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Purpose The purpose of this paper is to investigate the effects of Ha and the Nanoparticles (NP) volume fraction over the irreversibility and heat transport in Darcy–Forchheimer nanofluid saturated lid-driven porous medium. Design/methodology/approach The present paper highlights entropy generation because of mixed convection for a lid-driven porous enclosure filled through a nanoliquid and submitted to a uniform magnetic field. The analysis is achieved using Darcy–Brinkman–Forchheimer technique. The set of partial differential equations governing the considered system was numerically solved using the finite element method. Findings The main observations are as follows. The results indicate that the movement of horizontal wall is an important factor for the entropy generation inside the porous cavity filled through Cu–water nanoliquid. The variation of the thermal entropy generation is linear through NPs volume fraction. The total entropy generation reduces when the Darcy, Hartmann and the nanoparticle volume fraction increase. The porous media and magnetic field effects reduce the total entropy generation. Practical implications Interest in studying thermal interactions by convective flow within a saturating porous medium has many fundamental considerations and has received extensive consideration in the literature because of its usefulness in a large variety of engineering applications, such as the energy storage and solar collectors, crystal growth, food processing, nuclear reactors and cooling of electronic devices, etc. Originality/value By examining the literature, the authors found that little attention has been paid to entropy generation encountered during convection of nanofluids. Hence, this work aims to numerically study entropy generation and heat transport in a lid-driven porous enclosure filled with a nanoliquid.

The objective of this article was to study the reproducibility and reliability of the fetal corpus callosum measurements between two-dimensional (2D) and three-dimensional (3D) acquisitions. This prospective study enrolled 475 fetuses, monitored between 18 and 38 weeks of gestation by two operators. Starting from a transcerebellar axial plane, 3D and 2D mid-sagittal views of the corpus callosum were obtained. Measurements of length and thickness were performed and underwent quality control by independent reviewers. The acquisition time of the two methods was measured. Means, differences, and linear correlations were analyzed using t-test, regression and Pearson's correlation coefficients, and Bland–Altman's plots. This analysis was performed for each operator to test the interobserver reproducibility. Among the 432 cases measured using both methods, 380 (88%) were validated by quality control. The mean corpus callosum length and thickness were essentially the same using 2D and 3D measurements (2D: 33.8 ± 8.7 vs. 3D: 33.7 ± 8.7 mm, 2D: 2.2 ± 0.4 vs. 3D: 2.2 ± 0.4 mm, respectively; mean ± standard deviation [SD]). Linear regression coefficients and Pearson's coefficients were similar for length (2D: 0.8283 and 0.9191 vs. 3D: 0.8271 and 0.9095), but slightly different regarding thickness (2D: 0.6775 and 0.8231 vs. 3D: 0.5831 and 0.7636). Differences between 2D and 3D measurements, considering Bland–Altman's plots and correlated with gestational age, were acceptable (2D: 0.097 ± 0.559 mm, 3D: 0.004 ± 0.111 mm). The acquisition time required was significantly lower for 3D acquisitions (3D: 25.2 ± 14.5 seconds vs. 2D: 35.1 ± 19.4 seconds, p

The aim of our study was to evaluate the efficacy and safety of oral mifepristone use for cervical ripening and the initiation of labor in women with normal pregnancies at or beyond term.We conducted a monocentric, prospective, comparative study on the induction of labor in women with an unfavorable cervix after 37 or more weeks of gestation in the Franck Joly Hospital, French Guiana. The immediate induction of labor by mifepristone was compared to expectant management and the induction of labor with routine cervical ripening agents during two consecutive periods. During the first period, patients received mifepristone (600 mg orally at the moment of enrollment) and were evaluated after 48 h. In the second period, patients did not receive any drugs and were evaluated after 48 h of expectant management.Spontaneous labor or a Bishop Score ≥6 within 48 h of mifepristone administration.enrollment-induction to delivery interval, rate of failed induction, doses of prostaglandin used, mode of delivery, requirement of oxytocin augmentation, and neonatal outcomes.This study enrolled 231 women, 108 in the first and 123 in the second period undergoing induced labor at term caused by various obstetric conditions. There were no significant differences between groups for age, body mass index, gravida, parity, the initial Bishop Score, scarred uterus, or post-term pregnancy. There were statistically significant differences between the two groups concerning spontaneous labor and/ or a Bishop Score ≥6 within 48 h (p10-3) and received doses of misoprostol (p = 0.01). Patients receiving mifepristone were 10 times more likely to be in labor after 48 h of inclusion (RR = 9.98, CI 95 % = [4.47-22.29]). The enrollment-induction to delivery interval was significantly shorter for the mifepristone group (p 0.001). There were no other differences in mode of delivery, placenta abnormalities or neonatal outcomes.Mifepristone efficiently induced cervical ripening and labor initiation in women with normal pregnancies at or beyond term. It may offer an alternative method to the classic induction especially for patients seeking spontaneous labor.

