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Abstract: A 44-year-old woman underwent left single-lung transplantation for end-stage emphysema due to α1-antitrypsin deficiency in January 2010. Cyclosporine, azathioprine, and prednisolone were administered for immunosuppression and antithymocyte globulin for induction therapy at the time of transplantation. Routine examination of a lung biopsy, 4 months after transplantation, showed nonspecific, diffuse interstitial inflammation with alveolar septal fibrosis. The patient''s clinical status and imaging studies, consistent with nonspecific interstitial pneumonitis, which was considered as signs of acute rejection, worsened within 2 weeks, despite high-dose steroids, change of calcineurin inhibitor, and plasmapheresis. Within a few days after a single, 10-mg, intravenous dose of alemtuzumab, the patient''s health improved markedly. She has remained stable for 4 months on a standard, ambulatory, posttransplant antirejection drug regimen. We have since successfully treated with alemtuzumab three additional patients who developed interstitial lung injury after lung transplantation, who are also summarized in this report. [Copyright &y& Elsevier]

In 2016, medical assistance in dying (MAID) became legal in Canada. Organ donation after MAID can provide donors with the opportunity to fulfill their dying wishes, and end-stage lung patients with the opportunity for lung transplantation (LTx). The objective of this study was to report on the logistics of this process and to assess the short- and intermediate-term outcomes of LTx with lungs from MAID donors. This is a retrospective study of LTx using lung donation from MAID and non-MAID donors at our institution from 02/2018 to 07/2021. A total of 745 lung grafts were recovered (MAID, 38 (5.1%); non-MAID, 707 (94.9%)). MAID donors included those with neurodegenerative diseases (n=33) and end stage organ disorders (n=5). In the MAID group, 13 cases (34%) were transplanted directly, whereas 25 (66%) cases were evaluated on Ex Vivo Lung Perfusion (EVLP) and 19 (76%) of those were used for transplantation (non-MAID; EVLP: 369 (52%), transplanted: 239 (65%)). Two patients had MAID procedure and death declaration at home prior to be transferred to the hospital for organ recovery. Overall, 33 patients received lungs (one double-lung was given to two single lung recipients) from MAID donors, and 565 patients received lungs from non-MAID donors. MAID donors were significantly older than non-MAID donors (56 (51-64) vs. 49 (32-61) yr; p =.0009). Recipient characteristics were similar in both groups, except for a higher incidence of positive virtual crossmatch rate in the MAID group (MAID, 40%; non-MAID, 16%; p =.015). Positive actual crossmatch rate was not different. Short and intermediate-term outcomes were similar between the two groups (Table 1). In this first North American report with LTx using donors after MAID, we demonstrate that recipient outcomes are excellent and similar to patients receiving grafts from non-MAID donors. Therefore, where this practice is permitted, donation after MAID should be strongly considered for LTx as an option to increase the organ donor pool. [ABSTRACT FROM AUTHOR]

Abstract: The present research study investigates the effects of surface roughness amplitude and surface oxide layer thickness on the dynamic behavior of micrometric single water droplets during collision with surfaces at high temperature. Stainless steel-grade 304 (SUS 304) surfaces of different amplitudes of surface roughness; Ra=0.04, 2, 4, 6, 8 and 10 μm, have been considered. Each heat transfer surface was heated up to different temperatures; 1108, 1158 and 1198K, to control the oxide layer thickness over the hot surface. An individual water droplet is ejected from a needle of the micro jet dispenser where the droplet's size and its velocity were controlled independently. The behavior of droplet during the collision with hot surface was observed with a high-speed camera. By analyzing the experimental results, the effects of the surface roughness amplitude, oxide layer thickness, droplet Weber number, and surface superheat on the hot solid–liquid contact time, and on the maximum droplet spread diameter were investigated. Empirical correlations have been deduced describing the relationship between the hydrodynamic characteristics of an individual droplet impinging on a heated surface and concealing the affecting parameters in such process. Also, the comparison between the current results and the results due to other investigators shows the effects of oxide layer thickness and surface roughness amplitude on the impact behavior of water droplet onto the heated surfaces. [Copyright &y& Elsevier]

Abstract: This study investigates the influence of oxide layer over the hot surfaces on the behavior of single droplets impacting the high temperature surfaces using high speed camera. In the present work, an experimental apparatus was installed where direct contact between mono-dispersed water droplet and solid hot surface in the presence of different values of oxide layer (4.5, 6.7, 9.4 and 12.6 μm) over the hot surface was experimentally investigated. The droplets size and its velocity were controlled independently. The results presented the effects of surface oxide layer, droplet velocity, droplet size and surface superheating on the hot solid–liquid contact wettability time and on the maximum droplet spread diameter on the hot surface. Empirical correlations are presented describing the hydrodynamic characteristics of an individual droplet impinging on a heated surface and concealing the affecting parameters for surface oxidation phenomena in such process. Also, the comparison between the obtained results at oxidation phenomena and the results due to others at non oxidation phenomena shows the effect of surface oxidation phenomena on the behavior of single droplet impacting the high temperature surface. These experimental observations provide the validation data required for multi-phase modeling of these phenomena by computational fluid dynamics (CFD) (e.g. Volume of Fluid (VOF) modeling) methods. [Copyright &y& Elsevier]

