Abstract
High-grade calcium aluminate cement (CAC) has been successfully synthesized from municipal alumina waste and limestone under mild reaction conditions. Mineralogical composition and ...microstructure of the sintered mixes were investigated using X-ray diffraction and FESEM; valuable cementing phases such as CA, CA
2
, and C
12
A
7
were observed in addition to the C
3
A phase that was detected in the mixes with high CaCO
3
content. Mix CA60 containing 60 wt% alumina waste has achieved the best sinterability (less than 1 vol% porosity) and the highest densification (~ 2.65 g/cm
3
bulk density) at 1450 °C. Densification, cold-crushing strength (CCS), and microstructure of the hydrated cement samples (From Mix CA60) were investigated. The cast cement specimens revealed better density and CCS characteristics (63.1 and 74 MPa at 7 and 28 days, respectively) in comparison with the commercial cement. Conventional castables (5 × 5 × 5 cm
3
) were prepared from mixtures composed of 15 wt% cement and 85 wt% aggregates (40% Al
2
O
3
), where CA60 and commercial cement were used to compare the effect of the manufactured CA60 cement with the commercial one. The castables prepared with CA60 cement have shown a higher strength at 110 °C with 4.5 MPa when compared to the commercial CAC at the same temperature (1.8 MPa). Accordingly, this study contributes not only to preserving the environment from the accumulation of industrial wastes but also to valorizing and adding value to these wastes.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
P-glycoprotein (P-gp) imparts multi-drug resistance (MDR) on the cancers cell and malignant tumor clinical therapeutics. We report a class of newly designed and synthesized oxygen-heterocyclic-based ...pyran analogues (4a-l) bearing different aryl/hetaryl-substituted at the 1-postion were synthesized, aiming to impede the P-gp function. These compounds (4a-l) have been tested against cancerous PC-3, SKOV-3, HeLa, and MCF-7/ADR cell lines as well as non-cancerous HFL-1 and WI-38 cell lines to determine their anti-proliferative potency.The findings demonstrated the superior potency of 4a-c with 4-F, 2-Cl, and 3-Cl derivatives and 4h,g with 4-NO
, 4-MeO derivatives against PC-3, SKOV-3, HeLa, and MCF-7/ADR cell lines.Compounds 4a-c were tested for P-gp inhibition and demonstrated significant vigour against MCF-7/ADR cells with IC
= 5.0-10.7 μM. The Rho123 accumulation assay showed that compounds 4a-c adequately inhibited P-gp function, as predicted. Furthermore, 4a or 4b administration resulted in MCF-7/ADR cell accumulation in the S phase, while compound 4c induced apoptosis by causing cell cycle arrest at G2/M. The molecular docking was applied to understand the likely modes of action and guide us in the rational design of more potent analogs. The investigate derivatives showed their good binding potential for p-gp active site with excellent docking scores and interactions. Finally, the majority of investigated derivatives 4a-c derivatives showed high oral bioavailability, but they did not cross the blood-brain barrier. These results suggest that they have favorable pharmacokinetic properties. Therefore, these compounds could serve as leads for designing more potent and stable drugs in the future.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The synthesis of nanoparticles by green approaches is gaining unique importance due to its low cost, biocompatibility, high productivity, and purity, and being environmentally friendly. Herein, ...biomass filtrate of
isolated from mangrove rhizosphere sediment was used for the biosynthesis of zinc oxide nanoparticles (ZnO-NPs). The bacterial isolate was identified based on morphological, physiological, and 16S rRNA. The bio-fabricated ZnO-NPs were characterized using color change, UV-visible spectroscopy, FT-IR, TEM, and XRD analyses. In the current study, spherical and crystalline nature ZnO-NPs were successfully formed at a maximum SPR (surface plasmon resonance) of 380 nm. The bioactivities of fabricated ZnO-NPs including antibacterial, anti-
, and larvicidal efficacy were investigated. Data analysis showed that these bioactivities were concentration-dependent. The green-synthesized ZnO-NPs exhibited high efficacy against pathogenic Gram-positive bacteria (
and
), Gram-negative bacteria (
and
), and unicellular fungi (
) with inhibition zones of (12.33 ± 0.9 and 29.3 ± 0.3 mm), (19.3 ± 0.3 and 11.7 ± 0.3 mm), and (22.3 ± 0.3 mm), respectively, at 200 ppm. The MIC value was detected as 50 ppm for
,
, and
, and 200 ppm for
and
with zones of inhibition ranging between 11.7 ± 0.3-14.6 ± 0.6 mm. Moreover, the biosynthesized ZnO-NPs showed high mortality for
