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Showing 82 results for Cold


Volume 1, Issue 2 (9-2020)
Abstract

Nowadays, countries are required to develop the architectural plans by using vernacular and climatic architectures so that they can provide comfort to residents in addition to protect them from adverse climate factors such as wind, cold, and extreme heat. Vernacular architecture in both Nepal and Iran is seen as a precious model of climate adaptive design. The cold and mountainous climate of these two countries has created special conditions for residents. The purpose of current paper is to record the climatic design patterns of the two countries and to compare them in order to present new approaches derived from the vernacular architecture. From this point of view, this article provides a great help to researchers and designers in this field. Moreover, the present research is derived from library, documentary and statistical sources in an analytical and research method and finally, the conclusion is comparative to the promotional approach and to the practical goals. The results were obtained after collecting, recording, and adjusting the climate design patterns of the two countries. Finally, Nepal's vernacular architectural solutions, which were in line with vernacular and climatic architecture, were presented to guide the vernacular architecture of Iran for the benefit of residents. It is hoped that by using these solutions, we can take a step forward in protecting the environment and saving energy.

Volume 2, Issue 7 (12-2005)
Abstract

  Sugar cane juice contains soluble substance and solid suspension such as color compounds, polysaccharids, gums, proteins and etc that can effect on the quality and efficiency of the final product. Bentonit is a clay soil of montmorilonite and be used as a aid clarifier at industry. In order to make favourit clarification, is better that used type bentonit Na-calit for obtaining optimum point between surface sorption power and volum of sediment.After processing of target samples and obtaining of clarified juice with bentonit method brix, sucrose percent,purity, ash content, color and turbidity are comparced between clarified samples by bentonit method and cold liming method(Cold Defecation or calcium phosphate) as control samples until the best of requirement quantity bentonit and pH recognized. Purpose of this investigation is optimization of raw cane juice refining by bentonit.

Volume 3, Issue 2 (6-2014)
Abstract

Cold hardiness is one of the most common adaptations of insects at low temperatures. To understand the cold hardiness strategy of beet armyworm, Spodoptera exigua (Hübner), six temperature treatments were tested on the last instar larvae. Supercooling points of treatments were not significantly different. Two sugars, glucose and trehalose, as well as three polyols, myo-inositol, glycerol and sorbitol, were identified in these larvae. Trehalose was more affected in response to low temperatures in longer duration, and had a significant negative correlation with glycogen content. Despite the extensive sugar beet cultivation areas in Iran, beet armyworm population has been decreased in recent years. It seems that climate change regarding the global warming especially in autumn and winter could be a reason for decline in population outbreak of beet armyworm in the next generation. Based on findings of this study, it is suggested that overwintering larvae are freeze-intolerant insects but long term acclimation at sub-zero temperatures makes larvae tolerate presence of ice crystals in their body fluid.  

Volume 3, Issue 3 (9-2015)
Abstract

In the last decade, frequency of late cold incidence has increased in the upland forest nurseries. The aim of present study was to reduce the damage caused by spring frost and to increase the efficiency of Persian maple seedlings production in mountain nurseries. This study was conducted as split plot design with two main treatments and three replications in two consecutive years (2009-2010) in Farim Wood Company nursery, Mazandaran Province, Iran. Maple seeds were collected from a site located near the nursery. The main treatment was seedlings protection in two levels of covering the seedlings during the cold days and without covering. Sowing date was sub-treated and applied at six levels (2nd week of Dec., mid-Jan., 1st week of Feb., 3rd week of Feb., 3rd week of Mar. and mid-April).The results showed that seedling covered and seed sowing dates had significant (p<0.01) effect on reducing frost damage. Besides, interaction effect of sowing date and seedling cover was significant (p<0.01) in both years. There was no significant (p>0.05) effect between the sowing dates in protected plots. Overall, mortality of seedlings gradually reduced with shifting sowing date to March in uncovered plots. The maximum mortality rate was related to the sowing in 3rd week of February. Losses of seedlings were the same in covered and uncovered plots in mid-April sowing dates. In the unprotected plots, the maximum losses of seedlings were recorded in the sowing dates before March. In fact, if seed sowing of A. velutinum was postponed until early spring, the seedlings mortality rates were not significantly different in both treatments.

