هدف از این پژوهش بررسی اثر کیتوزان، تیمول و اتمسفر تغییر یافته بر ویژگی های فیزیکوشیمیایی، حسی و میکروبی خربزه تازه برش خورده بود. بدین منظور، برش های خربزه در محلول حاوی درصدهای مختلف کیتوزان (صفر، 1 و 2%) و تیمول (صفر، 25/0 و 5/0%) به مدت 2 دقیقه غوطه ور شدند. برش های تازه میوه پس از پوشش دهی و حذف محلول های اضافی و نمونه شاهد (پوشش داده نشده) در اتمسفر تغییریافته (10% دی اکسید کربن) و اتمسفر طبیعی بسته بندی و به مدت 8 روز در دمایC ͦͦ 4 نگهداری شدند. نتایج بیانگر افزایش میزان دی اکسید کربن و کاهش اکسیژن در بسته بندی تحت اتمسفر اصلاح شده و اتمسفر طبیعی همگام با افزایش دوره ماندگاری بود. اما در نمونه های پوشش دهی شده با کیتوزان و تیمول شدت کاهش اکسیژن و افزایش دی اکسیدکربن کمتر از نمونة شاهد بود. در پایان 8 روز نگهداری، افت وزنی در نمونه های پوشش دهی شده با کیتوزان و تیمول و نگهداری شده تحت اتمسفر تغییر یافته بسیار کمتراز نمونه شاهد بود (34/0% در مقایسه با 60/13%). افزایش غلظت کیتوزان و بسته بندی تحت اتمسفر تغییر یافته سبب افزایش حفظ میزان مواد جامد محلول، اسید قابل تیتراسیون، اسید اسکوربیک و سفتی بافت برش های خربزه شد، اما افزایش غلظت تیمول تاثیر معنی داری بر این ویژگی های کیفی نداشت. شاخص-های رنگی میزان سبزی- قرمزی (a*)، میزان آبی- زردی (b*)، میزان روشنایی (L*) و شاخص قهوه ای شدن (BI) نیز تحت تاثیر نوع بسته بندی و غلظت کیتوزان قرار گرفتند، اما، تیمار با تیمول بر شاخص های رنگی برش خربزه تاثیر معنی داری نداشت. اثر متقابل غلظت کیتوزان و غلظت اسانس نشان داد که برش های خربزه تیمار شده با غلظت 1% کیتوزان و غلظت های 25/0 و 5/0% تیمول دارای کمترین میزان بار میکروبی بودند. پوشش دهی با کیتوزان و تیمول و هم چنین نوع بسته بندی بر همه صفات حسی برش های خربزه (تاثیر معنی داری داشت (05/0 P<)؛ و ارزیابان در پذیرش کلی، غلظت 1%کیتوزان را بر غلظت 2% ترجیح دادند.

Saffron is considered as a valuable produce by producers and traders. Unfortunately, the use of its floral by products like petal which have proven to be antioxidant, antimicrobial and nutritional value is limited. In order to investigate the application of saffron petal extracts as an ameliorative on postharvest and processing quality of fresh-cut ‘Crimson Sweet’ watermelon, a completely randomized designed investigation was done on watermelon cubes with 1cm diameter (1±0.5 gram mean weight). Prepared watermelon cubes were divided into four groups and treated with saffron petal extract (10 % V/V) for 10 minutes, UV irradiation (maximum wavelength 253.4 nm and 15W) for 5 minutes, 10 minutes of saffron petal extract then UV irradiation for 5 minutes and control. After the application of treatments, fresh-cut watermelon cubes were stored at 5±0.5 ºC for 14 days. Sampling and observation of the studied characteristics (physiological loss in weight, soluble solid content, lycopene, microbial load and color quality (Chroma Hue)) was done every two days to find the trend of changes during the retention period. The results of experiment showed that petal extract of saffron could not decrease weight loss but it was significantly effective in lowering microbial load and increasing color quality, and prevention of lycopene degradation (P£5%). Although treatment of UV+SPE had better efficiency to suppress microbial load significantly (P£5%).

