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Smart windows with long-persistent phosphorescence, ultraviolet (UV) light protection, high transparency, and high rigidity were developed by easily immobilizing varying ratios of lanthanide-activated aluminate phosphor nanoscale particles within a composite of recycled polyester/cellulose nanocrystals (RPET/CNC). Cellulose nanocrystals were prepared from rice straw waste. Cellulose nanocrystals were used at low concentration as both crosslinker and drier to improve both transparency and hardness. The phosphor nanoscale particles must be distributed into the recycled polyester/cellulose nanocrystals composite bulk without agglomeration to produce transparent RPET/CNC substrates. Photoluminescence characteristics were also studied using spectroscopic profiles of excitation/emission and decay/lifetime. The hardness efficiency was also examined. This transparent recycled polyester waste/cellulose nanocrystals nanocomposite smart window has been shown to change colour under UV light to strong green and to greenish-yellow when it is dark, as proved by Commission Internationale de l'éclairage (CIE) laboratory colour parameters. It was found that the afterglow RPET/CNC smart window had phosphorescence intensities of 428, 493, and 523 nm upon excitation at 368 nm. There was evidence of improved UV shielding, photostability, and hydrophobic activity. In the presence of a low phosphor ratio, the luminescent RPET/CNC substrates showed quick and reversible fluorescence photochromic activity when exposed to UV radiation.

A lab-on-paper colorimetric sensor for detection and quantification of bacterial meat spoilage is reported. Bromocresol purple (BCP) and bromothymol blue (BTB) were used for the construction of the proposed sensor. An Android application allowing fast detection and accurate quantification of bacteria in the spoiled chicken meat samples was developed. The sensor was applied to the determination of spoilage in real chicken-meat samples, at chiller and room temperatures, and can be used for producing smart meat-packaging films. Linearity ranges were found to be 11.2 × 103 to 1.12 × 106 and 38.0 × 103 to 1.12 × 106 CFU g−1 for BTB and BCP, respectively. The calibration plots showed correlation coefficients (r) of 0.9998 (slope: 2.48 g CFU−1) and 0.9999 (slope: 1.95 g CFU−1) in case of bromothymol blue and bromocresol purple, respectively. The Android application uses standard images to plot a calibration curve for calculating the microbial count in the samples and relates it to the standard limits. Thereafter, the application shows a message with the product's freshness degree ranging from excellent to poor.

The dispersion of filler in a polymer matrix has a great effect on the structural-property relationship of the formed composite. In this context, surface modification of reduced graphene oxide (RGO) by hyperbranched polyester (PES) has been performed to facilitate its incorporation in polycaprolactone (PCL) matrix by melt blending technique. The structure of the modified reduced graphene oxide (mRGO) was confirmed by Fourier transform infrared (FTIR), and its morphology was studied with transmission electron microscope (TEM). Three main formulations, PCL/RGO and PCL/mRGO containing the same graphene content compared with the neat PCL, were prepared under melt conditions. The morphology and contact angle measurements for the prepared films were demonstrated. The impact of incorporated RGO and mRGO on the thermal and mechanical properties of the PCL matrix was studied. The results emphasized no change in thermal stability of the polymer composites after incorporation of the fillers while the films exhibited an improvement in the strength, the stiffness and ductility. Investigation of water sorption kinetics showed decreasing in the diffusion coefficient for all films reinforced with the nanofillers. Moreover, gas and water permeability displayed improvement in the barrier properties. Antimicrobial activity investigations revealed that films reinforced with mRGO exhibited high bactericidal activity against gram-positive bacteria compared with the neat PCL and those containing RGO. Moreover, incorporation of the prepared nanofillers showed a significant enhancement of the biodegradability of PCL polymer.

