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In this article, three different methods for two-phase flow modeling in microchannels and minichannels are presented. They are effective property models for homogeneous two-phase flows, an asymptotic modeling approach for separated two-phase flow, and bounds on two-phase frictional pressure gradient. In the first method, new definitions for two-phase viscosity are proposed using a one-dimensional transport analogy between thermal conductivity of porous media and viscosity in two-phase flow. These new definitions can be used to compute the two-phase frictional pressure gradient using the homogeneous modeling approach. In the second method, a simple semitheoretical method for calculating two-phase frictional pressure gradient using asymptotic analysis is presented. Two-phase frictional pressure gradient is expressed in terms of the asymptotic single-phase frictional pressure gradients for liquid and gas flowing alone. In the final method, simple rules are developed for obtaining rational bounds for two-phase frictional pressure gradient in minichannels and microchannels. In all cases, the proposed modeling approaches are validated using the published experimental data. [ABSTRACT FROM AUTHOR]

Simple rules are developed for obtaining rational bounds for two-phase frictional pressure gradient in minichannels and microchannels. The lower bound is based on the Ali et al. correlation for laminar-laminar flow. This correlation is based on the modification of simplified stratified flow model derived from the theoretical approach of Taitel and Dukler for the case of two-phase flow in a narrow channel. The upper bound is based on Chisholm correlation for laminar-laminar flow. The model is verified using published experimental data of two-phase frictional pressure gradient in circular and non-circular shapes. The published data include different working fluids such as air-water and nitrogen-water mixtures, as well as different channel diameters. The bounds models are also presented in a dimensionless form as two-phase frictional multiplier versus Lockhart-Martinelli parameter for different working fluids such as air-water mixture and nitrogen-water mixture. It is shown that the published data can be well bounded. [ABSTRACT FROM AUTHOR]

This study effectively succeeded in synthesizing CdSe QDs and CdSe- SiO 2 nanocomposites with controllable tunable size and spectacular morphology by using a solvothermal technique. UV–visible spectroscopy was used to study the effect of the growth time of CdSe QDs on the optical properties of its nanocomposite with SiO 2. The structure of the prepared nanocomposites of CdSe- SiO 2 was studied through the measurements of X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy FTIR. The Effective Mass Approximation model (EMA), Simple Exponential Function (SEF), and Polynomial Fitting Functions (PFF) were employed to compute nanoparticle sizes, providing particle sizes of 3.86, 4.19, and 3.72 nm, respectively, for CdSe- SiO 2 nanocomposites (2 min). For the same nanocomposite, these theoretical values were comparable to the experimental values of the particle sizes deduced from measurements of TEM (4.5 nm) and XRD (3.4 nm). The deduced optical parameters of CdSe-SiO 2 nanocomposite, such as refractive index, dielectric constant, optical conductivity, electrical susceptibility, and some others, relied on the growth time of CdSe QDs. The absorption peaks of CdSe -SiO 2 nanocomposites suffered from a bathochromic shift which increases as the growth time of CdSe QDs increases. Increasing the growth time of CdSe QDs resulted in increasing the reflection loss factor and decreasing the optical electronegativity. The values of the volume energy loss function (VELF) are greater than the values of the surface energy loss function (SELF) for the different nanocomposites. Consequently, the fast electrons miss their energies through their propagation within the studied materials more than through traveling on their surfaces. The enhancement of n values of nanocomposites of CdSe-SiO 2 by increasing the growth time can candidate them to be usefully applied as antireflection coating for solar cells. • Modify the structure and enhance the optical properties of CdSe-SiO 2 nanocomposites depending on the growth time of CdSe QD. • Coincidence between theoretical values of particle size and the experimental values deduced from XRD and TEM analysis. • Understanding the structure of the produced nanocomposites by FTIR analysis. [ABSTRACT FROM AUTHOR]