Abstract: The main objective of this research is to study analytically and experimentally the liquid sheet breakup of a flat fan jet nozzle resulting from pressure-swirling. In this study the effects of nozzle shape and spray pressure on the liquid sheet characteristics were investigated for four nozzles with different exit widths (1.0, 1.5, 2.0 and 2.5mm). The length of liquid sheet breakup, liquid sheet velocity and the size of formed droplets were measured by a digital high speed camera. The breakup characteristics of plane liquid sheets in atmosphere are analytically investigated by means of linear and nonlinear hydrodynamic instability analyses. The liquid sheet breakup process was studied for initial sinuous and also varicose modes of disturbance. The results presented the effect of the nozzle width and the spray pressure on the breakup length and also on the size of the formed droplets. Comparing the experimental results with the theoretical ones for all the four types of nozzles, gives a good agreement with difference ranges from 4% to 12%. Also, the comparison between the obtained results and the results due to others shows a good agreement with difference ranged from 5% to 16%. Empirical correlations have been deduced describing the relation between the liquid sheet breakup characteristics and affecting parameters; liquid sheet Reynolds number, Weber number and the nozzle width. [ABSTRACT FROM AUTHOR]

Surface wettability of a heating surface is one of the most important factors affecting boiling performance. While a biphilic surface (with juxtaposed hydrophilic and hydrophobic regions) is known as a promising technique to enhance water pool boiling at the atmospheric pressure, there is no research regarding its potential for sub-atmospheric applications. In the present study, we have investigated the characteristics of pool nucleate boiling on biphilic surfaces at sub-atmospheric pressures. Biphilic surfaces were made by applying Ni-TFEO (tetrafluoroethylene oligomer) electroplating (with a contact angle of about 140°) on a copper surface. The heat transfer performance of various biphilic surfaces (with different hydrophobic spot diameters and pitches) were measured in the pressure range from atmospheric to 6.9 kPa. At a pressure of 14.0 kPa, the wall superheat at the onset of nucleate boiling was reduced by 12 K on a biphilic surface compared with a mirror-finished copper surface. The experiment with three different biphilic patterns revealed that smaller pitch and diameter of the hydrophobic spots were favorable to heat transfer at 14.0 kPa. The enhancement of HTC over Kutateladze’s correlation reached 270%. A sharp transition from continuous to intermittent boiling, resulting in large deterioration of HTC, was observed on a biphilic surface at a much lower pressure than that on a copper surface. Boiling performance was less affected by the pressure level above the transition pressure. [ABSTRACT FROM AUTHOR]

High-pressure hydrogen at a maximum of 100 MPa in a 1-L-volume vessel is discharged through 0.1-mm- and 0.2-mm-diameter orifices that imitate cracks, and the transient temperature and pressure behavior of the hydrogen in the vessel is presented. The hydrogen at the initial pressure of 100 MPa during its discharge through the ϕ 0.2-mm orifice reaches half of the initial pressure after 16 s, while it takes approximately nine times longer for the ϕ 0.1-mm orifice to reach half of the initial pressure. We theoretically calculate the transient temperature and pressure according to the fundamental equations based on the mass and energy conservations using an accurate equation of state for hydrogen. The actual flow rate through an orifice is generally smaller than the theoretically calculated flow rate because of the contraction flow. Therefore, in this study, we adopt the effective diameters of the orifices instead of the actual diameters, and from comparisons with the experimental pressure, we estimate them to be 0.6 and 0.9 of the actual diameters for the ϕ 0.1-mm and ϕ 0.2-mm orifices, respectively. We use a functional form with a time constant for the heat transfer coefficient to represent the transient temperature behavior, and we describe the time dependence of the heat transfer coefficient. The results show that the calculated temperature and pressure are in good agreement with the experimental values obtained. [ABSTRACT FROM AUTHOR]

