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1.
Chemosphere ; 357: 141934, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38615957

RESUMO

In this study, the BiOBr/rGO nanocomposite photocatalysts are fabricated by a facile solvothermal method. The BiOBr growth on reduced graphene oxide (rGO) sheet could improve BiOBr's photocatalytic activity by increasing its adsorption ability, surface area, and charge carriers' separation efficiency. The prepared nanocomposites were characterized by XRD, Raman, FESEM, EDS, XPS, and UV-visible DRS. The BiOBr/rGO (BRG) nanocomposites showed improved photocatalytic activity for the photodegradation of Rhodamine B (RhB) dye and Tetracycline (TC) under visible light irradiation. Rhodamine B and tetracycline degradation efficiency were about 96% and 73% within 120 min under visible light irradiation. The PL analysis indicates that BiOBr/rGO nanocomposite exhibited maximum separation efficiency of photoinduced charge carriers. The trapping test confirmed that O2- and h+ are significant active photodegradation species. The GC-MS spectra detected the two plausible transformation routes of tetracycline degradation. The current work presented a low-cost and facile approach for fabricating Bi-based composites.


Assuntos
Antibacterianos , Bismuto , Grafite , Luz , Nanocompostos , Fotólise , Rodaminas , Tetraciclina , Grafite/química , Tetraciclina/química , Rodaminas/química , Bismuto/química , Catálise , Antibacterianos/química , Cinética , Nanocompostos/química , Poluentes Químicos da Água/química
2.
Med Sci Monit Basic Res ; 30: e943048, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38549239

RESUMO

BACKGROUND Cosmetics are applied topically to enhance appearance and are commonly used by women of all ages. Cosmetics contain many chemical agents, but the incidence of adverse reactions is low, possibly due to underreporting. This questionnaire-based study included 392 women to evaluate information on the types of cosmetics purchased between December 2018 and March 2019, their use by the women surveyed, and their associated adverse events. MATERIAL AND METHODS A cross-sectional study was conducted among 392 women in Abbottabad, Pakistan, using a pre-structured and validated questionnaire to evaluate information on the types of cosmetics, their use, and their associated adverse events. Part 1 of the study collected information about demographics. Part 2 contained a total of 11 items, and collected the frequency of use of cosmetic on skin and hair care products. Part 3 consisted of 4 items and collected information about problems encountered due to the use of cosmetics. RESULTS In the winter season, 47.7% (n=187) of women preferred chemical-based cosmetic products, while 30.9% (n=121) preferred Ayurvedic products. Among commonly used cosmetic products, 26.9% (n=106) of women used foundations. The most frequently used skin care product was face wash 39.5% (n=155). The most prevalent adverse events related to cosmetics were pimples (19.9%, n=78), redness (17.6%, n=69), and eye discomfort (15.8%, n=62). Furthermore, 51.3% (n=201) strongly agreed that cosmetics aid in getting a whiter complexion. CONCLUSIONS The survey concluded that most women preferred cosmetics with a chemical base, which are associated with rashes, redness, and acne. It is important to encourage cosmetovigilance and awareness campaigns among cosmetic product sellers and users.


Assuntos
Cosméticos , Humanos , Feminino , Paquistão/epidemiologia , Estudos Transversais , Cosméticos/efeitos adversos , Inquéritos e Questionários
3.
Plant Foods Hum Nutr ; 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38358638

RESUMO

Momordica charantia L. has been remained a well-known medicinal vegetable used traditionally. However, which part is most effective against which disorder, has been remained undiscovered yet. The objective of this study was to examine the antimicrobial, antihyperlipidemic and antihyperglycemic activities of peel, flesh, and seeds of bitter gourd, through in vitro and in vivo assays. Ethanolic extracts from powders of three fractions of bitter gourd were assessed for antimicrobial potential against bacterial and fungal strains, whereas, powders of these fractions were used to determine antihyperlipidemic and antihyperglycemic activity, in alloxan induced diabetic rats. Our results showed that BSE exhibited better antimicrobial activity against Bacillus cereus, whereas BFE exhibited better against Escherichia coli. Blood glucose was significantly lowered by all three powders in a dose dependent manner, when fed to diabetic rats, with the highest decrease by BSP, which reduced the glucose level from 296.20 ± 2.00 mg/dl to 123.10 ± 0.80 mg/dl, at 15 mg dose, after 28 days trial. Elevated levels of TC (101.18 ± 0.65 mg/dl), TG (83.69 ± 0.61 mg/dl) and LDL-C (25.90 ± 0.09 mg/dl) in positive control rats were lowered down in well manners by BSP at 15 mg dose, to 86.30 ± 0.53, 67.70 ± 0.53 and 19.32 ± 0.06 mg/dl, respectively. As compared to BFP and BPP, BSP showed significant involvement in antibacterial, antihyperglycemic, and antihyperlipidemic actions. Along with the edible flesh, peels and seeds, which are usually discarded as waste, could also be utilized for development of pharma foods capable of promoting health.