Introduction: there is a growing request for healthy fresh-cut products globally. However, due to the higher respiration of this kind of products and their suseptability to bacterial and fungal pathogenes, they spoil immediately after processing. These microbial activities usually cause a decrease in the quality and marketability of the product, including changes in its aroma, taste and appearance. The fresh-cut fruit and vegetable industry is one of the relatively new sectors and while the industry is growing, it is producing new products. Tissue rupture and cell rupture in these products leads to a decrease in their shelf life. On the other hand, these products need serious attention due to increased enzymatic activity, respiratory factors and microbiological considerations. In recent years, there has been growing evidence of consumption of minimally processed fruits and vegetable for the prevention of many chronic diseases. Some chemicals like chlorine, calcium chloride, etc., are used for sanitization purpose in fruit and vegetable industry, but these chemicals form carcinogenic chlorinated compounds, which have adverse human health impacts. Therefore, advanced alternative sanitization techniques, processing methods and improved packaging materials may be implemented for ensuring safety and extending the shelf life of fresh-cut fruit and vegetables. Application of edible coatings showed acceptable results on microbial load reduction and better preservation of processed products from the fruit to vegetables. Apple with proper nutritional value as a healthy snack have been considered in the diet of schools, public consumption and families. Finding a safe treatment to increase shelf life of freshly cut apples without harmful effets on environment and consumer is the main goal to this reaserch. Materials and Methods: In this study, the effect of fennel essential oil (Foeniculum vulgare L. ) with Aloe vera gel (in 3 levels of zero, 10 and 25 ml / l) and two magnetic field intensity (0 and 60 ml Tesla) in 3 replications during 7 days and in two storage temperatures (8 and 25 ° C) were observed. All treatments except the control were coated with Aloe vera gel. It was done in factorial format with a completely randomized design. In which traits such as color quality, SSC, pH, physiological weight loss, and browning rate were studied. Discussion and Conclusion: The results showed that the presence of the magnetic field in all samples treated with Aloe vera gel reduced the degradation, decrease oxidation and increase preservation of the appearance indices of apple slices. The presence of Aloe vera gel in all cases reduced water content reduction and weight loss. In the samples treated with different levels of fennel essential oil, fungal and bacterial growth was prevented, but in terms of appearance indices, it had a great decrease in quality and increased browning. No mold and fungal growth was observed in the samples at 8 and 25 ° C. Apparently, apples treated with 25 ml of essential oil lost their marketability. The use of Aloe vera treatment alone and without essential oil with a 60 ml Tesla magnetic field was found to be the best treatment. In general according to the results of this study, the application of fennel essential oil, which has antioxidant properties in lower concentrations, is useful to prevent the prevent fungal and bacterial growth, but is not suitable in terms of maintaining the appearance and reducing tissue destruction and causes faster and higher oxidation. Apple slices treated with high essential oil concentration became completely brown and lost their marketability even more than the control samples. Finally, it could be said that Aloe vera gel treatments in which a magnetic field was applied, in addition to water retention, had the best appearance and less oxidation. However, the use of Aloe vera gel and magnetic field to maintain the appearance is very useful and can be used in this industry.

Background and Objectives: Food packaging is one of the main applications of nanotechnology in the food section. Clay nanoparticles are among the nanoparticles used in food packaging. In this study, the effect of packaging film containing nano-clay particles on the characteristics of cucumber slices was investigated. Materials & Methods: The effect of nano-clay particles (0, 1 and 3%) and time (0, 3, 5, 7, 9 and 11 days) were studied in three replications in a completely randomized design. Cucumber slices were packaged in polypropylene (control samples) and polypropylene containing 1 and 3% nano-clay hydrophilic bentonite under modified atmosphere packaging. All samples were stored at 4 ± 1 ° C at a relative humidity (RH) of 90 ± 2 %. Microbial population was determined at 3-5 day intervals, and chemical properties, chlorophyll, texture, color were studied at 2-day intervals. Results: Control samples showed more loss of weight (p<0. 05) and higher L*, a* and b* during the storage (p<0. 01). Chlorophyll and firmness of the cucumber slices in the film containing 3% of nano-clay showed less decrease (p<0. 01). In addition, the application of modified atmosphere showed positive effect to preserve fruits and vegetables and packages containing clay nanoparticles significantly reduced the microbial population (p<0. 05). Conclusion: The packages containing clay nanoparticles under the modified atmosphere were more appropriate option than the control packaging in preserving the product.

