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1.
Nanomaterials (Basel) ; 13(23)2023 Nov 21.
Article in English | MEDLINE | ID: mdl-38063681

ABSTRACT

5Ni/MgO and 5Ni/γAl2O3 are pronounced in the line of cheap catalyst systems for the dry reforming of methane. However, the lower reducibility of 5Ni/MgO and the significant coke deposition over 5Ni/γAl2O3 limit their applicability as potential DRM catalysts. The mixing capacity of MgO and Al2O3 may overcome these limitations without increasing the catalyst cost. Herein, a 5Ni/xMg(100 - x)Al (x = 0, 20, 30, 60, 70, and 100 wt. %) catalyst system is prepared, investigated, and characterized with X-ray diffraction, surface area and porosity measurements, H2-temperature programmed reduction, UV-Vis-IR spectroscopy, Raman spectroscopy, thermogravimetry, and transmission electron microscopy. Upon the addition of 20 wt. % MgO into the Al2O3 support, 5Ni/20Mg80Al is expanded and carries both stable Ni sites (derived through the reduction of NiAl2O4) and a variety of CO2-interacting species. CH4 decomposition at Ni sites and the potential oxidation of carbon deposits by CO2-interacting species over 5Ni/20Mg80Al results in a higher 61% H2-yield (against ~55% H2-yield over 5Ni/γAl2O3) with an excellent carbon-resistant property. In the major magnesia support system, the 5Ni/60Mg40Al catalyst carries stable Ni sites derived from MgNiO2 and "strongly interacted NiO-species". The H2-yield over the 5Ni/60Mg40Al catalyst moves to 71%, even against a high coke deposition, indicating fine tuning between the carbon formation and diffusion rates. Ni dispersed over magnesia-alumina with weight ratios of 7/3 and 3/7 exhibit good resistance to coke. Weight ratios of 2/8 and 7/3 contain an adequate amount of reducible and CO2-interactive species responsible for producing over 60% of H2-yield. Weight ratio 6/4 has a proper coke diffusion mechanism in addition to achieving a maximum of 71% H2-yield.

3.
Heliyon ; 9(7): e17050, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37483767

ABSTRACT

Repairing significant bone defects remains a critical challenge, raising the clinical demand to design novel bone biomaterials that incorporate osteogenic and angiogenic properties to support the regeneration of vascularized bone. Bioactive glass scaffolds can stimulate angiogenesis and osteogenesis. In addition, natural or synthetic polymers exhibit structural similarity with extracellular matrix (ECM) components and have superior biocompatibility and biodegradability. Thus, there is a need to prepare composite scaffolds of hydrogels for vascularized bone, which incorporate to improve the mechanical properties and bioactivity of natural polymers. In addition, those composites' 3-dimensional (3D) form offer regenerative benefits such as direct doping of the scaffold with ions. This review presents a comprehensive discussion of composite scaffolds incorporated with BaG, focusing on their effects on osteo-inductivity and angiogenic properties. Moreover, the adaptation of the ion-doped hydrogel composite scaffold into a 3D scaffold for the generation of vascularized bone tissue is exposed. Finally, we highlight the challenges and future of manufacturing such biomaterials.

