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An increase in textile resistance to antimicrobial agents has posed a pressing need for the development of new antimicrobials. Therefore, the antimicrobial characteristics of thiophene and pyridine acetohydrazide derivatives have been developed as novel textile-modified complexes exhibiting antibacterial agents. Synthesis and characterization of pyridyl-thienyl acetohydrazide derivative (AHZ) using NMR (13C and 1H) and FTIR. Modification of cotton fabric (CF) with acetohydrazide (AHZ) and metal chlorides of divalent Cr, Mn, Co, Ni, Cu, and Zn and trivalent Fe, and Cr. SEM-EDX and Fourier-transform infrared were utilized to characterize cellulose-based cotton fabric (CF) attached to AHZ and their metal (M) complexes. Antimicrobial activity was examined against two types of bacteria, namely S. aureus and E. coli, and two types of fungi, namely C. albicans and A. flavus. All modified samples exhibited higher efficiency towards bacterial strains than fungal strains. In addition, cellulose modified with Ni (II) confers the most antibacterial protection efficiency.
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Understanding the deformation of energy storage electrodes at a local scale and its correlation to electrochemical performance is crucial for designing effective electrode architectures. In this work, the effect of electrolyte cation and electrode morphology on birnessite (δ-MnO2) deformation during charge storage in aqueous electrolytes was investigated using a mechanical cyclic voltammetry approach via operando atomic force microscopy (AFM) and molecular dynamics (MD) simulation. In both K2SO4 and Li2SO4 electrolytes, the δ-MnO2 host electrode underwent expansion during cation intercalation, but with different potential dependencies. When intercalating Li+, the δ-MnO2 electrode presents a nonlinear correlation between electrode deformation and electrode height, which is morphologically dependent. These results suggest that the stronger cation-birnessite interaction is the reason for higher local stress heterogeneity when cycling in Li2SO4 electrolyte, which might be the origin of the pronounced electrode degradation in this electrolyte.
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In this article, the synthesis, optical, and electrical properties of composites consisting of polyethylene oxide (PEO), carboxymethyl cellulose (CMC), and titanium dioxide nanoparticles are examined. Flexible nanocomposite samples comprising PEO, CMC, and TiO2 nanoparticles were produced swiftly via using the cast synthesis method. In addition, XRD and FT-IR analysis were performed in order to analyze the structures of the prepared samples. Our results demonstrate the PEO/CMC blend's effectiveness in interacting with TiO2 nanoparticles. The optical properties of the PEO/CMC and nanocomposite samples, such as the energy band gap, were studied using the UV/Vis optical absorbance. It was found that as TiO2 NP weight fraction increases, the energy gap narrows. Moreover, TiO2 nanoparticles with an average size of 16 nm were formed in spherical and rod shapes, according to a TEM image. The SEM images demonstrate how the distribution of TiO2 NPs increased upon the surfaces of the prepared films. The antibacterial activity in the nanocomposites was shown to be enhanced by the TiO2 NP concentrations. Finally, we proposed that PEO/CMC-0.8 wt. % TiO2 nanocomposites with enhanced optical, electrical, and dielectric properties should be used in electrochemical devices.
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Nanostructured birnessite exhibits high specific capacitance and nearly ideal capacitive behaviour in aqueous electrolytes, rendering it an important electrode material for low-cost, high-power energy storage devices. The mechanism of electrochemical capacitance in birnessite has been described as both Faradaic (involving redox) and non-Faradaic (involving only electrostatic interactions). To clarify the capacitive mechanism, we characterized birnessite's response to applied potential using ex situ X-ray diffraction, electrochemical quartz crystal microbalance, in situ Raman spectroscopy and operando atomic force microscope dilatometry to provide a holistic understanding of its structural, gravimetric and mechanical responses. These observations are supported by atomic-scale simulations using density functional theory for the cation-intercalated structure of birnessite, ReaxFF reactive force field-based molecular dynamics and ReaxFF-based grand canonical Monte Carlo simulations on the dynamics at the birnessite-water-electrolyte interface. We show that capacitive charge storage in birnessite is governed by interlayer cation intercalation. We conclude that the intercalation appears capacitive due to the presence of nanoconfined interlayer structural water, which mediates the interaction between the intercalated cation and the birnessite host and leads to minimal structural changes.
