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Correction to the paper title is given. Also, a look on Fc is presented. [ABSTRACT FROM AUTHOR]

In this paper, experimental and theoretical study of a portable apparatus for extracting water from atmospheric air is presented. The experimental water-extraction unit is designed, manufactured, and tested at the Faculty of Engineering, Mansoura University, Egypt (latitude 31.0409 N and longitude 31.3785 E). The unit extracts water from atmospheric air by using solar energy as the heating source and Calcium Chloride (CaCl 2 ) solution as desiccant material. The unit consists of double-faced conical-finned absorber (64 cm diameter and 64 cm height), double-faced conical transparent surface (68 cm diameter and 68 cm height). The unit is provided with a telescopic stick (carrier), and base. At night, the conical absorber which is made from cloth layer impregnated with desiccant solution is exposed to atmospheric air to allow Calcium Chloride solution to absorb moisture. During daytime, the absorber is covered with the tightly-closed double-faced conical transparent surface which is exposed to solar radiation. As solar energy increases the absorber temperature, the absorbed vapor evaporates from the solution and condenses on the surface. The condensate is collected in a bottle through a hose. Radiation intensity, temperature, cover temperature, ambient temperature, and productivity are recorded at a number of different operating days year-round. The measured accumulated productivity is found to range from 0.3295 to 0.6310 kg/m 2 /day. [ABSTRACT FROM AUTHOR]

Highlights: [•] Prediction of wall friction factor in horizontal annular flow using the asymptotic method is presented. [•] The asymptotic method is simple, explicit and has only one unknown parameter (the fitting or “blending” parameter (n)). [•] Comparison of the asymptotic model with the solution available in the literature is presented. [ABSTRACT FROM AUTHOR]

Abstract: The maintenance of motility, viability and acrosomal integrity of ram spermatozoa for an extended period of time after cryopreservation is important for achieving high pregnancy rates, when using frozen–thawed semen. The most frequently used cryoprotectant is glycerol, which has to be used at low concentrations (under 4%), due to its potential toxicity. The primary objective of this study was to determine the combined effect of sub-optimal glycerol inclusion and cholesterol-loaded cyclodextrin (CLC) in a Tris-based diluent on ram spermatozoal longevity and acrosomal integrity during in vitro incubation, after cryopreservation. Ram semen was treated with 0 or 2mgCLC/100×106 cells in Tris-based diluents containing either 6 or 3% glycerol and frozen in 0.5ml straws. After thawing, the responses of all sperm parameters recorded were not significantly different between sub-optimal glycerol concentration (3%) and optimal glycerol concentration (6%) for untreated semen groups (0mgCLC/100×106). Similarly, no significant differences were recorded between glycerol concentrations when semen samples were treated with 2mgCLC/100×106 cells prior to cryopreservation. However, sperm treated with CLC prior to cryopreservation in diluents containing a sub-optimal concentration of glycerol (3%), recorded significantly higher (P <0.05) percentages of total motile sperm, progressive motility, viability and acrosomal integrity, than for optimal glycerol concentrations (6%) for up to 4h of in vitro incubation, at 38.5°C after cryopreservation and thawing. Results suggest that in ram spermatozoa, a combination of 2mg cholesterol-loaded cyclodextrins (CLC)/100×106 and a sub-optimal concentration of glycerol (3%) in a Tris-based diluent helps to reduce the acrosomal damage observed during cryopreservation, maintaining sperm viability and motility. [Copyright &y& Elsevier]

Abstract: Computer-assisted sperm analyzers (CASA) have become the standard tool for evaluating sperm motility because they provide objective results for thousands of mammalian spermatozoa. Mammalian spermatozoa experience osmotic stress when the glycerol is added to the cells prior to freezing and removal from the cells after thawing. In order to minimize osmotic damage, cryoprotectants having lower molecular weights and greater membrane permeability than glycerol, were evaluated to determine their effectiveness for cryopreserving bull spermatozoa. The aim of this study was to compare the cryopreservation effects of low molecular weight cryoprotectants (ethylene glycol and methanol) to glycerol, on post-thaw CASA sperm parameters. Bull semen was diluted with tris-egg yolk extender containing 3% glycerol, 3, 2 and 1% ethylene glycol or 3, 2 and 1% methanol. Bull semen was frozen in 0.5 straws. Bull spermatozoa exhibited higher percentages (p <0.01) for total (Mot, 72.4%) and progressively (Prog, 29.5%) motilities when frozen in extender containing 3% glycerol compared to 3, 2 and 1% ethylene glycol or 3, 2 and 1% methanol. In conclusion, no advantages were found in using ethylene glycol or methanol to replace glycerol in bull semen freezing. Glycerol provided the best sperm characteristics for bull spermatozoa after freezing and thawing. The possibility of using ethylene glycol or methanol as permeating cryoprotectants for bull semen deserves further investigation, and these cryoprotectants should also be evaluated in extenders that contain disaccharides or cholesterol. [Copyright &y& Elsevier]

