graph theory and computer science. The circulant graph is a group-theoretic model of a class of symmetric interconnection network. Let Cn(i, ) be a circulant graph of order n whose spanning elements are i and , where n≥4 and n is even. In this paper, the diameter, 2-diameter and 3-diameter of the Cn(i,) are all obtained if gcd(n,i)=1, where the symbol gcd(n,i) denotes the maximum common divisor of n and i.

  19. Tool Geometry for Friction Stir Welding—Optimum Shoulder Diameter

    Science.gov (United States)

    Mehta, M.; Arora, A.; de, A.; Debroy, T.

    2011-09-01

    The most important geometric parameter in the friction stir welding (FSW) tool design is the shoulder diameter, which is currently estimated by trial and error. Here, we report a combined experimental and theoretical investigation on the influence of shoulder diameter on thermal cycles, peak temperatures, power requirements, and torque during FSW of AA7075-T6. An optimum tool shoulder diameter is identified using a three-dimensional, heat transfer and materials flow model. First, the predictive capability of the model is tested by comparing the computed values of peak temperature, spindle power, and torque requirements for various shoulder diameters against the corresponding experimental data. The change in the values of these variables with shoulder diameter is correctly predicted by the model. The model is then used to identify the optimum tool shoulder diameter that facilitates maximal use of the supplied torque in overcoming interfacial sticking. The tool with optimum shoulder diameter is shown to result in acceptable yield strength (YS) and ductility.

  20. Decreasing Relative Risk Premium

    DEFF Research Database (Denmark)

    Hansen, Frank

    We consider the risk premium demanded by a decision maker with wealth x in order to be indifferent between obtaining a new level of wealth y1 with certainty, or to participate in a lottery which either results in unchanged present wealth or a level of wealth y2 > y1. We define the relative risk...... premium as the quotient between the risk premium and the increase in wealth y1–x which the decision maker puts on the line by choosing the lottery in place of receiving y1 with certainty. We study preferences such that the relative risk premium is a decreasing function of present wealth, and we determine...... relative risk premium in the small implies decreasing relative risk premium in the large, and decreasing relative risk premium everywhere implies risk aversion. We finally show that preferences with decreasing relative risk premium may be equivalently expressed in terms of certain preferences on risky...

  1. Decreasing Serial Cost Sharing

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Østerdal, Lars Peter

    The increasing serial cost sharing rule of Moulin and Shenker [Econometrica 60 (1992) 1009] and the decreasing serial rule of de Frutos [Journal of Economic Theory 79 (1998) 245] have attracted attention due to their intuitive appeal and striking incentive properties. An axiomatic characterization...... of the increasing serial rule was provided by Moulin and Shenker [Journal of Economic Theory 64 (1994) 178]. This paper gives an axiomatic characterization of the decreasing serial rule...

  2. Serial Measurements of Splanchnic Vein Diameters in RatsUsing High-Frequency Ultrasound

    Directory of Open Access Journals (Sweden)

    Bridget M Seitz

    2016-05-01

    Full Text Available The purpose of this study was to investigate serial ultrasound imaging in rats as a fully non-invasive method to 1 quantify the diameters of splanchnic veins in real time as an indirect surrogate for the capacitance function of those veins, and 2 assess the effects of drugs on venous dimensions. A 21 MHz probe was used on anesthetized male Sprague-Dawley rats to collect images containing the portal vein (PV, superior mesenteric vein (SMV, abdominal inferior vena cava (IVC, and splenic vein (SpV; used as a landmark in timed studies and the abdominal aorta (AA. Stable landmarks were established that allowed reproducible quantification of cross-sectional diameters within an animal. The average diameters of vessels measured every 5 minutes over 45 minutes remained within 0.75±0.15% (PV, 0.2±0.09% (SMV, 0.5±0.12% (IVC and 0.38±0.06% (AA of baseline (PV: 2.0±0.12 mm; SMV: 1.7±0.04 mm; IVC: 3.2±0.1 mm; AA: 2.3±0.14 mm. The maximal effects of the vasodilator sodium nitroprusside (SNP; 2 mg/kg, i.v. bolus on venous diameters were determined 5 minutes post SNP bolus; the diameters of all noted veins were significantly increased by sodium nitroprusside, while mean arterial pressure decreased 29±4 mmHg. By contrast, administration of the venoconstrictor sarafotoxin (S6c; 5 ng/kg, i.v. bolus significantly decreased PV and SpV, but not IVC, SMV or AA, diameters 5 minutes post S6c bolus; mean arterial pressure increased by 6±2 mmHg. In order to determine if resting splanchnic vein diameters were stable over much longer periods of time, vessel diameters were measured every two weeks for 8 weeks. Measurements were found to be highly reproducible within animals over this time period. Finally, to evaluate the utility of vein imaging in a chronic condition, images were acquired from 4-week deoxycorticosterone acetate salt (DOCA-salt hypertensive and normotensive (SHAM control rats. All vessel diameters increased from baseline while mean arterial pressure

  3. Estimation of genetic parameters for wool fiber diameter measures.

    Science.gov (United States)

    Iman, N Y; Johnson, C L; Russell, W C; Stobart, R H

    1992-04-01

    Genetic and phenotypic correlations and heritability estimates of side, britch, and core diameters; side and britch CV; side and britch diameter difference; and clean fleece weight were investigated using 385 western white-faced ewes produced by 50 sires and maintained at two locations on a selection study. Data were analyzed using analysis of variance procedures, and effects in the final model included breed of sire-selection line combination, sire within breed-selection line, and location. Heritabilities were estimated by paternal half-sib analysis. Sires within breed-selection line represented a significant source of variation for all traits studied. Location had a significant effect on side diameter, side and britch diameter difference, and clean fleece weight. Age of ewe only affected clean fleece weight. Phenotypic and genetic correlations among side, britch, and core diameter measures were high and positive. Phenotypic correlations ranged from .68 to .75 and genetic correlations ranged from .74 to .89. The genetic correlations between side and britch diameter difference and side diameter or core diameter were small (-.16 and .28, respectively). However, there was a stronger genetic correlation between side and britch diameter difference and britch diameter (.55). Heritability of the difference between side and britch diameter was high (.46 +/- .16) and similar to heritability estimates reported for other wool traits. Results of this study indicate that relatively rapid genetic progress through selection for fiber diameter should be possible. In addition, increased uniformity in fiber diameter should be possible through selection for either side and britch diameter difference or side or britch CV.

  4. Analysis of Gear Wheel-shaft Joint Characterized by Comparable Pitch Diameter and Mounting Diameter

    Directory of Open Access Journals (Sweden)

    J. Ryś

    2003-01-01

    Full Text Available This paper presents the design procedure for a gear wheel-shaft direct frictional joint. The small difference between the operating pitch diameter of the gear and the mounting diameter of the frictional joint is the key feature of the connection. The contact surface of the frictional joint must be placed outside the bottom land of the gear, and the geometry of the joint is limited to the specific type of solutions.The strength analysis is based on the relation between the torque and statistical load intensity of the gear transmission. Several dimensionless parameters are introduced to simplify the calculations. Stress-strain verifying analysis with respect to combined loading, the condition of appropriate load-carrying capacity of the frictional joint and the fatigue strength of the shaft are applied to obtain the relations between the dimensions of the joint and other parameters. The final engineering solution may then be suggested. The approach is illustrated by a numerical example.The proposed procedure can be useful in design projects for small, high-powered modern reducers and new-generation geared motors, in particular when manufactured in various series of types.

  5. Decreasing strabismus surgery

    Science.gov (United States)

    Arora, A; Williams, B; Arora, A K; McNamara, R; Yates, J; Fielder, A

    2005-01-01

    Aim: To determine whether there has been a consistent change across countries and healthcare systems in the frequency of strabismus surgery in children over the past decade. Methods: Retrospective analysis of data on all strabismus surgery performed in NHS hospitals in England and Wales, on children aged 0–16 years between 1989 and 2000, and between 1994 and 2000 in Ontario (Canada) hospitals. These were compared with published data for Scotland, 1989–2000. Results: Between 1989 and 1999–2000 the number of strabismus procedures performed on children, 0–16 years, in England decreased by 41.2% from 15 083 to 8869. Combined medial rectus recession with lateral rectus resection decreased from 5538 to 3013 (45.6%) in the same period. Bimedial recessions increased from 489 to 762, oblique tenotomies from 43 to 121, and the use of adjustable sutures from 29 to 44, in 2000. In Ontario, operations for squint decreased from 2280 to 1685 (26.1%) among 0–16 year olds between 1994 and 2000. Conclusion: The clinical impression of decrease in the frequency of paediatric strabismus surgery is confirmed. In the authors’ opinion this cannot be fully explained by a decrease in births or by the method of healthcare funding. Two factors that might have contributed are better conservative strabismus management and increased subspecialisation that has improved the quality of surgery and the need for re-operation. This finding has a significant impact upon surgical services and also on the training of ophthalmologists. PMID:15774914

  6. Reliability of Two Diameters Method in Determining Acute Infarct Size. Validation as New Imaging Biomarker.

    Directory of Open Access Journals (Sweden)

    Jochen B Fiebach

    Full Text Available In order to select patients most likely to benefit for thrombolysis and to predict patient outcome in acute ischemic stroke, the volumetric assessment of the infarcted tissue is used. However, infarct volume estimation on Diffusion weighted imaging (DWI has moderate interrater variability despite the excellent contrast between ischemic lesion and healthy tissue. In this study, we compared volumetric measurements of DWI hyperintensity to a simple maximum orthogonal diameter approach to identify thresholds indicating infarct size >70 ml and >100 ml.Patients presenting with ischemic stroke with an NIHSS of ≥ 8 were examined with stroke MRI within 24 h after symptom onset. For assessment of the orthogonal DWI lesion diameters (od-values the image with the largest lesion appearance was chosen. The maximal diameter of the lesion was determined and a second diameter was measured perpendicular. Both diameters were multiplied. Od-values were compared to volumetric measurement and od-value thresholds identifying a lesion size of > 70 ml and > 100 ml were determined. In a selected dataset with an even distribution of lesion sizes we compared the results of the od value thresholds with results of the ABC/2 and estimations of lesion volumes made by two resident physicians.For 108 included patients (53 female, mean age 71.36 years with a median infarct volume of 13.4 ml we found an excellent correlation between volumetric measures and od-values (r2 = 0.951. Infarct volume >100 ml corresponds to an od-value cut off of 42; > 70 ml corresponds to an od-value of 32. In the compiled dataset (n = 50 od-value thresholds identified infarcts > 100 ml / > 70 ml with a sensitivity of 90%/ 93% and with a specificity of 98%/ 89%. The od-value offered a higher accuracy in identifying large infarctions compared to both visual estimations and the ABC/2 method.The simple od-value enables identification of large DWI lesions in acute stroke. The cutoff of 42 is useful to

  7. Decreasing relative risk premium

    DEFF Research Database (Denmark)

    Hansen, Frank

    2007-01-01

    We consider the risk premium demanded by a decision maker in order to be indifferent between obtaining a new level of wealth with certainty, or to participate in a lottery which either results in unchanged wealth or an even higher level than what can be obtained with certainty. We study preferences...... such that the corresponding relative risk premium is a decreasing function of present wealth, and we determine the set of associated utility functions. We find a new characterization of risk vulnerability and determine a large set of utility functions, closed under summation and composition, which are both risk vulnerable...... and have decreasing relative risk premium. We finally introduce the notion of partial risk neutral preferences on binary lotteries and show that partial risk neutrality is equivalent to preferences with decreasing relative risk premium...

  8. Plasma volume changes during hypoglycaemia

    DEFF Research Database (Denmark)

    Hilsted, J; Frandsen, Henrik Lund; Christensen, N J

    1991-01-01

    -induced hypoglycaemia with total autonomic blockade (alpha-adrenoceptor blockade combined with beta-adrenoceptor blockade and atropine); and insulin-induced hypoglycaemia without any autonomic blockade. In the experiments without autonomic blockade the peripheral venous hematocrit increased, plasma volume decreased......, intravascular albumin content decreased and the transcapillary escape rate of albumin increased. In both experiments with autonomic blockade the increase in venous haematocrit was abolished, yet plasma volume decreased, intravascular albumin content decreased and the transcapillary escape rate of albumin...... increased in these experiments. Thus, the changes in plasma volume and composition in response to hypoglycaemia are due to the combined actions of adrenaline and of insulin....

  9. Decreasing serial cost sharing

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Østerdal, Lars Peter Raahave

    2009-01-01

    The increasing serial cost sharing rule of Moulin and Shenker (Econometrica 60:1009-1037, 1992) and the decreasing serial rule of de Frutos (J Econ Theory 79:245-275, 1998) are known by their intuitive appeal and striking incentive properties. An axiomatic characterization of the increasing serial...

  10. Decreasing Serial Cost Sharing

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Østerdal, Lars Peter

    The increasing serial cost sharing rule of Moulin and Shenker [Econometrica 60 (1992) 1009] and the decreasing serial rule of de Frutos [Journal of Economic Theory 79 (1998) 245] have attracted attention due to their intuitive appeal and striking incentive properties. An axiomatic characterization...

  11. Gas slug ascent through changes in conduit diameter: Laboratory insights into a volcano-seismic source process in low-viscosity magmas

    Science.gov (United States)

    James, M.R.; Lane, S.J.; Chouet, B.A.

    2006-01-01

    Seismic signals generated during the flow and degassing of low-viscosity magmas include long-period (LP) and very-long-period (VLP) events, whose sources are often attributed to dynamic fluid processes within the conduit. We present the results of laboratory experiments designed to investigate whether the passage of a gas slug through regions of changing conduit diameter could act as a suitable source mechanism. A vertical, liquid-filled glass tube featuring a concentric diameter change was used to provide canonical insights into potentially deep or shallow seismic sources. As gas slugs ascend the tube, we observe systematic pressure changes varying with slug size, liquid depth, tube diameter, and liquid viscosity. Gas slugs undergoing an abrupt flow pattern change upon entering a section of significantly increased tube diameter induce a transient pressure decrease in and above the flare and an associated pressure increase below it, which stimulates acoustic and inertial resonant oscillations. When the liquid flow is not dominantly controlled by viscosity, net vertical forces on the apparatus are also detected. The net force is a function of the magnitude of the pressure transients generated and the tube geometry, which dictates where, and hence when, the traveling pressure pulses can couple into the tube. In contrast to interpretations of related volcano-seismic data, where a single downward force is assumed to result from an upward acceleration of the center of mass in the conduit, our experiments suggest that significant downward forces can result from the rapid deceleration of relatively small volumes of downward-moving liquid. Copyright 2006 by the American Geophysical Union.

  12. On super edge-graceful trees of diameter four

    CERN Document Server

    Krop, E; Raridan, C

    2011-01-01

    In "On the super edge graceful trees of even orders," Chung, Lee, Gao, and Schaffer posed the following problem: Characterize trees of diameter 4 which are super edge-graceful. In this paper, we provide super edge-graceful labelings for all caterpillars and even size lobsters of diameter 4 which permit such labelings. We also provide super edge-graceful labelings for several families of odd size lobsters of diameter 4.

  13. k-Diameter of Circulant Graph with Degree 3

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xian-di; LI Man-li

    2005-01-01

    Parameters k-distance and k-diameter are extension of the distance and the diameter in graph theory. In this paper, the k-distance dk (x,y) between the any vertices x andy is first obtained in a connected circulant graph G with order n (n is even) and degree 3 by removing some vertices from the neighbour set of the x. Then, the k-diameters of the connected circulant graphs with order n and degree 3 are given by using the k-diameter dk (x, y).

  14. Red blood cell decreases of microgravity

    Science.gov (United States)

    Johnson, P. C.

    1985-01-01

    Postflight decreases in red blood cell mass (RBCM) have regularly been recorded after exposure to microgravity. These 5-25 percent decreases do not relate to the mission duration, workload, caloric intake or to the type of spacecraft used. The decrease is accompanied by normal red cell survivals, increased ferritin levels, normal radioactive iron studies, and increases in mean red blood cell volume. Comparable decreases in red blood cell mass are not found after bed rest, a commonly used simulation of the microgravity state. Inhibited bone marrow erythropoiesis has not been proven to date, although reticulocyte numbers in the peripheral circulation are decreased about 50 percent. To date, the cause of the microgravity induced decreases in RBCM is unknown. Increased splenic trapping of circulating red blood cells seem the most logical way to explain the results obtained.

  15. Guided proliferation and bone-forming functionality on highly ordered large diameter TiO2 nanotube arrays.

    Science.gov (United States)

    Zhang, Ruopeng; Wu, Hongliu; Ni, Jiahua; Zhao, Changli; Chen, Yifan; Zheng, Chengjunyi; Zhang, Xiaonong

    2015-08-01

    The significantly enhanced osteoblast adhesion, proliferation and alkaline phosphatase (ALP) activity were observed on TiO2 nanotube surface in recent studies in which the scale of nanotube diameter was restricted under 100 nm. In this paper, a series of highly ordered TiO2 nanotube arrays with larger diameters ranging from 150 nm to 470 nm were fabricated via high voltage anodization. The behaviors of MC3T3-E1 cells in response to the diameter-controlled TiO2 nanotubes were investigated. A contrast between the trend of proliferation and the trend of cell elongation was observed. The highest cell elongation (nearly 10:1) and the lowest cell number were observed on the TiO2 nanotube arrays with 150 nm diameter. While, the lowest cell elongation and highest cell number were achieved on the TiO2 nanotube arrays with 470 nm diameter. Furthermore, the ALP activity peaked on the 150 nm diameter TiO2 nanotube arrays and decreased dramatically with the increase of nanotube diameter. Thus a narrow range of diameter (100-200 nm) that could induce the greatest bone-forming activity is determined. It is expected that more delicate design of orthopedic implant with regional abduction of cell proliferation or bone forming could be achieved by controlling the diameter of TiO2 nanotubes. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Small-Volume Injections: Evaluation of Volume Administration Deviation From Intended Injection Volumes.

    Science.gov (United States)

    Muffly, Matthew K; Chen, Michael I; Claure, Rebecca E; Drover, David R; Efron, Bradley; Fitch, William L; Hammer, Gregory B

    2017-10-01

    In the perioperative period, anesthesiologists and postanesthesia care unit (PACU) nurses routinely prepare and administer small-volume IV injections, yet the accuracy of delivered medication volumes in this setting has not been described. In this ex vivo study, we sought to characterize the degree to which small-volume injections (≤0.5 mL) deviated from the intended injection volumes among a group of pediatric anesthesiologists and pediatric postanesthesia care unit (PACU) nurses. We hypothesized that as the intended injection volumes decreased, the deviation from those intended injection volumes would increase. Ten attending pediatric anesthesiologists and 10 pediatric PACU nurses each performed a series of 10 injections into a simulated patient IV setup. Practitioners used separate 1-mL tuberculin syringes with removable 18-gauge needles (Becton-Dickinson & Company, Franklin Lakes, NJ) to aspirate 5 different volumes (0.025, 0.05, 0.1, 0.25, and 0.5 mL) of 0.25 mM Lucifer Yellow (LY) fluorescent dye constituted in saline (Sigma Aldrich, St. Louis, MO) from a rubber-stoppered vial. Each participant then injected the specified volume of LY fluorescent dye via a 3-way stopcock into IV tubing with free-flowing 0.9% sodium chloride (10 mL/min). The injected volume of LY fluorescent dye and 0.9% sodium chloride then drained into a collection vial for laboratory analysis. Microplate fluorescence wavelength detection (Infinite M1000; Tecan, Mannedorf, Switzerland) was used to measure the fluorescence of the collected fluid. Administered injection volumes were calculated based on the fluorescence of the collected fluid using a calibration curve of known LY volumes and associated fluorescence.To determine whether deviation of the administered volumes from the intended injection volumes increased at lower injection volumes, we compared the proportional injection volume error (loge [administered volume/intended volume]) for each of the 5 injection volumes using a linear

  17. Accuracy of Inferior Vena Cava, Aorta, and Jugular Vein Ultrasonographic Diameters in Identifying Pediatric Dehydration

    Directory of Open Access Journals (Sweden)

    Hamid Kariman

    2015-10-01

    Full Text Available Introduction: Evaluating intravascular volume is an important but complicated matter in management of critically ill patients, especially in children. Although invasive techniques have the ability to accurately estimate the intravascular volume, but they have dangerous side effects. Therefore, the present study was designed with the aim of comparing the diagnostic accuracy of sonographic diameters of inferior vena cava (IVC, aorta, internal jugular vein (IJV, and IVC/aorta ratio in identifying pediatric dehydration in children presented to the emergency department (ED. Methods: The present prospective cross-sectional study was carried out with the aim of determining the diagnostic accuracy of sonographic diameters of IVC, IJV, and aorta, in estimation of dehydration rate for children presented to the ED with mild to moderate dehydration. Their screening performance characteristics, such as area under the ROC curve, sensitivity and specificity, were calculated and used for this purpose. The data were analyzed using STATA 11.0 and 0.05 was considered as significance level. Results: In the end, 54 patients were enrolled in the study (57.4% male, mean age of 4.9 ± 2.7 years. Area under the ROC curve for IVC in diagnosis of moderate dehydration in sagittal and transverse planes were 0.775 (95% CI: 0.65 – 0.91 and 0.8086 (95%CI: 0.96 – 0.93, respectively. In addition, the diameter of aorta in this regard were 0.658 (95%CI: 0.51 – 0.81 for the sagittal and 0.7126 (95% CI: 0.57 – 0.86 for the transverse plane. IJV diameter had an area under the curve of 0.7332 (95% CI: 0.59 – 0.88. Comparing the area under the ROC curves for the studied parameters showed that IVC diameter in the sagittal (p = 0.004 and transverse (p < 0.001 planes is a better index for diagnosis of moderate dehydration. Conclusion: Based on the findings of the present study, it seems that IJV, IVC, and aorta diameters are not very accurate for determining the condition of

  18. Mean particle diameters: from statistical definition to physical understanding

    NARCIS (Netherlands)

    Alderliesten, M.

    2008-01-01

    Mean particle diameters are important for the science of particulate systems. This thesis deals with a definition system for these mean diameters, called Moment-Ratio (M-R) definition system, and provides a general statistical and physical basis. Also, the current DIN/ISO definition system is discus

  19. Effect of flow rate on diameter of electrospun nanoporous fibers

    Directory of Open Access Journals (Sweden)

    Tang Xiao-Peng

    2014-01-01

    Full Text Available The effect of flow rate on the diameter of the charged jet in the electrospinning process is studied theoretically. The obtained theoretical results offer in-depth physical understanding and mechanism of nanoporous fibers. It also reveals that the morphology and diameter of nanoporous microspheres can be controlled by the flow rate.

  20. Guided proliferation and bone-forming functionality on highly ordered large diameter TiO{sub 2} nanotube arrays

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ruopeng; Wu, Hongliu; Ni, Jiahua, E-mail: jiahua.ni@sjtu.edu.cn; Zhao, Changli; Chen, Yifan; Zheng, Chengjunyi; Zhang, Xiaonong, E-mail: xnzhang@sjtu.edu.cn

    2015-08-01

    The significantly enhanced osteoblast adhesion, proliferation and alkaline phosphatase (ALP) activity were observed on TiO{sub 2} nanotube surface in recent studies in which the scale of nanotube diameter was restricted under 100 nm. In this paper, a series of highly ordered TiO{sub 2} nanotube arrays with larger diameters ranging from 150 nm to 470 nm were fabricated via high voltage anodization. The behaviors of MC3T3-E1 cells in response to the diameter-controlled TiO{sub 2} nanotubes were investigated. A contrast between the trend of proliferation and the trend of cell elongation was observed. The highest cell elongation (nearly 10:1) and the lowest cell number were observed on the TiO{sub 2} nanotube arrays with 150 nm diameter. While, the lowest cell elongation and highest cell number were achieved on the TiO{sub 2} nanotube arrays with 470 nm diameter. Furthermore, the ALP activity peaked on the 150 nm diameter TiO{sub 2} nanotube arrays and decreased dramatically with the increase of nanotube diameter. Thus a narrow range of diameter (100–200 nm) that could induce the greatest bone-forming activity is determined. It is expected that more delicate design of orthopedic implant with regional abduction of cell proliferation or bone forming could be achieved by controlling the diameter of TiO{sub 2} nanotubes. - Highlights: • Improved anodization methods leading to more ordered large diameter TiO{sub 2} nanotubes • Significantly enhanced ALP activity was observed on 150 nm diameter TiO{sub 2} nanotubes. • The highest cell density was observed on 470 nm diameter TiO{sub 2} nanotube arrays. • Similar cell response was observed on the amorphous and anatase phased nanotube surface.

  1. Stress Wave Dispersion in Large-Diameter SHPB and Its Manifold Manifestations

    Institute of Scientific and Technical Information of China (English)

    王永刚; 王礼立

    2004-01-01

    The wave dispersion due to the lateral inertia in the split Hopkinson pressure bar(SHPB) with large-diameter bar is numerically analyzed by means of the LS-DYNA3D code. The results show that, ① the stress distribution across the bar section is non-uniform along the radius direction and such non-uniformity depends on the material Poisson ratio and propagation distance; ② with increasing the bar diameter, the high frequency oscillations are notably enhanced and the rise time of wave front becomes longer, meanwhile the amplitude of the stress wave attenuates; ③ with decreasing the rise time of wave front, the wave dispersion markedly enhanced, particularly in the large diameter bar. All of those effects should not be neglected in order to obtain accurate results by the SHPB test.

  2. Assymetry of temporal artery diameters during spontaneous attacks of cluster headache

    DEFF Research Database (Denmark)

    Nielsen, Thue H; Tfelt-Hansen, Peer; Iversen, Helle K

    2009-01-01

    BACKGROUND: Cluster headache is characterized by strictly unilateral head pain associated with symptoms of cranial autonomic features. Transcranial Doppler studies showed in most studies a bilateral decreased blood flow velocity in the middle cerebral artery. OBJECTIVE: To investigate whether...... there is a bilateral or unilateral extracranial vasodilation during spontaneous cluster headache attacks. DESIGN AND METHODS: In 9 cluster headache patients, we investigated the luminal diameter of the superficial temporal artery with ultrasound on the headache and headache-free side during and outside cluster...... headache attacks. RESULTS: During cluster headache attacks, the diameter of the superficial temporal artery on the painful side was greater, 1.48 mm, than the diameter on the nonheadache site, 1.14 mm (P

  3. Reliable Diameter Control of Carbon Nanotube Nanobundles Using Withdrawal Velocity

    Science.gov (United States)

    Shin, Jung Hwal; Kim, Kanghyun; An, Taechang; Choi, WooSeok; Lim, Geunbae

    2016-09-01

    Carbon nanotube (CNT) nanobundles are widely used in nanoscale imaging, fabrication, and electrochemical and biological sensing. The diameter of CNT nanobundles should be controlled precisely, because it is an important factor in determining electrode performance. Here, we fabricated CNT nanobundles on tungsten tips using dielectrophoresis (DEP) force and controlled their diameters by varying the withdrawal velocity of the tungsten tips. Withdrawal velocity pulling away from the liquid-air interface could be an important, reliable parameter to control the diameter of CNT nanobundles. The withdrawal velocity was controlled automatically and precisely with a one-dimensional motorized stage. The effect of the withdrawal velocity on the diameter of CNT nanobundles was analyzed theoretically and compared with the experimental results. Based on the attachment efficiency, the withdrawal velocity is inversely proportional to the diameter of the CNT nanobundles; this has been demonstrated experimentally. Control of the withdrawal velocity will play an important role in fabricating CNT nanobundles using DEP phenomena.

  4. Superresolution measurement of nanofiber diameter by modes beating

    Science.gov (United States)

    Fenton, E. F.; Solano, P.; Hoffman, J. E.; Orozco, L. A.; Rolston, S. L.; Fatemi, F. K.

    2016-05-01

    Nanofibers are becoming an important tool in quantum information technologies for coupling photonics systems to atomic systems. Nondestructive techniques for characterizing these nanofibers prior to integration into an apparatus are desirable. In this work, we probe the light propagating in a fused silica optical nanofiber (750-nm-diameter) by coupling it evanescently to a 6- μm-diameter microfiber that is scanned along the nanofiber length. This technique is capable of observing all possible beat lengths among different propagating modes. The beat lengths are strongly dependent on the nanofiber diameter and refractive index of the fiber. The steep dependence has enabled measurements of the fiber diameter with sub-Angstrom sensitivity. The diameter extracted from the beat length measurements agrees with a measurement made using scanning electron microscopy. Work supported by NSF.

  5. Decreased Lamina Cribrosa Beam Thickness and Pore Diameter Relative to Distance From the Central Retinal Vessel Trunk

    OpenAIRE

    Wang, Bo; Lucy, Katie A.; Schuman, Joel S.; Sigal, Ian A.; Richard A Bilonick; Kagemann, Larry; Kostanyan, Tigran; Lu, Chen; Liu, Jonathan; Grulkowski, Ireneusz; Fujimoto, James G.; Ishikawa, Hiroshi; Wollstein, Gadi

    2016-01-01

    Purpose: To investigate how the lamina cribrosa (LC) microstructure changes with distance from the central retinal vessel trunk (CRVT), and to determine how this change differs in glaucoma. Methods: One hundred nineteen eyes (40 healthy, 29 glaucoma suspect, and 50 glaucoma) of 105 subjects were imaged using swept-source optical coherence tomography (OCT). The CRVT was manually delineated at the level of the anterior LC surface. A line was fit to the distribution of LC microstructural par...

  6. Effects of diameter, length, and circuit pressure on sound conductance through endotracheal tubes.

    Science.gov (United States)

    Räsänen, Jukka O; Rosenhouse, Giora; Gavriely, Noam

    2006-07-01

    We evaluated the acoustic frequency response of endotracheal tubes (ETs) to assess their effect on respiratory system sound transmission studies. White noise 150-3300 Hz was introduced into 4.0-, 6.0-, and 8.0-mm ETs and recorded at their proximal and distal ends. Four tubes of each size were studied at their original and normalized lengths, in straight and bent configurations, and at circuit pressures from 0 to 20 cmH2O. The characteristics of the sound transmission were compared using an analysis of variance for repeated measures. The average transmission amplitude varied directly with tube diameter. The position of peaks and troughs on the amplitude frequency distribution depended on tube length but not on tube diameter. The angle of the phase-frequency plot correlated well with the length of the tube and was independent of its diameter. A 90 degrees bend in the tube had no effect on its sound transmission. Increasing the circuit pressure above ambient modified the frequency response only if volume changes occurred in the test lung. When used to conduct sound into the respiratory system an ET affects the incident signal predictably depending on its length and diameter but not on its curvature or circuit pressure.

  7. Packing Effect of Excluded Volume on Hard-Sphere Colloids

    Institute of Scientific and Technical Information of China (English)

    肖长明; 金国钧; 马余强

    2001-01-01

    We apply the principle of maximum entropy to consider the excluded volume effect on the phase separation of binary mixtures consisting of hard spheres with two different diameters. We show that a critical volume fraction of hard spheres exists locating the packing of large spheres. In particular, through numerical calculation, we have found that the critical volume fraction becomes lower when the ratio α = σ1/σ2 of large-to-small sphere diameters increases, but becomes higher when the ratio of the large sphere volume fraction to the total volume fraction of large and small spheres increases.

  8. Diameter of common bile duct: what are the predicting factors?

    Directory of Open Access Journals (Sweden)

    Atoosa Adibi

    2007-07-01

    Full Text Available

    BACKGROUND: This was a study to determine the correlation between the common bile duct (CBD diameter and demographic data, fasting, and the history of opium addiction.
    METHODS: This was a cross-sectional study on 375 patients (>16 years old including 219 females and 156 males. They had no evident hepatobiliary or pancreatic disease and underwent abdominopelvic ultrasonography for measurement of their CBD diameter. Ultrasound (US was performed to measure CBD diameter at the porta hepatis (proximal part and behind the head of the pancreas (distal part. Correlation coefficients for the association between CBD diameter and predictive factors were calculated. t-test was applied to compare the means between the groups.
    RESULTS: The mean CBD diameter (1 standard deviation, in proximal and distal parts were 3.64 mm (±1.2 and 3.72 mm (±1.2, respectively. The CBD diameters (proximal and distal were significantly (P<0.05 correlated with age (r = 0.55 and 0.54, respectively, BMI (r = 0.25 and 0.27, respectively and portal vein diameter (r = 0.24 and 0.22, respectively. Distal diameter of CBD was significantly larger in opium addicts (5.66 ± 2.65 in comparison with non addicts (3.68 ± 1.17, P = 0.04.
    CONCLUSIONS: CBD diameter associates with age, BMI, portal vein diameter and opium addiction. CBD dilatation, if it can not be explained by age, opium usage or large BMI, should be evaluated further to rule out obstruction.
    KEY WORDS: Common bile duct, predicting factors, ultrasonography.

  9. Effect of Anodic Alumina Oxide Pore Diameter on the Crystallization of Poly(butylene adipate).

    Science.gov (United States)

    Sun, Xiaoli; Fang, Qunqun; Li, Huihui; Ren, Zhongjie; Yan, Shouke

    2016-04-05

    Poly(butylene adipate) (PBA) was infiltrated into the anodic alumina oxide (AAO) templates with the pore diameter of around 30, 70, and 100 nm and PBA nanotubes with different diameters were prepared. The crystallization and phase transition behavior of the obtained PBA nanotubes capped in the nanopores have been explored by using X-ray diffraction and differential scanning calorimetry. Only α-PBA crystals form in the bulk sample during nonisothermal crystallization. By contrast, predominant β-PBA crystals form in the AAO templates. The β-PBA crystals formed in the nanopores with pore diameter less than 70 nm prefer to adopt an orientation with their b-axis parallel to the long axis of the pore. During the melt recrystallization, it was found that the critical temperature (Tβ), below which pure β-crystals form, is 20 °C for bulk PBA. It drops down significantly with the pore diameter for the PBA in the AAO template. Moreover, the β-crystals in the porous template exhibit larger lattice parameters compared with the bulk crystals. By monitoring the change of β-crystals in the heating process, it was found that β-crystals in the AAO template with the pore diameter of 30 nm (D30) melt directly while the β-crystals transform to α-crystals in the template with the pore diameter of 100 nm (D100). The intensity of (020) Bragg peak of β-crystals decreases at a similar rate in both D30 and D100 but disappears at a relatively lower temperature in D30. On the other hand, the β(110) peak intensity of β-PBA crystals formed in the D100 template decreases first at slower rate before α crystals appear, and then at a faster rate once the β to α phase transition takes place.

  10. Axial variation of basic density of Araucaria angustifolia wood in different diameter classes

    Directory of Open Access Journals (Sweden)

    Rômulo Trevisan

    Full Text Available ABSTRACT: The study of the wood characteristics is of fundamental importance for the correct use of this raw material and, among its properties, the basic density is a major, being reference in the quality of this material. This study aimed to evaluate the axial variation of basic density of the wood of Araucaria angustifolia (Bertoloni O. Kuntze in different diameter classes. For this, three trees were selected in six diameter classes, called class 1 (20-30cm, class 2 (30.1-40cm, class 3 (40.1-50cm, class 4 (50.1-60cm, class 5 (60.1-70cm and class 6 (70.1-80cm. From each individual sampled was withdrawn a disc at 0.1m (base, 25, 50, 75 and 100% of the height of the first live branch and in the diameter at 1.30m from the ground (DBH, which were used for determining basic density. The weighted average basic density was equal to 0.422g cm-3 and, regardless of the diameter class analyzed, this property decreased in the axial direction. Diameter induced variation of basic density, but has not been verified a positive or negative systematic tendency in relation to the sampled interval.

  11. The effect of nozzle-exit-channel shape on resultant fiber diameter in melt-electrospinning

    Science.gov (United States)

    Esmaeilirad, Ahmad; Ko, Junghyuk; Rukosuyev, Maxym V.; Lee, Jason K.; Lee, Patrick C.; Jun, Martin B. G.

    2017-01-01

    In recent decades, electrospinning using a molten poly (ε-caprolactone) resin has gained attention for creating fibrous tissue scaffolds. The topography and diameter control of such electrospun microfibers is an important issue for their different applications in tissue engineering. Charge density, initial nozzle-exit-channel cross-sectional area, nozzle to collector distance, viscosity, and processing temperature are the most important input parameters that affect the final electrospun fiber diameters. In this paper we will show that the effect of nozzle-exit-channel shape is as important as the other effective parameters in a resultant fiber diameter. However, to the best of our knowledge, the effect of nozzle-exit-channel shapes on a resultant fiber diameter have not been studied before. Comparing rectangular and circular nozzles with almost the same exit-channel cross-sectional areas in a similar processing condition showed that using a rectangular nozzle resulted in decreasing final fiber diameter up to 50%. Furthermore, the effect of processing temperature on the final fiber topography was investigated.

  12. PHOS Experiment: Thermal Response of a Large Diameter Pulsating Heat Pipe on Board REXUS-18 Rocket

    Science.gov (United States)

    Creatini, F.; Guidi, G. M.; Belfi, F.; Cicero, G.; Fioriti, D.; Di Prizio, D.; Piacquadio, S.; Becatti, G.; Orlandini, G.; Frigerio, A.; Fontanesi, S.; Nannipieri, P.; Rognini, M.; Morganti, N.; Filippeschi, S.; Di Marco, P.; Fanucci, L.; Baronti, F.; Mameli, M.; Marengo, M.; Manzoni, M.

    2015-09-01

    In the present work, the results of two Closed Loop Pulsating Heat Pipes (CLPHPs) tested on board REXUS-1 8 sounding rocket in order to get experimental data over a relatively broad reduced gravity period (about 90 s) are thoroughly discussed. The CLPHPs are partially filled with refrigerant FC-72 and have, respectively, an inner tube diameter larger (3 .0 mm) and slightly smaller (1 .6 mm) than a critical diameter defined on Earth gravity conditions. On ground, the small diameter CLPHP works as a real Pulsating Heat Pipe (PHP): the typical capillary slug flow pattern forms inside the device and the heat exchange is triggered by self-sustained thermally driven oscillations of the working fluid. Conversely, the large diameter CLPHP behaves like a two-phase thermosyphon in vertical position while does not operate in horizontal position as the working fluid stratifies within the tube and surface tension is not able to balance buoyancy. Then, the idea to test the CLPHPs under reduced gravity conditions: as soon as gravity reduces, buoyancy becomes less intense and the typical capillary slug flow pattern can also forms within a tube with a larger diameter. Moreover, this allows to increase the heat transfer rate and, consequently, to decrease the overall thermal resistance. Even though it was not possible to experience the expected reduced gravity conditions due to a failure of the yo-yo de-spin system, the thermal response to the peculiar acceleration field (hyper-gravity) experienced on board are thoroughly described.

  13. Diameter limitation in growth of III-Sb-containing nanowire heterostructures.

    Science.gov (United States)

    Ek, Martin; Borg, B Mattias; Johansson, Jonas; Dick, Kimberly A

    2013-04-23

    The nanowire geometry offers significant advantages for exploiting the potential of III-Sb materials. Strain due to lattice mismatch is efficiently accommodated, and carrier confinement effects can be utilized in tunneling and quantum devices for which the III-Sb materials are of particular interest. It has however proven difficult to grow thin (below a few tens of nanometers), epitaxial III-Sb nanowires, as commonly no growth is observed below some critical diameter. Here we explore the processes limiting the diameter of III-Sb nanowires in a model system, in order to develop procedures to control this effect. The InAs-GaSb heterostructure system was chosen due to its great potential for tunneling devices in future low-power electronics. We find that with increasing growth temperature or precursor partial pressures, the critical diameter for GaSb growth on InAs decreases. To explain this trend we propose a model where the Gibbs-Thomson effect limits the Sb supersaturation in the catalyst particle. This understanding enabled us to further reduce the nanowire diameter down to 32 nm for GaSb grown on 21 nm InAs stems. Finally, we show that growth conditions must be carefully optimized for these small diameters, since radial growth increases for increased precursor partial pressures beyond the critical values required for nucleation.

  14. Optimization of maxblend impeller diameter in high viscous fluid by CFD%高黏体系中最大叶片式搅拌桨直径的CFD优化

    Institute of Scientific and Technical Information of China (English)

    王令闪; 苏红军; 徐世艾

    2011-01-01

    The distribution of velocity, dead-zone volume, shear rates, apparent viscosity and overall flow status with different impeller diameters in tanks were studied by means of computational fluid dynamics ( CFD) in order to optimize the diameter of the maxblend impeller in high viscous xanthan gum solutions. The result shows that the circulation zone volume and average velocity in tank are increased, at the same time the uniformity of velocity distribution is improved, which leads to obvious decrease of dead volume in tank as the impeller diameter increases under the condition of constant agitation power. The optimum diameter of maxblend impeller is 0. 276 m for the studied system. When the impeller diameter is continued to increase more than 0. 276 m, the change of dead volume in tank is inconspicuous, and the shear performance of maxblend impeller evidently deteriorates.%以黄原胶溶液为研究体系,借助于计算流体力学( CFD)方法研究了采用不同直径的最大叶片式搅拌桨时釜内流体速率分布、死区体积、剪切速率、表观黏度和总体流体状况等参数.研究发现:在保持功率不变的前提下,随着桨径的增大,釜内循环区影响范围变广,全釜平均液相速率逐渐增加,速度分布均匀度有所提高,死区体积明显下降.对于研究的搅拌体系,最大叶片式桨适宜直径为0.276 m.当桨径再继续增大直径时,釜内死区减少不明显,同时搅拌桨的剪切性能恶化.

  15. Diameter and position effect determination of diaphragm on hybrid rocket motor

    Science.gov (United States)

    Sun, Xingliang; Tian, Hui; Cai, Guobiao

    2016-09-01

    This study is aimed to determine and better reveal the mixture enhancement and regression rate distribution of hybrid rocket motor with diaphragm by numerical approach. A numerical model based on the computational fluid dynamics software is built to simulate the flow and combustion inside the motor. Four firing tests of the motor, including one without diaphragm and three with diaphragm, are conducted on a standard experimental system and also used as a reference for numerical simulation, the consistency between the simulation and experiment demonstrates that the numerical approach is an effective method to study the diaphragm effect on the motor performance. The flow field characteristic and regression rate distribution inside the hybrid rocket motor are then calculated to analyze the effect of position and diameter of the diaphragm. The results indicate that the diaphragm almost have no effect on the regression rate before it. However, the regression rate after the diaphragm has a strong dependence on the position and diameter of the diaphragm. As the diameter decreases and the position moves backward, the regression rate increases larger and larger, this is mainly due to the augmentation of the eddy generated by the diaphragm, which enhances the heat feedback transferred to the grain surface. When the diameter of diaphragm located at middle of grain decreases from 50 mm to 20 mm, regression rate is increased from 0.30 mm/s to 0.57 mm/s. The use of the diaphragm does cause a combustion efficiency improvement; the maximum combustion efficiency is enhanced to 98.9% from lower than 90% of the motor with no diaphragm. The increasing amplitude displays a square relation with the diameter decrease, since the entrainment of the eddy make the reactants mix sufficiently to release more energy inside the motor.

  16. Association between axial length and horizontal and vertical globe diameters.

    Science.gov (United States)

    Jonas, Jost B; Ohno-Matsui, Kyoko; Holbach, Leonard; Panda-Jonas, Songhomitra

    2017-02-01

    To assess relationships between axial length and the horizontal and vertical globe diameters. The study consisted of enucleated human eyes. The horizontal, vertical, and sagittal diameters were measured. The study included 135 globes removed because of malignant uveal melanoma (111 globes) or end-stage painful glaucoma (n = 24 eyes). Mean axial, horizontal, and vertical diameters were 24.6 ± 2.6 mm (range: 20-35 mm), 23.7 ± 1.4 mm (range: 21-29 mm) and 23.7 ± 1.4 mm (range: 20-29 mm) respectively. The horizontal diameter and vertical diameter did not differ significantly (P = 0.92), while both were significantly (P globe diameter (P globe diameter = 0.84 × horizontal globe diameter + 3.69). The axial diameter was significantly (P 24 mm, the horizontal and vertical globe diameter increased by a lower amount of 0.19 and 0.21 mm, respectively, for each mm increase in axial diameter. Myopic enlargement of the globe beyond an axial length of 24 mm takes place predominantly in the sagittal axis, leading to a change in the globe form from a sphere to an elongated form. It fits with the notion that myopic elongation may occur by an elongation of the eye walls in regions close to the globe's equator.