4.
An Acad Bras Cienc ; 95(3): e20221023, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38055498

RESUMO

In the current study, the solubility and permeability of Osthole-loaded microemulsion were enhanced, which increased bioavailability. In addition, Carbomer 940 was added for prolonged drug delivery. The microemulsion was prepared after the screening of Kukui oil, Labrasol (surfactant), and transcutol-P (co-surfactant). Pseudoternary phase diagrams were employed to find the microemulsion region. Box Behnken Design (BBD) was employed for optimizing microemulsions. Variables were related and compared using mathematical equations and response surface plots (RSP). MEBG was then compared with control gel on the basis of stability studies, drug permeation, skin irritation studies, and anti-inflammatory studies. Microemulsion preparations depicted a pH of 5.27 - 5.80, a conductivity of 139 - 185 µS/cm, a poly-dispersity index of 0.116 - 0.388, a refractive index of 1.330 - 1.427, an average droplet size of 64 - 89 nm, homogeneity, spherical shape, viscosity 52 - 185 cP. Predicted values of Optimized microemulsions showed more reasonable agreement than experimental values. The microemulsion was stable and non-irritating on Rabbit skin. MEBG showed a significant difference from control gel for percent edema inhibition from the standard. The permeation enhancing capability of MEBG using a suitable viscosity fabricates it promising carrier for transdermal delivery of Osthole.


Assuntos
Absorção Cutânea , Pele , Animais , Coelhos , Administração Cutânea , Tensoativos/metabolismo , Emulsões/metabolismo
5.
J Chem Phys ; 159(20)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38010333

RESUMO

Semiconductor-based photocatalysts have become increasingly used in the removal of pollutants from wastewater, especially antibiotics. A series of composite-based cuprous oxide and bismuth vanadate (Cu2O/BiVO4) composite-based photocatalysts were synthesized by using the chemical method. The structure of the Cu2O/BiVO4 composite was verified by using x-ray diffraction, scanning electron microscopy, photoluminescence, Fourier transform infrared spectroscopy, and UV-visible spectra. The degradation of methylene blue (MB) and tetracycline (TC) was investigated to check the photocatalytic activity of the Cu2O/BiVO4 composite series. The quantity of Cu2O was varied from 1% to 7% by weight to prepare the series of Cu2O/BiVO4 composites. The analysis of results verified that 5% Cu2O/BiVO4 exhibits an outstanding photocatalytic activity as compared to 1%, 3%, and 7% Cu2O/BiVO4, pure Cu2O, and pure BiVO4 under visible light irradiation. The optimum value of photocatalytic degradation achieved with 5% Cu2O/BiVO4 was 97% for MB dye and 95% for TC in 120 min, which is greater than the photocatalytic degradation of pure BiVO4 (MB 45% and TC 72%), pure Cu2O (MB 57% and TC 80%), 1% Cu2O/BiVO4 (MB 72% and TC 85%), 3% Cu2O/BiVO4 (MB 83% and TC 88%), and 7% Cu2O/BiVO4 (MB 87% and TC 91%). The stability and reusability of Cu2O/BiVO4 were also investigated. To check the major role of trapping in degradation, a trapping experiment was also performed by using three trapping agents: BQ, EDTA, and tBuOH. The results showed that Cu2O/BiVO4 exhibits an improved photocatalytic activity in the degradation of antibiotics in polluted water because the recombination rate of the electron-hole pair decreased and the surface area increased, which increased the active sites for redox reactions. Such a photocatalytic composite with high efficiency has various applications, such as energy production, environmental remediation, and water remediation.

