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The Ministry of Agriculture Jihad in Iran implemented contract farming (CF) for wheat in 2021 to address marketing issues. This study compares agricultural sustainability for farmers participating in and not participating in CF. Agricultural sustainability was assessed by applying a combined index approach that considers economic, social, and environmental dimensions. The required data came from 620 wheat farmers in Golestan province, sampled using the multi-stage randomization technique. The data were evaluated using exploratory factor analysis (EFA) and clustering methods. The findings indicated a significant difference in the performance of economic and environmental sustainability dimensions between two groups of wheat farmers. For the participants, 14.2% were deemed unsustainable, 47.7% were considered partially sustainable, and 38.1% were classified as sustainable. For non-participants, the figures were 38.7%, 47.7%, and 13.5%, respectively. Therefore, it is suggested to provide more opportunities for participation in this program and expand it to other key crops. Additionally, authorities should provide more information about the benefits of the CF plan.

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Today, nanosilver is one of the most commercialized nanomaterials. The demand for synthesis of Nanosilver through biocompatible routs due to wide biomedical application has increased. Use of plants and plant products as sustainable and renewable resources in the synthesis of nanoparticles is more advantageous over other biological routes. In this study, biosynthesis of silver nanoparticles (AgNPs) using aqueous extract of Withania somnifera as reducing agent is reported. Effect of parameters such as AgNO3 concentration, aqueous extract, pH and formation time were investigated and optimized by UV-visible spectroscopy in the synthesis of nanoparticles. At room temperature, the solution color started to change from pale yellow to dark brown due to the reduction of silver ion. The transmission electron microscopy (TEM) was applied for size and morphological analysis of nanoparticles. TEM result shows a spherical structure with an average size ranging from 24-35 nm for silver nanoparticles.
 

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Poverty causes human distress, wandering of the mind and provision of sorrow. The leaders of UN member states were committed in the third millennium that the number of the poor should be reduced by half up to 2015. However, since there is a close relationship between the black economy and poverty in the Iranian economy, which has a growing trend, this shows the importance of identifying the factors effecting on the creation of black markets in urban areas on creating poverty. So the first step in designing and implementing new programs to reduce poverty is to review these offices. This study analyzes the effects of the black economy in rural and urban areas on poverty by using regression model (VAR). using this model, the variables of per capita income, unemployment, tax on income, direct tax burden, the degree of openness of the economy and inflation as the factors, which cause the black economy were studied for the years 1984-2007. The results showed that, in both the rural and urban areas, the per capita income variable has the most influence on poverty. This shows that if the policy makers want to improve and irradiate the poverty in urban or rural areas, correct changes in the per capita income variable with all accessories and institutional and distributation arrangements can be usefull.    

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Population growth and loss of environmental capacities for food production have rendered the realization of food security a more complicated task as compared to the previous decades. To cope with this crisis, sustainable agricultural development can play a remarkable role in improving food security. The present study aimed to explore the spatial effects of agricultural sustainability on food security of rural households in 30 provinces of Iran over the period of 2006-2016. For this purpose, first, the overall level of agricultural sustainability using a Composite Sustainable Agriculture Index (I_CSA) and weighting indicators were calculated based on Analytic Hierarchy Process (AHP) method. The Aggregate Household Food Security Index (AHFSI) was used to determine the food security of households in rural areas. Also, the effectiveness of agricultural sustainability on food security of rural families, as well as other effective factors, was examined using the mixed Spatial Autoregressive (SAR) model with panel data. Results show that the spatial spillovers of the agricultural sustainability influence food security positively and significantly. In fact, 1% increase in the agricultural sustainability index of a certain province directly improves food security of the same province by 0.043%, while its food security is indirectly enhanced by 0.0131% with 1% increase in the agricultural sustainability index of other provinces. It is imperative for policymakers of the agricultural sector to invest in production infrastructure of different provinces in Iran and focus on enhancing sustainable production as a prerequisite for the establishment of sustainable food security.
 