Abstract: The convective heat transfer and pressure drop characteristics of flow in corrugated channels have been experimentally investigated. Experiments were performed on channels of uniform wall temperature and of fixed corrugation ratio over a range of Reynolds number, 3220≤ Re ≤9420. The effects of channel spacing and phase shift variations on heat transfer and pressure drop are discussed. Results of corrugated channels flow showed a significant heat transfer enhancement accompanied by increased pressure drop penalty. The average heat transfer coefficient and pressure drop enhanced by a factor of 2.6 up to 3.2 and 1.9 to 2.6 relative to those for parallel plate channel, respectively, depending upon the spacing and phase shift. The friction factor increased with increasing channel spacing and its phase shift. The effect of spacing variations on heat transfer and friction factor was more pronounced than that of phase shift variation, especially at high Reynolds number. Comparing results of the tested channels by considering the flow area goodness factor (j/f), it was better for corrugated channel with spacing ratio, ɛ ≤3.0 and of phase shift, Ø ≤90°. Comparisons of the present data with those available in literature are presented and discussed. [Copyright &y& Elsevier]

In this note, a historical view on the Bejan numbers ( Be ) is presented. There are two definitions of Bejan number ( Be ) in the fields of thermodynamics, fluid mechanics, heat transfer, and mass transfer. A general form of Bejan number ( Be ) is introduced, and application of Bejan number ( Be ) to flows in porous media is shown. The note concludes with a critical discussion of the view that Bejan number in convection ( Be ) is the combination of the Euler ( Eu ) and Reynolds ( Re ) numbers. [ABSTRACT FROM AUTHOR]

Abstract: Using an analogy between thermal conductivity of porous media and viscosity in two-phase flow, new definitions for two-phase viscosity are proposed. These new definitions satisfy the following two conditions: namely (i) the two-phase viscosity is equal to the liquid viscosity at the mass quality=0% and (ii) the two-phase viscosity is equal to the gas viscosity at the mass quality=100%. These new definitions can be used to compute the two-phase frictional pressure gradient using the homogeneous modeling approach. These new models are assessed using published experimental data of two-phase frictional pressure gradient in circular pipes, minichannels and microchannels in the form of Fanning friction factor (f m) versus Reynolds number (Re m). The published data include different working fluids such as R-12, R-22, argon (R740), R717, R134a, R410A and propane (R290) at different diameters and different saturation temperatures. Models are assessed on the basis minimizing the root mean square error (e RMS). It is shown that these new definitions of two-phase viscosity can be used to analyze the experimental data of two-phase frictional pressure gradient in circular pipes, minichannels and microchannels using simple friction models. [Copyright &y& Elsevier]

Commentary is presented on Ahmad and Khan [1]'s paper, where the authors studied activation energy significance in development of bonding of chemical covalent in Sisko magneto-nanofluids flow past a porous curved moving surface. This commentary shows that there is no agreement in the D B and D T units employing the energy & concentration equations. • These comments are increasing the awareness among the journal readers. • Comments are presented on Ahmad and Khan [1]'s paper. • There is a conflict in D B and D T units. [ABSTRACT FROM AUTHOR]

Commentary is presented on Khan et al. (2017) [1]'s paper, where the authors studied 2D magnetohydrodynamic nanofluid flow past the moving wedge. This commentary shows that the parameters λ and m values can be lower than zero. • These comments are increasing the awareness among the journal readers. • Comments are presented on Khan et al. 1 's paper. • The parameters λ and m values can be lower than zero. [ABSTRACT FROM AUTHOR]