6.
Environ Res ; 239(Pt 2): 117314, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37805186

RESUMO

Coastal ecosystems are facing heightened risks due to human-induced climate change, including rising water levels and intensified storm events. Accurate bathymetry data is crucial for assessing the impacts of these threats. Traditional data collection methods can be cost-prohibitive. This study investigates the feasibility of using freely accessible Landsat and Sentinel satellite imagery to estimate bathymetry and its correlation with hydrographic chart soundings in Port Klang, Malaysia. Through analysis of the blue and green spectral bands from the Landsat 8 and Sentinel 2 datasets, a bathymetry map of Port Klang's seabed is generated. The precision of this derived bathymetry is evaluated using statistical metrics like Root Mean Square Error (RMSE) and the coefficient of determination. The results reveal a strong statistical connection (R2 = 0.9411) and correlation (R2 = 0.7958) between bathymetry data derived from hydrographic chart soundings and satellite imagery. This research not only advances our understanding of employing Landsat imagery for bathymetry assessment but also underscores the significance of such assessments in the context of climate change's impact on coastal ecosystems. The primary goal of this research is to contribute to the comprehension of Landsat imagery's utility in bathymetry evaluation, with the potential to enhance safety protocols in seaport terminals and provide valuable insights for decision-making concerning the management of coastal ecosystems amidst climate-related challenges. The findings of this research have practical implications for a wide range of stakeholders involved in coastal management, environmental protection, climate adaptation and disaster preparedness.


Assuntos
Ecossistema , Imagens de Satélites , Humanos , Mudança Climática , Conservação dos Recursos Naturais , Água
7.
Environ Res ; 238(Pt 1): 117074, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37678506

RESUMO

Coastal ecosystems play an important part in mitigating the effects of climate change. Coastal ecosystems are becoming more susceptible to climate change impacts due to human activities and maritime accidents. The global shipping industry, especially in Southeast Asia, has witnessed numerous accidents, particularly involving passenger ferries, resulting in injuries and fatalities in recent years. In order to mitigate the impact of climate change on coastal ecosystems, this study aimed to evaluate the relationship between employees' perceptions of safety criteria and their own safety behaviour on Langkawi Island, Malaysia. A straightforward random sampling technique was employed to collect data from 112 ferry employees aboard Malaysian-registered passenger boats by administering questionnaires. The findings shed light on the strong connection between providing safety instructions for passengers and safety behaviour among ferry workers. Safety instructions should contain climate-related information to successfully address the effects of climate change. The instructions might include guidance on responding to extreme weather events and understanding the potential consequences of sea-level rise on coastal communities. The ferry company staff should also expand their safe behaviour concept to include training and preparation for climate-related incidents. The need to recognise the interconnectedness between climate change, ferry safety and the protection of coastal ecosystems is emphasised in this study. The findings can be utilised by policymakers, regulatory agencies and ferry operators to design holistic policies that improve safety behaviour, minimise maritime mishaps and preserve the long-term sustainability of coastal ecosystems in the face of difficulties posed by climate change.


Assuntos
Mudança Climática , Ecossistema , Humanos , Atividades Humanas , Inquéritos e Questionários
8.
Sci Rep ; 13(1): 12498, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37532701

RESUMO

Glass-ceramic nanocomposites (GCNs) of (10 - x) BaTiO3 (BT)-xPbTiO3 (PT)-60V2O5-30B2O3 with x = 0, 2.5, 5, 7.5 and 10 mol% were formed during heat treatment of conventional melt quenching glasses. X-ray diffraction was used to ensure glass and GCNs formation. Glasses and GCNs densities were measured by Archimedes principle. Fine polar clusters of lead titanate and/or barium titanate incorporation into vanadium borate glass matrix strongly depend on the composition. It was found out that the electrical conductivity of the initial glasses can be considerably improved by proper early stage of nanocrystallization at temperatures approaching the crystallization temperatures determined by DSC method. GCNs show massive increase in electrical conductivity (up to 6 orders of magnitude) as a function of BaTiO3 content. By increasing BaTiO3 content, the activation energy values have been found to increase. The enhancement in electrical conductivity of GCNs can be attributed to the increase in the crystalline phases in the glassy matrix which increases the concentrations of the V ion pairs.