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Óxidos , Agua , Oxidación-Reducción , Óxidos/química , Agua/química , Difracción de Rayos XRESUMEN
Alkali ion insertion into Prussian blue from aqueous electrolytes is characterized with operando AFM and EQCM, showing coupling of current with deformation and mass change rates. Stable cycling occurs only with K+, attributed to its lower hydration energy. The (de)insertion of K+ results in reversible deformation even in the open framework structure.
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The hydro-alcoholic extract of Withania coagulans fruits was investigated for preliminary phytochemical screening and characterized by high-performance thin-layer chromatography. Column chromatography of the hydro-alcoholic extract of W. coagulans eluted with four different combinations of ethyl acetate and methanol yielded four fractions (WCF01, WCF02, WCF03, and WCF04). One of these fractions, WCF02, significantly (P < 0.05) inhibited in vitro α-amylase and α-glucosidase activity with IC50 values of 104.71 µg/mL and 70.79 µg/mL, respectively. WCF02 further reduced blood glucose levels in comparison to control in the starch tolerance test. The extract showed a relative dose-dependent effect. It was observed that none of the extracts could delay the peak blood glucose that was achieved after 60 min of carbohydrate challenge, but these blunted the glycemic peak.
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Background: Asthma is a chronic inflammatory disease characterized by reversible airway obstruction, hyperresponsiveness, and remodeling. Asthma prevalence has increased significantly globally over the last decade, and it remains incurable to this date. Aims and Objectives: The present study evaluated some of the antiasthmatic medicinal plants to assess their mode of action. Materials and Method: Animal models for milk-induced leukocytosis, milk-induced eosinophilia, mast cell degranulation, clonidine-induced catalepsy, and active paw anaphylaxis were used to assess the pharmacological effects of Ammi visnaga, Medicago sativa, and Urtica dioica. Results: Mice pretreated with diazepam, methanolic extract of M. sativa, and U. dioica exhibited significant (P < 0.05) inhibition in milk-induced leukocytosis. However, only M. sativa showed statistically significant (P < 0.05) results. All plants showed a statistically significant (P < 0.05) tendency to decrease milk-induced eosinophilia. Methanolic extracts of all plants significantly (P < 0.05) protected mast cells against degranulation by clonidine. A. visnaga and U. dioica significantly (P < 0.05) protected mice against clonidine-induced catalepsy. An acute treatment by M. sativa potentiated the catalepsy, while it significantly inhibited the catalepsy (P < 0.05) upon chronic treatment. In the allergic inflammation model, methanolic extracts of all plants under study decreased paw thickness in a statistically significant manner (P < 0.05). Conclusion: All the three plants in this study demonstrated anti-inflammatory and antihistaminic effects, as well as decreased paw thickness, validate anti-allergic properties. A. visnaga showed a mast cell-stabilizing effect. A. visnaga and U. dioica inhibited the histamine-mediated clonidine-induced catalepsy from mast cells which proves the antihistaminic activity of these plants.
