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1.
Heliyon ; 10(6): e27782, 2024 Mar 30.
Article in English | MEDLINE | ID: mdl-38524620

ABSTRACT

An improved mutual coupling compensation in circularly polarized (CP) multi-input multi-output (MIMO) dielectric resonator antenna (DRA) is presented in this paper. Using trimming approach, the mutual coupling (MC) between closely spaced DRA units at 0.3λ has been significantly reduced while axial ratio performance has been maintained. Mutual coupling reduction is obtained by trimming the DRA to ensure low mutual coupling below -20dB. The exclusive features of the proposed MIMO DRA include wide impedance matching bandwidth (BW), triple band circular polarization, and suppressed MC between the radiating elements. The impedance bandwidth matches perfectly with a triple band's 3 dB axial ratio (AR). It is designed with characteristic mode analysis with good agreement of the measurement that has been obtained. Using the probe feed method, the DRA and patch strip are coupled together to allow bandwidth widening of the pro-posed DRA. An impedance bandwidth of 34% at a lower frequency to around 2% at a higher frequency was achieved in all resonance frequencies. Thus, we refer to our newly designed DRA as a proposed method for effectively reducing the mutual coupling between DRAs. Additionally, the 3 dB AR bandwidth matched at 3.3 GHz, 4.6 GHz, and 6.3 GHz with a percentage of 11.66%, 3.04%, and 2.22% obtained at the three different frequencies. Note that the proposed DRA exhibits low mutual coupling (below -20 dB) at the targeted frequencies, which is suitable for better signal reception for MIMO applications. By computing, the metrics envelop correlation coefficient, diversity gain, channel capacity loss, and total active reflection coefficient, the MIMO performance of the proposed antenna is verified. The experiments show a close result between simulated and computed validation of the proposed DRA.

2.
Eur J Surg Oncol ; 50(3): 108019, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38359725

ABSTRACT

BACKGROUND: Mediastinal Yolk sac tumors (YST) are rare and highly malignant extragonadal germ cell tumors with rapid growth and early metastases. We sought to conduct a meta-analysis of published case reports/case series to compare differences in survival, demographics, and treatment modalities between adult and pediatric patients with YST. METHODS: Ovid Embase, Cochrane, and Ovid Medline databases were searched for primary mediastinal pure YST cases. The primary outcome was overall survival (OS). Log-rank and Cox regression were used. This study is registered on PROSPERO (CRD42022367586). RESULTS: Among 846 studies, 87 met our inclusion criteria including 130 patients (Adults: 90 and Pediatrics: 40). About 41.5% of the patients were from the United States. The median age was 23.0 (Q1-Q3: 17.0-30.0), 88.5% were males, and (32.3%) were Asian. Stage II represented almost 40%. AFP was elevated in 96.9%. Respiratory distress was the presenting symptom in 65.4%. Chemotherapy, radiotherapy, and surgery were utilized in 84.6, 23.1, and 64.7% respectively. Median OS was 24 months (Adults: 23 months, Pediatrics: 25 months, P = 0.89). 3- and 5-year OS were 34.4% and 22.9% in adults and 41.5% and 41.5% in pediatrics, respectively. On multivariate analysis, anterior location of tumors, receipt of chemotherapy, and undergoing surgery were associated with better OS. CONCLUSION: Primary mediastinal YSTs are rare, but lethal neoplasms. Our meta-analysis showed that mediastinal YSTs mimic other non-seminomatous mediastinal GCTs in terms of clinical characteristics and available treatment options. Early diagnosis, neoadjuvant chemotherapy, and surgical resection are the key points for effective management and improved outcomes.


Subject(s)
Endodermal Sinus Tumor , Mediastinal Neoplasms , Neoplasms, Germ Cell and Embryonal , Male , Adult , Humans , Child , Young Adult , Female , Endodermal Sinus Tumor/drug therapy , Endodermal Sinus Tumor/pathology , Mediastinal Neoplasms/therapy , Mediastinal Neoplasms/pathology , Mediastinum/pathology , Neoadjuvant Therapy
4.
Cancers (Basel) ; 15(6)2023 Mar 20.
Article in English | MEDLINE | ID: mdl-36980734