9.
Phys Chem Chem Phys ; 25(32): 21736-21747, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37552204

RESUMO

A large power factor and ultralow lattice thermal conductivity in 2D-monolayers of AuX (X = Cu and Ag) are achieved via first principles calculations. Low phonon frequency, small Debye temperature and high Gruneisen parameter limit the intrinsic thermal conductivity of both the studied materials. An ultra-low lattice thermal conductivity of 0.13 (0.30) W m-1 K-1 and 0.66 (1.59) W m-1 K-1 is obtained for unstrained AuCu and AuAg monolayers, respectively, at 700 (300) K, which further reduces to 0.04 (0.09) and 0.26 (0.63) W m-1 K-1 at 6% biaxial tensile strain. Such values of thermal conductivity are lower than the critical thermal conductivity for the state-of-art thermoelectric materials (kl < 2 W m-1 K-1). The peak values of ZT for unstrained monolayers are 2.20 and 1.40, which enhances to 3.61 and 2.91 at 6% strain for AuCu and AuAg monolayers, respectively. Interestingly pudding-mold band textures are found to be responsible for this unusual thermoelectric behaviour. The stability concerns (chemical/dynamic/mechanical) of these monolayers are ensured to stimulate experimental determinations for novel synthesis and possible applications.

10.
Chemosphere ; 340: 139719, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37549746

RESUMO

Toxic and carcinogenic metal (loid)s, such arsenic (As) and cadmium (Cd), found in contaminated paddy soils pose a serious danger to environmental sustainability. Their geochemical activities are complex, making it difficult to manage their contamination. Rice grown in Cd and As-polluted soils ends up in people's bellies, where it can cause cancer, anemia, and the deadly itai sickness. Solving this issue calls for research into eco-friendly and cost-effective remediation technology to lower rice's As and Cd levels. This research delves deeply into the origins of As and Cd in paddy soils, as well as their mobility, bioavailability, and uptake mechanisms by rice plants. It also examines the current methods and reactors used to lower As and Cd contamination in rice. Iron-modified biochar (Fe-BC) is a promising technology for reducing As and Cd toxicity in rice, improving soil health, and boosting rice's nutritional value. Biochar's physiochemical characteristics are enhanced by the addition of iron, making it a potent adsorbent for As and Cd ions. In conclusion, Fe-BC's biomembrane properties make them an attractive option for remediating As- and Cd-contaminated paddy soils. More efficient mitigation measures, including the use of biomembrane technology, can be developed when sustainable agriculture practices are combined with these technologies.


Assuntos
Arsênio , Oryza , Poluentes do Solo , Humanos , Cádmio/análise , Ferro/química , Arsênio/análise , Solo/química , Oryza/química , Medição de Risco , Poluentes do Solo/análise
11.
Bioengineering (Basel) ; 10(7)2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37508825

RESUMO

The peel from Citrus-sinensis L. is a medicinally significant food waste, and its extract (O-Ext) could be significant against oxidative stresses and skin aging, However, the penetration barriers, instability in formulation, undefined toxicities, and enzymatic activities make the O-Ext difficult to formulate and commercialize. The goal of this study was to evaluate O-Ext against oxidative stress, prepare O-Ext-loaded nano-lipid carriers (O-NLCs), and load them into topical O/W-emulsion (O-NLC-E) to improve O-Ext permeation and its in vivo antiaging effects. TPC, TFC, DPPH activity, and mineral/metal contents of O-Ext were determined via atomic-absorption spectroscopy. For bioactive compounds profiling, GC-MS analysis was carried out. O-NLCs were prepared and tested for physicochemical attributes, while HaCaT and fibroblast cells were used to study permeation and cytotoxicity. The kinetic characteristics of ex vivo permeation through rat skin were established, following the Higuchi model. Following written consent, safety investigations were conducted on human volunteers for three months, where optimized O-NLC-E and B-NLC-E were regularly applied on cheeks. Non-invasive procedures were used to assess the volunteer's skin erythema, TEWL, sebum level, melanin, hydration, pH, elasticity, and pore sizes after specified intervals. The results demonstrated that applying O-NLC-E formulation to the skin of volunteers directed significant antiaging benefits. The study offers nanotechnology-based sustainability approach against skin ageing.