  17. Challenges in Mechanization Efforts of Small Diameter Eucalyptus Harvesting Operations with a Low Capacity Running Skyline Yarder in Southern China

    Directory of Open Access Journals (Sweden)

    Stephan Hoffmann

    2015-08-01

    Full Text Available This case study examines the performance of the Igland Hauler employed in small diameter Eucalyptus clear-cut operations in Guangxi, China. A yarding crew of eight persons was monitored by a snap back elemental time study for 19.23 SMH (scheduled machine hours, with 159 yarding cycles and a yarded log volume at landing of 49.4 m³ solid over bark. A gross-productivity of 2.50 m³/SMH and net-productivity of 5.06 m³/PMH0 (productive machine hours excluding delay times was achieved, leading to a machine utilization rate of 49.5%. The costs of the yarder and associated overhead as well as the personnel costs of a large crew with eight people sum up to extraction costs of 50.24 USD/m³. The high costs make it difficult to compete economically with the locally common manual extraction system as long as abundant labor at a low hourly rate is available in the region. Further performance improvement through skill development, but also technical and organizational system modification in conjunction with rising wages and decreasing labor force in rural primary production will determine the justification of employing such yarding systems. However, new silvicultural regimes with extended rotations and supply requirements of the forest products industry in China demand new operational systems.

  18. Diameter-dependent thermodynamic and elastic properties of metallic nanoparticles

    Science.gov (United States)

    Chandra, Jeewan; Kholiya, Kuldeep

    2015-04-01

    A simple theoretical model has been proposed to study the diameter-dependent properties of metallic nanoparticles, i.e. Ag, Au, Al, Ni, Pb, Cu and Fe. The diameter-dependent thermodynamic properties includes melting temperature, Debye temperature, evaporation temperature, melting enthapy and melting entropy. The model is also extended to study the diameter-dependent elastic properties including bulk modulus, Young's modulus and thermal expansion coefficient. On comparison with available experimental findings and other theoretical approaches, the results obtained with the present formulation depict a close agreement and demonstrate the validity of the method proposed in the present paper.

  19. Measurement of fetal biparietal diameter in owl monkeys (Aotus nancymaae).

    Science.gov (United States)

    Schuler, A Michele; Brady, Alan G; Tustin, George W; Parks, Virginia L; Morris, Chris G; Abee, Christian R

    2010-09-01

    Owl monkeys are New World primates frequently used in biomedical research. Despite the historical difficulty of breeding owl monkeys in captivity, several productive owl monkey breeding colonies exist currently. The animals in the colony we describe here are not timed-pregnant, and determination of gestational age is an important factor in prenatal care. Gestational age of human fetuses is often determined by using transabdominal measurements of fetal biparietal diameter. The purpose of this study was to correlate biparietal diameter measurements with gestational age in owl monkeys. We found that biparietal diameter can be used to accurately predict gestational age in owl monkeys.

  20. The Non-Homologous Nature of Solar Diameter Variations

    CERN Document Server

    Sofia, S; Demarque, P; Li, L; Thuillier, G; Sofia, Sabatino; Basu, Sarbani; Demarque, Pierre; Li, Linghuai; Thuillier, Gerard

    2005-01-01

    We show in this paper that the changes of the solar diameter in response to variations of large scale magnetic fields and turbulence are not homologous. For the best current model, the variation at the photospheric level is over 1000 times larger than the variation at a depth of 5 Mm, which is about the level at which f-mode solar oscillations determine diameter variations. This model is supported by observations that indicate larger diameter changes for high degree f-modes than for low degree f-modes, since energy of the former are concentrated at shallower layers than the latter.

  1. Relationship of rolling bearing stiffness with diameter of roller

    Institute of Scientific and Technical Information of China (English)

    郭茂林; 王刚; 张瑞

    2002-01-01

    The theoretical formula of roller bearing stiffness is induced and compared with its empirical formula.In the experience formula the stiffness of roller bearing has nothing to do with the roller diameter. The relation-ship of roller bearing stiffness with roller diameter was studied using Hz contacting theory. It is concluded thatconclusion in experience formula is only approximate result of data processing under special conditions, and therelation between stiffness of roller bearing and roller diameter must be taken into consideration while designingor selecting roller bearings.

  2. Effect of Graphite Nodule Diameter on Water Embrittlement of Austempered Ductile Iron

    Institute of Scientific and Technical Information of China (English)

    CAI Qi-zhou; WEI Bo-kang; TANAKA Yuichi

    2005-01-01

    Effects of graphite nodule diameter on the water embrittlement of austempered ductile iron (ADI) is studied. The water embrittlement mechanism is discussed. Due to water adhesion, local embrittlement occurs on the surface of ADI specimen, resulting in early fracture and significant reduction in tensile strength and elongation. The water embrittlement is the cracking of stress induced martensite formed during tensile deformation caused by hydrogen diffusion decomposed from water and as a result tensile strength and elongation of ADI are remarkably reduced. The segregation of alloying elements in ductile iron is weakened with decreasing nodule diameter, reducing the residual austenite in grain boundaries, then decreasing the amount of stress induced martensite during tensile plastic deformation and finally restraining ADI water embrittlement.

  3. Measured Performance of a Varied Airflow Small-Diameter Duct System

    Energy Technology Data Exchange (ETDEWEB)

    Poerschke, Andrew [IBACOS, Inc., Pittsburgh, PA (United States)

    2017-03-16

    This study tests the performance of a variable airflow small-diameter duct heating, ventilation, and air conditioning (HVAC) system in a new construction unoccupied low-load test house in Pittsburgh, Pennsylvania. The duct system was installed entirely in conditioned space and was operated from the winter through summer seasons. Measurements were collected on the in-room temperatures and energy consumed by the air handler and heat pump unit. Operation modes with three different volumes of airflow were compared to determine the ideal airflow scenario that maximizes room-to-room thermal uniformity while minimizing fan energy consumption. Black felt infrared imagery was used as a measure of diffuser throw and in-room air mixing. Measured results indicate the small-diameter, high velocity airflow system can provide comfort under some conditions. Solar heat gains resulted in southern rooms drifting beyond acceptable temperature limits. Insufficient airflow to some bedrooms also resulted in periods of potential discomfort. Homebuilders or HVAC contractors can use these results to assess whether this space conditioning strategy is an attractive alternative to a traditional duct system. The team performed a cost analysis of two duct system configurations: (1) a conventional diameter and velocity duct system, and (2) the small-diameter duct system. This work applies to both new and retrofit homes that have achieved a low heating and cooling density either by energy conservation or by operation in a mild climate with few heating or cooling degree days. Guidance is provided on cost trade-offs between the conventional duct system and the small-diameter duct system.

  4. Measured Performance of a Varied Airflow Small-Diameter Duct System

    Energy Technology Data Exchange (ETDEWEB)

    Poerschke, Andrew [IBACOS, Inc., Pittsburgh, PA (United States)

    2017-03-01

    This study tests the performance of a variable airflow small-diameter duct heating, ventilation, and air conditioning (HVAC) system in a new construction unoccupied low-load test house in Pittsburgh, Pennsylvania. The duct system was installed entirely in conditioned space and was operated from the winter through summer seasons. Measurements were collected on the in-room temperatures and energy consumed by the air handler and heat pump unit. Operation modes with three different volumes of airflow were compared to determine the ideal airflow scenario that maximizes room-to-room thermal uniformity while minimizing fan energy consumption. Black felt infrared imagery was used as a measure of diffuser throw and in-room air mixing. Measured results indicate the small-diameter, high velocity airflow system can provide comfort under some conditions. Solar heat gains resulted in southern rooms drifting beyond acceptable temperature limits. Insufficient airflow to some bedrooms also resulted in periods of potential discomfort. Homebuilders or HVAC contractors can use these results to assess whether this space conditioning strategy is an attractive alternative to a traditional duct system. The team performed a cost analysis of two duct system configurations: (1) a conventional diameter and velocity duct system, and (2) the small-diameter duct system. This work applies to both new and retrofit homes that have achieved a low heating and cooling density either by energy conservation or by operation in a mild climate with few heating or cooling degree days. Guidance is provided on cost trade-offs between the conventional duct system and the small-diameter duct system.

  5. Building America Case Study: High-Velocity Small-Diameter Duct System, Pittsburgh, Pennsylvania

    Energy Technology Data Exchange (ETDEWEB)

    2017-04-01

    This study tests the performance of a variable airflow small-diameter duct heating, ventilation, and air conditioning (HVAC) system in a new construction unoccupied low-load test house in Pittsburgh, Pennsylvania. The duct system was installed entirely in conditioned space and was operated from the winter through summer seasons. Measurements were collected on the in-room temperatures and energy consumed by the air handler and heat pump unit. Operation modes with three different volumes of airflow were compared to determine the ideal airflow scenario that maximizes room-to-room thermal uniformity while minimizing fan energy consumption. Black felt infrared imagery was used as a measure of diffuser throw and in-room air mixing. Measured results indicate the small-diameter, high velocity airflow system can provide comfort under some conditions. Solar heat gains resulted in southern rooms drifting beyond acceptable temperature limits. Insufficient airflow to some bedrooms also resulted in periods of potential discomfort. Homebuilders or HVAC contractors can use these results to assess whether this space conditioning strategy is an attractive alternative to a traditional duct system. The team performed a cost analysis of two duct system configurations: (1) a conventional diameter and velocity duct system, and (2) the small-diameter duct system. This work applies to both new and retrofit homes that have achieved a low heating and cooling density either by energy conservation or by operation in a mild climate with few heating or cooling degree days. Guidance is provided on cost trade-offs between the conventional duct system and the small-diameter duct system.

  6. Porosity Assessment for Different Diameters of Coir Lignocellulosic Fibers

    Science.gov (United States)

    da Luz, Fernanda Santos; Paciornik, Sidnei; Monteiro, Sergio Neves; da Silva, Luiz Carlos; Tommasini, Flávio James; Candido, Verônica Scarpini

    2017-08-01

    The application of natural lignocellulosic fibers (LCFs) in engineering composites has increased interest in their properties and structural characteristics. In particular, the inherent porosity of an LCF markedly affects its density and the adhesion to polymer matrices. For the first time, both open and closed porosities of a natural LCF, for different diameter ranges, were assessed. Fibers extracted from the mesocarp of the coconut fruit were investigated by nondestructive methods of density measurements and x-ray microtomography (microCT). It was found that, for all diameter ranges, the closed porosity is significantly higher than the open porosity. The total porosity increases with diameter to around 60% for coir fibers with more than 503 μm in diameter. The amount and characteristics of these open and closed porosities were revealed by t test and Weibull statistics as well as by microCT.

  7. Study of Linearly Polarized Light Measuring Fiber Diameter

    Energy Technology Data Exchange (ETDEWEB)

    Liang Hong, E-mail: lianghong@cuc.edu.cn [School of science, Communication University of China 100024 (China)

    2011-02-01

    The letter discusses a new way to measure fiber diameters, studies the theory of measuring fiber radius using this way, carries out numerical simulation based on this and provides experiment method as well.

  8. Eddy sensors for small diameter stainless steel tubes.

    Energy Technology Data Exchange (ETDEWEB)

    Skinner, Jack L.; Morales, Alfredo Martin; Grant, J. Brian; Korellis, Henry James; LaFord, Marianne Elizabeth; Van Blarigan, Benjamin; Andersen, Lisa E.

    2011-08-01

    The goal of this project was to develop non-destructive, minimally disruptive eddy sensors to inspect small diameter stainless steel metal tubes. Modifications to Sandia's Emphasis/EIGER code allowed for the modeling of eddy current bobbin sensors near or around 1/8-inch outer diameter stainless steel tubing. Modeling results indicated that an eddy sensor based on a single axial coil could effectively detect changes in the inner diameter of a stainless steel tubing. Based on the modeling results, sensor coils capable of detecting small changes in the inner diameter of a stainless steel tube were designed, built and tested. The observed sensor response agreed with the results of the modeling and with eddy sensor theory. A separate limited distribution SAND report is being issued demonstrating the application of this sensor.

  9. Improved Design Basis for Laterally Loaded Large Diameter Pile

    DEFF Research Database (Denmark)

    Leth, Caspar Thrane

    of up-to-date facilities has been: Equipment for controlling centrifuge tests, data acquisition, preparation of test samples and equipment for and making of lateral load tests. The present research has been narrowed to investigate the static and cyclic behaviour of stiff piles with a diameter of 1-3 m...... on the structure and the productivity of the turbine. Current design practice for monopiles are based on p-y curves developed for slender piles with a diameter of 0.6 m. The focus on the structure stiffness has entailed a significant research on the soil-structure interaction for large diameter monopiles....... Comparison of the different approaches shows some discrepancy and conflicting statements, but the main findings can be summarized as: • The standard p-y curves are inadequate to describe the behaviour of lateral loaded large diameter rigid piles. • Initial stiffness of the p-y curves is depended...

  10. Pupil diameter reflects uncertainty in attentional selection during visual search

    Directory of Open Access Journals (Sweden)

    Joy J. Geng

    2015-08-01

    Full Text Available Pupil diameter has long been used as a metric of cognitive processing. However, recent advances suggest that the cognitive sources of change in pupil size may reflect LC-NE function and the calculation of unexpected uncertainty in decision processes (Aston-Jones & Cohen, 2005b; Yu & Dayan, 2005. In the current experiments, we explored the role of uncertainty in attentional selection on task-evoked changes in pupil diameter during visual search. We found that task-evoked changes in pupil diameter were related to uncertainty during attentional selection as measured by reaction time and performance accuracy (Experiments 1-2. Control analyses demonstrated that the results are unlikely to be due to error monitoring or response uncertainty. Our results suggest that pupil diameter can be used as an implicit metric of uncertainty in ongoing attentional selection requiring effortful control processes.

  11. Is ultrasonographically detected nodule diameter concordant with pathological tumor size?

    Science.gov (United States)

    Bilginer, Muhammet Cuneyt; Ozdemir, Didem; Baser, Husniye; Dogan, Hayriye Tatli; Yalcin, Abdussamed; Ersoy, Reyhan; Cakir, Bekir

    2017-06-01

    We aimed to compare preoperative ultrasonographical and postoperative histopathological diameters of differentiated thyroid cancer (DTC) lesions and investigate possible factors that can predict the discordance between two measurements. Data of patients with histopathologically confirmed DTC were reviewed retrospectively. Nodules evaluated by preoperative US were matched with histopathologically examined nodules. Incidental tumors and nodules that can not be matched in US and histopathology reports were excluded. Preoperative US diameter and postoperative histopathological size were compared and percentage difference between two measurements was calculated for each lesion. There were 607 DTC foci in 562 patients. Mean US diameter was significantly higher than histopathological diameter (21.0 ± 15.6 mm vs 17.3 ± 13.6, p size in 444 (73.1%), equal in 15 (2.5%) and lower in 148 (24.4%) nodules. Marginal irregularity was observed in 253 (57%) lesions with US diameter > tumor size and 108 (73%) lesions with US diameter size (p = 0.010). Rate of nodules with peripheral halo was higher in lesions with US diameter > tumor size (30.6% vs 20.3%, p = 0.015). In nodules with US diameter > tumor size, percentage difference was lower in nodules with microcalcification (p = 0.020) and higher in cytologically benign nodules (p size, size in a considerable ratio of DTCs. It might be helpful to consider this discordance while deciding surgical extent in these patients. Copyright © 2017 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

  12. Minimum Orders of Eulerian Oriented Digraphs with Given Diameter

    Institute of Scientific and Technical Information of China (English)

    Yoomi RHO; Byeong Moon KIM; Woonjae HWANG; Byung Chul SONG

    2014-01-01

    A digraph D is oriented if it does not contain 2-cycles. If an oriented digraph D has a directed eulerian path, it is an oriented eulerian digraph. In this paper, when an oriented eulerian digraph D has minimum out-degree 2 and a diameter d, we find the minimum order of D. In addition, when D is 2-regular with diameter 4m (m≥2), we classify the extremal cases.

  13. Clinical study on the changes of the tumor target volume and organs at risk in helical tomotherapy for nasopharyngeal carcinoma

    Institute of Scientific and Technical Information of China (English)

    LU Na; FENG Lin-chun; CAI Bo-ning; HOU Jun; WANG Yun-lai; XIE Chuan-bin

    2012-01-01

    Background Helical tomotherapy (HT) is a new image-guided intensity-modulated radiation therapy (IMRT).The aim of this study was to evaluate the changes in the target volume and organs at risk (OARs) of patients with nasopharyngeal carcinoma (NPC) during helical tomotherapy.Methods Forty-three patients with NPC and treated via HT from March 2008 to January 2010 were reviewed retrospectively.Repeated CT scanning and plan adaptation were conducted at the 20th fraction during radiotherapy.The volumetric differences between the two scans were evaluated for nasopharyngeal tumor and retro- pharyngeal lymph nodes (GTVnx),neck lymph nodes (GTVnd),and parotid glands,as well as the axial diameter of the head.Results The median interval between the two scans was 25 days (23-28 days).The volumetric decrease in GTVnx was 30.1% (median,29.8%) and in GTVnd 41.6% (median,45.9%).The variation in the GTVnd volume was correlated with the weight loss of the patient.The volume of the left parotid gland decreased by 35.5% (median,33.4%) and of the right parotid glands decreased by 36.8% (median,33.5%).The axial diameter of the head decreased by 9.39% (median,9.1%).Conclusions The target volume and OARs of patients with NPC varied considerably during HT.These changes may have potential dosimetric effects on the target volume and/or OARs and influence the clinical outcome.Repeated CT scanning and replanning during the HT for NPC patients with a large target volume or an obvious weight loss are recommended.

  14. [Importance of an automatic measurement base on the first coil diameter in regard to coil embolization of a cerebral aneurysm].

    Science.gov (United States)

    Kuriyama, Takumi; Furukawa, Hajime; Shimizu, Keiji; Oonishi, Kumiko; Sakai, Shinji; Imamura, Hirotoshi; Sakai, Chiaki; Sakai, Nobuyuki

    2012-01-01

    We compared the accuracy in evaluating an unrapture aneurysm between NV and 3D-DSA. In vitro, we evaluated the accuracy in calculating the volume of the Aneurysm model. We compared the diameter of the first coil and estimated the diameter of the Aneurysm. The Aneurysm size calculated by NV resembled the first coil more than the size measured by 3D-DSA. In clinical cases, the measurement of NV is objective; the measurement of 3D-DSA, however, is subjective by person. NV has an automatic measurement that is useful for clinical cases.

  15. INFLUENCE OF ROLL DIAMETERS ON DEFORMATION BEHAVIOUR OF HIGH TEMPERATURE SUPERCONDUCTING TAPE

    Institute of Scientific and Technical Information of China (English)

    LEI Liping; ZHAO Yinghong; ZENG Pan

    2007-01-01

    During plastic process, the material flow is strongly influenced by the contact area between deformed workpiece and die. In rolling process, difference of roll diameter makes the contact area between roll and deformed tape different, which leads to different material flow and the distribution of powder density. A numerical modelling of the first rolling process for 61-filament high temperature superconducting tape is constructed and the influences of roll diameters on deformation behavior of the tape are discussed. It can be found that the BiSrCaCuO (BSCCO) powder in the center of the tape has higher relative density than those in the periphery of the tape during rolling process. With the increase of roll diameter, the length of the contact arc in the roll gap expands which lead to the increasing of transversal strain and the decreasing of the related longitudinal strain. It makes the value of longitudinal strain ratio decrease gradually, which decreases the possibility of occurrence of the transversal shear band, simultaneously it increases the risk of occurrence of longitudinal crack.

  16. Numerical Simulation Study of Influence of Nozzle Entrance Diameter on Jet Performance of Pre-mixed Abrasive Water Jet

    Science.gov (United States)

    Guan, Jinfa; Deng, Songsheng; Jiao, Guangwei; Chen, Ming; Hua, Weixing

    Physical model of cone-cylinder nozzle was established. Based on the CFD software of FLUENT, the flow field about abrasive water jet in cone-cylinder nozzle was simulated by use of standard k-ɛ turbulent model, Lagrange Discrete Phase Model and SIMPLE algorithm. The simulation results show that axial velocity of abrasive particle is always smaller than axial velocity of abrasive particle and increases gradually with the increase of axial distance. Axial static pressure of water decreases gradually with the increase of axial distance. Axial velocity of abrasive particle at the exit of cone-cylinder nozzle decreases with the increase of nozzle entrance diameter. And axial static pressure of water at the entrance of cone-cylinder nozzle decreases with the increase of nozzle entrance diameter. 8mm is selected as an optimal nozzle entrance diameter.

  17. Assessment of the Effect of Blast Hole Diameter on the Number of Oversize Boulders Using ANN Model

    Science.gov (United States)

    Dhekne, Prakash; Pradhan, Manoj; Jade, Ravi Krishnarao

    2016-04-01

    Now-a-days, blasts are planned using large diameter blast holes. The loading density (kg/m) and subsequently the energy available for the breakage of the rockmass increase with the diameter. The in-hole velocity of detonation (VoD) of non-ideal explosive also boosts up with the increase in diameter till the optimum diameter is reached. The increase in the energy content and in-hole VoD cause a sizable effect on the rock fragmentation. The effect can be assessed by counting the number of oversize boulders. This paper explains as to how the technique of artificial neural network modeling was used to predict the number of oversize boulders resulting from ANFO and SME blasts with blast holes of different diameters. The results from ANFO blasts indicated that there was no significant variation in the number of oversize boulders with the diameter whereas a perceptible variation was noticed in case of SME blasts with the change in the diameter. The change in the number of oversize boulders in ANFO blasts was negligible because mean energy factor remained almost same even when the diameter of the blast holes was altered. The decrease in the number of oversize boulders in SME blasts was on account of increase in mean energy factor when the blast hole diameter was increased. The increase in the in-hole VoD due to increase in the diameter of the hole was not found to have an effect on the generation of oversize boulders as this increase was not substantial both in SME and ANFO blasts.

  18. The Inferior Vena Cava Diameter as a Marker of Dry Weight in Chronic Hemodialyzed Patients

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    We have previously reported that the diameter of the inferior vena cava(IVC) reflects the amount of body fluid in hemodialyzed (HD) patients. The present study was undertaken to depict the criteria of IVC diameters for determining dry weight (DW) in anuric HD patients. In healthy subjects, the maximal diameters during quiet expiration (IVCe) and the minimal diameters during quiet inspiration (IVCi) were (16.7±3.2) and (5.7±5.4)mm,respectively (mean±SD).The collapsibility index (CI,1-IVCi/IVCe), which inversely correlates with the central venous pressure,was 0.68±0.29. In anuric HD patients,the IVCe/CI values before and after HD were 14.9±3.2/0.68±0.24 and 8.2±2.3/0.94±0.09, respectively. IVCe decreased proportionally to the amount of ultrafiltration. In HD patients with hypervolemic pulmonary edema, the IVCe and CI values were 22.4±2.9 and 0.22±0.11, respectively. We proposed that IVCe/CI after HD is (8±3)mm/0.9 ± 0.1 as the markers of DW in anuric HD patients and that an IVCe value≥22mm together with a CI≤0.22 implies the warning level of body fluid retention.

  19. Anomalous diameter dependence of thermal transport in ultra-narrow Si nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Karamitaheri, Hossein, E-mail: karami@iue.tuwien.ac.at [Institute for Microelectronics, TU Wien, Gußhausstraße 27-29/E360, A-1040 Wien (Austria); Department of Electrical Engineering, University of Kashan, Kashan, 87317-51167 (Iran, Islamic Republic of); Neophytou, Neophytos, E-mail: neophytou@iue.tuwien.ac.at [Institute for Microelectronics, TU Wien, Gußhausstraße 27-29/E360, A-1040 Wien (Austria); School of Engineering, University of Warwick, Coventry CV4 7AL (United Kingdom); Kosina, Hans, E-mail: kosina@iue.tuwien.ac.at [Institute for Microelectronics, TU Wien, Gußhausstraße 27-29/E360, A-1040 Wien (Austria)

    2014-01-14

    We present atomistic valence force field calculations of thermal transport in Si nanowires of diameters from 12 nm down to 1 nm. We show that as the diameter is reduced, the phonon density-of-states and transmission function acquire a finite value at low frequency, in contrast to approaching zero as in the bulk material. It turns out that this effect results in what Ziman described as the “problem of long longitudinal waves” [J. M. Ziman, Electrons and Phonons: The Theory of Transport Phenomena in Solids (Clarendon, Oxford, 1962)], which states that the thermal conductivity of a material increases as its length is increased due to the vanishing scattering for long-wavelength phonons. We show that this thermal transport improvement also appears in nanowires as their diameter is decreased below D = 5 nm (not only as the length increases), originating from the increase in the density of the long wavevector modes. The observation is present under ballistic transport conditions, and further enhanced with the introduction of phonon-phonon scattering. Because of this, in such ultra-narrow nanowires, as the diameter is reduced, phonon transport is dominated more and more by lower energy phonons with longer mean-free paths. We show that ∼80% of the heat is carried by phonons with energies less than 5 meV, most with mean-free paths of several hundreds of nanometers.

  20. Diameter-dependent bending modulus of individual multiwall boron nitride nanotubes.

    Science.gov (United States)

    Tanur, Adrienne E; Wang, Jiesheng; Reddy, Arava L M; Lamont, Daniel N; Yap, Yoke Khin; Walker, Gilbert C

    2013-04-25

    The mechanical properties of individual multiwall boron nitride nanotubes (MWBNNTs) synthesized by a growth-vapor-trapping chemical vapor deposition method are investigated by a three-point bending technique via atomic force microscopy. Multiple locations on suspended tubes are probed in order to determine the boundary conditions of the supported tube ends. The bending moduli (EB) calculated for 20 tubes with diameters ranging from 18 to 58 nm confirm the exceptional mechanical properties of MWBNNTs, with an average EB of 760 ± 30 GPa. For the first time, the bending moduli of MWBNNTs are observed to increase with decreasing diameter, ranging from 100 ± 20 GPa to as high as 1800 ± 300 GPa. This diameter dependence is evaluated by Timoshenko beam theory. The Young's modulus and shear modulus were determined to be 1800 ± 300 and 7 ± 1 GPa, respectively, for a trimmed data set of 16 tubes. The low shear modulus of MWBNNTs is the reason for the detected diameter-dependent bending modulus and is likely due to the presence of interwall shearing between the crystalline and faceted helical nanotube structures of MWBNNTs.

  1. Hole diameters in pet bottles used for fruit fly capture

    Directory of Open Access Journals (Sweden)

    Maurico Paulo Batistella Pasini

    2015-05-01

    Full Text Available Two experiments were conducted during the period from 31 January to 6 March 2012 in Santa Maria, Rio Grande do Sul State, Brazil to determine the efficiency of different hole diameters in PET trap bottles on pests in guava and persimmon orchards. In a randomised block design in a factorial scheme, we assessed the average number adults of Anastrepha fraterculus, Ceratitis capitata (Diptera: Tephitidae and Zaprionus indianus (Diptera: Drosophilidae infruits thatemerged in two situations (in the plant and on the soil; we also assessed the number of captured adults in trap bottlesunder two conditions, different hole diameters and different days after placement of the attractive solution. Smaller diameter sizescaptured more A. fraterculus, C. capitata and Z. indianusadults. The 1.0 cm diameter was the most efficient hole size in reducing the adult emergence of Tephritidae to Z. indianus, whereas the smallest diameter hole sizes, 0.6 and 0.8 cm, showed the highest efficiencies in controlling adult emergence in persimmon fruit and guava fruit.

  2. Parametric Probability Distribution Functions for Axon Diameters of Corpus Callosum

    Directory of Open Access Journals (Sweden)

    Farshid eSepehrband

    2016-05-01

    Full Text Available Axon diameter is an important neuroanatomical characteristic of the nervous system that alters in the course of neurological disorders such as multiple sclerosis. Axon diameters vary, even within a fiber bundle, and are not normally distributed. An accurate distribution function is therefore beneficial, either to describe axon diameters that are obtained from a direct measurement technique (e.g., microscopy, or to infer them indirectly (e.g., using diffusion-weighted MRI. The gamma distribution is a common choice for this purpose (particularly for the inferential approach because it resembles the distribution profile of measured axon diameters which has been consistently shown to be non-negative and right-skewed. In this study we compared a wide range of parametric probability distribution functions against empirical data obtained from electron microscopy images. We observed that the gamma distribution fails to accurately describe the main characteristics of the axon diameter distribution, such as location and scale of the mode and the profile of distribution tails. We also found that the generalized extreme value distribution consistently fitted the measured distribution better than other distribution functions. This suggests that there may be distinct subpopulations of axons in the corpus callosum, each with their own distribution profiles. In addition, we observed that several other distributions outperformed the gamma distribution, yet had the same number of unknown parameters; these were the inverse Gaussian, log normal, log logistic and Birnbaum-Saunders distributions.

  3. Effect of rootstock diameter on apple saplings growth

    Directory of Open Access Journals (Sweden)

    VAHID AVDIU

    2014-03-01

    Full Text Available This research paper presents the results of a field trial with managed nursery trees including two apple cultivars Golden Reinders and Gala Galaxy on the rootstocks M9 and MM 106. In April 2011, the saplings (bench grafted in March 2011 were planted in the distance 100 cm x 35 cm in randomized block design in threecombinations of rootstock diameters (5-7 mm, 7-9 mm, 9-11 mm with threereplications (in total 60 saplings for each apple cultivar-rootstock and combinations in Mirovica, Kosovo. The following parameters were examined: growth, rootstock diameter, scion diameter, and stocks growth dynamic. The experimental design was a ANOVAs one-way analysing two different factors cultivars, rootstocks types and treatments (three combinations of rootstocks diameter. Significant differences were found in scion thickness and sapling growth among the three different combinations of rootstock diameter, dimensions and cultivars. Insignificant were differences were found within factors as cultivar, rootstock and their combinations Key words: Amino acids, Moringa oleifera, poultry manure.

  4. Magnetoimpedance of Electroplated Wires with Large Core Diameters

    Institute of Scientific and Technical Information of China (English)

    C. Sirisathitkul; P. Jantaratana

    2009-01-01

    Monolayered Co and trilayered Co/Cu/Co were electroplated on 485 Μm-diameter Cu wires using the bath pH 2.5. These wires can be functioned as magnetic sensors owing to their magnetoimpedance (Ml) effect. By measuring at four different frequencies (100, 250, 500, and 1000 kHz) and Co thicknesses (2.5, 5.0, 10.0, and 25.0Μm), the Ml ratio of electroplated Co on Cu wires tended to increase with increasing Co thickness and frequency of the driving current. The Co/Cu/Co on Cu wires exhibited even higher Ml ratio. The magnetic layer also regulated the magnetic inductions and anisotropy regardless of the size of nonmagnetic core. Nevertheless, the diameter of the Cu core had a significant effect on the Ml ratio. By comparing with the 47.7 μm-diameter Ag cores electroplated by Co and Co/Cu/Co of the same thickness, the Cu cores with a larger diameter gave rise to a larger Ml ratio because their lower electrical resistance enhanced the crossing effect. Substantial Ml ratio was observed even in a low frequency regime because the skin effect occurred at a low frequency in the case of electroplated wires with large core diameters.

  5. Memory, emotion, and pupil diameter: Repetition of natural scenes.

    Science.gov (United States)

    Bradley, Margaret M; Lang, Peter J

    2015-09-01

    Recent studies have suggested that pupil diameter, like the "old-new" ERP, may be a measure of memory. Because the amplitude of the old-new ERP is enhanced for items encoded in the context of repetitions that are distributed (spaced), compared to massed (contiguous), we investigated whether pupil diameter is similarly sensitive to repetition. Emotional and neutral pictures of natural scenes were viewed once or repeated with massed (contiguous) or distributed (spaced) repetition during incidental free viewing and then tested on an explicit recognition test. Although an old-new difference in pupil diameter was found during successful recognition, pupil diameter was not enhanced for distributed, compared to massed, repetitions during either recognition or initial free viewing. Moreover, whereas a significant old-new difference was found for erotic scenes that had been seen only once during encoding, this difference was absent when erotic scenes were repeated. Taken together, the data suggest that pupil diameter is not a straightforward index of prior occurrence for natural scenes. © 2015 Society for Psychophysiological Research.

  6. Phagocytosis and hydrophobicity: a method of calculating contact angles based on the diameter of sessile drops.

    Science.gov (United States)

    Dahlgren, C; Sunqvist, T

    1981-01-01

    The correlation between the contact angle and degree of phagocytosis of different yeast particles has been investigated. To facilitate the estimation of the contact angle, we have tested the hypothesis that the shape of a small liquid drop put on a flat surface is that of a truncated sphere. By making this approximation it is possible to calculate the contact angle, i.e. the tangent to the drop in the 3-phase liquid/solid/air meeting point, by measuring the drop diameter. Known volumes of saline were put on different surfaces and the diameters of the drops were measured from above. Calculation of the contact angle with drops of different volumes, and comparison between expected and measured height of 10 microl drops, indicated that the assumption that the shape of a drop is that of a truncated sphere is valid. Monolayers of leukocytes was shown to give rise to a contact angle of 17.9 degrees. Particles with a lower contact angle than the phagocytic cells resisted phagocytosis, but opsonization of the particles with normal human serum rendered them susceptible to phagocytosis, conferring a higher contact angle than that of the phagocytic cells.

  7. Exploring the diameter and surface dependent conformational changes in carbon nanotube-protein corona and the related cytotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Xingchen; Lu, Dawei; Hao, Fang [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Liu, Rutao, E-mail: rutaoliu@sdu.edu.cn [Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, China–America CRC for Environment & Health, Jinan 250100 (China)

    2015-07-15

    Highlights: • CNT diameter and surface area govern the stability of adsorbed proteins. • More BSA was loaded and destabilized on smaller CNTs. • Protein corona reduces the cytotoxicity of CNTs - Abstract: In this work, we investigated and compared carbon nanotubes (CNTs) of different diameters regarding their interaction with bovine serum albumin (BSA) and their ability to alter protein structure. BSA was exposed to CNT solutions, and the effects were assessed by utilizing fluorescence spectroscopy, UV–vis absorption spectroscopy, circular dichroism (CD) spectroscopy, transmission electron microscopy (TEM), bichinchoninic acid (BCA) and zeta-potential measurement assays. We demonstrate that CNT diameter and surface area play key roles in influencing the stability of adsorbed proteins. Results showed that the secondary and tertiary structural stability of BSA decreased upon adsorption onto CNTs, with greater decrease on smaller-diametered nanotubes. Besides, more protein was loaded onto CNTs with small diameter, reducing the cytotoxicity. This study, therefore, provides fundamental information for the influence of CNT diameter and surface on protein behavior, which may be helpful to understand toxic effects of CNTs and prove beneficial for developing novel biomedical devices and safe use of nanomaterials.

  8. On sub-determinants and the diameter of polyhedra

    CERN Document Server

    Bonifas, Nicolas; Eisenbrand, Friedrich; Hähnle, Nicolai; Niemeier, Martin

    2011-01-01

    We derive a new upper bound on the diameter of a polyhedron P = {x \\in R^n : Ax <= b}, where A \\in Z^{m\\timesn}. The bound is polynomial in n and the largest absolute value of a sub-determinant of A, denoted by \\Delta. More precisely, we show that the diameter of P is bounded by O(\\Delta^2 n^4 log n\\Delta). If P is bounded, then we show that the diameter of P is at most O(\\Delta^2 n^3.5 log n\\Delta). For the special case in which A is a totally unimodular matrix, the bounds are O(n^4 log n) and O(n^3.5 log n) respectively. This improves over the previous best bound of O(m^16 n^3 (log mn)^3) due to Dyer and Frieze.

  9. Axon diameter mapping in crossing fibers with diffusion MRI

    DEFF Research Database (Denmark)

    Zhang, Hui; Dyrby, Tim B; Alexander, Daniel C

    2011-01-01

    tissue than measures derived from diffusion tensor imaging. Most existing techniques for axon diameter mapping assume a single axon orientation in the tissue model, which limits their application to only the most coherently oriented brain white matter, such as the corpus callosum, where the single...... orientation assumption is a reasonable one. However, fiber crossings and other complex configurations are widespread in the brain. In such areas, the existing techniques will fail to provide useful axon diameter indices for any of the individual fiber populations. We propose a novel crossing fiber tissue...... of the technique by establishing reasonable axon diameter indices in the crossing region at the interface of the cingulum and the corpus callosum....

  10. The angular diameter and distance of the Cepheid Zeta Geminorum

    CERN Document Server

    Kervella, P; Perrin, G; Schöller, M; Traub, W A; Lacasse, M D

    2001-01-01

    Cepheids are the primary distance indicators for extragalactic astronomy and therefore are of very high astrophysical interest. Unfortunately, they are rare stars, situated very far from Earth.Though they are supergiants, their typical angular diameter is only a few milliarcseconds, making them very challenging targets even for long-baseline interferometers. We report observations that were obtained in the K prime band (2-2.3 microns), on the Cepheid Zeta Geminorum with the FLUOR beam combiner, installed at the IOTA interferometer. The mean uniform disk angular diameter was measured to be 1.64 +0.14 -0.16 mas. Pulsational variations are not detected at a significant statistical level, but future observations with longer baselines should allow a much better estimation of their amplitude. The distance to Zeta Gem is evaluated using Baade-Wesselink diameter determinations, giving a distance of 502 +/- 88 pc.

  11. Improved Design Basis for Laterally Loaded Large Diameter Pile

    DEFF Research Database (Denmark)

    Leth, Caspar Thrane

    . The expected development of offshore wind farms is towards larger farms, larger turbines and larger water depths. Monopiles have been applied widely and it is of interest to investigate the possibilities to further optimize the design and in particular the modelling of the soil-structure interaction...... on the structure and the productivity of the turbine. Current design practice for monopiles are based on p-y curves developed for slender piles with a diameter of 0.6 m. The focus on the structure stiffness has entailed a significant research on the soil-structure interaction for large diameter monopiles...... in dry sand by use of centrifuge modelling and to compare the findings with the standard p-y curves. It has been chosen to apply piles with an embedment length of 6 to 10 times the diameter of the applied piles. The general static behaviour of monopiles in dry sand has based on centrifuge tests been...

  12. Directional Solidification and Convection in Small Diameter Crucibles

    Science.gov (United States)

    Chen, J.; Sung, P. K.; Tewari, S. N.; Poirier, D. R.; DeGroh, H. C., III

    2003-01-01

    Pb-2.2 wt% Sb alloy was directionally solidified in 1, 2, 3 and 7 mm diameter crucibles. Pb-Sb alloy presents a solutally unstable case. Under plane-front conditions, the resulting macrosegregation along the solidified length indicates that convection persists even in the 1 mm diameter crucible. Al-2 wt% Cu alloy was directionally solidified because this alloy was expected to be stable with respect to convection. Nevertheless, the resulting macrosegregation pattern and the microstructure in solidified examples indicated the presence of convection. Simulations performed for both alloys show that convection persists for crucibles as small as 0.6 mm of diameter. For the solutally stable alloy, Al-2 wt% Cu, the simulations indicate that the convection arises from a lateral temperature gradient.

  13. Improved Design Basis for Laterally Loaded Large Diameter Pile

    DEFF Research Database (Denmark)

    Leth, Caspar Thrane

    in dry sand by use of centrifuge modelling and to compare the findings with the standard p-y curves. It has been chosen to apply piles with an embedment length of 6 to 10 times the diameter of the applied piles. The general static behaviour of monopiles in dry sand has based on centrifuge tests been...... in sand by use of physical modelling and comparison of the findings with standard p-y curves. The present research is based on use of the centrifuge facilities at Danish Technical University (DTU), the sole geotechnical centrifuge in Scandinavia. It became evident in the initial phase of the research...... that the available centrifuge facilities at DTU was outdated and the focus was changed to establish up-to-date centrifuge facilities for medium to large diameter piles, and to initiate the research on the behaviour of large diameter piles in sand under static and cyclic loading. Key elements in the establishment...

  14. Application of direct tracking method for measuring electrospun nanofiber diameter

    Directory of Open Access Journals (Sweden)

    M. Ziabari

    2009-03-01

    Full Text Available In this paper, direct tracking method as an image analysis based technique for measuring electrospun nanofiber diameter has been presented and compared with distance transform method. Samples with known characteristics generated using a simulation scheme known as µ-randomness were employed to evaluate the accuracy of the method. Electrospun webs of polyvinyl alcohol (PVA were also used to verify the applicability of the method on real samples. Since direct tracking as well as distance transform require binary input images, micrographs of the electrospun webs obtained from Scanning Electron Microscopy (SEM were first converted to black and white using local thresholding. Direct tracking resulted in more accurate estimations of fiber diameter for simulated images as well as electrospun webs suggesting the usefulness of the method for electrospun nanofiber diameter measurement.

  15. NEOWISE Reactivation Mission Year Two: Asteroid Diameters and Albedos

    CERN Document Server

    Nugent, C R; Bauer, J; Cutri, R M; Kramer, E A; Grav, T; Masiero, J; Sonnett, S; Wright, E L

    2016-01-01

    The Near-Earth Object Wide-Field Infrared Survey Explorer (NEOWISE) mission continues to detect, track, and characterize minor planets. We present diameters and albedos calculated from observations taken during the second year since the spacecraft was reactivated in late 2013. These include 207 near-Earth asteroids and 8,885 other asteroids. $84\\%$ of the near-Earth asteroids did not have previously measured diameters and albedos by the NEOWISE mission. Comparison of sizes and albedos calculated from NEOWISE measurements with those measured by occultations, spacecraft, and radar-derived shapes shows accuracy consistent with previous NEOWISE publications. Diameters and albedos fall within $ \\pm \\sim20\\%$ and $\\pm\\sim40\\%$, 1-sigma, respectively, of those measured by these alternate techniques. NEOWISE continues to preferentially discover near-Earth objects which are large ($>100$ m), and have low albedos.

  16. Decreased group velocity in compositionally graded films.

    Science.gov (United States)

    Gao, Lei

    2006-03-01

    A theoretical formalism is presented that describes the group velocity of electromagnetic signals in compositionally graded films. The theory is first based on effective medium approximation or the Maxwell-Garnett approximation to obtain the equivalent dielectric function in a z slice. Then the effective dielectric tensor of the graded film is directly determined, and the group velocities for ordinary and extraordinary waves in the film are derived. It is found that the group velocity is sensitively dependent on the graded profile. For a power-law graded profile f(x)=ax(m), increasing m results in the decreased extraordinary group velocity. Such a decreased tendency becomes significant when the incident angle increases. Therefore the group velocity in compositionally graded films can be effectively decreased by our suitable adjustment of the total volume fraction, the graded profile, and the incident angle. As a result, the compositionally graded films may serve as candidate material for realizing small group velocity.

  17. Pupil diameter tracks changes in control state predicted by the adaptive gain theory of locus coeruleus function.

    Science.gov (United States)

    Gilzenrat, Mark S; Nieuwenhuis, Sander; Jepma, Marieke; Cohen, Jonathan D

    2010-05-01

    An important dimension of cognitive control is the adaptive regulation of the balance between exploitation (pursuing known sources of reward) and exploration (seeking new ones) in response to changes in task utility. Recent studies have suggested that the locus coeruleus-norepinephrine system may play an important role in this function and that pupil diameter can be used to index locus coeruleus activity. On the basis of this, we reasoned that pupil diameter may correlate closely with control state and associated changes in behavior. Specifically, we predicted that increases in baseline pupil diameter would be associated with decreases in task utility and disengagement from the task (exploration), whereas reduced baseline diameter (but increases in task-evoked dilations) would be associated with task engagement (exploitation). Findings in three experiments were consistent with these predictions, suggesting that pupillometry may be useful as an index of both control state and, indirectly, locus coeruleus function.

  18. Optical coating uniformity of 200mm (8") diameter precut wafers

    Science.gov (United States)

    Burt, Travis C.; Fisher, Mark; Brown, Dean; Troiani, David

    2017-02-01

    Automated spectroscopic profiling (mapping) of a 200 mm diameter near infrared high reflector (centered at 1064 nm) are presented. Spatial resolution at 5 mm or less was achieved using a 5 mm × 1.5 mm monochromatic beam. Reflection changes of 1.0% across the wafer diameter were observed under s-polarized and p- polarized conditions. Redundancy was established for each chord by re-measuring the center of the wafer and reproducibility of approximately platform for angles of incidence in the range 5°stream processing.

