Physical and chemical characteristics of PM2.5 and its toxicity to human bronchial cells BEAS-2B in the winter and summer / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

With the increasing occurrence of haze during the summer, the physicochemical characteristics and toxicity differences in PM2.5 in different seasons are of great concern. Hangzhou is located in an area that has a subtropical monsoon climate where the humidity is very high during both the summer and winter. However, there are limited studies on the seasonal differences in PM2.5 in these weather conditions. In this test, PM2.5 samples were collected in the winter and summer, the morphology and chemical composition of PM2.5 were analyzed, the toxicity of PM2.5 to human bronchial cells BEAS-2B was compared, and the correlation between PM2.5 toxicity and the chemical composition was discussed. The results showed that during both the winter and summer, the main compounds in the PM2.5 samples were water-soluble ions, particularly SO42-, NO3-, and NH4+, followed by organic components, while heavy metals were present at lower levels. The higher the mass concentration of PM2.5, the greater its impact on cell viability and ROS levels. However, when the mass concentration of PM2.5 was similar, the water extraction from the summer samples showed a greater impact on BEAS-2B than that from the winter samples. The cytotoxicity of PM2.5 was closely associated with heavy metals and organic pollutants but less related to water-soluble ions.

Evaluation of physico-chemical characteristics of fresh, refrigerated and frozen Lacaune ewes' milk / Avaliação das características físico-químicas de leite fresco, resfriado e congelado de ovelhas Lacaune

The production of ewe milk is seasonal and milk yield per animal is low, even in specialized animals. This study aimed to verify the possibility of preserving bulk tank milk for seven days under cooling (5°C) and freezing (-5°C), verify the influence of cooling treatments and of the months of the year on the physical and chemical characteristics of the product. The chemical composition of milk, including the fat, protein, lactose and total solids contents, was not altered by cooling and freezing. Protein and lactose contents varied according to the months of the year. The average percentage and standard deviation of fat, protein, lactose and total solids was 8.10±1.30, 5.22±0.37, 4.43±0.23 and 19.34±1.54, respectively. The density, pH, titratable acidity, as well as alcohol and heat stability tests were significantly influenced by the treatments used (P < 0.05), but no differences were found between fresh and frozen milk. Prolonged refrigeration caused an increase in acidity and decrease in pH, with a consequent reduction in the stability of milk. These results demonstrated that freezing does not affect the chemical composition and physical characteristics of milk in nature and it could be a solution for the producer and the sheep milk industry...

O leite ovino, mesmo no caso de raças especializadas, apresenta sazonalidade de produção e baixa produtividade por fêmea. Em função disso, o objetivo do presente estudo foi verificar a possibilidade de conservação do leite fresco, por um período de sete dias, sob refrigeração e congelamento, verificando a influência dos tratamentos aplicados, e dos meses do ano, sobre as características físico-químicas do produto. A composição química, incluindo gordura, proteína, lactose e sólidos totais, não sofreu alterações com o resfriamento e congelamento do leite, contudo os teores de proteína e lactose variaram durante os meses do ano. O percentual médio de gordura, proteína, lactose e sólidos totais foi de 8,10±1,30, 5,22±0,37, 4,43±0,23 e 19,34±1,54, respectivamente. A densidade, o pH, a acidez titulável e as provas de estabilidade ao álcool e ao calor sofreram influência significativa dos tratamentos aplicados (P<0,05), não havendo diferenças entre o leite fresco e o leite congelado. O resfriamento prolongado causou aumento da acidez e diminuição do pH, com a consequente diminuição da estabilidade do leite. Os resultados do presente estudo demonstram que o congelamento não afeta a composição química e as características físicas do leite in natura, podendo ser uma solução para o produtor e para a indústria de leite ovino...

