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1.
Plant Foods Hum Nutr ; 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38969792

RESUMEN

Avocado fruit is a rich source of phytonutrients such as vitamins, minerals, carotenoids, carbohydrates, polyphenols and unsaturated fatty acids. However, due to its climacteric nature, fruits are highly susceptible to storage temperature, resulting in poor shelf life and reduced quality. In the present study avocado fruits (Accession CHES-HA-I/I) were stored at different low temperatures (5, 9 and 12 °C with 90-95% relative humidity, RH) to identify optimum low temperature for cold storage. In a further experiment, avocado fruits were treated with 1-methylcyclopropene (1-MCP, 500 ppb) and chitosan (0.5%) to extend the shelf life with better fruit quality. The results showed that storage temperatures had significant effect on physiological, biochemical and antioxidant activities of fruits. Lower physiological loss in weight (PLW), reduced respiration and ethylene production, and higher carbohydrates, protein and fat content were recorded in fruits stored at 9 °C as compared to 12 °C. Similarly, maximum antioxidant properties in terms of free radical scavenging activity (FRSA) and ferric reducing ability of plasma (FRAP) was found in avocado fruits stored at 9 °C. It was also noticed that chilling injury was developed in fruits stored under 5 °C. In addition, exogenous application of 1-MCP significantly reduced respiration and ethylene production rate at 9 °C and extended the shelf life up to 42 days with better fruit quality and more antioxidant activities. However, chitosan treated and control fruits had shelf life up to 28 and 21 days respectively, with minimum nutritional content. From this study it is concluded that a storage temperature of 9 °C and 1-MCP treatment significantly enhanced the shelf life of avocado fruits with better fruit quality as compared to other storage temperatures (5 and 12 °C) and postharvest treatment (chitosan).

2.
Sci Rep ; 12(1): 753, 2022 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-35031647

RESUMEN

Raman scattering and ab initio Raman/phonon calculations, supported by X-ray diffraction, are combined to study the vibrational properties of Zn1-xBexTe under pressure. The dependence of the Be-Te (distinct) and Zn-Te (compact) Raman doublets that distinguish between Be- and Zn-like environments is examined within the percolation model with special attention to x ~ (0,1). The Be-like environment hardens faster than the Zn-like one under pressure, resulting in the two sub-modes per doublet getting closer and mechanically coupled. When a bond is so dominant that it forms a matrix-like continuum, its two submodes freely couple on crossing at the resonance, with an effective transfer of oscillator strength. Post resonance the two submodes stabilize into an inverted doublet shifted in block under pressure. When a bond achieves lower content and merely self-connects via (finite/infinite) treelike chains, the coupling is undermined by overdamping of the in-chain stretching until a «phonon exceptional point¼ is reached at the resonance. Only the out-of-chain vibrations «survive¼ the resonance, the in-chain ones are «killed¼. This picture is not bond-related, and hence presumably generic to mixed crystals of the closing-type under pressure (dominant over the opening-type), indicating a key role of the mesostructure in the pressure dependence of phonons in mixed crystals.

3.
J Food Sci Technol ; 58(8): 3039-3048, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34294966

RESUMEN

Capsicums lose water very rapidly after harvest and the moisture loss causes severe shriveling making them unmarketable within 2-3 days. The moisture loss occurs even under low temperature conditions, though at lesser rates. Bell peppers packed in corrugated fiber board boxes (CFB) tend to lose moisture continuously as these boxes are permeable to both water vapour and respiratory gases even if they are non-ventilated. To reduce the moisture loss and maintain freshness, yellow colour capsicum (cv. Bachata) were packed in CFB boxes and over wrapped with different semi-permeable films using shrink wrapping technology. This box shrink wrapping significantly lowered the weight loss and maintained firmness of capsicum at ambient (25.7-33.2 °C and 25-63% RH) and low temperature (8 °C ± 0.5 and 80 ± 5% RH) conditions. Yellow colour capsicums packed in this way could be stored for 11 days at ambient temperature with a weight loss of < 6% as compared to about 20% weight loss in non-wrapped fruits. The storage life could be extended to 5 weeks by storing these shrink wrapped boxes at 8 °C without any shriveling and with a weight loss of < 5%. In addition to maintaining high humidity, the lower O2 and higher CO2 levels maintained surrounding the produce in the wrapped boxes helped to avoid shriveling and to retain the quality in terms of surface colour, firmness and other quality traits. The absorption of excessive relative humidity by CFB itself in the over wrapped boxes helped in avoiding condensation of water droplets. This in turn avoided the development of fungal growth and thus the risk of fruit decay.

