143 research outputs found

    Discrete-Element Modeling of Shear-Induced Particle Migration during Concrete Pipe Flow: Effect of Size Distribution and Concentration of Aggregate on Formation of Lubrication Layer

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    The Paper Seeks to Better Understand the Particulate Mechanics Giving Rise to the Lubrication Layer (LL) in Flows with Wide Particle-Size Distributions (PSD) Typical of Concrete Pumping Applications. the Study Uses a Soft-Sphere Discrete Element Method (DEM) to Simulate the Shear-Induced Particle Migration (SIPM) Mechanism of Formation of the LL. to Provide Realistic Understanding of SIPM and Rheological Heterogeneity of Concrete, Three Wide PSDs (Fine, Medium, and Coarse) and Three Different Concentrations (10 %–40 %) of Five Spherical-Particle Subclasses (1–17 Mm Diameter) Were Investigated. the Radial Evolution of Concentration and Particle Distribution Was Simulated over Time and the LL Formation Was Successfully Simulated. the Predicted LL Thicknesses Compared Well with Experimental Values. the Coupled Effect of PSD, Concentration, and Mean Diameter of Particles on Wall Effect, SIPM, and Rheological Heterogeneities Across the Pipe Was Evaluated. Higher Rheological Heterogeneity Across the Pipe Was Obtained for Higher Concentration and Coarser Particle Size Distributions

    Correlation between Prostate Needle Biopsy and Radical Prostatectomy Gleason Gradings of 111 Cases with Prostatic Adenocarcinoma

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    <p class="MsoNormal" style="margin: 0cm 0cm 0pt; tab-stops: 98.25pt;"><span style="font-size: small;"><span style="font-family: Times New Roman;"><span class="MsoPageNumber"><strong><span style="mso-bidi-language: FA;">Purpose:</span></strong></span><span class="MsoPageNumber"><span style="mso-bidi-language: FA;"> There are conflicting reports in the literature about correlation of biopsy and prostatectomy Gleason scores in prostate carcinoma. The goal of this study was to determine the correlation of grading in these two types of pathologic materials.</span></span></span></span></p><p class="MsoNormal" style="margin: 0cm 0cm 0pt; tab-stops: 98.25pt;"><span style="font-size: small;"><span style="font-family: Times New Roman;"><span class="MsoPageNumber"><strong><span style="mso-bidi-language: FA;">Materials and methods:</span></strong></span><span class="MsoPageNumber"><span style="mso-bidi-language: FA;"> The coupled Hematoxylin and Eosin slides of 111 patients with prostate carcinoma were collected. Gleason scores were determined. Patients who had undergone any therapy except surgery were excluded from the study. Correlation between grades was calculated by determination of correlation coefficient. Accuracy of biopsy grading in prediction of final grade was also determined by measuring the sensitivity, specificity, and positive and negative predictive values.</span></span></span></span></p><p class="MsoNormal" style="margin: 0cm 0cm 0pt; tab-stops: 98.25pt;"><span style="font-size: small;"><span style="font-family: Times New Roman;"><span class="MsoPageNumber"><strong><span style="mso-bidi-language: FA;">Results:</span></strong></span><span class="MsoPageNumber"><span style="mso-bidi-language: FA;"> In 50 cases (45%), grade was underestimated in the biopsy. After dividing the cases into Gleason scores of<span style="mso-spacerun: yes;"> </span>2 to 4, 5 to 6, 7,<span style="mso-spacerun: yes;"> </span>and<span style="mso-spacerun: yes;"> </span>8 to 10, the most of undergraded cases (84.2%)<span style="mso-spacerun: yes;"> </span>were in the first group (Gleason score 2 to 4) and this rate reached 5% in the fourth group (Gleason score 8 to 10). The correlation coefficient measured was 0.535 in grade to grade comparing and 0.514 in group to group comparison of the specimens. In low-grade tumors, grading in biopsy, in spite of high sensitivity (90.9%), had low positive predictive value (26.3%).</span></span></span></span></p><span class="MsoPageNumber"><span style="font-family: Times New Roman;"><strong><span style="font-size: 12pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: FA;">Conclusion:</span></strong><span style="font-size: 12pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: FA;"> There is a moderate direct linear relationship between scores in biopsy and prostatectomy specimens. But there is a high probability of underestimation of real Gleason score of the radical prostatectomy specimen in low-grade tumors. Pathologists and urologists must consider the phenomenon of undergrading in reporting prostate specimens and managing patients.</span></span></span&gt