COVID-19 disproportionately impacted patients with cancer as a result of direct infection, and delays in diagnosis and therapy. Oncological clinical trials are resource-intensive endeavors that could be particularly susceptible to disruption by the pandemic, but few studies have evaluated the impact of the pandemic on clinical trial conduct. This prospective, multicenter study assesses the impact of the pandemic on therapeutic clinical trials at two large academic centers in the Northeastern United States between December 2019 and June 2021. The primary objective was to assess the enrollment on, accrual to, and activation of oncology therapeutic clinical trials during the pandemic using an institution-wide cohort of (i) new patient accruals to oncological trials, (ii) a manually curated cohort of patients with cancer, and (ii) a dataset of new trial activations. The institution-wide cohort included 4756 new patients enrolled to clinical trials from December 2019 to June 2021. A major decrease in the numbers of new patient accruals (−46%) was seen early in the pandemic, followed by a progressive recovery and return to higher-than-normal levels (+2.6%). A similar pattern (from −23.6% to +30.4%) was observed among 467 newly activated trials from June 2019 to June 2021. A more pronounced decline in new accruals was seen among academically sponsored trials (versus industry sponsored trials) (P < 0.05). In the manually curated cohort, which included 2361 patients with cancer, non-white patients tended to be more likely taken off trial in the early pandemic period (adjusted odds ratio: 2.60; 95% confidence interval 1.00-6.63), and substantial pandemic-related deviations were recorded. Substantial disruptions in clinical trial activities were observed early during the pandemic, with a gradual recovery during ensuing time periods, both from an enrollment and an activation standpoint. The observed decline was more prominent among academically sponsored trials, and racial disparities were seen among people taken off trial. • During the first peak of the pandemic in the Northeastern US, substantial disruptions to clinical trial conduct occurred. • A progressive recovery was seen during subsequent pandemic periods, both from an enrollment and an activation standpoint. • The decrease seen in new accruals was more pronounced in academically sponsored, as opposed to industry sponsored, trials. • Non-white patients were more likely than white patients to be taken off trial during the pandemic period. [ABSTRACT FROM AUTHOR]

Programmed cell death ligand 1 (PD-L1) tumor proportion score (TPS) is the primary clinically-available biomarker of response to immunotherapy in non-small-cell lung cancer (NSCLC), but factors associated with PD-L1 expression are not well understood. Consecutive nonsquamous NSCLCs with successful PD-L1 assessment and targeted next-generation sequencing were included in this retrospective study. Clinicopathological characteristics, gene mutations, and copy number changes in gene and chromosomal arms were compared among three PD-L1 expression groups: negative (TPS < 1%), low (TPS 1%–49%), and high (TPS ≥ 50%). A Q -value <0.25 was considered significant after multiple comparisons correction. A total of 909 nonsquamous NSCLCs were included. High PD-L1 expression compared with low and negative PD-L1 expression was associated with increased tobacco exposure (median pack-years: 25 versus 20 versus 20, respectively; P = 0.01), advanced stage at diagnosis (76% versus 67% versus 61% with advanced stage of disease, respectively; P < 0.001), and higher tumor mutational burden (TMB) (median 12.2 versus 10.6 versus 10.6 mutations/megabase, respectively; P < 0.001). Negative PD-L1 expression when compared with high PD-L1 expression was associated with: mutations in STK11 (19% versus 5%; Q < 0.001), EGFR (22% versus 11%; Q < 0.001), CTNNB1 (4.3% versus 0.4%; Q = 0.04), APC (5% versus 1%; Q = 0.17), and SMARCA4 (9% versus 4%; Q = 0.20); copy number loss of CD274 (PD-L1, 28% versus 6%; Q < 0.001), PDCD1LG2 (PD-L2, 28% versus 6%; Q < 0.001), and JAK2 genes (27% versus 7%; Q < 0.001), loss of chromosomal arm 9p (23% versus 10%; Q = 0.04), and gain of 1q (46% versus 21%; Q < 0.001). High PD-L1 expression compared with negative PD-L1 expression was associated with copy number gain of CD274 (11% versus 3%; Q = 0.01) and PDCD1LG2 (11% versus 3%; Q = 0.01). NSCLCs with CD274 loss, compared with those without loss, had a lower response rate (23% versus 9%; P = 0.006) and shorter progression-free survival (3.3 versus 2.0 months; P = 0.002) on immunotherapy. PD-L1 expression is associated with specific genomic alterations and clinicopathologic characteristics in nonsquamous NSCLC. • PD-L1 expression is highly variable in nonsquamous NSCLC and is associated with distinct clinicopathological and genomic features. • Tobacco exposure, stage at diagnosis, and tumor mutational burden are associated with PD-L1 expression. • PD-L1 expression ≥50% is associated with copy gain of CD274 (PD-L1) , PDCD1LG2 (PD-L2), JAK2 , and the 9p24.1 locus. • PD-L1 negativity is associated with STK11 , EGFR , CTNNB1 , APC , and SMARCA4 mutations, as well as loss of CD274 , PDCD1LG2 , JAK2 , and the 9p24.1 locus. • CD274 copy loss is associated with lower response rate and shorter progression-free survival to immune checkpoint inhibitors in NSCLC. [ABSTRACT FROM AUTHOR]