ABSTRACT

Hypercoagulability is strongly associated with cancer and may result in non-bacterial thrombotic endocarditis (NBTE). The aim of our meta-analysis was to explore the demographics and characteristics of this condition in cancer. Databases were systematically searched. The outcomes were to identify the annual trend in premortem diagnosis among the entire cohort and different subgroups and to identify differences in characteristics and survival in the considered population. A total of 121 studies with 144 patients were included. The proportion of marantic endocarditis associated with lung cancer was 0.29 (95% CI, 0.21-0.37; p < 0.001), that associated with pancreatic cancer was 0.19 (95% CI, 0.13-0.27; p < 0.001), that associated with advanced cancer stage (metastasis) was 0.69 (95% CI, 0.61-0.76; p < 0.001), and that associated with adenocarcinoma was 0.65 (95% CI, 0.56-0.72; p < 0.001). Median and 6-month overall survival (OS) were 1.3 months and 32.3%, respectively, with 6-month OS of 20.8% vs. 37.0% in lung vs. other cancers, respectively (p = 0.06) and 42.9% vs. 31.1% among those who underwent intervention vs. those who did not (p = 0.07). Cases discovered in recent years had better survival (HR = 0.98 (95% CI, 0.96-0.99; p = 0.003). While cancer-associated NBTE is a rare entity, lung cancers were the most common tumor site and are frequently associated with more advanced and metastatic cancer stages. The prognosis is dismal, especially among lung cancers.

5.
Sci Rep ; 13(1): 4997, 2023 Mar 27.
Article in English | MEDLINE | ID: mdl-36973326

ABSTRACT

Facile assembly, co-precipitation, and drop casting procedures have been used to construct SnO2/SrSnO3/Fe3O4/PVDF flexible nanocomposites. SnO2/SrSnO3/Fe3O4 nanocomposites (TSF NCs') have been successfully incorporated into polyvinylidene fluoride polymers (PF), according to the microstructural exploration of the systems, which was revealed by XRD, EDX, and ATR-FTIR analysis. The FESEM and cross-section areas demonstrated that the addition of TSF NCs' to PF porous material enhanced its surface characteristics and decreased its surface roughness. The optical gap was lowered from 3.90 to 3.07 eV, and it was discovered that both the refractive index and optical conductivity had improved when TSF NCs' were incorporated into PF. According to the observations, the supplement ratios have a profound influence on the dielectric properties of the nanocomposites. Moreover, the electrical parameters of TSF/PF nanocomposite are significantly modified. The TSF/PF magnetic nanocomposite has good magnetic reactivity and can be easily extracted from the aqueous solution using an external magnetic field, as demonstrated by VSM. This research has been conducted to obtain TSF/PF nanocomposites to be used in promising magno-optoelectronic applications.

7.
Ann Surg Oncol ; 30(7): 4030-4039, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36820939

ABSTRACT

BACKGROUND: Minimally invasive surgery is an expanding field of surgery that has replaced many open surgical techniques. Surgery remains a cornerstone in the treatment of esophageal cancer, yet it is still associated with significant morbidity and technical difficulties. Mediastinoscope-assisted esophagectomy is a promising technique that aims to decrease the surgical burden and enhance recovery. METHODS: PubMed, MEDLINE, and EMBASE databases were searched for publications on mediastinoscope-assisted esophagectomies for esophageal cancer. The primary endpoint was a postoperative anastomotic leak, while secondary endpoints were assessment of harvested lymph nodes (LNs), blood loss, chyle leak, hospital length of stay (LOS), operative (OR) time, pneumonia, wound infection, mortality, and microscopic positive margin (R1). The pooled event rate (PER) and pooled mean were calculated for binary and continuous outcomes respectively. RESULTS: Twenty-six out of the 2274 searched studies were included. The pooled event rate (PER) for anastomotic leak was 0.145 (0.1144; 0.1828). The PERs for chyle leak, recurrent laryngeal nerve injury/hoarseness, postoperative pneumonia, wound infection, early mortality, postoperative morbidity, and microscopically positive (R1) resection margins were 0.027, 0.185, 0.09, 0.083, 0.020, 0.378, and 0.037 respectively. The pooled means for blood loss, hospital stay, operative time, number of total harvested LNs, and number of harvested thoracic LNs were 159.209, 15.187, 311.116, 23.379, and 15.458 respectively. CONCLUSIONS: Mediastinoscopic esophagectomy is a promising minimally invasive technique, avoiding thoracotomy, patient repositioning, and lung manipulation; thus allowing for shorter surgery, decreased blood loss, and decreased postoperative morbidity. It can also be reliable in terms of oncological safety and LN dissection.


