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1.
NCHS Data Brief ; (478): 1-8, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37642973

RESUMO

In 2021, 140 million emergency department (ED) visits occurred in the United States (1). During that year, about 4% of children had two or more ED visits in the past 12 months, and 18% of adults had visited the ED in the past 12 months (2,3). This report presents characteristics of ED visits by age group, sex, race and ethnicity, insurance, and mentions of COVID-19, using data from the 2021 National Hospital Ambulatory Medical Care Survey (NHAMCS) (4).


Assuntos
COVID-19 , Adulto , Criança , Estados Unidos/epidemiologia , Humanos , COVID-19/epidemiologia , Serviço Hospitalar de Emergência , Etnicidade
2.
NCHS Data Brief ; (452): 1-8, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36453979

RESUMO

In 2020, an estimated 131 million emergency department (ED) visits occurred in the United States, with 19.0% of adults reporting a visit and 4.7% of children reporting two or more visits in the past 12 months (1-3). In that time, over 20 million cases of COVID-19 caused a disruption in access to and use of care (4). This report presents characteristics of ED visits, including those with mentions of COVID-19, by age group, sex, race and ethnicity, and primary expected source of payment, using data from the 2020 National Hospital Ambulatory Medical Care Survey (NHAMCS)(5).


Assuntos
COVID-19 , Adulto , Criança , Estados Unidos/epidemiologia , Humanos , COVID-19/epidemiologia , Serviço Hospitalar de Emergência , Etnicidade
3.
Environ Sci Technol ; 54(6): 3499-3509, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32100529

RESUMO

Variability in consumer practices and choices is typically not addressed in comparisons of environmental impacts of traditional shopping and e-commerce. Here, we developed a stochastic model to quantify the variability in the greenhouse gas (GHG) footprints of product distribution and purchase of fast-moving consumer goods (FMCGs) via three prevalent retail channels in the United Kingdom (U.K.). We found that shopping via bricks and clicks (click and fulfillment via physical store delivery) most likely decreases the GHG footprints when substituting traditional shopping, while FMCGs purchased through pure players with parcel delivery often have higher GHG footprints compared to those purchased via traditional retail. The number of items purchased and the last-mile travel distance are the dominant contributors to the variability in the GHG footprints of all three retail channels. We further showed that substituting delivery vans with electric cargo bikes can lead to a GHG emission reduction of 26% via parcel delivery. Finally, we showed the differences in the "last mile" GHG footprint of traditional shopping in the U.K. compared to three other countries (China, Netherlands, and the United States), which are primarily caused by the different shares of modes of transport (walking and by car, bus, and bike).


Assuntos
Gases de Efeito Estufa , China , Efeito Estufa , Países Baixos , Reino Unido , Estados Unidos
4.
Environ Sci Technol ; 52(1): 135-144, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29195039

RESUMO

Our study provides an integrated analysis of the variability of greenhouse gas (GHG) footprints of field-grown tomatoes for processing. The global farm-specific data set of 890 observations across 14 countries over a three-year period (2013-2015) was obtained from farms grown under Unilever's sustainable agricultural code. It represents on average 3% of the annual global production of processing tomatoes: insights can be used to help inform corporate sourcing strategies and certification schemes. The median GHG footprint ranged from 18 in Chile to 61 kg CO2-equiv per tonne of tomatoes in India, lower than results reported in other studies. We found that footprints are more consistent within countries than between them. Using linear mixed effect models, we quantified the relative influence of environmental conditions and farm management factors. Key variables were area of production and the method of fertilizer application. GHG footprints decreased with increasing area of production to a threshold of 17.4 ha. Farms using single fertilizer application methods in general had a larger GHG footprint than those using a combination of methods. We conclude that farm management factors should be prioritized for future data collection, and more stringent guidance on acceptable practices is required if greater comparability of outcomes is needed either within a scheme, such as the Unilever's sustainable agriculture code, or between schemes.