Numerous works have been reported in order to enhance the barrier properties of the polystyrene (PS). In this work, hydrophilic graphene oxide (GO), prepared by the Hummer method, was surface-grafted with hydrophobic poly(4-vinylbenzyl chloride), p(VBC), via in situ radical polymerization approach. The graphene oxide/poly(4-vinylbenzyl chloride), GP(VBC), was then dispersed in the polystyrene matrix in order to obtain nano-composite thin films of different filler ratios (5, 10, 15, 20, and 25) wt%. The modified GO and its corresponding films were characterized by X-ray diffraction, Fourier transform infrared, transmission electron microscope, field emission scanning electron microscope, thermal gravimetric analysis, and contact angle. Mechanical properties of the films were studied as well. The results indicated that the surface modification step improved the dispersion of GO within the polystyrene film due to the hydrophobic nature of modified GO. Consequently, an obvious enhancement of thermal stability and mechanical properties of the PS films loaded with GP(VBC) compared with the pure films was noticed. The rate of water vapor permeability showed an abrupt decrease even at the lowest loading percentage of the filler, which is 5 wt%. The antimicrobial activity of the fabricated polystyrene nano-composite films was also investigated against deleterious pathogens. As a net result, the composite films revealed superior properties thanks to the inclusion of the GP(VBC). This present work paves the way for the next generation of high barrier and bactericide polystyrene packaging with an economic impact.

This study provided a facile approach for the development of antifouling and antibacterial polyethersulfone (PES) composite film. Mainly, hyperbranched polyester-amide (PESAM) was used as both the reducing and capping agent for the in situ formation of AgNPs. The nanoparticles were intensively investigated using Fourier transform infrared spectroscopy (FTIR), ultra-violet spectroscopy (UV-vis), scanning and transmission electron microscopy (SEM & TEM) and X-ray diffraction (XRD). AgNPs were narrowly distributed with an average particle size of about 6 nm. PESAM was mixed with PES to realize free-standing film using the phase inversion method. The inclusion of PESAM in the composite film significantly improved hydrophilicity as confirmed by the contact angle measurements. Furthermore, SEM and EDX investigations confirmed that PESAM induced the in situ formation of AgNPs not only on the film surface but also inside its macro-voids. The composite film (PES/PESAM/Ag) displayed significant antibacterial potential against Gram positive and Gram negative bacteria. Overall, the described method paves the way towards development of advanced PES composite films with antimicrobial properties for broad application areas that include desalination membranes or active packaging materials.

Isolation of cellulose nanofibers (CNF) using cellulase immobilized on cheap and easily formed polymeric gel disks is discussed. Such gel disks based on carrageenan gel coated with hyperbranched polyamidoamine that can covalently bind to cellulase through glutaraldehyde spacer. Thermal and mechanical stability of the coated gel disks were significantly improved. Free and immobilized cellulase exhibited maximum activities at 50 °C and pH 5. However, immobilized cellulase exhibited broader temperature stability than in the free form. Additionally, immobilized cellulase gel disks can be easily separated and reused with great reusability capacity of about 85% of the initial activity after six cycles. Immobilized cellulase was capable to disintegrate cellulose fibers providing nanofibers with diameter of 15–35 nm and several micrometers long. Overall, enhanced thermal stability and reusability of immobilized cellulase pave the way for its use in industrial production of CNF that can be applicable for biomedical and food packaging applications.

This work represents the synthesis of nanocomposites based hyperbranched polyester (HPES) and ZnO nanorods (ZnO NRs) as photocatalysts. The nanorods were prepared by thermal treatment of Zn acetate. The nanocomposites were synthesized either by adding of the nano-rods polycondensation reaction (in-situ method, I-HPES/ZnO), or by ex-situ mixing technique (E-HPES/ZnO). The as-prepared ZnO NRs and their nanocomposites were characterized by X-ray diffraction (XRD), surface area (SBET), energy-dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR) and UV–Viz. absorption. Transmission electron microscope (TEM) revealed that the formed NRs are lower than 40 nm in diameter and higher than 100 nm in length. Photocatalytic investigations clarified that modified ZnO-NRs acquire higher reactivity after modification with HPES. The highest photocatalytic degradation were given by E-HPES/ZnO. Durability test proved the feasibility of using the formed nanocomposites several times in the degradation system on the other hand, ZnO suffered a pronounced decrease in the photocatalytic activity. Antibacterial activity emphasized that the obtained nanocomposites have inhibition effect against harmful microorganisms higher than ZnO NRs.