4.
J Taibah Univ Med Sci ; 18(1): 61-64, 2023 Feb.
Article in English | MEDLINE | ID: mdl-35875171

ABSTRACT

Background: Critically ill COVID-19 patients have an elevated risk of experiencing hypercoagulable conditions. Currently, many COVID-19 patients have been administered anticoagulation or antiplatelet therapies to lower the risk of systematic thrombosis. Iliopsoas hematoma is a potentially fatal and rare complication of bleeding disorders or anticoagulation therapy which sometimes grows to become clinically significant. The main purpose of this case review is to emphasize the importance of diagnosing iliopsoas hematomas and the possibility of antiplatelet contribution to its development. Case Presentation: We are reporting a rare presentation of non-traumatic iliopsoas hematoma in a non-anticoagulated patient. The patient is a 59-year-old male, with known type-2 diabetes, on oral hypoglycemic medications, 3-weeks post-COVID-19. He had started aspirin 81 mg orally, once daily, to prevent thrombotic events associated with COVID 19 infection, with no anticoagulant use and no other medications. He came in through the ED, presenting with two weeks history of progressive right lower limb weakness in which an iliopsoas hematoma diagnosis was confirmed based on radiological investigation. Conclusion: The possibility of iliopsoas hematoma should be considered in non-anticoagulated patients with no inherited or acquired coagulation disorders presenting with limb weakness. The link between antiplatelet use in a COVID-19 patient and the development of soft tissue bleeding (e.g., iliopsoas hematoma) must be studied further.

5.
Polymers (Basel) ; 14(9)2022 Apr 22.
Article in English | MEDLINE | ID: mdl-35566879

ABSTRACT

There is a demand for long afterglow composites due to their potential applications in nighttime signal boards, sensors, and biomedical areas. In this study, Polypropylene (PP)/strontium aluminate-based composites [SrAl2O4:Eu2+/Dy3+ (SAO1) and Sr4Al14O25: Eu+2, Dy+3 (SAO2)] with maleic anhydride grafted PP compatibilizer (PRIEX) were prepared, and their auto-glowing properties were examined. After UV excitation at 320 nm, the PP/5PRIEX/SAO1 composites showed green emission at 520 nm, and blue emission was observed for PP/5PRIEX/SAO2 around 495 nm. The intensity of phosphorescence emission and phosphorescence decay was found to be proportional to the filler content (SAO1 and SAO2). The FTIR analysis excluded the copolymerization reaction between the SAO1 and SAO2 fillers and the PP matrix during the high-temperature melt mixing process. The SAO1 and SAO2 fillers decreased the overall crystallinity of the composites without affecting the Tm and Tc (melting and crystallization temperature) values. The thermal stability of the composites was slightly improved with the SAO1 and SAO2 fillers, as seen from the TGA curve. Due to the plasticizing effect of the compatibilizer and the agglomeration of the SAO1 and SAO2 fillers, the tensile modulus, tensile strength, and storage modulus of the composites was found to be decreased with an increase in the SAO1 and SAO2 content. The decreasing effect was more pronounced, especially with the bulk-sized SAO2 filler.

6.
Polymers (Basel) ; 14(3)2022 Feb 07.
Article in English | MEDLINE | ID: mdl-35160620

ABSTRACT

Previously, we reported that amorphous poly(ethylene terephthalate) (PET) filled with irregular nodular aluminium (Al) particles gave simultaneous increases in tensile modulus, tensile strength, and impact resistance, which is unusual for materials. Here, we investigated the effect of the particle shape and size by using nano-platelet Al. The Al nano-platelets had a thickness higher than graphenes and clays, but lower than mica and talc, and due to their large widths, they had high aspect ratios. Due to the ductility of Al, the platelets maintained the high aspect ratio and did not snap during injection moulding. In addition to avoiding the usual drop in tensile strength and impact, the composites with nano Al platelets gave an unusually high flexural modulus (8 GPa), which was almost double that attained practically with talc, mica, and graphene. This was because of the high tendency of the Al nano platelets to become oriented during moulding. The Al-PET composite would be a more cost-and-performance effective combination for making conductive composites. The Al is a cheaper material than graphene, surface treatment for adhesion (to PET) is unnecessary, and dispersion issues, such as exfoliation and de-aggregation, are not a problem.