  19. On the diameter of the Kronecker product graph

    CERN Document Server

    Hu, Fu-Tao

    2012-01-01

    Let $G_1$ and $G_2$ be two undirected nontrivial graphs. The Kronecker product of $G_1$ and $G_2$ denoted by $G_1\\otimes G_2$ with vertex set $V(G_1)\\times V(G_2)$, two vertices $x_1x_2$ and $y_1y_2$ are adjacent if and only if $(x_1,y_1)\\in E(G_1)$ and $(x_2,y_2)\\in E(G_2)$. This paper presents a formula for computing the diameter of $G_1\\otimes G_2$ by means of the diameters and primitive exponents of factor graphs.

  20. NEOWISE REACTIVATION MISSION YEAR ONE: PRELIMINARY ASTEROID DIAMETERS AND ALBEDOS

    Energy Technology Data Exchange (ETDEWEB)

    Nugent, C. R.; Cutri, R. M. [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States); Mainzer, A.; Masiero, J.; Bauer, J.; Kramer, E.; Sonnett, S.; Stevenson, R. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Grav, T. [Planetary Science Institute, Tucson, AZ (United States); Wright, E. L., E-mail: cnugent@ipac.caltech.edu [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States)

    2015-12-01

    We present preliminary diameters and albedos for 7956 asteroids detected in the first year of the NEOWISE Reactivation mission. Of those, 201 are near-Earth asteroids and 7755 are Main Belt or Mars-crossing asteroids. 17% of these objects have not been previously characterized using the Near-Earth Object Wide-field Infrared Survey Explorer, or “NEOWISE” thermal measurements. Diameters are determined to an accuracy of ∼20% or better. If good-quality H magnitudes are available, albedos can be determined to within ∼40% or better.

  1. The effect of the impactor diameter and temperature on low velocity impact behavior of CFRP laminates

    Science.gov (United States)

    Evci, C.; Uyandıran, I.

    2017-02-01

    Impact damage is one of the major concerns that should be taken into account with the new aircraft and spacecraft structures which employ ever-growing use of composite materials. Considering the thermal loads encountered at different altitudes, both low and high temperatures can affect the properties and impact behavior of composite materials. This study aims to investigate the effect of temperature and impactor diameter on the impact behavior and damage development in balanced and symmetrical CFRP laminates which were manufactured by employing vacuum bagging process with autoclave cure. Instrumented drop-weight impact testing system is used to perform the low velocity impact tests in a range of temperatures ranged from 60 down to -50 °C. Impact tests for each temperature level were conducted using three different hemispherical impactor diameters varying from 10 to 20 mm. Energy profile method is employed to determine the impact threshold energies for damage evolution. The level of impact damage is determined from the dent depth on the impacted face and delamination damage detected using ultrasonic C-Scan technique. Test results reveal that the threshold of penetration energy, main failure force and delamination area increase with impactor diameter at all temperature levels. No clear influence of temperature on the critical force thresholds could be derived. However, penetration threshold energy decreased as the temperature was lowered. Drop in the penetration threshold was more obvious with quite low temperatures. Delamination damage area increased while the temperature decreased from +60 °C to -50 °C.

  2. Ageing effects on the diameter, nanomechanical properties and tactile perception of human hair.

    Science.gov (United States)

    Tang, W; Zhang, S G; Zhang, J K; Chen, S; Zhu, H; Ge, S R

    2016-04-01

    The typical changes to hair associated with ageing are greying, thinning, dryness and brittleness. Research on the influence of ageing on hair properties will enable a detailed understanding of the natural ageing process. The studies were carried out using an SEM (scanning electron microscope), a TriboIndenter and an artificial finger. Three characteristic features of tactile perception that could reflect the perceptual dimensions of the fineness, roughness and slipperiness of hair were extracted. The influences of ageing on the diameter, surface topography, nanomechanical properties and tactile perception of hair were determined. In the three age group hair samples, the children's group hair samples have the smallest diameter. The hair cuticles in the children and young adult groups were relatively complete and less damaged than in the elderly group. The hardness and elastic modulus of the young adult group's hair samples were higher than those in the elderly and children's groups. For all groups, loss modulus E" was smaller than storage modulus E'. Vertical deviations (R) and coefficient of friction (μ) increased, and spectral centroid (SC) decreased, with the increase in age. Ageing decreased the tactile perception of hair. Ageing influences the diameter, surface topography, hardness, loss modulus, storage modulus and tactile perception of human hair. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  3. Renormalized Volume

    Science.gov (United States)

    Gover, A. Rod; Waldron, Andrew

    2017-09-01

    We develop a universal distributional calculus for regulated volumes of metrics that are suitably singular along hypersurfaces. When the hypersurface is a conformal infinity we give simple integrated distribution expressions for the divergences and anomaly of the regulated volume functional valid for any choice of regulator. For closed hypersurfaces or conformally compact geometries, methods from a previously developed boundary calculus for conformally compact manifolds can be applied to give explicit holographic formulæ for the divergences and anomaly expressed as hypersurface integrals over local quantities (the method also extends to non-closed hypersurfaces). The resulting anomaly does not depend on any particular choice of regulator, while the regulator dependence of the divergences is precisely captured by these formulæ. Conformal hypersurface invariants can be studied by demanding that the singular metric obey, smoothly and formally to a suitable order, a Yamabe type problem with boundary data along the conformal infinity. We prove that the volume anomaly for these singular Yamabe solutions is a conformally invariant integral of a local Q-curvature that generalizes the Branson Q-curvature by including data of the embedding. In each dimension this canonically defines a higher dimensional generalization of the Willmore energy/rigid string action. Recently, Graham proved that the first variation of the volume anomaly recovers the density obstructing smooth solutions to this singular Yamabe problem; we give a new proof of this result employing our boundary calculus. Physical applications of our results include studies of quantum corrections to entanglement entropies.

  4. Collagen fibril diameter distribution does not reflect changes in the mechanical properties of in vitro stress-deprived tendons.

    Science.gov (United States)

    Lavagnino, Michael; Arnoczky, S P Steven P; Frank, Katherine; Tian, Tao

    2005-01-01

    The purpose of this study was to determine if an association exists between the tensile properties and the collagen fibril diameter distribution in in vitro stress-deprived rat tail tendons. Rat tail tendons were paired into two groups of 21 day stress-deprived and 0 time controls and compared using transmission electron microscopy (n = 6) to measure collagen fibril diameter distribution and density, and mechanical testing (n =6) to determine ultimate stress and tensile modulus. There was a statistically significant decrease in both ultimate tensile strength (control: 17.95+/-3.99 MPa, stress-deprived: 6.79+/-3.91 MPa) and tensile modulus (control: 312.8+/-89.5 MPa, stress-deprived: 176.0+/-52.7 MPa) in the in vitro stress-deprived tendons compared to controls. However, there was no significant difference between control and stress-deprived tendons in the number of fibrils per tendon counted, mean fibril diameter, mean fibril density, or fibril size distribution. The results of this study demonstrate that the decrease in mechanical properties observed in in vitro stress-deprived rat tail tendons is not correlated with the collagen fibril diameter distribution and, therefore, the collagen fibril diameter distribution does not, by itself, dictate the decrease in mechanical properties observed in in vitro stress-deprived rat tail tendons.

  5. Use of the method of Boolean models to study different methods of drilling wells of large diameter

    Energy Technology Data Exchange (ETDEWEB)

    Selivanov, A.N.; Ryabinin, A.I.

    1981-01-01

    A description is made of the method of statistical modeling using the method of Boolean models as an example of processing and analyzing the results of drilling wells of large diameter by different methods. It is indicated that this method as compared to traditional methods of multiple-factor analysis with comparatively small volume of experimental data makes it possible to obtain a complete qualitative and quantitative characterization of the studied phenomenon.

  6. Accuracy and Sources of Error for an Angle Independent Volume Flow Estimator

    DEFF Research Database (Denmark)

    Jensen, Jonas; Olesen, Jacob Bjerring; Hansen, Peter Møller

    2014-01-01

    This paper investigates sources of error for a vector velocity volume flow estimator. Quantification of the estima tor’s accuracy is performed theoretically and investigated in vivo . Womersley’s model for pulsatile flow is used to simulate velo city profiles and calculate volume flow errors in c...... % underestimated volume flow according to the simulation. Volume flow estimates were corrected for the beam being off- axis, but was not able to significantly decrease the error rel ative to measurements with the reference method.......This paper investigates sources of error for a vector velocity volume flow estimator. Quantification of the estima tor’s accuracy is performed theoretically and investigated in vivo . Womersley’s model for pulsatile flow is used to simulate velo city profiles and calculate volume flow errors....... A BK Medical UltraView 800 ultrasound scanner with a 9 MHz linear array transducer is used to obtain Vector Flow Imaging sequences of a superficial part of the fistulas. Cross-sectional diameters of each fistu la are measured on B-mode images by rotating the scan plane 90 degrees. The major axis...

  7. Ion Channels Involved in Cell Volume Regulation

    DEFF Research Database (Denmark)

    Hoffmann, Else Kay

    2011-01-01

    This mini review outlines studies of cell volume regulation in two closely related mammalian cell lines: nonadherent Ehrlich ascites tumour cells (EATC) and adherent Ehrlich Lettre ascites (ELA) cells. Focus is on the regulatory volume decrease (RVD) that occurs after cell swelling, the volume...

  8. Small-diameter prosthetic H-graft portacaval shunts in the treatment of portal hypertension

    Institute of Scientific and Technical Information of China (English)

    胡何节; 许戈良; 李建生; 杨树高; 柴仲培; 徐荣楠

    2004-01-01

    Background Portasystemic shunts, especially total shunts, are effective tools for reducing portal pressure and controlling variceal bleeding but lead to high risk of encephalopathy and accelerating liver ailure. The purpose of this study is to evaluate the clinical effects of small-diameter expanded polytetrafluoroethylene (ePTFE) H-graft portacaval shunts in the treatment of portal hypertension. Methods Thirty-one patients with portal hypertension were treated with ePTFE small-diameter H-graft portacaval shunts from December 1995 to April 2002. Twenty-one had externally ringed grafts and 10 had non-ringed grafts; 20 had 10 mm diameter grafts and 11 had 8 mm grafts. The left gastric artery and coronary vein were ligated in 22 patients. Additionally, 6 patients underwent pericardial devascularization, and splenectomies were performed on 30 patients. Results An average decrease of free portal pressure (FPP) from (32.13 ~4.86) cmH2O before shunting to (12.55±5. 57) cmH2O after shunting was observed. Portal blood flow was reduced by 1/3 compared with the levels measured before shunting. Twenty-eight patients survived after the operation, and no upper gastrointestinal rebleeding occurred in the follow-up period (40.2 months on average). We lost contact with one patient. Color Doppler ultrasonography and/or portography revealed the shunts to be patent in 28 cases and occluded in 2 (6.4% ) cases. Encephalopathy developed in 4 patients (12.9%). Conclusion Small-diameter ePTFE H-graft portacaval shunts can effectively reduce portal pressure. Moreover, the majority of the hepatopetal flow from the portal vein can be adequately maintained. The reinforced shunts may achieve a higher rate of patency. Morbidity from encephalopathy was less frequent than in pateints receiving total shunts. Small-diameter H-graft portacaval shunts are also effective in preventing recurrent variceal bleeding.

  9. Evaluation function of drinking ease from aluminum beverage bottles relative to optimum bottle opening diameter and beverage type.

    Science.gov (United States)

    Chihara, Takanori; Yamazaki, Koetsu

    2012-01-01

    In recent years, aluminum beverage bottles having screw tops with opening diameters of 28 and 38 mm have been launched in the Japanese market in keeping with the modern-day drinking habits of consumers. Although Japanese consumers are familiar with such bottles, a majority of them feel that the 28 mm opening is too small and the 38 mm opening is too large. Therefore, we felt the need to develop a method for evaluating consumer feelings when they drink a beverage directly from the bottle opening. For this purpose, we propose an evaluation function of drinking ease that calculates the optimum opening diameter of the bottle. From results of our previous study, we know that there exists an ideal volume of beverage flowing into the mouth, at which consumers feel most comfortable while drinking directly from bottles. Therefore, we define the evaluation function of drinking ease in terms of the difference between the actual volume of fluid in the mouth and the expected ideal volume. If this difference is small, consumers probably feel comfortable while drinking the beverage. We consider a design variable, i.e., the opening diameter, and two state variables, i.e., the volume of beverage remaining in the bottle and the height of consumers, and construct the response surface of the evaluation function by using radial basis function networks. In addition, for investigating the influence of beverage type on the evaluation function, we select green tea and a carbonated beverage (Coke) as test beverages. Results of optimization of the proposed function show that when the opening diameters are 35.4 mm and 34.4 mm in the case of green tea and Coke, respectively, the actual volume of fluid in the mouth is closest to the ideal volume and the participants feel most comfortable. These results are in agreement with results of our previous study that an opening diameter of 33 mm is optimum for young Japanese adults. Thus, we confirm that the proposed function is accurate; it can be used

  10. Temperature-dependent gas transport and its correlation with kinetic diameter in polymer nanocomposite membrane

    Indian Academy of Sciences (India)

    N K ACHARYA

    2017-06-01

    Activation energies for permeation of polymer nanocomposite membrane have not been reported so far. A tradeoff relation between permeability and selectivity shows that as permeability increases, the selectivity decreases. Attempts have been made to see this trade-off relation at relatively higher temperature. It is found that selectivity decreases drasticallywith increasing temperature.Apolymer–matrix compositewas prepared by adding silica nanoparticles using casting method. Pure gas permeability was measured using a constant volume–variable pressure method at different temperature ranges from 35 to 70$^{\\circ}$C. The Van’t Hoff relation was used to estimate the activation energy for permeation. It is found to decrease as compared with virgin polycarbonate and it increases with kinetic diameter. For the first time, the permeability and selectivity for nanocomposite membrane are reported as a function of temperature. Activation energies for different gases have beencalculated for nanocomposite membrane and comparedwith that of virgin polymer membrane. Decrease in activation energies for permeation ($E_p$) with increasing kinetic diameter has been observed for both the membranes. Selectivity reduces with temperature for both the membranes.Mechanical and thermal properties of nanocomposite membrane have been investigatedusing a dynamic mechanical analyser and differential scanning calorimetry, respectively. Scanning electron microscopy has been used to study surface morphology. The results show modification in physical properties due to incorporation of silica nanoparticles.

  11. Effect of high-pressure homogenization preparation on mean globule size and large-diameter tail of oil-in-water injectable emulsions

    Directory of Open Access Journals (Sweden)

    Jie Peng

    2015-12-01

    Full Text Available The effect of different high pressure homogenization energy input parameters on mean diameter droplet size (MDS and droplets with > 5 μm of lipid injectable emulsions were evaluated. All emulsions were prepared at different water bath temperatures or at different rotation speeds and rotor-stator system times, and using different homogenization pressures and numbers of high-pressure system recirculations. The MDS and polydispersity index (PI value of the emulsions were determined using the dynamic light scattering (DLS method, and large-diameter tail assessments were performed using the light-obscuration/single particle optical sensing (LO/SPOS method. Using 1000 bar homogenization pressure and seven recirculations, the energy input parameters related to the rotor-stator system will not have an effect on the final particle size results. When rotor-stator system energy input parameters are fixed, homogenization pressure and recirculation will affect mean particle size and large diameter droplet. Particle size will decrease with increasing homogenization pressure from 400 bar to 1300 bar when homogenization recirculation is fixed; when the homogenization pressure is fixed at 1000 bar, the particle size of both MDS and percent of fat droplets exceeding 5 μm (PFAT5 will decrease with increasing homogenization recirculations, MDS dropped to 173 nm after five cycles and maintained this level, volume-weighted PFAT5 will drop to 0.038% after three cycles, so the “plateau” of MDS will come up later than that of PFAT5, and the optimal particle size is produced when both of them remained at plateau. Excess homogenization recirculation such as nine times under the 1000 bar may lead to PFAT5 increase to 0.060% rather than a decrease; therefore, the high-pressure homogenization procedure is the key factor affecting the particle size distribution of emulsions. Varying storage conditions (4–25°C also influenced particle size, especially the PFAT

  12. Scalable synthesis and characterization of cobalt sodium tartrate nanowires with adjustable diameters

    Science.gov (United States)

    Chen, Lan; Tang, Shaochun; Vongehr, Sascha; Hu, Kun; Meng, Xiangkang

    2011-11-01

    Cobalt sodium tartrate nanowires are synthesized by a simple hydrothermal method using ethanol-water mixed solvents. The smooth wires are on average 30 μm long. Their diameters are narrowly size distributed with a controllable average in the range from 80 to 250 nm. Interestingly, after the initial two hours, the diameter decreases with further reaction time. The tartrate anions act as coordination ligands with all six oxygen atoms participating in the coordination. The Co 2+ and Na + ions chelate with the O atoms from the carboxylate and hydroxyl groups in the tartrate ligands. The ethanol participates in the formation of pi bonds. The cobalt is divalent while the sodium is monovalent in their tartrates. The respective crystal structures of these metal tartrates are incompatible, and the wires are therefore amorphous. The influence of the reaction time, sodium tartrate concentration, pH value, and the ethanol water ratio are studied in detail.

  13. Experimental study on the near wake behind two side-by-side cylinders of unequal diameters

    Science.gov (United States)

    Gao, Yangyang; Yu, Dingyong; Tan, Soonkeat; Wang, Xikun; Hao, Zhiyong

    2010-10-01

    The wake structure behind two side-by-side circular cylinders with unequal diameter was investigated using the particle image velocimetry (PIV) technique. This investigation focused on the asymmetrical flow within the subcritical Reynolds number regime. A comparison between the time-averaged mean flow field of one cylinder and that of two side-by-side cylinders of unequal diameter was made for elucidating the mean flow characteristics attributable to the latter. The distribution of mean velocity behind two side-by-side unequal cylinders was distinctly different from that behind one cylinder, and an asymmetric combination was observed behind the two cylinders. The present paper also presents the authors' interpretation of the generation mechanism of gap flow deflection based on the instantaneous vorticity contours and velocity distribution. The effect of Reynolds number on flow structure was studied by analyzing the mean velocity distribution and time-averaged wake structures. The results showed that vortex formation length decreases with Reynolds number.

  14. Numerical investigation on thermal striping conditions for a tee junction of LMFBR coolant pipes. 3. Investigation on diameter ratio between the coolant pipes

    Energy Technology Data Exchange (ETDEWEB)

    Muramatsu, Toshiharu [Japan Nuclear Cycle Development Inst., Oarai, Ibaraki (Japan). Oarai Engineering Center

    1999-04-01

    This report presents numerical results on thermal striping characteristics at a tee junction of LMFBR coolant pipe, carried out using a direct numerical simulation code DINUS-3. In the numerical investigations, it was considered a tee junction system consisted of a main pipe (1.33 cm{sup I.D.}) with a 90deg elbow and a branch pipe having various inner diameters, and five diameter ratio conditions between both the pipes, i.e., (D{sub main}/D{sub branch}) = 1.0, 2.0, 3.0, 5.0 and 10.0. From the numerical investigations, the following characteristics were obtained: (1) Maximum sodium temperature fluctuation amplitude in the downstream region of the tee junction were decreased with increasing of the diameter ratio (decreasing of the branch pipe diameter). One of the main reasons for this behavior was considered to be that the affects of the branch pipe jet for the main pipe flows was decreased with decreasing of the branch pipe diameter. (2) Auto-power spectral density levels were decreased by the increasing of the diameter ratio. It was indicated that coolant mixing characteristics in the downstream region were controlled by locally random turbulence processes. (3) To suppress sodium temperature fluctuations in the downstream region, it is a suitable combination for larger velocity ratio and larger diameter ratio. (author)

  15. Uncertainty budget for optical coordinate measurements of circle diameter

    DEFF Research Database (Denmark)

    Morace, Renate Erica; Hansen, Hans Nørgaard; De Chiffre, Leonardo

    2004-01-01

    An uncertainty analysis for circle diameter measurements using a coordinate measuring machine (CMM) equipped with an optical probe is presented in this paper. A mathematical model for data evaluation and uncertainty assessment was formulated in accordance with Guide to the Expression of Uncertain...

  16. Experimental study on strain sensing by small-diameter FBG

    Science.gov (United States)

    Liu, Rong-mei; Li, Qiufeng; Zhu, Lujia; Liang, Dakai

    2016-11-01

    Fiber Bragg grating (FBG) sensors were attractive in various fields for structural health monitoring. Because of their accurate performance and real time response, embedded FBG sensors are promising for strain monitoring in composite materials. As an optical fiber sensor was embedded inside a composite, interface would form around the embedded optical fiber and the host polymer composite. In order to study the influence of the embedded optical fiber to the mechanical character, finite elemental analysis was applied to study the stress distribution inside the composite. Keeping the resin rich area the same size, laminates with optical fibers in different diameters, which were 250 and 125 micrometers, were analyzed. The simulation results represent that stress singularity would occur around the embedded optical fiber. The singularity value for the laminate with optical fiber at 250 micrometer was higher than that with optical fiber at 125 micrometer. Micro- cracks would arise at the stress singularity point. Therefore, the optical fiber in smaller diameter was preferred since the mechanical strength could be higher. Four points bending test was carried out on a steel beam with a small-diameter FBG on the bottom surface. Besides, a strain gauge was stuck on bottom to validate the monitoring results by FBG sensor. The tested results indicated that the strain monitoring results by the small-diameter FBG sensor almost identical with the theoretical ones and what recorded by strain gauge. The maximum testing error for the designed FBG is less than 2% compared with the theoretical one.

  17. Predicted and observed finger diameters in field soils

    NARCIS (Netherlands)

    Ritsema, C.J.; Steenhuis, T.S.; Parlange, J.Y.; Dekker, L.W.

    1996-01-01

    Wetting front instability resulting in fingered flow has been found in both wettable and non-wettable soils. Laboratory research has resulted in a number of expressions for finger diameter. The applicability of one of these equations was tested for three soils where detailed soil moisture contents w

  18. Rowlinson’s concept of an effective hard sphere diameter

    Science.gov (United States)

    Henderson, Douglas

    2010-01-01

    Attention is drawn to John Rowlinson’s idea that the repulsive portion of the intermolecular interaction may be replaced by a temperature-dependent hard sphere diameter. It is this approximation that made the development of perturbation theory possible for realistic fluids whose intermolecular interactions have a steep, but finite, repulsion at short separations. PMID:20953320

  19. Rowlinson's concept of an effective hard sphere diameter.

    Science.gov (United States)

    Henderson, Douglas

    2010-01-01

    Attention is drawn to John Rowlinson's idea that the repulsive portion of the intermolecular interaction may be replaced by a temperature-dependent hard sphere diameter. It is this approximation that made the development of perturbation theory possible for realistic fluids whose intermolecular interactions have a steep, but finite, repulsion at short separations.

  20. FACES WITH LARGE DIAMETER ON THE SYMMETRICAL TRAVELING SALESMAN POLYTOPE

    NARCIS (Netherlands)

    SIERKSMA, G; TIJSSEN, GA

    1992-01-01

    This paper deals with the symmetric traveling salesman polytope and contains three main theorems. The first one gives a new characterization of (non)adjacency. Based on this characterization a new upper bound for the diameter of the symmetric traveling salesman polytope (conjectured to be 2 by M. Gr

  1. Definition of Beam Diameter for Electron Beam Welding

    Energy Technology Data Exchange (ETDEWEB)

    Burgardt, Paul [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pierce, Stanley W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dvornak, Matthew John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-03-11

    It is useful to characterize the dimensions of the electron beam during process development for electron beam welding applications. Analysis of the behavior of electron beam welds is simplest when a single number can be assigned to the beam properties that describes the size of the beam spot; this value we generically call the “beam diameter”. This approach has worked well for most applications and electron beam welding machines with the weld dimensions (width and depth) correlating well with the beam diameter. However, in recent weld development for a refractory alloy, Ta-10W, welded with a low voltage electron beam machine (LVEB), it was found that the weld dimensions (weld penetration and weld width) did not correlate well with the beam diameter and especially with the experimentally determined sharp focus point. These data suggest that the presently used definition of beam diameter may not be optimal for all applications. The possible reasons for this discrepancy and a suggested possible alternative diameter definition is the subject of this paper.

  2. Calibration of Laser Beam Direction for Inner Diameter Measuring Device

    Directory of Open Access Journals (Sweden)

    Tongyu Yang

    2017-02-01

    Full Text Available The laser triangulation method is one of the most advanced methods for large inner diameter measurement. Our research group proposed a kind of inner diameter measuring device that is principally composed of three laser displacement sensors known to be fixed in the same plane measurement position. It is necessary to calibrate the direction of the laser beams that are emitted by laser displacement sensors because they do not meet the theoretical model accurately. For the purpose of calibrating the direction of laser beams, a calibration method and mathematical model were proposed. The inner diameter measuring device is equipped with the spindle of the machine tool. The laser beams rotate and translate in the plane and constitute the rotary rays which are driven to scan the inner surface of the ring gauge. The direction calibration of the laser beams can be completed by the sensors’ distance information and corresponding data processing method. The corresponding error sources are analyzed and the validity of the method is verified. After the calibration, the measurement error of the inner diameter measuring device reduced from ± 25 μ m to ± 15 μ m and the relative error was not more than 0.011%.

  3. Diameter-dependent conductance of InAs nanowires

    NARCIS (Netherlands)

    Scheffler, M.; Nadj-Perge, S.; Kouwenhoven, L.P.; Borgström, M.T.; Bakkers, E.P.A.M.

    2009-01-01

    Electrical conductance through InAs nanowires is relevant for electronic applications as well as for fundamental quantum experiments. Here, we employ nominally undoped, slightly tapered InAs nanowires to study the diameter dependence of their conductance. By contacting multiple sections of each wire

  4. Asteroid magnitudes, UBV colors, and IRAS albedos and diameters

    Science.gov (United States)

    Tedesco, Edward F.

    1989-01-01

    This paper lists absolute magnitudes and slope parameters for known asteroids numbered through 3318. The values presented are those used in reducing asteroid IR flux data obtained with the IRAS. U-B colors are given for 938 asteroids, and B-V colors are given for 945 asteroids. The IRAS albedos and diameters are tabulated for 1790 asteroids.

  5. A small-diameter NMR logging tool for groundwater investigations.

    Science.gov (United States)

    Walsh, David; Turner, Peter; Grunewald, Elliot; Zhang, Hong; Butler, James J; Reboulet, Ed; Knobbe, Steve; Christy, Tom; Lane, John W; Johnson, Carole D; Munday, Tim; Fitzpatrick, Andrew

    2013-01-01

    A small-diameter nuclear magnetic resonance (NMR) logging tool has been developed and field tested at various sites in the United States and Australia. A novel design approach has produced relatively inexpensive, small-diameter probes that can be run in open or PVC-cased boreholes as small as 2 inches in diameter. The complete system, including surface electronics and various downhole probes, has been successfully tested in small-diameter monitoring wells in a range of hydrogeological settings. A variant of the probe that can be deployed by a direct-push machine has also been developed and tested in the field. The new NMR logging tool provides reliable, direct, and high-resolution information that is of importance for groundwater studies. Specifically, the technology provides direct measurement of total water content (total porosity in the saturated zone or moisture content in the unsaturated zone), and estimates of relative pore-size distribution (bound vs. mobile water content) and hydraulic conductivity. The NMR measurements show good agreement with ancillary data from lithologic logs, geophysical logs, and hydrogeologic measurements, and provide valuable information for groundwater investigations.

  6. Estimating Tree Height-Diameter Models with the Bayesian Method

    Directory of Open Access Journals (Sweden)

    Xiongqing Zhang

    2014-01-01

    Full Text Available Six candidate height-diameter models were used to analyze the height-diameter relationships. The common methods for estimating the height-diameter models have taken the classical (frequentist approach based on the frequency interpretation of probability, for example, the nonlinear least squares method (NLS and the maximum likelihood method (ML. The Bayesian method has an exclusive advantage compared with classical method that the parameters to be estimated are regarded as random variables. In this study, the classical and Bayesian methods were used to estimate six height-diameter models, respectively. Both the classical method and Bayesian method showed that the Weibull model was the “best” model using data1. In addition, based on the Weibull model, data2 was used for comparing Bayesian method with informative priors with uninformative priors and classical method. The results showed that the improvement in prediction accuracy with Bayesian method led to narrower confidence bands of predicted value in comparison to that for the classical method, and the credible bands of parameters with informative priors were also narrower than uninformative priors and classical method. The estimated posterior distributions for parameters can be set as new priors in estimating the parameters using data2.

  7. Real-time precision measuring device of tree diameter growth

    Science.gov (United States)

    Guo, Mingming; Chen, Aijun; Li, Dongsheng; Liu, Nan; Yao, Jingyuan

    2016-01-01

    DBH(diameter at breast height) is an important factor to reflect of the quality of plant growth, also an important parameter indispensable in forest resources inventory and forest carbon sink, the accurate measurement of DBH or not is directly related to the research of forest resources inventory and forest carbon sink. In this paper, the principle and the mathematical model of DBH measurement device were introduced, the fixture measuring device and the hardware circuit for this tree diameter were designed, the measurement software programs were compiled, and the precision measuring device of tree diameter growth was developed. Some experiments with Australia fir were conducted. Based on experiment data, the correlations among the DBH variation of Australian fir, the environment temperature, air humility and PAR(photosynthetically active radiation) were obtained. The effects of environmental parameters (environment temperature, air humility and PAR) on tree diameter were analyzed. Experimental results show that there is a positive correlation between DBH variation of Australian fir and environment temperature, a negative correlation between DBH variation of Australian fir and air humility , so is PAR.

  8. The Angular Diameter and Fundamental Parameters of Sirius A

    CERN Document Server

    Davis, J; North, J R; Robertson, J G; Tango, W J; Tuthill, P G

    2010-01-01

    The Sydney University Stellar Interferometer (SUSI) has been used to make a new determination of the angular diameter of Sirius A. The observations were made at an effective wavelength of 694.1 nm and the new value for the limb-darkened angular diameter is 6.048 +/- 0.040mas (+/-0.66%). This new result is compared with previous measurements and is found to be in excellent agreement with a conventionally calibrated measurement made with the European Southern Observatory's Very Large Telescope Interferometer (VLTI) at 2.176 microns (but not with a second globally calibrated VLTI measurement). A weighted mean of the SUSI and first VLTI results gives the limb-darkened angular diameter of Sirius A as 6.041 +/- 0.017mas (+/-0.28%). Combination with the Hipparcos parallax gives the radius equal to 1.713 +/- 0.009R_sun. The bolometric flux has been determined from published photometry and spectrophotometry and, combined with the angular diameter, yields the emergent flux at the stellar surface equal to (5.32+/- 0.14)...

  9. Observations on placentome diameters in gestating West African ...

    African Journals Online (AJOL)

    ADEYEYE

    2015-09-09

    Sep 9, 2015 ... Department of Veterinary Surgery and Reproduction, University of Ibadan, Ibadan, Nigeria ... This study investigated the effect of experimental Trypanosoma brucei infection on the placentome diameter (PD) ... symptoms/clinical signs in female mammalian ..... Global Library Women's Medicine, London,.

  10. Small-diameter trees used for chemithermomechanical pulps.

    Science.gov (United States)

    Gary C. Myers; R. James. Barbour; Said M. Abubakr

    1999-01-01

    During the course of restoring and maintaining forest ecosystem health and function in the western interior of the United States, many small-diameter stems are removed from densely stocked stands. In general, these materials are considered nonusable or underutilized. Information on the properties of these resources is needed to help managers understand when timber...

  11. Processing of fine-diameter continuous mullite fibers

    Energy Technology Data Exchange (ETDEWEB)

    Al-Assafi, S.; Cruse, T.; Simmons, J.H. [Univ. of Florida, Gainesville, FL (United States)] [and others

    1994-12-31

    Fine-diameter, continuous mullite fibers were fabricated by sol-gel processing using two different chelating agents on weight loss behavior, mullite formation, and sintered fiber microstructure were examined. The molar ratio, R, of chelating agent to alumina precursor in the sol was varied in order to optimize continuous spinning conditions. The importance of aging conditions on the sintered fiber density was demonstrated.

  12. Bipartite Diametrical Graphs of Diameter 4 and Extreme Orders

    Directory of Open Access Journals (Sweden)

    Salah Al-Addasi

    2008-01-01

    in which this upper bound is attained, this graph can be viewed as a generalization of the Rhombic Dodecahedron. Then we show that for any ≥2, the graph (2,2 is the unique (up to isomorphism bipartite diametrical graph of diameter 4 and partite sets of cardinalities 2 and 2, and hence in particular, for =3, the graph (6,8 which is just the Rhombic Dodecahedron is the unique (up to isomorphism bipartite diametrical graph of such a diameter and cardinalities of partite sets. Thus we complete a characterization of -graphs of diameter 4 and cardinality of the smaller partite set not exceeding 6. We prove that the neighborhoods of vertices of the larger partite set of (2,2 form a matroid whose basis graph is the hypercube . We prove that any -graph of diameter 4 is bipartite self complementary, thus in particular (2,2. Finally, we study some additional properties of (2,2 concerning the order of its automorphism group, girth, domination number, and when being Eulerian.

  13. Multi-diameter pigging: factors affecting the design and selection of pigging tools for multi-diameter pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Dawson, Karl [Pipeline Engineering and Supply Co. Ltd., Richmond, NY (United States)

    2009-07-01

    This paper will consider the process involved in pigging tool selection for pipelines with two or more significant internal diameters which require pigging tools capable of negotiating the different internal diameters whilst also carrying out the necessary pipeline cleaning operation. The paper will include an analysis of pipeline features that affect pigging tool selection and then go on to look at other variables that determine the pigging tool design; this will include a step by step guide outlining how the tool is designed, the development of prototype pigs and the importance of testing and validation prior to final deployment in operational pigging programmes. (author)

  14. Analysis of pumping tests: Significance of well diameter, partial penetration, and noise

    Science.gov (United States)

    Heidari, M.; Ghiassi, K.; Mehnert, E.

    1999-01-01

    The nonlinear least squares (NLS) method was applied to pumping and recovery aquifer test data in confined and unconfined aquifers with finite diameter and partially penetrating pumping wells, and with partially penetrating piezometers or observation wells. It was demonstrated that noiseless and moderately noisy drawdown data from observation points located less than two saturated thicknesses of the aquifer from the pumping well produced an exact or acceptable set of parameters when the diameter of the pumping well was included in the analysis. The accuracy of the estimated parameters, particularly that of specific storage, decreased with increases in the noise level in the observed drawdown data. With consideration of the well radii, the noiseless drawdown data from the pumping well in an unconfined aquifer produced good estimates of horizontal and vertical hydraulic conductivities and specific yield, but the estimated specific storage was unacceptable. When noisy data from the pumping well were used, an acceptable set of parameters was not obtained. Further experiments with noisy drawdown data in an unconfined aquifer revealed that when the well diameter was included in the analysis, hydraulic conductivity, specific yield and vertical hydraulic conductivity may be estimated rather effectively from piezometers located over a range of distances from the pumping well. Estimation of specific storage became less reliable for piezemeters located at distances greater than the initial saturated thickness of the aquifer. Application of the NLS to field pumping and recovery data from a confined aquifer showed that the estimated parameters from the two tests were in good agreement only when the well diameter was included in the analysis. Without consideration of well radii, the estimated values of hydraulic conductivity from the pumping and recovery tests were off by a factor of four.The nonlinear least squares method was applied to pumping and recovery aquifer test data in

  15. Vertebral Artery Diameter and Flow: Nature or Nurture.

    Science.gov (United States)

    Tarnoki, Adam Domonkos; Fejer, Bence; Tarnoki, David Laszlo; Littvay, Levente; Lucatelli, Pierleone; Cirelli, Carlo; Fanelli, Fabrizio; Sacconi, Beatrice; Fagnani, Corrado; Medda, Emanuela; Farina, Filippo; Meneghetti, Giorgio; Horvath, Tamas; Pucci, Giacomo; Schillaci, Giuseppe; Stazi, Maria Antonietta; Baracchini, Claudio

    2017-09-01

    In contrast with the carotid arteries, the vertebral arteries (VAs) show considerable variation in length, caliber, and vessel course. This study investigated whether the variation in diameter and flow characteristics of the VAs might be inherited. A total of 172 Italian twins from Padua, Perugia, and Terni (54 monozygotic, 32 dizygotic) recruited from the Italian Twin Registry underwent B-mode and pulsed-wave Doppler ultrasound assessment of their VAs. VA diameters, peak systolic velocity (PSV) and end diastolic velocity (EDV) were assessed at the level of a horizontal V2 segment. Univariate quantitative genetic modeling was performed. Fourteen percent of the sample had VA hypoplasia. Within pair correlation in monozygotic twins was higher than in dizygotics (.552 vs. .229) for VA diameter. Age- and sex-adjusted genetic effect, under the most parsimonious model, accounted for 54.7% (95% CI: 42.2-69.1%) of the variance of VA diameter, and unshared environmental effect for 45.3% (95% CI: 30.9-57.8%). No heritability was found for the PSV of VA, but shared (34.1%; 95% CI: 16.7-53.7%) and unshared (65.9%; 95% CI: 45.9-83.1%) environmental factors determined the variance. EDV of VA is moderately genetically influenced (42.4%; 95% CI: 16.1-64.9%) and also determined by the unshared environment (57.6%; 95% CI: 34.7-83.7%). The diameter of the VAs is moderately genetically determined. Different factors influence the PSV and EDV of VAs, which may highlight the complex hemodynamic background of VA flow and help to understand the vertebral flow anomalies found by ultrasound. Copyright © 2017 by the American Society of Neuroimaging.

  16. Stand diameter distribution modelling and prediction based on Richards function.

    Directory of Open Access Journals (Sweden)

    Ai-guo Duan

    Full Text Available The objective of this study was to introduce application of the Richards equation on modelling and prediction of stand diameter distribution. The long-term repeated measurement data sets, consisted of 309 diameter frequency distributions from Chinese fir (Cunninghamia lanceolata plantations in the southern China, were used. Also, 150 stands were used as fitting data, the other 159 stands were used for testing. Nonlinear regression method (NRM or maximum likelihood estimates method (MLEM were applied to estimate the parameters of models, and the parameter prediction method (PPM and parameter recovery method (PRM were used to predict the diameter distributions of unknown stands. Four main conclusions were obtained: (1 R distribution presented a more accurate simulation than three-parametric Weibull function; (2 the parameters p, q and r of R distribution proved to be its scale, location and shape parameters, and have a deep relationship with stand characteristics, which means the parameters of R distribution have good theoretical interpretation; (3 the ordinate of inflection point of R distribution has significant relativity with its skewness and kurtosis, and the fitted main distribution range for the cumulative diameter distribution of Chinese fir plantations was 0.4∼0.6; (4 the goodness-of-fit test showed diameter distributions of unknown stands can be well estimated by applying R distribution based on PRM or the combination of PPM and PRM under the condition that only quadratic mean DBH or plus stand age are known, and the non-rejection rates were near 80%, which are higher than the 72.33% non-rejection rate of three-parametric Weibull function based on the combination of PPM and PRM.

  17. Stand diameter distribution modelling and prediction based on Richards function.

    Science.gov (United States)

    Duan, Ai-guo; Zhang, Jian-guo; Zhang, Xiong-qing; He, Cai-yun

    2013-01-01

    The objective of this study was to introduce application of the Richards equation on modelling and prediction of stand diameter distribution. The long-term repeated measurement data sets, consisted of 309 diameter frequency distributions from Chinese fir (Cunninghamia lanceolata) plantations in the southern China, were used. Also, 150 stands were used as fitting data, the other 159 stands were used for testing. Nonlinear regression method (NRM) or maximum likelihood estimates method (MLEM) were applied to estimate the parameters of models, and the parameter prediction method (PPM) and parameter recovery method (PRM) were used to predict the diameter distributions of unknown stands. Four main conclusions were obtained: (1) R distribution presented a more accurate simulation than three-parametric Weibull function; (2) the parameters p, q and r of R distribution proved to be its scale, location and shape parameters, and have a deep relationship with stand characteristics, which means the parameters of R distribution have good theoretical interpretation; (3) the ordinate of inflection point of R distribution has significant relativity with its skewness and kurtosis, and the fitted main distribution range for the cumulative diameter distribution of Chinese fir plantations was 0.4∼0.6; (4) the goodness-of-fit test showed diameter distributions of unknown stands can be well estimated by applying R distribution based on PRM or the combination of PPM and PRM under the condition that only quadratic mean DBH or plus stand age are known, and the non-rejection rates were near 80%, which are higher than the 72.33% non-rejection rate of three-parametric Weibull function based on the combination of PPM and PRM.

  18. Arteriolar Diameters in Glaucomatous Eyes with Single-Hemifield Damage.

    Science.gov (United States)

    Russo, Andrea; Costagliola, Ciro; Rizzoni, Damiano; Ghilardi, Nausica; Turano, Raffaele; Semeraro, Francesco

    2016-05-01

    To examine the association between retinal arteriolar caliber and lumen, retinal sensitivity (RS), and retinal nerve fiber layer (RNFL) thickness in glaucomatous eyes with single-hemifield loss. We conducted a prospective, nonrandomized, case-control study of 20 eyes of 20 patients with glaucoma with visual field damage confined to a single hemifield. The control group was composed of 20 eyes of 20 normal subjects. For all the eyes, we performed optical coherence tomography to assess the RNFL and standard automated perimetry to evaluate RS. External and internal arteriolar diameters were assessed in vivo using scanning laser Doppler flowmetry. The RNFL was significantly thinner in glaucomatous eyes than in normal eyes (p < 0.001). In glaucomatous eyes, a positive correlation between sectorial RNFL thickness and the corresponding external and internal arteriolar diameters was found (r = 0.43, p = 0.05; r = 0.63, p = 0.003, respectively). The internal arteriolar diameter significantly correlated with RS in the corresponding abnormal hemifield (r = 0.44, p = 0.04). Compared with the normal hemifield, the internal arteriolar diameter, RNFL thickness, and RS were significantly reduced, whereas the external arteriolar diameter was unchanged in the abnormal hemifield. In glaucomatous eyes with single-hemifield damage, attenuation of retinal vessels was associated with a thinner RNFL and reduced RS. Moreover, a narrower lumen with increased wall-to-lumen ratio was found in the abnormal hemifield, supporting the hypothesis that vessel narrowing is likely secondary to a lower demand for blood flow in the glaucomatous areas of the retina.

  19. Measurement error in CT assessment of appendix diameter

    Energy Technology Data Exchange (ETDEWEB)

    Trout, Andrew T.; Towbin, Alexander J. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, MLC 5031, Cincinnati, OH (United States); Zhang, Bin [Cincinnati Children' s Hospital Medical Center, Department of Biostatistics and Epidemiology, Cincinnati, OH (United States)

    2016-12-15

    Appendiceal diameter continues to be cited as an important criterion for diagnosis of appendicitis by computed tomography (CT). To assess sources of error and variability in appendiceal diameter measurements by CT. In this institutional review board-approved review of imaging and medical records, we reviewed CTs performed in children <18 years of age between Jan. 1 and Dec. 31, 2010. Appendiceal diameter was measured in the axial and coronal planes by two reviewers (R1, R2). One year later, 10% of cases were remeasured. For patients who had multiple CTs, serial measurements were made to assess within patient variability. Measurement differences between planes, within and between reviewers, within patients and between CT and pathological measurements were assessed using correlation coefficients and paired t-tests. Six hundred thirty-one CTs performed in 519 patients (mean age: 10.9 ± 4.9 years, 50.8% female) were reviewed. Axial and coronal measurements were strongly correlated (r = 0.92-0.94, P < 0.0001) with coronal plane measurements significantly larger (P < 0.0001). Measurements were strongly correlated between reviewers (r = 0.89-0.9, P < 0.0001) but differed significantly in both planes (axial: +0.2 mm, P=0.003; coronal: +0.1 mm, P=0.007). Repeat measurements were significantly different for one reviewer only in the axial plane (0.3 mm difference, P<0.05). Within patients imaged multiple times, measured appendix diameters differed significantly in the axial plane for both reviewers (R1: 0.5 mm, P = 0.031; R2: 0.7 mm, P = 0.022). Multiple potential sources of measurement error raise concern about the use of rigid diameter cutoffs for the diagnosis of acute appendicitis by CT. (orig.)