Volume 3, Issue 4 (12-2021)
Abstract

Détente as a policy seeks for decreasing tensions in foreign relations between states. Although there are lots of variables affecting the mentioned policy, this article basically concentrates on the role and status of military power in détente. The main argument is: there was a clear correlation between military power and détente in the Cold War era (especially between the U.S. and the Soviet Union as the two superpower) but in the post-Cold War era, we cannot see such a correlation between these variables, which means there has been substantial change in the correlation between military power and the détente policy. This research shows that, due to changes in the international system on the one hand, and an evolution in state attitudes towards the nature of power on the other, the role and status of military power has declined in the détente policy between states in the post-Cold War era.

Volume 5, Issue 3 (12-2016)
Abstract

The effect of cold-smoking was studied on the production of polycyclic aromatic hydrocarbons (PAHs), quality indexes, microbial community and omega-3 fatty acid profile of common carp. Thus, the fresh fish was smoked and stored for 30 days at 4°C. The nutritional values of both fresh and smoked products (protein, lipid, moisture and ash), pH and TVB-N indexes, microbial count including TC, molds and yeasts, were determined and polycyclic aromatic hydrocarbons PAHs, carcinogenic PAH4 compounds and also fatty acids composition were determined using HPLC and GC, respectively. The results showed that microbial community was well controlled and moisture content decreased during smoking, thus protein and lipid content were increased (P<0.05). TVB-N index for fresh fish was 10.87 and increased to 14.01 and 18.10 mg/100 in smoked and 30th days of production, respectively (P<0.05). High molecular weight of PAH4 were evaluated at 0.20, 1.70 and 1.30 µg/kg, respectively (P<0.05). No benzo[a]pyrene as a carcinogenic hydrocarbon in fresh fish was found, while it was found during smoking process (0.40 µg/kg) and after 30 days of storing (0.30 µg/kg) (P<0.05). The ω-3 fatty acids were determined in a range of 5.38 and raised to 5.53 g/100g in smoked fish and 5.47 g/100g after 30 days, which was insignificant (P>0.05).The results also showed that cold-smoking and one month storing at 4°C didn't change the composition of carp fatty acid, and useful series such as ω-3, ω-6, EPA and DHA were well preserved.

Volume 5, Issue 18 (10-2008)
Abstract

  The aim of this study was to demonstrate the inhibitory capacity of two strains of  gram positive bacilli, isolated from intestinal content of Persian sturgeon, against Listeria monocytogenes growth. Two strains Lactobacillus casei AP 8 and Lactobacillus plantarum A P 12 , were screened for their antilisterial activity against.  L. monocytogenes, using a disk diffusion agar test. However, L. casei AP 8 always had the highest inhibitory effect. The spoiling potential and antilisterial capacity of bacterial strains was tested in sterile cold smoked roach (CSR) blocks inoculated with 104 CFU g 1 of lactic bacteria and 102 CFU g-1 of Listeria monocytogenes and then stored for 10 days at 4 °C followed by 30 days at 20 °C. L. casei AP8 grew a little faster L. plantarum A P 12 and none of them showed any adverse effect on quality of the product ( i.e. no total volatile basic nitrogen (TVBN) production and no acidification. Lactobacillus casei AP8 was the most efficient strain, maintaining the level of L. monocytogenes at <50 CFU/ g  during  40 dayss of storage at 4 and 20°C. In conclusion, biopreservation of cold smoked roach using bacterial cultures such as L. casei AP8  is a promising way to inhibit the growth of pathogenic bacteria such as L. monocytogenes with low effect on the product quality.

Volume 6, Issue 3 (12-2017)
Abstract

To improve the texture and acceptance capabilities of silver carp burger and increase per capita consumption this product, the pectin was used as texture enhancers. Pectin is a polysaccharide that can be used in food to improve gel texture properties. In this research uses three different treatments, silver carp fried fish burger as control, fried fish burger with 0/3 % pectin as treatment 1, fried fish burger with 0/6 % pectin as treatment 2. Sensory evaluation and texture analysis tests was performed in zero phases and then monthly for six months and the results were compared with texture analysis. According to the results of the texture analysis of fish burger treatments, significant differences in the juiciness,overall acceptance was observed.The sensory evaluation index are also significant differences between fish burger formulated contains 0/3% pectin than the other two treatments was observed after six months storage at-18°C, therefor according to sensory evaluation and texture analysis, formulating fish burger contains 0/3% pectin most stable and acceptable formulation in terms of scoring during storage.

