scholarly journals Packaging and Conditioning Influence Concerning the Extension of Validity Term

Author(s):  
Camelia CIOBAN ◽  
Diana RABA

In the paper studied the possibility of extending the validity term of bakery products(croissant) by slowing the aging process them. For this purpose investigate sorts were packed in impermeable materials to water and water vapor while were stored at temperatures ranging between 15-20°C and relative air humidity below 70 %. By preserving the croissants under proper conditions in special packing: PE, PP, PP sterilized, paraffin paper, ethylic alcohol treated paper and complex material, the validity term has been extended to 7 days at most, when the first depreciation signs of sensorial (taste, colour, smell),and physical (consistency-the core becomes brittle, humidity-the water quantity lowers significantly) properties become evident. The smooth and rigid crust becomes wrinkled, elastic and soft, the odour and the taste gradually disappear and the taste becomes flat or stuffy and sometimes even sour. The introduction of ethylic alcohol as well as the packing in proper materials determines the extension of croissant validity term to 30 days when the first signs of mould appear.

2019 ◽  
Vol 224 ◽  
pp. 03001
Author(s):  
Igor Ivanov ◽  
Oksana Ivanova

Based on a thermodynamic approach, a mathematical model of charge transfer processes in the polymeric ionites (ion-exchange materials) during the water vapor sorption was developed. Theoretical dependences of the resistance of a polymeric ionite on the relative air humidity over the range 10-100% at physically reasonable values of the parameters of the system were obtained. The comparison of theoretical and experimental dependences has been performed. Possible reasons for and criteria of the phase transitions that lead to stepwise change of ionite resistance were discussed. The developed mathematical model adequately describes the available experimental data and allows formulating practical recommendations on selecting optimal polymeric coatings for the electrode units of molecular-electronic humidity gauges.


2000 ◽  
Vol 25 (4) ◽  
pp. 329-330
Author(s):  
R.J.B. Hemler ◽  
G.H. Wieneke ◽  
P.H. Dejonckere

Author(s):  
R. S. Oliveira ◽  
K. B. A. Pimentel ◽  
M. L. Moura ◽  
C. F. Aragão ◽  
A. S. Guimarães-e-Silva ◽  
...  

Abstract Cutaneous leishmaniasis (CL) is a neglected tropical disease with a wide distribution in the Americas. Brazil is an endemic country and present cases in all states. This study aimed to describe the occurrence, the underlying clinical and epidemiological factors, and the correlation of climatic variables with the frequency of reported CL cases in the municipality of Caxias, state of Maranhão, Brazil. This is a retrospective and descriptive epidemiological study based on data extracted from the Brazilian Information System of Diseases Notification, from 2007 to 2017. Maximum and minimum temperature, precipitation, and relative air humidity data were provided by the Brazilian National Institute of Meteorology. A total of 201 reported autochthonous CL cases were analyzed. The predominance of cases was observed in males (70.1%). The age range between 31 and 60 years old was the most affected, with 96 cases (47.9%). Of the total number of registered cases, 38.8% of the affected individuals were engaged in agriculture-related activities. The georeferenced distribution revealed the heterogeneity of disease occurrence, with cases concentrated in the Western and Southern regions of the municipality. An association was detected between relative air humidity (monthly mean) and the number of CL cases per month (p = 0.04). CL continues to be a concerning public health issue in Caxias. In this context, there is a pressing need to strengthen measures of prevention and control of the disease through the network of health services of the municipality, considering local and regional particularities.


Plants ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 134
Author(s):  
Sabine Stuerz ◽  
Folkard Asch

Predictions of future crop growth and yield under a changing climate require a precise knowledge of plant responses to their environment. Since leaf growth increases the photosynthesizing area of the plant, it occupies a central position during the vegetative phase. Rice is cultivated in diverse ecological zones largely differing in temperature and relative air humidity (RH). To investigate the effects of temperature and RH during day and night on leaf growth, one variety (IR64) was grown in a growth chamber using 9 day/night regimes around the same mean temperature and RH, which were combinations of 3 temperature treatments (30/20 °C, 25/25 °C, 20/30 °C day/night temperature) and 3 RH treatments (40/90%, 65/65%, 90/40% day/night RH). Day/night leaf elongation rates (LER) were measured and compared to leaf gas exchange measurements and leaf area expansion on the plant level. While daytime LER was mainly temperature-dependent, nighttime LER was equally affected by temperature and RH and closely correlated with leaf area expansion at the plant level. We hypothesize that the same parameters increasing LER during the night also enhance leaf area expansion via shifts in partitioning to larger and thinner leaves. Further, base temperatures estimated from LERs varied with RH, emphasizing the need to take RH into consideration when modeling crop growth in response to temperature.