The activity and close regulation of nuclear factor kappaB (NF-κB) transcription factors is critical for a variety of cellular processes including inflammation, immunity, differentiation and cell survival. Thus, dysregulation of the NF-κB system could lead to serious diseases, e.g. uncoordinated growth of the normal tissue during the development of cancer. Transcriptional activity of the NF-κB factor RelA is regulated by a number of mechanisms which comprise ubiquitinylation by a multimeric ubiquitin ligase containing Elongins B and C, cullin-2 (Cul2) and suppressor of cytokine signaling 1 (SOCS1), but also USP48-dependent deubiquitinylation. Further, USP48 promotes cell survival and antagonizes also other E3 ligase functions which are involved in genome stability and DNA repair. The regulation of RelA by USP48 has been investigated in detail, but the domains of USP48 and RelA for direct interaction are not known. In this study we report that USP48 interacts physically with RelA in the nucleus. Further, we show by overexpression of truncated proteins that the catalytic USP domain of USP48 interacts with the N-terminal region of the Rel homology domain (RHD) of RelA. This study provides first evidence that the USP domain of USP48 is important for the physical association with substrate proteins, and a suitable target for small molecule inhibitors for therapeutic intervention strategies.

This study aims to evaluate changes in tarsal bones relationship after the use of one week accelerated Ponseti method in the treatment of severe idiopathic clubfoot using MRI. We hypothesize that one-week accelerated Ponseti is at least as effective as standard techniques in achieving the desirable MRI parameters.This is a prospective study of 8 children with severe idiopathic clubfeet (Pirani 6) (4 unilateral and 4 bilateral) treated before the age of three months with one-week accelerated Ponseti technique, as described in a former study with minimum 2-year follow-up. The 8 corrected feet were compared with the 4 unilateral normal feet at clinical and radiological levels using a Pirani scoring system and an MRI, respectively.Clinical results showed that Pirani score was 1.1 in the last follow up in comparison to Pirani 6 pretreatment (p 0.05). MRI results indicated that the malleocalcaneal angle, axial malleocalcaneal index, coronal tibiocalcaneal angle, sagittal talocalcaneal angle, and talar head neck calcaneal rotation showed statistical difference between the two groups (p 0.05). Sagittal malleocalcaneal index, sagittal tibiocalcaneal angle, talar head neck rotation related to talar body, and posterior calcaneal rotation showed no statistical difference between normal feet and clubfeet after correction (p value0.05).One-week accelerated Ponseti technique showed to be as effective and safe as other treatment methods through clinical and MRI follow up data. MRI role was to confirm the efficiency of this innovative accelerated technique, but not used as a routine follow up.

In this work, decoration of the graphene surface with 5 wt. % ZnO nanorods (ZnO NRs), to ensure the potential photocatalytic performance of the formed nanocomposites, is demonstrated. Graphene oxide (GO) was synthesized with Hummer method followed by reduction to give reduced graphene oxide (RGO). The adjustable nano-compositing exhibited long-sought workability not only in in-situ incorporation of nanorods while reduction of graphene oxide (IZG) but also in ex-situ mixing of RGO or GO with the nanorods, (EZG) and (ZGO) respectively. The demineralization of synthetic wastewater has been evaluated by chemical oxygen demand and the obtained nanocomposites possess enhanced photocatalytic activities with 30 % and 35% over pure RGO and GO, respectively. This higher efficiency could be attributed to the synergistic effect between ZnO and the planner structure of graphene sheets which developed unprecedented polycrystalline structure. Also, the results proved that even the RGO or GO have played a dual function in photocatalysis, adsorption, and degradation. Also, the bactericidal effect of the prepared samples was studied against deleterious microorganisms. The findings of this work pave the way for the new generation of highly efficient photocatalysts based graphene with economic attraction and environmental impact., Materials chemistry, Materials science, Nanotechnology, Nanomaterials, Materials synthesis, Food packaging, Environmental pollution, ZnO nanorods, Graphene, Graphene nanocomposites, Graphene photocatalysis, Antibacterial, COD measurements