Assuntos
Gases de Efeito Estufa , Solanum lycopersicum , Chile , Efeito Estufa , Índia
5.
J Microsc ; 252(2): 100-10, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23889324

RESUMO

We present the rationale for the development of mathematical features used for classification of images stained for selected tight junction proteins. The project examined localization of zonula occludens-1, claudin-1 and F-actin in a model epithelium, Madin-Darby canine kidney II cells. Cytochalasin D exposure was used to perturb junctional localization by actin cytoskeleton disruption. Mathematical features were extracted from images to reliably reveal characteristic information of the pattern of protein localization. Features, such as neighbourhood standard deviation, gradient of pixel intensity measurement and conditional probability, provided meaningful information to classify complex image sets. The newly developed mathematical features were used as input to train a neural network that provided a robust method of individual image classification. The ability for researchers to make determinations concerning image classification while minimizing human bias is an important advancement for the field of tight junction cellular biology.


Assuntos
Actinas/metabolismo , Claudina-1/metabolismo , Processamento de Imagem Assistida por Computador/métodos , Junções Íntimas/metabolismo , Proteína da Zônula de Oclusão-1/metabolismo , Animais , Linhagem Celular , Citocalasina D/metabolismo , Citoesqueleto/metabolismo , Cães , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Imunofluorescência/métodos , Células Madin Darby de Rim Canino , Computação Matemática , Modelos Teóricos
6.
Gen Comp Endocrinol ; 167(1): 60-7, 2010 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-20178800

RESUMO

Selected physiological parameters were monitored over a 4-year period in the Barrow Island euro, Macropus robustus isabellinus, in Western Australia in a study of this species' homeostatic capabilities in an extremely arid habitat where individuals are exposed to high environmental temperatures and a lack of free water for much of the year. Evidence was found of a significant change in the animal's milieu intérieur on only one occasion on Barrow Island: in November 1994, following a protracted 8-month drought. Euros had significantly elevated levels of plasma osmolality, cortisol, anti-diuretic hormone (lysine vasopressin - LVP), and a reduced eosinophil count. This suggests that these animals may have been dehydrated, despite the operation of appropriate physiological responses to water deprivation. Lower eosinophil counts also suggest that immune function may have been suppressed as a result of the elevated corticosteroid levels. Comparisons with the mainland sub-species of the euro revealed the presence of a non-generative normocytic hypochromic anaemia in Barrow Island euros that potentially compromises their aerobic capacity. Barrow Island is Australia's most important A Class Reserve, harbouring 8 species of marsupials, 4 of which are now extinct, or virtually so, on the adjacent mainland. This study reveals the remarkable effectiveness of the euro's homeostatic capacities, however, its future conservation depends on ensuring that potential stress due to declining water availability and environmental change is avoided.


Assuntos
Macropodidae/metabolismo , Estresse Fisiológico , Animais , Água Corporal/metabolismo , Secas , Geografia , Hidrocortisona/metabolismo , Lipressina/metabolismo , Macropodidae/fisiologia , Concentração Osmolar , Radioimunoensaio
7.
J Food Sci ; 74(3): C278-83, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19397713

RESUMO

In this study, the effects of ozonation and the addition of amino acids on rice starches were determined in terms of pasting properties using a rapid visco-analyzer. Results from viscosity analysis showed that 30-min ozone treatment on commercial rice starch exhibited the greatest swelling extent among the treatments and least retrogradation tendency. The control pure oxygen treated sample had the best cooking stability. The addition of lysine (6%) to 30-min ozonated commercial rice starch significantly reduced peak viscosity (PV), minimum viscosity (MV), and final viscosity (FV) by 918, 1024, and 1023 cP, respectively. Moreover, it decreased Ptime, resulting in the faster swelling upon heating and less rigid gel formation upon cooling. Furthermore, the presence of lysine in 30-min ozonated starch isolate (WSI) also significantly reduced PV, MV, FV, pasting time, and total setback (TSB) and produced starch gel with the best cooking stability and the least retrogradation tendency. Ozonated starch exhibited similar pasting properties to those from oxidized starches treated with low concentrations of chemical oxidizing agents. The combination of lysine with ozonation resulted in pasting properties similar to starches treated with high levels of chemical oxidizing agents. The ozonated starch could be used as a thickening agent, whereas ozonated starch with lysine might be an alternative for a highly chemically oxidized starch. Therefore, ozonation alone or the combination of ozonation and addition of lysine might be used to develop new starch ingredients with various functionalities without using typical chemical modifications.