    1-Methyl tryptophan, an indoleamine 2,3-dioxygenase inhibitor, attenuates cardiac and hepatic dysfunction in rats with biliary cirrhosis

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    Kynurenine Pathway (KP) is the dominant metabolic route of tryptophan which is catalyzed by indoleamine-2,3-dioxygenase (IDO). This pathway is upregulated in liver disease where the level of KP metabolites correlates with the severity of disease. Cirrhosis is associated with cardiac dysfunction, which manifests itself during severe physiological challenges such as liver transplantation. Cardiac dysfunction in cirrhosis is linked to systemic inflammation and impaired cardiac beta-adrenergic signaling pathways. The KP pathway is involved in modulation of cardiac signaling and is upregulated by systemic inflammation. Therefore, this study aimed to evaluate the effect of IDO inhibition on development of cardiac dysfunction in an experimental model of cirrhosis. Cirrhosis was induced by bile duct ligation (BDL). Experimental groups were given either 1-methyl tryptophan (1-MT, 1, 3, 9 mg/kg), or saline. 28 days after BDL, cardiac chronotropic response to epinephrine was assessed ex vivo. HPLC was employed to measure hepatic and cardiac levels of tryptophan, kynurenine and kynurenic acid. Cirrhosis in rats was associated with impaired cardiac chronotropic responsiveness to adrenergic stimulation. 1-MT dose-dependently improved cirrhosis-induced chronotropic dysfunction as well as elevated serum levels of CRP and IL-6 in BDL rats. Hepatic and cardiac kynurenine/tryptophan ratio were elevated in cirrhotic rats and were reduced following 1-MT administration. Chronic administration of 1-MT could also reduce hepatic inflammation, fibrosis and ductular proliferation. 1-MT attenuates cardiac dysfunction in rats with biliary cirrhosis. This protective effect is not limited to the cardiac function as liver histopathologic changes were also improved following chronic 1-MT administration

    Impact of immunosuppressive treatment on liver fibrosis in autoimmune hepatitis

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    The impact of treatment on progression of fibrosis in autoimmune hepatitis (AIH) is unknown. We assessed the changes in liver fibrosis before and after treatment among these patients. Nineteen AIH patients who had paired liver biopsies were studied. Of these, seven had been treated with 6 months of cyclosporine A and the rest with 6 months of prednisolone for induction of remission. Thereafter all had been maintained on azathioprine. Biopsy specimens before and after treatment were reviewed by one pathologist and scored by the Ishak method. Mean fibrosis stages before and after treatment were compared. Also, factors predicting significant fibrosis (stage �3) and cirrhosis (stage �5) at presentation were assessed. Mean interval between biopsies was 3.38 years. Mean fibrosis stage decreased from 4.53 to 2.16 following treatment (P < 0.001). Mean decrement in inflammatory grade was 8 scores (range, 4-10) in patients in whom fibrosis improved, and 2 scores (range, 0-4) in patients in whom fibrosis did not decrease after treatment (P < 0.001). ALT-to-platelet ratio was the best predictor of significant fibrosis and also cirrhosis. Fibrosis commonly improves after immunosuppressive treatment in AIH. ALT-to-platelet ratio can predict accurately the presence of significant fibrosis and cirrhosis in AIH. © 2005 Springer Science+Business Media, Inc

    Adverse Childhood Experiences and Changing Levels of Psychosocial Distress Scores Across Pregnancy in Kenyan Women

