n. ebrahimi

Chemical fertilizers have a devastating impact on soil and the environment when used in seedling production and planting. Conversely, biofertilizers can enhance soil structure and fertility while mitigating the harmful effects of chemical fertilizers on the environment. This study aimed to identify an appropriate biofertilizer for Zygophyllum eurypterum, a species that is particularly amenable to arid area restoration. To this end, we conducted an experiments using six different biofertilizer treatments (Azotobacter chroococcum, Azospirillum lipoferum, Flavobacterium F-40, Bacillus megaterium, Pseudomonas fluorescens, and Rhizophagus irregularis) and fertilizer-free control in a completely randomized design by cultivation of the plants in the seedling bags with 15 replications. This was done in the spring of 2018, in the research farm of Semnan University. Vegetative growth parameters such as root length, fresh and dry weight of roots and shoots, number of leaves, shoot diameter, and total chlorophyll were measured three months after planting. The percentage of root colonization with mycorrhizal fungi was measured at three and six months of age of seedlings. In this context, the maximum length of root (33.40 cm) and shoot (18.20 cm), height (51.30 cm), weight of root (99.94 g) and shoot (473.90 g), number of leaves (58.00), shoot diameter (3.32 mm) and total chlorophyll (74.96) were observed in the treatment by Pseudomonas fluorescens. Symbiotic mycorrhizal fungi was confirmed and it increased root length and plant height. The percentage of root colonization increased over time. Root to shoot ratio was increased by application of Azospirillum lipoferum fertilizer. The results showed that the use of biofertilizers Pseudomonas fluorescens, Azospirillum lipoferum, and Rhizophagus irregularis can be recommended in the production of Zygophyllum eurypterum seedlings.

Entrepreneurship with innovation in organizational structure and business methods has had tremendous results in economic, social improvement of organizations and the whole society. Ethics is undoubtedly a framework through which entrepreneurship creates values ​​related to the real needs of society and pursues long-term growth and development. The purpose of this article is to examine the relationship between entrepreneurial supply chain management and organizational performance with regard to the role of ethics.

This study was applied and descriptive-correlational. The statistical population of the study consisted of industrial companies in Gorgan city, from which a sample of 198 manufacturing companies was selected by simple random sampling. The research instrument was 6 standard questionnaires and the data were analyzed using Structural Equation Test with partial least squares approach in Smart-PLS software.

The results of data analysis showed that there is a significant positive relationship between supply chain business intelligence with increasing level of organization integrity and supply chain integration. There is a significant relationship between supply chain management with increasing level of organization integration and supply chain integration. There is a significant positive relationship between increasing level of organization integration with supply chain integration and ethical performance of organizational resources. On the other hand, there is a significant positive relationship between supply chain integration and organizational resource-oriented ethical performance and there is a positive significant relationship between ethical-oriented organizational resource performance and buyer financial performance.   

Based on the results of the present study, it can be said that entrepreneurial supply management that focuses on the ethical performance of the organization will lead to an increase in the level of organizational integrity and the success of supply management goals. Because supply chain integrity depends on the ethical performance of the enterprise resource-based ethics. The results of this study will help supply managers improve their performance by changing the culture and process of supply chain management toward entrepreneurial orientation and ethics.

There are several attempts to improve surface characteristics of biomaterials with thick film coatings. In this research, a class of protective coating layers of bi-layered Hydroxyapatite (HA)/Al2O3-SiO2 (with 10, 20, 30 %wt SiO2) were deposited on titanium (Ti) surfaces by plasma spray technique. The surface features of the applied coating layers were evaluated in detail to confirm the effectiveness of the technique for further biomedical applications. The results demonstrated that uniform and bi-layered plasma sprayed coatings can be successfully prepared through the optimization of engineering parameters. Also, it was found that the roughness of the bi-layered coatings increases with increasing the number of coating layers. The corrosion behavior of the coated and uncoated samples was comparatively investigated using electrochemical tests. The measured current densities (icorr) for HA, (HA)/Al2O3-SiO2 (with 10, 20, 30 %wt SiO2) were 0.27μA/cm2, 0.28 μA/cm2, 0.23 μA/cm2, 0.79 μA/cm2, respectively. According to the results, corrosion resistance of samples with 20% SiO2 is significantly improved compared to the single-layer HA and bare Ti. The outcomes of FESEM results revealed that porosity and cavities related to evaporation of adhesive PVA and it is confirmed by increasing the percentage of silica to more than 20%, porosity has increased. In conclusion, the proposed coating system showed promising abilities for future biomedical applications. It could be optimized and improved by changing the structural characteristics of the substrate, chemical composition and porosity of the coating layers.