The ability of ultrasound to predict postpartum hemorrhage remains poorly described. The aim of this study was to evaluate whether ultrasound measurement of intrauterine content can predict blood loss and postpartum hemorrhage after vaginal delivery. We used a preliminary prospective monocentric study of 201 women who delivered vaginally after 34 wk of gestation. Measurements were performed 30–45 min after normal vaginal delivery according to strict ultrasonographic criteria. Analysis of the relationship between ultrasound measurements and hemoglobin loss showed a strong linear correlation (R² = 0.59 and R² = 0.4 for isthmic and fundal measurements). The maximal value between the fundal and isthmic measurements seems to provide the best accuracy to predict loss of hemoglobin higher than 3 g/dL (area under the curve [AUC] of the receiver operating characteristic curve, 0.9; 95% confidence interval [CI], [0.76–0.97]) and post-partum hemorrhage (AUC, 0.99; 95%CI, [0.984–0.99]). In case of intrauterine content >2 cm (135/201), the risks of loss of hemoglobin higher than 3 g/dL (5/135 vs. 0/66) and post-partum hemorrhage (11/135 vs. 0/66) were increased, all the more if the intrauterine content was >4 cm (4/16 and 11/16, respectively). Considering the maximal measurement, the most optimal cut-off value for clinical practice could be 2.4 cm (sensibility 100%, specificity 57%) and 4.1 cm (sensibility 100%, specificity 97%) for loss of hemoglobin higher than 3 g/dL and post-partum hemorrhage, respectively.

The paper reports a comprehensive study of heat transfer, mass transfer, and entropy rate of humid air for a single solar still, concerning a typical summer day in a south east region of Tunisia. Transient humid air characteristics such as: partial pressures of components, temperature, humidity ratio, molecular diffusivity, and thermal diffusivity are determined and investigated. Entropy rate equation is derived and studied. Influences of humid air temperature and pressure on heat and mass transfer and on entropy rate are studied. It was found that the increase of water vapor partial pressure and humid air temperature are the best conditions for improving solar still productivity. Humid air can be regarded as a heat engine that generates kinetic energy by transporting energy from heated water surface to inner glass cover surface. Entropy rate of humid air largely depends on dry air entropy rate. The latter presents negative sign, meaning dissipation of convection heat transfer between evaporating and condensing surfaces during circulation. Inversely, entropy rate of water vapor has a positive sign, meaning that it receives energy during phase change by evaporation and transport by humid air from saline water surface towards the inner glass cover surface.

Postpartum hemorrhage is a major cause of maternal death worldwide. Many therapeutic strategies have been developed to reduce maternal morbidity and mortality like oxytocin, prostaglandin, and uterine balloons. A new member of the therapeutic arsenal has recently emerged, the chitosan (Celox®), used since several years by military doctors to stop bleeding of combat wounds. In 2012, a first study was reported with the successful use of chitosan-coated gauze to treat severe postpartum hemorrhage. We report here three cases of the use of chitosan to treat life-threatening obstetric bleeding. In the first case, a pelvic packing with chitosan gauze after hemostatic hysterectomy with persistent bleeding. In the second case, the use of chitosan powder in a case of severe bleeding from multiple vaginal tears. In the third case, the use of chitosan gauze in uterine packing for postpartum hemorrhage by atonia. Postpartum hemorrhage of uterine origin resistant to treatment with prostaglandins can be treated with chitosancoated gauze. This treatment requires no training and its costs are one fifth those of a Bakri® intrauterine balloon. Using these two forms of chitosan, powder and gauze, we have developed a new therapeutic method at our disposal for dealing with the most serious cases of bleeding.

Postpartum hemorrhage is a major cause of maternal death worldwide. Many therapeutic strategies have been developed to reduce maternal morbidity and mortality like oxytocin, prostaglandin, and uterine balloons. A new member of the therapeutic arsenal has recently emerged, the chitosan (Celox®), used since several years by military doctors to stop bleeding of combat wounds. In 2012, a first study was reported with the successful use of chitosan-coated gauze to treat severe postpartum hemorrhage. We report here four cases of the use of chitosan to treat life-threatening obstetric bleeding. In the first case, a pelvic packing with chitosan gauze after hemostatic hysterectomy with persistent bleeding. In the second case, the use of chitosan powder in a case of severe bleeding from multiple vaginal tears. In the third case, the use of chitosan gauze in uterine packing for postpartum hemorrhage by atonia. In the fourth case, the use of chitosan powder for stop bleeding during a hemorrhagic cesarean section. Postpartum hemorrhage of uterine origin resistant to treatment with prostaglandins can be treated with chitosan-coated gauze. This treatment requires no training and its costs are one fifth those of a Bakri® intrauterine balloon. Using these two forms of chitosan, powder and gauze, we have a new therapeutic method at our disposal for dealing with the most serious cases of bleeding.

The performance of a single solar still is numerically studied by solving the energy balance equations, concerning Gabes region. Effects of the glass cover thickness and the saline water depth on water-to-inner glass cover temperature difference and on daily yield for June 21st are determined and graphically presented. It was found that optimum values of glass cover thickness and water depth giving highest productivity are 3 mm, and 1.5 cm, respectively.

