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The quality of urban spaces and the presence of residents are some of the primary issues of current urbanism, as the dominance of vehicles has diminished the commuting opportunity for different social groups and the liveliness of urban spaces. This is especially true for urban spaces where once acted as children’s playground and now have turned into vehicle routes, pushing their former function to the sides. In the dense landscape of district 10, with its insufficient open urban spaces, this issue is even more pronounced, doubling the need for creating urban spaces accommodating children. Tactical urbanism is a general term describing such urban interventions regarding different qualities (e.g. the scale of the project, provisional measures for reusing the unused potentials of cities, providing privileges and support, unofficial actions within legal bounds, or attention to and revitalizing abandoned spaces) and has been further extended in specific academic fields such as traffic engineering

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There are different ways in Russian language to express prohibition and caution. Choosing the suitable aspect of the verb (perfective or imperfective) in each of these structures shall be based on specific lexical and grammatical considerations that may change the semantics of sentences. Since the category of verbal aspect does not exist in Persian language (as in Russian), the Iranian students often find it hard to choose the right aspect of Russian verbs. This article attempts to provide a classification of different prohibitive and cautioning structures in Russian language and examine the role of verbal aspect in each of them in order to find the most appropriate lexical and grammatical structures that can express these semantics in Persian. The subject seems further promising due to this fact that some of these structures in both Russian and Persian languages do not use a negative imperative verb, rather they express the desired semantics through other syntactic methods.

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The imbalance in the development of regions across the country in various domains is one of the most pressing and challenging issues facing the nation today. This lack of balance and equity has led to certain areas enjoying greater access to both material and intangible resources, resulting in the significant polarization of the country’s spatial structure. This, in turn, has deepened class disparities and created severely underprivileged regions. Such unbalanced development has intensified the class divide between provinces and cities, prompting misguided migration to more developed areas and causing rural inhabitants to move to urban centers, which has further spurred the growth of informal settlements. The spatial and territorial imbalance in Iran is rooted less in natural inequalities and more in the decisions of policymakers over the course of history. Hence, the mindset of decision-makers cannot remain unaffected by the influential geopolitical contexts. This factor inevitably shapes the perspective of Iranian policymakers when it comes to locating activities and assigning uses to specific areas, often through the lens of a concept termed "security." Therefore, a fundamental question arises: What geopolitical factors underlie the security-oriented approach in spatial planning that has led to territorial imbalance within the country? And how have these factors been applied and institutionalized in organizing the country’s development framework?

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In this paper, a non - isothermal and two-phase flow in the cathode gas diffusion layer (GDL) of PEM fuel cell is modeled. To achieve more accurate boundary conditions, other components of fuel cell (membrane and anode GDL) are modeled. Governing equations including energy, mass and momentum conservation and auxiliary equations are solved by numerical method and the effect of gas mixture pressure in channels, relative humidity and effect of contact and mass exchange between two phases are investigated. Results show, it is necessary that both the contact and mass exchange between the gas and liquid phase to be considered. The performance curve and temperature distribution for single and two phase flow are compared for different amount of cathode channel humidity. The relative value of performance and temperature for single and two phase flow depends on the humidity of cathode channel. With increasing the cathode pressure from 0.5 to 5atm the value of water content in membrane and gas diffusion interface will increase about 20%. With increasing the water content in the membrane therefore the ohmic loss is reduced. With the reduction in the ohmic loss the temperature distribution along the fuel cell decreases but if the anode pressure increases the temperature distribution along the fuel cell increases. Keywords

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Ultrasound is used as a physical method to modify the functional properties of starch. In this study, the effect of ultrasound at 25, 45 and 65°C on the some rheological properties corn starch paste in the presence of Arabic gum was investigated. Results showed that the amylose leakage increased with increasing temperature; but in the presence of Arabic gum, amylose leakage decreased. Sonicated samples showed lower paste clarity. Clarity decreased with increasing temperature; but in the presence of gum arabic the clarity was increased. Clarity changes were lower in the presence of Arabic gum. The least gelling concentration (LGC) was higher in ultrasonic samples and also LGC was higher in the Arabic gum contained samples. Ultrasonication and Arabic gum reduced the maximum and final viscosity of starch paste. Sample sonicated at 45ºC was selected the best sample with minimum amylose content and showed the less changes clarity, higher LGC, minimum final viscosity. The presence of Arabic gum and the ultrasonic temperature are the important parameters that influenced the modification of starch properties.

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Nigella damascena and Nigella sativa are two important species of the genus Nigella that have many medicinal and industrial applications. Both species are widely cultivated in arid and semi-arid areas, and are affected by abiotic stresses, especially drought stress. In the present study, the effect of water deficit stress on seed yield, oil percentage and yield, total phenolics and flavonoids content, and antioxidant activity of both species were investigated during two growing seasons (2018 and 2019). In this experiment, different levels of irrigation (severe stress, mild stress, and control) and two species (N. sativa and N. damescena) were studied as the main plots and subplots, respectively. Seed and oil yields decreased sharply due to drought stress in both species. Means of the seed and oil yields in N. sativa were 540.65 and 206.92 kg ha^-1, respectively, and seed and oil yields in N. damascena were 286.37 and 100.29 kg ha^-1, respectively. Mild stress increased the oil content in both species, but severe stress significantly decreased the oil content in N. sativa. Linoleic acid had the highest percentage in both species, followed by oleic and palmitic acids, in the order of their appearance. Drought stress decreased polyunsaturated fatty acids (linolenic acid and linoleic acid), but saturated ones (stearic and palmitic acids) increased under drought stress with increasing drought stress, and the amount of phenolics and flavonoids in both species increased (P< 0.05). Furthermore, the IC₅₀ level decreased with increasing phenolics and flavonoids contents. In general, drought stress negatively affected seed and oil yields and edible oil quality in these species. Considering the acceptable seed and oil yields of N. damascena and its beneficial fatty acid compositions, it can be used in plant breeding programs and edible oil production.