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Objective: The purpose of this study was to evaluate the knowledge among dental students at King Khalid University, Jazan University, and Najran University in the kingdom of Saudi Arabia about when to repair or replace defective direct composite restoration. Materials and Methods: A questionnaire-based survey was formulated, pursuing the information about management (repair/replacement) of defective composite restorations and distributed among 200 dental students of three universities in the southern region of the kingdom of Saudi Arabia. The data were collected with the help of an online questionnaire. Data entry and the analysis were done using the statistical software package SPSS version 20.0. It was presented using descriptive statistics in the form of frequencies and percentages for qualitative variables, and range means and standard deviations for age, quantitative variable. Analytic statistics were done using Chi-Square tests (χ2) to test the significant difference between categorical variables. The level of significance, the p-value was 0.01(p<0.01). Results: The decision to choose between composite repair or replacement was influenced by whether this topic was taught to them at various undergraduate levels during Bachelor of Dental Surgery. The reason associated with the decision to repair defective composite restorations, 76% reported as cost-effective followed by Increased longevity (71%), the permanent filling (70%), patient's preference for repair (65%), and least time consuming (50%). 67% participants preferred significantly (p<0.001) repair due to secondary caries in the previously restored tooth with composite, followed by the small surface defect in a composite restoration (65%), risk of pulpal damage significantly (p<0.001) in a defective composite restoration (62.5%) and more invasive and destructive treatment option (35%). More than half of respondents 123 (61.5%) reported that they were not taught about composite repair during the Bachelor of Dental Surgery. Conclusion: It is suggested with the help of our study that didactic and clinical training components regarding composite repair should be seriously included in the teaching curriculum of dental institutions as it is in the best interest of the patient. Dental students should be provided with clinical training on this topic so that they can follow proper decision-making protocols available during repair or replacement of defective resin composite restorations. Other researches in the future can be carried out for refining the guidelines and techniques utilized for composite repair. (AU)
Objetivo: O objetivo deste estudo foi avaliar o conhecimento entre estudantes de odontologia da King Khalid University, Jazan University e Najran University, no reino da Arábia Saudita, sobre quando reparar ou substituir restaurações de resina composta direta defeituosas. Material e Métodos: Foi formulada uma pesquisa baseada em questionário, buscando informações sobre o manejo (reparo / substituição) de restaurações de resina composta e distribuída entre 200 estudantes de odontologia de três universidades da região sul do reino da Arábia Saudita. Os dados foram coletados com o auxílio de um questionário online. A entrada e análise dos dados foram feitas com o software estatístico SPSS versão 20.0. Foi apresentado por meio de estatística descritiva na forma de frequências e percentuais para as variáveis qualitativas, e amplitude de médias e desvios-padrão para a idade, variável quantitativa. A estatística analítica foi feita usando testes de qui-quadrado (χ2) para testar a diferença significativa entre as variáveis categóricas. Ao nível de significância, o valor de p foi de 0,01 (p <0,01). Resultados: A decisão de escolher entre o reparo ou substituição do compósito foi influenciada pelo fato de este tópico ter sido ensinado a eles em vários níveis de graduação durante o Bacharelado em Odontologia. O motivo associado à decisão de reparar restaurações de resina composta defeituosas, 76% relataram como custo-benefício seguido por maior longevidade (71%), restauração definitva (70%), preferência do paciente para reparo (65%) e menos demorado ( 50%). Sessenta e sete por cento dos participantes preferiram o reparo significativamente (p <0,001) devido a cárie secundária no dente previamente restaurado com resina composta, seguido pelo pequeno defeito de superfície em uma restauração composta (65%), risco de dano pulpar significativamente (p <0,001) em um restauração de resina composta com defeito (62,5%) e opção de tratamento mais invasiva e destrutiva (35%). Mais da metade dos entrevistados, 123 (61,5%) relataram que não foram ensinados sobre reparo de resina composta durante o Bacharelado em Odonotlogia. Conclusão: É sugerido com a ajuda de nosso estudo que os componentes do treinamento didático e clínico sobre reparo de resina composta devem ser seriamente incluídos no currículo de ensino de instituições odontológicas, pois é do interesse do paciente. Os estudantes de odontologia devem receber treinamento clínico sobre este tópico para que possam seguir os protocolos de tomada de decisão adequados disponíveis durante o reparo ou substituição de restaurações de resina composta com defeito. Outras pesquisas no futuro podem ser realizadas para refinar as diretrizes e técnicas utilizadas para reparo de resina (AU)
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Humanos , Resinas Compuestas , Caries Dental , PolimerizacionRESUMEN
The anion-deficient fluorite-related family of materials exhibits a number of commercially useful properties arising from the specific arrangement of anion vacancies in each structure. One recently reported member, Zn0.456In1.084Ge0.46O3, is the only known example with its particular complex structure in which cation coordinations span one 4-coordinate (4b), two 6-coordinate (8e and 16f), and one 8-coordinate (4a) site. A new, complete, solid solution (CuxZn1-x)0.456In1.084Ge0.46O3, (0 ≤ x ≤ 1) has been discovered via the isovalent substitution of Cu2+ for Zn2+, significantly expanding the known phase space of this structure. Synchrotron X-ray data confirm the ZIGO structure over the entire composition range. Inclusion of Cu in the structure is found to occur exclusively at the 16f site, increasing the number of cations mixed on that site from three to four, while all others remain singly occupied, including the other 6-coordinate (8e) position. Furthermore, transmission electron microscopy investigations show no evidence of long-range cation ordering. Thus, disorder on the 16f site appears remarkably favorable in this otherwise highly ordered structure. Nonideal trends in the lattice parameters and diffuse reflectance spectra as a function of Cu content are examined. Further implications of the mixed order and disorder in the solid solution for materials discovery and possible properties of interest are briefly discussed.