with percentages of 100 ± 0.0% at 200 ppm after 24 h as compared with zinc acetate (44.3 ± 3.3%) at the same concentration and the same time.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Janus kinase (JAK) is a family of cytoplasmic non-receptor tyrosine kinases that includes four members, namely JAK1, JAK2, JAK3, and TYK2. The JAKs transduce cytokine signaling through the JAK-STAT ...pathway, which regulates the transcription of several genes involved in inflammatory, immune, and cancer conditions. Targeting the JAK family kinases with small-molecule inhibitors has proved to be effective in the treatment of different types of diseases. In the current review, eleven of the JAK inhibitors that received approval for clinical use have been discussed. These drugs are abrocitinib, baricitinib, delgocitinib, fedratinib, filgotinib, oclacitinib, pacritinib, peficitinib, ruxolitinib, tofacitinib, and upadacitinib. The aim of the current review was to provide an integrated overview of the chemical and pharmacological data of the globally approved JAK inhibitors. The synthetic routes of the eleven drugs were described. In addition, their inhibitory activities against different kinases and their pharmacological uses have also been explained. Moreover, their crystal structures with different kinases were summarized, with a primary focus on their binding modes and interactions. The proposed metabolic pathways and metabolites of these drugs were also illustrated. To sum up, the data in the current review could help in the design of new JAK inhibitors with potential therapeutic benefits in inflammatory and autoimmune diseases.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
•The performance of solar still coupled with parabolic trough collector (PTC) was experimentally studied.•Freshwater productivity for solar still with PTC is higher than that for conventional solar ...still.•Daily productivity of conventional solar still and solar still with tracked PTC is 10.93 and 4.51 kg/m2 in summer.•The efficiency of solar still in summer is greater than winter and the efficiency of conventional solar still is the largest.•Cost of one liter of yield freshwater for solar still with tracked PTC is the lowest (0.0234 $/L).
The performance of coupling parabolic trough collector (PTC) with double slope solar still is investigated experimentally. The incident solar energy on the PTC is transferred to the solar still by oil pipes connected with finned-piped loop heat exchanger imbedded in the solar still. The experiments are conducted at summer and winter times for three systems; conventional solar still, solar still with fixed PTC and with tracked PTC and for two cases of saline water depth in the basin 20 and 30 mm. The results illustrate that the solar still with PTC has higher sill temperature and productivity compared with conventional solar still. The freshwater productivity of solar still with tracked PTC is higher than that of fixed PTC by about 28.1% and for conventional solar still by about 142.3% at saline water depth 20 mm in summer. Freshwater productivity is about 8.53 kg/m2/ day and 4.03 kg/m2/day for solar still coupled with fixed PTC in the summer and winter respectively. The results also illustrate that the performance of solar still in winter is smaller than summer for all studied cases and systems. In summer and at saline water depth 20 mm, the daily efficiency of the conventional solar still, solar still with fixed PTC and solar still with tracked PTC are 36.87, 23.26 and 29.81% respectively.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
6.
MXenes for Plasmonic Photodetection Velusamy, Dhinesh Babu; El‐Demellawi, Jehad K.; El‐Zohry, Ahmed M. ...
Advanced materials,
08/2019, Volume:
31, Issue:
32
Journal Article
Peer reviewed
Open access
MXenes have recently shown impressive optical and plasmonic properties associated with their ultrathin‐atomic‐layer structure. However, their potential use in photonic and plasmonic devices has been ...only marginally explored. Photodetectors made of five different MXenes are fabricated, among which molybdenum carbide MXene (Mo2CTx) exhibits the best performance. Mo2CTx MXene thin films deposited on paper substrates exhibit broad photoresponse in the range of 400–800 nm with high responsivity (up to 9 A W−1), detectivity (≈5 × 1011 Jones), and reliable photoswitching characteristics at a wavelength of 660 nm. Spatially resolved electron energy‐loss spectroscopy and ultrafast femtosecond transient absorption spectroscopy of the MXene nanosheets reveal that the photoresponse of Mo2CTx is strongly dependent on its surface plasmon‐assisted hot carriers. Additionally, Mo2CTx thin‐film devices are shown to be relatively stable under ambient conditions, continuous illumination and mechanical stresses, illustrating their durable photodetection operation in the visible spectral range. Micro‐Raman spectroscopy conducted on bare Mo2CTx film and on gold electrodes allowing for surface‐enhanced Raman scattering demonstrates surface chemistry and a specific low‐frequency band that is related to the vibrational modes of the single nanosheets. The specific ability to detect and excite individual surface plasmon modes provides a viable platform for various MXene‐based optoelectronic applications.