4.
Pain Ther ; 10(2): 895-908, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34244979

RESUMEN

Painful diabetic neuropathy is a common disease that results in significant pain and disability. Treatment options have traditionally consisted of conservative measures including topical and oral medication management as well as transcutaneous electrical stimulation units. These treatments demonstrate various degrees of efficacy, and many times initial treatments are discontinued, indicating low levels of satisfaction or poor tolerability. Spinal cord stimulation has been proposed as an alternative therapy for treatment of painful diabetic neuropathy of the lower extremities. We performed a systematic literature review to evaluate the safety and effectiveness of this procedure. A literature search identified 14 prospective studies. Based on our analysis of the available evidence, there is moderate-quality evidence for the safety and efficacy of spinal cord stimulation for painful diabetic neuropathy. However, further high-quality research, including a large-scale randomized controlled trial is warranted.

5.
Sci Rep ; 10(1): 19803, 2020 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-33188245

RESUMEN

The generic 1-bond → 2-mode "percolation-type" Raman signal inherent to the short bond of common A1-xBxC semiconductor mixed crystals with zincblende (cubic) structure is exploited as a sensitive "mesoscope" to explore how various ZnSe-based systems engage their pressure-induced structural transition (to rock-salt) at the sub-macroscopic scale-with a focus on Zn1-xCdxSe. The Raman doublet, that distinguishes between the AC- and BC-like environments of the short bond, is reactive to pressure: either it closes (Zn1-xBexSe, ZnSe1-xSx) or it opens (Zn1-xCdxSe), depending on the hardening rates of the two environments under pressure. A partition of II-VI and III-V mixed crystals is accordingly outlined. Of special interest is the "closure" case, in which the system resonantly stabilizes ante transition at its "exceptional point" corresponding to a virtual decoupling, by overdamping, of the two oscillators forming the Raman doublet. At this limit, the chain-connected bonds of the short species (taken as the minor one) freeze along the chain into a rigid backbone. This reveals a capacity behind alloying to reduce the thermal conductivity as well as the thermalization rate of photo-generated electrons.

6.
Int J Clin Pediatr Dent ; 11(2): 105-109, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29991862

RESUMEN

AIM: The aim of the study was to test the antibacterial activity of manuka honey and compare its efficacy with another commercially available honey (Dabur honey) on the cariogenic bacteria on Streptococcus mutans and Lactobacillus. MATERIALS AND METHODS: An in vitro study was carried out on 40 agar specimens; the samples were divided into two groups of 20 samples consisting of S. mutans and Lactobacil-lus respectively. The 20 samples in each group were further subdivided into four groups of five each, which were tested with 25% manuka honey, 100% manuka honey, 25% Dabur honey, and 100% Dabur honey for both Lactobacillus and S. mutans groups. The antibacterial activity was tested using the agar well diffusion method against S. mutans and Lacto-bacillus. Antibacterial activity was assessed by measuring the diameter of inhibition of zones surrounding the wells. The results obtained were statistically analyzed (one-way analysis of variance test, p-value). RESULTS: The results showed that 25% of manuka honey has statistically significant (p ≤ 0.001) antibacterial effect than 25% of Dabur honey on both Streptococcus and Lactobacillus species, and manuka honey with 100% concentration showed a statistically significant (p ≤ 0.001) antibacterial effect than 100% Dabur honey on the same species of bacteria. 100% of both the honeys showed statistically significant (p ≤ 0.001) antibacterial effect than 25% concentrations of the same on S. mutans and Lactobacillus. CONCLUSION: Manuka honey had more antibacterial activity than Dabur honey on S. mutans and Lactobacillus bacteria in the in vitro study. This effect was dependent on the concentration of honey used.How to cite this article: Beena JP, Sahoo P, Konde S, Raj SN, Kumar NC, Agarwal M. Manuka Honey: A Potent Cariostatic Agent-An in vitro Study. Int J Clin Pediatr Dent 2018;11(2):105-109.

7.
Mar Pollut Bull ; 119(2): 223-230, 2017 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-28454763

RESUMEN

The present study evaluated the origin and distribution of polycyclic aromatic hydrocarbons (PAHs) and the organic matter (OM) in the surface sediment of the São Paulo River estuary, Todos os Santos Bay (TSB), Brazil. The samples were collected in the rainy (CP1) and the dry (CP2) seasons. We analyzed the 16 PAHs from the United States Environmental Protection Agency (US EPA) priority pollutant list, total organic carbon (TOC), total nitrogen (N), and stable carbon isotope (δ13C). The total concentration of PAHs ranged from 11.45±1.28 to 1825.35±107.96ngg-1, while TOC ranged from 3.8 to 27.7gkg-1. CP1 showed the highest concentrations for all parameters. The δ13C ratio indicated terrigenous OM (-23.81 to -26.63‰). The TOC/N ratio (C/N) indicated transitional OM (12.32 to 24.39), in addition to the continental origin. The diagnostic ratios of PAHs origin revealed only pyrolytic source, although close to areas with a history of petroleum contamination.