Assuntos
Aminoácidos/administração & dosagem , Oryza/química , Ozônio/administração & dosagem , Amido/química , Fenômenos Químicos , Estabilidade de Medicamentos , Lisina/administração & dosagem , Oxidantes/administração & dosagem , Oxirredução , Oxigênio/administração & dosagem , Viscosidade
8.
J Food Sci ; 74(2): E70-6, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19323744

RESUMO

Four different catfish oil extraction processes were used to extract oil from catfish viscera: process CF1 involved a mixture of ground catfish viscera and water, no heat treatment, and centrifugation; process CF2 involved ground catfish viscera (no added water), heat treatment, and centrifugation; process CF3 involved a mixture of ground catfish viscera and water, heat treatment, and centrifugation; process CF4 involved ground catfish viscera, enzymatic hydrolysis, and centrifugation. Chemical and physical properties of the resulting of catfish oils were evaluated. The CF4 process recovered significantly higher amounts of crude oil from catfish viscera than the other 3 extraction methods. The CF4 oil contained a higher percent of free fatty acid and peroxide values than CF1, CF2, and CF3 oils. Oleic acid in catfish oil was the predominant fatty acid accounting for about 50% of total fatty acids. Weight loss of oils increased with increasing temperatures between 250 and 500 degrees C. All the catfish oil samples melted around -32 degrees C regardless of the extraction methods. The flow behavior index of all the oil samples was less than 1, which indicated that the catfish oils exhibited non-Newtonian fluid behavior. The apparent viscosity at -5 and 0 degrees C was significantly higher (P < 0.05) than those at 5, 10, 15, 20, 25, and 30 degrees C. The average magnitude of activation energy for apparent viscosity of the oil was higher for CF2 than CF1, CF3, and CF4.


Assuntos
Peixes-Gato , Ácidos Graxos não Esterificados/análise , Ácidos Graxos/análise , Óleos de Peixe/química , Óleos de Peixe/isolamento & purificação , Conservação de Alimentos/métodos , Animais , Óleos de Peixe/normas , Carne/análise , Minerais/análise , Peróxidos/análise , Termodinâmica , Tocoferóis/análise , Viscosidade , Água/análise
9.
Environ Monit Assess ; 157(1-4): 137-49, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19023672

RESUMO

Given the alarming global rates of mangrove forest loss it is important that resource managers have access to updated information regarding both the extent and condition of their mangrove forests. Mexican mangroves in particular have been identified as experiencing an exceptional high annual rate of loss. However, conflicting studies, using remote sensing techniques, of the current state of many of these forests may be hindering all efforts to conserve and manage what remains. Focusing on one such system, the Teacapán-Agua Brava-Las Haciendas estuarine-mangrove complex of the Mexican Pacific, an attempt was made to develop a rapid method of mapping the current condition of the mangroves based on estimated LAI. Specifically, using an AccuPAR LP-80 Ceptometer, 300 indirect in situ LAI measurements were taken at various sites within the black mangrove (Avicennia germinans) dominated forests of the northern section of this system. From this sample, 225 measurements were then used to develop linear regression models based on their relationship with corresponding values derived from QuickBird very high resolution optical satellite data. Specifically, regression analyses of the in situ LAI with both the normalized difference vegetation index (NDVI) and the simple ration (SR) vegetation index revealed significant positive relationships [LAI versus NDVI (R (2) = 0.63); LAI versus SR (R (2) = 0.68)]. Moreover, using the remaining sample, further examination of standard errors and of an F test of the residual variances indicated little difference between the two models. Based on the NDVI model, a map of estimated mangrove LAI was then created. Excluding the dead mangrove areas (i.e. LAI = 0), which represented 40% of the total 30.4 km(2) of mangrove area identified in the scene, a mean estimated LAI value of 2.71 was recorded. By grouping the healthy fringe mangrove with the healthy riverine mangrove and by grouping the dwarf mangrove together with the poor condition mangrove, mean estimated LAI values of 4.66 and 2.39 were calculated, respectively. Given that the former healthy group only represents 8% of the total mangrove area examined, it is concluded that this mangrove system, considered one of the most important of the Pacific coast of the Americas, is currently experiencing a considerable state of degradation. Furthermore, based on the results of this investigation it is suggested that this approach could provide resource managers and scientists alike with a very rapid and effective method for monitoring the state of remaining mangrove forests of the Mexican Pacific and, possibly, other areas of the tropics.