Plasmonic photodetection in Mo2CTx MXene flexible thin films is demonstrated. The photocurrent generation in Mo2CTx is principally controlled by surface plasmon‐assisted hot electrons. The distribution of various surface plasmon modes over individual Mo2CTx nanosheets is visualized by the combination of scanning transmission electron microscopy and ultrahigh‐resolution electron energy‐loss spectroscopy.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Objective To determine factors affecting the stone-free rate and complications of percutaneous nephrolithotomy (PNL) for treatment of staghorn stones. Methods The computerized database of patients ...who underwent PNL for treatment of staghorn stones between January 2003 and January 2011 was reviewed. All perioperative complications were recorded and classified according to modified Clavien classification system. The stone-free rate was evaluated with low-dose noncontrast computed tomography (CT). Univariate and multivariate statistical analyses were performed to determine factors affecting stone-free and complication rates. Results The study included 241 patients (125 male and 116 female) with a mean age of 48.7 ±14.3 years. All patients underwent 251 PNL (10 patients had bilateral stones). The stone-free rate of PNL monotherapy was 56% (142 procedures). At 3 months, the stone-free rate increased to 73% (183 kidneys) after shock wave lithotripsy. Independent risk factors for residual stones were complete staghorn stone and presence of secondary calyceal stones (relative risks were 2.2 and 3.1, respectively). The complication rate was 27% (68 PNL). Independent risk factors for development of complications were performance of the procedure by urologists other than experienced endourologist and positive preoperative urine culture (relative risks were 2.2 and 2.1, respectively). Conclusion Factors affecting the incidence of residual stones after PNL are complete staghorn stones and the presence of secondary calyceal stones. Complications are significantly high if PNL is not performed by an experienced endourologist or if preoperative urine culture is positive.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Hydrogel products constitute a group of polymeric materials, the hydrophilic structure of which renders them capable of holding large amounts of water in their three-dimensional networks. Extensive ...employment of these products in a number of industrial and environmental areas of application is considered to be of prime importance. As expected, natural hydrogels were gradually replaced by synthetic types due to their higher water absorption capacity, long service life, and wide varieties of raw chemical resources. Literature on this subject was found to be expanding, especially in the scientific areas of research. However, a number of publications and technical reports dealing with hydrogel products from the engineering points of view were examined to overview technological aspects covering this growing multidisciplinary field of research. The primary objective of this article is to review the literature concerning classification of hydrogels on different bases, physical and chemical characteristics of these products, and technical feasibility of their utilization. It also involved technologies adopted for hydrogel production together with process design implications, block diagrams, and optimized conditions of the preparation process. An innovated category of recent generations of hydrogel materials was also presented in some details.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Objective
To compare percutaneous nephrostomy tube versus JJ stent as an initial urinary drainage procedure in kidney stone patients presenting with acute kidney injury.
Methods
Between January 2017 ...and January 2019, 143 patients with acute kidney injury secondary to obstructive kidney stone were prospectively randomized into the percutaneous nephrostomy tube group (71 patients) and JJ stent group (72 patients) at Beni‐Suef University Hospital, Beni‐Suef, Egypt. Exclusion criteria included candidates for acute dialysis, fever (>38°C), pyonephrosis, pregnancy and uncontrolled coagulopathy. The period required for serum creatinine normalization, failure of insertion, operative and fluoroscopy time were recorded. Definitive stone management for proximal ureteral stones >1.5 cm consisted of percutaneous nephrolithotomy for the percutaneous nephrostomy group and ureteroscopic laser lithotripsy for the JJ stent group. For stone size <1.5 cm, ureteroscopy or shockwave lithotripsy was carried out for both groups. Percutaneous nephrolithotomy was carried out for renal stones >2 cm, and shockwave lithotripsy for stones <2 cm. Distal and mid ureteral stones were treated by ureteroscopy.
Results
The percutaneous nephrostomy group had shorter operative time (P = 0.001). There was no significant difference in the recovery period for normalization of serum creatinine between both groups (P = 0.120). Procedural failure, ureteric mucosal injury and perforations increased in the case of male sex, stone size >1.5 cm and upper ureteric stones in the JJ stent group. Procedural failure, pelvic perforations and intraoperative bleeding increased in case of male sex, mild hydronephrosis and stone size >2.5 cm in the percutaneous nephrostomy group. Suprapubic pain, urethral pain and lower urinary tract symptoms were significant in the JJ stent group. The presence of a JJ stent directed us toward ureteroscopy (P = 0.002) and the presence of a percutaneous nephrostomy directed us toward percutaneous nephrolithotomy (P = 0.001).
Conclusions
Percutaneous nephrostomy facilitates subsequent percutaneous nephrolithotomy, especially when carried out by a urologist, and it has a higher insertion success rate, a shorter operative time and a lesser incidence of postoperative urinary tract infection than a JJ stent. A JJ stent facilitates subsequent ureteroscopy, but operative complications can increase in the case of proximal ureteral stones >1.5 cm.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
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