12.
Chemosphere ; 338: 139501, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37453525

RESUMO

The remediation of wastewater with microalgae is a new topic that concentrates on devising a cost-effective and environmentally beneficial method. Multiple microalgae and bacterial consortiums have recently been evaluated to determine if they can purify effluent from various sources. Critical to a system's efficacy is its ability to remove nutrients such as nitrogen (N) and phosphorus (P) and heavy metals such as arsenic (As), lead (Pb), and copper (Cu). This study compared traditional wastewater treatment systems to microalgae-based systems for treating different types of wastewater. The research investigates the potential for microalgae to cleanse wastewater. The research also evaluates wastewater parameters, methods, and scientific techniques for extracting nutrients and heavy metals from polluted water. According to the literature, Microalgae can remove between 98.7% and 100% of nitrogen (N), phosphorous (P), and heavy metals from various effluents. The paper concludes by discussing the difficulties of using microalgae to remediate wastewater. The elimination of nutrients from the effluent is influenced by biomass production, osmotic capacity, temperature, pH, and O2 concentration. Therefore, a "pilot" study is recommended to investigate contaminants.


Assuntos
Metais Pesados , Microalgas , Purificação da Água , Águas Residuárias , Nitrogênio , Purificação da Água/métodos , Fósforo , Biomassa
13.
J Phys Chem Lett ; 14(21): 5004-5012, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37222621

RESUMO

Recent advances in bandgap engineering have increased the possibility of vacancy ordered double halide perovskites (VO-DHPs), Cs2SnX6 where X = Cl, Br, I with designable optoelectronic features. Doping with La3+ ions modulates the band gap from 3.8 to 2.7 eV, allowing a steady room temperature dual emission (PL) centered at 440 and 705 nm in Cs2SnCl6. Pristine Cs2SnCl6 and La:Cs2SnCl6 both have a crystalline cubic structure with a space symmetry of Fm3m. The cubic phase correlates well with the Rietveld refinement. SEM analysis confirms anisotropic development with huge micrometer-sized (>10 µm) truncated octahedral structures. DFT investigations show that the insertion of La3+ ions into the crystal lattice leads to the band splitting. The present study elaborates the experimental understanding of the dual PL emission properties of La:Cs2SnCl6 leaving a scope for detailed theoretical study on the origin of the complex electronic transitions involving f-orbital electrons.

14.
Int J Biol Macromol ; 236: 123988, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36907299

RESUMO

This study aimed to develop a robust approach for the early diagnosis and treatment of tumors. Short circular DNA nanotechnology synthesized a stiff and compact DNA nanotubes (DNA-NTs) framework. TW-37, a small molecular drug, was loaded into DNA-NTs for BH3-mimetic therapy to elevate the intracellular cytochrome-c levels in 2D/3D hypopharyngeal tumor (FaDu) cell clusters. After anti-EGFR functionalization, the DNA-NTs were tethered with a cytochrome-c binding aptamer, which can be applied to evaluate the elevated intracellular cytochrome-c levels via in situ hybridization (FISH) analysis and fluorescence resonance energy transfer (FRET). The results showed that DNA-NTs were enriched within the tumor cells via anti-EGFR targeting with a pH-responsive controlled release of TW-37. In this way, it initiated the triple inhibition of "BH3, Bcl-2, Bcl-xL, and Mcl-1". The triple inhibition of these proteins caused Bax/Bak oligomerization, leading to the perforation of the mitochondrial membrane. This led to the elevation of intracellular cytochrome-c levels, which reacted with the cytochrome-c binding aptamer to produce FRET signals. In this way, we successfully targeted 2D/3D clusters of FaDu tumor cells and achieved the tumor-specific and pH-triggered release of TW-37, causing tumor cell apoptosis. This pilot study suggests that anti-EGFR functionalized, TW-37 loaded, and cytochrome-c binding aptamer tethered DNA-NTs might be the hallmark for early tumor diagnosis and therapy.