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Introduction:
Exchange rate pass-through (ERPT) is one of the most important indicators for monetary policymakers that shows the impact of exchange rate volatility on price indices (such as CPI, PPI, etc.). The economic stability and inflation environment are two factors affecting ERPT. The lower the inflation environment, the lesser the ERPT. In an oil-exporting country, the long-run situation of oil revenues can be a state variable of the economy and affect the expectations of economic agents. Therefore, the purpose of this study is to investigate the effect of sanctions against Iran and oil revenues situation on the ERPT from 1990Q2 to 2021Q1.

Methodology:
Regarding the implementing date of sanctions (2012Q1), the sanction period is from 2012Q1 to 2021Q1. Considering Lucas' critique, the switching models are not appropriate, and separated models are preferred. Therefore, by using the Bai-Perron (2003) method and taking oil revenues as a state variable of economy, the rest of the period is separated into two periods. The first period (from 1990Q1 to 2000Q4) is the phase of shortage in oil revenues and the second period (from 2001Q1 to 2011Q4) is the phase of abundance in oil revenues. The inflation environment during sanctions and shortage in oil revenues was high, and it was low in the period of abundance in oil revenues.
The ERPT for each period was calculated using the Structural Vector Autoregressive (SVAR) model. Oil price gap is the exogenous variable and the endogenous variables are respectively as follows: USA GDP, USA CPI, domestic GDP, exchange rate, liquidity and domestic CPI. All variables are in the first difference of logarithmic form. The Cholesky decomposition were used. The optimal lags for each model were selected by Hannan-Quinn information criterion (HQ), Akaike information criterion (AIC) and Final Prediction Error (FPE).
In this model, ERPT is the ratio of the accumulated response of CPI to exchange rate structural shock.
ERPT=k=1nDLCPIkk=1nDLEXk                                                                                             (1)
To investigate the effect of endogenous variables shocks on domestic CPI, variance and historical decomposition are used. Finally, the autoregressive trend of imports for each period is calculated to explain the status of imports versus different oil revenues. These equations can explain the dependency of CPI to imports.

Results and Discussion:
Only the ERPT in the sanctions period has a long-run effect on the economy. This effect is about 43%. The ERPT is 9.9% for the period of shortage in oil revenues, 25.1% for the period of abundance in oil revenues and 10.1% for the sanctions period. Unlike most previous studies, the results show that the lower the inflation environment, the higher the ERPT, and the higher the inflation environment, the lower the ERPT. The main cause of these unexpected changes in ERPT is related to share of imports in consumption basket. The import trend, either in the sanctions or the shortage oil revenues period, was decreasing while in the abundant oil revenues period, was increasing.
The results of the variance and historical decomposition show that in the period of sanctions, the exchange rate structural shocks have the largest share in inflation shocks, while in the other two periods, the inflation structural shock has the largest share in inflation shocks.

Conclusion:
The central bank of Iran is using the nominal exchange rate as an anchor to limit inflation and, finally, increase the monetary policymaker's credibility.  In Iran, increasing oil revenues leads to implementing the crawling peg exchange rate system instead of the managed floating exchange rate system, and consequently, not only the PPI inflation will be greater than the imported goods inflation, but also the imports will increasingly grow. Therefore, it is expected that the share of imports in the consumption basket grows and CPI will be more sensitive to imports. These results can explain the ERPT changes.
In order to increase the credibility of the monetary policy maker and reduce the ERPT sensitivity to oil revenue situations, instead of using the nominal exchange rate anchor, the central bank should be more independent, commit to implementing monetary policy. So, according to the real sector of the economy, the central bank should announce its goals in the short-run and commit to them and announce the status report at the appointed times, and in the medium run, the central bank should pursue only its goals implicitly and increase its credibility among economic agents by making the economy more predictable. The more independent the central bank is, the easier it will be to follow the above policy.
 