Introduction. The kidney affects the thyroid gland causing various derangements in its function whenever the kidney is impaired, even with a minor imperfection in its job, and this makes dialysis patients more prone to thyroid disorders with subsequent increase in mortality and morbidity. This study aims to assess the prevalence of thyroid disease (hypo- and hyperthyroidism) among dialysis patients and their associated factors. Methods. This cross-sectional study was conducted in the dialysis unit of An-Najah National University Hospital. 209 dialysis patients (60% were male, 57.6 ± 14.5 years, mean age) meeting our inclusion criteria were tested for thyrotropin (TSH) and free thyroxine (FT4) in addition to routine laboratory tests. Findings. The prevalence of hypothyroidism was assessed as 16.3% (95% CI = 11.29% to 21.3%), overt hypothyroidism was 9.1%, and subclinical hypothyroidism was 7.2%. Subclinical hyperthyroidism prevalence was 1%, and no overt hyperthyroidism cases were reported. We observed no significant association between thyroid state and age, gender, duration of dialysis, or weight. Discussion. Hypothyroidism (both subclinical and overt type) is commonly seen in dialysis patients, and its symptoms are ordinary complains even in euthyroid dialysis patients, and this warrants screening programs and more studies on the efficacy of thyroid hormone supplements.

Several studies have been reported in order to utilize cellulosic based sorbents for lead decontamination from wastewater. However, the research still undergoes so that a highly efficient system is obtained. In the present study, cellulose nanocrystals (CNCs) were successfully decorated during the synthesis of silver (Ag) and zinc oxide (ZnO) nanoparticles, separately. The obtained nanocomposites, Ag/CNC and ZnO/CNC, have been intensively investigated with FTIR, XRD, XPS, and TEM to emphasize the workability of in-situ surface modification of CNCs with Ag and ZnO nanoparticles. The performance of these nanocomposites as effective adsorbents for lead ion Pb(II) has been evaluated under various conditions such as pH, temperature, concentration, and time. Generally, Ag/CNC nanocomposite improved Pb(II) uptake by ~ 22% while ZnO/CNC improved uptake by ~ 60% compared to CNCs. However, the results revealed that 60 min was sufficient time to reach adsorption equilibrium in all cases, which indicates a fast adsorption process. Moreover, ion uptake is enhanced by increasing pH, temperature, and concentration of Pb2+. The kinetic model is pseudo-second-order and the adsorption obeyed Langmuir isotherm (R2 ~ 0.997). The sorbents have revealed more than 94% removal efficiency for pb2+ from wastewater. Furthermore, the developed nanocomposites can be regenerated and reused for three cycles. No doubt, this work paves the way for next generation of functional biosorbants for water treatment applications.

Hyperbranched polyamidoamine (PAMAM) has a high density of surface amino groups. This feature was exploited in the surface modification of κ-carrageenan gel beads for successful protease immobilization. The optimum PAMAM pH was at 2.1 and 9.3. However, treatment of κ-carrageenan gel beads at the higher pH showed re-usability for more than seven successive times. As a result of central composite design optimization, the maximum immobilization yield was obtained by soaking 8 U for 24 h. The comparative thermodynamics studies showed an enhancement in the thermal stability at high temperature for the immobilized protease as well as increased half-life time from 24.06 min to 79.95 min. Also, the D-values increased from 165.03 min to 548.23 min for free and immobilized enzyme, respectively. Moreover, the enzyme stability enhancement for the immobilized protease catalyst was accompanied with a remarkable increase in the enthalpy and in the free energy. Immobilized protease onto Carr-PAMAM gel beads can retain 89% of its initial activity and lost only 11% after 8 weeks of storage at 4 °C. Furthermore, an effective removal of silver from used X-ray film by the immobilized protease was achieved for six repeated cycles.

A sulfonated hyperbranched polyester (HPES-SO3H) was synthesized in order to prepare a proton exchange membrane. The modified hyperbranched polymer was characterized using 1H and 13C NMR and GPC. Hybrids of the modified polymer and polyether sulfone were prepared to incorporate sufficient entanglements and hence increase the mechanical properties of HPES-SO3H. The morphology of the films cast from the hybrids was studied using scanning electron microscopy (SEM), which confirmed the presence of a smooth surface with a controlled pore size. In order to enhance the proton conductivity and improve the mechanical properties of the obtained membrane, different loadings of sodium titanate nanowires (ST NWs), prepared hydrothermally, were added as fillers for the polymer hybrids. Membranes cast from pure polymer hybrids or nanocomposites were used to fabricate a membrane electrode assembly (MEA). It was found that a membrane composed of hyperbranched polyester with a 50% degree of sulfonation and immersed in H2SO4 for 2 h, had an open circuit potential of 0.9 V, compared with Nafion® which showed a potential of 0.85 V. Increasing the immersion time in H2SO4 solution to 12 h led to a sharp increase in current density to a value of 200 mA cm−2 and a power density value of 35 mW cm−2. Moreover, the results reveal that the addition of different amounts of ceramic material to the polymer hybrids has a negative influence on the membrane performance. Nevertheless, high proton conductivity was noticed in samples containing 1 wt% ST NWs. The good water swelling and mechanical properties of the obtained sulfonated polymeric hybrids, along with their cell performance being comparable to commercial membranes, make them promising candidates as proton exchange membranes for fuel cells.