Subject(s)
Esophageal Neoplasms , Laparoscopy , Pneumonia , Humans , Esophagectomy , Mediastinoscopes , Anastomotic Leak/surgery , Esophageal Neoplasms/pathology , Length of Stay , Pneumonia/etiology , Minimally Invasive Surgical Procedures/methods , Postoperative Complications/surgery , Laparoscopy/methods , Treatment Outcome
8.
Phys Chem Chem Phys ; 25(5): 4236-4242, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36661277

ABSTRACT

Perovskite oxides are promising low-cost and stable alternative electrocatalysts for the oxygen reduction reaction (ORR), relative to the precious metal-based electrocatalysts. Despite the experimental research on substituting various transition metals into the B-site of perovskite catalysts to improve the ORR performance, the detailed ORR mechanism due to the substitution process is rarely studied. In this paper, the ORR activity of La0.5Sr0.5CoxFe1-xO3 perovskites (x = 0, 0.25, 0.5, 0.75, and 1) is studied by density functional theory (DFT). The ORR mechanism in alkaline solution is theoretically examined as a function of the Co/Fe composition at different potentials. The substitution of Co for Fe at the B-site of the perovskites dramatically changes the theoretical overpotential and enhances the activity. The HOO* formation is the potential-determining step for all the Co/Fe compositions. In comparison with the other compositions, the Co0.5/Fe0.5 composition exhibits the lowest overpotential and bonding with the reaction intermediates moderately. Furthermore, the oxygen binding energy is correlated with the bulk oxygen p-band center relative to the Fermi level. Among all the Co/Fe compositions, the Co0.5/Fe0.5 composition shows neither too low nor too high oxygen p-band center value. These results provide deep insights into the ORR mechanism on B-site substituted perovskites and guidelines for the design of cost-effective and Pt-free electrocatalysts for oxygen reduction.

9.
Eur Rev Med Pharmacol Sci ; 26(22): 8342-8350, 2022 11.
Article in English | MEDLINE | ID: mdl-36459044

ABSTRACT

OBJECTIVE: Besides repeated stress exposure, a sedentary lifestyle and low estrogen levels are risk factors for the development of functional dyspepsia (FD). The aim of this study was to find out the effect of adding aerobic exercise (5 sessions per week) to the daily application of a 40-minute Benson's relaxation therapy (BRT) (diaphragmatic breathing and progressive muscle relaxation applied for 20 minutes in the morning and evening) on Glasgow dyspepsia severity score (GDSS), cortisol, visual analogue scale (VAS) (for abdominal symptoms), estradiol (one of the endogenous estrogens), Pittsburgh sleep quality index (PSQI), and 42-item depression, anxiety, and stress scales (DASS-42) in 60 perimenopausal women with FD. PATIENTS AND METHODS: Women who consumed a daily dose of pantoprazole (40 mg tablet administered as a proton pump inhibitor drug) were randomly assigned to an 8-week study group (this group received aerobic exercise plus BRT, N=30) or an 8-week control group (this group received BRT only, N=30). RESULTS: Significant improvements were reported in all measured variables within women groups (except estradiol of the control group). Compared to the control group, the reported within-group significant improvements in GDSS, cortisol, VAS, PSQI, and DASS-42 were higher in the study group. CONCLUSIONS: Significant improvements in GDSS, cortisol, VAS, PSQI, and DASS-42 could be achieved after adding adjunctive therapies - aerobic exercise and BRT - to the medications of FD in perimenopausal women. Compared to BRT alone, physical exercise plus BRT significantly increases the levels of estradiol in perimenopausal women with FD.