Qualidade da carne de frangos caipiras abatidos em diferentes idades / Quality meat in chicken country slaughter different ages

Neste trabalho, foram avaliadas as características físico-químicas e de composição centesimal da carne de frangos machos de três linhagens utilizadas para criação semi-intensiva: Redbro Cou Nu - Vermelho de Pescoço Pelado (Pescoço Pelado); Redbro Plumé - Vermelho de Pescoço Emplumado (Pesadão) e Gris Barre Plumé (Carijó). Foram analisadas diferenças em relação à linhagem e à idade de abate (70, 85 e 110 dias). Na carne do peito, não foi verificado efeito de linhagem sobre os parâmetros de cor (L*, a* e b*) e pH final. Houve comportamento diferenciado para as aves em relação a qualidade da carne do peito, com menores valores de maciez para linhagem Pesadão e de Perda de Peso por Cozimento para linhagem Carijó. A linhagem Carijó apresentou, para a carne de peito aos 110 dias, os menores valores de umidade e as maiores médias de proteína. Os valores de proteina reduziram para linhagem Pescoço Pelado a partir de 85 dias. Na coxa, a partir de 110 dias, foi verificada redução dos valores de L* (luminosidade) e aumento das médias de a* (vermelho). Os valores de força de cisalhamento e extrato etéreo aumentaram para peito e coxa a partir dos 110 dias. As linhagens Pesadão e Pescoço Pelado apresentaram de forma geral, melhores aspectos físico-quimicos, que são os atributos de maior preferência pelo consumidor em função deste tipo de produto.

The objective of this work was to evaluate the physical and chemical characteristics and composition of meat from male broilers from three strains used for the semi-intensive development: Redbro cou nu - Red naked neck (Label Rouge); Redbro plume - Red neck feathered (Pesadão) and Gris Barre plume (Carijó). We analyzed differences in relation to genetic and slaughter age (70, 85 and 110 days). There was no effect of strain on the color parameters (L * a * b *) and final pH of breast meat. There was different behavior for broilers to quality of breast meat with lower tenderness values for strain Pesadão and Cooking Loss for a strain Carijó. The Carijó line presented the lowest humidity and the highest average protein values for breast meat at 110 days. The protein values reduced in the Label Rouge strain from 85 days forward. In the thigh, decreased levels of L* (brightness) and increase in the average a* (redness) was found from 110 days forward. The Shear Force and ethereal extract for breast and thigh increased from 110 days forward. Pesadão and Label Rouge strains generally presented better physical-chemical attributes, which are preferred by consumers due to this type of product.

Influência do sol nas características fisicas e químicas da tangerina 'Ponkan' cultivada no oeste do Paraná / Sun influence on the physical and chemical characteristics of 'Ponkan' tangerine cultivated in the west of Paraná state

A 'Ponkan' (Citrus reticulata Blanco) é uma das tangerinas mais produzidas no Brasil e muita apreciada pelo consumidor brasileiro. Tendo em vista a sua alta aceitação, há preocupação em se produzir frutos de boa qualidade. Entre os fatores que interferem na qualidade dos frutos podemos citar, como exemplo, a radiação solar. Objetivou-se, neste trabalho, avaliar as características físicas e químicas de frutos de tangerina 'Ponkan', cultivados no oeste do Paraná e colhidos em dois quadrantes da planta, um de maior incidência solar (leste-oeste) e outro de menor incidência (norte-sul). Para as análises físicas determinou-se: o peso do fruto, da casca e dos gomos, diâmetro transversal e longitudinal. Nas análises químicas foram avaliados: o pH, teor de sólidos solúveis totais (SST), acidez total titulável (ATT), relação SST/ATT e teor de ácido ascórbico. Pôde-se verificar pelos resultados obtidos que os frutos desenvolvidos no quadrante leste-oeste das plantas, onde ocorre maior incidência solar, apresentaram maior peso (212,86 g) e diâmetro longitudinal (74,42 mm) quando comparados com frutos do quadrante de menor incidência solar (180,30 g e 67,75 mm, respectivamente). Porém, nas características químicas não observaram diferenças que pudessem interferir no sabor dos frutos.