7.
Materials (Basel) ; 15(3)2022 Feb 01.
Article in English | MEDLINE | ID: mdl-35161084

ABSTRACT

In this work, HDPE/strontium aluminate-based auto glowing composites (SrAl2O4: Eu, Dy (AG1) and Sr4Al14O25: Eu, Dy (AG2)) were prepared, and their phosphorescence studies were conducted. In HDPE/AG1 composites, the green emission was observed at ~500 nm after the UV excitation at 320 nm. The HDPE/AG2 has a blue emission at ~490 nm and, in both cases, the intensity of emission is proportional to the AG1 and AG2 content. The DSC data show that the total crystallinity of both the composites was decreased but with a more decreasing effect with the bulky AG2 filler. The melting and crystallization temperatures were intact, which shows the absence of any chemical modification during high shear and temperature processing. This observation is further supported by the ATR-FTIR studies where no new peaks appeared or disappeared from the HDPE peaks. The tensile strength and modulus of HDPE, HDPE/AG1, and HDPE/AG2 composites were improved with the AG1 and AG2 fillers. The rheological studies show the improvement in the complex viscosity and accordingly the storage modulus of the studied phosphorescent HDPE composites. The SEM images indicate better filler dispersion and filler-matrix adhesion, which improves the mechanical characteristics of the studied HDPE composites. The ageing studies in the glowing composites show that there is a decrease in the intensity of phosphorescence emission on exposure to drastic atmospheric conditions for a longer period and the composites become more brittle.

8.
Polymers (Basel) ; 13(9)2021 Apr 22.
Article in English | MEDLINE | ID: mdl-33922265

ABSTRACT

A tremendous potential has been observed in the designing of long afterglow materials for sensing, bioimaging, and encryption applications. In this study, two different strontium aluminate-based luminescent materials; SrAl2O4: Eu, Dy (S1), and Sr4Al14O25: Eu, Dy (S2) were melt-mixed with polypropylene (PP) matrix, and the phosphorescence properties were evaluated. After excitation at 320 nm, the PP/S1 composite exhibited a green emission and the PP/S2 generated a blue emission at 520 nm and 495 nm, respectively. The emission spectra intensity increased by increasing the content of these luminescent fillers. The attenuated total reflection-Fourier transform infrared (ATR-FTIR) experiments show that no chemical reaction occurred during the melt-mixing process. The differential scanning calorimetry (DSC) results revealed that the total crystallinity of the composites reduced by increasing the amount of the fillers; however, no changes in the temperature of melting (Tm) and crystallization (Tc) of PP were observed. Both fillers improved the impact strength of the composites, but the tensile strength (TS) and modulus (TM) decreased. Poly (ethylene glycol) dimethyl ether (P) plasticizer was used to improve the filler-matrix interaction and its dispersion; nevertheless, it adversely affected the intensity of the luminescence emissions.

9.
J Ethnopharmacol ; 270: 113813, 2021 Apr 24.
Article in English | MEDLINE | ID: mdl-33444719

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Medicinal plants have been used by indigenous people across the world for centuries to help individuals preserve their wellbeing and cure diseases. Annona muricata L. (Graviola) which is belonging to the Annonaceae family has been traditionally used due to its medicinal abilities including antimicrobial, anti-inflammatory, antioxidant and cancer cell growth inhibition. Graviola is claimed to be a potential antitumor due to its selective cytotoxicity against several cancer cell lines. However, the metabolic mechanism information underlying the anticancer activity remains limited. AIM OF THE STUDY: This study aimed to investigate the effect of ionic liquid-Graviola fruit pulp extract (IL-GPE) on the metabolomics behavior of colon cancer (HT29) by using an untargeted GC-TOFMS-based metabolic profiling. MATERIALS AND METHODS: Multivariate data analysis was used to determine the metabolic profiling, and the ingenuity pathway analysis (IPA) was used to predict the altered canonical pathways after treating the HT29 cells with crude IL-GPE and Taxol (positive control). RESULTS: The principal components analysis (PCA) identified 44 metabolites with the most reliable factor loading, and the cluster analysis (CA) separated three groups of metabolites: metabolites specific to the non-treated HT29 cells, metabolites specific to the treated HT29 cells with the crude IL-GPE and metabolites specific to Taxol treatment. Pathway analysis of metabolomic profiles revealed an alteration of many metabolic pathways, including amino acid metabolism, aerobic glycolysis, urea cycle and ketone bodies metabolism that contribute to energy metabolism and cancer cell proliferation. CONCLUSION: The crude IL-GPE can be one of the promising anticancer agents due to its selective inhibition of energy metabolism and cancer cell proliferation.