2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
M E L Brandao ◽  
B A L F Braga ◽  
M L C Martins ◽  
P L A A Pereira

Abstract Santos is a seaboard Brazilian city recognized by its port activity where the road and rail infrastructure along with the large transportation operation, displays an important factor to contribute with all kinds of toxic and air pollutants. Recent studies have suggested associations between air pollution and various birth outcomes. Pollutant gases such as NOx, O3 and particulate matter PM2,5, PM10 have been cited as factors involved in such outcomes. The present study aims to assess the relationship between atmospheric pollutants and perinatal outcomes in the city of Santos from Jan. 2012 to Dec. 2015. Cross-sectional study that analyzed 10.319 singleton births in an area set with 2 km radius of the monitoring stations. Birth weight and information on mother and pregnancy were obtained at the Brazilian “Born Alive National Information System”. Daily records of air pollutants (PM10, PM2.5, NO2 and O3), temperature and relative air humidity, for the study period, were obtained from São Paulo State Environmental Agency (CETESB). Associations between preterm birth and air pollutants mean levels at each gestational trimester were investigated using multiple logistic regression model controlled by the variables: infant sex, type of delivery, maternal education. prenatal care, and number of previous live births, temperature and relative air humidity. NO2 e PM2,5 was not associated with preterm birth. O3 was significantly associated in the first trimester in the fourth quartile (OR = 1,47 CI 95% 1,05; 2,07). PM10 was significantly associated in the first trimester for the fourth quartile (OR = 1,28 CI 95% 1,00; 1,64), second trimester for the second quartile (OR = 1,37 CI 95% 1,07; 1,77). Conclusions the results shows evidence that maternal exposure to air pollution especially during the first trimester of pregnancy may contribute to preterm birth. Further actions are needed towards controlling air pollution are strongly recommended for promoting early-life health. Key messages This is the first research of this kind that was made in Santos. It brings important evidence of the impact in the life of the population, especially those whose is not even born yet. It can be used as a resource to guide public policies in health, especially the guidelines that dictate the concentration of air pollutants and air quality.


2021 ◽  
Vol 83 (3) ◽  
pp. 277-283
Author(s):  
V. Yu. Borodulin ◽  
V. N. Letushko ◽  
M. I. Nizovtsev ◽  
A. N. Sterlyagov

2014 ◽  
Vol 60 (2) ◽  
pp. 105-110 ◽  
Author(s):  
Brena Melo ◽  
Melania Amorim ◽  
Leila Katz ◽  
Isabela Coutinho ◽  
José Natal Figueiroa

Objective: The present study aimed at assessing the association between environmental temperature and the relative humidity of the air with frequency of hypertensive disorders of pregnancy. Methods: A prospective and retrospective, descriptive, ecological study was held at a teaching maternity in Recife, Brazil. Data from all 26.125 pregnant women admitted between 2000 and 2006 were analysed and 5.051 had the diagnosis of hypertensive disorder of pregnancy. The incidence percentages were calculated monthly per deliveries. Data on mean monthly temperature and relative humidity of the air were collected and monthly comparisons were conducted. February was chosen as the reference month due to its lowest incidence of the disease. The relative chance of hypertensive disorders of pregnancy for each other month was estimated by odds ratio and Pearson's correlation coefficient was used to calculate the relation between the incidence of hypertensive disorders of pregnancy and the mean monthly temperature and relative air humidity. Results: February presented the lowest mean monthly incidence (9.95%) and August the highest (21.54%). Pearson correlation coefficient revealed a higher incidence of hypertensive disorders of pregnancy in the cooler months (r= -0.26; p=0.046) and no significant effect of relative air humidity (r=0.20; p=0.128). Conclusion: The incidence of hypertensive disorders of pregnancy may be affected by variations in temperature, increasing during cooler periods.


Author(s):  
Gustavo H. da Silva ◽  
Santos H. B. Dias ◽  
Lucas B. Ferreira ◽  
Jannaylton É. O. Santos ◽  
Fernando F. da Cunha

ABSTRACT FAO Penman-Monteith (FO-PM) is considered the standard method for the estimation of reference evapotranspiration (ET0) but requires various meteorological data, which are often not available. The objective of this work was to evaluate the performance of the FAO-PM method with limited meteorological data and other methods as alternatives to estimate ET0 in Jaíba-MG. The study used daily meteorological data from 2007 to 2016 of the National Institute of Meteorology’s station. Daily ET0 values were randomized, and 70% of these were used to determine the calibration parameters of the ET0 for the equations of each method under study. The remaining data were used to test the calibration against the standard method. Performance evaluation was based on Willmott’s index of agreement, confidence coefficient and root-mean-square error. When one meteorological variable was missing, either solar radiation, relative air humidity or wind speed, or in the simultaneous absence of wind speed and relative air humidity, the FAO-PM method showed the best performances and, therefore, was recommended for Jaíba. The FAO-PM method with two missing variables, one of them being solar radiation, showed intermediate performance. Methods that used only air temperature data are not recommended for the region.


Author(s):  
С. Н. Лебедев

Наводяться дані про залежність розвитку шкід-ливих поколінь ґронової листовійки на винограднихнасадженнях рівнинно-степового Криму від абіо-тичних чинників: середньодобової температуриповітря, суми опадів, відносної вологості повітря,а також площі листової поверхні куща винограду.На основі цих даних розроблені математичні мо-делі прогнозу розвитку фітофага, що дадуть змо-гу оптимізувати кратність і своєчасність захис-них заходів у боротьбі з зазначеним шкідником наконкретному сорті винограду. Provides information on the intent of the development ofmalicious generations Lobesia botrana of the leaf rolleron vine plantations of plain-steppe Crimea from abioticfactors: the average daily air temperature, amount of precipitation,relative air humidity, as well as the area of leafsurface bush of grapes. On the basis of these datadeveloped mathematical models of forecasting of thedevelopment of the phytophage, that allows to optimizethe frequency and timeliness of protective measures inthe fight against this pest on a particular cultivar ofgrapes.


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