• ZnO-reduced Graphene Oxide (ZnO-rGO) nanocomposite was synthesized via co-precipitation method. • XRD, FTIR, and TEM analysis revealed the impact of rGO on the ZnO morphology. • The optical properties of ZnO and ZnO-rGO have been studied. The co-precipitation method was used to synthesize ZnO nanoparticles (NPs). Then, graphene oxide (GO) sheets which were reduced during the reaction process to become (rGO), were embellished with ZnO NPs. The impact of rGO on the structure and morphology of ZnO was investigated using XRD, FTIR, TEM, and SEM techniques. Investigating the optical characteristics was done using UV–vis spectroscopy. ZnO exhibits a hexagonal phase, as proved by XRD. The average crystallite size reduced from 22 to 18 nm after being anchored on rGO sheets. TEM and SEM testify to the presence of ZnO in nanoscales with quasi-spherical shapes, which dispersed homogeneously along the GO sheets. The optical bandgap was increased from 2.57 eV to 3.17 eV for ZnO and ZnO-rGO, respectively. Based on the obtained optical bandgap, the refractive index of ZnO and ZnO-rGO nanocomposite was theoretically determined using different models such as Moss and Ravindra models. ZnO-rGO nanocomposite's ability to change optical characteristics makes it a superior nominee for optoelectronic applications. [ABSTRACT FROM AUTHOR]

Significant toxicity is common in the treatment of advanced non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) and can be associated with adverse events, such as chemotherapy delay or dose reduction, and worse clinical outcomes. Baseline low skeletal muscle (SM) area is a marker of sarcopenia and has been associated with worse survival in other malignancies, but the association of SM area and toxicity in lung cancer is less studied. Patients with locally advanced or oligo-metastatic NSCLC and extensive-stage SCLC treated with concurrent chemoradiation (CRT) from 2002-2013 at a single institution were reviewed. A deep-learning pipeline utilized existing pre-treatment computed tomography scans to calculate SM area at the 3rd lumbar vertebral level. Gold standard SM index (SMI) was calculated, adjusting for height, sex, and dichotomized per previously validated cutoff values. Grade 3 or higher (G3+) toxicity, per NCI CTCAE v5.0, was assessed within 21-days of first chemotherapy cycle. Multivariate analysis (MVA) of toxicity endpoints with SMI and baseline characteristics were analyzed by logistic regression analysis, and with overall survival (OS) using Cox regression analysis. A total of 455 patients met inclusion criteria, with median follow-up of 23.0mo (range 1.0-193.0mo) and median age of 63y (range 29-88y). Among 387 patients with NSCLC, most were clinical stage (AJCC 7th edition) IIIA (43%), IIIB (29%), or IV (11%), while 11% had upfront surgery and adjuvant CRT. Most common chemotherapy regimen was cisplatin-based (48%). Patients with low SMI were more likely to be older (median age 70y vs 62y), ECOG performance status (PS) >0 (75% vs 60%), lower BMI (median BMI 23.3 vs 27.7), and not receive cisplatin-based regimen (39% vs 56%). There was no difference in histology, stage, surgery, or every 3-week (q3w) chemotherapy dosing. On MVA, low SMI was associated with increased risk of G3+ toxicity (OR 1.72, p<0.01) and chemotherapy delay or dose reduction (OR 1.99, p = 0.029). G3+ toxicity was also associated with surgery, but not age, PS, q3w dosing, or regimen. Chemotherapy delay or dose reduction was not associated with age, PS, surgery, and q3w dosing, or regimen. In patients with NSCLC, median OS was 26.2m. G3+ toxicity (HR 1.56, p=0.016), stage 4 (HR 1.280, p=0.003), and cisplatin (HR 1.65, p=0.013) were associated with worse OS on Cox regression, but not low SMI (HR 1.25, p = 0.11), PS, surgery, or regimen. In patients with SCLC, SMI or toxicity were not associated with OS. Low SMI predicted higher risk of G3+ toxicity during first cycle of chemotherapy in lung cancer. High-risk patients with low SMI experienced significant adverse events and should be considered for more aggressive symptom management or alternative treatment strategies. [ABSTRACT FROM AUTHOR]

Abstract: Theoretical and experimental investigation on the transient coupled heat and mass transfer in a radial flow desiccant packed bed has been reported in the present work. An experimental test rig has been designed and constructed to carry out the required experimental measurements. System parameters and flowing air conditions (bed weight, air velocity, air conditions – dry and wet bulb temperatures- at exit of test rig components) are measured and analyzed. A hollow cylindrical packed bed has been used as a desiccant dehumidifier. This configuration decreases the required power to blow air through the bed. In the theoretical study, prediction of air exit conditions from the bed is carried out based on the model of Barlow for the analysis of adsorption and regeneration processes in the desiccant bed. This model uses simple effectiveness equations for steady-state heat and mass exchangers within a finite difference procedure. Air at different conditions of temperature and humidity enters the regenerated bed and the exit temperature and humidity are plotted with time. Acceptable agreement is found between the theoretical and experimental results. The most effective parameters on the system performance are the initial water content of the bed and its initial temperature. Bed cooling during adsorption improves the system performance. [Copyright &y& Elsevier]