Assuntos
Avicennia/crescimento & desenvolvimento , Monitoramento Ambiental/métodos , Geografia , Folhas de Planta/crescimento & desenvolvimento , México , Oceano Pacífico , Rhizophoraceae/crescimento & desenvolvimento
10.
Eye (Lond) ; 23(3): 626-31, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18292785

RESUMO

AIM: To determine whether there is an association between complement factor H (CFH) or LOC387715 genotypes and response to treatment with photodynamic therapy (PDT) for exudative age-related macular degeneration (AMD). METHODS: Sixty-nine patients being treated for neovascular AMD with PDT were genotyped for the CFH Y402H and LOC387715 A69S polymorphisms by allele-specific digestion of PCR products. AMD phenotypes were characterized by clinical examination, fundus photography, and fluorescein angiography. RESULTS: Adjusting for age, pre-PDT visual acuity (VA), and lesion type, mean VA after PDT was significantly worse for the CFH TT genotype than for the TC or CC genotypes (P=0.05). Post-PDT VA was significantly worse for the CFH TT genotype in the subgroup of patients with predominantly classic choroidal neovascular lesions (P=0.04), but not for the patients with occult lesions (P=0.22). For the LOC387715 A69S variant, there was no significant difference among the genotypes in response to PDT therapy. CONCLUSIONS: The CFH Y402H variant was associated with a response to PDT treatment in this study. Patients with the CFH TT genotype fared significantly worse with PDT than did those with the CFH TC and CC genotypes, suggesting a potential relationship between CFH genotype and response to PDT.


Assuntos
Degeneração Macular/tratamento farmacológico , Degeneração Macular/genética , Fotoquimioterapia , Proteínas/genética , Idoso , Idoso de 80 Anos ou mais , Neovascularização de Coroide/tratamento farmacológico , Neovascularização de Coroide/genética , Neovascularização de Coroide/fisiopatologia , Fator H do Complemento/genética , Feminino , Genótipo , Humanos , Degeneração Macular/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Prognóstico , Resultado do Tratamento , Acuidade Visual/genética , Acuidade Visual/fisiologia
11.
J Food Sci ; 73(8): M400-4, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19019121

RESUMO

Antimicrobial activities of chitosan samples with different molecular weights (1333, 432, 201, 131, and 104 kDa) prepared by ozone treatment were examined against 2 Gram-positive bacteria (Listeria monocytogenes and Staphylococcus aureus) and 2 Gram-negative bacteria (Escherichia coli and Pseudomonas fluorescen) to investigate the effect of chitosan's molecular weight and concentration on the inhibition of bacterial growth. Antimicrobial activity of chitosan varied depending on the molecular weight, concentration of chitosan, and type of microorganism. Generally, the effectiveness of the chitosans significantly increased with increasing chitosan concentration, regardless of molecular size and types of bacteria. Chitosan with molecular weights ranging from 104 to 201 kDa showed relatively greater antimicrobial activity against L. monocytogenes, S. aureus, and P. fluorescen; whereas for E. coli, intermediate molecular weight chitosan was more effective in growth inhibition than lower or higher molecular weight chitosan particularly at 0.1% concentration.