Every year, gastric cancer causes around 819,000 deaths worldwide. The incidence of gastric cancer in the western world is slowly declining, but the prognosis is unpromising. In Germany, the 5-year-survival rate is around 32%, and the average life span after diagnosis is 6 to 9 months. Therapy of gastric cancer patients comprises a gastrectomy and perioperative or adjuvant chemotherapy. However, resistance of gastric cancer cells to these agents is widespread; thus, improved chemotherapeutic approaches are required. Nuclear factor kappa B (NF-κB) transcription factors are associated with anti-apoptosis, carcinogenesis, and chemoresistance, and thus, constitute attractive targets for therapeutic intervention. In immunoblots, we show that ubiquitin specific protease 47 (USP47) promotes β-transducin repeat-containing protein (βTrCP) stability and phosphorylation of RelA. Furthermore, after knockdown of USP47 by RNA interference, we analyzed in gastric cancer cell lines metabolic activity/viability in an MTT assay, and apoptotic cell death by Annexin V staining and poly(ADP-Ribose) polymerase (PARP)-1, caspase 3, and caspase 8 cleavage, respectively. We found that USP47 contributes to cell viability and chemoresistance in NCI-N87 gastric carcinoma cells treated with etoposide and camptothecin. Inhibition of USP47 might be a suitable strategy to downregulate NF-κB activity, and to overcome chemoresistance in gastric cancer.

Graphene (G) is a newcomer material that holds promising properties for many applications. The production of high quality G with a good yield is a long-standing goal for many researchers. This work emphasizes synthesis of dispersed graphene nanoplatelets (DGP) through aqueous dispersion technique in surfactant/water solution with the aid of tip sonication. A chemical method was also used to prepare graphene oxide (GO) and reduced graphene oxide (RGO) for comparison. Elemental analysis revealed the C:O ratio to be 12:1 for DGP but much lower for other graphene structures. Optical characterization of DGP, GO and RGO with UV and Raman spectroscopy confirmed the ideal structure of DGP. Moreover, X-ray diffraction (XRD) revealed the amorphous structure of DGP. Transmission electron microscope (TEM) imaging showed that DGP was composed of a few flat layers, unlike the wrinkled and partially bent multilayered G. Topological study of the DGP surface with scanning electron microscope (SEM) depicted its rough surface with (ra) value of 35 nm, as revealed using an atomic force microscope (AFM). Electrochemical measurements confirmed the higher conductivity of DGP over graphene prepared by chemical method due to lack of structural defects. Its perfect structure facilitates the mobility of charge carriers that makes it preferable in optoelectronic applications.

Titanium oxide nanobelts (TiO2 NBs) are successfully prepared by hydrothermal method in alkaline medium. The surfaces of the obtained NBs were modified to become hydrophobic character. Commercial polystyrene was loaded with different ratios of the aforementioned hydrophobic TiO2 NBs. The casted films were characterized using thermal gravimetric analysis (TGA) and mechanical testing, and their morphology was studied by TEM. The mechanical properties of the prepared PS/TiO2 NBs composite were evaluated and found to be enhanced by increasing the loading of TiO2 NBs. Correspondingly, the antibacterial testing was performed against representative strains of Gram-positive and Gram-negative bac- teria. The results showed that the prepared nanocomposite can be used as packaging materials.