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Phytosterols are naturally occurring compounds in plants, structurally similar to cholesterol. The human diet is quite abundant in sitosterol and campesterol. Phytosterols are known to have various bioactive properties including reducing intestinal cholesterol absorption which alleviates blood LDL-cholesterol and cardiovascular problems. It is indicated that phytosterol rich diets may reduce cancer risk by 20%. Phytosterols may also affect host systems, enabling antitumor responses by improving immune response recognition of cancer, affecting the hormone dependent endocrine tumor growth, and by sterol biosynthesis modulation. Moreover, phytosterols have also exhibited properties that directly inhibit tumor growth, including reduced cell cycle progression, apoptosis induction, and tumor metastasis inhibition. The objective of this review is to summarize the current knowledge on occurrences, chemistry, pharmacokinetics and potential anticancer properties of phytosterols in vitro and in vivo. In conclusion, anticancer effects of phytosterols have strongly been suggested and support their dietary inclusion to prevent and treat cancers.
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Antineoplásicos Fitogénicos/farmacología , Neoplasias/tratamiento farmacológico , Neoplasias/prevención & control , Fitosteroles/farmacología , Animales , Antineoplásicos Fitogénicos/farmacocinética , Dieta , Humanos , Neoplasias/epidemiología , Fitosteroles/química , Fitosteroles/farmacocinéticaRESUMEN
Essential or volatile oils of plants have been variously reported to have many medicinal applications. Methanol, acetone and petroleum ether extracts of Ocimum basilicum and Glycyrrhiza glabra were screened for their repellency effect against Culex pipiens mosquito. The repellent action of the present plants extracts were varied depending on the solvent used and dose of extract. Methanol extract of O. basilicum exhibited the lowest repellent activity as it recorded 77.4% at 6.7mg/cm2. The petroleum ether and acetone extract of 0. basilicum showed repellency of 98.1 & 84.6% respectively, at dose of 6.7mg/cm2, while methanolic extract of G. glabra recorded 73.8 & 50.3% at dose of 6.7 &1.7mg/cm2 respectively, the petroleum ether and acetone extract of G. glabra showed repellency of 76.3 & 81.6%, respectively at dose of 6.7mg/cm2, compared with the commercial formulation, N.N. diethyl toulamide (DEET) which exhibited 100% repellent action at dose of 1.8mg/cm2, respectively. The results may contribute to design an alternative way to control mosquitoes currently based on applications of synthetic insecticides. These extracts could be developed commercially as an effective personal protection meaure against mosquito bites and thus to control diseases caused by mosquito-borne pathogens.