Assuntos
Antibacterianos/farmacologia , Astacoidea/química , Quitosana/farmacologia , Ozônio/química , Polímeros/química , Animais , Quitosana/química , Escherichia coli/efeitos dos fármacos , Listeria monocytogenes/efeitos dos fármacos , Peso Molecular , Pseudomonas fluorescens/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Viscosidade
12.
J Food Sci ; 73(8): S418-23, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19019130

RESUMO

Selected quality characteristics of fresh-cut sweet potatoes (FCSP) coated with chitosan were evaluated during 17-d refrigerated storage. The FCSP cubes were coated with a solution (1%, w/v) of chitosan having 470 or 1110 kDa. Color (L*, a*, b*) values of uncoated and chitosan-coated FCSP during storage were generally affected by storage time as well as coating treatments (P < 0.05). No significant changes in color lightness (L*) of 470 kDa-coated FCSP were observed during the 17-d storage. During days 3 to 17, 470 kDa-coated FCSP had significantly higher redness (a*) and yellowness (b*) values than did uncoated and 1110 kDa-coated FCSP. Texture firmness of uncoated and chitosan-coated FCSP exhibited minimal changes during the 17-d storage. Although actual weight loss values (%) of uncoated and chitosan-coated FCSP were not significantly different at day 17, the weight loss difference (%) between day 3 and day 17 for uncoated FCSP (3.02%) was slightly higher compared to those (2.24% to 2.26%) of chitosan-coated FCSP. The initial total aerobic count was 4.7 log(10) CFU/g which then gradually increased to 8.54 and 9.67 log(10) CFU/g after 17 d of storage for 470 kDa-coated and uncoated FCSP, respectively. After day 6, the total aerobic counts of uncoated FCSP were higher than those of 470 kDa-coated FCSP. The yeast and mold count of chitosan-coated FCSP was about 2.5 log(10) CFU/g at day 17. Overall, consumers could not differentiate between 470 kDa-coated FCSP at day 17 and uncoated FCSP at day 0.


Assuntos
Quitosana , Temperatura Baixa , Manipulação de Alimentos/métodos , Conservação de Alimentos/métodos , Ipomoea batatas , Cor , Ipomoea batatas/química , Ipomoea batatas/microbiologia , Controle de Qualidade , Sensação , Fatores de Tempo
13.
J Food Sci ; 73(5): C373-7, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18576982

RESUMO

This study assessed the effects of amino acid additives, aspartic acid, leucine, lysine, and methionine, on the pasting and thermal characteristics of white- and orange-fleshed Beauregard sweet potato starches. A rapid visco analyzer 3D was used to determine pasting properties. In comparing pasting characteristics, starch from orange-fleshed sweet potato was found to be easier to cook, had a lower potential for retrogradation, and was less stable during heating than the white-fleshed sweet potato starch. The RVA analysis showed that the charged amino acids, aspartic acid and lysine, altered pasting characteristics of the 2 starches more than the neutral amino acids, leucine and methionine. Aspartic acid had similar effects on both starches, making them less stable during cooking and lowering the potential for retrogradation. Lysine, when added to the orange-fleshed sweet potato starch, decreased the breakdown, allowing for more stability during cooking. This study showed that pasting properties of sweet potato starches can be altered by the addition of amino acids.