Subject(s)
Annona/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Fruit/chemistry , Ionic Liquids/pharmacology , Metabolome/drug effects , Plant Extracts/pharmacology , Cell Proliferation/drug effects , Colonic Neoplasms/metabolism , Colonic Neoplasms/pathology , HT29 Cells , Humans , Paclitaxel/pharmacology , Principal Component Analysis
10.
Polymers (Basel) ; 12(9)2020 Sep 08.
Article in English | MEDLINE | ID: mdl-32911602

ABSTRACT

Metal-plastic composites have the potential to combine enhanced electrical and thermal conductivity with a lower density than a pure metal. The drawback has often been brittleness and low impact resistance caused by weak adhesion between the metal filler and the plastic. Based on our observation that aluminum foil sticks very strongly to poly(ethylene terephthalate) (PET) if it is used as a backing during compression moulding, this work set out to explore PET filled with a micro and a nano aluminum (Al) powder. In line with other composites using filler particles with low aspect-ratio, the tensile modulus increased somewhat with loading. However, unlike most particle composites, the strength did not decrease and most surprisingly, the Izod impact resistance increased, and in fact more than doubled with certain compositions. Thus, the Al particles acted as a toughening agent without decreasing the modulus and strength. This would be the first case where addition of a metal powder to a plastic increased the modulus and impact resistance simultaneously. The Al particles also acted as nucleating agents but it was not sufficient to make PET crystallize as fast as the injection moulding polyester, poly(butylene terephthalate) (PBT).

11.
Sci Total Environ ; 619-620: 311-318, 2018 Apr 01.
Article in English | MEDLINE | ID: mdl-29154049

ABSTRACT

The application of biochar (BC) as a filler in polymers can be viewed as a sustainable approach that incorporates pyrolysed waste based value-added material and simultaneously mitigate bio-waste in a smart way. The overarching aim of this work was to investigate the electrical, mechanical, thermal and rheological properties of biocomposite developed by utilizing date palm waste-derived BC for the reinforcing of polypropylene (PP) matrix. Date palm waste derived BC prepared at (700 and 900°C) were blended at different proportions with polypropylene and the resultant composites (BC/PP) were characterized using an array of techniques (scanning electron microscope, energy-dispersive X-ray spectroscopy and Fourier transform infra-red spectroscopy). Additionally the thermal, mechanical, electrical and rheological properties of the BC/PP composites were evaluated at different loading of BC content (from 0 to15% w/w). The mechanical properties of BC/PP composites showed an improvement in the tensile modulus while that of electrical characterization revealed an enhanced electrical conductivity with increased BC loading. Although the BC incorporation into the PP matrix has significantly reduced the total crystallinity of the resulted composites, however; a positive effect on the crystallization temperature (Tc) was observed. The rheological characterization of BC/PP composites revealed that the addition of BC had minimal effect on the storage modulus (G') compared to the neat (PP).

12.
Int J Health Sci (Qassim) ; 9(3): 315-31, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26609296

ABSTRACT

OBJECTIVES: The present study aims at assessing nursing and sanitation staff knowledge and practice regarding Healthcare Waste (HCW) management before and after the implementation of an educational intervention program at the main hospitals of the White Nile State in Sudan. METHODOLOGY: Quasi-experimental study design was applied to assess the impact of an intervention program on knowledge and practice regarding HCW management. The same questionnaire used in the pre-test was used immediately after the end of the intervention program and then again three months later for a second post-test. RESULTS: The results showed that the majority of nursing and sanitation staff had fair knowledge regarding HCW management before the educational intervention program (17% good, 58% fair, and 25% poor). After implementation of the educational program, the majority had good knowledge (56% good, 34% fair, and 10% poor) in the immediate post-test, and also in the post-test three months later (59% good, 35% fair, and 6% poor). More than half the nursing and sanitation staff had fair level of practice before the educational intervention program (42% good, 55% fair, and 3% poor). After the implementation of the intervention program, the immediate post-test showed a similar result (45% good, 54% fair, and 1% poor), while the post-test three months later showed that the majority demonstrated good practice level (55% good, 42% fair, and 3% poor). CONCLUSION: The nursing and sanitation staff at the main hospitals of the White Nile State in Sudan recorded significant improvement in their knowledge and practice with regard to HCW management immediately after the educational intervention program and three months later.