To assess the usefulness of MR defecography in evaluating pelvic floor dysfunction, and to correlate several pelvic organ abnormalities with each other and with patients’ symptoms and characteristics. MR defecographic examinations performed in 3T MRI machine of 95 patients (70 females, 25 males; mean age 48) were retrospectively reviewed. Pelvic organ abnormalities from all three compartments were recorded, including the anorectal junction descent, anterior rectocele, and cystocele. These were graded according to the known HMO system in relation to the pubococcygeal line. The correlation between these different abnormalities and their relation to patient symptoms and characteristics were evaluated. Anorectal junction descent and anterior rectocele were most commonly observed, predominantly manifesting in female patients. Both were associated with abnormalities from all compartments. The middle compartment was the least affected, and its abnormality of uterine/vaginal descent tended to occur in association with the anterior compartment abnormality (cystocele). Anismus was low in incidence, and was not associated with other compartments abnormalities. Both enterocele/peritoneocele and intussusception were uncommon. MR defecography is the modality of choice in assessing pelvic floor dysfunction, because it can neatly show various pelvic organ abnormalities from all compartments in a dynamic fashion, which are frequently coexistent. It can even show clinically silent or unsuspected abnormalities which can impact the management of patients.

Nanoblending hydrophilic nanofillers thoroughly into hydrophobic polymer matrices has long been challenging, especially if involving no pre-functionalization on a 1D ceramic nanomaterial. Here we report a facile approach to fine-tuning of sodium titanate (Na2Ti3O7) nanobelt’s (NB) surface chemistry widely by exchanging the NB’s crystal lattice cations, for successfully nanoblending the low-cost and versatile NBs into the poly(vinyl benzyl chloride) or p(VBC) and the sulfonated form of pVBC’s [or sp(VBC)] matrixes. For the first time, the adjustable nanocompositing showed a long-sought workability in not only in situ radical polymerization of VBC monomer but also ex situ nanoblending of the p(VBC), with the NBs. The resultant nanocomposites possess an unusual surface versatility that can be tailored from being hydrophilic to being hydrophobic by design. This method concludes a generalized and industry-viable approach to mass-producing nanocomposites of many types facilely at low-cost, especially for large scale industries such as packaging materials.

TiO2 nanowires (NWs) were prepared by hydrothermal treatment of TiO2 nanoparticles in alkaline medium, while hyperbranched polyester HPES-OH was prepared by polycondensation. Chemical structure of HPES-OH was confirmed by 1H and 13C NMR spectroscopy, FTIR and the molar mass was determined using gel permeation chromatography (GPC). Nanocomposites based on HPES-OH and TiO2 NWs are synthesized either by ex situ method or by in situ technique. Formation of the nanocomposites and investigation of their morphology were done using transmission electron microscope (TEM), scanning electron microscope (SEM) and X-ray diffraction (XRD). Photocatalytic activity of the synthesized nanocomposites compared to that of pure TiO2-NWs was studied. The chemical oxygen demand (COD) analysis confirmed the mineralization of wastewater via photocatalytic degradation. The results showed that not only photocatalytic activity of nanocomposites was much higher than that of the pure TiO2-NWs, but also the degradation time was reduced to large extent. This result can be attributed to reduction of the crystallite size produced due to the modification reaction. Durability of HPES-OH/TiO2 nanocomposites was investigated and the results confirmed that utilization of the modified TiO2-NWs in the second run was favorable, which suggests that strong adhesion between the NWs and HPES-OH was achieved through the formation of 2D structure.

Lead is a one of the most hazardous heavy metals that requires a good sorbent in order to be removed from the decontaminated water. Herein, titanium dioxide nanowires were hydrothermally synthesized from titanium dioxide nanoparticles. The nanowires obtained were characterized by transmission electron microscope (TEM), Fourier Transform Infrared (FTIR), X-ray Diffraction (XRD), and Surface area (BET). The nanowires produced were utilized as an effective sorbent for lead ions from synthetic waste water. The optimized conditions in terms of pH, concentration and time effects have been intensively investigated. While recovery, titanium dioxide nanowires showed better workability for lead elimination after the second run. The antimicrobial activity of the prepared nanowires was also discussed against deleterious microbes. Thus, titanium dioxide nanowires are considered as a green and an alternative candidate for water remediation purposes thanks to the intrinsic duel functions, adsorbent and antimicrobial agent.