Assuntos
Aminoácidos/farmacologia , Manipulação de Alimentos/métodos , Géis , Ipomoea batatas/química , Amido/química , Ácido Aspártico/farmacologia , Fenômenos Químicos , Físico-Química , Culinária , Géis/análise , Géis/química , Leucina/farmacologia , Lisina/farmacologia , Metionina/farmacologia , Especificidade da Espécie , Amido/análise , Viscosidade
14.
J Food Sci ; 73(1): C19-23, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18211344

RESUMO

Capabilities of crude soy oil, degummed oil, gum, and defatted soy flour extract in preventing the oxidation of menhaden oil and its omega-3 fatty acids, DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid), during heating were evaluated. The menhaden oil mixed with defatted soy flour extract demonstrated the greatest stability by producing the lowest TBA reactive oxidation products and retaining the highest concentrations of DHA and EPA after heating at 150 degrees C for 30 min. A range of 62.8% to 71.5% of DHA and 67.7% to 75.9% of EPA remained in the fish oil with defatted soy flour extract, while only 29.9% of DHA and 37.2% of EPA were retained in the fish oil with no addition. Stabilizing capability from highest to lowest was defatted flour extract > gum > degummed oil = crude oil. The defatted flour extract had the highest level of total phenolic content (11.3 microg catechin equivalent/g), while crude oil, degummed oil, and gum contained 7.1, 6.1, and 6.0 microg catechin equivalent/g, respectively. The level of isoflavones in the defatted soy flour extract was 55 mg/g, which was over 100 times higher than in the crude oil or gum. Although isoflavones were not detected in the degummed oil, it contained the highest level of tocopherols (414 mug/g), whereas the lowest level (215 microg/g) was found in the defatted flour extract. The order of free radical scavenging capability measured from high to low was the defatted soy flour extract, crude oil, degummed oil, and gum.


Assuntos
Antioxidantes/farmacologia , Ácidos Graxos Ômega-3/análise , Óleos de Peixe/química , Manipulação de Alimentos/métodos , Fenóis/farmacologia , Óleo de Soja/análise , Ácidos Docosa-Hexaenoicos/análise , Ácidos Docosa-Hexaenoicos/metabolismo , Relação Dose-Resposta a Droga , Ácido Eicosapentaenoico/análise , Ácido Eicosapentaenoico/metabolismo , Ácidos Graxos Ômega-3/metabolismo , Farinha/análise , Temperatura Alta , Oxirredução , Extratos Vegetais/análise , Extratos Vegetais/química , Óleo de Soja/química , Glycine max/química , Fatores de Tempo
15.
Gen Comp Endocrinol ; 155(2): 378-85, 2008 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-17720162

RESUMO

Seasonal variations in rates of water turnover were measured over a 7-year period in four species of macropodid marsupials (Lagorchestes conspicillatus, Bettongia lesueur, Petrogale lateralis and Macropus robustus isabellinus), on Barrow Island off the arid Pilbara coast of Western Australia. These ranged from over 100 mL kg(-0.82) d(-1) in wet seasons to as low as 28.2 mL kg(-0.82) d(-1) in dry seasons in the Spectacled hare wallaby, L. conspicillatus. Plasma osmolality increased significantly in both Barrow Island euros (M. robustus isabellinus) and Spectacled hare wallabies in November 1994, in the driest year yet recorded on the island. In contrast, there was no change in plasma osmolality of the other two species (Black-footed rock wallaby, P. lateralis and Lesueur's burrowing bettong, B. lesueur) that exploit cool and humid thermal refugia such as caves and underground warrens to avoid diurnal temperature extremes. Plasma levels of the marsupial antidiuretic hormone (ADH), lysine vasopressin (LVP), were for the most part below the detectable limit of the assay of 0.41 pg mL(-1) in rock wallabies and bettongs, but reached high levels of 16.7+/-4.6 pg mL(-1) and 20.25+/-5.1 pg mL(-1) in euros and hare wallabies, respectively, in dry seasons. LVP levels were positively correlated with plasma osmolality in both euros and hare wallabies, and negatively correlated with total body water content in euros, supporting its rôle as an antidiuretic hormone in these two species. The study highlights the importance of environmental features, such as caves and underground warrens, which are critical for the long-term survival of endangered species such as the Black-footed rock wallaby and the Lesueur's bettong. These species appear to lack ADH-controlled renal systems for the conservation of body water and are thus dependent on behavioural strategies for the maintenance of fluid homeostasis in arid environments.