Subject(s)
Dyspepsia , Humans , Female , Dyspepsia/therapy , Hydrocortisone , Relaxation Therapy , Perimenopause , Estrogens/therapeutic use , Exercise , Estradiol
10.
Int J Surg ; 104: 106739, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35764254

ABSTRACT

BACKGROUND: In the modern era, minimally invasive surgery is rapidly evolving and even replacing conventional open techniques in many surgical fields. Thyroidectomy was not an exception, with the introduction of multiple endoscopic thyroidectomy techniques. Trans-oral endoscopic trans-vestibular thyroidectomy (TOT) is a novel technique with promising outcomes. We conducted this meta-analysis to compare surgical outcomes and learning curves for TOT and other endoscopic thyroidectomy techniques. METHODS: A systematic review in PubMed, MEDLINE, and EMBASE databases was conducted searching for publications on TOT versus trans-axillary thyroidectomy (TAT). The primary endpoint was operative (OR) time. Secondary endpoints were number of harvested lymph nodes (LNs), estimated blood loss (EBL), recurrent laryngeal nerve (RLN) injury, hoarseness, seroma, infection, chyle leak, hypocalcemia, hospital length of stay (LOS), and Cost. We also investigated the learning curve for each technique. Leave-out-out analysis, meta-regression, and subgroup analysis were used. Random effect inverse variance method was utilized. RESULTS: Among 3820 retrieved studies, 15 studies (10 unmatched and 5 matched), with 2173 (TOT: 1024(47.12%) and TAT:1149(52.87%)) patients, met the inclusion criteria. The operative time and harvested L. Ns number were higher in TOT versus TAT (standard mean difference (SMD) = 0.72 [95%CI 0.07; 1.37], P = 0.029 and SMD = 0.32 [95%CI 0.02; 0.62], P = 0.036 respectively) while less EBL in TOT versus TAT (SMD = -0.26 [-0.43; -0.09], P = 0.0018). All other outcomes showed no significant difference between both groups. Weighted mean values for TOT and TAT were 158.03 vs 144.97 min for OR time, 6.33 vs 5.16 for harvested LNs, and $5,919.05 vs $6,253.79 for the cost. Statistical significance in learning curve development was noticed ranging between 6 and 15 annual cases. CONCLUSION: Trans-oral thyroidectomy is a safe and reliable technique with outcomes comparable to other endoscopic techniques. It provides better access to the central compartment with a more feasible LN dissection. Improvement in surgical outcomes is expected with growing learning curve and technique mastery.


Subject(s)
Learning Curve , Thyroid Neoplasms , Axilla , Endoscopy , Humans , Operative Time , Thyroidectomy
11.
Materials (Basel) ; 15(3)2022 Feb 06.
Article in English | MEDLINE | ID: mdl-35161168

ABSTRACT

The present study aimed to assess the radiological hazards associated with applying the investigated granite in the building materials and the infrastructures applications. The investigated granites are classified into four categories: El-Urf, barren, colourful and opaque. El Urf monzogranite intrudes metagabbro diorite complex with sharp contacts. Based on the activity concentrations, the environmental parameters such as absorbed dose rate (Dair), annual effective dose (AED), radium equivalent activity (Raeq), external (Hex) and internal (Hin) hazard indices were measured. The mineralized pegmatite is located in the southwestern foothill of the Gabal El Urf younger granite. It displays well-defined zonation of three zones: outer, middle and inner zones represented by potash feldspar, quartz and mica, respectively. The isorad map showed that El Urf monzogranite is barren (Up to 100 cps) surrounding an excavation of the studied pegmatite that exhibits moderate colorful mineralization (phase-I = 500-1500 cps) and anomalous opaque mineralization (phase-II = 1500-3500 cps) pegmatites. The obtained results of radionuclides activity concentrations illustrated that the Opaque granites have the highest values of 238U (561 ± 127 Bq kg-1), 232Th (4289 ± 891 Bq kg-1) and 40K (3002 ± 446 Bq kg-1) in the granites, which are higher than the recommended worldwide average. Many of the radiological hazard parameters were lesser than the international limits in the younger granites and barren pegmatites. All of these parameters were higher in the colorful and opaque mineralized pegmatites. The high activity and the elevated radiological hazard parameters in the mineralized pegmatites are revised to the presence of radioactive and radioelements bearing minerals, such as thorite, meta-autunite, kasolite, phurcalite, columbite, fergusonite, Xenotime and fluorapatite. Other instances of mineralization were also recorded as cassiterite, atacamite, galena, pyrite and iron oxide minerals. Thus, the granites with high radioactivity concentration cannot be applied in the different applications of building materials and ornamental stones.