A technique for freezing ram and bull spermatozoa in pellet form, using the cold surface of cattle fat was compared to other freezing procedures. Three freezing methods were compared to cryopreserve ram spermatozoa: 0.25 ml straws, pellets frozen on the cold surface of paraffin wax and pellets frozen on the cold surface of cattle fat. In addition, two cryoprotectants, glycerol or sucrose, in an egg yolk–Tris diluent were compared. Ram spermatozoa frozen as pellets on cattle fat exhibited higher percentages of motile cells after thawing (54%) than spermatozoa frozen in straws (49%) or as pellets on paraffin wax (42%, S.E.M.=1; P<0.05). However, the percentages of acrosome intact cells were similar for spermatozoa frozen as pellets (49%) and spermatozoa frozen in straws (48%; P>0.05), but higher than for spermatozoa frozen as pellets on paraffin wax (39%, S.E.M.=1; P>0.05). Ram spermatozoa exhibited higher percentages of motile cells after thawing when the cryoprotectant was sucrose (51%) compared to glycerol (46%; P<0.05). Similarly, acrosomal integrity was greater with sucrose (49%) than with glycerol (42%; P<0.05). Bull spermatozoa exhibited higher percentages of motile cells after thawing, when cells were frozen in straws (47%) than in the pellet form, regardless of the surface on which the pellets were frozen (31–37%, S.E.M.=3; P<0.05). However, bull spermatozoa exhibited higher percentages of motile cells when frozen as pellets on the surface of cattle fat (66%) or dry ice (61%), than when frozen on paraffin wax (53%, S.E.M.=4; P<0.05). In conclusion, although bull spermatozoa survive cryopreservation more effectively in straws, ram spermatozoa can be cryopreserved as pellets on the cold surface of cattle fat using sucrose as the cryoprotectant. This technique is simple, requires little equipment, is less expensive than using straws and may prove useful for cryopreserving ram and possibly bull spermatozoa in developing countries. [Copyright &y& Elsevier]

Programmed death receptor ligand 1 (PD-L1) tumor proportion score (TPS) and tumor mutational burden (TMB) are key predictive biomarkers for immune checkpoint inhibitor (ICI) efficacy in non-small-cell lung cancer (NSCLC). Data on their variation across multiple samples are limited. Patients with NSCLC and multiple PD-L1 TPS and/or TMB assessments were included. Clinicopathologic and genomic data were analyzed according to PD-L1 and TMB variation. In total, 402 PD-L1 sample pairs and 413 TMB sample pairs were included. Concordance between pairs was moderate for PD-L1 (ρ = 0.53, P < 0.0001) and high for TMB (ρ = 0.80, P < 0.0001). Shorter time between biopsies correlated with higher concordance in PD-L1, but not in TMB. Major increases (ΔTPS ≥ +50%) and decreases (ΔTPS ≤ −50%) in PD-L1 were observed in 9.7% and 8.0% of cases, respectively. PD-L1, but not TMB, decreased with intervening ICI (P = 0.02). Acquired copy number loss of CD274 , PDCD1LG2 , and JAK2 were associated with major decrease in PD-L1 (q < 0.05). Among patients with multiple PD-L1 assessments before ICI, cases where all samples had a PD-L1 ≥1%, compared to cases with at least one sample with PD-L1 <1% and another with PD-L1 ≥1%, achieved improved objective response rate and progression-free survival (PFS). Among patients with at least one PD-L1 <1% and one ≥1% before ICI, cases where the most proximal sample was PD-L1 ≥1% had longer median PFS compared to cases where the most proximal PD-L1 was <1%. Among patients with multiple TMB assessments before ICI, patients with a TMB ≥10 mut/Mb based on the most recent assessment, as compared to those with a TMB <10 mut/Mb, achieved improved PFS and overall survival to ICI; instead, no differences were observed when patients were categorized using the oldest TMB assessment. Despite intrapatient concordance in PD-L1 and TMB, variation in these biomarkers can influence ICI outcomes, warranting consideration for reassessment before ICI initiation when feasible. • Intrapatient paired PD-L1 TPS and TMB assessments have good concordance. • Variations in PD-L1 TPS and TMB with clinical implications may occur. • Intervening ICI therapy is associated with decrease in PD-L1 TPS. • Copy number loss in CD274 , PDCD1LG2 , and JAK2 genes are strongly associated with major decrease in PD-L1 TPS (−50% to −100%). • Variations in PD-L1 TPS and TMB have significant impact on outcomes to a subsequent ICI-based therapy. [ABSTRACT FROM AUTHOR]