Assuntos
Água Corporal/metabolismo , Rim/fisiologia , Lipressina/sangue , Macropodidae/metabolismo , Equilíbrio Hidroeletrolítico/fisiologia , Adaptação Fisiológica , Animais , Clima Desértico , Meio Ambiente , Homeostase/fisiologia , Estudos Longitudinais , Concentração Osmolar , Estações do Ano , Especificidade da Espécie
16.
J Food Sci ; 72(9): C504-8, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18034711

RESUMO

Capabilities of methanol extracts from oregano and rosemary in retarding oxidation of long-chain polyunsaturated fatty acids, docosahexaenoic acid C22:6 (DHA) and eicosapentaenoic acid C20:5 (EPA), in menhaden oil were investigated. The fish oils after mixing with the extracts at different concentrations were oxidized in an accelerated study by heating at 150 degrees C for 30 min or incubating at 60 degrees C for 5 d. After heating at 150 degrees C, only 15.9% of DHA and 18.5% of EPA remained in the fish oil without extract, while 38.8% to 65.9% of DHA and 44.7% to 69.0% of EPA were retained in the fish oil mixed with 1% to 5% of oregano extract. The highest retained DHA (56.9%) and EPA (58.0%) in the fish oils mixed with rosemary extract were observed at 2.5% addition. Increasing rosemary extract to 5% lowered its capability of inhibiting DHA and EPA oxidation. After incubation at 60 degrees C for 5 d, the highest inhibition capability was also found at 2.5% of added rosemary extract, and the oil retained 88.2% DHA and 88.3% EPA. However, only 18.8% DHA and 23.6% EPA were retained in the fish oil mixed with 5% of oregano extract and no DHA and EPA were detected in the fish oil without extract after 5-d incubation at 60 degrees C. Thus, antioxidant activity of the rosemary extract was greater than that of oregano extract, but was sensitive to heat. The rosemary extract also demonstrated higher DPPH (2,2'-diphenyl-1-picrylhydrazyl) free radical scavenging capability, which was approximately 3 times higher than oregano extract, although there was no significant difference in the total phenolic contents between both extracts.


Assuntos
Antioxidantes/química , Ácidos Graxos Ômega-3/química , Óleos de Peixe/química , Origanum , Extratos Vegetais/química , Rosmarinus , Ácidos Docosa-Hexaenoicos/química , Ácido Eicosapentaenoico/química , Manipulação de Alimentos/métodos , Conservação de Alimentos/métodos , Sequestradores de Radicais Livres/química , Temperatura Alta , Oxirredução , Fenóis/química , Temperatura , Fatores de Tempo
17.
J Food Sci ; 72(9): C522-6, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18034714

RESUMO

Currently, depolymerization and decolorization of chitosan are achieved by chemical or enzymatic methods, which are time consuming and expensive. Ozone has been shown to be able to degrade macromolecules and remove pigments due to its high oxidation potential. In this study, the effects of ozone treatment on depolymerization and decolorization of chitosan were investigated. Crawfish chitosan was ozonated in water and acetic acid solution for 0, 5, 10, 15, and 20 min at room temperature with 12 wt% gas. In this study, the effects of ozone treatment on depolymerization and decolorization of chitosan were investigated by measuring the molecular weight, viscosity, and color of chitosan. The color of ozone-treated chitosan was analyzed using a Minolta spectrophotometer. The degree of deacetylation was determined by a colloid titration method. Molecular weight of ozone-treated chitosan in acetic acid solution decreased appreciably as the ozone treatment duration increased. Ozonation for 20 min reduced the molecular weight of the chitosan by 92% (104 kDa) compared to the untreated chitosan (1333 kDa) with a decrease in viscosity of the chitosan solution. Ozonation for 5 min markedly increased the whiteness of chitosan with a molecular weight of 432 kDa; however, further ozonation resulted in development of yellowness. In the case of the ozonation in water, there were no significant differences in the molecular weight and color between ozone-treated chitosans. This study showed that ozone can be used to modify molecular weight and remove pigments of chitosan without chemical use in a shorter time and with less cost.