Assuntos
Neoplasias Hipofaríngeas , Nanotubos , Humanos , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Neoplasias Hipofaríngeas/tratamento farmacológico , Medicina de Precisão , Projetos Piloto , Citocromos c/metabolismo , DNA
15.
Environ Sci Pollut Res Int ; 30(14): 41405-41418, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36633742

RESUMO

4-Nitrophenol (4-NP) is reported to originate disadvantageous effects on the human body collected from industrial pollutants; therefore, the detoxification of 4-NP in aqueous contamination is strongly recommended. In this study, the heterojunction mesoporous α-Fe2O3/TiO2 modulated with diverse Ag percentages has been constructed via a sol-gel route in the occurrence of a soft template P123. The formation of biphasic crystalline TiO2 anatase and brookite phases has been successfully achieved with the average 10 nm particle sizes. The photo/-catalytic reduction of 4-NP has been performed utilizing NaBH4 as a reducing agent with and without visible illumination. All Ag/Fe2O3/TiO2 nanocomposites exhibited significantly higher photo/-catalytic reduction efficiency than pure Fe2O3, TiO2 NPs, and Fe2O3/TiO2 nanocomposite. 2.5% Ag/Fe2O3/TiO2 nanocomposite was considered the highest and superior photocatalytic reduction efficiency, and it almost achieved 98% after 9 min. Interestingly, the photocatalytic reduction of 4-NP was accelerated 9 times higher than the catalytic reduction over 2.5% Ag/Fe2O3/TiO2; its rate constant value was 709 and 706 times larger than pure TiO2 and Fe2O3 NPs, respectively. The enhanced photocatalytic reduction ability of Ag/Fe2O3/TiO2 nanocomposite might be referred to as significantly providing visible light absorption and a large surface area, and it can upgrade the effective separation and mobility of electron holes. The stability of the synthesized catalysts exhibited that the obtained catalysts can undergo a slight decrease in reduction efficiency after five successive cycles. This approach highlights a novel route for constructing ternary nanocomposite systems with high photo/-catalytic ability.


Assuntos
Luz , Prata , Humanos , Prata/química , Titânio/química
16.
J Colloid Interface Sci ; 631(Pt B): 164-172, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36401924

RESUMO

Photocatalytic CO2 reduction and H2 production are a competitive reaction, and existing active sites cannot take into account the simultaneous gas-solid and liquid-solid reaction processes. Hence, a metallic aerogel (CuAg2.5) with dual active sites was constructed via straightforward in-situ reduction process. CuAg2.5 aerosol has larger porosity and CO2 adsorption capacity, which enables H2O and CO2 to fully contact it. The CuAg2.5 can also construct the cooperative dual active sites, which can conduct CO2 reduction reaction on Ag surface and proton reduction reaction on Cu surface, respectively, thereby efficiently guiding the rapid migration of photogenerated carriers. The yields of CO (18533 µmol g-1) and H2 (20340 µmol g-1) for CuAg2.5 are much higher than those of single metals. The ratio of CO and H2 can also regulated via changing the ratio of Ag and Cu. This work gives new insights into the fabrication of unique high-efficiency plasmonic photocatalysts.

17.
Molecules ; 27(19)2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36235103

RESUMO

We hereby discuss the thermoelectric properties of PdXSn(X = Zr, Hf) half Heuslers in relation to lattice thermal conductivity probed under effective mass (hole/electrons) calculations and deformation potential theory. In addition, we report the structural, electronic, mechanical, and lattice dynamics of these materials as well. Both alloys are indirect band gap semiconductors with a gap of 0.91 eV and 0.82 eV for PdZrSn and PdHfSn, respectively. Both half Heusler materials are mechanically and dynamically stable. The effective mass of electrons/holes is (0.13/1.23) for Zr-type and (0.12/1.12) for Hf-kind alloys, which is inversely proportional to the relaxation time and directly decides the electrical/thermal conductivity of these materials. At 300K, the magnitude of lattice thermal conductivity observed for PdZrSn is 15.16 W/mK and 9.53 W/mK for PdHfSn. The highest observed ZT value for PdZrSn and PdHfSn is 0.32 and 0.4, respectively.