  20. Maximum diameter of the rod-shaped specimen for transmission electron microtomography without the 'missing wedge'

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Mitsuro [Department of Macromolecular Science and Engineering, Graduate School of Science and Engineering, Kyoto Institute of Technology, Matsugasaki, Kyoto 606-8585 (Japan); Research and Development Department, Nitto Analytical Techno-Center Co., Ltd., 1-1-2, Shimohozumi, Ibaraki-city, Osaka 567-8680 (Japan); Kawase, Noboru [Research and Development Department, Nitto Analytical Techno-Center Co., Ltd., 1-1-2, Shimohozumi, Ibaraki-city, Osaka 567-8680 (Japan); Kaneko, Takeshi [Department of Macromolecular Science and Engineering, Graduate School of Science and Engineering, Kyoto Institute of Technology, Matsugasaki, Kyoto 606-8585 (Japan); Toh, Shoichi; Matsumura, Syo [Research Laboratory of High-Voltage Electron Microscope, Kyushu University, 6-10-1, Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan); Jinnai, Hiroshi [Department of Macromolecular Science and Engineering, Graduate School of Science and Engineering, Kyoto Institute of Technology, Matsugasaki, Kyoto 606-8585 (Japan)], E-mail: hjinnai@kit.ac.jp

    2008-02-15

    In our recent study, the complete rotation of a rod-shaped specimen during transmission electron microscopy (TEM) has been successfully carried out, yielding a truly quantitative three-dimensional (3D) structure of a ZrO{sub 2}/polymer nano-composite. This result allows the further development of transmission electron microtomography (TEMT) for materials science. The diameter of the rod-shaped specimen was about 150 nm, which may not be statistically large enough to evaluate structural parameters, e.g., volume fraction of Zr nano-particles. Thus, it is preferable to image rods with larger diameters in 3D. In this study, several rod-shaped specimens whose diameters ranged from 150 to 530 nm were subjected to the 'distortion-free TEMT'. The maximum diameters, l, observable under 200 and 300 kV-TEMTs were, respectively, 460-470 and 600-670 nm (corresponding the maximum relative diameters, l/{lambda} ({lambda}: mean free path), were ca. 2.2 and 2.7-3.0)

  1. Effect of Crucible Diameter Reduction on the Convection, Macrosegregation, and Dendritic Morphology during Directional Solidification of Pb-2.2 Wt Pct Sb Alloy

    Science.gov (United States)

    Chen, Jun; Tewari, S. N.; Magadi, G.; DeGroh, H. C., III

    2003-01-01

    The Pb-2.2 wt pct Sb alloy has been directionally solidified in 1-, 2-, 3-, and 7-mm-diameter crucibles with planar and dendritic liquid-solid interface orphology. For plane front solidification, the experimentally observed macrosegregation along the solidified length follows the relationship proposed by Favier. Application of a 0.4 T transverse magnetic field has no effect on the extent of convection. Reducing the ampoule diameter appears to decrease the extent of convection. However, extensive convection is still present even in the 1-mm-diameter crucible. An extrapolation of the observed behavior indicated that nearly diffusive transport conditions require ampoules that are about 40 microns in diameter. Reduction of the crucible diameter does not appear to have any significant effect on the primary dendrite spacing. However, it results in considerable distortion of the dendrite morphology and ordering. This is especially true for the 1-mm diameter samples.

  2. Analysis of the radius and diameter protocols in terms of pricing telecommunication services

    Directory of Open Access Journals (Sweden)

    Vesna M. Radonjić

    2013-06-01

    functionality are based on the fundamental functionality of the RADIUS protocol and the rest is a result of new solutions and improvements to the existing ideas. The Diameter protocol focuses on the expansion of flexible, advanced routing algorithms, dynamic troubleshooting and safety characteristics of the transport layer. This paper defines the basic packet formats, data transfer mechanisms and error management, methods of communication between individual elements of the architecture and basic security functions. The Diameter protocol architecture is based on the peer-to-peer model. Besides clients and servers, network agents can be the elements of this architecture. The Diameter agent is an element that does not allow authentication / authorization locally, but the server performs this operation, while one node can be both the client and the server simultaneously. The role of agents can be forwarding (Relay Agent, redirection (Redirect Agent, mediation (Proxy Agent and translation (Translation Agent. Since the peer-to-peer model is applied, each Diameter element can establish more connections at the same time. Diameter enables the delivery of attribute value pairs, the possibility of negotiation, error notification, extensibility by adding new commands and attribute value pairs, the basic services necessary for applications such as managing user sessions or accounting.   Comparison of the RADIUS and Diameter protocols   Although at the protocol market for authentication, authorization and accounting, the RADIUS protocol remains the most popular, its popularity and dominance has a decreasing tendency. The main reasons for this are more prominent limitations which are particularly perceived due to new and increasingly popular technology. Therefore, the main issue is about a protocol that will replace RADIUS. The peer-to-peer architecture used by Diameter is much more flexible than the client-server model because in the peer-to-peer architecture every element can be both the

  3. Aneurysm diameter and proximal aortic neck diameter influence clinical outcome of endovascular abdominal aortic repair : A 4-year EUROSTAR experience

    NARCIS (Netherlands)

    Waasdorp, EJ; de Vries, JPPM; Hobo, R; Leurs, LJ; Buth, J; Moll, FL

    2005-01-01

    Our objective was to evaluate the effect of preoperative aneurysm and aortic neck diameter on clinical outcome after infrarenal abdominal endovascular aneurysm repair (EVAR). Data of patients in the European Collaborators Registry on Stent-Graft Techniques for Abdominal Aortic Aneurysm Repair (EUROS

  4. Anatomical evaluation of the root canal diameter and root thickness on the apical third of mesial roots of molars.

    Science.gov (United States)

    Martos, Josué; Tatsch, Gustavo Henrique; Tatsch, Augusto César; Silveira, Luiz Fernando Machado; Ferrer-Luque, Carmen María

    2011-09-01

    The purpose was to determine the diameter of the main root canal and wall thickness in the apical dentin in mesial roots of maxillary and mandibular molars. Forty mesiobuccal and mesial root specimens were sectioned horizontally at 1, 2 and 3 mm from the apex, and measured at each top surface by using optical microscopy to an accuracy of ×20 magnification. The anatomical parameters were established as the following points of reference: AB, two points connected by a line from the outer edge of the mesial wall to the outer edge of the distal one through the center of the root canal to measure the thickness of the root and mesiodistal diameter of the root canal (CD). A second line (EF) was designed to evaluate the diameter of the root canal in the buccolingual direction. All data were summarized, and values were assessed statistically by ANOVA and Bonferroni multiple comparisons. The buccolingual (BL) root canal diameters at 1, 2 and 3 mm in the mandibular and maxillary molars were greater than in the mesiodistal (MD), showing statistically significant differences (p maxillary molars were statistically significant (p maxillary molars was 1.741 mm. The BL diameters in maxillary and mandibular molars were higher than the MD diameter. The thickness (MD) of maxillary and mandibular molars decreased as a function of apical proximity.

  5. Tunable diameter electrostatically formed nanowire for high sensitivity gas sensing

    Institute of Scientific and Technical Information of China (English)

    Alex Henning; Nandhini Swaminathan; Andrey Godkin; Gil Shalev; Iddo Amit; Yossi Rosenwaks

    2015-01-01

    We report on an electrostatically formed nanowire (EFN)-based sensor with tunable diameters in the range of 16 nm to 46 nm and demonstrate an EFN- based field-effect transistor as a highly sensitive and robust room temperature gas sensor. The device was carefully designed and fabricated using standard integrated processing to achieve the 16 nm EFN that can be used for sensing without any need for surface modification. The effective diameter for the EFN was determined using Kelvin probe force microscopy accompanied by three- dimensional electrostatic simulations. We show that the EFN transistor is capable of detecting 100 parts per million of ethanol gas with bare SiO2.

  6. Angular diameter distances reconsidered in the Newman and Penrose formalism

    CERN Document Server

    Kling, Thomas P

    2016-01-01

    Using the Newman and Penrose spin coefficient (NP) formalism, we provide a derivation of the Dyer-Roeder equation for the angular diameter distance in cosmological space-times. We show that the geodesic deviation equation written in NP formalism is precisely the Dyer-Roeder equation for a general Friedman-Robertson-Walker (FRW) space-time, and then we examine the angular diameter distance to redshift relation in the case that a flat FRW metric is perturbed by a gravitational potential. We examine the perturbation in the case that the gravitational potential exhibits the properties of a thin gravitational lens, demonstrating how the weak lensing shear and convergence act as source terms for the perturbed Dyer-Roeder equation.

  7. Visual function and retinal vessel diameters during hyperthermia in man

    DEFF Research Database (Denmark)

    Jensen, Bettina Hagström; Bram, Thue; Kappelgaard, Per

    2017-01-01

    laser ophthalmoscopy was used to measure retinal trunk vessel diameters. Assessment was made at baseline, during hyperthermia and after cooling. RESULTS: The induction of a mean increase in core body temperature of 1.02°C was associated with a 7.15-mmHg mean reduction in systolic blood pressure (p ... in cling film, tinfoil and warming blankets. Subsequent cooling was achieved by undressing. Flicker sensitivity (critical flicker fusion frequency) was chosen to assess temporal resolution, while the Freiburg Vision Test was used to determine spatial contrast sensitivity at 1.5 cycles per degree. Scanning...... diameters (CI95 0.96-4.94, p cooling. CONCLUSION: Increased core body temperature was accompanied by improved temporal visual resolution and retinal trunk...

  8. Experimental study on the influence of wire diameter on the internal flow behaviour of woven metal screens

    Science.gov (United States)

    Peng, Y. B.; Xu, G. Q.; Luo, X.; Li, H. W.; Liu, Y. P.

    2017-01-01

    Sintered woven wire mesh structures are a classic porous medium. In this paper, we examined the internal flow behaviours of sintered metal wire mesh structures with 0.215mm diameter wires with different porosities. Following previous research results, the influence of woven mesh wire diameter on material penetrating quality was studied. The air that was applied by the gas source was used to investigate structure performance. The Reynolds numbers of the inlet changed from 8.2 to 66.1. The pressures and flow rate at the inlet and outlet were obtained to calculate the permeability and inertia coefficient of each specimen, as well as the friction factors. The experiment results showed that permeability increased and the inertia coefficient decreased as wire diameter increased. Moreover, structures with large wire diameters (d s = 0.215mm) showed better penetrating quality at the same porosity levels. Increases in pressure drop kept pace with increases in diameter. The friction factor decreased as the Reynolds number increased, and tended to be constant.

  9. Consequences of the Continuity of the Monic Integer Transfinite Diameter

    CERN Document Server

    Hilmar, Jan

    2007-01-01

    We consider the problem of determining the monic integer transfinite diameter t_M(I)&=&\\lim_{n\\to\\infty}\\inf_{p_n\\in{\\mathcal M_n}}\\supnorm{p_n}{I}^{1/n} for real intervals of length less than 4. We show the $t_M([0,x])$, as a function in $x>0$, is continuous, therefore disproving two conjectures due to Hare and Smyth. Consequently, for $n>2\\in\

  10. A study of the heated length to diameter effects

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong Ho; Baek, Won Pil; Chang, Soon Heung [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1997-12-31

    An analytical and experimental investigation has been performed on the heated length-to-diameter effect on critical heat flux exit conditions. A L/D correction factor is developed by applying artificial neural network and conventional regression techniques to the KAIST CHF data base. In addition, experiment is being performed to validate the developed L/D correction factor with independent data. Assessment shows that the developed correction factor is promising for practical applications. 6 refs., 8 figs. (Author)

  11. Uncertainty budget for optical coordinate measurements of circle diameter

    DEFF Research Database (Denmark)

    Morace, Renate Erica; Hansen, Hans Nørgaard; De Chiffre, Leonardo

    2004-01-01

    An uncertainty analysis for circle diameter measurements using a coordinate measuring machine (CMM) equipped with an optical probe is presented in this paper. A mathematical model for data evaluation and uncertainty assessment was formulated in accordance with Guide to the Expression of Uncertainty...... in Measurement (GUM). Various input quantities such as CCD camera resolution, influence of illuminating system, CMM errors etc. were considered in the model function and experimentally investigated....

  12. Pupil Center as a Function of Pupil Diameter

    DEFF Research Database (Denmark)

    Ahmed, Zaheer; Mardanbegi, Diako; Hansen, Dan Witzner

    2016-01-01

    We investigate the gaze estimation error induced by pupil size changes using simulated data. We investigate the influence of pupil diameter changes on estimated gaze point error obtained by two gaze estimation models. Simulation data show that at wider viewing angles and at small eye......-camera distances, error increases with increasing pupil sizes. The maximum error recorded for refracted pupil images is 2.4° of visual angle and 1.5° for non-refracted pupil projections....

  13. THE CUTWIDTH OF TREES WITH DIAMETER AT MOST 4

    Institute of Scientific and Technical Information of China (English)

    LinYixun

    2003-01-01

    The cutwidth problem for a graph G is to embed G into a path Pn such that the maximum number of overlap edges (i. e. , the congestion) is minimized. It is known that the problem for general graphs is NP-hard while it is polynomially solvable for trees. This paper presents an exact formula for the cutwidth of trees with diameter at most 4. A relation with the bandwidth is discussed as well.

  14. Visual function and retinal vessel diameters during hyperthermia in man.

    Science.gov (United States)

    Jensen, Bettina Hagström; Bram, Thue; Kappelgaard, Per; Arvidsson, Henrik; Loskutova, Ekaterina; Munch, Inger Christine; Larsen, Michael

    2016-12-21

    To assess the effect of elevated core body temperature on temporal and spatial contrast sensitivity and retinal vessel diameters. The study included 13 healthy volunteers aged 20-37 years. Core body temperature elevation (target +1.1°C) was induced by wrapping the participants in cling film, tinfoil and warming blankets. Subsequent cooling was achieved by undressing. Flicker sensitivity (critical flicker fusion frequency) was chosen to assess temporal resolution, while the Freiburg Vision Test was used to determine spatial contrast sensitivity at 1.5 cycles per degree. Scanning laser ophthalmoscopy was used to measure retinal trunk vessel diameters. Assessment was made at baseline, during hyperthermia and after cooling. The induction of a mean increase in core body temperature of 1.02°C was associated with a 7.15-mmHg mean reduction in systolic blood pressure (p < 0.01), a 10.6-mmHg mean reduction in diastolic blood pressure (p < 0.01), a mean increase in pulse rate of 36.3 bpm (p < 0.0001), a 2.66% improvement in flicker sensitivity (CI95 1.37-3.94, p < 0.001), a 2.80% increase in retinal artery diameters (CI95 1.09-4.51, p < 0.01) and a 2.95% increase in retinal vein diameters (CI95 0.96-4.94, p < 0.01). There was no detectable effect of temperature on spatial contrast sensitivity. All ocular test parameters returned to baseline levels after cooling. Increased core body temperature was accompanied by improved temporal visual resolution and retinal trunk vessel dilation. The results suggest that hyperthermia is associated with enhanced retinal function and increased retinal metabolism. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  15. PREPARATION AND ADSORBABILITY OF DEXTRAN MICROSPHERES WITH UNIFORM DIAMETER

    Institute of Scientific and Technical Information of China (English)

    Ri-sheng Yao; Wen-xia Gao; Jing Sun; Ya-hua You

    2005-01-01

    The method of preparing uniform dextran microspheres with a narrow diameter distribution was introduced and the adsorbability of these microspheres was evaluated. The microspheres were prepared in W/O microemulsion using 0.5% dextran solution as the aqueous phase and n-hexane as the oil phase. Characteristics of the prepared dextran microspheres were examined with laser light blocking technique, optical microscope and ultraviolet spectrometer. The results show that the prepared dextran microspheres have uniform morphology and narrow diameter distribution, nearly 92% of them having a diameter of 56.6 μm. In vitro evaluation of adsorbability, wet dextran microspheres have good adsorption of 98.32 mg/g of model drug methylene blue in 20.86 mg/L methylene blue solution at 25℃. The adsorption of dried dextran microspheres under the same condition is 132.15 mg/g, which is even higher. And the adsorbability of dextran microspheres has significant relationship with the concentration of methylene blue and temperature. The adsorbability is better at lower temperature and higher concentration of methylene blue.

  16. Time-delay Cosmography: Increased Leverage with Angular Diameter Distances

    CERN Document Server

    Jee, Inh; Suyu, Sherry H; Huterer, Dragan

    2015-01-01

    Strong lensing time-delay systems constrain cosmological parameters via the so-called time-delay distance and the angular diameter distance to the lens. In previous studies, only the former information was used. In this paper, we show that the cosmological constraints improve significantly when the latter information is also included. Specifically, the angular diameter distance plays a crucial role in breaking the degeneracy between the curvature of the Universe and the time-varying equation of state of dark energy. Using a mock sample of 55 bright quadruple lens systems based on expectations for ongoing/future imaging surveys, we find that adding the angular diameter distance information to the time-delay distance information and the cosmic microwave background data of Planck improves the constraint on the constant equation of state by 30%, on the time variation in the equation of state by a factor of two, and on the Hubble constant in the flat $\\Lambda$CDM model by a factor of two. Therefore, previous forec...

  17. Time-delay cosmography: increased leverage with angular diameter distances

    Science.gov (United States)

    Jee, I.; Komatsu, E.; Suyu, S. H.; Huterer, D.

    2016-04-01

    Strong lensing time-delay systems constrain cosmological parameters via the so-called time-delay distance and the angular diameter distance to the lens. In previous studies, only the former information was used in forecasting cosmographic constraints. In this paper, we show that the cosmological constraints improve significantly when the latter information is also included. Specifically, the angular diameter distance plays a crucial role in breaking the degeneracy between the curvature of the Universe and the time-varying equation of state of dark energy. Using a mock sample of 55 bright quadruple lens systems based on expectations for ongoing/future imaging surveys, we find that adding the angular diameter distance information to the time-delay distance information and the Planck's measurements of the cosmic microwave background anisotropies improves the constraint on the constant equation of state by 30%, on the time variation in the equation of state by a factor of two, and on the Hubble constant in the flat ΛCDM model by a factor of two. Therefore, previous forecasts for the statistical power of time-delay systems were overly pessimistic, i.e., time-delay systems are more powerful than previously appreciated.

  18. Real-time diameter measurement using diffuse light

    Science.gov (United States)

    Luo, Xiaohe; Hui, Mei; Zhu, Qiudong; Wang, Shanshan

    2016-09-01

    A method for on-line rapid determination of the diameter of metallic cylinder is introduced in this paper. Under the radiation of diffuse light, there is a bright area close to the margin of metallic cylinder, and the method of this paper is based on the intensity distribution of the bright area. In this paper, with the radiation by a diffuse plane light with special shape, we present the relation expression of the distance between the peak point and the real edge of the cylinder and the distance between the diffuse light and the pinhole aperture of the camera. With the expression, the diameter of the cylinder to be measured can be calculated. In the experiments, monochromatic LED uniting with ground glass forms the diffuse light source, then the light irradiates the tested cylinder. After the cylinder, we use a lens with a front pinhole stop to choose the light into CMOS, then a computer is used to analyze images and export the measurement results. The measuring system using this method is very easily implemented, so it can realize the on-line rapid measurement. Experimental results are presented for six metallic cylinders with the diameter in 5 18mm range and roughness in Ra- 0.02um, and the precision reaches 3um.

  19. The Effects of Post Diameter on Stress Distribution in Maxillary Central Incisor, A Three Dimensional Finite Element Study

    Directory of Open Access Journals (Sweden)

    A. Monzavi

    2004-06-01

    Full Text Available Statement of Problem: Currently there are three recognized theories about the diameter of prepared dowel space in endodontically treated teeth. Diameter of the dowel is commonly contributed to the root fracture.Purpose: This study used a 3 dimensional (3D finite element method to predict stress distribution in endodontically treated central maxillary tooth with cast post and core with various post diameter according to three philosophies about post diameter (Conservational,Proportional, Preservational.Materials and Methods: In this study three 3D models of central maxillary incisors with different post diameter were created and depend on the size of post called narrow, medium and thick model with post diameter of 1.1mm, 1.7 mm and 2.6 mm of in (CEJrespectively. A load of 100 N was applied to cingulum fossa from lingual direction with 45-degree angle to long axis of tooth and maximum tensile, compressive and Von Misses stresses and their distribution in dentin and post was studied.Results: The post in narrow, medium and thick models produced a similar magnitude of tensile, compressive and Von Misses stresses in dentin. Stress distribution was also similar in all models. Peak stresses in dentin were slightly decreased when post diameter increased from narrow to thick model. In all models peak tensile stresses in dentin occurred in the coronally one third of the lingual surface of the root, whereas peak compressive stresseswere evident in the coronal one third of the facial surface of the root.Conclusion: There were not significant differences stress distribution pattern and magnitude in dentin between the three theories of post diameter.

  20. Spatial characteristics of tree diameter distributions in a temperate old-growth forest.

    Science.gov (United States)

    Zhang, Chunyu; Wei, Yanbo; Zhao, Xiuhai; von Gadow, Klaus

    2013-01-01

    This contribution identifies spatial characteristics of tree diameter in a temperate forest in north-eastern China, based on a fully censused observational study area covering 500×600 m. Mark correlation analysis with three null hypothesis models was used to determine departure from expectations at different neighborhood distances. Tree positions are clumped at all investigated scales in all 37 studied species, while the diameters of most species are spatially negatively correlated, especially at short distances. Interestingly, all three cases showing short-distance attraction of dbh marks are associated with light-demanding shrub species. The short-distance attraction of dbh marks indicates spatially aggregated cohorts of stems of similar size. The percentage of species showing significant dbh suppression peaked at a 4 m distance under the heterogeneous Poisson model. At scales exceeding the peak distance, the percentage of species showing significant dbh suppression decreases sharply with increasing distances. The evidence from this large observational study shows that some of the variation of the spatial characteristics of tree diameters is related variations of topography and soil chemistry. However, an obvious interpretation of this result is still lacking. Thus, removing competitors surrounding the target trees is an effective way to avoid neighboring competition effects reducing the growth of valuable target trees in forest management practice.

  1. Middle cerebral artery diameter changes during rhythmic handgrip exercise in humans.

    Science.gov (United States)

    Verbree, J; Bronzwaer, Agt; van Buchem, M A; Daemen, Mjap; van Lieshout, J J; van Osch, Mjp

    2017-08-01

    Transcranial Doppler (TCD) sonography is a frequently employed technique for quantifying cerebral blood flow by assuming a constant arterial diameter. Given that exercise increases arterial pressure by sympathetic activation, we hypothesized that exercise might induce a change in the diameter of large cerebral arteries. Middle cerebral artery (MCA) cross-sectional area was assessed in response to handgrip exercise by direct magnetic resonance imaging (MRI) observations. Twenty healthy subjects (11 female) performed three 5 min bouts of rhythmic handgrip exercise at 60% maximum voluntary contraction, alternated with 5 min of rest. High-resolution 7 T MRI scans were acquired perpendicular to the MCA. Two blinded observers manually determined the MCA cross-sectional area. Sufficient image quality was obtained in 101 MCA-scans of 19 subjects (age-range 20-59 years). Mixed effects modelling showed that the MCA cross-sectional area decreased by 2.1 ± 0.8% (p = 0.01) during handgrip, while the heart rate increased by 11 ± 2% (p exercise. This further strengthens the current concept of sympathetic control of large cerebral arteries, showing in vivo vasoconstriction during exercise-induced sympathetic activation. Moreover, care must be taken when interpreting TCD exercise studies as diameter constancy cannot be assumed.

  2. Bearing Capacities of Different-Diameter Concrete-Filled Steel Tubes under Axial Compression

    Directory of Open Access Journals (Sweden)

    Wenjing Wang

    2016-01-01

    Full Text Available The bearing capacities of concrete-filled steel tubes are normally derived through experiments with small-scale specimens, but it is uncertain whether such derivations are appropriate for the much larger components used in practical engineering. This study therefore investigates the effect of different diameters (219, 426, 630, and 820 mm on the axial compression of short concrete columns in steel (Q235 tubes. It is found that the peak nominal stress decreases with increasing specimen size and that the axial bearing capacity is determined by three separate components: the cylinder compressive strength of the concrete, the improvement in strength due to the confining effect of the steel tube, and the longitudinal strength of the steel tube. At peak load, increases in the specimen diameter reduce the hoop stresses in the steel tube, thereby reducing the strengthening effect of confinement. Vertical stress in the steel tube is increased with diameter; therefore, the axial bearing capacity of the steel tube is directly related to the specimen size. Size effect coefficients for these three aspects of bearing capacity are defined and used to develop a size-dependent model for predicting the axial bearing capacity of large, concrete-filled steel tubes. The model is then validated against experimental data.

  3. Large Wood Storage Does Not Decrease Downstream Through a Watershed

    Science.gov (United States)

    Vaughan, M.; Pasternack, G. B.; Senter, A. E.; Dahlke, H. E.

    2013-12-01

    The storage of large wood in streams at the watershed scale has long been characterized as decreasing downstream due to a transport limitation in headwater streams, and a supply limitation in larger rivers. The objective of this study was to test this hypothesis through a field study in the Upper Yuba River watershed in Northern California, USA. While most studies surveyed within the wetted channel at selected reaches of different sizes, this study measured overbank deposits of large wood in addition to those in-channel to reflect the total storage within the active river corridor, and used a stratified random sampling scheme to see if relations held at the watershed scale. The watershed is large (2,874 km2), mountainous, mostly forested, and has been dramatically altered by human activities primarily related to gold mining. One hundred fourteen field sites of varied drainage area sizes were visited, inventoried for large wood (length > 1 m, diameter > 10 cm) storage within the active river corridor, and the volume storage per river length was calculated. Inclusion of floodplains in field surveys illuminates the fact that the distribution of large wood changes within the active river corridor, while the total storage does not decrease downstream. Among many watershed-scale control variables, such as drainage area, stream order, and upslope distance, the local amount of shrub cover and bankfull channel width were the only significant predictors of large wood storage in a multiple linear regression model, both with positive coefficients. A critical literature review was also conducted to investigate the evidence for the common conceptual model. Findings were that (1) the observed downstream trend of large wood storage is largely a function of the methods employed by each study, (2) the use of storage per channel area has confounded the commonly held conceptual model, due to its correlation with channel width, and (3) there is little evidence to support the hypothesis

  4. Strain analysis of different diameter Morse taper implants under overloading compressive conditions

    Directory of Open Access Journals (Sweden)

    Carolina Guimarães CASTRO

    2015-01-01

    Full Text Available The aim of this study was to evaluate the amount of deformation from compression caused by different diameters of Morse taper implants and the residual deformation after load removal. Thirty Morse taper implants lacking external threads were divided into 3 groups (n = 10 according to their diameter as follows: 3.5 mm, 4.0 mm and 5.0 mm. Two-piece abutments were fixed into the implants, and the samples were subjected to compressive axial loading up to 1500 N of force. During the test, one strain gauge remained fixed to the cervical portion of each implant to measure the strain variation. The strain values were recorded at two different time points: at the maximum load (1500 N and 60 seconds after load removal. To calculate the strain at the implant/abutment interface, a mathematical formula was applied. Data were analyzed using a one-way Anova and Tukey’s test (α = 0.05. The 5.0 mm diameter implant showed a significantly lower strain (650.5 μS ± 170.0 than the 4.0 mm group (1170.2 μS ± 374.7 and the 3.5 mm group (1388.1 μS ± 326.6 (p < 0.001, regardless of the load presence. The strain values decreased by approximately 50% after removal of the load, regardless of the implant diameter. The 5.0 mm implant showed a significantly lower strain at the implant/abutment interface (943.4 μS ± 504.5 than the 4.0 mm group (1057.4 μS ± 681.3 and the 3.5 mm group (1159.6 μS ± 425.9 (p < 0.001. According to the results of this study, the diameter influenced the strain around the internal and external walls of the cervical region of Morse taper implants; all diameters demonstrated clinically acceptable values of strain.

  5. Plasma volume changes during hypoglycaemia

    DEFF Research Database (Denmark)

    Hilsted, J; Bendtsen, F; Christensen, N J

    1990-01-01

    To investigate whether previously reported changes in venous blood volume and composition induced by acute hypoglycaemia in humans are representative for the entire body we measured erythrocyte 51Cr content, haematocrit, plasma volume, intravascular albumin content and transcapillary escape rate...... of albumin in arterial and venous blood in seven healthy subjects before and during insulin-induced hypoglycaemia. In both vascular sites blood 51Cr content and the haematocrit increased, plasma volume and intravascular albumin content decreased and the transcapillary escape rate of albumin increased during...

  6. Blackcurrant Alters Physiological Responses and Femoral Artery Diameter during Sustained Isometric Contraction

    Directory of Open Access Journals (Sweden)

    Matthew David Cook

    2017-05-01

    Full Text Available Blackcurrant is rich in anthocyanins that may affect exercise-induced physiological responses. We examined tissue oxygen saturation, muscle activity, cardiovascular responses and femoral artery diameter during a submaximal sustained isometric contraction. In a randomised, double-blind, crossover design, healthy men (n = 13, age: 25 ± 4 years, BMI: 25 ± 3 kg·m−2, mean ± SD ingested New Zealand blackcurrant (NZBC extract (600 mg∙day−1 CurraNZ™ or placebo (PL for 7-days separated by 14-days washout. Participants produced isometric maximal voluntary contractions (iMVC and a 120-s 30%iMVC of the quadriceps with electromyography (EMG, near-infrared spectroscopy, hemodynamic and ultrasound recordings. There was no effect of NZBC extract on iMVC (NZBC: 654 ± 73, PL: 650 ± 78 N. During the 30%iMVC with NZBC extract, total peripheral resistance, systolic, diastolic, and mean arterial pressure were lower with increased cardiac output and stroke volume. With NZBC extract, EMG root mean square of the vastus medialis and muscle oxygen saturation were lower with higher total haemoglobin. During the 30%iMVC, femoral artery diameter was increased with NZBC extract at 30 (6.9%, 60 (8.2%, 90 (7.7% and 120 s (6.0%. Intake of NZBC extract for 7-days altered cardiovascular responses, muscle oxygen saturation, muscle activity and femoral artery diameter during a 120-s 30%iMVC of the quadriceps. The present study provides insight into the potential mechanisms for enhanced exercise performance with intake of blackcurrant.

  7. Suitability of Stem Diameter Variations as an Indicator of Water Stress of Cotton

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ji-yang; DUAN Ai-wang; MENG Zhao-jiang; LIU Zu-gui

    2006-01-01

    Water stress effects on stem diameter variations (SDV) were studied in a pot experiment on cotton (Gossypium hirustum L. Meimian99B). Water restriction was imposed at the flowering stage and were compared with a well-watered control treatment. The volumetric soil water content (θv) and SDV were monitored continuously. The objective was to determine the feasibility of using the parameters derived from stem diameter measurements, including maximum daily stem shrinkage (MDS), maximum daily stem diameter (MXSD), and minimum daily stem diameter (MNSD) as indicators of plant water stress. The different behavior of SDV was founded at different growth stages. At stem-maturing stage, MDS increased and MNSD decreased in deficit-irrigated plants compared with the control plants, therefore, it appeared that MDS and MNSD ccould be used as available indicators of plant water status. At stem growth stage, there were no significant differences in MDS values between treatments but MXSD and MNSD responded sharply to soil water deficits. Thus, for rapidly growing cotton, the course of MXSD or MNSD with time offered a consistent stress indicator. SDV was also closely related to atmospheric factors, solar radiation (Rs) and vapor pressure deficit (VPD) were found to be the predominant factors affecting MDS, followed by the relative humidity (RH), while air temperature (Ta) and wind velocity had the least effect. A good linear relationship was founded (r2 = 0.921) between MDS and environmental variables (Rs, VPD, RH, and θv), which can be used to establish a reference value for detecting plant water stress based on the MDS patterns.

  8. Effects of Diameter on Initial Stiffness of P-Y Curves for Large-Diameter Piles in Sand

    DEFF Research Database (Denmark)

    Sørensen, Søren Peder Hyldal; Ibsen, Lars Bo; Augustesen, Anders Hust

    2010-01-01

    For offshore wind turbines, monopile foundations with diameters of 4–6m are often employed. The Winkler model approach, where the soil resistance is modelled as uncoupled springs with spring stiffness’ given by p-y curves, is traditionally employed for the design of monopiles. However, this metho...... analyses by means of the commercial program FLAC3D incorporating a Mohr-Coulomb failure criterion. The numerical model is validated with laboratory tests in a pressure tank at Aalborg University....

  9. Core bulk of wool fibres as a function of their curvature and diameter

    Energy Technology Data Exchange (ETDEWEB)

    Kozyreff, G.; Wake, G.; Ockendon, H.; Sumner, R.M.W

    2003-08-11

    The compressibility of a fibre mass affects processing and end-product performance. The compressibility of wool can be measured by compressing a sample of clean fibre in a cylinder with a standard weight. The specific volume of the sample after compression is termed its bulk, or core bulk if a short core bored sample is used. Prediction of core bulk from the standard simultaneous measures of fibre diameter and fibre curvature would reduce testing costs. This applies to all types of fibre assemblies, but the potential for highest industrial influence is with natural fibres (wool, hairs, etc.) as the key characteristic of bulk is controlled by relatively few genes, and the ability is available to increase the bulkiness of a fibre from animals by carefully selective breeding procedures. A first approach to the problem is to model the wool sample as a collection of flexible rings. The Euler strut equation is then used to describe the rings and compute their linear deformation in response to the applied load. The resulting formula reveals that the core bulk depends on the fibre diameter and the fibre curvature only through their product. This agrees with an expression for the core bulk derived from van Wyk's formula (van Wyk, 1946) in one limit.

  10. Understanding effective diameter and its application to terrestrial radiation in ice clouds

    Science.gov (United States)

    Mitchell, D. L.; Lawson, R. P.; Baker, B.

    2011-04-01

    The cloud property known as "effective diameter" or "effective radius", which in essence is the cloud particle size distribution (PSD) volume at bulk density divided by its projected area, is used extensively in atmospheric radiation transfer, climate modeling and remote sensing. This derives from the assumption that PSD optical properties can be uniquely described in terms of their effective diameter, De, and their cloud water content (CWC), henceforth referred to as the De-CWC assumption. This study challenges this assumption, showing that while the De-CWC assumption appears generally valid for liquid water clouds, it appears less valid for ice clouds in regions where (1) absorption is not primarily a function of either the PSD ice water content (IWC) or the PSD projected area, and (2) where wave resonance (i.e. photon tunneling) contributes significantly to absorption. These two regions often strongly coincide at terrestrial wavelengths when DeMADA), a physical understanding of the limitations of the De-IWC assumption was made possible by using MADA. MADA allows one to approximate the contribution of photon tunneling to absorption relative to other optical processes, which reveals that part of the error regarding the De-IWC assumption can be associated with tunneling. By relating the remaining error to the radiation penetration depth in bulk ice (ΔL) due to absorption, the domain where the De-IWC assumption is weakest was described in terms of De and ΔL.

  11. A curved-grid gas proportional scintillation counter instrumented with a 25-mm active-diameter photosensor

    Energy Technology Data Exchange (ETDEWEB)

    Monteiro, C.M.B.; Morgado, R.E.; Santos, J.M.F. dos E-mail: jmf@gian.fis.uc.pt; Conde, C.A.N

    2004-04-21

    The curved-grid technique provides a simple method to compensate for the variation in solid angle viewed by the PMT in large-area gas proportional scintillation counters (GPSC), improving their performance. The scintillation region is delimited by a planar grid and a curved one, whose shape is calculated to produce a radially increasing scintillation yield, compensating for the decrease in the solid angle. In this work, we applied this technique to a GPSC instrumented with a PMT having a 25-mm diameter photocathode. The maximum ratio of the detector entrance window to the photocathode diameter thus far achieved, without significant performance degradation, is 1.

  12. Influence of Changing the Diameter of the Bubble Generator Bottle and Expiratory Limb on Bubble CPAP: An in vitro Study

    Directory of Open Access Journals (Sweden)

    Chun-Shan Wu

    2012-12-01

    Conclusion: The size and submergence depth of an expiratory limb of a CPAP circuit, the diameter of the bubble generator bottle, and the compliance of the model lung all influence the magnitude and frequency of the transmitted pressure waveform. Therefore, these factors may affect lung volume recruitment and breathing efficiency in bubble CPAP.

  13. Woodland: dynamics of average diameters of coniferous tree stands of the principal forest types

    Directory of Open Access Journals (Sweden)

    R. A. Ziganshin

    2016-08-01

    Full Text Available The analysis of age dynamics of average diameters of deciduous tree stands of different forest types at Highland Khamar-Daban (natural woodland in South-East Baikal Lake region has been done. The aggregate data of average tree, the analysis of age dynamics of average diameters of a deciduous tree stands of stand diameters by age classes, as well as tree stand current periodic and overall average increment are presented and discussed in the paper. Forest management appraisal is done. The most representative forest types have been selected to be analyzed. There were nine of them including three Siberian stone pine Pinus sibirica Du Tour stands, three Siberian fir Abies sibirica Ledeb. stands, one Siberian spruce Picea obovata Ledeb. stand, and two dwarf Siberian pine Pinus pumila (Pallas Regel stands. The whole high-altitude range of mountain taiga has been evaluated. Mathematical and statistic indicators have been calculated for every forest type. Stone pine stands are the largest. Dynamics of mean diameters of forest stands have been examined by dominant species for every forest type. Quite a number of interesting facts have been elicited. Generally, all species have maximal values of periodic annual increment that is typical for young stands, but further decrease of increment is going on differently and connects to the different lifetime of wood species. It is curious that annual increment of the dwarf Siberian pine stands almost does not decrease with aging. As for mean annual increment, it is more stable than periodic annual increment. From the fifth age class (age of stand approaching maturity mean annual increment of cedar stands varies from 0.20 to 0.24 cm per year; from 0.12–0.15 to 0.18–0.21 cm per year – in fir stands; from 0.18 to 0.24 cm per year – in spruce stands; and from 0.02–0.03 to 0.05–0.06 cm per year – in draft pine stands. Mean annual increment of dwarf Siberian pine increases with aging and increment of other

  14. Piston diameter in stapes surgery. Does it have a bearing?

    Directory of Open Access Journals (Sweden)

    Neha Gupta

    2014-01-01

    Full Text Available Aims and Objectives: This prospective randomized controlled trial was done to study the effect of piston diameter on hearing outcomes after stapedotomy. Materials and Methods: All the patients diagnosed to have otosclerosis were included in the study. A total of 52 patients were studied ranging in age from 18 to 50 years. The subjects were randomized into two groups, that is, 0.4 mm piston (group A and 0.6 mm piston (group B. The subjects were taken up for small fenestra stapedotomy using either a 0.4 or 0.6 mm piston. The main outcome measures were hearing improvement, air-bone gap closure, and overclosure of air-bone gap. Results: There was no statistical difference in hearing improvement in two different piston diameters, 0.4 and 0.6 mm at speech frequencies. In group A, the air-bone gap improvement in the third follow-up was not significant (P > 0.05, whereas group B showed a statistically significant improvement (P = 0.003. The mean overclosure of air-bone gap was better in patients with 0.4 mm piston at speech frequencies and also at 250 Hz. Significantly, overclosure of air-bone gap at higher frequencies (4 and 8 KHz was seen only with a smaller sized piston. (0.4 mm. Discussion: We analyzed the effect of piston diameter on the hearing results after small fenestra stapedotomy by using similar surgical procedure and similar prosthesis in all patients. Conclusion: There is evidence to suggest that 0.4 mm piston may be better suited for providing optimum hearing results.

  15. A solar cycle lengthwise series of solar diameter measurements

    Science.gov (United States)

    Penna, J. L.; Andrei, A. H.; Boscardin, S. C.; Neto, E. Reis; d'Ávila, V. A.

    2010-02-01

    The measurements of the solar photospheric diameter rank among the most difficult astronomic observations. Reasons for this are the fuzzy definition of the limb, the SNR excess, and the adverse daytime seeing condition. As a consequence there are very few lengthy and consistent time series of such measurements. Using modern techniques, just the series from the IAG/USP and from Calern/OCA span more than one solar cycle. The Rio de Janeiro Group observations started in 1997, and therefore in 2008 one complete solar cycle time span can be analyzed. The series shares common principles of observation and analysis with the ones afore mentioned, and it is complementary on time to them. The distinctive features are the larger number of individual points and the improved precision. The series contains about 25,000 single observations, evenly distributed on a day-by-day basis. The typical error of a single observation is half an arc-second, enabling us to investigate variations at the expected level of tens of arc-second on a weekly basis. These features prompted to develop a new methodology for the investigation of the heliophysical scenarios leading to the observed variations, both on time and on heliolatitude. The algorithms rely on running averages and time shifts to derive the correlation and statistical incertitude for the comparison of the long term and major episodes variations of the solar diameter against activity markers. The results bring support to the correlation between the diameter variation and the solar activity, but evidentiating two different regimens for the long term trend and the major solar events.

  16. Renormalized Volume

    CERN Document Server

    Gover, A Rod

    2016-01-01

    For any conformally compact manifold with hypersurface boundary we define a canonical renormalized volume functional and compute an explicit, holographic formula for the corresponding anomaly. For the special case of asymptotically Einstein manifolds, our method recovers the known results. The anomaly does not depend on any particular choice of regulator, but the coefficients of divergences do. We give explicit formulae for these divergences valid for any choice of regulating hypersurface; these should be relevant to recent studies of quantum corrections to entanglement entropies. The anomaly is expressed as a conformally invariant integral of a local Q-curvature that generalizes the Branson Q-curvature by including data of the embedding. In each dimension this canonically defines a higher dimensional generalization of the Willmore energy/rigid string action. We show that the variation of these energy functionals is exactly the obstruction to solving a singular Yamabe type problem with boundary data along the...

  17. Mesiodistal crown diameters of permanent dentition in schoolchildren from Lima

    OpenAIRE

    Pineda-Mejia, Martha; Departamento Académico de Estomatología Rehabilitadora, Facultad Odontología de la Universidad Nacional Mayor de San Marco, Perú.; Petkova- Gueorguieva, Marieta; Facultad Odontología de la Universidad Nacional Mayor de San Marcos.

    2015-01-01

    The purpose of this study was to determine the size of mesiodistal diameters of permanent teeth in a school population of the city of Lima, to analyze the differences between homologous teeth, sexual dimorphism of permanent teeth as well as the degree of variability of the measurements. Methodology: The study was conducted on 400 students of mestizos (200 men and 200 women) 10 to 12 years, from three schools in the districts of la Victoria and Barrios Altos, Lima city. The procedure was perfo...

  18. Economic strategies of plant absorptive roots vary with root diameter

    Science.gov (United States)

    Kong, D. L.; Wang, J. J.; Kardol, P.; Wu, H. F.; Zeng, H.; Deng, X. B.; Deng, Y.

    2016-01-01

    Plant roots typically vary along a dominant ecological axis, the root economics spectrum, depicting a tradeoff between resource acquisition and conservation. For absorptive roots, which are mainly responsible for resource acquisition, we hypothesized that root economic strategies differ with increasing root diameter. To test this hypothesis, we used seven plant species (a fern, a conifer, and five angiosperms from south China) for which we separated absorptive roots into two categories: thin roots (thickness of root cortex plus epidermis perspective on our understanding of the root economics spectrum.

  19. On the Connectedness and Diameter of a Geometric Johnson Graph

    CERN Document Server

    Bautista-Santiago, Crevel; Fabila-Monroy, Ruy; Flores-Peñaloza, David; González-Aguilar, Hernán; Lara, Dolores; Sarmiento, Eliseo; Urrutia, Jorge

    2012-01-01

    Let $P$ be a set of $n$ points in general position in the plane. A subset $I$ of $P$ is called an \\emph{island} if there exists a convex set $C$ such that $I = P \\cap C$. In this paper we define the \\emph{generalized island Johnson graph} of $P$ as the graph whose vertex consists of all islands of $P$ of cardinality $k$, two of which are adjacent if their intersection consists of exactly $l$ elements. We show that for large enough values of $n$, this graph is connected, and give upper and lower bounds on its diameter.

  20. A Study of Spiral Tap with Large Diameter

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The design and manufacture of spiral tap yet are in r esearch stage at present. This paper mainly introduces how to calculate its geom etric parameters and scientific selection of them with vector method. In additio n, an empiric formula of the tool life of spiral tap with large diameter is esta blished by method of correlation. The practice of design, manufacture and applying proves the advantage of spiral tap by the comparison between the spiral tap and common tap with same size. In the application of...