Assuntos
Astacoidea/química , Quitosana/química , Ozônio/química , Pigmentos Biológicos/química , Ácido Acético/química , Acetilação , Análise de Variância , Animais , Cor , Estudos de Viabilidade , Peso Molecular , Fatores de Tempo , Viscosidade , Água
18.
J Food Sci ; 72(1): C084-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17995877

RESUMO

Thermal properties of conventionally and ohmically heated rice starch and rice flours at various frequencies and voltages were studied. There was an increase in gelatinization temperature for conventionally heated rice starches since they were pregelatinized and became more rigid due to starch-chain interactions. In addition, there was a decrease in enthalpy (energy needed) for conventionally and ohmically heated starches during gelatinization; thus, the samples required less energy for gelatinization during DSC analysis. Ohmically heated commercial starch showed the greatest decrease in enthalpy probably because of the greatest extent of pregelatinization through ohmic heating. Brown rice flour showed the greatest gelatinization temperature resulting from the delay of starch granule swelling by lipid and protein. Enthalpy of ohmically heated starches at 20 V/cm was the lowest, which was most likely due to the lower voltage resulting in a more complete pregelatinization from a longer heating time required to reach 100 degrees C. Ohmic treatment at 70 V/cm decreased onset gelatinization temperature of white flour; therefore, it produced rice flour that swelled faster, whereas the conventionally heated sample showed a better thermal resistance.


Assuntos
Farinha/análise , Manipulação de Alimentos/métodos , Temperatura Alta , Oryza/química , Amido/química , Varredura Diferencial de Calorimetria , Fenômenos Químicos , Físico-Química , Géis
19.
Bioprocess Biosyst Eng ; 30(2): 123-34, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17235605

RESUMO

The selection of appropriate operating conditions for bioprocessing is complex due to the large number of interacting stages and variables. Bioprocesses also operate under tight regulation and therefore tools to assist bioprocess design are of significant utility. Conventional approaches for the analysis of variable sensitivities are inadequate. We propose the use of global sensitivity analysis to determine the level of importance of each variable and their interactions. Once key variables have been determined, the designer may focus on the most significant subset. Two case studies are used to demonstrate the applicability of the approach. Each is based on centrifugation and determines the impact of flow-rate, feed viscosity, density difference and particle size, while performance is assessed by supernatant clarification. Significant differences in sensitivities were found between the two studies due to the different feed material properties. Variable sensitivities were found to be system-specific and provide insight for potential operating strategies.


Assuntos
Algoritmos , Bioquímica/métodos , Centrifugação/métodos , Técnicas de Química Combinatória/métodos , Análise de Injeção de Fluxo/métodos , Modelos Biológicos , Modelos Químicos , Simulação por Computador , Microbiologia Industrial/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Br Dent J ; 191(5): 256-9, 2001 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-11575761

RESUMO

AIM: The aim of the study was to find out to what extent children are involved in consenting to their dental care. METHODS: It was conducted using a structured interview with 60 8-13-year-old children. In the control group, verbal consent was given by the parent, whilst in the study group written consent was given by the parent and verbal assent by the patient. Interviews were conducted after dental treatment. RESULTS: The findings indicate that children in the study group felt they were more involved in deciding about their dental treatment compared with the control group. CONCLUSION: Children want to be more involved in consenting to their dental treatment.


Assuntos
Assistência Odontológica para Crianças/psicologia , Consentimento Livre e Esclarecido , Adolescente , Distribuição de Qui-Quadrado , Criança , Feminino , Guias como Assunto , Humanos , Entrevistas como Assunto , Masculino , Participação do Paciente
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