Volume 8, Issue 30 (7-2011)
Abstract

  The changes of mineral elements of the Abbot, Alison, Bruno, Monty and Hayward cultivars of kiwifruit (Actinidia deliciosa CV) were obtained from The Iran Research Center of Citrus (Tonekabon, North part of Iran) and were measured by ICP (Inductively Coupled Plasma) in the cold storage (at T= 0-4 0C, RH=75-85%) during 0, 9 and 18 weeks. Content of mineral elements (after harvesting) were in the ranges: Ca (42.726- 79.590), K (279.890-372.271), Mg (18.977-32.799), Na (1.444-2.5), Fe (0.290-0.521), P (31.296-42.221), Cu (0.037-0.207), Zn (0.162-0.308) and Mn (0.042-0.062 mg/100g fw). Statistical analysis showed that, potassium was the main mineral elements in the all studied cultivars and the Alison cultivar had the highest contents of mineral elements. In all cultivars of kiwi fruit the contents of mineral elements was significantly change during cold storage (P<0.01).

Volume 9, Issue 37 (12-2012)
Abstract

Thermal processing is the most common and traditional method to extend the shelf life of food. Because of negative effects of this processing method on sensory and nutritional properties of food, using of cold methods for sanitization has often been interesting substitutes for thermal treatment. High pressure, pulsed electric field, microfiltration, using of high pressure carbon dioxide and irradiation are such an important of the cold sanitization methods. High pressure processing inactivates microorganisms through deformation of their membrane, changing cell morphology, protein denaturation and inactivation of genetic mechanisms, disruption of ribosomes and denaturation of essential enzymes. Pulsed electric field treatment causes electroporation of the cell membrane wich results destruction of the microorganism. Microfiltration is based on the separation of microorganisms according to size differences with food components. High pressure carbon dioxide technique inactivates microorganisms through deformation of cell membrane, intercellular pH decrease, inactivation of essential enzymes, direct influence on metabolism, disordering of intracellular electrolyte balance, and removal of vital constituents from cell and cell membranes. Finally, irradiation inactivates microorganisms by causing some changes in biological systems. The benefits and defects of these mentioned methods have been investigated in this review paper and exhibited some examples for applications of each of them for sanitization of milk.

Volume 10, Issue 1 (10-2021)
Abstract

Rapid cold hardiness in response to sudden decline in air temperature plays an important role in the aphid survival. Rapid cold hardiness is a phenomenon that increases insect’s survival at sub-zero temperatures following a brief exposure to low temperatures above 0 °C. In this regard, the cabbage aphid Brevicoryne brassicae (L.) is able to increase its cold hardiness gradually during cold season and produce large population on host plants in Brassicaceae family. In this research, rapid cold hardiness of B. brassicae, and its effects on development time, longevity and fecundity were investigated. Direct transfer of aphids from 20 °C to a series of sub-zero temperatures for 2 h, resulted in a LT80 (estimated temperature required to kill 80% of tested population) of -7.3 °C. Preconditioning of first instar nymphs for 3 h and adults for 2 h at 0 °C resulted in the highest survival rates of 63% and 71%, respectively. Acclimation of aphids, by a cooling rate of 0.05 °C/min form 20 to 0 °C, prior the exposure to LT80 (-7.3 °C) resulted in the highest survival. No detrimental effects of rapid cold hardiness were observed on development time, longevity and fecundity. Results of the present study showed that rapid cold hardiness is induced in B. brassicae and increases the aphid survival in response to unexpected changes of temperature.