13.
J Egypt Public Health Assoc ; 88(1): 14-8, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23528527

ABSTRACT

BACKGROUND: Sudan is classified among countries with a high hepatitis B surface antigen (HBsAg) endemicity of more than 8%. Cross-sectional studies have showed a marked increase in the prevalence of occult hepatitis B infection (OBI) in patients with cirrhosis or hepatocellular carcinoma. In terms of OBI infectivity by transfusion, it is largely unknown whether residual risk estimates translate into true rates of infection. AIM: The current study aimed to determine the frequency of OBI among blood donors in Sudan. MATERIALS AND METHODS: This study was carried out during the period between 2011 and 2012. It included 100 HBsAg-negative blood donors who attended the Central Blood Bank in Sudan. Sera collected from all donors were tested for HBsAg, antibodies against hepatitis B core antigen (anti-HBc), antibodies against hepatitis Be antigen (anti-HBe), and antibodies against hepatitis B surface antigen (anti-HBs) by enzyme-linked immunosorbant assay. Anti-HBc-positive patients were tested for hepatitis B virus (HBV)-DNA. RESULTS: The anti-HBc was detected in 42% of the blood donors, among whom 90.5% were positive for HBV-DNA. Two main profiles have been detected, namely, the presence of the three genes (S, C, and X genes) together in 35.7% of the blood donors or the presence of the X gene in addition to the core gene. CONCLUSION AND RECOMMENDATIONS: With the use of HBsAg as the sole detection marker for HBV, there is a danger of HBV transmission through blood transfusion. Anti-HBc testing should be added to the routine blood donor screening test if occult hepatitis B is to be diagnosed.


Subject(s)
Blood Donors , Hepatitis B virus , Cross-Sectional Studies , DNA, Viral/blood , Hepatitis B/diagnosis , Hepatitis B virus/genetics , Humans , Liver Neoplasms , Sudan
14.
Int J Health Sci (Qassim) ; 6(1): 63-71, 2012 Jan.
Article in English | MEDLINE | ID: mdl-23267305

ABSTRACT

OBJECTIVE: Breast cancer is a major cause of morbidity and mortality in women worldwide. In Sudan, it is the most commonly diagnosed cancer. This study assesses the prevalence of BRCA1 and BRCA2 mutations among female students with a family history of breast cancer, in secondary schools of Marawi Locality, Northern State, Sudan. METHODS: From a survey of 2370 students, 67 cases (47 with family history and 20 controls) were analyzed for BRCA1 and BRCA2 mutations with a single-stranded conformation polymorphism (SSCP) mutation detection method applied to peripheral blood. Eighteen subjects knew of first degree female relatives with breast cancer, 23 with second degree female family members affected and 6 with related male sufferers. Twenty randomly selected girls from the remainder of the survey population with no known family history were also tested. RESULTS: The breast cancer susceptibility genes BRCA1 and BRCA2 accounted, respectively, for 1.21% of responders or 51% of those claiming a family history. Mutations were found in 20% of the group selected with no family history. Only 2 BRCA 2 mutations were found, both in girls with no known afflicted relatives. Six girls knew of male relatives with breast cancer; five of these girls carried mutant BRCA 1. Most of the BRCA1- mutations located to exon 11 fragments 11.9 and 11.1. CONCLUSION: The study indicates a high prevalence of genetically associated breast cancer in the Marawi locality suggesting a need to focus on the two mutation sites in developing screening protocols for at least this area of Sudan.

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