18.
Biomedicines ; 10(9)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36140367

RESUMO

Although Mangifera indica L. extract (M-Ext) of the peel and kernel possesses potent antioxidant and excellent antiaging qualities, the effects are only partially seen because of the skin's limited ability to absorb it. M-Ext was loaded into nanolipid carriers (M-NLCs) in this work to create a green topical formulation that would boost antiaging efficacy and address penetration deficit. Compound identification was done using GCMS and atomic absorption spectroscopy for heavy metals in M-Ext. M-Ext was also evaluated against oxidative stress antioxidant enzymes. The M-NLCs were fabricated and evaluated for their physicochemical characterizations. Cytotoxicity and cell permeation analysis of M-Ext and M-NLCs were carried out in fibroblasts and HaCaT cell lines. An ex vivo permeation study of M-Ext and M-NLC-loaded emulsion was performed through rat skin and the kinetic parameters were determined. Kinetic data showed that the ex vivo permeation of M-NLC-loaded emulsion through rat skin followed the Higuchi model. The safety profile was evaluated in human volunteers after written consent. Three months' in vivo investigations were conducted using the optimized M-NLC-loaded emulsion and vehicle (B-NLC-loaded emulsion) on human cheeks for comparison. The volunteers' skin erythema level, melanin contents, TEWL index, moisture contents, sebum level, elasticity, pH, and pore size were examined after the first, second, and third month via noninvasive techniques. There were significant findings for physicochemical characterizations and in vitro and ex vivo studies. The findings demonstrate that the green nanolipid carriers amplified the overall antioxidant effectiveness and may represent an emerging treatment strategy for oxidative stresses and aging.

19.
Org Biomol Chem ; 20(39): 7814-7820, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36165391

RESUMO

Catalytic oxidation using manganese corrole is a hot topic of contemporary porphyrin chemistry, in which PhIO, TBHP, PhI(OAc)2, KHSO5 and m-CPBA are usually used as oxidants. This article reports the first selective oxidation of styrene to benzaldehyde using a manganese(III) corrole catalyst and sodium nitrite (NaNO2) as oxidant and cocatalyst at room temperature. The yield was 158.1% in air and 96.5% under a nitrogen atmosphere, showing oxygen might be involved in the reaction and that NaNO2 is an oxygen source and cocatalyst in the system. The peripheral electron-withdrawing substituents of the manganese corrole were favorable to the catalytic reaction. Radical inhibition and H218O experiments proved that the catalytic reaction was a free radical and hydrolysis-involved reaction.


Assuntos
Metaloporfirinas , Porfirinas , Benzaldeídos , Catálise , Manganês , Nitrogênio , Oxidantes , Oxirredução , Oxigênio , Nitrito de Sódio , Estireno
20.
Int J Food Sci ; 2022: 4804408, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35959224

RESUMO

Pumpkin is a well-known vegetable, among the members of Cucurbitaceae family, due to its importance as pharma food. Keeping in view the antidiabetic and plasma lipids lowering potential of pumpkin, the present study was conducted to investigate that, which part of pumpkin (peel, flesh, and seeds), possess more bioactive compounds, exhibiting antihyperglycemic and antihyperlipidemic potential. Albino rats with 190-210 g body weight were divided into 11 groups. Five rats were included in each group; group A was negative control, group B was positive control, and groups C to K were diabetic rats fed with pumpkin peel, flesh, and seed powders. Diabetes was induced in rats with the help of alloxan monohydrate. During 28 days of experimental period, blood glucose level of different rat's groups was checked with the help of glucometer, at every 7 days interval and at the end of 28 days study, plasma lipids were checked with the help of commercial kits. A significant decrease in blood glucose level (128.33 ± 1.67 mg/dl), TC (88.43 ± 0.66 mg/dl), TG (69.79 ± 0.49 mg/dl), and LDL-C (21.45 ± 0.08 mg/dl) was recorded in rat groups fed with 15 g pumpkin seed powder, at the end of study. After pumpkin seeds, second significant antihyperglycemic and antihyperlipidemic effect was recorded in rat's groups fed with 15 g pumpkin peel powder. Pumpkin flesh powder effect in lowering blood glucose level and plasma lipids was less significant as compared to seeds and peel powder. As the dose of the pumpkin powders was increased from 5 to 10 and then 15 g, the blood glucose-lowering and plasma lipid-lowering effect became more significant. Similarly, as the experimental duration was expanded from first week to 28 days, this antihyperglycemic and antihyperlipidemic effect became more significant. These results were sufficient to conclude that pumpkin has high potential to be used in human diet to cope with noncommunicable diseases like diabetes and hypercholesterolemia.

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