Volume 10, Issue 1 (10-2021)
Abstract

The Greenbug Schizaphis graminum (Rondani), one of the major pests of cereals, overwinter as adults and nymphs in temperate regions. The aphid population increases in early spring as the weather conditions become favorable, but it gradually decreases in mid-June as air temperature rises. Adult aphid colonies were acclimated to measure cold tolerance at 20, 15, 10, 5, and 0 °C for one week. In contrast, other colonies were acclimated to measure heat tolerance at 20, 25, and 30 °C for one week and 35 °C for two days. Then, the lowest temperature resulting in 50% mortality (LLT50) and the highest temperature resulting in 50% mortality (ULT50) of tested populations were defined. Moreover, changes of sugars and polyols were studied at the end of each thermal regime. The lowest LLT50 was -13.2 °C at 0 °C and the highest ULT50 was 40.1 °C at 35 °C. In the cold acclimation condition, glucose was the highest at 0 °C and reached to 80.9 µmol/g f.w. However, in the heat acclimation condition, the mannitol was the highest at 35 °C and reached to 43.7 µmol/g f.w. Findings indicate that high temperatures due to climate change could be a threat to aphid population size and distribution.
 

Volume 10, Issue 4 (12-2010)
Abstract

Abstract- Considering the diverse climates of Iran, the need for architectural design according to climate zones is obvious. Especially in critical thermal conditions this need will be more important and becomes the architect’s most important challenge. Cold climate is one of the important climates which deserve special design. In cold climate, summer is very short and environmental temperature is often below the comfort range, so the most important issue is heating. Since in most of the time we require to increase the temperature up to the comfort range. This article aims to provide solutions for critical climate conditions. So Tabriz with a dry and cold climate was selected and its thermal analysis was done. Through this analysis we find out when there is heating problems and we can design solutions based on these findings. This information will help us to design the selected site conditions.

Volume 10, Issue 38 (1-2013)
Abstract

Citrus disinfection has the major effect to prevent fungal attacks during storage. In this research, Thompson orange fruit was disinfected with ortho phenyl phenol solution by thermal fogging machine and then some of the samples coated by Carnuba wax. Physicochemical properties of orange samples (disinfected; disinfected-wax and control samples) were evaluated during three months storage. Factorial experiment design was selected to find the effect of coating and storage time on orange quality properties. The results showed that the effect of coating on all measured quality properties, and the effect of coating and storage time on pH values were significant (p<0.01). The amount of pH value of disinfected sample was significant (p<0.05) and was higher than the rest of the samples. So disinfection treatment enhanced fruit resistance against fungal attacks. Amount of total soluble solid and acid total of fruit juice for disinfected-wax samples decreased and increased during storage, respectively, which this trend could indicatefermentation phenomenon in the fruit. Therefore, disinfection with ortho phenyl phenol solution by thermal fogging machine was effective and preserved the fruit quality against fungal diseases during storage period.

Volume 11, Issue 1 (2-2025)
Abstract

Aims: Multiple sclerosis (MS) is a prevalent central nervous system (CNS) disorder characterized by inflammation and demyelination of nerves. The incidence of this disease has markedly risen in diverse regions, including the Middle East. Any factor that alters the quality and quantity of immune system components or influences the migration of immune cells toward the CNS may contribute to MS development. Evidence suggests that paragenetic, genetic, and environmental factors may be involved in increasing MS risk. This study aimed to investigate the effect of various infections on MS incidence.
 
Materials & Methods: This study included 475 MS patients and 260 healthy individuals from the Azeri population of East Azerbaijan province. Both groups filled out a questionnaire about their history of exposure to specific pathogens and infections before the age of 15.The relationship between a history of various infections and MS risk was examined.Findings: Mycoplasma pneumonia infection was significantly more prevalent in MS patients than in healthy individuals (p< .05). MS patients were more likely to suffer from common colds (p< .05), but no significant difference was observed regarding other infectious diseases (p> .05). Additionally, the prevalence of chronic infections was higher among MS patients (p< .05).
Conclusion: M.pneumoniae infection, common colds, and chronic infections were significantly more common in MS patients than in healthy controls. However, no significant association was found between other infectious diseases and MS risk. These findings emphasize the possible role of specific pathogens in MS development, warranting further investigation into underlying mechanisms and contributing factors.