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    Background: Adverse childhood experiences (ACEs) have been associated with deleterious effects on mental health in pregnancy. Methods: The ACE International Questionnaire (ACE-IQ) was used to measure neglect, abuse, and household dysfunction. Longitudinal mixed effect modelling was used to test the effect of ACEs on pregnancy-related anxiety, depressive symptoms, and perceived stress at two time points (12–19 and 22–29 weeks) during pregnancy. Results: A total of 215 women who were predominantly married (81%) and had attained tertiary education (96%) were enrolled. Total ACEs were significantly associated with depressive symptoms (r = 0.23, p \u3c 0.05) and perceived stress (r = 0.18, p \u3c 0.05). As depressive symptoms decreased, t (167) = −8.44, p \u3c 0.001, perceived stress increased, t (167) = 4.60, p \u3c 0.001, and pregnancy-related anxiety remained unchanged as pregnancy progressed. Contact sexual abuse (p \u3c 0.01) and parental death or divorce (p = 0.01) were significantly associated with depression over time (p \u3c 0.01). Total ACEs in this study were associated with depressive symptoms early but not late in pregnancy. Conclusions: Higher total ACEs were positively associated with depressive symptoms and perceived stress during pregnancy, suggesting that mental disorders may have an impact on pregnancy outcomes and ought to be addressed. Further validation of the Edinburgh Postnatal Depression Scale (EPDS) tool in local settings is required

    O-C Study of 545 Lunar Occultations from 13 Double Stars

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    International audienceIn this article, we have studied the reports of lunar occultations by this project observation's teams (named APTO) in comparison with other observations of the objects. Thirteen binary stars were selected for this study. All the previous observations of these stars were also collected. Finally, an analysis of O-C of all reports were performed

    COOL-LAMPS III: Discovery of a 25".9 Separation Quasar Lensed by a Merging Galaxy Cluster

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    In the third paper from the COOL-LAMPS Collaboration, we report the discovery of COOL J0542-2125, a gravitationally lensed quasar at z=1.84z=1.84, observed as three images due to an intervening massive galaxy cluster at z=0.61z=0.61. The lensed quasar images were identified in a search for lens systems in recent public optical imaging data and have separations on the sky up to 25".9, wider than any previously known lensed quasar. The galaxy cluster acting as a strong lens appears to be in the process of merging, with two sub-clusters separated by 1\sim 1 Mpc in the plane of the sky, and their central galaxies showing a radial velocity difference of 1000\sim 1000 km/s. Both cluster cores show strongly lensed images of an assortment of background sources, as does the region between them. A preliminary strong lens model implies masses of $M(<250\ \rm{kpc}) = 1.79^{+0.16} _{-0.01} \times 10^{14} M_{\odot}and and M(<250\ \rm{kpc}) = 1.48^{+0.04}_{-0.10} \times 10^{14} M_{\odot}$ for the East and West sub-clusters, respectively. This line of sight is also coincident with a ROSAT ALL-sky Survey source, centered between the two confirmed cluster halos reminiscent of other major cluster-scale mergers.Comment: 13 pages, 6 figures. Submitted to Ap

    COOL-LAMPS. VI. Lens Model and New Constraints on the Properties of COOL J1241+2219, a Bright z = 5 Lyman Break Galaxy and its z = 1 Cluster Lens

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    We present a strong lensing analysis of COOL J1241+2219, the brightest known gravitationally lensed galaxy at z ≥ 5, based on new multiband Hubble Space Telescope (HST) imaging data. The lensed galaxy has a redshift of z = 5.043, placing it shortly after the end of the “Epoch of Reionization,” and an AB magnitude z AB = 20.47 mag (Khullar et al.). As such, it serves as a touchstone for future research of that epoch. The high spatial resolution of HST reveals internal structure in the giant arc, from which we identify 15 constraints and construct a robust lens model. We use the lens model to extract the cluster mass and lensing magnification. We find that the mass enclosed within the Einstein radius of the z = 1.001 cluster lens is M(<5.″77)=1.079−0.007+0.023×1013M☉ , significantly lower than other known strong lensing clusters at its redshift. The average magnification of the giant arc is 〈μ arc〉 = 76−20+40 , a factor of 2.4−0.7+1.4 greater than previously estimated from ground-based data; the flux-weighted average magnification is 〈μ arc〉 = 92−31+37 . We update the current measurements of the stellar mass and star formation rate (SFR) of the source for the revised magnification to log(M⋆/M⊙)= 9.7 ± 0.3 and SFR = 10.3−4.4+7.0 M ⊙ yr−1, respectively. The powerful lensing magnification acting upon COOL J1241+2219 resolves the source and enables future studies of the properties of its star formation on a clump-by-clump basis. The lensing analysis presented here will support upcoming multiwavelength characterization with HST and JWST data of the stellar mass assembly and physical properties of this high-redshift lensed galaxy