Asunto(s)
Sedimentos Geológicos/química , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes Químicos del Agua/análisis , Bahías , Brasil , Monitoreo del Ambiente , Estuarios , Petróleo , Contaminación por Petróleo
8.
J Phys Condens Matter ; 28(1): 015602, 2016 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-26656791

RESUMEN

We report the high-pressure vibrational properties and a pressure-induced electronic topological transition in the wide bandgap semiconductor Sb2S3 (E g = 1.7-1.8 eV) using Raman spectroscopy, resistivity and x-ray diffraction (XRD) studies. In this report, high-pressure Raman spectroscopy and resistivity studies of Sb2S3 have been carried out to 22 GPa and 11 GPa, respectively. We observed the softening of phonon modes [Formula: see text], [Formula: see text] and B 2g and a sharp anomaly in their line widths at 4 GPa. The resistivity studies corroborate this anomaly around similar pressures. The changes in resistivity as well as Raman line widths can be ascribed to the strong phonon-phonon coupling, indicating clear evidence of isostructural electronic topological transition in Sb2S3. The previously reported pressure dependence of a/c ratio plot obtained also showed a minimum at ~5 GPa consistent with our high-pressure Raman and resistivity results.

9.
Chem Sci ; 7(7): 4613-4623, 2016 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-30155109

RESUMEN

Biomimetic antibacterial polymers, the functional mimics of antimicrobial peptides (AMPs), targeting the bacterial cell membrane have been developed to combat the problem of antibiotic resistance. Amphiphilicity, a balance of cationic charge and hydrophobicity, in these polymers has been shown to be pivotal for their selective interactions with anionic lipid membranes of bacteria instead of zwitterionic mammalian (human erythrocyte) membranes. However, it is unclear if and to what extent hydrogen bonding in amphiphilic antibacterial polymers contributes to this membrane binding specificity. To address this, we employ isosteric substitution of ester with amide moieties that differ in their potency for hydrogen bonding in the side chains of N-alkyl maleimide based amphiphilic polymers. Our studies reveal that amide polymer (AC3P) is a potent antibacterial agent with high membrane-disrupting properties compared to its ester counterpart (EC3P). To understand these differences we performed bio-physical experiments and molecular dynamics (MD) simulations which showed strong interactions of AC3P including hydrogen bonding with lipid head groups of bacterial model lipid bilayers, that are absent in EC3P, make them selective for bacterial membranes. Mechanistic investigations of these polymers in bacteria revealed specific membrane disruptive activity leading to the delocalization of cell division related proteins. This unprecedented and unique concept provides an understanding of bacterial membrane interactions highlighting the role of hydrogen bonding. Thus, these findings will have significant implications in efficient design of potent membrane-active agents.

10.
Nanotechnology ; 25(49): 495704, 2014 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-25412640

RESUMEN

The modification of individual oxygen functional groups and the resultant optical properties of a graphene oxide suspension were investigated using a controlled photothermal reduction by infrared irradiation. The evolution of the structural and optical characteristics of GO suspensions was obtained from Raman spectra, x-ray photoelectron spectroscopy, optical absorption, and steady state and time-resolved photoluminescence spectroscopy. The results suggest the gradual restoration of sp(2) clusters within the sp(3) matrix with an increase of the reduction time and power density. The yellow-red emission (∼610 nm) originated from the defect-assisted localized states in GO due to epoxy/hydroxyl (C-O/-OH) functional groups and that of the blue emission (∼500 nm) was ascribed to the carbonyl (C=O)-assisted localized electronic states. With an increase in the reduction time and IR power density, the intensity of the yellow-red emission was found to decrease, with the blue emission being prominent. These experimental findings open up a new dimension for controlling the optical absorption and emission properties of graphene oxide by tailoring the oxygen functional groups, which may lead to the potential application of graphene-based optoelectronic devices.

