New synergic behavior is always inspiring scientists toward the formation of nanocomposites aiming at getting advanced materials with superior performance and/or novel properties. Carbon nanotubes ...(CNT), graphene, fullerene, and graphite as carbon-based are great fillers for polymeric materials. The presence of these materials in the polymeric matrix would render it several characteristics, such as electrical and thermal conductivity, magnetic, mechanical, and as sensor materials for pressure and other environmental changes. This review presents the most recent works in the use of CNT, graphene, fullerene, and graphite as filler in different polymeric matrixes. The primary emphasis of this review is on CNT preparation and its composites formation, while others carbon-based nano-fillers are also introduced. The methods of making polymer nanocomposites using these fillers and their impact on the properties obtained are also presented and discussed.
Egypt is among the world's largest producers of sugarcane. This crop is of great economic importance in the country, as it serves as a primary source of sugar, a vital strategic material. The ...pre-cutting planting mode is the most used technique for cultivating sugarcane in Egypt. However, this method is plagued by several issues that adversely affect the quality of the crop. A proposed solution to these problems is the implementation of a sugarcane-seed-cutting device, which incorporates automatic identification technology for optimal efficiency. The aim is to enhance the cutting quality and efficiency of the pre-cutting planting mode of sugarcane. The developed machine consists of a feeding system, a node scanning and detection system, a node cutting system, a sugarcane seed counting and monitoring system, and a control system. The current research aims to study the pulse widths (PW) of three-color channels (R, G, and B) of the RGB color sensors under laboratory conditions. The output PW of red, green, and blue channel values were recorded at three color types for hand-colored nodes black, red, and blue, three speeds of the feeding system 7.5 m/min, 5 m/min, and 4.3 m/min, three installing heights of the RGB color sensors 2.0 cm, 3.0 cm, and 4.0 cm, and three widths of the colored line 10.0 mm, 7.0 mm, and 3.0 mm. The laboratory test results s to identify hand-colored sugarcane nodes showed that the recognition rate ranged from 95% to 100% and the average scanning time ranged from 1.0 s to 1.75 s. The capacity of the developed machine ranged up to 1200 seeds per hour. The highest performance of the developed machine was 100% when using hand-colored sugarcane stalks with a 10 mm blue color line and installing the RGB color sensor at 2.0 cm in height, as well as increasing the speed of the feeding system to 7.5 m/min. The use of IoT and RGB color sensors has made it possible to get analytical indicators like those achieved with other automatic systems for cutting sugar cane seeds without requiring the use of computers or expensive, fast industrial cameras for image processing.
Construction of a fast, easy and sensitive neurotransmitters-based sensor could provide a promising way for the diagnosis of neurological diseases, leading to the discovery of more effective ...treatment methods. The current work is directed to develop for the first time a flexible Surface-Enhanced Raman Spectroscopy (SERS) based neurotransmitters sensor by using the ultrasonic-assisted fabrication of a new set of epoxy resin (EPR) nanocomposites based on graphene nanosheets (GNS) using the casting technique. The perspicuous epoxy resin was reinforced by the variable loading of GNS giving the general formula GNS/EPR
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. The designed products have been fabricated in situ while the perspicuous epoxy resin was formed. The expected nanocomposites have been fabricated using 3%, 5%, 10%, 15% and 20% GNS loading was applied for such fabrication process. The chemical, physical and morphological properties of the prepared nanocomposites were investigated by using Fourier transforms infrared spectroscopy, X-ray diffraction, Thermogravimetric analysis, Differential Thermal gravimetry, and field emission scanning electron microscopy methods. The GNS/EPR
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nanocomposites were decorated with a layer of gold nanoparticles (Au NPs/GNS/EPR) to create surface-enhanced Raman scattering hot points. The wettability of the Au NPs/GNS/EPR was investigated in comparison with the different nanocomposites and the bare epoxy. Au NPs/GNS/EPR was used as a SERS-active surface for detecting different concentrations of dopamine with a limit of detection of 3.3 µM. Our sensor showed the capability to detect low concentrations of dopamine either in a buffer system or in human serum as a real sample.