  1. Impact damage in small diameter graphite/epoxy composite struts

    Science.gov (United States)

    Chen, G.-S.; Bidinger, G. M.; Cho, S.; Lou, M. C.

    1992-01-01

    An investigation was performed to study impact induced damage in small-diameter struts made of a composite material with a brittle matrix system. The major focus is on characterizing the impact behavior associated with the barely visible damage. An experimental procedure including ultrasonic inspection, instrumented impact testing, and delamination buckling and residual strength measurements is presented. From the ultrasonic inspection, it is found that for the strut specimens under investigation, the impact energy level for barely visible damage threshold is above that of the internal damage threshold. A 60- to 65-percent reduction in compressive strength was typical for struts subjected to the barely visible impact damage threshold.

  2. Twist Neutrality and the Diameter of the Nucleosome Core Particle

    DEFF Research Database (Denmark)

    Bohr, Jakob; Olsen, Kasper

    2012-01-01

    The diameter of the nucleosome core particle is the same for all the eukaryotes. Here we discuss the possibility that this selectiveness is consistent with a propensity for twist neutrality, in particular, for the double helical DNA to stay rotationally neutral when strained. Reorganization of DNA...... cannot be done without some level of temporal tensile stress, and as a consequence chiral molecules, such as helices, will twist under strain. The requirement that the nucleosome, constituting the nucleosome core particle and linker DNA, has a vanishing strain-twist coupling leads to a requirement...

  3. Aharonov—Bohm Oscillations in Small Diameter Bi Nanowires

    Science.gov (United States)

    Konopko, L.

    The Aharonov-Bohm effect (AB) exists in cylindrical wires as the magnetoresistance (MR) oscillations with a period ΔB that is proportional to Φ0 / S, where Φ0 = h / e is the flux quantum and S is the wire cross section. The AB-type longitudinal MR oscillations with period ΔB = Φ0 / S caused by electrons undergoing continuous grazing incidence at the wire wall have been observed previously at 4.2 K in single bismuth nanowires with a diameter 0. 2 Spivak theory.

  4. Note: Computer controlled rotation mount for large diameter optics

    CERN Document Server

    Rakonjac, Ana; Deb, Amita B; Kjærgaard, Niels

    2012-01-01

    We describe the construction of a motorized optical rotation mount with a 40 mm clear aperture. The device is used to remotely control the power of large diameter laser beams for a magneto-optical trap (MOT). A piezo-electric ultrasonic motor on a printed circuit board (PCB) provides rotation with a precision better than 0.03 deg and allows for a very compact design. The rotation unit is controlled from a computer via serial communication, making integration into most software control platforms straightforward.

  5. Influence of filament diameter on superconducting properties of MgB2 multi-core wires

    Science.gov (United States)

    Reissner, M.; Bulla, L.; Husek, I.; Melišek, T.; Kováč, P.

    2013-06-01

    Magnetic behaviour of a series of MgB2 wires, in each case with 19 filaments of superconductor, surrounded by Ti as barrier and reinforced by stainless steel, prepared in the same way but mechanically deformed to different filament diameters ϕ between 58.5 and 17.7 µm, was investigated. Whereas no influence of ϕ on superconducting transition temperature is found, the width of the transition increases with ϕ. Critical current density, irreversibility line and mean effective activation energy U decrease systematically with decreasing ϕ. From a comparison of the field dependence of the pinning force and the temperature dependence of U, it is concluded, that pinning is dominated at low fields by grain boundary pinning and at higher fields by point defect pinning, with a rather broad distribution of pinning energies.

  6. Dynamic arterial elastance predicts mean arterial pressure decrease associated with decreasing norepinephrine dosage in septic shock.

    Science.gov (United States)

    Guinot, Pierre-Grégoire; Bernard, Eugénie; Levrard, Mélanie; Dupont, Hervé; Lorne, Emmanuel

    2015-01-19

    Gradual reduction of the dosage of norepinephrine (NE) in patients with septic shock is usually left to the physician's discretion. No hemodynamic indicator predictive of the possibility of decreasing the NE dosage is currently available at the bedside. The respiratory pulse pressure variation/respiratory stroke volume variation (dynamic arterial elastance (Eadyn)) ratio has been proposed as an indicator of vascular tone. The purpose of this study was to determine whether Eadyn can be used to predict the decrease in arterial pressure when decreasing the NE dosage in resuscitated sepsis patients. A prospective study was carried out in a university hospital intensive care unit. All consecutive patients with septic shock monitored by PICCO2 for whom the intensive care physician planned to decrease the NE dosage were enrolled. Measurements of hemodynamic and PICCO2 variables were obtained before/after decreasing the NE dosage. Responders were defined by a >15% decrease in mean arterial pressure (MAP). In total, 35 patients were included. MAP decreased by >15% after decreasing the NE dosage in 37% of patients (n = 13). Clinical characteristics appeared to be similar between responders and nonresponders. Eadyn was lower in responders than in nonresponders (0.75 (0.69 to 0.85) versus 1 (0. 83 to 1.22), P decrease in arterial pressure, with an area under the receiver-operating characteristic curve of 0.87 (95% confidence interval (95% CI): 0.72 to 0.96; P decrease in arterial pressure in response to NE dose reduction. Eadyn may constitute an easy-to-use functional approach to arterial-tone assessment, which may be helpful to identify patients likely to benefit from NE dose reduction.

  7. Comparison of pupil diameter and tear production in dogs treated with acepromazine, tramadol and their combination

    Directory of Open Access Journals (Sweden)

    Paulo Henrique de Albuquerque Santos

    2013-04-01

    Full Text Available Some ophthalmic surgeries require induction of mydriasis, however, drugs traditionally used for this purpose significantly reduces tear production. To evaluate the effect of acepromazine and tramadol, used alone or in combination, on pupil diameter, tear production, heart and respiratory rate, systolic blood pressure and rectal temperature, these drugs were administered to seven clinically normal dogs divided into three experimental groups (G1 - acepromazine; G2 - tramadol; G3 - tramadol + acepromazine that differed only in the sedation protocol. Parameters were measured in four experimental moments. Miosis occurred in G1, in addition to reduced tear production and respiratory rate. No significant changes were found in the parameters assessed in G2, whereas in G3, there was decrease in tear production of the right eye, decrease in the respiratory rate and rectal temperature. Tramadol proved to be a drug suitable for pre-anesthetic procedures that require the maintenance of pupil diameter and keeps the tear production within normal parameters. However, the use of acepromazine alone or in combination with tramadol requires protection of the patient's eye surface to prevent the occurrence of undesirable ophthalmic changes.

  8. Single Si nanowire (diameter ≤ 100 nm) based polarization sensitive near-infrared photodetector with ultra-high responsivity.

    Science.gov (United States)

    Das, K; Mukherjee, S; Manna, S; Ray, S K; Raychaudhuri, A K

    2014-10-01

    We report the fabrication and optical response of boron-doped single silicon nanowire-based metal-semiconductor-metal photodetector. Typical single nanowire devices with diameter of ∼80-100 nm and electrode spacing of ∼1 μm were made using electron-beam lithography from nanowires, grown by a metal-assisted chemical etching process. A high responsivity, of the order of 10(4) A W(-1), was observed even at zero bias in a single nanowire photodetector with peak responsivity in the near-infrared region. The responsivity was found to increase with increasing bias and decreasing nanowire diameter. Finite element based optical simulation was proposed to explain the diameter dependent performance of a single nanowire. The observed photoresponse is sensitive to the polarization of exciting light source, allowing the device to act as a polarization-dependent near-infrared photodetector.

  9. Study on Diameter Controlled Growth of Carbon Nanotubes by LaAl1-xFexO3 Catalysts

    Institute of Scientific and Technical Information of China (English)

    PENG Feng; WANG Hong-juan

    2005-01-01

    A series of LaAl1-xFexO3 catalysts prepared with lanthanum nitrate, aluminium nitrate and iron nitrate was investigated in catalytical syntheses of carbon nanotubes with high yields and purity. The properties of carbon nanotubes prepared by the method of CVD(chemical vapor deposition) with n-hexane as the carbon resource were studied and it was shown that the diameter of carbon nanotubes can be controlled by the molar ratio of iron to aluminum in the catalysts and that the diameter of carbon nanotubes changes a little with the decrease of the iron content in the catalysts. From the TEM pictures of carbon nanotubes, it can be found that the LaAl1-xFexO3 catalysts have a significant influence on the wall thickness of the carbon nanotubes, whereas they have little influence on the inner diameter of the carbon nanotubes.

  10. Multiple Small Diameter Drillings Increase Femoral Neck Stability Compared with Single Large Diameter Femoral Head Core Decompression Technique for Avascular Necrosis of the Femoral Head.

    Science.gov (United States)

    Brown, Philip J; Mannava, Sandeep; Seyler, Thorsten M; Plate, Johannes F; Van Sikes, Charles; Stitzel, Joel D; Lang, Jason E

    2016-10-26

    Femoral head core decompression is an efficacious joint-preserving procedure for treatment of early stage avascular necrosis. However, postoperative fractures have been described which may be related to the decompression technique used. Femoral head decompressions were performed on 12 matched human cadaveric femora comparing large 8mm single bore versus multiple 3mm small drilling techniques. Ultimate failure strength of the femora was tested using a servo-hydraulic material testing system. Ultimate load to failure was compared between the different decompression techniques using two paired ANCOVA linear regression models. Prior to biomechanical testing and after the intervention, volumetric bone mineral density was determined using quantitative computed tomography to account for variation between cadaveric samples and to assess the amount of bone disruption by the core decompression. Core decompression, using the small diameter bore and multiple drilling technique, withstood significantly greater load prior to failure compared with the single large bore technique after adjustment for bone mineral density (pcore decompression techniques. When considering core decompression for the treatment of early stage avascular necrosis, the multiple small bore technique removed less bone volume, thereby potentially leading to higher load to failure.

  11. Mechanisms responsible for decreased glomerular filtration in hibernation and hypothermia

    Science.gov (United States)

    Tempel, G. E.; Musacchia, X. J.; Jones, S. B.

    1977-01-01

    Measurements of blood pressure, heart rate, red blood cell and plasma volumes, and relative distribution of cardiac output were made on hibernating and hypothermic adult male and female golden hamsters weighing 120-140 g to study the mechanisms underlying the elimination or marked depression of renal function in hibernation and hypothermia. The results suggest that the elimination or marked depression in renal function reported in hibernation and hypothermia may partly be explained by alterations in cardiovascular system function. Renal perfusion pressure which decreases nearly 60% in both hibernation and hypothermia and a decrease in plasma volume of roughly 35% in the hypothermic animal might both be expected to markedly alter glomerular function.

  12. STUDY ON RECIPROCATING SEALS FOR A LARGER DIAMETER AXIAL PISTON

    Institute of Scientific and Technical Information of China (English)

    Yang Jian; Yang Huayong; Xu Bing

    2004-01-01

    Sealing performance of the reciprocating seals on a larger diameter (100 mm in diameter ) axial piston is theoretically investigated.Based on the characteristics of the clearance flow between the seal and the piston, reasonable boundary conditions for Navier-Stokes equations are determined and the equations are modified, so that the final equations can describe the real flow state of the clearance flow.Through combining the final equations with finite element method, the pressure distributions within the clearance field during the reciprocating motion of the piston and the leakage rate with the pressure are studied.The deflections of the seal which affect sealing performance are calculated as well.Sealing performance of piston seals using oil as the working liquid is compared with using water.It is concluded that the seal using water as the working liquid is under dry friction, which cannot be dealt with the theory of fluid mechanics.The seal structure is only acceptable using oil as the working liquid..

  13. Measuring angular diameter distances of strong gravitational lenses

    CERN Document Server

    Jee, Inh; Suyu, Sherry H

    2014-01-01

    The distance-redshift relation plays a fundamental role in constraining cosmological models. In this paper, we show that measurements of positions and time delays of strongly lensed images of a background galaxy, as well as those of the velocity dispersion and mass profile of a lens galaxy, can be combined to extract the angular diameter distance of the lens galaxy. Physically, as the velocity dispersion and the time delay give a gravitational potential ($GM/r$) and a mass ($GM$) of the lens, respectively, dividing them gives a physical size ($r$) of the lens. Comparing the physical size with the image positions of a lensed galaxy gives the angular diameter distance to the lens. A mismatch between the exact locations at which these measurements are made can be corrected by measuring a local slope of the mass profile. We expand on the original idea put forward by Paraficz and Hjorth, who analyzed singular isothermal lenses, by allowing for an arbitrary slope of a power-law spherical mass density profile, an ex...

  14. The Use of Narrow Diameter Implants in the Molar Area

    Directory of Open Access Journals (Sweden)

    M. Saad

    2016-01-01

    Full Text Available Implant rehabilitations in the posterior jaw are influenced by many factors such as the condition of the remaining teeth, the force factors related to the patient, the quality of the bone, the maintenance of the hygiene, the limited bone height, the type and extent of edentulism, and the nature of the opposing arch. The gold standard is to place a regular diameter implant (>3.7 mm or a wide one to replace every missing molar. Unfortunately, due to horizontal bone resorption, this option is not possible without lateral bone augmentation. In this situation, narrow diameter implant (NDI < 3.5 mm could be the alternative to lateral bone augmentation procedures. This paper presents a clinical study where NDIs were used for the replacement of missing molars. They were followed up to 11 years. Special considerations were observed and many parameters were evaluated. NDI could be used to replace missing molar in case of moderate horizontal bone resorption if strict guidelines are respected. Yet, future controlled prospective clinical trials are required to admit their use as scientific evidence.

  15. Tunable engineered skin mechanics via coaxial electrospun fiber core diameter.

    Science.gov (United States)

    Blackstone, Britani Nicole; Drexler, Jason William; Powell, Heather Megan

    2014-10-01

    Autologous engineered skin (ES) offers promise as a treatment for massive full thickness burns. Unfortunately, ES is orders of magnitude weaker than normal human skin causing it to be difficult to apply surgically and subject to damage by mechanical shear in the early phases of engraftment. In addition, no manufacturing strategy has been developed to tune ES biomechanics to approximate the native biomechanics at different anatomic locations. To enhance and tune ES biomechanics, a coaxial (CoA) electrospun scaffold platform was developed from polycaprolactone (PCL, core) and gelatin (shell). The ability of the coaxial fiber core diameter to control both scaffold and tissue mechanics was investigated along with the ability of the gelatin shell to facilitate cell adhesion and skin development compared to pure gelatin, pure PCL, and a gelatin-PCL blended fiber scaffold. CoA ES exhibited increased cellular adhesion and metabolism versus PCL alone or gelatin-PCL blend and promoted the development of well stratified skin with a dense dermal layer and a differentiated epidermal layer. Biomechanics of the scaffold and ES scaled linearly with core diameter suggesting that this scaffold platform could be utilized to tailor ES mechanics for their intended grafting site and reduce graft damage in vitro and in vivo.

  16. Diameter of titanium nanotubes influences anti-bacterial efficacy

    Energy Technology Data Exchange (ETDEWEB)

    Ercan, Batur; Taylor, Erik; Webster, Thomas J [School of Engineering, Brown University, Providence, RI 02917 (United States); Alpaslan, Ece, E-mail: thomas_webster@brown.edu [Faculty of Engineering and Natural Sciences, Sabanci University, Istanbul (Turkey)

    2011-07-22

    Bacterial infection of in-dwelling medical devices is a growing problem that cannot be treated by traditional antibiotics due to the increasing prevalence of antimicrobial resistance and biofilm formation. Here, due to changes in surface parameters, it is proposed that bacterial adhesion can be prevented through nanosurface modifications of the medical device alone. Toward this goal, titanium was created to possess nanotubular surface topographies of highly controlled diameters of 20, 40, 60, or 80 nm, sometimes followed by heat treatment to control chemistry and crystallinity, through a novel anodization process. For the first time it was found that through the control of Ti surface parameters including chemistry, crystallinity, nanotube size, and hydrophilicity, significantly changed responses of both Staphylococcus epidermidis and Staphylococcus aureus (pathogens relevant for orthopaedic and other medical device related infections) were measured. Specifically, heat treatment of 80 nm diameter titanium tubes produced the most robust antimicrobial effect of all surface treatment parameters tested. This study provides the first step toward understanding the surface properties of nano-structured titanium that improve tissue growth (as has been previously observed with nanotubular titanium), while simultaneously reducing infection without the use of pharmaceutical drugs.

  17. Algorithms for the extraction of various diameter vessels.

    Science.gov (United States)

    Tremblais, B; Capelle-Laize, A S; Augereau, B

    2007-01-01

    In this communication we propose a new and automatic strategy for the multi-scale extraction of vessels. The objective is to obtain a good representation of the vessels. That is to say a precise characterization of their centerlines and diameters. The adopted solution requires the generation of an image scale-space in which the various levels of details allow to process arteries of any diameter. The proposed method is implemented using the Partial Differential Equations (PDE) and differential geometry formalisms. The differential geometry allows, by the computation of a new valley response, to characterize the centerlines of vessels as well as the bottom lines of the valleys of the image surface. The information given by the centerlines and valley response at different scales are used to obtain the 2D multi-scale centerlines of the arteries. To that purpose, we construct a multi-scale adjacency graph which permits to keep the K strongest detections. Then, the detection we obtain is coded as an attributed graph. The suggested algorithm is applied in the scope of two kinds of angiograms: coronaries and retinal angiograms.

  18. Stellar Diameters and Temperatures II. Main Sequence K & M Stars

    CERN Document Server

    Boyajian, Tabetha S; van Belle, Gerard; McAlister, Harold A; Brummelaar, Theo A ten; Kane, Stephen R; Muirhead, Phil; Jones, Jeremy; White, Russel; Schaefer, Gail; Ciardi, David; Henry, Todd; López-Morales, Mercedes; Ridgway, Stephen; Gies, Douglas; Jao, Wei-Chun; Rojas-Ayala, Bárbara; Parks, J Robert; Sturmann, Laszlo; Sturmann, Judit; Turner, Nils H; Farrington, Chris; Goldfinger, P J; Berger, David H

    2012-01-01

    We present interferometric diameter measurements of 21 K- and M- dwarfs made with the CHARA Array. This sample is enhanced by literature radii measurements to form a data set of 33 K-M dwarfs with diameters measured to better than 5%. For all 33 stars, we compute absolute luminosities, linear radii, and effective temperatures (Teff). We develop empirical relations for \\simK0 to M4 main- sequence stars between the stellar Teff, radius, and luminosity to broad-band color indices and metallicity. These relations are valid for metallicities between [Fe/H] = -0.5 and +0.1 dex, and are accurate to \\sim2%, \\sim5%, and \\sim4% for Teff, radius, and luminosity, respectively. Our results show that it is necessary to use metallicity dependent transformations to convert colors into stellar Teff's, radii, and luminosities. We find no sensitivity to metallicity on relations between global stellar properties, e.g., TEFF-radius and TEFF-luminosity. Robust examinations of single star TEFF's and radii compared to evolutionary m...

  19. COMPLICATIONS RELATED TO GASTRIC BYPASS PERFORMED WITH DIFFERENT GASTROJEJUNAL DIAMETERS

    Science.gov (United States)

    SAMPAIO-NETO, José; BRANCO-FILHO, Alcides José; NASSIF, Luis Sérgio; BROSKA, Anne Caroline; KAMEI, Douglas Jun; NASSIF, André Thá

    2016-01-01

    ABSTRACT Background: Among the options for surgical treatment of obesity, the most widely used has been the Roux-en-Y gastric bypass. The gastrojejunal anastomosis can be accomplished in two ways: handsewn or using circular and linear stapled. The complications can be divided in early and late. Aim: To compare the incidence of early complications related with the handsewn gastrojejunal anastomosis in gastric bypass using Fouchet catheter with different diameters. Method: The records of 732 consecutive patients who had undergone the bypass were retrospectively analyzed and divided in two groups, group 1 with 12 mm anastomosis (n=374), and group 2 with 15 mm (n=358). Results: The groups showed anastomotic stenosis with rates of 11% and 3.1% respectively, with p=0.05. Other variables related to the anastomosis were also analyzed, but without statistical significance (p>0.05). Conclusion: The diameter of the anastomosis of 15 mm was related with lower incidence of stenosis. It was found that these patients had major bleeding postoperatively and lower surgical site infection, and in none was observed presence of anastomotic leak. PMID:27683767

  20. Confined-Volume Effect on the Thermal Properties of Encapsulated Phase Change Materials for Thermal Energy Storage.

    Science.gov (United States)

    De Castro, Paula F; Ahmed, Adham; Shchukin, Dmitry G

    2016-03-18

    We have encapsulated the heat exchange material, n-docosane, into polyurethane capsules of different sizes. Decreasing the size of the capsules leads to changes of the crystallinity of phase-change material as well as melting/crystallization temperature. The novelty of the paper includes 1) protection of the nanostructured energy-enriched materials against environment during storage and controlled release of the encapsulated energy on demand and 2) study of the structure and surface-to-volume properties of the energy-enriched materials dispersed in capsules of different sizes. The stability of energy nanomaterials, influence of capsule diameter on their energy capacity, homogeneity and operation lifetime are investigated.

  1. Height-diameter allometry and above ground biomass in tropical montane forests: Insights from the Albertine Rift in Africa

    Science.gov (United States)

    Boyemba, Faustin; Lewis, Simon; Nabahungu, Nsharwasi Léon; Calders, Kim; Zapfack, Louis; Riera, Bernard; Balegamire, Clarisse; Cuni-Sanchez, Aida

    2017-01-01

    Tropical montane forests provide an important natural laboratory to test ecological theory. While it is well-known that some aspects of forest structure change with altitude, little is known on the effects of altitude on above ground biomass (AGB), particularly with regard to changing height-diameter allometry. To address this we investigate (1) the effects of altitude on height-diameter allometry, (2) how different height-diameter allometric models affect above ground biomass estimates; and (3) how other forest structural, taxonomic and environmental attributes affect above ground biomass using 30 permanent sample plots (1-ha; all trees ≥ 10 cm diameter measured) established between 1250 and 2600 m asl in Kahuzi Biega National Park in eastern Democratic Republic of Congo. Forest structure and species composition differed with increasing altitude, with four forest types identified. Different height-diameter allometric models performed better with the different forest types, as trees got smaller with increasing altitude. Above ground biomass ranged from 168 to 290 Mg ha-1, but there were no significant differences in AGB between forests types, as tree size decreased but stem density increased with increasing altitude. Forest structure had greater effects on above ground biomass than forest diversity. Soil attributes (K and acidity, pH) also significantly affected above ground biomass. Results show how forest structural, taxonomic and environmental attributes affect above ground biomass in African tropical montane forests. They particularly highlight that the use of regional height-diameter models introduces significant biases in above ground biomass estimates, and that different height-diameter models might be preferred for different forest types, and these should be considered in future studies. PMID:28617841

  2. Height-diameter allometry and above ground biomass in tropical montane forests: Insights from the Albertine Rift in Africa.

    Science.gov (United States)

    Imani, Gérard; Boyemba, Faustin; Lewis, Simon; Nabahungu, Nsharwasi Léon; Calders, Kim; Zapfack, Louis; Riera, Bernard; Balegamire, Clarisse; Cuni-Sanchez, Aida

    2017-01-01

    Tropical montane forests provide an important natural laboratory to test ecological theory. While it is well-known that some aspects of forest structure change with altitude, little is known on the effects of altitude on above ground biomass (AGB), particularly with regard to changing height-diameter allometry. To address this we investigate (1) the effects of altitude on height-diameter allometry, (2) how different height-diameter allometric models affect above ground biomass estimates; and (3) how other forest structural, taxonomic and environmental attributes affect above ground biomass using 30 permanent sample plots (1-ha; all trees ≥ 10 cm diameter measured) established between 1250 and 2600 m asl in Kahuzi Biega National Park in eastern Democratic Republic of Congo. Forest structure and species composition differed with increasing altitude, with four forest types identified. Different height-diameter allometric models performed better with the different forest types, as trees got smaller with increasing altitude. Above ground biomass ranged from 168 to 290 Mg ha-1, but there were no significant differences in AGB between forests types, as tree size decreased but stem density increased with increasing altitude. Forest structure had greater effects on above ground biomass than forest diversity. Soil attributes (K and acidity, pH) also significantly affected above ground biomass. Results show how forest structural, taxonomic and environmental attributes affect above ground biomass in African tropical montane forests. They particularly highlight that the use of regional height-diameter models introduces significant biases in above ground biomass estimates, and that different height-diameter models might be preferred for different forest types, and these should be considered in future studies.

  3. Diameter distribution estimation with laser scanning based multisource single tree inventory

    Science.gov (United States)

    Kankare, Ville; Liang, Xinlian; Vastaranta, Mikko; Yu, Xiaowei; Holopainen, Markus; Hyyppä, Juha

    2015-10-01

    Tree detection and tree species recognition are bottlenecks of the airborne remote sensing-based single tree inventories. The effect of these factors in forest attribute estimation can be reduced if airborne measurements are aided with tree mapping information that is collected from the ground. The main objective here was to demonstrate the use of terrestrial laser scanning-derived (TLS) tree maps in aiding airborne laser scanning-based (ALS) single tree inventory (multisource single tree inventory, MS-STI) and its capability in predicting diameter distribution in various forest conditions. Automatic measurement of TLS point clouds provided the tree maps and the required reference information from the tree attributes. The study area was located in Evo, Finland, and the reference data was acquired from 27 different sample plots with varying forest conditions. The workflow of MS-STI included: (1) creation of automatic tree map from TLS point clouds, (2) automatic diameter at breast height (DBH) measurement from TLS point clouds, (3) individual tree detection (ITD) based on ALS, (4) matching the ITD segments to the field-measured reference, (5) ALS point cloud metric extraction from the single tree segments and (6) DBH estimation based on the derived metrics. MS-STI proved to be accurate and efficient method for DBH estimation and predicting diameter distribution. The overall accuracy (root mean squared error, RMSE) of the DBH was 36.9 mm. Results showed that the DBH accuracy decreased if the tree density (trees/ha) increased. The highest accuracies were found in old-growth forests (tree densities less than 500 stems/ha). MS-STI resulted in the best accuracies regarding Norway spruce (Picea abies (L.) H. Karst.)-dominated forests (RMSE of 29.9 mm). Diameter distributions were predicted with low error indices, thereby resulting in a good fit compared to the reference. Based on the results, diameter distribution estimation with MS-STI is highly dependent on the forest

  4. Development of a Modelling to Correlate Site and Diameter of Brain Metastases with Hippocampal Sparing Using Volumetric Modulated Arc Therapy

    Directory of Open Access Journals (Sweden)

    Silvia Chiesa

    2013-01-01

    Full Text Available Purpose. To correlate site and diameter of brain metastases with hippocampal sparing in patients treated by RapidArc (RA technique on whole brain with simultaneously integrated boost (SIB. Methods and Materials. An RA plan was calculated for brain metastases of 1-2-3 cm of diameter. The whole brain dose was 32.25 Gy (15 fractions, and SIB doses to brain metastases were 63 Gy (2 and 3 cm or 70.8 Gy (1 cm. Plans were optimized and evaluated for conformity, target coverage, prescription isodose to target volume, homogeneity index, and hippocampal sparing. Results. Fifteen brain lesions and RA plan were generated. Hippocampal volume was 4.09 cm3, and hippocampal avoidance volume was 17.50 cm3. Related to site of metastases, the mean hippocampal dose was 9.68 Gy2 for occipital lobe, 10.56 Gy2 for frontal lobe, 10.56 Gy2 for parietal lobe, 10.94 Gy2 for deep brain structures, and 40.44 Gy2 for temporal lobe. The mean hippocampal dose was 9.45 Gy2, 10.15 Gy2, and 11.70 Gy2 for diameter’s metastases of 1.2 and 3 cm, respectively, excluding results relative to temporal brain lesions. Conclusions. Location more than size of metastases can adversely influence the hippocampus sparing. Further investigation is necessary to meet definitive considerations.

  5. Decreasing luminescence lifetime of evaporating phosphorescent droplets

    Science.gov (United States)

    van der Voort, D. D.; Dam, N. J.; Sweep, A. M.; Kunnen, R. P. J.; van Heijst, G. J. F.; Clercx, H. J. H.; van de Water, W.

    2016-12-01

    Laser-induced phosphorescence has been used extensively to study spray dynamics. It is important to understand the influence of droplet evaporation in the interpretation of such measurements, as it increases luminescence quenching. By suspending a single evaporating n-heptane droplet in an acoustic levitator, the properties of lanthanide-complex europium-thenoyltrifluoroacetone-trioctylphosphine oxide (Eu-TTA-TOPO) phosphorescence are determined through high-speed imaging. A decrease was found in the measured phosphorescence decay coefficient (780 → 200 μs) with decreasing droplet volumes (10-9 → 10-11 m3) corresponding to increasing concentrations (10-4 → 10-2 M). This decrease continues up to the point of shell-formation at supersaturated concentrations. The diminished luminescence is shown not to be attributable to triplet-triplet annihilation, quenching between excited triplet-state molecules. Instead, the pure exponential decays found in the measurements show that a non-phosphorescent quencher, such as free TTA/TOPO, can be attributable to this decay. The concentration dependence of the phosphorescence lifetime can therefore be used as a diagnostic of evaporation in sprays.

  6. Influence of Electrospinning Parameters on Fiber Diameter and Mechanical Properties of Poly(3-Hydroxybutyrate (PHB and Polyanilines (PANI Blends

    Directory of Open Access Journals (Sweden)

    Ahmed M. El-hadi

    2016-03-01

    Full Text Available Random and oriented fibers of poly (3-hydroxybutyrate (PHB and their blends were manufactured using electrospinning using a co-solvent. The kind and the concentration of the co-solvent affected the diameter of electrospun fibers. The morphology, thermal analysis, and crystalline structure of electrospun fibers was studied using polarized optical microscop (POM, Differential scanning colametry (DSC, Scanning Electron Microscopy (SEM, Wide angle X-ray diffraction (WAXD, and FT-IR analysis. The diameter of the electrospun fibers decreases with increasing collector speed for the blends compared to pure PHB, which are about 6 µm in diameter. The fibers obtained from blends reduce to 2 µm. The aligned electrospun fiber mats obtained from pure PHB showed no signs of necking at different take-up speeds, but the blends show multiple necking. It was found by FT-IR that the peak intensity at 1379 cm−1 was lower by take up speed than in casting films; this peak is sensitive to crystallinity of PHB. The addition of polyanilines (PANIs to (PHB with a plasticizer decreases the diameter of the electrospun fiber.

  7. Pade interpolation by F-polynomials and transfinite diameter

    CERN Document Server

    Coman, Dan

    2011-01-01

    We define $F$-polynomials as linear combinations of dilations by some frequencies of an entire function $F$. In this paper we use Pade interpolation of holomorphic functions in the unit disk by $F$-polynomials to obtain explicitly approximating $F$-polynomials with sharp estimates on their coefficients. We show that when frequencies lie in a compact set $K\\subset\\mathbb C$ then optimal choices for the frequencies of interpolating polynomials are similar to Fekete points. Moreover, the minimal norms of the interpolating operators form a sequence whose rate of growth is determined by the transfinite diameter of $K$. In case of the Laplace transforms of measures on $K$, we show that the coefficients of interpolating polynomials stay bounded provided that the frequencies are Fekete points. Finally, we give a sufficient condition for measures on the unit circle which ensures that the sums of the absolute values of the coefficients of interpolating polynomials stay bounded.

  8. Lasering in a Waveguide with Scatterers in Diameter 20 nm

    Institute of Scientific and Technical Information of China (English)

    LIU Chun-Xu; LIU Jun-Ye; ZHANG Jia-Hua; DOU Kai

    2004-01-01

    We report random lasing achieved in a MEH-PPV/glass waveguide with the TiO2 scatterers in diameter 20nm that is significantly smaller than submicrometre of TiO2 scatterers in the films or suspensions previously reported on random lasing. The spectral lines are dramatically narrowed by almost two orders of magnitude compared with those excited by a xenon lamp. The amplified spontaneous emission is identified as the dominant mechanism in our system. Light localization might be achieved in a broad class of random materials based on the features of the mean free path l* = 5.4 × 105 nm, kl* > 1 and the Thouless number 6.73 × 10-5 with k being the wave number.

  9. Molecular transport through large-diameter DNA nanopores

    Science.gov (United States)

    Krishnan, Swati; Ziegler, Daniela; Arnaut, Vera; Martin, Thomas G.; Kapsner, Korbinian; Henneberg, Katharina; Bausch, Andreas R.; Dietz, Hendrik; Simmel, Friedrich C.

    2016-01-01

    DNA-based nanopores are synthetic biomolecular membrane pores, whose geometry and chemical functionality can be tuned using the tools of DNA nanotechnology, making them promising molecular devices for applications in single-molecule biosensing and synthetic biology. Here we introduce a large DNA membrane channel with an ≈4 nm diameter pore, which has stable electrical properties and spontaneously inserts into flat lipid bilayer membranes. Membrane incorporation is facilitated by a large number of hydrophobic functionalizations or, alternatively, streptavidin linkages between biotinylated channels and lipids. The channel displays an Ohmic conductance of ≈3 nS, consistent with its size, and allows electrically driven translocation of single-stranded and double-stranded DNA analytes. Using confocal microscopy and a dye influx assay, we demonstrate the spontaneous formation of membrane pores in giant unilamellar vesicles. Pores can be created both in an outside-in and an inside-out configuration. PMID:27658960

  10. Seismic fragility test of a 6-inch diameter pipe system

    Energy Technology Data Exchange (ETDEWEB)

    Chen, W. P.; Onesto, A. T.; DeVita, V.

    1987-02-01

    This report contains the test results and assessments of seismic fragility tests performed on a 6-inch diameter piping system. The test was funded by the US Nuclear Regulatory Commission (NRC) and conducted by ETEC. The objective of the test was to investigate the ability of a representative nuclear piping system to withstand high level dynamic seismic and other loadings. Levels of loadings achieved during seismic testing were 20 to 30 times larger than normal elastic design evaluations to ASME Level D limits would permit. Based on failure data obtained during seismic and other dynamic testing, it was concluded that nuclear piping systems are inherently able to withstand much larger dynamic seismic loadings than permitted by current design practice criteria or predicted by the probabilistic risk assessment (PRA) methods and several proposed nonlinear methods of failure analysis.

  11. Solar furnace satellite for large diameter crystal growth in space

    Science.gov (United States)

    Overfelt, Tony; Wells, Mark; Blake, John

    1993-02-01

    Investigators worldwide are preparing experiments to test the influence of low gravity found in space on the growth of many crystalline materials. However, power limitations prevent existing space crystal growth furnaces from being able to process samples any larger than about 2 cm, and in addition, the background microgravity levels found on the Space Shuttle are not low enough to significantly benefit samples much larger than 2 cm. This paper describes a novel concept of a free-flying platform utilizing well-established solar furnace technology to enable materials processing in space experiments on large-diameter crystals. The conceptual design of this Solar Furnace Satellite is described along with its operational scenario and the anticipated g levels.

  12. Molecular transport through large-diameter DNA nanopores

    Science.gov (United States)

    Krishnan, Swati; Ziegler, Daniela; Arnaut, Vera; Martin, Thomas G.; Kapsner, Korbinian; Henneberg, Katharina; Bausch, Andreas R.; Dietz, Hendrik; Simmel, Friedrich C.

    2016-09-01

    DNA-based nanopores are synthetic biomolecular membrane pores, whose geometry and chemical functionality can be tuned using the tools of DNA nanotechnology, making them promising molecular devices for applications in single-molecule biosensing and synthetic biology. Here we introduce a large DNA membrane channel with an ~4 nm diameter pore, which has stable electrical properties and spontaneously inserts into flat lipid bilayer membranes. Membrane incorporation is facilitated by a large number of hydrophobic functionalizations or, alternatively, streptavidin linkages between biotinylated channels and lipids. The channel displays an Ohmic conductance of ~3 nS, consistent with its size, and allows electrically driven translocation of single-stranded and double-stranded DNA analytes. Using confocal microscopy and a dye influx assay, we demonstrate the spontaneous formation of membrane pores in giant unilamellar vesicles. Pores can be created both in an outside-in and an inside-out configuration.

  13. Experiments with large diameter gravity driven impacting liquid jets

    Science.gov (United States)

    Storr, G. J.; Behnia, M.

    The phenomenon of a liquid jet released under gravity and falling through or impacting onto another liquid before colliding with an obstructing solid surface has been studied experimentally under isothermal conditions. Usually the jet diameter was sufficiently large to ensure jet coherency until collision. Direct flow visualization was used to study jets released into water pools with no air head space and jets impacting onto water pools after falling through an air head space. It is shown that distances predicting the onset of buoyancy and the entrainment of air using derivations from continuous plunging jets, are not applicable for impacting jets. The morphology of jet debris after collision with the solid surfaces correlates with the wetting properties of the jet liquid on the surface.

  14. NEOWISE diameters and albedos: now available on PDS!

    Science.gov (United States)

    Masiero, Joseph R.; Mainzer, Amy K.; Bauer, James M.; Cutri, Roc M.; Grav, Tommy; Kramer, Emily A.; Nugent, Carolyn; Sonnett, Sarah M.; Stevenson, Rachel; Wright, Edward L.

    2016-10-01

    We present the recent PDS release of minor planet physical property data from the WISE/NEOWISE fully cryogenic, 3-band cryo, and post-cryo surveys as well as the first year of the NEOWISE-Reactivation survey. This release includes 165,865 diameters, visible albedos, near-infrared albedos, and/or beaming parameters for 140,493 unique minor planets. The published data include near-Earth asteroids, Main Belt asteroids, Hildas, Jupiter Trojans, Centaurs, active Main Belt objects and irregular satellites of Jupiter and Saturn. We provide an overview of the available data and discuss the key features of the PDS data set. The data are available online at: http://sbn.psi.edu/pds/resource/neowisediam.html.

  15. CT dose equilibration and energy absorption in polyethylene cylinders with diameters from 6 to 55 cm

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xinhua; Zhang, Da; Liu, Bob, E-mail: bliu7@mgh.harvard.edu [Division of Diagnostic Imaging Physics and Webster Center for Advanced Research and Education in Radiation, Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts 02114 (United States)

    2015-06-15

    ratios changed with beam aperture and phantom axis but were insensitive to tube voltage. H(L) was insensitive to tube voltage and CT scanner model. As phantom diameter increased from 6 to 55 cm, E{sub in}/E generally decreased but asymptotically approached constant levels on the peripheral axes of large phantoms. The curve of E{sub in}/E versus scan length was almost identical to that of H(L). Similarly, E{sub out}/E increased with scan length and asymptotically approached the equilibrium for large scan lengths. E{sub out}/D{sub eq} was much less than the equilibrium length L{sub eq} where H(L) = 0.98, even with scan lengths much larger than L{sub eq}. Conclusions: The polyethylene phantom designed by ICRU Report No. 87 Committee and AAPM Task Group 200 is adequately long for assessing the midpoint dose and its equilibration in CT scanning. The short-to-long phantom dose ratios and the H(L) data provided in this paper allow easy evaluations of the midpoint dose, longitudinal dose distribution, and energy absorption in polyethylene phantoms. The results of dose equilibration and energy absorption presented herein may be insightful for the clinical CT scans with various subject sizes and scan lengths.

  16. Thoracic and abdominal aortic diameters in a general population: MRI-based reference values and association with age and cardiovascular risk factors

    Energy Technology Data Exchange (ETDEWEB)

    Mensel, Birger; Hesselbarth, Lydia; Wenzel, Michael; Kuehn, Jens-Peter; Hegenscheid, Katrin [University Medicine Greifswald, Institute of Diagnostic Radiology and Neuroradiology, Greifswald (Germany); Doerr, Marcus [University Medicine Greifswald, Department of Internal Medicine, Greifswald (Germany); DZHK (German Center for Cardiovascular Research), partner site Greifswald, Greifswald (Germany); Voelzke, Henry [University Medicine Greifswald, Institute for Community Medicine, Greifswald (Germany); DZHK (German Center for Cardiovascular Research), partner site Greifswald, Greifswald (Germany); Lieb, Wolfgang [Christian Albrechts University, Institute of Epidemiology, Kiel (Germany); Lorbeer, Roberto [Ludwig-Maximilians-University Hospital, Institute of Clinical Radiology, Munich (Germany)

    2016-04-15

    To generate reference values for thoracic and abdominal aortic diameters determined by magnetic resonance imaging (MRI) and analyse their association with cardiovascular risk factors in the general population. Data from participants (n = 1759) of the Study of Health in Pomerania were used for analysis in this study. MRI measurement of thoracic and abdominal aortic diameters was performed. Parameters for calculation of reference values according to age and sex analysis were provided. Multivariable linear regression models were used for determination of aortic diameter-related risk factors, including smoking, blood pressure (BP), high-density lipoprotein cholesterol (HDL-C). For the ascending aorta (β = -0.049, p < 0.001), the aortic arch (β = -0.061, p < 0.001) and the subphrenic aorta (β = -0.018, p = 0.004), the body surface area (BSA)-adjusted diameters were lower in men. Multivariable-adjusted models revealed significant increases in BSA-adjusted diameters with age for all six aortic segments (p < 0.001). Consistent results for all segments were observed for the positive associations of diastolic BP (β = 0.001; 0.004) and HDL (β = 0.035; 0.087) with BSA-adjusted aortic diameters and for an inverse association of systolic BP (β = -0.001). Some BSA-adjusted median aortic diameters are smaller in men than in women. All diameters increase with age, diastolic blood pressure and HDL-C and decrease as systolic BP increases. (orig.)

  17. Ionization-cluster distributions of alpha-particles in nanometric volumes of propane: measurement and calculation.

    Science.gov (United States)

    De Nardo, L; Colautti, P; Conte, V; Baek, W Y; Grosswendt, B; Tornielli, G

    2002-12-01

    The probability of the formation of ionization clusters by primary alpha-particles at 5.4 MeV in nanometric volumes of propane was studied experimentally and by Monte Carlo simulation, as a function of the distance between the center line of the particle beam and the center of the target volume. The volumes were of cylindrical shape, 3.7 mm in diameter and height. As the investigations were performed at gas pressures of 300 Pa and 350 Pa, the dimensions of the target volume were equivalent to 20.6 nm or 24.0 nm in a material of density 1.0 g/cm(3). The dependence of ionization-cluster formation on distance was studied up to values equivalent to about 70 nm. To validate the measurements, a Monte Carlo model was developed which allows the experimental arrangement and the interactions of alpha-particles and secondary electrons in the counter gas to be properly simulated. This model is supplemented by a mathematical formulation of cluster size formation in nanometric targets. The main results of our study are (i) that the mean ionization-cluster size in the delta-electron cloud of an alpha-particle track segment, decreases as a function of the distance between the center line of the alpha-particle beam and the center of the sensitive target volume to the power of 2.6, and (ii) that the mean cluster size in critical volumes and the relative variance of mean cluster size due to delta-electrons are invariant at distances greater than about 20 nm. We could imagine that the ionization-cluster formation in nanometric volumes might in future provide the physical basis for a redefinition of radiation quality.

  18. Juvenile wood volume and its proportion to stem volume vs. selected biometric features of Scots pine (Pinus sylvestris L. trees

    Directory of Open Access Journals (Sweden)

    Arkadiusz Tomczak

    2011-01-01

    Full Text Available The aim of the study was to determine whether there is a correlation between breast height diameter, tree height and stem total volume of Scots pines, on the one hand, and volume and proportion of juvenile wood, on the other. The investigations comprised pure pine stands of the IInd, IIIrd, IVth and Vth age classes developed in conditions of fresh mixed coniferous forest. A distinct curvilinear correlation was found between volume and proportion of juvenile wood in tree stems and breast height diameter, height and stem total volume. Because of high values of determination coefficients (R2, which characterised the above-mentioned correlations, it seems appropriate to use these regularities to assess the quality of the timber raw material regarding the proportions of its volume and juvenile wood in stems of Scots pine trees.