Nitrogen (N) loss from the agricultural lands is one of the most important point-source of N which pollutes natural aquifers. While N is one of the driving nutrition in fulfilling crop growth cycle, unmanaged fertilization beyond crop demand leads to increased N leaching to groundwater resources and causes environmental unsustainability. This issue is more highlighted in rainfed cultivation due to unexpected rainfall events which might be beyond crop water requirement. Hence, we determined optimal N fertilizer rate under rainfed maize cultivation in Mazandaran province. In this regard, HYDRUS-2Dwas first calibrated and validated for soil hydraulic and chemical parameters based on data collected during a two-year maize field investigation. The model was then used for simulating the amount of nitrate leaching, N uptake and N residual in soil under 9 fertilization levels treatments including no fertilization (only 10 kg ha-1 was considered as initial soil N nitrogen), 50, 100, 150, 200, 250, 300, 350 and 400 kg ha-1. Finally, optimal fertilization rate for rainfed maize was determined based on N use efficiency and the ratio of crop yield to N fertilization rate.While according to RMSE (0.8-1.18 mm for water content, 0.38-7.95 mg l-1 for nitrate concentration, and 3.96-8.96 kg ha-1 for crop N uptake),HYDRUS-2D was capable enough for simulating soil water and solute dynamics, the lower variation in soil water content and solute concentration during the cropping cycle caused the model to be more accurate for simulating soil water and solute dynamics in these layers compared to the surface layer.Based on the simulated results, N uptake will increased by 20 kg ha-1 on average in response to every 50 kg ha-1 increase in N fertilization rate beyond 200 kg ha-1. N leaching below different soil depths increased along with reduced crop N uptake, which led to nutrient removal from the surface soil layers and its aggregation in underlying soil layers at the end of the growing season. Fertilizer use efficiency had its highest value at fertilization rate of 150 kg ha-1, while it remained unchanged at higher N rates. Nevertheless, increased N rate always lead to yield reduction per unit applied fertilizer.

Self-weighting estimation through equal probability selection methods (epsem) is desirable for variance efficiency. Traditionally, the epsem property for (one phase) two stage designs for estimating population-level parameters is realized by using each primary sampling unit (PSU) population count as the measure of size for PSU selection along with equal sample size allocation per PSU under simple random sampling (SRS) of elementary units. However, when self-weighting estimates are desired for parameters corresponding to multiple domains under a pre-specified sample allocation to domains, Folsom, Potter and Williams (1987) showed that a composite measure of size can be used to select PSUs to obtain epsem designs when besides domain-level PSU counts (i.e., distribution of domain population over PSUs), frame-level domain identifiers for elementary units are also assumed to be available. The term depsem-A will be used to denote such (one phase) two stage designs to obtain domain-level epsem estimation. Folsom et al. also considered two phase two stage designs when domain-level PSU counts are unknown, but whole PSU counts are known. For these designs (to be termed depsem-B) with PSUs selected proportional to the usual size measure (i.e., the total PSU count) at the first stage, all elementary units within each selected PSU are first screened for classification into domains in the first phase of data collection before SRS selection at the second stage. Domain-stratified samples are then selected within PSUs with suitably chosen domain sampling rates such that the desired domain sample sizes are achieved and the resulting design is self-weighting. In this paper, we first present a simple justification of composite measures of size for the depsem-A design and of the domain sampling rates for the depsem-B design. Then, for depsem-A and -B designs, we propose generalizations, first to cases where frame-level domain identifiers for elementary units are not available and domain-level PSU counts are only approximately known from alternative sources, and second to cases where PSU size measures are pre-specified based on other practical and desirable considerations of over- and under-sampling of certain domains. We also present a further generalization in the presence of subsampling of elementary units and nonresponse within selected PSUs at the first phase before selecting phase two elementary units from domains within each selected PSU. This final generalization of depsem-B is illustrated for an area sample of housing units.

The influence of salinity on the different polyamine fractions (free, conjugated, and bound) was compared in a natrophilic halophyte (Beta vulgaris L. cv. IC) and a salt sensitive glycophyte (Nicotiana rustica L. cv. Basmas). Low-level salinity (25 mM NaCl) and high salinity (150 and 50 mM NaCl for sugar beet and tobacco, respectively) were supplied in hydroponics. Under low salinity shoot dry weight increased in sugar beet, but decreased in tobacco. Under high salinity growth reduction in sugar beet and tobacco were similar. However, sugar beet accumulated higher Na and Cl in roots and shoots than tobacco. Low salinity caused an increase (22%) in the rate of net CO2 assimilation in sugar beet. This parameter was depressed in both species under high salinity. Sugar beet had constitutively higher free spermine levels in roots and shoots than tobacco. Spermidine levels were constitutively higher in shoots of sugar beet and in roots of tobacco. Under salt stress tobacco plants tended to increase free polyamine levels. The most important salt–induced rise in polyamine titer, however, was found in roots and shoots of sugar beet. In sugar beet roots the bound putrescine fraction increased 9.3-fold under growth- stimulating salt supply (25mM) and 20-fold under salt stress (150 mM). In tobacco roots this fraction only increased 2.3 and 3.8-fold under mild (25 mM) and high salt stress (50 mM), respectively. Our results provide support to the view that bound putrescine contributes to the protection against salt stress in the natrophilic sugar beet.