In this study, the simple and sensitive enzymeless electrochemical gamma-aminobutyric acid (GABA) neurotransmitter sensor was developed based on the graphene oxide modified Au electrode with the ...ligand. A mixture of ortho-phthalaldehyde (OPA) and an alkylthiol reagent is used as a ligand to interact with GABA, which became an electrochemical active compound. The sensor consisted of a graphene oxide modified Au electrode. The effect of pH variation on the electrochemical signal of GABA was investigated; a good electrochemical response was observed in neutral- and slightly alkaline- medium, i.e. the value of the pH for the physiological-like media. The proposed sensor detected the wide range concentration of GABA from 250 nmol L−1 to 100 μmol L−1 with a detection limit of 98 nmol L−1. And the sensor could detect a mixture of GABA and Glutamate, and GABA in complex solutions including human serum and urine, which indicated the capability of the sensor to detect GABA in complicated matrixes. The proposed sensor system can be applied to detect neurotransmitters in the brain and be used in the field of diagnosis and treatment of neurological disorders.
•OPA/2ME was prepared as ligand for GABA detecting.•Graphene oxide modified Au electrode has fabricated as working electrode.•Enzymeless electrochemical biosensor was reported for GABA detection.•The modified electrode showed good durability (96.4% after 100 cycles).
Lipases are extensively utilized industrial biocatalysts that play an important role in various industrial and biotechnological applications. Herein, polyacrylonitrile (PAN) was treated with ...hexamethylene diamine (HMDA) and activated by glutaraldehyde, then utilized as a carrier support for
lipase. In this regard, the morphological structure of modified PAN before and after the immobilization process was evaluated using FTIR and SEM analyses. The immobilized lipase exhibited the highest activity at pH 8.0, with an immobilization yield of 81% and an activity of 91%. The optimal pH and temperature for free lipase were 7.5 and 40 °C, while the immobilized lipase exhibited its optimal activity at a pH of 8.0 and a temperature of 50 °C. After recycling 10 times, the immobilized lipase maintained 76% of its activity and, after 15 reuses, it preserved 61% of its activity. The lipase stability was significantly improved after immobilization, as it maintained 76% of its initial activity after 60 days of storage. The calculated Km values were 4.07 and 6.16 mM for free and immobilized lipase, and the Vmax values were 74 and 77 μmol/mL/min, respectively. These results demonstrated that synthetically modified PAN is appropriate for immobilizing enzymes and has the potential for commercial applications.
This study reports the first analytical study conducted on samples of fired bricks, bedding mortar and plaster layers collected from the catacombs of Ptolemy IV Philopator at Karnak temples, Upper ...Egypt. These unique constructions comprise three-level rectangular vaulted brick shrines that lined up in three passages. The microscopic particularities of the samples were assessed by digitalized optical handheld microscope, while the petrographic analysis was depicted by polarized light microscope. X-ray diffractometer was used to analyse some brick, mortar and plaster samples. The morphological description and microchemical analysis, on various points in the samples, were attained via the field-emission scanning electron microscope with an energy-dispersive X-ray spectrometer. Further, the molecular and vibrational attributions of some fragments and pigment grains were recognized using Fourier transform infrared spectrometer and Raman microspectrometer (µ-Raman). Results showed that the studied bricks were fired at low temperature using poor-calcium clays. The cross-sectional observation on the plaster layers defined three layers, which are mainly made up of calcium carbonate (calcite). Minerals of quartz, rutile, plagioclase feldspars and calcium silicate were identified, in varying proportions, in the studied plasters. Pigments as Egyptian blue, yellow ochre and red ochre were characterized along the plaster layers. Likely, the microscopic examination and the molecular analysis of the samples disclosed that “fresco” technique was used to decorate the catacombs.
Recently, obesity witnessed a dramatic increase and its related comorbidities have grown. Bariatric surgeries were developed to reduce weight. However, all techniques had their advantages and ...shortages. In this work, we aimed to assess our new modification of combining sleeve gastrectomy with Roux en-y bypass for the management of obesity, hoping to gain benefits from both techniques to increase the excess bodyweight loss (EBW%).
The study was a prospective observational study on 23 Morbidly obese patients. The study was held from January 2020 to April 2022. The recruited patients were submitted to detailed clinical assessment and investigations to check fitness for surgery. Besides operative data, any intra- or post-operative complications were recorded. Each patient was followed up for at least one year. The follow-up visits were scheduled at regular intervals (one week, one month, six months, and twelve months).