Reduced Beam Section (RBS) connections are extensively used within seismic resistant steel moment frames in order to deal with the risk of brittle fractures in the connections, absorbing seismic energy through yielding and protect columns from damage. In this connection, at specific locations the beams flanges are trimmed back to provide weakened sections, in order to shift the plastic deformations away from beam-column connections and into the beam. Consequently, adequate ductility is provided by the frame to absorb the seismic energy and avoid the risk of brittle fractures occurring. The seismic performance of steel structures has been studied widely by many researchers. In general, the results of these studies indicate the good capability of RBS connections achieving these targets. In a reduced beam section (RBS) moment connection, in the region adjacent to the beam-to-column connection, a part of the beam flanges is trimmed selectively. Yielding and hinge formation are intended to take place primarily in the reduced section of the beam. Currently, in the design of RBS connections, the effect of RBS cutting parameters on the cyclic performance of the beam elements are not taken into account. However, using different RBS geometries for any beam with different sections can have different results in cyclic performance of the connections. In order to evaluate the effects of geometric parameters of RBS connection on the cyclic behavior of these connections, a parametric study is carried out on forty different European I-shaped steel cross-section specimens. These specimens are analyzed using ABAQUS finite element software under cyclic loading and the moment-rotation hysteresis curve was extracted for each of the specimens. In order to validate the FE model, a full-scale beam–column sub-assemblies were modelled in the general finite element (FE) software ABAQUS. An ideal curve was extracted from each of the hysteresis curves and using the curves, five parameters including Yield Moment (My), Peak Moment (Mc), Ultimate Rotation (θu), Ductility (μ) and Energy Dissipated Capacity (EDC) were extracted as the key design parameters for each sample. variation of the above-mentioned seismic design parameters in respect to the changes of RBS dimensions are analyzed. The results clearly illustrate that geometric features c do have most effect on the moment parameters. the parameters a and b have very little influence on moments which can be considered negligible, whereas these parameters have a small effect on the ultimate rotation, ductility and energy dissipated capacity. Increasing the value of c between its lower and upper limits, reduces the My more than 20% and Mc more than 17%. The effect of the distance of the cut area from the column face (a) and the length of the cut area (b) on the moment is close to zero and can be ignored. The effect of a and b on the ultimate rotation, ductility and energy dissipated capacity is less than five percent. However, the parameter c has significant influence over all the five seismic design parameters considered. Investigating the graphs of the variation of the key seismic design parameters respect to the changes of RBS dimensions shows that there is not enough correlation between the RBS parameters and the key seismic design parameters to propose a single equation between the key seismic design parameters and RBS parameters. Investigating the relationship between RBS dimensions, moment of inertia of RBS and full section characteristics showed that a relationship can be established between these parameters and the key seismic design parameters. At the end, the results of the investigation and relationships for calculating the key seismic design parameters were presented. This relationship was presented as a single equation, which includes the effect of all the above parameters. Using the obtained equation, the value of each of the key seismic design parameters can be calculated based on the dimensions and geometric characteristics of the section and the beam cutting dimensions.

Parsi zira (Buniumpersicum Boiss.) that is also called mountainous or black zira, is one of the most important medicinal plants with high economic importance. There is a little infonnation about in vitro culture of Parsi zira. Fragmented embryo was used as an explants in Bunium persicum regeneration. In this method, a great callus induction and regeneration occurred only on the same medium without any subculture. In this research, MS media containing different concentrations of plant growth regulators, NAA and 2,4-D alone or together with Kin, were used. The experiment was conducted using completely randomized design with 30 treatments and 10 replications per treatment. The treatment containing 0.1mg-1 NAA and 2mgl-1 Kin was the best one for regeneration. The treatment containing 0.1mg-1 NAA and 0.5mg-1 Kin was the best one for somatic embryogenesis. Regeneration occurred in some treatments without kinetin, showing that kinetin is not essential for Buniumpersicum regeneration.

The Asmari carbonate formation in Lorestan is seen in the form of a medium to the thick limestone-rich layer of benthic foraminifera and often as a rock formation. In this study, the stratigraphic sequence of Asmari carbonate formation in the Chenareh Anticline section located in the south of Lorestan basin and Amiran Anticline section located in the middle part of Lorestan basin were studied in terms of lithology and micro biostratigraphy. The thickness of the Chenareh Section was 180 meters and the Section of Amiran Anticline was 158 meters. In total, more than 290 thin sections of both were prepared and examined in the laboratory. The results of fossil studies based on the expansion of foraminifera finally lead to the introduction and presentation of 1 Assemblage biozone in the Amiran anticline section and 3 Assemblage biozones related to the Chenareh anticline stratigraphic section. Accordingly, the age of the Asmari Formation is in the Chenareh section is Oligo-Miocene (Chattian-Bordigalian) and in the Amiran section is Miocene (Bordigalin). According to the lithostratigraphic studies, the border of the Asmari Formation in both sections of Chenareh and Amiran with Shabazan Formation is progressive-continuous and discontinuous, and in both sections of the upper boundary with Gachsaran Formation can be seen in the same way as evaporative sediments.

A λZAP library of B. cereus 569 UM20.1 chromosomal DNA was constructed and screened for the desired clone. Chromosomal DNA from the above strain was extracted and partially digested with Sau3A restriction enzyme. DNA fragments with 4-9 kb size were cut out of the agarose gel and purified. The DNA was then cloned into BamHI digested Lambda arms and the reaction was packaged. In order to determine the concentration of infective phage particles and the proportion containing insert DNA, the packaged extract was titered and a recovery of 2.8×105 pfu.µg-1 of vector was obtained. In vivo excision of the pBK-CMV plasmid from the λZAP express vector was carried out and resulted in isolation of two plasmids,pJB1 and pJB2. The two plasmids were used for DNA sequence analysis.