11.
Pain Physician ; 15(1): 65-74, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22270739

RESUMEN

BACKGROUND: Intrathecal delivery of baclofen (ITB) is effective at controlling spasticity. However, it requires the placement of a catheter into the intrathecal space, and a pump with a reservoir for the medication. The process of placing the catheter and pump are prone to complications. OBJECTIVES: The objective of this paper is to determine factors contributing to rising complication rates after intrathecal catheter/pump placement in a national sample of pediatric patients. STUDY DESIGN: This was a retrospective observational database study. METHODS: We queried the Kids' Inpatient Database for all children greater than 4 years old and under 20 years old for the years 1997, 2000, 2003, and 2006 who had an intrathecal catheter and pump placed. We then compared demographics and hospital characteristics of patients with and without complications. We performed univariate and multivariate analyses to determine the relative contribution of various factors to the development of complications. RESULTS: We identified 2,843 patients who met our criteria, and 514 of these patients had one or more complications after placement of intrathecal pump/catheter. There were 1.14 complications per patient. The complication rate was 10.2% in 1997, and increased to 21.9% in 2006. Mechanical complications were the most common type of complication in this population, account for nearly two-thirds of all complications occurring. Age, hospital type, hospital size, and admission source were independent predictors of complications. LIMITATIONS: We did not have access to ASA status, operative details, and access to patient charts. CONCLUSIONS: Complication rates after placement of intrathecal pump/catheters have increased in the pediatric population between 1997 and 2006 mainly due to an increase in mechanical complications.


Asunto(s)
Cateterismo/efectos adversos , Bombas de Infusión Implantables/efectos adversos , Infusión Espinal/efectos adversos , Procedimientos Neuroquirúrgicos/efectos adversos , Complicaciones Posoperatorias , Adolescente , Baclofeno/administración & dosificación , Niño , Preescolar , Femenino , Humanos , Masculino , Relajantes Musculares Centrales/administración & dosificación , Espasticidad Muscular/tratamiento farmacológico , Estados Unidos , Adulto Joven
12.
J Phys Chem B ; 114(42): 13381-5, 2010 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-20925353

RESUMEN

In this article, we report non-Arrhenius behavior in the temperature-dependent dc conductivity of alkali ion conducting silicate glasses well below their glass transition temperature. In contrast to the several fast ion-conducting and binary potassium silicate glasses, these glasses show a positive deviation in the Arrhenius plot. The observed non-Arrhenius behavior is completely reproducible in nature even after prolonged annealing close to the glass transition temperature of the respective glass sample. These results are the manifestation of local structural changes of the silicate network with temperature and give rise to different local environments into which the alkali ions hop, revealed by in situ high-temperature Raman spectroscopy. Furthermore, the present study provides new insights into the strong link between the dynamics of the alkali ions and different sites associated with it in the glasses.

13.
Indian J Pathol Microbiol ; 46(3): 466-7, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15025309

RESUMEN

Pleomorphic adenoma of soft palate is extremely rare. A large tumour in soft palate is reported with sleep apnea syndrome. Diagnosis was made by fine needle aspiration cytology and intraoperative consultation by imprint smears, which were confirmed by histopathological and immunohistochemical studies.


Asunto(s)
Adenoma Pleomórfico/complicaciones , Neoplasias Palatinas/complicaciones , Apnea Obstructiva del Sueño/etiología , Adenoma Pleomórfico/patología , Adulto , Humanos , Masculino , Neoplasias Palatinas/patología , Paladar Blando
14.
J Pharm Biomed Anal ; 25(1): 21-30, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11274855

RESUMEN

A normal phase, isocratic LC method was developed for the separation of positional isomers of celecoxib (I) using a chiral column, Chiralpak-AD. The method is useful for the quantification of ortho (II) and meta (III) forms in bulk drugs and formulation samples of celecoxib. The method has been completely validated and proven to be rugged. The limit of detection (LOD) and limit of quantitation (LOQ) of ortho and meta forms were found to be 38 ng and 116 ng respectively. The active pharmaceutical ingredient was extracted from its finished dosage form (capsule) using ethanol. The percentage recoveries of ortho isomer was found to be 99.8--102.7 and 97.8--103.2 and the percentage recoveries of meta isomer was found to be 99.3--102.6 and 99.7--104 in spiked bulk and formulation samples of celecoxib respectively.