'Ponkan' is one of the most produced tangerines in Brazil and very appreciated by Brazilian consumers. Having in view its acceptance, there is a concern in producing fruits of high quality. Among the factors that interfere with the quality of the fruits, we can mention, as an example, the solar radiation. This work had the aim of evaluating the physical and chemical characteristics of 'Ponkan' tangerine (Citrus reticulata Blanco), cultivated in the west of Paraná and harvested in two quadrants of the plant, one of higher solar incidence (east-west) and the other of lower incidence (north-south). The physical analyses were the weight of the fruit, peel, and segment, as well the transverse and longitudinal diameter. In the chemical assay we evaluated the pH, content of total soluble solids (TSS), total titratable acidity (TTA), TSS/TTA ratio and content of ascorbic acid. It was verified by the results obtained, that the fruits that grew at the quadrant east-west of the plants, where a higher solar incidence occurs, presented higher weight (212.86 g) and longitudinal diameter (74.42 mm) when compared to fruits of the quadrant of lower solar incidence (180.30 g and 67.75 mm, respectively). However, regarding the chemical characteristics, no difference was observed which could interfere with the flavor of the fruits.

Variaçäo de alguns parâmetros do mel de melato em relaçäo ao mel floral / Comparison of some components between floral honey and honeydew honey

O mel de melato é produzido a partir de secreçöes de partes vivas das plantas difere do mel floral em vários aspectos. Foram analisadas 14 amostras de mel floral e 11 amostras de mel de melato provenientes de Minas Gerais e de Santa Catarina, assim classificadas de acordo com os métodos de Kirkood e de White. Foram realizadas as determinaçöes de pH, reaçäo de Lund, viscosidade e condutividade. Foi aplicado o teste exato de Fisher que demonstrou haver associaçäo entre mel de melato e pH acima de 4,2, reaçäo de Lund abaixo de 0,6 e viscosidade acima de 19,4. Foram analisadas misturas contendo diferentes proporçöes de mel de melato em mel floral e determinados valores para polarimetria, condutividade, pH, resíduo mineral fixo, açúcares redutores de viscosidade. Á medida que aumentou a concentraçäo do mel de melato houve uma alteraçäo significativa nos valores das variáveis analisadas, verificada pelo coeficiente de regressäo b. Foi demonstrado que algumas medidas como pH e viscosidade podem ser aplicadas como critério de diferenciaçäo entre estes dois tipos de mel. (AU)

Honeydew honey differs of the floral honey in many aspects. In order to check that eleven honeydew honey and fourteen floral honey were analysed for pH, Lund reaction, conductivity and viscosity. The Fisher test was applied to check if there was any association between the kind of honey and the quantitative aspects of this study. It was demonstrated that there is association between honeydew honey and the pH above 4,2, Lund reaction below 0,6 mL and viscosity above 19,4. In order to study the effects of a gradative addition of honeydew honey on floral honey and its characteristics such as polarimetry, conductivity, pH, ashes, reducing sugars and viscosity, a linear regression analysis of these characteristics, was done using a blend of both kind of honey. It was observed by the regression coefficient b that the floral honey mixed with honeydew honey showed a significative modification of variables studied when the concentration of honeydew honey was increased. (AU)

Physical and Chemical Characteristics and Peptide Mapping of Recombinant Human GM-CSF / 中国肿瘤生物治疗杂志

The plysical and chemical characteristics of recombinant human GM - CSF (rhGM - CSF) were studied separatly. rhGM - CSF was treated by GdHCl, reduced by DTT, and the disulfide bond was blocked by idoacetamide. The results showed that the samples aren' t homogeneous in UV absorption spectrum and RP-HPLC analysis after treatment by DTT. There was no remarkable differences in the results of the analysis of SDS-PAGE electrophoresis and western blot between treated and untreated rhGM - CSF samples. The effect of GdHCl on GM-CSF was reversible in all above tests; In peptide mapping analysis, the digestion of the samples with blocked disulfide bond by CNBr and protease is more complete than that without any treatment.