    COOL-LAMPS. IV. A Sample of Bright Strongly Lensed Galaxies at 3 < z < 4

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    We report the discovery of five bright, strong gravitationally lensed galaxies at 3 < z < 4: COOL J0101+2055 (z = 3.459), COOL J0104−0757 (z = 3.480), COOL J0145+1018 (z = 3.310), COOL J0516−2208 (z = 3.549), and COOL J1356+0339 (z = 3.753). These galaxies have magnitudes of rAB, zAB < 21.81 mag and are lensed by galaxy clusters at 0.26 < z < 1. This sample nearly doubles the number of known bright lensed galaxies with extended arcs at 3 < z < 4. We characterize the lensed galaxies using ground-based grz/giy imaging and optical spectroscopy. We report model-based magnitudes and derive stellar masses, dust content, and star formation rates via stellar population synthesis modeling. Building lens models based on ground-based imaging, we estimate source magnifications ranging from ∼29 to ∼180. Combining these analyses, we derive demagnified stellar masses in the range log10(M/M)9.6910.75{\mathrm{log}}_{10}({M}_{* }/{M}_{\odot })\sim 9.69-10.75 and star formation rates in the youngest age bin in the range log10(SFR/(Myr1))0.391.46{\mathrm{log}}_{10}(\mathrm{SFR}/({M}_{\odot }\,{\mathrm{yr}}^{-1}))\sim 0.39-1.46, placing the sample galaxies on the massive end of the star-forming main sequence in this redshift interval. In addition, three of the five galaxies have strong Lyα emissions, offering unique opportunities to study Lyα emitters at high redshift in future work

    COOL-LAMPS VI: Lens model and New Constraints on the Properties of COOL J1241+2219, a Bright z = 5 Lyman Break Galaxy and its z = 1 Cluster Lens

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    We present a strong lensing analysis of COOL J1241+2219, the brightest known gravitationally lensed galaxy at z5z \geq 5, based on new multi-band Hubble Space Telescope (HST) imaging data. The lensed galaxy has a redshift of z=5.043, placing it shortly after the end of the Epoch of Reionization, and an AB magnitude z_AB=20.47 mag (Khullar et al. 2021). As such, it serves as a touchstone for future research of that epoch. The high spatial resolution of HST reveals internal structure in the giant arc, from which we identify 15 constraints and construct a robust lens model. We use the lens model to extract cluster mass and lensing magnification. We find that the mass enclosed within the Einstein radius of the z=1.001 cluster lens is M(<5.77'')=1.0790.007+0.0231.079^{+0.023}_{-0.007}, significantly lower than other known strong lensing clusters at its redshift. The average magnification of the giant arc is =7620+40=76^{+40}_{-20}, a factor of 2.40.7+1.42.4^{+1.4}_{-0.7} greater than previously estimated from ground-based data; the flux-weighted average magnification is =9231+37=92^{+37}_{-31} We update the current measurements of the stellar mass and star formation rate (SFR) of the source for the revised magnification, log(M/M)=9.7±0.3\log(M_\star/M_{\odot})=9.7\pm0.3 and SFR=10.34.4+7.0{\rm SFR} = 10.3^{+7.0}_{-4.4} M M_{\odot} yr1^{-1}. The powerful lensing magnification acting upon COOL J1241+2219 resolves the source and enables future studies of the properties of its star formation on a clump-by-clump basis. The lensing analysis presented here will support upcoming multiwavelength characterization with HST and JWST data of the stellar mass assembly and physical properties of this high-redshift lensed galaxy.Comment: Submitted to Ap
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