12.
Malays J Pathol ; 43(2): 281-290, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34448792

ABSTRACT

INTRODUCTION: Serum protein electrophoresis (SPE) is a well-established laboratory technique. However, reporting of results varies considerably between laboratories. The variation in reporting can cause confusion to the clinician with a potential of adversely impacting patient care. The purpose of the survey was to find out the variation in reporting and to prepare recommendations to the Malaysian laboratories based on the survey to reduce both the variation in reporting between laboratories and the risk of misinterpretation of reports. MATERIALS AND METHODS: To determine the extent of variation in reporting of protein electrophoresis results questionnaires were distributed to the pathologists of various laboratories in Malaysia regarding the method, quantification of paraprotein concentrations and immunoglobulin assays, and information regarding current laboratory electrophoresis practices. RESULTS: Variation was found in the following reporting practices: (a) screening protocol; (b) reporting of serum albumin; (c) numerical reporting of protein fractions and paraprotein; (d) co-migration of a paraprotein with a normal serum protein; (e) reporting of multiple paraprotein bands (f) appearance of small abnormal band and oligoclonal bands and (g) communication about of interferences. CONCLUSION: The pathologists of the country made recommendations on the reporting of protein electrophoresis. Harmonised reporting will reduce inconsistency, variation in reporting, improve the quality of the report and most importantly improve patient care.


Subject(s)
Electrophoresis , Blood Proteins , Humans , Malaysia , Paraproteins , Surveys and Questionnaires
13.
Int J Biol Macromol ; 186: 278-288, 2021 Sep 01.
Article in English | MEDLINE | ID: mdl-34246674

ABSTRACT

The development of composite films with enhanced antibacterial and dye decolorization properties for water treatment has attracted a great attention. In this study, nickel oxide/chitosan/polyvinyl alcohol nanocomposite films containing different weight percentage of NiO nanoparticles with a dual functionality, removal of toxic dye and antibacterial properties, were prepared. Methyl orange (MO) was selected as a target pollutant. Additionally, the antimicrobial activity of the films against two Gram positive bacteria (Staphylococcus aureus and Bacillus cereus) and two Gram negative bacteria (Escherichia coli and Salmonella Typhimurium) was studied. The prepared samples were characterized by XRD, HRTEM, FESEM, ATR-FTIR, UV-Vis spectroscopy, and dielectric measurements. The morphological examination proved that the nanocomposite film has more porous structure compared to the unmodified chitosan/PVA. The antimicrobial tests indicated that the modified chitosan/PVA films have higher activity than pure chitosan/PVA toward all the tested pathogenic bacteria. The impact of the NiO amount (0.5, 1.5, 3, and 5 wt%), contact time (0-150 min), and adsorbent dose (40, 80, and 100 mg) on the removal of MO was studied. Dye adsorption results proved that the incorporation of 5 wt% NiO led to more than 2 fold increase in the dye removal percentage in comparison with the unmodified PVA/chitosan film.


Subject(s)
Anti-Bacterial Agents/pharmacology , Azo Compounds/isolation & purification , Bacteria/drug effects , Chitosan/pharmacology , Nanocomposites , Nickel/pharmacology , Polyvinyl Alcohol/pharmacology , Wastewater/chemistry , Water Pollutants, Chemical/isolation & purification , Water Purification , Adsorption , Anti-Bacterial Agents/chemistry , Bacteria/growth & development , Chitosan/chemistry , Disk Diffusion Antimicrobial Tests , Nickel/chemistry , Polyvinyl Alcohol/chemistry , Porosity , Surface Properties , Time Factors
14.
Nano Lett ; 21(12): 5247-5253, 2021 06 23.
Article in English | MEDLINE | ID: mdl-34100618

ABSTRACT

In heterogeneous catalysts, metal-oxide interactions occur spontaneously but often in an undesired way leading to the oxidation of metal nanoparticles. Manipulating such interactions to produce highly active surface of metal nanoparticles can warrant the optimal catalytic activity but has not been established to date. Here we report that a prior reduced TiO2 support can reverse the interaction with Pt nanoparticles and augment the metallic state of Pt, exhibiting a 3-fold increase in hydrogen production rate compared to that of conventional Pt/TiO2. Spatially resolved electron energy loss spectroscopy of the Ti valence state and the electron density distribution within Pt nanoparticles provide direct evidence supporting that the Pt/TiO2/H2O triple junctions are the most active catalytic sites for water reduction. Our reverse metal-oxide interaction scheme provides a breakthrough in the stagnated hydrogen production efficiency and can be applied to other heterogeneous catalyst systems composed of metal nanoparticles with reducible oxide supports.