Background Post-transplantation de novo and recurrent immunoglobulin A (IgA) deposition (IgAD) in the allograft is commonly observed. However, the association between post-transplantation IgAD and reduced allograft function has not been determined. We therefore investigated the association between reduced allograft function and post-transplantation IgAD using serial allograft biopsies. Methods IgAD was retrospectively analyzed in 45 adults who underwent kidney transplantation for chronic glomerulonephritis, including IgA nephropathy, at Kagawa University Hospital. Allograft biopsy samples were obtained from per protocol biopsies obtained 1 and 3 years after transplantation, as well as from episode biopsies. Factors contributing to post-transplantation IgAD were assessed by calculating adjusted odds ratios (AORs) using logistic regression analysis. Results Of the 45 recipients, 18 had post-transplantation allograft IgAD. The estimated glomerular filtration rates (eGFR) 1, 2, and 3 years after transplantation were lower in the recipients with than without IgAD. Urinalysis was normal in 61% of recipients with IgAD. Reduced allograft function (eGFR <40 mL/min/1.73 m 2 ) 1 year after transplantation was significantly associated with post-transplantation IgAD (AOR = 34.4 [95% CI = 2.35–502], P = .01). Conversely, blood concentrations of mycophenolic acid and latent IgAD from donor kidneys were not significantly associated with post-transplantation IgAD. Conclusion Reduced allograft function may be associated with post-transplantation IgAD in the allograft. [ABSTRACT FROM AUTHOR]

Abstract: The permeation of hydrogen through metals is of great concern in hydrogen containment systems. In this study, hydrogen contained in seamless coiled tube vessels made of SUS 316L and Inconel 625 permeated the vessel walls at temperatures from 573 K to 773 K, and the decreasing interior pressure of the vessels was monitored for an extended period to characterize the behavior of the pressure change. It was found that the pressure became lower than the surrounding atmospheric pressure, and the vessels reached a vacuum. Hydrogen permeabilities through SUS 316L and Inconel 625 were determined from the pressure drop measurements. In order to ensure the reliability of the measurements, the permeabilities were also determined with a gas chromatograph that measured the concentration of hydrogen completely permeating the vessel wall. The permeabilities obtained with the two methods were in good agreement with each other. The pressure drop behavior was compared to, and found to be consistent with, theoretical calculations performed using the obtained permeabilities based on Fick’s law of diffusion. [Copyright &y& Elsevier]

Abstract: Background: Mineral and bone disorder (MBD) is a major complication of chronic kidney disease and remains a major problem even after kidney transplantation. Although early steroid withdrawal protocols have beneficial effects on mineral and bone metabolism, they are also associated with significantly increased rates of acute allograft rejection (AR). Recently, patients have been treated with early rapid corticosteroid reduction protocols, but it is still unclear whether these protocols reduce the rate of MBD. The aim of this study was to evaluate the effects of early rapid corticosteroid reduction on MBD after kidney transplantation. Methods: We retrospectively evaluated 34 adult kidney transplant recipients who were treated with an early rapid corticosteroid reduction protocol. Glucocorticoid treatment was reduced to methylprednisolone 4 mg/d at 1 month after transplantation. Results: The AR rate at 3 years after transplantation was 15%. Bone mineral density was slightly decreased in the femur at 4 months after transplantation but returned to the preoperative level by 24 months after transplantation. There was no significant decrease in the bone mineral density of the lumbar spine during the first year after transplantation. Urinary deoxypyridinoline levels and plasma osteocalcin levels returned to the normal range during the follow-up period. Bone mineral density tended to be lower in female patients than male patients and in patients who underwent long-term pretransplant dialysis than those who did not undergo long-term pretransplant dialysis. Conclusion: The present study found that MBD was temporary in kidney transplant recipients who were treated with an early rapid corticosteroid reduction protocol and that these patients did not have an increased AR rate. [Copyright &y& Elsevier]

Abstract: Studies with the view to application of a curved vibrating wire method to measure hydrogen gas viscosity have been done. A fine tungsten wire with a nominal diameter of 50μm is bent into a semi-circular shape and arranged symmetrically in a magnetic field. The frequency domain response for forced oscillation of the wire is used for calculating the viscosity. Argon, nitrogen, helium and hydrogen viscosities have been measured at room temperature up to 0.7MPa. The deviations with respect to existing equations suggest that with more refinements it may be possible to take gas viscosity measurements with a precision of less than 1%. [Copyright &y& Elsevier]

Abstract: The present study investigates experimentally the effects of thermal properties of the hot surface and droplet characteristics on the droplet evaporation. Cylindrical blocks made of Stainless Steel, Aluminum and Brass with different degrees of surface roughness were used. The droplet diameter and velocity were controlled independently. The behavior of droplet during the collision with hot surface was observed with a high-speed camera. The results presented the effect of the thermal properties of the hot surface, droplet Weber number, droplet velocity, droplet size, hot surface conditions; surface superheat and degree of surface roughness on the solid–liquid contact time and the maximum spread of droplet over the surface. Empirical correlations have been deduced describing the relationship between the hydrodynamic characteristics of an individual droplet impinging on a heated surface and concealing the affecting parameters in such process. Also, the comparison between the current results and the results due to others investigators shows good agreement in which the difference between them ranged from 5% to 25%. [ABSTRACT FROM AUTHOR]