Eq. (12) in the paper is false. A correct expression is given. Also, comments on the dimensionless parameter (F s) are presented. The parameter (r) is unknown. In addition, the Prandtl number (Pr) is dimensional. [ABSTRACT FROM AUTHOR]

Corrections to the units of magnetic field strength (B 0) and electrical conductivity (σ) in Nomenclature are given so that the momentum equation is correct and the Hartman number (H a) is dimensionless. The similarity variable (η) depends only on r. From the equations of energy and concentration, temperature (T) and concentration (C and n) depend on r, z. In addition, the temperature θ(η) depends only on r while RHS depends on r, z. Hence, there is a discrepancy between LHS & RHS so that the equation of temperature is not valid. Also, the concentration φ(η) and ξ(η) depend only on r while RHS depends on r, z. Hence, there is a discrepancy between LHS & RHS so that the equations of concentration are not valid. Furthermore, a correct B e form is given. [ABSTRACT FROM AUTHOR]

• These comments are increasing the awareness among the journal readers. • Comments are presented on Hayat et al. [1] 's paper. • The correct form of Bejan number is presented. The correct form of Bejan number is presented. [ABSTRACT FROM AUTHOR]

The x-momentum equation is wrong. A correct equation is given. [ABSTRACT FROM AUTHOR]

To investigate the effect of blue light photoactivated riboflavin modified universal adhesives on dentin collagen biodegradation resistance, dentin apparent elastic modulus, and resin-dentin bond strength with interfacial morphology. Dentin slabs were treated with 0.1% riboflavin-5-phosphate modified (powder added slowly while shaking and then sonicated to enhance the dispersion process) Universal Adhesive Scotch Bond and Zipbond™ along with control (non-modified) and experimental adhesives, photoactivated with blue light for 20s. Hydroxyproline (HYP) release was assessed after 1-week storage. Elastic-modulus testing was evaluated using universal testing machine at 24 h. Resin-dentin interfacial morphology was assessed with scanning electron-microscope, after 6-month storage. 0.1% rhodamine dye was added into each adhesive and analyzed using CLSM. Detection of free amino groups was carried out using ninhydrin and considered directly proportional to optical absorbance. Collagen molecular confirmation was determined using spectropolarimeter to evaluate and assess CD spectra. For molecular docking studies with riboflavin (PDB ID file), the binding pocket was selected with larger SiteScore and DScore using Schrodinger PB software. After curing, Raman shifts in Amide regions were obtained at 8 μm levels. Data were analyzed using Two-way analysis of variance (ANOVA, p ≤ 0.05) and Tukey–Kramer multiple comparison post hoc tests. At baseline, bond strength reduced significantly (p ≤ 0.05) in control specimens. However, at 6 months' storage, UVA Zipbond™ had significantly higher μTBS. Resin was able to diffuse through the porous demineralized dentin creating adequate hybrid layers in both 0.1%RF modified adhesives in CLSM images. In riboflavin groups, hybrid layer and resin tags were more pronounced. The circular dichroism spectrum showed negative peaks for riboflavin adhesive specimens. Best fitted poses adopted by riboflavin compound are docked with MMP-2 and -9 proteases. Amide bands and CH 2 peaks followed the trend of being lowest for control UA Scotch bond adhesive specimens and increasing in Amides, proline, and CH 2 intensities in 0.1%RF modified adhesive specimens. All 0.1%RF application groups showed statistically significant (p < 0.05) less levels of HYP released compared to controls. Dentin E appr of riboflavin application was significantly (p < 0.05) more as compared to control groups. Blue light photoactivated 0.1% riboflavin modified adhesives improved the biochemical and biomechanical properties of demineralized dentin as well as the long-term resin-dentin interfacial integrity and bond strength of universal adhesive to dentin. [ABSTRACT FROM AUTHOR]

These comments show that the entropy generation units due to fluid friction (S gen , f) and magnetic field (S gen , m) are kg m−1 s−3 K−2. Hence, the total entropy generation (S gen,total) equation is wrong. Proper correct expressions of S gen , f and S gen , m are given. [ABSTRACT FROM AUTHOR]