Subject(s)
Metal Nanoparticles , Water , Catalysis , Oxides , Titanium
15.
J Parasit Dis ; 45(1): 228-235, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33746408

ABSTRACT

A total of 385 Red Sea coral reef fish representing three species; Broom tail wrasse (Cheilinus lunulatus), Blacktip grouper (Epinephelus fasciatus) and Rabbit fish (Siganus sp.). were examined for the presence of nematode Huffmanela species. The eggs of Huffmanela species were isolated and identified only from the C. lunulatus. The total prevalence of Huffmanela sp. infestation were 69.5%. The highest prevalence was observed in winter and the lowest in spring and summer. The prevalence was increased in correlation with fish body weight. Fully developed eggs of Huffmanela species were dark brown embryonated, elongated, with slightly protruding plugs. A high density of Huffmanela sp. eggs with different developmental stages packed the epithelial layer of the gas bladder. The surrounding tissue of gas bladder was hemorrhagic and sometimes necrotic associated with chronic inflammatory cell infiltration. This is the first record of Huffmanela species infestation in Broom tail wrasse C. lunulatus, Red Sea coral reef fishes.

16.
Nat Commun ; 12(1): 901, 2021 Feb 10.
Article in English | MEDLINE | ID: mdl-33568656

ABSTRACT

NOx abatement has been an indispensable part of environmental catalysis for decades. Selective catalytic reduction with ammonia using V2O5/TiO2 is an important technology for removing NOx emitted from industrial facilities. However, it has been a huge challenge for the catalyst to operate at low temperatures, because ammonium bisulfate (ABS) forms and causes deactivation by blocking the pores of the catalyst. Here, we report that physically mixed H-Y zeolite effectively protects vanadium active sites by trapping ABS in micropores. The mixed catalysts operate stably at a low temperature of 220 °C, which is below the dew point of ABS. The sulfur resistance of this system is fully maintained during repeated aging/regeneration cycles because the trapped ABS easily decomposes at 350 °C. Further investigations reveal that the pore structure and the amount of framework Al determined the trapping ability of various zeolites.

17.
ACS Appl Mater Interfaces ; 12(19): 21494-21504, 2020 May 13.
Article in English | MEDLINE | ID: mdl-32315147

ABSTRACT

Cation segregation, particularly Sr segregation, toward a perovskite surface has a significant effect on the performance degradation of a solid oxide cell (solid oxide electrolysis/fuel cell). Among the number of key reasons generating the instability of perovskite oxide, surface-accumulated positively charged defects (oxygen vacancy, Vo··) have been considered as the most crucial drivers in strongly attracting negatively charged defects (SrA - site') toward the surface. Herein, we demonstrate the effects of a heterointerface on the redistribution of both positively and negatively charged defects for a reduction of Vo·· at a perovskite surface. We took Sm0.5Sr0.5CoO3-δ (SSC) as a model perovskite film and coated Gd0.1Ce0.9O2-δ (GDC) additionally onto the SSC film to create a heterointerface (GDC/SSC), resulting in an ∼11-fold reduction in a degradation rate of ∼8% at 650 °C and ∼10-fold higher surface exchange (kq) than a bare SSC film after 150 h at 650 °C. Using X-ray photoelectron spectroscopy and electron energy loss spectroscopy, we revealed a decrease in positively charged defects of Vo·· and transferred electrons in an SSC film at the GDC/SSC heterointerface, resulting in a suppression of negatively charged Sr (SrSm') segregation. Finally, the energetic behavior, including the charge transfer phenomenon, O p-band center, and oxygen vacancy formation energy calculated using the density functional theory, verified the effects of the heterointerface on the redistribution of the charged defects, resulting in a remarkable impact on the stability of perovskite oxide at elevated temperatures.