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Culex/efectos de los fármacos , Glycyrrhiza/química , Repelentes de Insectos/farmacología , Insecticidas/farmacología , Ocimum basilicum/química , Extractos Vegetales/farmacología , Acetona , Animales , Femenino , Repelentes de Insectos/química , Insecticidas/química , Metanol , Petróleo , Extractos Vegetales/químicaRESUMEN
Novel chitosan-ZnO composites have been synthesized as luminescent taggants for cellulosic materials. The synthesized chitosan-ZnO nanospheres (CS-ZnO NS), chitosan-ZnO-oleic acid quantum dots (CS-ZnO-oleic QD) and chitosan-ZnO-oleic acid:Eu(3+) doped nanorods (CS-ZnO-oleic:Eu(3+) NR) were characterized by X-ray diffraction, photoluminescence spectroscopy, FTIR spectroscopy and transmission electron microscopy. The prepared luminescent CS-ZnO composites were used in printing paste and applied to different types of papers and textiles by using screen printing technique. The colorimetric values of the printed CS-ZnO-oleic acid and CS-ZnO-oleic:Eu(3+) showed that printing caused slightly change in color values. Scanning electron microscopy images and color values of the printed surface showed that CS-ZnO-oleic QD and highly luminescence CS-ZnO-olic:Eu(3+) NR are suitable for use as a printed security feature.
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Celulosa/química , Quitosano/química , Nanocompuestos/química , Ácido Oléico/química , Coloración y Etiquetado/métodos , Óxido de Zinc/química , Luminiscencia , Mediciones Luminiscentes , Microscopía Electrónica de Transmisión , Nanocompuestos/ultraestructura , Nanotubos/química , Papel , Impresión , Puntos Cuánticos/química , Espectroscopía Infrarroja por Transformada de Fourier , Textiles , Difracción de Rayos XRESUMEN
Disappearing inks have been used in different fields, but it may be abused in forgery and counterfeiting. This research was conducted on the preparation of disappearing inks using different concentrations of thymolphthalein, phenolphthalein, and their mixture. The prepared inks were applied to different types of handwriting papers. It was found that the handwriting stability increased by increasing thymolphthalein, phenolphthalein, or alkali concentration, but in the case of using 4 mL of 1 normal (N) NaOH, the handwriting stability of phenolphthalein and its mixture inks decreased. Deciphering of the faded handwriting was evaluated by different methods; using optical deciphering, the faded handwriting did not respond to the different light sources. All the faded handwriting was visible when treated with alkaline solution. There was no change in the faded handwriting when heated to 100°C; phenolphthalein and mixture inks containing 0.5 mL of 1 N NaOH became red when only Azhar and Xerox papers were heated to 150°C.
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Paraoxonase is a high-density lipoprotein-associated enzyme and has been shown to reduce the susceptibility to low-density lipoprotein peroxidation. This study aimed to investigate the activity of serum paraoxonase in uremic patients on hemodialysis (HD) and in the predialysis period, and to evaluate the correlations of vascular disease with paraoxonase activity. Thirty patients with chronic renal failure (CRF) undergoing HD (group 1), 30 patients with CRF under conservative treatment (group 2), and 30 healthy controls (group 3) were included. Basal, salt-stimulated, and arylesterase activity were tested by UV spectrophotometry. Serum lipid parameters were determined. B-Mode Doppler ultrasound was used to assess common carotid intima-media thickness (IMT). Basal paraoxonase, salt-stimulated, and arylesterase activity showed no significant difference between group 1 and group 2. However, it was significantly lower in group 1 and in group 2 than controls. Carotid IMT was significantly higher in group 1 than group 2 and both were significantly higher than controls. Basal paraoxonase-1 (PON1), salt-stimulated PON1, and arylesterase activity correlate with BUN, but only basal PON1 and salt-stimulated PON1 correlate with serum albumin. Linear regression showed that the most significant determinant of carotid IMT was PON1 arylesterase activity in group 1 and arylesterase activity and basal PON1 activity in group 2. Patients with CRF, whether under HD or conservative treatment, have reduced basal and stimulated paraoxonase activities, and this could be an important factor causing increased vascular disease in those patients. Modifying this factor can be of great value to protect against this common complication.