  19. Importance of length and external diameter in left ventricular geometry. Normal values from the HUNT Study

    Science.gov (United States)

    Støylen, Asbjørn; Mølmen, Harald E; Dalen, Håvard

    2016-01-01

    Background We aimed to study left ventricular (LV) geometry assessed by length (LVWL), external diameter (LVEDD) and relative wall thickness (RWT) in relation to age, body size and gender in healthy individuals. Methods 1266 individuals underwent echocardiography in the Nord-Trøndelag Health Study (HUNT3), Norway. Septum thickness (IVS), posterior wall thickness (LVPWd) and end-diastolic internal diameter (LVIDD) were measured in M-mode, and LVEDD was calculated as the sum. Myocardial wall lengths were measured in a straight line from apex to the mitral ring in apical views at end diastole and averaged to LVWL. RWT ([IVSd+LVPWd]/LVIDD) and the ratio between length and diameter (L/D) were calculated. Results Normal age-related and gender-related values are provided. Conventional measures conform to previous studies. All measures correlated with body surface area (BSA) (r 0.29–0.60), and BSA indexed values were higher in women. Wall thickness (WT) and LVEDD, but not LVIDD, were higher with higher age. LVWL and L/D were lower with increasing age, but L/D was independent of BSA and similar in women and men (1.41 vs 1.40). RWT correlated with BSA and age (r 0.17 and 0.34). Conclusions LV WT increases and LVWL decreases with higher age. Excluding length in LV mass calculations increasingly overestimates mass with ageing. L/D is a BSA independent measure of LV age-related geometry and may be useful as a body size independent measure in LV hypertrophy. RWT depends on body size and age, and a single cut-off value is not warranted. PMID:27752332

  20. Numerical investigation of scale effect of various injection diameters on interaction in cold kerosene-fueled supersonic flow

    Science.gov (United States)

    Zhu, Lin; Qi, Yin-Yin; Liu, Wei-Lai; Xu, Bao-Jian; Ge, Jia-Ru; Xuan, Xiang-Chun; Jen, Tien-Chien

    2016-12-01

    The incident shock wave generally has a strong effect on the transversal injection field in cold kerosene-fueled supersonic flow, possibly due to its affecting the interaction between incoming flow and fuel through various operation conditions. This study is to address scale effect of various injection diameters on the interaction between incident shock wave and transversal cavity injection in a cold kerosene-fueled scramjet combustor. The injection diameters are separately specified as from 0.5 to 1.5 mm in 0.5 mm increments when other performance parameters, including the injection angle, velocity and pressure drop are all constant. A combined three dimensional Couple Level Set & Volume of Fluids (CLSVOF) approach with an improved K-H & R-T model is used to characterize penetration height, span expansion area, angle of shock wave and sauter mean diameter (SMD) distribution of the kerosene droplets with/without considering evaporation. Our results show that the injection orifice surely has a great scale effect on the transversal injection field in cold kerosene-fueled supersonic flows. Our findings show that the penetration depth, span angle and span expansion area of the transverse cavity jet are increased with the injection diameter, and that the kerosene droplets are more prone to breakup and atomization at the outlet of the combustor for the orifice diameter of 1.5 mm. The calculation predictions are compared against the reported experimental measurements and literatures with good qualitative agreement. The simulation results obtained in this study can provide the evidences for better understanding the underlying mechanism of kerosene atomization in cold supersonic flow and scramjet design improvement.

  1. The dependence of the Schottky barrier height on carbon nanotube diameter for Pd-carbon nanotube contacts

    Energy Technology Data Exchange (ETDEWEB)

    Svensson, Johannes; Sourab, Abdelrahim A; Campbell, Eleanor E B [Department of Physics, Goeteborg University, SE-41296 Goeteborg (Sweden); Tarakanov, Yury [Department of Applied Physics, Chalmers University of Technology, SE-41296 Gothenburg (Sweden); Lee, Dong Su [Max-Planck-Institut fuer Festkoerperforschung, Heisenbergstrasse 1, D-70569 Stuttgart (Germany); Park, Seung Joo; Baek, Seung Jae; Park, Yung Woo [School of Physics, Seoul National University, Seoul 151-747 (Korea, Republic of)], E-mail: ywpark@phya.snu.ac.kr, E-mail: eleanor.campbell@ed.ac.uk

    2009-04-29

    Direct measurements are presented of the Schottky barrier (SB) heights of carbon nanotube devices contacted with Pd electrodes. The SB barrier heights were determined from the activation energy of the temperature-dependent thermionic emission current in the off-state of the devices. The barrier heights generally decrease with increasing diameter of the nanotubes and they are in agreement with the values expected when assuming little or no influence of Fermi level pinning.

  2. The dependence of the Schottky barrier height on carbon nanotube diameter for Pd-carbon nanotube contacts

    OpenAIRE

    Svensson, Johannes; Sourab, Abdelrahim A.; Tarakanov, Yury; Lee, Dong Su; Park, Seung Joo; Baek, Seung Jae; Park, Yung Woo; Campbell, Eleanor E. B.

    2009-01-01

    Direct measurements are presented of the Schottky barrier (SB) heights of carbon nanotube devices contacted with Pd electrodes. The SB barrier heights were determined from the activation energy of the temperature-dependent thermionic emission current in the off-state of the devices. The barrier heights generally decrease with increasing diameter of the nanotubes and they are in agreement with the values expected when assuming little or no influence of Fermi level pinning.

  3. BIHOURLY DIAGRAMS OF FORBUSH DECREASES

    Science.gov (United States)

    Bihourly diagrams were made of Forbush decreases of cosmic ray intensity as observed at Uppsala from 31 Aug 56 to 31 Dec 59, at Kiruna from Nov 56 to 31 Dec 59, and at Murchison Bay from 26 Aug 57 to 30 Apr 59. (Author)

  4. Physiology of cell volume regulation in vertebrates

    DEFF Research Database (Denmark)

    Hoffmann, Else K; Lambert, Ian H; Pedersen, Stine F

    2009-01-01

    cases, activation of volume regulatory osmolyte transport. After acute swelling, cell volume is regulated by the process of regulatory volume decrease (RVD), which involves the activation of KCl cotransport and of channels mediating K(+), Cl(-), and taurine efflux. Conversely, after acute shrinkage......, cell volume is regulated by the process of regulatory volume increase (RVI), which is mediated primarily by Na(+)/H(+) exchange, Na(+)-K(+)-2Cl(-) cotransport, and Na(+) channels. Here, we review in detail the current knowledge regarding the molecular identity of these transport pathways...... and their regulation by, e.g., membrane deformation, ionic strength, Ca(2+), protein kinases and phosphatases, cytoskeletal elements, GTP binding proteins, lipid mediators, and reactive oxygen species, upon changes in cell volume. We also discuss the nature of the upstream elements in volume sensing in vertebrate...

  5. Simple Analytic Expression with High Precision for the Barker-Henderson Diameter

    Institute of Scientific and Technical Information of China (English)

    孙久勋

    2003-01-01

    A fitting procedure is proposed to establish two analytic approximate expressions for the complicated Barker-Henderson (BH) diameter with Lennard-Jones potential in two temperature ranges. Considering that the differentiation is a process enlarging the errors and the integration decreasing the errors and that the derivative of BH diameter is important in the calculation of internal energy, we propose to fit the derivative directly, instead of usually fitting the original function and subsequently deriving its derivative. The simplicity and precision of two expressions developed are superior to the extensively used expressions in literature. The one with following form only has an average fitting 0.0063% in the reduced temperature range (0.4 ≤ kT/ε≤ 15), and can be extrapolated to a wider temperature range (0.4 ≤ kT/ε≤ 50) with an average error 0.13%, which is d/σ = 1.1755 + 0.02878 lnτ - 0.2072τ1/4 + 0.00463τ3/4.

  6. In vitro evaluation of Root ZX and Raypex 6 in teeth with different apical diameters

    Directory of Open Access Journals (Sweden)

    Ugur Aydin

    2015-01-01

    Full Text Available Background: There is a growing interest about electronic apex locators for working length determination. There are several studies dealing with their performance in different conditions. Aims: The aim of this study is to evaluate the accuracy of Root ZX and Raypex 6 in teeth with different apical diameters. Materials and Methods: Actual working length (AWL of 80 single rooted teeth were determined as 0.5 mm short of apical foramen. The teeth were divided into 4 groups (n = 20. First group (G 0 included teeth with mature apices. Root canals of the other groups (G 32, G 57 and G 72 were enlarged until apical sizes of 0.32, 0.57 and 0.72 mm were obtained. Samples were embedded in alginate and electronic measurements (EM were performed. Statistical analysis: was achieved with Fisher exact test. Results: Both devices revealed a high rate of success in G 0 and G 32. Their accuracy decreased significantly in G 57 and G 72 groups (P 0.05. Conclusions: Root ZX and Raypex 6 are reliable in teeth with mature apices. At foramen diameters exceeding 0.57 mm, their accuracy is susceptible.

  7. Experimental study on the near wake behind two side-by-side cylinders of unequal diameters

    Energy Technology Data Exchange (ETDEWEB)

    Gao Yangyang; Yu Dingyong [College of Engineering, Ocean University of China, Qingdao 266100 (China); Tan, Soonkeat [School of Civil and Environmental Engineering, Nanyang Technological University, Singapore 639798 (Singapore); Wang Xikun [Maritime Research Center, Nanyang Technological University, Singapore 639798 (Singapore); Hao Zhiyong, E-mail: gaoyangyangouc@163.co [Shanghai Maritime University, Shanghai 200135 (China)

    2010-10-15

    The wake structure behind two side-by-side circular cylinders with unequal diameter was investigated using the particle image velocimetry (PIV) technique. This investigation focused on the asymmetrical flow within the subcritical Reynolds number regime. A comparison between the time-averaged mean flow field of one cylinder and that of two side-by-side cylinders of unequal diameter was made for elucidating the mean flow characteristics attributable to the latter. The distribution of mean velocity behind two side-by-side unequal cylinders was distinctly different from that behind one cylinder, and an asymmetric combination was observed behind the two cylinders. The present paper also presents the authors' interpretation of the generation mechanism of gap flow deflection based on the instantaneous vorticity contours and velocity distribution. The effect of Reynolds number on flow structure was studied by analyzing the mean velocity distribution and time-averaged wake structures. The results showed that vortex formation length decreases with Reynolds number.

  8. Microbes make average 2 nanometer diameter crystalline UO2 particles.

    Science.gov (United States)

    Suzuki, Y.; Kelly, S. D.; Kemner, K. M.; Banfield, J. F.

    2001-12-01

    It is well known that phylogenetically diverse groups of microorganisms are capable of catalyzing the reduction of highly soluble U(VI) to highly insoluble U(IV), which rapidly precipitates as uraninite (UO2). Because biological uraninite is highly insoluble, microbial uranyl reduction is being intensively studied as the basis for a cost-effective in-situ bioremediation strategy. Previous studies have described UO2 biomineralization products as amorphous or poorly crystalline. The objective of this study is to characterize the nanocrystalline uraninite in detail in order to determine the particle size, crystallinity, and size-related structural characteristics, and to examine the implications of these for reoxidation and transport. In this study, we obtained U-contaminated sediment and water from an inactive U mine and incubated them anaerobically with nutrients to stimulate reductive precipitation of UO2 by indigenous anaerobic bacteria, mainly Gram-positive spore-forming Desulfosporosinus and Clostridium spp. as revealed by RNA-based phylogenetic analysis. Desulfosporosinus sp. was isolated from the sediment and UO2 was precipitated by this isolate from a simple solution that contains only U and electron donors. We characterized UO2 formed in both of the experiments by high resolution-TEM (HRTEM) and X-ray absorption fine structure analysis (XAFS). The results from HRTEM showed that both the pure and the mixed cultures of microorganisms precipitated around 1.5 - 3 nm crystalline UO2 particles. Some particles as small as around 1 nm could be imaged. Rare particles around 10 nm in diameter were also present. Particles adhere to cells and form colloidal aggregates with low fractal dimension. In some cases, coarsening by oriented attachment on \\{111\\} is evident. Our preliminary results from XAFS for the incubated U-contaminated sample also indicated an average diameter of UO2 of 2 nm. In nanoparticles, the U-U distance obtained by XAFS was 0.373 nm, 0.012 nm

  9. Modular Small Diameter Vascular Grafts with Bioactive Functionalities.

    Directory of Open Access Journals (Sweden)

    Meik Neufurth

    Full Text Available We report the fabrication of a novel type of artificial small diameter blood vessels, termed biomimetic tissue-engineered blood vessels (bTEBV, with a modular composition. They are composed of a hydrogel scaffold consisting of two negatively charged natural polymers, alginate and a modified chitosan, N,O-carboxymethyl chitosan (N,O-CMC. Into this biologically inert scaffold two biofunctionally active biopolymers are embedded, inorganic polyphosphate (polyP and silica, as well as gelatin which exposes the cell recognition signal, Arg-Gly-Asp (RGD. These materials can be hardened by exposure to Ca(2+ through formation of Ca(2+ bridges between the polyanions, alginate, N,O-CMC, and polyP (alginate-Ca(2+-N,O-CMC-polyP. The bTEBV are formed by pressing the hydrogel through an extruder into a hardening solution, containing Ca(2+. In this universal scaffold of the bTEBV biomaterial, polycations such as poly(L-Lys, poly(D-Lys or a His/Gly-tagged RGD peptide (three RGD units were incorporated, which promote the adhesion of endothelial cells to the vessel surface. The mechanical properties of the biopolymer material (alginate-Ca(2+-N,O-CMC-polyP-silica revealed a hardness (elastic modulus of 475 kPa even after a short incubation period in CaCl2 solution. The material of the artificial vascular grafts (bTEBVs with an outer size 6 mm and 1.8 mm, and an inner diameter 4 mm and 0.8 mm, respectively turned out to be durable in 4-week pulsatile flow experiments at an alternating pressure between 25 and 100 mbar (18.7 and 75.0 mm Hg. The burst pressure of the larger (smaller vessels was 850 mbar (145 mbar. Incorporation of polycationic poly(L-Lys, poly(D-Lys, and especially the His/Gly-tagged RGD peptide, markedly increased the adhesion of human, umbilical vein/vascular endothelial cells, EA.HY926 cells, to the surface of the hydrogel. No significant effect of the polyP samples on the clotting of human plasma is measured. We propose that the metabolically

  10. Decreases in Human Semen Quality with Age Among Healthy Men

    Energy Technology Data Exchange (ETDEWEB)

    Eskenazi, B.; Wyrobek, A.J.; Kidd, S.A.; Moore, L.; Young, S.S.; Moore, D.

    2001-12-01

    The objective of this report is to characterize the associations between age and semen quality among healthy active men after controlling for identified covariates. Ninety-seven healthy, nonsmoking men between 22 and 80 years without known fertility problems who worked for or retired from a large research laboratory. There was a gradual decrease in all semen parameters from 22-80 years of age. After adjusting for covariates, volume decreased 0.03 ml per year (p = 0.001); sperm concentration decreased 2.5% per year (p = 0.005); total count decreased 3.6% per year of age (p < 0.001); motility decreased 0.7% per year (P < 0.001); progressive motility decreased 3.1% per year (p < 0.001); and total progressively motile sperm decreased 4.8% per year (p < 0.001). In a group of healthy active men, semen volume, sperm concentration, total sperm count, and sperm motility decrease continuously between 22-80 years of age, with no evidence of a threshold.

  11. Experimental validation of a single shaped filter approach for CT using variable source-to-filter distance for examination of arbitrary object diameters.

    Science.gov (United States)

    Lück, Ferdinand; Kolditz, Daniel; Hupfer, Martin; Steiding, Christian; Kalender, Willi A

    2014-10-07

    The purpose of this study was to validate the use of a single shaped filter (SF) for computed tomography (CT) using variable source-to-filter distance (SFD) for the examination of different object diameters.A SF was designed by performing simulations with the purpose of achieving noise homogeneity in the reconstructed volume and dose reduction for arbitrary phantom diameters. This was accomplished by using a filter design method thats target is to achieve a homogeneous detector noise, but also uses a correction factor for the filtered back projection process. According to simulation results, a single SF designed for one of the largest phantom diameters meets the requirements for all diameters when SFD can be adjusted. To validate these results, a SF made of aluminium alloy was manufactured. Measurements were performed on a CT scanner with polymethyl methacrylate (PMMA) phantoms of diameters from 40-100 mm. The filter was positioned at SFDs ranging from 97-168 mm depending on the phantom diameter. Image quality was evaluated for the reconstructed volume by assessing CT value accuracy, noise homogeneity, contrast-to-noise ratio weighted by dose (CNRD) and spatial resolution. Furthermore, scatter distribution was determined with the use of a beam-stop phantom. Dose was measured for a PMMA phantom with a diameter of 100 mm using a calibrated ionization chamber.The application of a single SF at variable SFD led to improved noise uniformity and dose reduction: noise homogeneity was improved from 15% down to about 0%, and dose was reduced by about 37%. Furthermore, scatter dropped by about 32%, which led to reduced cupping artifacts and improved CT value accuracy. Spatial resolution and CNRD was not affected by the SF.By means of a single SF with variable SFD designed for CT, significant dose reduction can be achieved and image quality can be improved by reducing noise inhomogeneity as well as scatter-induced artifacts.

  12. Dexmedetomidine decreases the oral mucosal blood flow.

    Science.gov (United States)

    Kawaai, Hiroyoshi; Yoshida, Kenji; Tanaka, Eri; Togami, Kohei; Tada, Hitoshi; Ganzberg, Steven; Yamazaki, Shinya

    2013-12-01

    There is an abundance of blood vessels in the oral cavity, and intraoperative bleeding can disrupt operations. There have been some interesting reports about constriction of vessels in the oral cavity, one of which reported that gingival blood flow in cats is controlled by sympathetic α-adrenergic fibres that are involved with vasoconstriction. Dexmedetomidine is a sedative and analgesic agent that acts through the α-2 adrenoceptor, and is expected to have a vasoconstrictive action in the oral cavity. We have focused on the relation between the effects of α-adrenoceptors by dexmedetomidine and vasoconstriction in oral tissues, and assessed the oral mucosal blood flow during sedation with dexmedetomidine. The subjects comprised 13 healthy male volunteers, sedated with dexmedetomidine in a loading dose of 6 μg/kg/h for 10 min and a continuous infusion of 0.7 μg/kg/h for 32 min. The mean arterial pressure (MAP), heart rate (HR), cardiac output (CO), stroke volume (SV), systemic vascular resistance (SVR), and palatal mucosal blood flow (PMBF) were measured at 0, 5, 10, 12, 22, and 32 min after the start of the infusion. The HR, CO, and PBMF decreased significantly during the infusion even though there were no differences in the SV. The SVR increased significantly but the PMBF decreased significantly. In conclusion, PMBF was reduced by the mediating effect of dexmedetomidine on α-2 adrenoceptors.

  13. Self-assembling nano-diameter needlelike pinning centers in YBCO, utilizing a foreign element dopant

    Energy Technology Data Exchange (ETDEWEB)

    Sawh, Ravi-Persad [Texas Center for Superconductivity and Physics Department, University of Houston, 632 Science and Research Bldg 1, Houston Texas 77204-5005 (United States); Weinstein, Roy [Texas Center for Superconductivity and Physics Department, University of Houston, 632 Science and Research Bldg 1, Houston Texas 77204-5005 (United States); Obot, Victor [Department of Mathematics, Texas Southern University, 3100 Cleburne St, Houston Texas 77004-4597 (United States); Parks, Drew [Texas Center for Superconductivity and Physics Department, University of Houston, 632 Science and Research Bldg 1, Houston Texas 77204-5005 (United States); Gandini, Alberto [Texas Center for Superconductivity and Physics Department, University of Houston, 632 Science and Research Bldg 1, Houston Texas 77204-5005 (United States); Skorpenske, Harley [Texas Center for Superconductivity and Physics Department, University of Houston, 632 Science and Research Bldg 1, Houston Texas 77204-5005 (United States)

    2006-06-01

    Although pinning centers created by irradiation presently produce the highest J{sub c}, it is probable that ultimately these will be emulated by chemical pinning centers. The best pinning centers produced by irradiation nevertheless provide guidelines for desirable morphology of chemical pinning structures. The highest J{sub c} produced earlier in textured HTS was obtained using isotropic high-energy ions produced by fission of {sup 235}U. This so-called U/n process produces pinning centers of diameter {<=} 4.5 nm, with an effective length of {approx}2.7 {mu}m. Maximum J{sub c} occurs for pinning center density of {approx}10{sup 10} cm{sup -3}. We use this as a model for desired chemical pinning centers. Our approach to introducing chemical pinning centers has been to produce precipitates within the HTS containing elements not native to the HTS, and to seek needlelike (columnar) deposits of small diameter. We report here on the formation of needlelike or columnar deposits in textured Y123 containing a dopant foreign to Y123. It serves as a demonstration that self-assembling nanometer diameter columns utilizing a dopant foreign to the HTS system are a feasible goal. These deposits, however, do not fully meet the ultimate requirements of pinning centers because the desired deposits should be smaller. The self-assembling columns formed contain titanium, are {approx}500 nm in diameter, and up to 10 {mu}m long. The size and morphology of the deposits vary with the mass of admixed Ti dopant. J{sub c} is decreased for small dopant mass. At larger dopant masses needlelike precipitates form, and J{sub c} increases again. A small range of mass of admixed Ti exists in which J{sub c} is enhanced by pinning. In the range of admixed Ti mass studied in these experiments there is a negligible effect on T{sub c}. Magnetization studies of J{sub c} are also reported.

  14. Sustainable yields from large diameter wells in shallow weathered aquifers

    Science.gov (United States)

    Rushton, K. R.; de Silva, C. S.

    2016-08-01

    Large diameter wells in shallow weathered aquifers provide a valuable source of water for domestic and agricultural purposes in many locations including the Indian subcontinent. However, when used for irrigation, these wells often fail towards the end of the dry season. By considering two case studies in the dry and intermediate rainfall zones of Sri Lanka, reasons for the limited yield of these wells are identified. The first case study is concerned with a sloping catchment; a significant proportion of the precipitation during the rainy season either becomes runoff or passes down-gradient through the aquifer and is discharged at the ground surface. Furthermore, during the dry season, groundwater discharge continues. In the second case study the topography is generally flat but, even though the aquifer fills most years during the rainy season, there is often only sufficient water to irrigate about half of each farmer's holding. These investigations are based on field information and the development of conceptual and computational models. Of critical importance in assessing the long term yield of a well is the formation of a seepage face on the side of the well, with the water table a significant distance above the pumping water level. Consequently the water table may only be lowered to about half the depth of the well. The paper concludes with recommendations for the exploitation of groundwater from shallow weathered aquifers to minimise the risk of failure during the dry season.

  15. A 24mm diameter fibre positioner for spectroscopic surveys

    Science.gov (United States)

    Hörler, Philipp; Kronig, Luzius; Kneib, Jean-Paul; Bleuler, Hannes; Bouri, Mohamed

    2016-07-01

    One of the big research topics in modern cosmology is the mystery of dark Energy. To unveil the secret, cosmologists want to measure precisely the evolution of large scale structures in the universe. One way of doing so is to measure the 3D location of a high number of galaxies. By measuring the redshift of a galaxy, it is possible to find its distance. In order to measure a high number of galaxies in a practical amount of time, we need to observe multiple objects in parallel. Instead of a spectrograph, thousands of optical fibres are placed in the focal plane of a telescope. They will transmit the light of many objects to a spectrograph. Each fibre has to be positioned to several μm precision in the focal plane of a telescope for each exposure. Each fibre is positioned by a 2-axis fibre positioner. In this paper such a fibre positioner with 24-mm diameter is presented. It is driven by two brushless DC motors in combination with a backlash free gearbox. The positioner has an optimal central fibre path and improved angular alignment. The fibre runs through the centre of the positioner and is only bent at the top to reach its target position. In this way, the flexion and torsion of the fibre are minimal. In addition to the high positioning accuracy, the design is optimized to allow a minimal tilt error of the fibre. This is demonstrated using a novel optical tilt measurement system.

  16. Correlation Development for Sauter Mean Diameter of Rotary Atomizer

    Directory of Open Access Journals (Sweden)

    Murali.K

    2016-08-01

    Full Text Available Atomizers are of many types, among that simplex and duplex types of atomizers are used and recognized often as fuel injectors in aircrafts. Types of atomizers and features are read. Among many types of atomizer, rotary type of atomizer is selected due to its naked evident like easy retrofit to existing spreading system , able to handle large quantities, feed is possible, better economy, high peripheral speed and spread of droplets, uniform liquid feed rate, uniform distribution of feed, higher level of atomization etc., The rotary atomizer specifications and its features are listed, the droplets of rotary atomizer are visualized and readings are taken from experimental methods, such as Laser visualization method .After the droplets data alignment, the (SMD Sauter Mean Diameter is to be taken in and considered, SMD means it is a average particle (droplet size of a given particles, and it is further explained with its given relation. By SMD’s given equated form it is used to compare data between rotary atomizer particles and given particle size. By SMD it is simplified further and used to create a co-relation between SMD and rotary atomizer. The rotary atomizer data values are taken through out with the SMD to find and form a co-related derived pattern for ROTARY ATOMIZE

  17. More bounds on the diameters of convex polytopes

    CERN Document Server

    Bremner, David; Hua, William; Schewe, Lars

    2009-01-01

    Finding a good bound on the maximal edge diameter $\\Delta(d,n)$ of a polytope in terms of its dimension $d$ and the number of its facets $n$ is one of the basic open questions in polytope theory \\cite{BG}. Although some bounds are known, the behaviour of the function $\\Delta(d,n)$ is largely unknown. The Hirsch conjecture, formulated in 1957 and reported in \\cite{GD}, states that $\\Delta(d,n)$ is linear in $n$ and $d$: $\\Delta(d,n) \\leq n-d$. The conjecture is known to hold in small dimensions, i.e., for $d \\leq 3$ \\cite{VK}, along with other specific pairs of $d$ and $n$ (Table \\ref{before}). However, the asymptotic behaviour of $\\Delta(d,n)$ is not well understood: the best upper bound -- due to Kalai and Kleitman -- is quasi-polynomial \\cite{GKDK}. In this article we will show that $\\Delta(4,12)=7$ and present strong evidence for $\\Delta(5,12)=\\Delta(6,13)=7$. The first of these new values is of particular interest since it indicates that the Hirsch bound is not sharp in dimension 4.

  18. Thermal performance of different working fluids in a dual diameter circular heat pipe

    Directory of Open Access Journals (Sweden)

    S.M. Peyghambarzadeh

    2013-12-01

    Full Text Available In this paper, heat transfer performance of a 40 cm-length circular heat pipe with screen mesh wick is experimentally investigated. This heat pipe is made of copper with two diameters; larger in the evaporator and smaller in the adiabatic and condenser. Three different liquids including water, methanol, and ethanol are separately filled within the heat pipe. Low heat fluxes are applied (up to 2500 W/m2 in the evaporator and constant temperature water bath is used at three levels including 15, 25, and 35 °C in the condenser. Results demonstrate that higher heat transfer coefficients are obtained for water and ethanol in comparison with methanol. Furthermore, increasing heat flux increases the evaporator heat transfer coefficient. For the case of methanol, some degradation in heat transfer coefficient is occurred at high heat fluxes which can be due to the surface dryout effect. Increasing the inclination angle decreases the heat pipe thermal resistance.

  19. Characteristics of Microwave Discharge in a Modified Surfaguide with a Large Diameter

    Institute of Scientific and Technical Information of China (English)

    DING Zhen-Feng(丁振峰); P. Tristant; J. Desmaison; DONG Chuang(董闯); WANG You-Nian(王友年)

    2003-01-01

    The characteristics of the microwave discharge are studied in a modified surfaguide with a large diameter. Experimental results show that there exist three discharging modes, one is the plasma mode, and the others are the waveguide modes. The discharge can jump between one of the waveguide modes and the plasma mode, and the corresponding hysteresis loop is influenced by the discharging pressure. In the higher pressure region, the hysteresis loop is wide enough so that the discharge in each mode is stable. In the middle pressure region, the discharge becomes unstable as a result of the hysteresis loop being sufficiently narrow. When the gas pressure is further decreased, the plasma mode disappears, while the mode jumps between the two waveguide modes always appear and are stable in the discharge region we have explored.

  20. Experiment and simulation of launching process of a small-diameter steel cartridge case

    Institute of Scientific and Technical Information of China (English)

    Han-dong ZHAO; Jia-qing XIE; Zhi-peng LI; Hui-suo ZHANG

    2014-01-01

    In order to explore the rules of the deformation force during the launching of a small-diameter steel cartridge, the semi-closed bomb test method is used to test the greatest strains on chamber outer wall under the different chamber pressures. The pressure curves of cartridge chamber are measured in experiment, and the tensile test data of cartridge are loaded into the numerical calculation to compare with the experimental data. The conclusion was obtained that the calculated results match better with the experimental results by considering strain rate bilinear kinematic hardening material constitutive model. The forces on the various parts of the cartridge during launching and their deformation rules are achieved, in which the equivalent plastic strain decreases and the cylinder ring withstands the maximum equivalent stress when the cartridge case clings to the bore from the mouth to the bottom.

  1. Decreasing incidence rates of bacteremia

    DEFF Research Database (Denmark)

    Nielsen, Stig Lønberg; Pedersen, C; Jensen, T G

    2014-01-01

    BACKGROUND: Numerous studies have shown that the incidence rate of bacteremia has been increasing over time. However, few studies have distinguished between community-acquired, healthcare-associated and nosocomial bacteremia. METHODS: We conducted a population-based study among adults with first......-time bacteremia in Funen County, Denmark, during 2000-2008 (N = 7786). We reported mean and annual incidence rates (per 100,000 person-years), overall and by place of acquisition. Trends were estimated using a Poisson regression model. RESULTS: The overall incidence rate was 215.7, including 99.0 for community......-acquired, 50.0 for healthcare-associated and 66.7 for nosocomial bacteremia. During 2000-2008, the overall incidence rate decreased by 23.3% from 254.1 to 198.8 (3.3% annually, p bacteremia decreased by 25.6% from 119.0 to 93.8 (3.7% annually, p

  2. Life satisfaction decreases during adolescence.

    Science.gov (United States)

    Goldbeck, Lutz; Schmitz, Tim G; Besier, Tanja; Herschbach, Peter; Henrich, Gerhard

    2007-08-01

    Adolescence is a developmental phase associated with significant somatic and psychosocial changes. So far there are few studies on developmental aspects of life satisfaction. This cross-sectional study examines the effects of age and gender on adolescent's life satisfaction. 1,274 German adolescents (aged 11-16 years) participated in a school-based survey study. They completed the adolescent version of the Questions on Life Satisfaction (FLZ(M) - Fragen zur Lebenszufriedenheit), a multidimensional instrument measuring the subjective importance and satisfaction with eight domains of general and eight domains of health-related life satisfaction. Effects of gender and age were analysed using ANOVAs. Girls reported significantly lower general (F = 5.0; p = .025) and health-related life satisfaction (F = 25.3; p life domains, there was a significant decrease in general (F = 14.8; p life satisfaction (F = 8.0; p Satisfaction with friends remained on a high level, whereas satisfaction with family relations decreased. Only satisfaction with partnership/sexuality increased slightly, however this effect cannot compensate the general loss of satisfaction. Decreasing life satisfaction has to be considered as a developmental phenomenon. Associations with the increasing prevalence of depression and suicidal ideation during adolescence are discussed. Life satisfaction should be considered a relevant aspect of adolescent's well-being and functioning.

  3. A computational algorithm addressing how vessel length might depend on vessel diameter.

    Science.gov (United States)

    Cai, Jing; Zhang, Shuoxin; Tyree, Melvin T

    2010-07-01

    The objective of this method paper was to examine a computational algorithm that may reveal how vessel length might depend on vessel diameter within any given stem or species. The computational method requires the assumption that vessels remain approximately constant in diameter over their entire length. When this method is applied to three species or hybrids in the genus Populus, vessel length is sometimes a linear function of vessel diameter and sometimes an exponential function of vessel diameter within a stem, based on R(2) values. Our results give within-species variation of vessel length versus diameter, and we compare this to between-species variation of mean diameter versus mean length.

  4. Diameter Control and Photoluminescence of ZnO Nanorods from Trialkylamines

    Directory of Open Access Journals (Sweden)

    Tamar Andelman

    2007-01-01

    Full Text Available A novel solution method to control the diameter of ZnO nanorods is reported. Small diameter (2-3 nm nanorods were synthesized from trihexylamine, and large diameter (50–80 nm nanorods were synthesized by increasing the alkyl chain length to tridodecylamine. The defect (green emission of the photoluminescence (PL spectra of the nanorods varies with diameter, and can thus be controlled by the diameter control. The small ZnO nanorods have strong green emission, while the large diameter nanorods exhibit a remarkably suppressed green band. We show that this observation supports surface oxygen vacancies as the defect that gives rise to the green emission.

  5. Reading the primary structure of a protein with 0.07 nm3 resolution using a subnanometre-diameter pore

    Science.gov (United States)

    Kennedy, Eamonn; Dong, Zhuxin; Tennant, Clare; Timp, Gregory

    2016-11-01

    The primary structure of a protein consists of a sequence of amino acids and is a key factor in determining how a protein folds and functions. However, conventional methods for sequencing proteins, such as mass spectrometry and Edman degradation, suffer from short reads and lack sensitivity, so alternative approaches are sought. Here, we show that a subnanometre-diameter pore, sputtered through a thin silicon nitride membrane, can be used to detect the primary structure of a denatured protein molecule. When a denatured protein immersed in electrolyte is driven through the pore by an electric field, measurements of a blockade in the current reveal nearly regular fluctuations, the number of which coincides with the number of residues in the protein. Furthermore, the amplitudes of the fluctuations are highly correlated with the volumes that are occluded by quadromers (four residues) in the primary structure. Each fluctuation, therefore, represents a read of a quadromer. Scrutiny of the fluctuations reveals that the subnanometre pore is sensitive enough to read the occluded volume that is related to post-translational modifications of a single residue, measuring volume differences of ∼0.07 nm3, but it is not sensitive enough to discriminate between the volumes of all twenty amino acids.

  6. Comparison of CT-Determined Pulmonary Artery Diameter, Aortic Diameter, and Their Ratio in Healthy and Diverse Clinical Conditions.

    Directory of Open Access Journals (Sweden)

    Sang Hoon Lee

    Full Text Available The main pulmonary artery diameter (mPA, aortic diameter (Ao, and the mPA/Ao ratio, easily measured using chest computed tomography (CT, provide information that enables the diagnosis and evaluation of cardiopulmonary diseases. Here, we used CT to determine the sex- and age-specific distribution of normal reference values for mPA, Ao, and mPA/Ao ratio in an adult Korean population.Data from non-contrast, ECG-gated, coronary-calcium-scoring CT images of 2,547 individuals who visited the Health Screening Center of the Severance Hospital were analyzed. Healthy individuals (n = 813 included those who do not have hypertension, diabetes, asthma, obstructive lung disease, ischemic heart disease, stroke, smoking, obesity, and abnormal CT findings. Both mPA and Ao were measured at the level of bifurcation of the main pulmonary artery.The mean mPA and Ao were 25.9 mm and 30.0 mm in healthy participants, respectively, while the mean mPA/Ao ratio was 0.87. Medical conditions associated with a larger mPA were male, obesity, smoking history, hypertension, and diabetes. A larger mPA/Ao ratio was associated with female, the obese, non-smoker, normotensive, and normal serum level of lipids, while a smaller mPA/Ao ratio was associated with older age. In healthy individuals, the 90th percentile sex-specific mPA, Ao, and mPA/Ao ratio were, 31.3 mm (95% CI 29.9-32.2, 36.8 mm (95% CI 35.7-37.5, and 1.05 (95% CI 0.99-1.07 in males, and 29.6 mm (95% CI 29.1-30.2, 34.5 mm (95% CI 34.1-34.9, and 1.03 (95% CI 1.02-1.06 in females, respectively.In the Korean population, the mean mPA reference values in male and female were 26.5 mm and 25.8 mm, respectively, while the mean mPA/Ao ratio was 0.87. These values were influenced by a variety of underlying medical conditions.

  7. Comparing Johnson’s SBB, Weibull and Logit-Logistic bivariate distributions for modeling tree diameters and heights using copulas

    Directory of Open Access Journals (Sweden)

    Jose Javier Gorgoso-Varela

    2016-04-01

    Full Text Available Aim of study: In this study we compare the accuracy of three bivariate distributions: Johnson’s SBB, Weibull-2P and LL-2P functions for characterizing the joint distribution of tree diameters and heights.Area of study: North-West of Spain.Material and methods: Diameter and height measurements of 128 plots of pure and even-aged Tasmanian blue gum (Eucalyptus globulus Labill. stands located in the North-west of Spain were considered in the present study. The SBB bivariate distribution was obtained from SB marginal distributions using a Normal Copula based on a four-parameter logistic transformation. The Plackett Copula was used to obtain the bivariate models from the Weibull and Logit-logistic univariate marginal distributions. The negative logarithm of the maximum likelihood function was used to compare the results and the Wilcoxon signed-rank test was used to compare the related samples of these logarithms calculated for each sample plot and each distribution.Main results: The best results were obtained by using the Plackett copula and the best marginal distribution was the Logit-logistic.Research highlights: The copulas used in this study have shown a good performance for modeling the joint distribution of tree diameters and heights. They could be easily extended for modelling multivariate distributions involving other tree variables, such as tree volume or biomass.

  8. Anatomical and Functional Estimations of Brachial Artery Diameter and Elasticity Using Oscillometric Measurements with a Quantitative Approach.

    Science.gov (United States)

    Yoshinaga, Keiichiro; Fujii, Satoshi; Tomiyama, Yuuki; Takeuchi, Keisuke; Tamaki, Nagara

    2016-07-01

    Noninvasive vascular function measurement plays an important role in detecting early stages of atherosclerosis and in evaluating therapeutic responses. In this regard, recently, new vascular function measurements have been developed. These new measurements have been used to evaluate vascular function in coronary arteries, large aortic arteries, or peripheral arteries. Increasing vascular diameter represents vascular remodeling related to atherosclerosis. Attenuated vascular elasticity may be a reliable marker for atherosclerotic risk assessment. However, previous measurements for vascular diameter and vascular elasticity have been complex, operator-dependent, or invasive. Therefore, simple and reliable approaches have been sought. We recently developed a new automated oscillometric method to measure the estimated area (eA) of a brachial artery and its volume elastic modulus (VE). In this review, we further report on this new measurement and other vascular measurements. We report on the reliability of the new automated oscillometric measurement of eA and VE. Based on our findings, this measurement technique should be a reliable approach, and this modality may have practical application to automatically assess muscular artery diameter and elasticity in clinical or epidemiological settings. In this review, we report the characteristics of our new oscillometric measurements and other related vascular function measurements.

  9. Automated image analysis for diameters and branching points of cerebral penetrating arteries and veins captured with two-photon microscopy.

    Science.gov (United States)

    Sugashi, Takuma; Yoshihara, Kouichi; Kawaguchi, Hiroshi; Takuwa, Hiroyuki; Ito, Hiroshi; Kanno, Iwao; Yamada, Yukio; Masamoto, Kazuto

    2014-01-01

    The present study was aimed to characterize 3-dimensional (3D) morphology of the cortical microvasculature (e.g., penetrating artery and emerging vein), using two-photon microscopy and automated analysis for their cross-sectional diameters and branching positions in the mouse cortex. We observed that both artery and vein had variable cross-sectional diameters across cortical depths. The mean diameter was similar for both artery (17 ± 5 μm) and vein (15 ± 5 μm), and there were no detectable differences over depths of 50-400 μm. On the other hand, the number of branches was slightly increased up to 400-μm depth for both the artery and vein. The mean number of branches per 0.1 mm vessel length was 1.7 ± 1.2 and 3.8 ± 1.6 for the artery and vein, respectively. This method allows for quantification of the large volume data of microvascular images captured with two-photon microscopy. This will contribute to the morphometric analysis of the cortical microvasculature in functioning brains.

  10. Correlation between diameter and testicular sperm quality in sheep’s creole, municipality of Soracá Boyacá

    Directory of Open Access Journals (Sweden)

    Nestor Palacios Moreno

    2012-11-01

    Full Text Available This study presents the correlation between testicular diameter (TD and sperm quality in a group of native sheep in the town of Soracá Boyacá, for possible selection values , considering the importance of reproduction in the sheep-culture and the search efficiency in the selection and management of players. The evaluation procedure was carried out by testing macroscopic and microscopic semen quality and testicular size measurement over a specific measuring tape for the case of comparing the diameters testicular ultrasonography was used as complementary test. The correlation of the results with respect to DT semen parameters (macroscopic and microscopic as volume (V, sperm concentration (SC, mass motility (MM and individual motility (MI was significant, as evidenced by the coefficient correlation of 0.81 between DT and CE. The correlation coefficients between DT and V, DT and MI were low with 0.29 and 0.27 respectively, recorded the lowest correlation was present between DT and MM with 0.09. This leads to the conclusion that the greater the testicular diameter (TD better sperm quality, and their values can serve as indicators as to the fertility of native sheep breeding males in seminal samples collected by electro-ejaculator.

  11. Influence of impeller diameter on overall gas dispersion properties in a sparged multi-impeller stirred tank☆

    Institute of Scientific and Technical Information of China (English)

    Yuyun Bao; Bingjie Wang; Mingli Lin; Zhengming Gao; Jie Yang

    2015-01-01

    The impeller configuration with a six parabolic blade disk turbine below two down-pumping hydrofoil propel-lers, identified as PDT+2CBY, was used in this study. The effect of the impeller diameter D, ranging from 0.30T to 0.40T (T as the tank diameter), on gas dispersion in a stirred tank of 0.48 m diameter was investigated by experimental and CFD simulation methods. Power consumption and total gas holdup were measured for the same impeller configuration PDT+2CBY with four different D/T. Results show that with D/T increases from 0.30 to 0.40, the relative power demand (RPD) in a gas–liquid system decreases slightly. At low superficial gas velocity VS of 0.0078 m·s−1, the gas holdup increases evidently with the increase of D/T. However, at high superficial gas velocity, the system with D/T=0.33 gets a good balance between the gas recirculation and liquid shearing rate, which resulted in the highest gas holdup among four different D/T. CFD simulation based on the two-fluid model along with the Population Balance Model (PBM) was used to investigate the effect of impeller diameter on the gas dispersion. The power consumption and total gas holdup predicted by CFD simulation were in reasonable agreement with the experimental data.

  12. Assessing Pain Using the Variation Coefficient of Pupillary Diameter.

    Science.gov (United States)

    Charier, David J; Zantour, Daniel; Pichot, Vincent; Chouchou, Florian; Barthelemy, Jean-Claude M; Roche, Frederic; Molliex, Serge B

    2017-07-13

    Pupillary diameter (PD) varies under the influence of the sympathetic as well as parasympathetic systems, increasing proportionally with pain intensity. Such variations however, should not be confused with pupillary fluctuations, which refer to the fast and permanent PD fluctuations induced by the ongoing interplay between the sympathetic and parasympathetic systems, which we propose to measure using the variation coefficient of PD (VCPD). This study aimed first at correlating PD, PD increase during a contraction, and VCPD, with pain rated using a numeric rating scale (NRS) during obstetrical labor, and then at comparing such correlations with each other. Forty patients were included in the study, and 160 simultaneous ratings (NRS, PD, and VCPD) were taken: 40 in the presence of uterine contractions and 40 in the absence of such contractions, before and 20 minutes after epidural analgesia. VCPD correlates more strongly (r = .77) than PD increase (r = .42) with pain rated using a NRS. The ability of VCPD to predict the occurrence of NRS scores ≥4 during obstetrical labor is .97 (confidence interval, .93-1.0). When measured over 10 seconds during contraction, VCPD correlates more strongly than PD increase with pain rated using the NRS. Such stronger correlation allows for an easy assessment of antinociception-nociception balance. The VCPD allows for an objective assessment of pain in laboring women. It could allow for an easy assessment of pain in noncommunicating patients: newborns or very old patients, patients with serious psychological conditions, assessment during the immediate postoperative period, or in intensive care units. Copyright © 2017 American Pain Society. Published by Elsevier Inc. All rights reserved.