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The concept of anxiety occupies a crucial position in early Heidegger’s writings. Most prominently, it appears in Being and Time (1927) and “What is Metaphysics?” (1929) as a structurally central concept. After 1920s, Heidegger began to use the term much less frequently, leading some scholars to suggest a change in Heidegger’s view of the significance of the concept of anxiety. In this essay, we argue that central to the understanding of the role of anxiety in Heidegger’s thought is the fundamental difference between Heideggerian and psychological anxiety. This distinction is crucial as it is directly connected to the idea of the ontological difference, i.e., the difference between the ontical and the ontological, between beings and the Being of beings. Psychological descriptions of anxiety remain at the level of the ontical and, therefore, fall short of comprehending the ontological meaning of Heideggerian anxiety, which is one of Dasein’s basic possibilities of Being. Equipped with such an ontological understanding, we argue that the concept of anxiety remained central to Heidegger’s thought, early and late alike. We also suggest that Heidegger’s less frequent use of the term anxiety after “What Is Metaphysics?” could possibly be associated with his recognition that its terminological similarity with psychological anxiety may become a source of misunderstandings. Moreover, in the last section of the essay which functions as an addendum, we engage with Freud’s analysis of the uncanny and examine its relation to Heidegger’s Being-not-at-home. We argue that although Freud’s analysis of the uncanny does, in a sense, open up horizons beyond the reach of empirical psychology, his quasi-scientific quest for causal explanation ultimately remains within the framework of an ontical analysis.    

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Recently, in many fuel cell applications, foam is being used as a flow distributor to increase efficiency and achieve a more uniform distribution of reactants on the active surface. However, despite the improvement in the efficiency and performance of the fuel cell, this method does not fully achieve the desired uniformity in reactant distribution. Therefore, in this study, non-uniform porosity metal foam has been utilized to improve the homogeneous flow distribution on the cathode side of the PEM fuel cell. At first, the foam is assumed to be uniform with the same porosity. After the numerical solution of the flow in homogeneous foam (first type), Two types of foam with variable porosity coefficient have been designed. These foams are divided into checkerboard shape, where the porosity coefficients in the concave corners (dead areas) with low molar fraction of oxygen are higher. This facilitates easier movement of the flow towards these corners, resulting in a more uniform flow distribution. the simulation results indicate that, for a constant current density, the distribution of the mole fraction of oxygen in both types of foam with a variable porosity coefficient has become more uniform. Additionally, the average molar fraction of oxygen has increased by 9.45% in the second type of foam and by 32.02% in the third type of foam compared to the uniform foam, which indicates an increase in generated power. Also, compared to the uniform foam, the pressure gradient in the foam with variable porosity of the second type increased by 75.80%, while it remained relatively unchanged for the third type foam.

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During past years, economists have been endeavoring to determine both relationship and causality direction between real macroeconomic and nominal economic variables. In this regard, many studies have been carried out on the relation between money and inflation, resulting in the introduction of the notion of money neutrality which implies that permanent change of money supply just affects the nominal variables and has no lasting and real effect on production and employment. Furthermore, even when constant changes of money growth have no real impact whatsoever (except on real monetary equilibriums); money is stated to be super neutral in the long run. Although the majority of economists (with disparate schools of thought) concur with long-term money neutrality, there are still different opinions on the short-term and middle-term neutrality of the money. In following some major of them are presented. This paper investigates the existence of money neutrality in the Iranian economy applying Fisher and Seater approach during 1973 and 2014. The time series analysis, ARIMA model, is used to examine the problem and we consider various monetary aggregates, M1 and M2. Results show that we cannot reject the hypothesis test of money neutrality in Iran. Because all variables are non-stationary and integrated of order one I (1) we can only test the money neutrality. So it is strongly verified that money is neutral and it does not have any significant effects on real non-oil GDP in Iran. Also it was shown that the results are not sensitive to different aggregate money supply.