Asunto(s)
Antiinflamatorios no Esteroideos/análisis , Cromatografía Liquida/métodos , Sulfonamidas/análisis , Antiinflamatorios no Esteroideos/aislamiento & purificación , Celecoxib , Química Farmacéutica , Estabilidad de Medicamentos , Isoformas de Proteínas/análisis , Isoformas de Proteínas/aislamiento & purificación , Pirazoles , Control de Calidad , Sulfonamidas/aislamiento & purificación
15.
J Pharm Biomed Anal ; 22(6): 949-56, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10857564

RESUMEN

A new reversed-phase, isocratic LC method was developed for the quantitative determination of COX-2 inhibitor celecoxib in bulk drugs and in pharmaceutical dosages. The proposed method is also applicable for the purity evaluation of celecoxib in bulk drugs. 5-Methyl 2-Nitro phenol has been used as internal standard for the quantitative determination of celecoxib. The method has been completely validated and proven to be rugged. The limit of detection (LOD) and limit of quantitation (LOQ) for celecoxib impurities namely, 4-hydrazino benzene sulfonamide (Intermediate I) and 1-(4-methyl phenyl)-4,4.4-trifluro butan-1,3-dione (Intermediate II) were found to be 32.0 and 97 ng. respectively. The active pharmaceutical ingredient was extracted from its finished dosage form (capsule) using methanol. The percentage recoveries ranged from 90.7 to 93.8. The stability studies were performed for celecoxib solution placed on laboratory bench and in refrigerator for hundred days. The samples were found to be stable for the study period.


Asunto(s)
Inhibidores de la Ciclooxigenasa/análisis , Isoenzimas/metabolismo , Prostaglandina-Endoperóxido Sintasas/metabolismo , Sulfonamidas/análisis , Cápsulas , Celecoxib , Cromatografía Líquida de Alta Presión , Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa 2 , Contaminación de Medicamentos , Estabilidad de Medicamentos , Concentración de Iones de Hidrógeno , Pirazoles , Reproducibilidad de los Resultados , Soluciones
16.
J Pharm Biomed Anal ; 22(4): 627-39, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10768352

RESUMEN

Two isocratic liquid chromatography (LC) methods have been developed for the purity estimation and quantitative determination of sibutramine HCl, using 4-chloro aniline and lovastatin as internal standards, respectively. The precision has been checked in terms of F-test variance ratio using latter method as reference. The ratio of variances of the two methods is close to unity, confirming their good precision. The correlation coefficient for linear regression is more than 0.999. The inter and intra-day precision is found to be < 1.3% RSD. The accuracy determined as relative mean error (RME) for the intra-day assay is +/- 1.7%. The enantiomeric separation of sibutramine by chiral chromatography method has been described also. This method is capable of separating the two enantiomers with a selectivity of 1.4 and a resolution of 4.0. Both methods are found to be stability indicating and useful in the quality control of the bulk material.


Asunto(s)
Cromatografía Liquida/métodos , Ciclobutanos/aislamiento & purificación , Antidepresivos/aislamiento & purificación , Estabilidad de Medicamentos , Control de Calidad , Estándares de Referencia , Reproducibilidad de los Resultados , Estereoisomerismo
17.
J Health Care Mark ; 11(1): 23-30, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10110078

RESUMEN

The role of marketing in a health care facility has been a focus of discussion during the past decade. Varied opinions have been expressed about the purpose and contribution of marketing within the health care industry. The authors empirically investigate (1) the extent of marketing orientation in hospitals, (2) the degree of marketing orientation as it relates to hospital characteristics, and (3) the relationship of marketing orientation to hospital performance.


Asunto(s)
Administración Hospitalaria/estadística & datos numéricos , Comercialización de los Servicios de Salud/estadística & datos numéricos , Estudios de Evaluación como Asunto , Cultura Organizacional , Encuestas y Cuestionarios , Estados Unidos
18.
J Hosp Mark ; 6(1): 5-27, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-10116637

RESUMEN

It is about two decades since the marketing scholars identified the need and relevance of marketing in health care organizations. The health care industry itself has been undergoing significant changes brought on by deregulation, declining demand, intraorganizational competition and growth of HMO's and PPO's. Yet, the industry has not fully implemented the marketing concept. For many health care organizations, marketing seems still to mean advertising and public relations as evidenced by an empirical study.


Asunto(s)
Ocupación de Camas/estadística & datos numéricos , Hospitales/clasificación , Comercialización de los Servicios de Salud/estadística & datos numéricos , Publicidad/estadística & datos numéricos , Presupuestos/estadística & datos numéricos , Estudios de Evaluación como Asunto , Capacidad de Camas en Hospitales , Departamentos de Hospitales/estadística & datos numéricos , Hospitales/estadística & datos numéricos , Renta/estadística & datos numéricos , Comercialización de los Servicios de Salud/métodos , Encuestas y Cuestionarios , Estados Unidos
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