  13. Solar Diameter Measurements from Eclipses as a Solar Variability Proxy

    Science.gov (United States)

    Waring Dunham, David; Sofia, Sabatino; Guhl, Konrad; Herald, David Russell

    2015-08-01

    Since thermal relaxation times for the Sun are thousands of years, small variations of the Solar intensity are proportional to small variations of the Solar diameter on decadal time scales. In a combination between observations and theory, reliable values of the relation constant W are known, that allow transformation of historical variations of radius into variations of the solar luminosity. During the past 45 years, members of the International Occultation Timing Association (IOTA) have observed 20 annular and total solar eclipses from locations near the path edges. Baily’s beads, whose occurrence and duration are considerably prolonged as seen from path edge locations, were first timed visually, mostly using projection techniques, but since about 1980, they have been timed mainly from analysis of video recordings. The edge locations have the advantage that most of the beads are defined by the same features in the lunar polar regions that cause the phenomena at each eclipse. Some of the best-observed modern eclipses can be used to assess the accuracy of the results, which are limited mainly by the intensity drop at the Sun’s edge, and the consequent uncertainty in defining the edge. In addition, direct visual contact timings made near the path edges during earlier eclipses, back to 1715, have been found in the literature, and analyzed. Although the observations seem to show small variations, they are only a little larger than the assessed accuracies. The results can be improved with a consistent re-analysis of the observations using the much more accurate lunar profile data that is now available from the Japanese Kaguya and NASA’s LRO lunar orbiter observations. Also, IOTA has plans to observe future eclipses with a variety of techniques that were used in the past, to better assess the accuracies of the different observational methods that have been used, and determine any systematic differences between them.

  14. AUTOMATED WATER LEVEL MEASUREMENTS IN SMALL-DIAMETER AQUIFER TUBES

    Energy Technology Data Exchange (ETDEWEB)

    PETERSEN SW; EDRINGTON RS; MAHOOD RO; VANMIDDLESWORTH PE

    2011-01-14

    Groundwater contaminated with hexavalent chromium, strontium-90, and uranium discharges into the Columbia River along approximately 16 km (10 mi) of the shoreline. Various treatment systems have and will continue to be implemented to eliminate the impact of Hanford Site contamination to the river. To optimize the various remediation strategies, it is important to understand interactions between groundwater and the surface water of the Columbia River. An automated system to record water levels in aquifer sampling tubes installed in the hyporheic zone was designed and tested to (1) gain a more complete understanding of groundwater/river water interactions based on gaining and losing conditions ofthe Columbia River, (2) record and interpret data for consistent and defensible groundwater/surface water conceptual models that may be used to better predict subsurface contaminant fate and transport, and (3) evaluate the hydrodynamic influence of extraction wells in an expanded pump-and-treat system to optimize the treatment system. A system to measure water levels in small-diameter aquifer tubes was designed and tested in the laboratory and field. The system was configured to allow manual measurements to periodically calibrate the instrument and to permit aquifer tube sampling without removing the transducer tube. Manual measurements were collected with an e-tape designed and fabricated especially for this test. Results indicate that the transducer system accurately records groundwater levels in aquifer tubes. These data are being used to refine the conceptual and numeric models to better understand interactions in the hyporheic zone of the Columbia River and the adjacent river water and groundwater, and changes in hydrochemistry relative to groundwater flux as river water recharges the aquifer and then drains back out in response to changes in the river level.

  15. Integrated spectral study of small angular diameter galactic open clusters

    Science.gov (United States)

    Clariá, J. J.; Ahumada, A. V.; Bica, E.; Pavani, D. B.; Parisi, M. C.

    2017-10-01

    This paper presents flux-calibrated integrated spectra obtained at Complejo Astronómico El Leoncito (CASLEO, Argentina) for a sample of 9 Galactic open clusters of small angular diameter. The spectra cover the optical range (3800-6800 Å), with a resolution of ∼14 Å. With one exception (Ruprecht 158), the selected clusters are projected into the fourth Galactic quadrant (282o < l < 345o) near the Galactic plane (∣b∣ ≤ 9o). We performed simultaneous estimates of foreground interstellar reddening and age by comparing the continuum distribution and line strenghts of the cluster spectra with those of template cluster spectra with known parameters. We thus provide spectroscopic information independent from that derived through color-magnitude diagram studies. We found three clusters (Collinder 249, NGC 4463 and Ruprecht 122) younger than ∼40 Myr, four moderately young ones (BH 92, Harvard 5, Hogg 14 and Pismis 23) with ages within 200-400 Myr, and two intermediate-age ones (Ruprecht 158 and ESO 065-SC07) with ages within 1.0-2.2 Gyr. The derived foreground E(B - V) color excesses vary from around 0.0 in Ruprecht 158 to ∼1.1 in Pismis 23. In general terms, the results obtained show good agreement with previous photometric results. In Ruprecht 158 and BH 92, however, some differences are found between the parameters here obtained and previous values in the literature. Individual spectra of some comparatively bright stars located in the fields of 5 out of the 9 clusters here studied, allowed us to evaluate their membership status. The current cluster sample complements that of 46 open clusters previously studied by our group in an effort to gather a spectral library with several clusters per age bin. The cluster spectral library that we have been building is an important tool to tie studies of resolved and unresolved stellar content.

  16. Decreasing Fires in Mediterranean Europe.

    Directory of Open Access Journals (Sweden)

    Marco Turco

    Full Text Available Forest fires are a serious environmental hazard in southern Europe. Quantitative assessment of recent trends in fire statistics is important for assessing the possible shifts induced by climate and other environmental/socioeconomic changes in this area. Here we analyse recent fire trends in Portugal, Spain, southern France, Italy and Greece, building on a homogenized fire database integrating official fire statistics provided by several national/EU agencies. During the period 1985-2011, the total annual burned area (BA displayed a general decreasing trend, with the exception of Portugal, where a heterogeneous signal was found. Considering all countries globally, we found that BA decreased by about 3020 km2 over the 27-year-long study period (i.e. about -66% of the mean historical value. These results are consistent with those obtained on longer time scales when data were available, also yielding predominantly negative trends in Spain and France (1974-2011 and a mixed trend in Portugal (1980-2011. Similar overall results were found for the annual number of fires (NF, which globally decreased by about 12600 in the study period (about -59%, except for Spain where, excluding the provinces along the Mediterranean coast, an upward trend was found for the longer period. We argue that the negative trends can be explained, at least in part, by an increased effort in fire management and prevention after the big fires of the 1980's, while positive trends may be related to recent socioeconomic transformations leading to more hazardous landscape configurations, as well as to the observed warming of recent decades. We stress the importance of fire data homogenization prior to analysis, in order to alleviate spurious effects associated with non-stationarities in the data due to temporal variations in fire detection efforts.

  17. Technologies for Decreasing Mining Losses

    Science.gov (United States)

    Valgma, Ingo; Väizene, Vivika; Kolats, Margit; Saarnak, Martin

    2013-12-01

    In case of stratified deposits like oil shale deposit in Estonia, mining losses depend on mining technologies. Current research focuses on extraction and separation possibilities of mineral resources. Selective mining, selective crushing and separation tests have been performed, showing possibilities of decreasing mining losses. Rock crushing and screening process simulations were used for optimizing rock fractions. In addition mine backfilling, fine separation, and optimized drilling and blasting have been analyzed. All tested methods show potential and depend on mineral usage. Usage in addition depends on the utilization technology. The questions like stability of the material flow and influences of the quality fluctuations to the final yield are raised.

  18. Does Respiratory Variation in Inferior Vena Cava Diameter Predict Fluid Responsiveness: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Long, Elliot; Oakley, Ed; Duke, Trevor; Babl, Franz E

    2017-05-01

    The aim of fluid resuscitation is to increase stroke volume, yet this effect is observed in only 50% of patients. Prediction of fluid responsiveness may allow fluid resuscitation to be administered to those most likely to benefit. The aim of this study was to systematically review the test characteristics of respiratory variation in inferior vena cava (IVC) diameter as a predictor of fluid responsiveness in patients with acute circulatory failure. Electronic searches combined with reference review of identified studies. Prospective observational studies of all patient groups and ages that used a recognized reference standard, stratified participants into fluid responders and fluid non-responders, and used summary statistics to describe their results were selected for inclusion. Study design, size, setting, patient population, use of mechanical ventilation and tidal volume, definition of fluid responsiveness, fluid challenge strategy, and summary statistics were abstracted. Quality assessment was performed using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) domains. Seventeen studies involving 533 patients were included, in whom 253 (47%) were fluid responders. The pooled sensitivity and specificity for a positive IVC ultrasound as a predictor of fluid responsiveness were 0.63 (95% confidence interval [CI]: 0.56-0.69) and 0.73 (95% CI: 0.67-0.78), respectively, with a pooled area under the receiver operating characteristic curve of 0.79 (standard error 0.05). In subgroup analysis, respiratory variation in IVC diameter was a better predictor of fluid responsiveness in mechanically ventilated patients. Respiratory variation in IVC diameter has limited ability to predict fluid responsiveness, particularly in spontaneously ventilating patients. A negative test cannot be used to rule out fluid responsiveness. Clinical context should be taken into account when using IVC ultrasound to help make treatment decisions.

  19. Adaptive circle-ellipse fitting method for estimating tree diameter based on single terrestrial laser scanning

    Science.gov (United States)

    Bu, Guochao; Wang, Pei

    2016-04-01

    Terrestrial laser scanning (TLS) has been used to extract accurate forest biophysical parameters for inventory purposes. The diameter at breast height (DBH) is a key parameter for individual trees because it has the potential for modeling the height, volume, biomass, and carbon sequestration potential of the tree based on empirical allometric scaling equations. In order to extract the DBH from the single-scan data of TLS automatically and accurately within a certain range, we proposed an adaptive circle-ellipse fitting method based on the point cloud transect. This proposed method can correct the error caused by the simple circle fitting method when a tree is slanted. A slanted tree was detected by the circle-ellipse fitting analysis, then the corresponding slant angle was found based on the ellipse fitting result. With this information, the DBH of the trees could be recalculated based on reslicing the point cloud data at breast height. Artificial stem data simulated by a cylindrical model of leaning trees and the scanning data acquired with the RIEGL VZ-400 were used to test the proposed adaptive fitting method. The results shown that the proposed method can detect the trees and accurately estimate the DBH for leaning trees.

  20. Soot properties and species measurements in a two-meter diameter JP-8 pool fire.

    Energy Technology Data Exchange (ETDEWEB)

    Shaddix, Christopher R.; Murphy, Jeffrey J.

    2003-06-01

    A tunable diode laser absorption spectroscopy probe was used to measure in situ soot properties and species concentrations in two-meter diameter JP-8 pool fires. Twelve tests were performed at the Lurance Canyon Bum Site operated by Sandia in Albuquerque, New Mexico. Seven of the tests were conducted with the probe positioned close to the centerline at heights above the pool surface ranging from 0.5 m to 2.0 mm in 0.25 m increments. For the remaining five tests, the probe was positioned at two heights 0.3 m from the centerline and at three heights 0.5 m from the centerline. Soot concentration was determined using a soot absorption measurement based on the transmission of a solid-state red laser (635 nm) through the 3.7 cm long probe volume. Soot temperature and a second estimate of soot concentration were measured using two-color optical pyrometry at 850 nm and la00 nm. The effective data rate for these measurements was 10 Mz. Finally, tunable diode laser absorption spectroscopy was used to qualitatively estimate water concentration at a rate of 1 kHz. To improve signal-to-noise, these data were averaged to an effective rate of 2 Hz. The results presented include the statistics, probability density functions, and spectral density functions of soot concentration, soot temperature, and approximate water concentrations at the different measurement locations throughout the fire.

  1. CALIFA: a diameter-selected sample for an integral field spectroscopy galaxy survey

    CERN Document Server

    Walcher, C J; Bekeraité, S; Husemann, B; Iglesias-Páramo, J; Backsmann, N; Ballesteros, J Barrera; Catalán-Torrecilla, C; Cortijo, C; del Olmo, A; Lorenzo, B Garcia; Falcón-Barroso, J; Jilkova, L; Kalinova, V; Mast, D; Marino, R A; Méndez-Abreu, J; Pasquali, A; Sánchez, S F; Trager, S; Zibetti, S; Aguerri, J A L; Alves, J; Bland-Hawthorn, J; Boselli, A; Morales, A Castillo; Fernandes, R Cid; Flores, H; Galbany, L; Gallazzi, A; García-Benito, R; de Paz, A Gil; González-Delgado, R M; Jahnke, K; Jungwiert, B; Kehrig, C; Lyubenova, M; Perez, I Márquez; Masegosa, J; Ibero, A Monreal; Pérez, E; Quirrenbach, A; Rosales-Ortega, F F; Roth, M M; Sanchez-Blazquez, P; Spekkens, K; Tundo, E; van de Ven, G; Verheijen, M A W; Vilchez, J V; Ziegler, B

    2014-01-01

    We describe and discuss the selection procedure and statistical properties of the galaxy sample used by the Calar Alto Legacy Integral Field Area Survey (CALIFA), a public legacy survey of 600 galaxies using integral field spectroscopy. The CALIFA "mother sample" was selected from the Sloan Digital Sky Survey (SDSS) DR7 photometric catalogue to include all galaxies with an r-band isophotal major axis between 45" and 79.2" and with a redshift 0.005 Mr > -23.1 and over a stellar mass range between 10^9.7 and 10^11.4Msun. In particular, within these ranges, the diameter selection does not lead to any significant bias against - or in favour of - intrinsically large or small galaxies. Only below luminosities of Mr = -19 (or stellar masses < 10^9.7Msun) is there a prevalence of galaxies with larger isophotal sizes, especially of nearly edge-on late-type galaxies, but such galaxies form < 10% of the full sample. We estimate volume-corrected distribution functions in luminosities and sizes and show that these ...

  2. Age estimation from canine volumes.

    Science.gov (United States)

    De Angelis, Danilo; Gaudio, Daniel; Guercini, Nicola; Cipriani, Filippo; Gibelli, Daniele; Caputi, Sergio; Cattaneo, Cristina

    2015-08-01

    Techniques for estimation of biological age are constantly evolving and are finding daily application in the forensic radiology field in cases concerning the estimation of the chronological age of a corpse in order to reconstruct the biological profile, or of a living subject, for example in cases of immigration of people without identity papers from a civil registry. The deposition of teeth secondary dentine and consequent decrease of pulp chamber in size are well known as aging phenomena, and they have been applied to the forensic context by the development of age estimation procedures, such as Kvaal-Solheim and Cameriere methods. The present study takes into consideration canines pulp chamber volume related to the entire teeth volume, with the aim of proposing new regression formulae for age estimation using 91 cone beam computerized scans and a freeware open-source software, in order to permit affordable reproducibility of volumes calculation.

  3. Height-diameter relationships of tropical Atlantic moist forest trees in southeastern Brazil

    OpenAIRE

    Marcos Augusto da Silva Scaranello; Luciana Ferreira Alves; Simone Aparecida Vieira; Plinio Barbosa Camargo; Carlos Alfredo Joly; Luiz Antônio Martinelli

    2013-01-01

    Site-specific height-diameter models may be used to improve biomass estimates for forest inventories where only diameter at breast height (DBH) measurements are available. In this study, we fit height-diameter models for vegetation types of a tropical Atlantic forest using field measurements of height across plots along an altitudinal gradient. To fit height-diameter models, we sampled trees by DBH class and measured tree height within 13 one-hectare permanent plots established at four altitu...

  4. Bloch-Wave Engineered Submicron Diameter Micropillars with Quality Factors Exceeding 10,000

    DEFF Research Database (Denmark)

    Hofling, S.; Lermer, M.; Gregersen, Niels;

    2011-01-01

    Adiabatic design submicron diameter quantum-dot micropillars have been designed and implemented for cavity quantum electrodynamics experiments. Ultra-high experimental quality factors (>10,000) are obtained for submicron diameters and strong light-matter interaction is observed.......Adiabatic design submicron diameter quantum-dot micropillars have been designed and implemented for cavity quantum electrodynamics experiments. Ultra-high experimental quality factors (>10,000) are obtained for submicron diameters and strong light-matter interaction is observed....

  5. Diameters and form of skull base foramen ovale measured by three-dimensional spiral CT thin-slice scan in healthy adults

    Institute of Scientific and Technical Information of China (English)

    Xiaohua Chen; Fengxian Deng; Shuhang Wei; Tingsong Fang

    2006-01-01

    BACKGROUND: The accurate measurements of various data of the bone diameters of foramen ovale of living person can change the methods of puncturing trigeminal gasserian ganglion via foramen ovale for treating trifacial neuralgia from the experience of puncture operator only to puncture by taking the objective data of measurement as the evidence, which is good for improving the accuracy of puncturing trigeminal ganglion and reducing side effects.OBJECTiVE: To observe the forms of foramen ovales in healthy adults displayed by volume rendering and multi-planar reconstruction after three-dimensional spiral CT thin-slice scan of skull base, and measure the longitudinal diameter and transverse diameter.DESTGN: A repetitive observation and measurement.SETTINGS: Department of Neurosurgery and Department of Medical Imaging, Foshan Hospital of Traditional Chinese Medicine.PARTICTPANTS: Fifty healthy adults (100 sides), who were examined with three-dimensional spiral CT scan,were randomly selected from the Department of Medical Imaging, Foshan Hospital of Traditional Chinese Medicine from January 2005 to January 2006, including 26 males and 24 females, aged 25-68 years with an average of 48 years old. They were all informed and agreed with the examination.METHODS: The subjects were examined with the Philips 16-slice spiral CT-Mx 8000 IDT CT apparatus (Philips Company, Holland), the scanning ranged from 2 cm below the canthomeatal line to the level of suprasellar cistern. The width of collimator was 0.75 mm, pitch was 0.663; tube current was 350 mA, voltage was 120 kV,resolution was 512×512 matrix; slice thickness of reconstruction was 1 mm, and interval was 0.5 mm. After the three-dimensional spiral CT thin-slice scan of skull base, the image post-processing techniques including volume rendering and multi-planar reconstruction were applied to observe the forms of foramen ovales, and measure the size, longitudinal diameter and transverse diameter of the foramen ovales. The

  6. Effect of hole geometry and Electric-Discharge Machining (EDM) on airflow rates through small diameter holes in turbine blade material

    Science.gov (United States)

    Hippensteele, S. A.; Cochran, R. P.

    1980-01-01

    The effects of two design parameters, electrode diameter and hole angle, and two machine parameters, electrode current and current-on time, on air flow rates through small-diameter (0.257 to 0.462 mm) electric-discharge-machined holes were measured. The holes were machined individually in rows of 14 each through 1.6 mm thick IN-100 strips. The data showed linear increase in air flow rate with increases in electrode cross sectional area and current-on time and little change with changes in hole angle and electrode current. The average flow-rate deviation (from the mean flow rate for a given row) decreased linearly with electrode diameter and increased with hole angle. Burn time and finished hole diameter were also measured.

  7. Experimental study on stability of sunken large diameter cylindrical structure on sandy seabed during construction period

    Institute of Scientific and Technical Information of China (English)

    秦崇仁; 庞红犁; 李世森; 张伟

    2002-01-01

    A systematic experimental research work is done for the stability of sunken large diameter cylinder during construction period. It is the first research that gives the method for assessing the stability of the larger diameter cylindrical structure, a set of values is derived also for the critical stability indices of the large diameter cylinder sunken to the sandy seabed.

  8. Comprehensive database of diameter-based biomass regressions for North American tree species

    Science.gov (United States)

    Jennifer C. Jenkins; David C. Chojnacky; Linda S. Heath; Richard A. Birdsey

    2004-01-01

    A database consisting of 2,640 equations compiled from the literature for predicting the biomass of trees and tree components from diameter measurements of species found in North America. Bibliographic information, geographic locations, diameter limits, diameter and biomass units, equation forms, statistical errors, and coefficients are provided for each equation,...

  9. Basic maneuvers for an inspection robot for small diameter gas distribution mains

    NARCIS (Netherlands)

    Dertien, Edwin Christian; Stramigioli, Stefano

    2011-01-01

    This video shows the design of a mechanical structure of a miniature pipe inspection robot (MPR) capable of moving trough very small pipes (up to 41 mm inner diameter) as well as a wide range of diameters (63 to 125 mm outer diameter). The requirement to negotiate bends, T-joints and steep

  10. Basic maneuvers for an inspection robot for small diameter gas distribution mains

    NARCIS (Netherlands)

    Dertien, Edwin; Stramigioli, Stefano

    2011-01-01

    This video shows the design of a mechanical structure of a miniature pipe inspection robot (MPR) capable of moving trough very small pipes (up to 41 mm inner diameter) as well as a wide range of diameters (63 to 125 mm outer diameter). The requirement to negotiate bends, T-joints and steep inclinati

  11. 78 FR 60897 - Certain Welded Large Diameter Line Pipe From Japan

    Science.gov (United States)

    2013-10-02

    ... COMMISSION Certain Welded Large Diameter Line Pipe From Japan Determination On the basis of the record \\1... the antidumping duty order on certain welded large diameter line pipe from Japan would likely to lead... Certain Welded Large Diameter Line Pipe from Japan: Investigation No. 731-TA-919 (Second Review). By order...

  12. Non-linear height-diameter models for oriental beech (Fagus orientalis Lipsky in the Hyrcanian forests, Iran

    Directory of Open Access Journals (Sweden)

    Ahmadi, K.

    2013-01-01

    Full Text Available The relationship between tree height and diameter is an important element in growth and yield models, in carbon budget and timber volume models, and in the description of stand dynamics. Six non-linear growth functions (i.e. Chapman-Richards, Schnute, Lundqvist/Korf, Weibull, Modified Logistic and Exponential were fitted to tree height-diameter data of oriental beech in the Hyrcanian mixed hardwood forests of Iran. The predictive performance of these models was in the first place assessed by means of different model evaluation criteria such as adjusted R squared (adjR2, root mean square error (RMSE, Akaike information criterion (AIC, mean difference (MD, mean absolute difference (MAD and mean square (MS error criteria. Although each of the six models accounted for approximately 75% of total variation in height, a large difference in asymptotic estimates was observed. Apart from this, the predictive performance of the models was also evaluated by means of cross-validation and by splitting the data into 5-cm diameter classes. Plotting the MD in relation to these diameter at breast height (DBH classes showed for all growth functions, except for the Modified Logistic function, similar mean prediction errors for small- and medium-sized trees. Large-sized trees, however, showed a higher mean prediction error. The Modified Logistic function showed the worst performance due to a large model bias. The Exponential and Lundqvist/Korf models were discarded due to their showing biologically illogical behavior and unreasonable estimates for the asymptotic coefficient, respectively. Considering all the above-mentioned criteria, the Chapman-Richards, Weibull, and Schnute functions provided the most satisfactory height predictions. However, we would recommend the Chapman-Richards function for further analysis because of its higher predictive performance.

  13. Rigidity spectrum of Forbush decrease

    Science.gov (United States)

    Sakakibara, S.; Munakata, K.; Nagashima, K.

    1985-01-01

    Using data from neutron monitors and muon telescopes at surface and underground stations, the average rigidity spectrum of Forbush decreases (Fds) during the period of 1978-1982 were obtained. Thirty eight Ed-events are classified into two groups Hard Fd and Soft Fd according to size of Fd at Sakashita station. It is found that a spectral form of fractional-power type (P to the-gamma sub 1 (P+P sub c) to the -gamma sub2) is more suitable for the present purpose than that of power-exponential type or of power type with an upper limiting rigidity. The best fitted spectrum of fractional-power type is expressed by gamma sub1 = 0.37, gamma sub2 = 0.89 and P subc = 10 GV for Hard Fd and gamma sub1 = 0.77, gamma sub2 = 1.02 and P sub c - 14GV for Soft Fd.

  14. Hyperhomocysteinemia decreases bone blood flow

    Directory of Open Access Journals (Sweden)

    Neetu T

    2011-01-01

    Full Text Available Neetu Tyagi*, Thomas P Vacek*, John T Fleming, Jonathan C Vacek, Suresh C TyagiDepartment of Physiology and Biophysics, School of Medicine, University of Louisville, Louisville, KY, USA *These authors have equal authorshipAbstract: Elevated plasma levels of homocysteine (Hcy, known as hyperhomocysteinemia (HHcy, are associated with osteoporosis. A decrease in bone blood flow is a potential cause of compromised bone mechanical properties. Therefore, we hypothesized that HHcy decreases bone blood flow and biomechanical properties. To test this hypothesis, male Sprague–Dawley rats were treated with Hcy (0.67 g/L in drinking water for 8 weeks. Age-matched rats served as controls. At the end of the treatment period, the rats were anesthetized. Blood samples were collected from experimental or control rats. Biochemical turnover markers (body weight, Hcy, vitamin B12, and folate were measured. Systolic blood pressure was measured from the right carotid artery. Tibia blood flow was measured by laser Doppler flow probe. The results indicated that Hcy levels were significantly higher in the Hcy-treated group than in control rats, whereas vitamin B12 levels were lower in the Hcy-treated group compared with control rats. There was no significant difference in folate concentration and blood pressure in Hcy-treated versus control rats. The tibial blood flow index of the control group was significantly higher (0.78 ± 0.09 flow unit compared with the Hcy-treated group (0.51 ± 0.09. The tibial mass was 1.1 ± 0.1 g in the control group and 0.9 ± 0.1 in the Hcy-treated group. The tibia bone density was unchanged in Hcy-treated rats. These results suggest that Hcy causes a reduction in bone blood flow, which contributes to compromised bone biomechanical properties.Keywords: homocysteine, tibia, bone density

  15. Effect of volume expansion on systemic hemodynamics and central and arterial blood volume in cirrhosis

    DEFF Research Database (Denmark)

    Møller, Søren; Bendtsen, Flemming; Henriksen, Jens Henrik

    1995-01-01

    and in controls. METHODS: Thirty-nine patients with cirrhosis (12 patients with Child-Turcotte class A, 14 with class B, and 13 with class C) and 6 controls were studied. During hepatic vein catheterization, cardiac output, systemic vascular resistance, central and arterial blood volume, noncentral blood volume...... in patients with either class B or class C. Conversely, the noncentral blood volume increased in patients with class B and C. In both patients and controls, the cardiac output increased and the systemic vascular resistance decreased, whereas the mean arterial blood pressure did not change significantly......BACKGROUND & AIMS: Systemic vasodilatation in cirrhosis may lead to hemodynamic alterations with reduced effective blood volume and decreased arterial blood pressure. This study investigates the response of acute volume expansion on hemodynamics and regional blood volumes in patients with cirrhosis...

  16. Forming limits under multi-index constraints in NC bending of aluminum alloy thin-walled tubes with large diameters

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    With increasing diameters of aluminum alloy thin-walled tubes (AATTs), the tube forming limits, i.e. the minimum bending factors, and their predictions under multi-index constraints including wrinkling, thinning and flattening have been being a key problem to be urgently solved for improving tube forming potential in numerical control (NC) bending processes of AATTs with large diameters. Thus in this paper, a search algorithm of the forming limits is put forward based on a 3D elastic-plastic finite element (FE) model and a wrinkling energy prediction model for the bending processes under axial compression loading (ACL) or not. This algorithm enables to be considered the effects of process parameter combinations including die, friction parameters on the multi-indices. Based on this algorithm, the forming limits of the different size tubes are obtained, and the roles of the process parameter combinations in enabling the limit bending processes are also revealed. The followings are found: the first, within the appropriate ranges of friction and clearances between the different dies and the tubes enabling the bending processes with smaller bending factors, the ACL enables the tube limit bending processes after a decrease of the mandrel ball thickness and diameters; then, without considering the effects of the tube geometry sizes on the tube constitutive equations, the forming limits will be decided by the limit thinning values for the tubes with diameters smaller than 80 mm, while the wrinkling for the tubes with diameters no less than 80 mm. The forming limits obtained from this algorithm are smaller than the analytical results, and reduced by 57.39%; the last, the roles of the process parameter combinations in enabling the limit bending processes are verified by experimental results.

  17. Effect of input power on cooling property of a thermoacoustic cooling system with diameter-expanded prime movers

    Science.gov (United States)

    Ueno, So; Sakamoto, Shin-ichi; Orino, Yuichiro; Wada, Takahiro; Inui, Yoshitaka; Watanabe, Yoshiaki

    2016-07-01

    We studied a thermoacoustic cooling system driven at low temperatures to make practical use of the system. Aiming to reduce the driving temperature of the thermoacoustic system, we developed a loop-tube-type thermoacoustic system with diameter-expanded two-stage prime movers, i.e., a heat-to-sound transducer. The system drove at 67 °C. Additionally, we developed a prototype for a thermoacoustic cooling system with a diameter-expanded two-stage prime mover. In the experiment, the cooling point temperature was decreased by 4.4 °C from room temperature, i.e., 20 °C. To improve the cooling performance of the prototype thermoacoustic cooling system, we experimentally investigated the effect of increasing the input power on the cooling performance.

  18. Study of association between ovarian volume with the number of antral follicles and third day of menstruation FSH in infertile patients referred to Omid Persian gulf infertility Clinic

    Directory of Open Access Journals (Sweden)

    Elham Rahmani

    2016-09-01

    Full Text Available Background: Ovarian reserve tests have appeared as important, useful and new tools in evaluation of infertile women and by doing these tests, we can do for infertile couples advanced and necessary measures quickly. The goal of this study was to investigate the association between ovarian volume, Antral follicle counts and serum level of FSH at the third day of menstruation. Material and Methods: This study was conducted on 78 women between 18-49 years old who referred to Omid Persian gulf infertility Clinic with complaining of infertility in 2014. In patients who had inclusion criteria, measurement of ovarian volume were done with calculation of three diameters and the number of antral follicles by using vaginal ultrasound in third day of menstruation. Also, in this patients were measured the levels of FSH&LH in third day of menstruation. Pearson correlation coefficient were used to examine the relationship between ovarian volume and the number of Antral follicles and serum levels. Results: ovarian volume and Antral follicle counts (p=0.0001 decreased and serum level of FSH (p=0.0001 and LH (p=0,022 increased significantly with increasing of age. There was a strong positive correlation between ovarian volume and Antral follicle counts (r=0.96, p=0.0001 and there was a strong reversed correlation between ovarian volume and Antral follicle counts with FSH (r=0.50, p=0.0001. Conclusion: By increasing age, ovarian volume and Antral follicle counts decreased and FSH&LH levels increased. In fact, in the initial study of infertile patients, even by diagnosis of reduction in ovarian volume and Antral follicle count should be performed advanced therapies and there is no need to wait for expensive tests result.

  19. Insular volume reduction in schizophrenia.

    Science.gov (United States)

    Saze, Teruyasu; Hirao, Kazuyuki; Namiki, Chihiro; Fukuyama, Hidenao; Hayashi, Takuji; Murai, Toshiya

    2007-12-01

    Structural and functional abnormalities of the insular cortex have been reported in patients with schizophrenia. Most studies have shown that the insular volumes in schizophrenia patients are smaller than those of healthy people. As the insular cortex is functio-anatomically divided into anterior and posterior subdivisons, recent research is focused on uncovering a specific subdivisional abnormality of the insula in patients with schizophrenia. A recent ROI-based volumetric MRI study demonstrated specific left anterior insular volume reduction in chronic schizophrenia patients (Makris N, Goldstein J, Kennedy D, Hodge S, Caviness V, Faraone S, Tsuang M, Seidman L (2006) Decreased volume of left and total anterior insular lobule in schizophrenia. Schizophr Res 83:155-171). On the other hand, our VBM-based volumetric study revealed a reduction in right posterior insular volume (Yamada M, Hirao K, Namiki C, Hanakawa T, Fukuyama H, Hayashi T, Murai T (2007) Social cognition and frontal lobe pathology in schizophrenia: a voxel-based morphometric study. NeuroImage 35:292-298). In order to address these controversial results, ROI-based subdivisional volumetry was performed using the MRI images from the same population we analyzed in our previous VBM-study. The sample group comprised 20 schizophrenia patients and 20 matched healthy controls. Patients with schizophrenia showed a global reduction in insular gray matter volumes relative to healthy comparison subjects. In a simple comparison of the volumes of each subdivision between the groups, a statistically significant volume reduction in patients with schizophrenia was demonstrated only in the right posterior insula. This study suggests that insular abnormalities in schizophrenia would include anterior as well as posterior parts. Each subdivisional abnormality may impact on different aspects of the pathophysiology and psychopathology of schizophrenia; these relationships should be the focus of future research.

  20. Experimental Investigation of Micro Heat Pipes of Different Cross-Sections Having Same Hydraulic Diameter

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Effects of micro heat pipe (MHP) cross-sections and orientations on its thermal perforrnance are experimentally investigated in this study. Tests are conducted using five different cross-sections (circular, semicircular, elliptical,semi-elliptical and rectangular) of micro heat pipes having same hydraulic diameter of 3 mm placed at three different inclination angles (0°, 45°, 90°), where water is used as the working fluid. Evaporator section of the MHP is heated by an electric heater and the condenser section is cooled by circulation of water in an annular space between condenser section and the water jacket. Temperatures at different locations of the MHP are measured using five calibrated K type thermocouples. Heat supply is varied using a voltage regulator which is measured by a precision ammeter and a voltmeter. It is found that thermal performance tends to deteriorate as the MHP is flattened.Thus among all cross-sections of MHP, circular one exhibits the best thermal performance in terms of heat flux dissipation followed by semi-elliptical, semi-circular, elliptical and rectangular cross-sections. Moreover, its heat transfer capability also decreases with decreasing of its inclination angle. Finally, a correlation is developed which covers all the experimental data within +7%.

  1. Optical investigation of gold shell enhanced 25 nm diameter upconverted fluorescence emission

    Science.gov (United States)

    Green, Kory; Wirth, Janina; Lim, Shuang Fang

    2016-04-01

    We enhance the efficiency of upconverting nanoparticles by investigating the plasmonic coupling of 25 nm diameter NaYF4:Yb, Er nanoparticles with a gold-shell coating, and study the physical mechanism of enhancement by single-particle, time-resolved spectroscopy. A three-fold overall increase in emission intensity, and five-fold increase of green emission for these plasmonically enhanced particles have been achieved. Using a combination of structural and fluorescent imaging, we demonstrate that fluorescence enhancement is based on the photonic properties of single, isolated particles. Time-resolved spectroscopy shows that the increase in fluorescence is coincident with decreased rise time, which we attribute to an enhanced absorption of infrared light and energy transfer from Yb3+ to Er3+ atoms. Time-resolved spectroscopy also shows that fluorescence life-times are decreased to different extents for red and green emission. This indicates that the rate of photon emission is not suppressed, as would be expected for a metallic cavity, but rather enhanced because the metal shell acts as an optical antenna, with differing efficiency at different wavelengths.

  2. Measurement of Vortex Strength and Core Diameter in the Wake of a Hovering Rotor

    Science.gov (United States)

    Wadcock, Alan J.

    1997-01-01

    Detailed hot wire measurements have been acquired in the tip vortex of a three-bladed model tilt rotor in hover. Testing was conducted at a rotor tip speed of 752 ft/sec, a Reynolds number (based on blade tip chord) of 1.77 x 10(exp 6), for thrust coefficients up to 0.0160. A figure shows the hot wire mounted above the inverted rotor at the Outside Aerodynamic Rotor Facility (OARF) at NASA Ames Research Center. Strobed shadowgraph flow visualization was used to define the vortex trajectory as an aid in hot wire positioning. Considerable variations in tip vortex structure with time were observed, even from the same blade, under essentially uniform test conditions. The only velocity signatures analyzed were those corresponding to passage of the probe directly through the center of the vortex. These time histories were ensemble averaged after compensating for jitter in the vortex arrival time at the probe, thereby retaining the core structure with minimal smearing. An example of a mean velocity signature, after ensemble averaging, is shown. The mean velocity signature was analyzed under the assumption of constant (unknown) translation speed of the vortex filament past the fixed probe. The translation speed of the vortex is deduced and the vortex strength and core diameter inferred. The results were highly unexpected. The indicated vortex strength is seen to decrease rapidly after first blade passage. In addition, the core radius is seen to decrease with increasing wake age, not increase as might be expected from simple diffusion.

  3. Differential effects of two indigenous broilers exposed to cold stress and characters of follicle density and diameter

    Directory of Open Access Journals (Sweden)

    Zhao Y. Geng

    2011-01-01

    Full Text Available Indigenous chickens from various part of China, due to different feather characters, always performed differently when countered with cold stress. In this study, the effects of long term hypothermia on serum hormones (triiodothyronine, thyroxine and insulin and activity of plasma enzymes (Alanine aminotransferase, aspartate aminotransferase, gamma-glutamyltransferase, creatine kinase and lactic dehydrogenase were studied in two indigenous broiler breeds, Huainan partridge (H and Wenchang (W chickens. Chickens in 20°C±2°C were compared with those subjected to moderate (15°C±2°C and severe low temperature (10°C±2°C for one week. Long-term hypothermia elevated plasma insulin and reduced T4 in W, decelerated insulin and increased T4 in H, while T3 did not change in the two breeds. Plasma enzymes AST, LDH and CK decreased in the two breeds and ALT only decreased in W exposed to cold stress. A significantly decreased body weight gain of H and no variations in W at low temperature were observed. However, a trend of decreased weight gain in W was observed when bred under low temperature condition. Follicle density and diameter were compared in the two breeds with back density in H significantly higher than W and diameter from back of H significantly smaller than W, while much larger than the latter at latero-abdominal part. We investigated the pattern of serum biological change, follicle diameter and density under cold stress condition in two indigenous broiler breeds from different areas of China to provide informative guidance for broiler production and indications in breeding of cold resistant breed.

  4. Differential effects of two indigenous broilers exposed to cold stress and characters of follicle density and diameter

    Directory of Open Access Journals (Sweden)

    Xing Y. Chen

    2011-02-01

    Full Text Available digenous chickens from various part of China, due to different feather characters, always performed differently when countered with cold stress. In this study, the effects of long term hypothermia on serum hormones (triiodothyronine, thyroxine and insulin and activity of plasma enzymes (Alanine aminotransferase, aspartate aminotransferase, gamma-glutamyltransferase, creatine kinase and lactic dehydrogenase were studied in two indigenous broiler breeds, Huainan partridge (H and Wenchang (W chickens. Chickens in 20°C±2°C were compared with those subjected to moderate (15°C±2°C and severe low temperature (10°C±2°C for one week. Long-term hypothermia elevated plasma insulin and reduced T4 in W, decelerated insulin and increased T4 in H, while T3 did not change in the two breeds. Plasma enzymes AST, LDH and CK decreased in the two breeds and ALT only decreased in W exposed to cold stress. A significantly decreased body weight gain of H and no variations in W at low temperature were observed. However, a trend of decreased weight gain in W was observed when bred under low temperature condition. Follicle density and diameter were compared in the two breeds with back density in H significantly higher than W and diameter from back of H significantly smaller than W, while much larger than the latter at latero-abdominal part. We investigated the pattern of serum biological change, follicle diameter and density under cold stress condition in two indigenous broiler breeds from different areas of China to provide informative guidance for broiler production and indications in breeding of cold resistant breed.

  5. Height-diameter allometry of tropical forest trees

    Directory of Open Access Journals (Sweden)

    T. R. Feldpausch

    2011-05-01

    Full Text Available Tropical tree height-diameter (H:D relationships may vary by forest type and region making large-scale estimates of above-ground biomass subject to bias if they ignore these differences in stem allometry. We have therefore developed a new global tropical forest database consisting of 39 955 concurrent H and D measurements encompassing 283 sites in 22 tropical countries. Utilising this database, our objectives were:

    1. to determine if H:D relationships differ by geographic region and forest type (wet to dry forests, including zones of tension where forest and savanna overlap.

    2. to ascertain if the H:D relationship is modulated by climate and/or forest structural characteristics (e.g. stand-level basal area, A.

    3. to develop H:D allometric equations and evaluate biases to reduce error in future local-to-global estimates of tropical forest biomass.

    Annual precipitation coefficient of variation (PV, dry season length (SD, and mean annual air temperature (TA emerged as key drivers of variation in H:D relationships at the pantropical and region scales. Vegetation structure also played a role with trees in forests of a high A being, on average, taller at any given D. After the effects of environment and forest structure are taken into account, two main regional groups can be identified. Forests in Asia, Africa and the Guyana Shield all have, on average, similar H:D relationships, but with trees in the forests of much of the Amazon Basin and tropical Australia typically being shorter at any given D than their counterparts elsewhere. The region-environment-structure model with the lowest Akaike's information criterion and lowest deviation estimated stand-level H across all plots to within amedian −2.7 to 0.9% of the true value. Some of the plot-to-plot variability in

  6. Height-diameter allometry of tropical forest trees

    Directory of Open Access Journals (Sweden)

    T. R. Feldpausch

    2010-10-01

    Full Text Available Tropical tree height-diameter (H:D relationships may vary by forest type and region making large-scale estimates of above-ground biomass subject to bias if they ignore these differences in stem allometry. We have therefore developed a new global tropical forest database consisting of 39 955 concurrent H and D measurements encompassing 283 sites in 22 tropical countries. Utilising this database, our objectives were:

      1. to determine if H:D relationships differ by geographic region and forest type (wet to dry forests, including zones of tension where forest and savanna overlap.

      2. to ascertain if the H:D relationship is modulated by climate and/or forest structural characteristics (e.g. stand-level basal area, A.

      3. to develop H:D allometric equations and evaluate biases to reduce error in future local-to-global estimates of tropical forest biomass.

    Annual precipitation coefficient of variation (PV, dry season length (SD, and mean annual air temperature (TA emerged as key drivers of variation in H:D relationships at the pantropical and region scales. Vegetation structure also played a role with trees in forests of a high A being, on average, taller at any given D. After the effects of environment and forest structure are taken into account, two main regional groups can be identified. Forests in Asia, Africa and the Guyana Shield all have, on average, similar H:D relationships, but with trees in the forests of much of the Amazon Basin and tropical Australia typically being shorter at any given D than their counterparts elsewhere.

    The region-environment-structure model with the lowest Akaike's information criterion and lowest deviation estimated stand-level H across all plots to within a median –2.7 to 0.9% of the true value. Some of the plot

  7. Control of the Diameter and Chiral Angle Distributions during Production of Single-Wall Carbon Nanotubes

    Science.gov (United States)

    Nikolaev, Pavel

    2009-01-01

    Many applications of single wall carbon nanotubes (SWCNT), especially in microelectronics, will benefit from use of certain (n,m) nanotube types (metallic, small gap semiconductor, etc.) Especially fascinating is the possibility of quantum conductors that require metallic armchair nanotubes. However, as produced SWCNT samples are polydisperse, with many (n,m) types present and typical approx.1:2 metal/semiconductor ratio. Nanotube nucleation models predict that armchair nuclei are energetically preferential due to formation of partial triple bonds along the armchair edge. However, nuclei can not reach any meaningful thermal equilibrium in a rapidly expanding and cooling plume of carbon clusters, leading to polydispersity. In the present work, SWCNTs were produced by a pulsed laser vaporization (PLV) technique. The carbon vapor plume cooling rate was either increased by change in the oven temperature (expansion into colder gas), or decreased via "warm-up" with a laser pulse at the moment of nucleation. The effect of oven temperature and "warm-up" on nanotube type population was studied via photoluminescence, UV-Vis-NIR absorption and Raman spectroscopy. It was found that reduced temperatures leads to smaller average diameters, progressively narrower diameter distributions, and some preference toward armchair structures. "Warm-up" shifts nanotube population towards arm-chair structures as well, but the effect is small. Possible improvement of the "warm-up" approach to produce armchair SWCNTs will be discussed. These results demonstrate that PLV production technique can provide at least partial control over the nanotube (n,m) population. In addition, these results have implications for the understanding the nanotube nucleation mechanism in the laser oven.

  8. Increased response to glutamate in small diameter dorsal root ganglion neurons after sciatic nerve injury.

    Directory of Open Access Journals (Sweden)

    Kerui Gong

    Full Text Available Glutamate in the peripheral nervous system is involved in neuropathic pain, yet we know little how nerve injury alters responses to this neurotransmitter in primary sensory neurons. We recorded neuronal responses from the ex-vivo preparations of the dorsal root ganglia (DRG one week following a chronic constriction injury (CCI of the sciatic nerve in adult rats. We found that small diameter DRG neurons (30 µm were unaffected. Puff application of either glutamate, or the selective ionotropic glutamate receptor agonists alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA and kainic acid (KA, or the group I metabotropic receptor (mGluR agonist (S-3,5-dihydroxyphenylglycine (DHPG, induced larger inward currents in CCI DRGs compared to those from uninjured rats. N-methyl-D-aspartate (NMDA-induced currents were unchanged. In addition to larger inward currents following CCI, a greater number of neurons responded to glutamate, AMPA, NMDA, and DHPG, but not to KA. Western blot analysis of the DRGs revealed that CCI resulted in a 35% increase in GluA1 and a 60% decrease in GluA2, the AMPA receptor subunits, compared to uninjured controls. mGluR1 receptor expression increased by 60% in the membrane fraction, whereas mGluR5 receptor subunit expression remained unchanged after CCI. These results show that following nerve injury, small diameter DRG neurons, many of which are nociceptive, have increased excitability and an increased response to glutamate that is associated with changes in receptor expression at the neuronal membrane. Our findings provide further evidence that glutamatergic transmission in the periphery plays a role in nociception.

