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A detailed analysis of the ignition–extinction and hysteresis behavior of the two widely used catalytic reactor models (packed-bed and monolith) for the case of a single exothermic reaction is presented. First, limiting models are used to determine the minimum adiabatic temperature rise and/or catalyst activity needed to observe hysteresis behavior. Next, explicit expressions are provided for estimating the feed temperature or space time at ignition (light-off) and extinction (blow-out) as a function of the adiabatic temperature rise (or inlet concentration of limiting reactant), effective thermal conductivity, time and length scales (reactor, tube/channel diameter, effective diffusion length and pore size), catalyst activity (or dilution) and heat loss. It is shown that various limiting reactor models such as the thin-bed, long-bed, lumped thermal, adiabatic and strongly cooled cases that are defined in terms of various inter- and intraphase heat and mass dispersion time scales can be used to derive scaling relations that are useful in predicting the ignition/extinction loci for both laboratory scale (with heat exchange) and large scale (near adiabatic) reactors.

Background The near-death experiences (NDE) in dialysis patients of our country have not been previously studied. The objective of this study is to investigate the characteristics of NDEs in patients on dialysis. Materials and Methods We performed a cross sectional study of the adult patients of chronic kidney disease stage 5 without dialysis and on dialysis who survived cardiac arrest by cardiopulmonary resuscitation (CPR) as per ACLS (Advanced Cardiac Life Support) guidelines and who sustained pulseless ventricular tachycardia/ventricular fibrillation and received CPR and/or direct cardioversion. We used two scales, Greyson’s NDE scale and Ring’s Weighted Core Experience Index (WCEI). Results We performed the study between 2016 and 2018. A total of 29 patients were included. The data based on Greyson’s NDE scale and Ring’s Weighted Core Experience Index (WCEI)were collected. Conclusions Our study brings a perspective of NDE in CKD and dialysis patients. A similar study of NDE in dialysis patients should be considered by other nephrologists.

Summary We present thermodynamic modeling and pH measurements of fluid systems containing acid-gases (e.g., CO2 and H2S), water, and hydrocarbons—replicating the production and shutdown conditions in sour fields—for the purpose of evaluating top-of-line corrosion (TLC) and wellbore integrity and screening/selection of the proper wellbore materials. In particular: An equation of state (EOS) model using Peng-Robinson EOS in combination with the Huron-Vidal (HV) mixing rule for an aqueous subsystem is developed. In the model, subject EOS parameters are calibrated against existing thermodynamic data (saturation data for pure components and solubility data for binary systems) in literature. New in-situ pH measurement data are presented for a model system corresponding to a sour field. It was found that the wellbore can be subjected to pH levels as low as 2.7 with reservoir fluid containing 12 mol% CO2 and 88 mol% CH4 with downhole flowing conditions of 200 bar and 150°C and wellhead shut-in conditions of 300 bar and 4°C, as observed from the experiments. A modeling workflow is developed to estimate pH of the condensed water as a function of temperature and composition of the aqueous phase. The comparison between prediction and experimental measurement shows a very good match between the two (within pH ±0.1). Such studies (pH measurements and prediction) are not available in the literature but play important roles in material screening and assuring wellbore integrity for sour fields. More importantly, sensitivity analysis can be performed to investigate the effects of various factors (such as reservoir temperature/pressure, shutdown conditions, and compositions or extent of souring) on pH prediction. Furthermore, the methodologies developed through this work can also be extended to reservoir facilities, pipelines, sour gas disposal/handling units, and downstream systems such as water utilities, reactor plants, and refineries. The work can also support regulation/licensing for these sour systems.

In the present study, we performed a comparative stage specific pathological and molecular marker evaluation of TMPRSS2-ERG fusion and PTEN loss-driven (TMPRSS2-ERG.Pten(flox/flox)) versus non-fusion driven prostate tumorigenesis (Hi-Myc) in mice. Anterior, ventral, and dorsolateral prostates were collected from mice at different ages (or time points post-Cre induction). Results indicated that growth and progression of prostatic intraepithelial lesions to adenocarcinoma stages occurred in both mice models albeit at different rates. In the TMPRSS2-ERG. Pten(flox/flox) mice, the initiation of tumorigenesis was slow, but subsequent progression through different stages became increasingly faster. Adenocarcinoma stage was reached early on; however, no high-grade undifferentiated tumors were observed. Conversely, in the Hi-Myc(+/−) mice, tumorigenesis initiation was rapid; however, progression through different stages was relatively slower and it took a while to reach the more aggressive phenotype stage. Nevertheless, at the advanced stages in the Hi-Myc(+/−) mice, high-grade undifferentiated tumors were observed compared to the later stage tumors observed in the fusion-driven TMPRSS2-ERG. Pten(flox/flox) mice. These results were corroborated by the stage specific-pattern in the molecular expression of proliferation markers (PCNA and c-Myc); androgen receptor (AR); fusion-resultant over expression of ERG; Prostein (SLC45-A3); and angiogenesis marker (CD-31). Importantly, there was a significant increase in immune cell infiltrations, which increased with the stage of tumorigenesis, in the TMPRSS2-ERG fusion positive tumors relative to fusion negative tumors. Together, these findings are both novel and highly significant in establishing a working preclinical model for evaluating efficacy of interventions during different stages of tumorigenesis in TMPRSS2-ERG fusion driven PCa.