The mean operative time was 113.91 minutes (65-150). No intraoperative complications or conversion. There was intraluminal bleeding in one patient within 48 hours postoperatively with successful conservative management. There was a complete cure of diabetes mellitus (DM) for 5, 2, and 3 patients and antidiabetic drugs were reduced for 64.3%, 21.43%, and 7.14% at 1, 6, and 12 months follow up respectively. Hypertension was cured in 1,1,2 patients, and antihypertensives were reduced for 2,1,1 patient, at 1, 6, and 12 months follow up respectively. EWL% was 14.4%, 40.78%, and 73.74% at 1,6,12 months follow up respectively. Hemoglobin concentration and ionized calcium improved over time. Finally, serum albumin at 1, 6, and 12 months follow-up was 3.64, 3.58, 3.78 g/dL respectively.
New modifications of combining LSG and LRYGB have shown to be safe and effective procedures. In addition, it is associated with minimal postoperative nutritional complications and permits complete visualization of the biliary system using endoscopy.
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•A hand-operating and easy-to-make synthesis of mesoporous sensors was achieved.•The synthesized sensors showed evidence of highly sensitive detection of Au(III).•This process shown ...functionality in terms of selectivity and reversibility.•Extraction of gold ions from E-waste was evident.
Platinum group metals have gained significant interest due to their unique characteristics, which make them the main constituents in advanced applications. In this work, we introduce new pH-dependent optical mesocaptors for the colorimetric monitoring and separation of Au(III) from E-waste leach liquors without a preconcentration process. The mesoporous silica nanospheres are fabricated via simple, reproducible, and low-cost procedures. The optical mesocaptor is designed via indirect immobilization of thiazole yellow G (TYG) and amacid yellow M (AYM) chromogenic probes onto mesoporous nanostructured scaffolds. The silanol groups in the mesopores of silica surface robustly anchored dilauryl dimethyl ammonium bromide (DDAB) linker to induce the interactions with the TYG and AYM chelates, thereby leading to the fashioning of a stable optical mesocaptors without releasing of the chelates throughout adsorption and sensing assays. The finding provides evidence of the capability of the synthesized decorated new nanostructured sensor shows excellent sensitivity toward Au(III) with a limit of detection (LOD) as low as 1.16 µg L−1. Furthermore, the new sensors were able to selectively detect Au(III) in solution with multi ions components.
Thiazol-based molecules have practically infinite biological implementation. Today, there are many medical applications for compounds containing the thiazole moiety owing to their presence in most ...clinically applied anticancer drugs, such as dasatinib, dabrafenib, ixabepilone, patellamide A and epothilone. In this study, the polycondensation, of a new group of thiazole-containing polyamides with the formulas PA
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was carried out by the interaction of 2-aminothiazole diphenyl sulfide and variable diacid chlorides in dimethyl formamide in the presence of potassium carbonate anhydrous as a catalyst. Fourier transform-infrared spectroscopy (FTIR) was initially used to figure out the PA
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structures, which were further characterized using solubility, gel permeation chromatography (GPC), X-ray diffraction analyses (XRD) and scanning electron microscopy (SEM). The solubility results revealed that the presence of heteroaromatic thiazole ring units and sulfur content in the polyamides main chain, made the solubility easier as it increases the chain packing distance. From the values of average molecular weight, it was clear that all synthesized polyamides have almost the same chain length which ranged from 37,561.80 to 39,827.66. Moreover, the thermogravimetric analysis (TGA) confirm that PA
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were thermally stable even at high temperatures especially the polyamides which were synthesized from aromatic diacid chlorides. Furthermore, the newly synthesized polyamides were investigated for their antimicrobial properties against different species of Gram-positive and Gram-negative bacteria and also against different fungi. The results revealed that compound PA
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showed the highest antibacterial activity. Also, their inhibitory activity against breast carcinoma cells (MCF-7 cell line) and colon carcinoma cells (HCT cell line) was evaluated. It was clear that there was an enhancement in the anticancer activity for the synthesized polyamides owing to the presence of the thiazole moiety as well as sulfur linkage. According to the results of the 50% inhibitory concentration (IC50), the synthesized polymers were found to be more active against the MCF-7 cell line than the HCT cell line.
Androgenetic alopecia (AGA) is a common and benign cause of chronic hair loss that affects both males and females. Platelet-rich plasma (PRP) is a safe and minimally invasive technique with promising ...outcomes in patients with AGA, alongside other therapeutics use. The currently available data in the literature assures that the rate of side effects is low but includes infection and localized reaction (Stevens and Khetarpal, Feb. 2019) 1. This article describes a case of herpes zoster ophthalmicus (HZO) following PRP treatment for androgenic alopecia, while shedding light on the importance of respecting the guidelines when injecting PRP therapy to ensure a safe outcome with no complications.
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