  9. FEASIBILITY STUDY OF BUSINESS IN AGARWOOD INOCULATION AT DIFFERENT STEM DIAMETERS AND INOCULATION PERIODS

    Directory of Open Access Journals (Sweden)

    Sri Suharti

    2011-12-01

    Full Text Available Indonesia signifies as the biggest agarwood producer country in the world. Its demand and price tend to increase and have brought about over exploitation of agarwood. Consequently, its population in nature has decreased significantly. To overcome the situation, since 1995, agarwood has been included in the CITES Appendix II. However, illegal exploitation remains persistent and reaches an excessive level. In order to deal with it, agarwood cultivation and its artificial production have been undertaken at several provinces in Indonesia. Some supporting factors for agarwood cultivation and artificial production are the availability of potential land for extensive cultivation, appropriate agro climate condition, simple cultivation technique and already being well adopted by farmers, the availability of necessary pathogen for agarwood inoculation, and the increasing demand with relatively high price. The research aims to analyze the feasibility study of agarwood inoculation business at several stem diameters (15 - 25 cm; 26 -35 cm and 36 - 40 cm and periods of inoculation (1 - 5 years. Data were collected through field observation and literature study. The results showed that inoculation on agarwood producer tree stands at 12.5% interest rate afforded positive net present value (NPV,  internal rate of return (IRR is much higher than market interest and benefit cost (B/C ratio >2 for those three diameter classes. Furthermore, if agarwood harvesting is delayed until five years after inoculation, NPV,  IRR and B/C ratio would be much higher. It can be concluded that inoculation on agarwood producer tree stands (at appropriate age for inoculation is feasible to be developed.

  10. Selective control of small versus large diameter axons using infrared laser light (Conference Presentation)

    Science.gov (United States)

    Lothet, Emilie H.; Shaw, Kendrick M.; Horn, Charles C.; Lu, Hui; Wang, Yves T.; Jansen, E. Duco; Chiel, Hillel J.; Jenkins, Michael W.

    2016-03-01

    Sensory information is conveyed to the central nervous system via small diameter unmyelinated fibers. In general, smaller diameter axons have slower conduction velocities. Selective control of such fibers could create new clinical treatments for chronic pain, nausea in response to chemo-therapeutic agents, or hypertension. Electrical stimulation can control axonal activity, but induced axonal current is proportional to cross-sectional area, so that large diameter fibers are affected first. Physiologically, however, synaptic inputs generally affect small diameter fibers before large diameter fibers (the size principle). A more physiological modality that first affected small diameter fibers could have fewer side effects (e.g., not recruiting motor axons). A novel mathematical analysis of the cable equation demonstrates that the minimum length along the axon for inducing block scales with the square root of axon diameter. This implies that the minimum length along an axon for inhibition will scale as the square root of axon diameter, so that lower radiant exposures of infrared light will selectively affect small diameter, slower conducting fibers before those of large diameter. This prediction was tested in identified neurons from the marine mollusk Aplysia californica. Radiant exposure to block a neuron with a slower conduction velocity (B43) was consistently lower than that needed to block a faster conduction velocity neuron (B3). Furthermore, in the vagus nerve of the musk shrew, lower radiant exposure blocked slow conducting fibers before blocking faster conducting fibers. Infrared light can selectively control smaller diameter fibers, suggesting many novel clinical treatments.

  11. Pseudomagnitudes and differential surface brightness: Application to the apparent diameter of stars

    Science.gov (United States)

    Chelli, Alain; Duvert, Gilles; Bourgès, Laurent; Mella, Guillaume; Lafrasse, Sylvain; Bonneau, Daniel; Chesneau, Olivier

    2016-05-01

    The diameter of a star is a major observable that serves to test the validity of stellar structure theories. It is also a difficult observable that is mostly obtained with indirect methods since the stars are so remote. Today only ~600 apparent star diameters have been measured by direct methods: optical interferometry and lunar occultations. Accurate star diameters are now required in the new field of exoplanet studies, since they condition the planets' sizes in transit observations, and recent publications illustrate a visible renewal of interest in this topic. Our analysis is based on the modeling of the relationship between measured angular diameters and photometries. It makes use of two new reddening-free concepts: a distance indicator called pseudomagnitude, and a quasi-experimental observable that is independent of distance and specific to each star, called the differential surface brightness (DSB). The use of all the published measurements of apparent diameters that have been collected so far, and a careful modeling of the DSB allow us to estimate star diameters with a median statistical error of 1.1%, knowing their spectral type and, in the present case, the VJHKs photometries. We introduce two catalogs, the JMMC Measured Diameters Catalog (JMDC), containing measured star diameters, and the second version of the JMMC Stellar Diameter Catalog (JSDC), augmented to about 453 000 star diameters. Finally, we provide simple formulas and a table of coefficients to quickly estimate stellar angular diameters and associated errors from (V, Ks) magnitudes and spectral types.

  12. Diameter Tuning of Single Walled Carbon Nanotubes with Reaction Temperature Using a Co Monometallic Catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Li, N.; Wang, X; Ren, F; Haller, G; Pfefferle, L

    2009-01-01

    Metal incorporated MCM-41 has proven to be a valuable template for the growth of narrow distributions of single-walled carbon nanotubes (SWNT), producing samples with a wide range of different mean diameters. The ability to obtain narrow diameter distributions at different mean diameters is important for applications that require particular (n,m) nanotubes. Another advantage of this system is the ease of cleaning and low metal content as compared to bimetallic systems. In this Article, we show that Co-MCM-41 allows diameter tuning of SWNT produced over a broad diameter range (from 0.6-0.8 to 1.8-2.0 nm) by changing reaction temperature. The lower temperature reaction provides a robust means to obtain very small diameter SWNT. X-ray absorption experiments show that the change in SWNT diameter correlates with the change in metal particle size.

  13. 长白山云冷杉针阔混交林最优直径结构的构建%Optimal Diameter Structure for Spruce-fir Conifer and Broadleaf Mixed Stands in Changbai Mountains

    Institute of Scientific and Technical Information of China (English)

    孔雷; 亢新刚; 刘书剑; 胡云云; 黄新峰; 冯启祥

    2013-01-01

    The study was conducted on the basis of 274 permanent plots of the spruce-fir conifer and broadleaf mixed forests in Changbai Mountain,and each tree in the plots was measured.From 1987 to now,the diameters at breast heights were investigated every two years.The relationship between basal areas at breast height per hectare and stand volume per hectare was analyzed by using different kinds of models,and the mixed basal area at breast height per hectare was obtained.Simultaneously,the basal areas at breast height per hectare were divided into four intervals,< 10 m2/hm2,10-20 m2/hm2,30-40 m2/hm2 and 40-50 m2/hm2,to investigate the stand volume growths.The results showed:Stand advanced rate and tree mortality rate decrease with the increasing of the basal area intervals at breast height.The stand volume growth firstly increases,and then decreases with the increasing of basal area intervals at breast height.The mixed basal area at breast height in the region is approximately 60 m2/hm2.However,when the basal area at breast height is 40 m2/hm2 and the mean Q value is 1.4,the stand volume growth value is the highest (10.5 m3/(hm2 · year)).The optimal diameter structure distribution was modeled by negative exponential distribution model and the growth transition of diameter grade advanced rate.%以长白山云冷杉针阔混交林两个大区内274个固定样点为研究对象,样地内每木检尺;从1987年至今,每两年复查一次.利用不同模型拟合该地区林分每公顷胸高断面积和每公顷蓄积的关系,求得林分能够生长达到的每公顷最大胸高断面积,并以此为界将现有林分胸高断面积分成<10、10~20、30~40、40 ~50 m2/hm24个胸高断面积区间,分别计算各胸高断面积蓄积生长量.结果表明:林分进阶率和枯损率随胸高断面积的增加而减少;林分蓄积生长量随胸高断面积增加而先增大后减少.林分能够生长达到的最大胸高断面积大约为60 m2/hm2,但

  14. Polyhydroxybutyrate/valerate/polycaprolactone small-diameter vascular graft: Experimental study of integration into organism

    Energy Technology Data Exchange (ETDEWEB)

    Antonova, L. V., E-mail: antonova.la@mail.ru; Burago, A. Yu.; Matveeva, V. G.; Velikanova, E. A.; Mukhamadiyarov, R. A.; Glushkova, T. V.; Kudryavtseva, Y. A.; Barbarash, O. L.; Barbarash, L. S. [Research Institute for Complex Issues of Cardiovascular Diseases, Kemerovo (Russian Federation); Mironov, A. V. [Kemerovo Cardiology Dispensary, Kemerovo (Russian Federation)

    2015-10-27

    We prepared polyhydroxybutyrate/valerate (PHBV)/polylcaprolactone (PCL) small-diameter vascular grafts using electrospinning. Surface structure was assessed by scanning electron microscopy whilst physicomechanical properties were investigated by longitudinal uniaxial tension testing. Patency of grafts implanted into the rat abdominal aorta was evaluated using a Doppler ultrasonography at 2 week, 1 month and 12 month postimplantation. In addition, we assessed local histological features, along with IL-1β, IL-2, IL-4, IL-10, TNFa, TGF-β1, and VEGF serum levels. We revealed that only 2 (25%) grafts were not thrombosed at 2 week and 1 month postimplantation. However, at 12 month postimplantation a satisfactory histological pattern was observed in 50% of all cases, and we detected a monolayer of endothelial cells on the inner graft surface in half the cases. Regarding other grafts, we revealed minor connective tissue hyperplasia in 41.7% of the grafts and an inflammatory infiltrate in the part of the arterial wall in 8.3% of the grafts. We found that the IL-1β serum level was 3.5-fold higher in the group of experimental rats at 12 month postimplantation (p < 0.01). In addition, the IL-2 and IL-4 serum levels at 12 month postimplantation were 2- and 2.8-fold higher as compared to short-term implantation (2 weeks and 1 month) and control rats (p < 0.05) whilst the IL-10 serum level at 1 and 12 month postimplantation was more than 100-fold higher in comparison with 2 week postimplantation and control rats (p < 0.001). Serum VEGF was detected only at 12 month postimplantation. All in all, we created a biocompatible PHBV/PCL small-diameter vascular graft with a high surface area to volume ratio. A long-term patency of biodegradable vascular grafts after implantation into the rat abdominal aorta and the absence of a considerable immune response confirmed a high biocompatibility of such construct and the possibility of its use as a vascular graft.

  15. Polyhydroxybutyrate/valerate/polycaprolactone small-diameter vascular graft: Experimental study of integration into organism

    Science.gov (United States)

    Antonova, L. V.; Burago, A. Yu.; Mironov, A. V.; Matveeva, V. G.; Velikanova, E. A.; Mukhamadiyarov, R. A.; Glushkova, T. V.; Kudryavtseva, Y. A.; Barbarash, O. L.; Barbarash, L. S.

    2015-10-01

    We prepared polyhydroxybutyrate/valerate (PHBV)/polylcaprolactone (PCL) small-diameter vascular grafts using electrospinning. Surface structure was assessed by scanning electron microscopy whilst physicomechanical properties were investigated by longitudinal uniaxial tension testing. Patency of grafts implanted into the rat abdominal aorta was evaluated using a Doppler ultrasonography at 2 week, 1 month and 12 month postimplantation. In addition, we assessed local histological features, along with IL-1β, IL-2, IL-4, IL-10, TNFa, TGF-β1, and VEGF serum levels. We revealed that only 2 (25%) grafts were not thrombosed at 2 week and 1 month postimplantation. However, at 12 month postimplantation a satisfactory histological pattern was observed in 50% of all cases, and we detected a monolayer of endothelial cells on the inner graft surface in half the cases. Regarding other grafts, we revealed minor connective tissue hyperplasia in 41.7% of the grafts and an inflammatory infiltrate in the part of the arterial wall in 8.3% of the grafts. We found that the IL-1β serum level was 3.5-fold higher in the group of experimental rats at 12 month postimplantation (p < 0.01). In addition, the IL-2 and IL-4 serum levels at 12 month postimplantation were 2- and 2.8-fold higher as compared to short-term implantation (2 weeks and 1 month) and control rats (p < 0.05) whilst the IL-10 serum level at 1 and 12 month postimplantation was more than 100-fold higher in comparison with 2 week postimplantation and control rats (p < 0.001). Serum VEGF was detected only at 12 month postimplantation. All in all, we created a biocompatible PHBV/PCL small-diameter vascular graft with a high surface area to volume ratio. A long-term patency of biodegradable vascular grafts after implantation into the rat abdominal aorta and the absence of a considerable immune response confirmed a high biocompatibility of such construct and the possibility of its use as a vascular graft.

  16. Forest haulage of longwood and small-diameter whole trees using an agricultural tractor; Rangan ja pienkokopuun metsaekuljetus maataloustraktorilla

    Energy Technology Data Exchange (ETDEWEB)

    Ihonen, M

    1998-07-01

    The TTS Institute's Forestry Department conducted a work study on the forest haulage of delimbed and non-delimbed small-diameter wood intended for energy generation. The study was a part of the TTS Institute's research project titled 'The Energy-wood Harvesting Techniques Used by Forest Owners' (1996-98). The research project belongs to the Bioenergy Research Programme. When hauling fuelwood longwood, the agricultural tractor used was a Massey-Ferguson 575 equipped with a KO-PA 3000 hydraulic crane with a maximum reach of 6 m. The crane was mounted on the shaft of the trailer. The bogie trailer was a home-made one. The length of the wood hauled was 4-4.5 m and the load size was 3.9 m{sup 3}. The volume of wood accumulated was 7.8 m{sup 3} per 100 m of strip road. On the site where small-diameter whole trees were harvested, the agricultural tractor used was a Valmet 6600. The hydraulic crane was a Kronos 4000 with a maximum reach of 6.5 m. The crane was mounted on the tractor's 3-point linkage. The bogie trailer used was a home-made one. The length of the wood hauled was 5-6 m and the load size was 3.3 m{sup 3}. The volume of wood accumulated was 4.4 m{sup 3} per 100 m of strip road. The productivity of forest haulage of fuelwood longwood was 6.1-7.4 m{sup 3} per effective hour with the haulage distance varying between 100 and 400 m. The productivity of forest haulage of small-diameter whole trees over the same haulage distance was 4.1-5.4 m{sup 3} per effective hour. Forest transport of fuelwood longwood cost FIM 19-23 per m{sup 3} and that of small-diameter whole trees FIM 27-35 per m{sup 3}, while the cost per operating hour of the machine combination was FIM 125. The examined machine combinations were well suited for forest haulage. Productivity can be improved by extending the size of the load space, for instance. The cheapest way of achieving this is by extending the length of the bolsters by means of steel pipes. This is advantageous

  17. Forest haulage of longwood and small-diameter whole trees using and agricultural tractor; Rangan ja pienkokopuun metsaekuljetus maataloustraktorilla

    Energy Technology Data Exchange (ETDEWEB)

    Ihonen, M.

    1998-12-31

    The Forestry Dept. of the TTS Institute conducted a work study on the forest haulage of delimbed and non-delimbed small-diameter wood intended for energy generation. The study was a part of the TTS Institute`s research project titled `The energy-wood harvesting techniques used by forest owners` (1996-1998). The project is a part of the national Bioenergy Research Programme. When hauling fuel longwood, the agricultural tractor used was a Massey-Ferguson 575 equipped with a KO-PA 3000 hydraulic crane with maximum reach of 6 m. The crane was mounted on the shaft of the trailer. The bogie trailer was a home-made one. The length of the wood hauled was 4.0-4.5 m and the load size 3.9 m{sup 3}. The volume of wood accumulated was 7.8 m{sup 3} per 100 m of strip road. On the side where small-diameter whole trees were harvested, the agricultural tractor used was a Valmet 6600. The hydraulic crane was a Kronos 4000 with a maximum reach of 6.5 m. The crane was mounted on the tractor`s 3-point linkage. The bogie trailer used was a home made one. The length of the wood hauled was 5.0-6.0 m and the load size was 3.3 m{sup 3}. The volume of wood accumulated was 4.4 m{sup 3} per 100 m of strip road. The productivity of forest haulage of fuel longwood was 6.1-7.4 m{sup 3} per effective hour with the haulage distance varying between 100 and 400 m. The productivity of forest haulage of small-diameter whole trees over the same haulage distance was 4.1-5.4 m{sup 3} per effective hour. Forest transport of fuel longwood cost 19-23 FIM/M{sup 3}, and that of small-diameter whole trees 27-35 FIM/m{sup 3}, while the cost per operating hours of the machine combination was 125 FIM. The examined machine combinations were well suited for forest haulage. Productivity can be improved e.g. by extending the size of the load space. The cheapest way to achieving this is by extending the length of the bolsters by the means of steel pipes. This is advantageous especially when hauling non-delimbed wood 5

  18. Forest haulage of longwood and small-diameter whole trees using an agricultural tractor; Rangan ja pienkokopuun metsaekuljetus maataloustraktorilla

    Energy Technology Data Exchange (ETDEWEB)

    Ihonen, M.

    1998-12-31

    The TTS Institute`s Forestry Department conducted a work study on the forest haulage of delimbed and non-delimbed small-diameter wood intended for energy generation. The study was a part of the TTS Institute`s research project titled `The Energy-wood Harvesting Techniques Used by Forest Owners` (1996-98). The research project belongs to the Bioenergy Research Programme. When hauling fuelwood longwood, the agricultural tractor used was a Massey-Ferguson 575 equipped with a KO-PA 3000 hydraulic crane with a maximum reach of 6 m. The crane was mounted on the shaft of the trailer. The bogie trailer was a home-made one. The length of the wood hauled was 4-4.5 m and the load size was 3.9 m{sup 3}. The volume of wood accumulated was 7.8 m{sup 3} per 100 m of strip road. On the site where small-diameter whole trees were harvested, the agricultural tractor used was a Valmet 6600. The hydraulic crane was a Kronos 4000 with a maximum reach of 6.5 m. The crane was mounted on the tractor`s 3-point linkage. The bogie trailer used was a home-made one. The length of the wood hauled was 5-6 m and the load size was 3.3 m{sup 3}. The volume of wood accumulated was 4.4 m{sup 3} per 100 m of strip road. The productivity of forest haulage of fuelwood longwood was 6.1-7.4 m{sup 3} per effective hour with the haulage distance varying between 100 and 400 m. The productivity of forest haulage of small-diameter whole trees over the same haulage distance was 4.1-5.4 m{sup 3} per effective hour. Forest transport of fuelwood longwood cost FIM 19-23 per m{sup 3} and that of small-diameter whole trees FIM 27-35 per m{sup 3}, while the cost per operating hour of the machine combination was FIM 125. The examined machine combinations were well suited for forest haulage. Productivity can be improved by extending the size of the load space, for instance. The cheapest way of achieving this is by extending the length of the bolsters by means of steel pipes. This is advantageous especially when hauling

  19. Ovarian volume throughout life

    DEFF Research Database (Denmark)

    Kelsey, Thomas W; Dodwell, Sarah K; Wilkinson, A Graham

    2013-01-01

    cancer. To date there is no normative model of ovarian volume throughout life. By searching the published literature for ovarian volume in healthy females, and using our own data from multiple sources (combined n=59,994) we have generated and robustly validated the first model of ovarian volume from...... to about 2.8 mL (95% CI 2.7-2.9 mL) at the menopause and smaller volumes thereafter. Our model allows us to generate normal values and ranges for ovarian volume throughout life. This is the first validated normative model of ovarian volume from conception to old age; it will be of use in the diagnosis...

  20. Obesity Decreases Perioperative Tissue Oxygenation

    Science.gov (United States)

    Kabon, Barbara; Nagele, Angelika; Reddy, Dayakar; Eagon, Chris; Fleshman, James W.; Sessler, Daniel I.; Kurz, Andrea

    2005-01-01

    Background: Obesity is an important risk factor for surgical site infections. The incidence of surgical wound infections is directly related to tissue perfusion and oxygenation. Fat tissue mass expands without a concomitant increase in blood flow per cell, which might result in a relative hypoperfusion with decreased tissue oxygenation. Consequently, we tested the hypotheses that perioperative tissue oxygen tension is reduced in obese surgical patients. Furthermore, we compared the effect of supplemental oxygen administration on tissue oxygenation in obese and non-obese patients. Methods: Forty-six patients undergoing major abdominal surgery were assigned to one of two groups according to their body mass index (BMI): BMI < 30 kg/m2 (non-obese) and BMI ≥ 30 kg/m2 (obese). Intraoperative oxygen administration was adjusted to arterial oxygen tensions of ≈150 mmHg and ≈300 mmHg in random order. Anesthesia technique and perioperative fluid management were standardized. Subcutaneous tissue oxygen tension was measured with a polarographic electrode positioned within a subcutaneous tonometer in the lateral upper arm during surgery, in the recovery room, and on the first postoperative day. Postoperative tissue oxygen was also measured adjacent to the wound. Data were compared with unpaired two tailed t-tests and Wilcoxon rank-sum tests; P < 0.05 was considered statistically significant. Results: Intraoperative subcutaneous tissue oxygen tension was significantly less in the obese patients at baseline (36 vs. 57 mmHg, P = 0.002) and with supplemental oxygen administration (47 vs. 76 mmHg, P = 0.014). Immediate postoperative tissue oxygen tension was also significantly less in subcutaneous tissue of the upper arm (43 vs. 54 mmHg, P = 0.011) as well as near the incision (42 vs. 62 mmHg, P = 0.012) in obese patients. In contrast, tissue oxygen tension was comparable in each group on the first postoperative morning. Conclusion: Wound and tissue hypoxia were common in obese

  1. Study on diesel combustion with high-pressure fuel injection. Improvement of combustion and exhaust emissions using small-hole-diameter nozzles; Koatsu funsha diesel kikan no nensho kaiseki. Shofunkokei nozzle ni yoru nensho haiki kaizen koka

    Energy Technology Data Exchange (ETDEWEB)

    Nakakita, K.; Kondo, T. [Toyota Central Research and Development Labs., Inc., Aichi (Japan); Watanabe, S. [Toyota Motor Corp., Aichi (Japan)

    1994-09-25

    This paper discusses the relationship between exhaust and combustion characteristics of small-hole-diameter nozzles in diesel engines and the reduction of the hole diameter. The combustion chambers used are of deep tray type and shallow tray type. The paper describes the result when using the deep tray chamber as follows: reduced hole diameter prolongs the injection period and reduces the average injection rate; amount of exhaust NOx depends only on injection pressures, but not on the hole diameters; this is because the combustion rate increasing effect as a result of the accelerated gas mixture forming and combustion due to the hole diameter reduction is offset by the combustion rate suppressing effect due to reduced average injection rate; the hole diameter reduction presents smoke reducing effect; with a large-diameter nozzle, the smoke increases in association with reduction in the injection pressure, but with the small-diameter nozzle, low smoke emission is maintained regardless of the injection pressures, and the NOx emission can be suppressed even with an injection pressure of 55 MPa. With the shallow tray type combustion chamber, the smoke increases as the injection pressure is decreased irrespective of the nozzle hole diameter sizes, indicating a correlation between the smoke amount and the injection period. A nozzle with small diameter hole of the deep tray type is more advantageous in reducing NOx and particulate emission. 10 refs., 14 figs., 1 tab.

  2. Influence of pellet diameter and length on the quality of pellets and performance, nutrient utilisation and digestive tract development of broilers fed on wheat-based diets.

    Science.gov (United States)

    Abdollahi, M R; Ravindran, V; Wester, T J; Ravindran, G; Thomas, D V

    2013-06-01

    1. The influence of pellet diameter and length on the quality of pellets and performance, nutrient utilisation and digestive tract development of broilers given wheat-based diets was examined from 10 to 42 d of age. The experimental design was a 2 × 2 factorial arrangement of treatments evaluating two pellet diameters (3 and 4.76 mm) and two pellet lengths (3 and 6 mm). From 0 to 9 d of age, all birds were offered a common starter diet pelleted with a 3-mm diameter die and 3-mm length. Broiler grower (d 10 to 21) and finisher (d 22 to 42) diets, based on wheat, were formulated and then subjected to the 4 different treatments. 2. In grower diets, increasing pellet diameter and pellet length reduced the gelatinised starch (GS) content of the diets. In finisher diets, GS content of 3-mm diameter pellets did not change with increasing pellet length but decreased in 4.76-mm diameter pellets. 3. In grower and finisher diets, increments in intact pellet weight, pellet durability index and pellet hardness with increasing pellet length were greater in 3-mm diameter pellets than those with 4.76-mm diameter. 4. Increasing pellet length from 3 to 6 mm increased apparent metabolisable energy values. Neither the interaction nor main effects were significant for the ileal digestibility of nitrogen and starch. 5. During the grower period (d 10 to 21), birds given pellets of 6-mm length had greater body-weight gain than those given 3-mm length pellets. Feeding 6-mm length pellets decreased feed per body-weight gain compared to 3-mm length pellets. During the finisher (d 22 to 42) and whole grow-out (d 10 to 42) periods, while different pellet lengths had no effect on feed per body-weight gain values at 3-mm pellet diameter, increasing the pellet length decreased feed per body-weight gain at 4.76-mm pellet diameter. 6. Increasing pellet diameter and pellet length reduced the relative length of duodenum. Birds given 3-mm diameter pellets had heavier proventriculus compared to

  3. Polyethylene Glycol (PEG-Treated Hydroponic Culture Reduces Length and Diameter of Root Hairs of Wheat Varieties

    Directory of Open Access Journals (Sweden)

    Arif Hasan Khan Robin

    2015-10-01

    Full Text Available Wheat is an important cereal crop worldwide that often suffers from moisture deficits at the reproductive stage. Polyethylene glycol (PEG-treated hydroponic conditions create negative osmotic potential which is compared with moisture deficit stress. An experiment was conducted in a growth chamber to study the effects of PEG on root hair morphology and associated traits of wheat varieties. Plants of 13 wheat varieties were grown hydroponically and three different doses of PEG 6000 (w/v: 0% (control, 0.3% and 0.6% (less than −1 bar were imposed on 60 days after sowing for 20 days’ duration. A low PEG concentration was imposed to observe how initial low moisture stress might affect root hair development. PEG-treated hydroponic culture significantly decreased root hair diameter and length. Estimated surface area reduction of root hairs at the main axes of wheat plants was around nine times at the 0.6% PEG level compared to the control plants. Decrease in root hair diameter and length under PEG-induced culture decreased “potential” root surface area per unit length of main root axis. A negative association between panicle traits, length and dry weight and the main axis length of young roots indicated competition for carbon during their development. Data provides insight into how a low PEG level might alter root hair development.

  4. Influence of screw length and diameter on tibial strain energy density distribution after anterior cruciate ligament reconstruction

    Science.gov (United States)

    Yao, Jie; Kuang, Guan-Ming; Wong, Duo Wai-Chi; Niu, Wen-Xin; Zhang, Ming; Fan, Yu-Bo

    2014-04-01

    Postoperative tunnel enlargement has been frequently reported after anterior cruciate ligament (ACL) reconstruction. Interference screw, as a surgical implant in ACL reconstruction, may influence natural loading transmission and contribute to tunnel enlargement. The aims of this study are (1) to quantify the alteration of strain energy den sity (SED) distribution after the anatomic single-bundle ACL reconstruction; and (2) to characterize the influence of screw length and diameter on the degree of the SED alteration. A validated finite element model of human knee joint was used. The screw length ranging from 20 to 30mm with screw diameter ranging from 7 to 9 mm were investigated. In the post-operative knee, the SED increased steeply at the extra-articular tunnel aperture under compressive and complex loadings, whereas the SED decreased beneath the screw shaft and nearby the intra-articular tunnel aperture. Increasing the screw length could lower the SED deprivation in the proximal part of the bone tunnel; whereas increasing either screw length or diameter could aggravate the SED deprivation in the distal part of the bone tunnel. Decreasing the elastic modulus of the screw could lower the bone SED deprivation around the screw. In consideration of both graft stability and SED alteration, a biodegradable interference screw with a long length is recommended, which could provide a beneficial mechanical environment at the distal part of the tunnel, and meanwhile decrease the bone-graft motion and synovial fluid propagation at the proximal part of the tunnel. These findings together with the clinical and histological factors could help to improve surgical outcome, and serve as a preliminary knowledge for the following study of biodegradable interference screw. [Figure not available: see fulltext.

  5. Mean nuclear volume

    DEFF Research Database (Denmark)

    Mogensen, O.; Sørensen, Flemming Brandt; Bichel, P.

    1999-01-01

    We evaluated the following nine parameters with respect to their prognostic value in females with endometrial cancer: four stereologic parameters [mean nuclear volume (MNV), nuclear volume fraction, nuclear index and mitotic index], the immunohistochemical expression of cancer antigen (CA125...

  6. Comparison of medical of volume measurement of the prostate by transrectal ultrasound: Experiment with jelly models

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jeong Yeon; Lee, Hak Jong; Kim, Sung Hyun [Samsung Seoul Hospital, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Kim, Seung Hyup [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2002-03-15

    To evaluate the accuracy of measuring the volume of the prostate using the prolate ellipsoid volume calculation method (antero-posterior (AP) diameter X length X width X {pi}6) when the antero-posterior diameter of the prostate was measured on midsagittal (sagittal volume) and axial plane (axial volume).The devil's tongue jelly was used for the creation of ultrasound model of the prostate (volume: 15-40 cc) by cutting and shaping the surface. The volume in 10 prostatic models and 30 patients was measured and calculated. First, the AP diameter and length of the prostate models in midsagittal plane, and the height and width of the models in axial plane were measured for 3 times. The volume was calculated in two ways, one using the AP diameter an midsagittal plane and the other using the AP diameter in axial plane. The true volume of the model was measured using mess cylinder. The calculated volume and true volume were compared, and the accuracy of two method of measuring the prostatic volume was evaluated by Friedman test. The intraobserver variation was evaluated by General Linear Model, Repeated Measure. The reproducibility was evaluated by Cronbach's {alpha}. In vivo study was also performed in 30 patients. The prostate volume was calculated in the same manner. These volume data were analyzed by statistical method, and the intraobeserver variation was evaluated. While there was a statistically significant difference between the sagittal and true volume of the models, there was no statistical significant difference between the axial and true volumes. There was no significant intraobserver variation between both methods. The reproducibility was high in both methods with Cronbach's {alpha} of 0.977 and 0.942. The sagittal volume was larger than the axial volume in 30 patients with a statistically significant difference. There was no significant intraobserver variation in both methods. The reproducibility was high in both methods Cronbach's {alpha

  7. Quantification of sauter mean diameter in diesel sprays using scattering-absorption extinction measurements

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Gabrielle L; Magnotti, Gina M; Knox, Benjamin W; Genzale, Caroline L; Matusik, Katarzyna E; Duke, Daniel J; Powell, Christopher F; Kastengren, Alan L

    2017-05-18

    Quantitative measurements of the primary breakup process in diesel sprays are lacking due to a range of experimental and diagnostic challenges, including: high droplet number density environments, very small characteristic drop size scales (~1-10 μm), and high characteristic velocities in the primary breakup region (~600 m/s). Due to these challenges, existing measurement techniques have failed to resolve a sufficient range of the temporal and spatial scales involved and much remains unknown about the primary atomization process in practical diesel sprays. To gain a better insight into this process, we have developed a joint visible and x-ray extinction measurement technique to quantify axial and radial distributions of the path-integrated Sauter Mean Diameter (SMD) and Liquid Volume Fraction (LVF) for diesel-like sprays. This technique enables measurement of the SMD in regions of moderate droplet number density, enabling construction of the temporal history of drop size development within practical diesel sprays. The experimental campaign was conducted jointly at the Georgia Institute of Technology and Argonne National Laboratory using the Engine Combustion Network “Spray D” injector. X-ray radiography liquid absorption measurements, conducted at the Advanced Photon Source at Argonne, quantify the liquid-fuel mass and volume distribution in the spray. Diffused back-illumination liquid scattering measurements were conducted at Georgia Tech to quantify the optical thickness throughout the spray. By application of Mie-scatter equations, the ratio of the absorption and scattering extinction measurements is demonstrated to yield solutions for the SMD. This work introduces the newly developed scattering-absorption measurement technique and highlights the important considerations that must be taken into account when jointly processing these measurements to extract the SMD. These considerations include co-alignment of measurements taken at different institutions

  8. Influence of Nonionic Surfactant Addition on Drag Reduction of Water Based Nanofluid in a Small Diameter Pipe

    Institute of Scientific and Technical Information of China (English)

    Micha(l) Drzazga; Andrzej Gierczycki; Grzegorz Dzido; Marcin Lemanowicz

    2013-01-01

    The goal of this research was to determine the impact of nonionic surfactants on drag reduction effect in water and metal oxide nanofluid.Two nonionic surfactants (Rokacet O7 and Rokanol K7) and copper(Ⅱ) oxide water-based nanofluid were examined.Friction factors in a 4 mm diameter pipe for the Reynolds number between 8000 and 50000 were determined.Results showed that addition of nonionic surfactants caused the decrease of friction factor in water and nanofluid.The drag reduction effect was similar in both cases.Presence of nanoparticles in the system has no great influence on drag reduction effect.

  9. Binary Collision Density in a Non-Ideal Gas as a Function of Particle Density, Collision Diameter, and Temperature

    Science.gov (United States)

    Mohazzabi, Pirooz

    2017-09-01

    Using molecular dynamics simulations, binary collision density in a dense non-ideal gas with Lennard-Jones interactions is investigated. It is shown that the functional form of the dependence of collision density on particle density and collision diameter remains the same as that for an ideal gas. The temperature dependence of the collision density, however, has a very different form at low temperatures, where it decreases as temperature increases. But at higher temperatures the functional form becomes the same as that for an ideal gas.

  10. Anisotropic surface strain in single crystalline cobalt nanowires and its impact on the diameter-dependent Young's modulus

    KAUST Repository

    Huang, Xiaohu

    2013-01-01

    Understanding and measuring the size-dependent surface strain of nanowires are essential to their applications in various emerging devices. Here, we report on the diameter-dependent surface strain and Young\\'s modulus of single-crystalline Co nanowires investigated by in situ X-ray diffraction measurements. Diameter-dependent initial longitudinal elongation of the nanowires is observed and ascribed to the anisotropic surface stress due to the Poisson effect, which serves as the basis for mechanical measurements. As the nanowire diameter decreases, a transition from the "smaller is softer" regime to the "smaller is tougher" regime is observed in the Young\\'s modulus of the nanowires, which is attributed to the competition between the elongation softening and the surface stiffening effects. Our work demonstrates a new nondestructive method capable of measuring the initial surface strain and estimating the Young\\'s modulus of single crystalline nanowires, and provides new insights on the size effect. © 2013 The Royal Society of Chemistry.

  11. Dryout-type critical heat flux in vertical upward annular flow: effects of entrainment rate, initial entrained fraction and diameter

    Science.gov (United States)

    Wu, Zan; Wadekar, Vishwas; Wang, Chenglong; Sunden, Bengt

    2017-07-01

    This study aims to reveal the effects of liquid entrainment, initial entrained fraction and tube diameter on liquid film dryout in vertical upward annular flow for flow boiling. Entrainment and deposition rates of droplets were included in mass conservation equations to estimate the local liquid film mass flux in annular flow, and the critical vapor quality at dryout conditions. Different entrainment rate correlations were evaluated using flow boiling data of water and organic liquids including n-pentane, iso-octane and R134a. Effect of the initial entrained fraction (IEF) at the churn-to-annular flow transition was also investigated. A transitional Boiling number was proposed to separate the IEF-sensitive region at high Boiling numbers and the IEF-insensitive region at low Boiling numbers. Besides, the diameter effect on dryout vapor quality was studied. The dryout vapor quality increases with decreasing tube diameter. It needs to be pointed out that the dryout characteristics of submillimeter channels might be different because of different mechanisms of dryout, i.e., drying of liquid film underneath long vapor slugs and flow boiling instabilities.

  12. Measuring stone volume - three-dimensional software reconstruction or an ellipsoid algebra formula?

    Science.gov (United States)

    Finch, William; Johnston, Richard; Shaida, Nadeem; Winterbottom, Andrew; Wiseman, Oliver

    2014-04-01

    To determine the optimal method for assessing stone volume, and thus stone burden, by comparing the accuracy of scalene, oblate, and prolate ellipsoid volume equations with three-dimensional (3D)-reconstructed stone volume. Kidney stone volume may be helpful in predicting treatment outcome for renal stones. While the precise measurement of stone volume by 3D reconstruction can be accomplished using modern computer tomography (CT) scanning software, this technique is not available in all hospitals or with routine acute colic scanning protocols. Therefore, maximum diameters as measured by either X-ray or CT are used in the calculation of stone volume based on a scalene ellipsoid formula, as recommended by the European Association of Urology. In all, 100 stones with both X-ray and CT (1-2-mm slices) were reviewed. Complete and partial staghorn stones were excluded. Stone volume was calculated using software designed to measure tissue density of a certain range within a specified region of interest. Correlation coefficients among all measured outcomes were compared. Stone volumes were analysed to determine the average 'shape' of the stones. The maximum stone diameter on X-ray was 3-25 mm and on CT was 3-36 mm, with a reasonable correlation (r = 0.77). Smaller stones (15 mm towards scalene ellipsoids. There was no difference in stone shape by location within the kidney. As the average shape of renal stones changes with diameter, no single equation for estimating stone volume can be recommended. As the maximum diameter increases, calculated stone volume becomes less accurate, suggesting that larger stones have more asymmetric shapes. We recommend that research looking at stone clearance rates should use 3D-reconstructed stone volumes when available, followed by prolate, oblate, or scalene ellipsoid formulas depending on the maximum stone diameter. © 2013 The Authors. BJU International © 2013 BJU International.

  13. Effect of volume loading on the Frank-Starling relation during reductions in central blood volume in heat-stressed humans

    DEFF Research Database (Denmark)

    Bundgaard-Nielsen, Morten; Wilson, T E; Seifert, Thomas

    2010-01-01

    During reductions in central blood volume while heat stressed, a greater decrease in stroke volume (SV) for a similar decrease in ventricular filling pressure, compared to normothermia, suggests that the heart is operating on a steeper portion of a Frank-Starling curve. If so, volume loading of h...

  14. The Probability Density Functions to Diameter Distributions for Scots Pine Oriental Beech and Mixed Stands

    Directory of Open Access Journals (Sweden)

    Aydın Kahriman

    2011-11-01

    Full Text Available Determine the diameter distribution of a stand and its relations with stand ages, site index, density and mixture percentage is very important both biologically and economically. The Weibull with two parameters, Weibull with three parameters, Gamma with two parameters, Gamma with three parameters, Beta, Lognormal with two parameters, Lognormal with three parameters, Normal, Johnson SB probability density functions were used to determination of diameter distributions. This study aimed to compared based on performance of describing different diameter distribution and to describe the best successful function of diameter distributions. The data were obtaited from 162 temporary sample plots measured Scots pine and Oriental beech mixed stands in Black Sea Region. The results show that four parameter Johnson SB function for both scots pine and oriental beech is the best successful function to describe diameter distributions based on error index values calculated by difference between observed and predicted diameter distributions.

  15. Relationship between diameter of split Hopkinson pressure bar and minimum loading rate under rock failure

    Institute of Scientific and Technical Information of China (English)

    LI Xi-bing; HONG Liang; YIN Tu-bing; ZHOU Zi-long; YE Zhou-yuan

    2008-01-01

    In order to investigate the relationship between bar diameter and loading rate of the split Hopkinson pressure bar(SHPB) setup under the failure of rock specimen and realize the medium strain rate loading of specimen, new SHPB setups with different elastic bar's diameters of 22, 36, 50 and 75 mm were constructed. The tests were carried out on these setups at different loading rates, and the specimens had the same diameter of elastic bars and same ratio of length to diameter. The test results show that the larger the elastic bar's diameter is, the less the loading rate is needed to cause specimen failure, they show good power relationship, and that under the same strain rate loading, specimens are broken more seriously with larger diameter SHPB setup than with smaller one.

  16. Automatic calculation of tree diameter from stereoscopic image pairs using digital image processing.

    Science.gov (United States)

    Yi, Faliu; Moon, Inkyu

    2012-06-20

    Automatic operations play an important role in societies by saving time and improving efficiency. In this paper, we apply the digital image processing method to the field of lumbering to automatically calculate tree diameters in order to reduce culler work and enable a third party to verify tree diameters. To calculate the cross-sectional diameter of a tree, the image was first segmented by the marker-controlled watershed transform algorithm based on the hue saturation intensity (HSI) color model. Then, the tree diameter was obtained by measuring the area of every isolated region in the segmented image. Finally, the true diameter was calculated by multiplying the diameter computed in the image and the scale, which was derived from the baseline and disparity of correspondence points from stereoscopic image pairs captured by rectified configuration cameras.

  17. A continuously variable beam-diameter, high-fluence, Q-switched Nd:YAG laser for tattoo removal: comparison of the maximum beam diameter to a standard 4-mm-diameter treatment beam.

    Science.gov (United States)

    Bernstein, Eric F; Civiok, Jennifer M

    2013-12-01

    Laser beam diameter affects the depth of laser penetration. Q-switched lasers tend to have smaller maximum spot sizes than other dermatologic lasers, making beam diameter a potentially more significant factor in treatment outcomes. To compare the clinical effect of using the maximum-size treatment beam available for each delivered fluence during laser tattoo removal to a standard 4-mm-diameter treatment beam. Thirteen tattoos were treated in 12 subjects using a Q-switched Nd:YAG laser equipped with a treatment beam diameter that was adjustable in 1 mm increments and a setting that would enable the maximally achievable diameter ("MAX-ON" setting) with any fluence. Tattoos were randomly bisected and treated on one side with the MAX-ON setting and on the contralateral side with a standard 4-mm-diameter spot ("MAX-OFF" setting). Photographs were taken 8 weeks following each treatment and each half-tattoo was evaluated for clearance on a 10-point scale by physicians blinded to the treatment conditions. Tattoo clearance was greater on the side treated with the MAX-ON setting in a statistically significant manner following the 1st through 4th treatments, with the MAX-OFF treatment site approaching the clearance of the MAX-ON treatment site after the 5th and 6th treatments. This high-energy, Q-switched Nd:YAG laser with a continuously variable spot-size safely and effectively removes tattoos, with greater removal when using a larger spot-size. © 2013 Wiley Periodicals, Inc.

  18. Evaluating the agreement between tumour volumetry and the estimated volumes of tumour lesions using an algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Laubender, Ruediger P. [German Cancer Consortium (DKTK), Heidelberg (Germany); University Hospital Munich - Campus Grosshadern, Institute of Medical Informatics, Biometry, and Epidemiology (IBE), Munich (Germany); German Cancer Research Center (DKFZ), Heidelberg (Germany); Lynghjem, Julia; D' Anastasi, Melvin; Graser, Anno [University Hospital Munich - Campus Grosshadern, Institute for Clinical Radiology, Munich (Germany); Heinemann, Volker; Modest, Dominik P. [University Hospital Munich - Campus Grosshadern, Department of Medical Oncology, Munich (Germany); Mansmann, Ulrich R. [University Hospital Munich - Campus Grosshadern, Institute of Medical Informatics, Biometry, and Epidemiology (IBE), Munich (Germany); Sartorius, Ute; Schlichting, Michael [Merck KGaA, Darmstadt (Germany)

    2014-07-15

    To evaluate the agreement between tumour volume derived from semiautomated volumetry (SaV) and tumor volume defined by spherical volume using longest lesion diameter (LD) according to Response Evaluation Criteria In Solid Tumors (RECIST) or ellipsoid volume using LD and longest orthogonal diameter (LOD) according to World Health Organization (WHO) criteria. Twenty patients with metastatic colorectal cancer from the CIOX trial were included. A total of 151 target lesions were defined by baseline computed tomography and followed until disease progression. All assessments were performed by a single reader. A variance component model was used to compare the three volume versions. There was a significant difference between the SaV and RECIST-based tumour volumes. The same model sho