Volume 11, Issue 3 (10-2022)
Abstract

Leopard moth, Zeuzera pyrina L. (Lepidoptera: Cossidae), is one of the important woodboring pests whose larvae bore into twigs, branches, and trunks of various woody species, weakening and sometimes killing trees or shrubs. Recently it has caused severe losses of walnut trees in Iran. This pest overwinters as different larval instars inside trees. Overwintering larvae were collected monthly from October 2020 to March 2021 from Maragheh walnut orchards, northwestern Iran, to determine the presence of cryoprotectants and their changes during autumn and winter. Overwintering larvae accumulated sorbitol, trehalose, and myo-inositol during winter. During cold months there was approximately 11 fold and 7.5-fold increase in trehalose and sorbitol contents, respectively. Glycogen content was the highest in October and decreased significantly with decreasing ambient temperature. Our results suggest that the accumulation of sorbitol, trehalose, and myo-inositol plays an important role in the harsh-season survival of Z. pyrina.
 

Volume 11, Issue 4 (9-2011)
Abstract

In this study, the potential of controlling engine cooling temperature has been investigated experimentally to reduce NOx emissions in heavy diesel engines. Experiments have been done on 90°C and 70°C cooling temperatures that lower temperature obtained via larger radiator and setting its thermostatic valve. Also, the effects of injection timing and the percentage cooled EGR simultaneously have been studied in order to trade-off NOx reduction and increasing other pollutants such as Soot, CO, HC and fuel economy. Experimental results which related to amount of pollutants and fuel consumption by altering the engine cooling temperature, injection timing, and the percentage of cold EGR shows that NOx emissions reduce 17% averagely also fuel consumption decreases negligible.

Volume 12, Issue 3 (11-2023)
Abstract

 The European grapevine moth, Lobesia botrana (Denis and Schiffermueller) (Lepidoptera: Tortricidae), is a significant pest causing economic damage to vineyards worldwide. In this research, the cold tolerance of the pupae and its relationship with diapause was investigated at 23 ± 0.5 °C, 70 ± 5% RH, and LD 12:12 h. One-day-old eggs were transferred to LD 12:12 h to induce diapause at the pupal stage. Diapausing pupae exhibited a mean supercooling point (SCP) of -24.35 °C, whereas in the non-diapausing pupae (23 ± 0.5 °C, 70 ± 5% RH, LD 16:8 h), it was -23.06 °C, with no significant difference between the two groups. Furthermore, diapausing pupae demonstrated significantly higher cold tolerance (LT50 of -14.43 °C) than non-diapausing pupae (LT50 of -3.33 °C). Diapausing pupae tolerated subzero temperatures without significant changes in the SCP, tolerating 11 °C lower than control pupae due to the short daylength alone. Our results suggest that the diapause state and cold hardiness of L. botrana are independent of changes after SCP, and the insect employs a freeze-intolerant strategy to overcome subzero temperatures. Cold acclimation at -5 and -10 °C for 72 h induced a significant decrease in the SCP of diapausing pupae, while a 72-h cold acclimation had no notable impact on the SCP of non-diapausing pupae. These findings provide valuable insights into the survival mechanisms of the European grapevine moth under cold conditions and diapause-related adaptations.


 

Volume 12, Issue 47 (7-2015)
Abstract

Mango is a tropical crop that has been originated from south east areas of Asia. Mango has high decayed nature because it climacteric property. In order to investigate the effect of Putrescine and cold water treatments on post-harvest quality  of mango, an experiment was done as factorial design in 2012. So local mango fruit was prepared at maturity stage, were treated with treatment combinations of Putrescine solution (0, 0.01, 0.1 mM) and cold distilled water (non-soaking and soaking for 30 and or 60 minutes). Quantitative and qualitative traits of fruit (like fresh and dry weight, length and width, firmness, total soluble solid, acidity, pH, taste and aroma, skin and pulp color) and also observation of rot symptoms have been measured. Results showed Putrescine and cold water treatments were affected fruit taste, acidity, and TSS/acidity ratio, also rot symptoms were reduced. Both concentrations of Putrescine affected the firmness and total soluble solids significantly. In all treatments combination of cold water and Putrescine fresh and dry weight was higher than control. The results indicated a positive and significant impact of mixed fruit dipping treatments in cold water and Putrescine in keeping appearance quality and improving storage life of mango fruit. Therefore the greatest concentration of Putrescine (0.1 mM) with immersion in cold water is recommended.  

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