The article reports a numerical study of entropy generation in double-diffusive convection through a square porous cavity saturated with a binary perfect gas mixture and submitted to horizontal thermal and concentration gradients. The analysis is performed using Darcy–Brinkman formulation with the Boussinesq approximation. The set of coupled equations of mass, momentum, energy and species conservation are solved using the control volume finite-element method. Effects of the Darcy number, the porosity and the thermal porous Rayleigh number on entropy generation are studied. It was found that entropy generation considerably depends on the Darcy number. Porosity induces the increase of entropy generation, especially at higher values of thermal porous Rayleigh number.

The paper provides a numerical investigation of the entropy generation analysis due to natural convection in an inclined square porous cavity. The coupled equations of mass, momentum, energy and species conservation are solved using the Control Volume Finite-Element Method. Effect of medium permeability and inclination angle on entropy generation is analysed. It was found that according to the Darcy number and the porous thermal Raleigh number values, the entropy generation could be mainly due to heat transfer or to fluid friction irreversibility and that entropy generation reaches extremum values for specific inclination angles., {"references":["A. K. Sen , Natural convection in a shallow porous cavity-the Brinkman\nmodel, int. J. Heat Mess Tran., 5. pp. 855-868. May1987.","Lauriat, G., Prasad, V., Natural convection in a vertical porous cavity: a\nnumerical study for Brinkman-extended Darcy formulation. J. Heat.\nTrans. 109, pp 688-696 Aug. (1987).","P. Alam, S. R. Ansari, and R. Kumar, Numerical study on natural\nconvection in a porous cavity due to patial heating and cooling at\nvertical walls, Int. J. of Appl. Math. and Mech. Vol. 7(18): pp1-21, feb.\n2011.","M. S. Selamat, I. Hashim, M. K. Hasan, transient Natural Convection in\nPorous Square Cavity Heated and Cooled on Adjacent Walls, Math.\nProb. in Eng.Vol 2012, jan. 2012.","B.C. Nader , B.B. Brahim , L. Taieb, Influence of thermal boundary\nconditions on natural convection in a square enclosure partially heated\nfrom below. Int. Comm. in Heat and Mass Trans., vol. 34, pp. 369-379,\nMar.2007.","Shiina, Y., Hishida, M.: Critical Rayleigh number of natural convection\nin high porosity anisotropic horizontal porous layers, Int. J. of Heat and\nMass Trans., Vol 53, pp 1507-1513 Mar. 2010.","A. C. Baytas, optimisation in an inclined enclosure for minimum entropy\ngeneration in natural convection. j. Non-Equilib. Thermodyn. Vol 22, pp\n145-155, Oct.1997.","A. C.Baytas, Entropy generation for natural convection in an inclined\nporous cavity. Int. J. Heat and mass Trans. Vol 43, pp 2089-2099,\nJun.2000.","Famouri, M., Hooman, K.,Entropy generation for natural convection by\nheated partitions in a cavity. Int. Com. in Heat and Mass Trans. Vol 35,\npp 492-502, Apr. 2008.\n[10] N.Hidouri, H. abbassi, M. Magherbi, A. Ben Brahim, Entropy generation\nin double diffusive convection in presence of the Soret effect, progress\nin computational fluid dynamics, Vol. 7, 5 , pp 237 - 246, Jun.2007.\n[11] Hidouri, N., Ben Brahim, A. Influence of Soret and Dufour effects on\nentropy generation in transient double diffusive convection, Int. J.\nExergy, 7, 4, 454-481, Jun. 2010.\n[12] A. Mukhopadhyay, Analysis of entropy generation due to natural\nconvection in square enclosures with multiple discrete heat sources, Int.\nComm. in Heat and Mass Transfer vol.37, pp867-872, Aug. 2010.\n[13] I. Zahmatkesh, on the importance of thermal boundary conditions in heat\ntransfer and entropy generation for natural convection inside a porous\nenclosure, Int. J. of Ther. Sci., 47, pp 339-346, Mar. 2008.\n[14] K. Hooman, F. Hooman, S. R. Mohebpour, Entropy generation for\nforced convection in a porous channel with isoflux or isothermal walls.\nInt. J. Exergy. Vol.5, pp 78-96, Jan. 2008.\n[15] H. J. Saabas, B.R. Baliga, Co-located equal-order control-volume finiteelement\nmethod for multidimensional incompressible fluid flow. Part I:\nFormulation. Numer. Heat Transfer Pt. B-Fund.vol 26, 381-407, Jan.\n1994.\n[16] R. Younsi, A. Harkati, D. Kalache, Numerical simulation of double\ndiffusive natural convection in a porous cavity: opposing flow. The\nArabian J. for Sci. and Eng. Vol 27, pp181-194, Dec. 2002.\n[17] P. Nithiarasu, K.N Seetharamu, T. Sundararajan, Double-diffusive\nnatural convection in an enclosure filled with fluid- saturated porous\nmedium: a generalized non-Darcy approach. Num. Heat Trans. Vol 30,\npp 413- 426, Mar.1996."]}