18.
RSC Adv ; 10(70): 43092-43102, 2020 Nov 23.
Article in English | MEDLINE | ID: mdl-35514890

ABSTRACT

The characteristic properties of TiO2 (anatase) make doping necessary to enhance its photocatalytic activity. Herein, a density functional theory (DFT) study using the Heyd-Scuseria-Ernzerhof (HSE) hybrid functional was performed to precisely investigate the effect of mono- and co-doping (Ni, Se and B) on the structural, electronic and optical properties of anatase TiO2. Notably, the origin of the enhanced photocatalytic activity of the modified systems was determined. The response to visible light was enhanced for all the mono- and co-doped materials except for Bint, and the highest absorption coefficient was observed for Se4+ mono-doping and Se/Bint+sub and Ni/Bsub co-doping. The decrease in bandgap is associated with a red shift in the absorption edges with the smallest bandgap calculated for Ni/Bsub (2.49 eV). Additionally, the Ni, Se4+ and Se2- mono-doped systems and Ni/Se4+ co-doped systems are proposed as promising photocatalysts for water splitting applications and further experimental validation. Moreover, the Ni/Bint+sub and Se/Bint+sub co-doped materials can also be valuable photocatalysts for other energy applications due to their enhanced visible light activity and the prolonged lifetime of their produced charge carriers.

19.
Int J Biol Macromol ; 137: 1211-1220, 2019 Sep 15.
Article in English | MEDLINE | ID: mdl-31254576

ABSTRACT

The innovative nanocomposites (NCs) of antibacterial and antitumor 2-amino-5-S-benzyl-1, 3, 4-thiadiazole (ABMT): binary (NC1): ABMT-clay as well as the ternary (NC2): ABMT-clay-chitosan have been prepared following the top-down approach method. The ABMT molecules have been efficiently uploaded on the inorganic polymer potassium montmorlinite clay polymer (MMT). The NC is homogenously dispersed in the aqueous solutions without crystallization of ABMT. However, the dispersity of the small particle size and the crystallinity of NC1 is greatly enhanced in the presence of the biopolymer chitosan. The nanocomposites showed good non linear optical activity with suitable band gaps indicated the electron confinement in the NC. The loading and entrapment efficiency of ABMT onto MMT reached 89.3% in NC1 during 6 h of contact time with the aqueous solution of pH 6.8. The enhanced redox characteristics of NC1 relative to that of MMT suggested the better biological (antibacterial and antitumor) activity of NC1. Chitosan enhanced the redox and the optical properties of NC1 and its ability to undergo intercharge transfer to any acceptor sites. Hence, chitosan may added synergestic electron donation and, hence antitumor activity to the binary NC1.


Subject(s)
Chitosan/chemistry , Clay/chemistry , Nanocomposites/chemistry , Nanotechnology , Thiadiazoles/chemical synthesis , Thiadiazoles/pharmacology , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Chemistry Techniques, Synthetic , Thiadiazoles/chemistry
20.
Environ Toxicol Pharmacol ; 69: 44-50, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30953933

ABSTRACT

Industrial products contained nano-zinc oxide (ZnONP) can gain access to the aquaculture environment causing hazardous effects on the living biota. Therefore, this work was planned to examine the ameliorative effects of dietary supplementation of lycopene (LYC) and/or resveratrol (RES) against ZnONP toxicity in Nile tilapia. Five groups with 20 fish each were used; Control, received tap water only; ZnONP group, was intoxicated with ZnONP (50 mg/L); ZnONP-LYC group, was exposed to ZnONP and LYC (500 mg/ kg of the diet); ZnONP-RES group, was exposed to ZnONP and RES (50 mg/kg of the diet); ZnONP-LYC-RES group, was exposed to ZnONP and a combination of LYC and RES. The experiment was continued for 30 days. Fish blood and tissues were then assembled for determination of liver and kidney function and oxidative stress status in liver, kidney, and gills tissue. Results revealed a considerable elevation of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), cholesterol, urea, and creatinine with a noticeable lowering of total proteins and albumin serum levels in response to ZnONP intoxication. In addition, there were significant increase in malondialdehyde (MDA) and reduction in the reduced-glutathione (GSH) levels and superoxide dismutase (SOD) and catalase (CAT) activities. However, treatment with LYC and/or RES ameliorated the ZnONP-inflicted oxidative stress which possibly attributed to their beneficial antioxidant activities.


Subject(s)
Antioxidants/pharmacology , Dietary Supplements , Lycopene/pharmacology , Nanoparticles/toxicity , Resveratrol/pharmacology , Zinc Oxide/toxicity , Animals , Cichlids , Gills/drug effects , Gills/metabolism , Kidney/drug effects , Kidney/metabolism , Liver/drug effects , Liver/metabolism , Oxidative Stress/drug effects
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