Leaf tissue extract from Artemisia siebery, A. AUCHARY and A. scoparia were evaluated for their allelopathic effects on seed germination and seedling growth of Amaranthus retroflexus. The experiment was arranged in a completely randomized layout with three replications. The treatments were three species of Artemisia, and nine levels of leaf extracts (0, 6250, 10000, 12500, 20000, 40000, 80000, 125000 and 162500 ppm). Results showed that Amaranthus seed germination, root and shoot length were reduced by Artemisia species extracts. A. AUCHARY had more effect on Amaranthus seed germination. Estimated reduction of Amaranthus seed germination by 80000 ppm extract was 36.1, 86.3 and 82.5 % for A. scoparia, A. AUCHARY and A. siebery, respectively. The maximum inhibitory effects on root and shoot length was observed by A. AUCHARY. The estimated rates of A. AUCHARY extract required for a 50% reduction in Amaranthus root and shoot length were, 19520 and 21960 ppm, respectively.  

Reducing environmental and economic costs of crop protection is a major concern. In this context, a revived interest in studying allelopathic factors has been noted. In this study, leaf tissue extract from Artemisia siebery, A. AUCHARY and A. scoparia were evaluated for their effects on seed germination and seedling growth of Avena ludoviciana. Dried leaf tissue was extracted by methylene chloride. The experiment was arranged in a completely randomized layout with three replication. The treatments were three species of Artemisia, and nine levels of leaf extracts (0, 6250, 10000, 12500, 20000,40000,80000, 125000 and 162500 ppm). Results showed Avena seed germination, root and shoot length were reduced by Artemisia species extracts. A. AUCHARY had more effect on Avena seed germination. A. scoparia not had effect on Avena seed germination and estimated reduction of Avena seed germination by 80000 ppm extract was 48 and 44.7 % for A. AUCHARY and A. siebery, respectively. The maximum inhibitory effects on root and shoot length was observed by A. AUCHARY. The estimated rates of A. AUCHARY extract required for a 50%reduction in Avena root and shoot length were 6640 and 9970 ppm, respectively.

Sound is one of the forms of mechanical energy and the two main characteristics of sound are intensity or power and frequency or wavelength of sound.their performance against the incoming sound wave, industrial silencers can be divided into two general groups of resonating and absorption silencers, the main difference between these silencers is the release of sound energy from the channeling system, which is one of the common examples of the use of resonating type silencers, their use in It is the internal combustion engines that distinguish absorption silencers from the resonator type based on the fact that the main and visible part of the act of muting the sound is achieved by changing sound energy to heat energy.The goal of this article is to design a muffler based on the breaking of sound frequencies resulting from the movement of fluid in the exhaust output of vehicles, which leads to a reduction of at least 50 db of sound and gives the operator enough peace and concentration. In this article, after examining three types of mufflers, absorbent mufflers that use the properties of porous absorbent material to absorb passing sound and are the simplest form of mufflers, have been selected, analyzed and reviewed and are suitable for the OM457 engine of Idem Industrial Company. It designed for maximum inlet exhaust temperature is 520 and for the maximum kW power is 315 with the maximum discharge relative pressure of 185 mbar for homogenization with the standard atmosphere.

Camelina (Camelina sativa), an oilseed plant in the Brassicaceae family, is recognized as a significant crop both biologically and industrially, with recent attention shifting towards its potential as a biofuel source. The close genetic resemblance between Arabidopsis thaliana and C. sativa has sparked interest among researchers in manipulating oleic acid levels through microRNAs and the gene sequences FAE1-A and FAD2-A. A recent bioinformatics study focused on these genes in camelina revealed that the FAE1-A protein is hydrophobic, while FAD2-A is hydrophilic. Structural analysis indicated GMQE values of 0.88% for FAE1-A and 0.93% for FAD2-A. The FAE1-A protein’s secondary structure comprises 49% helix, 11% beta-sheet, 41% coil, and 9% membrane content with a confidence level of 79.2%. Similarly, the secondary structure of the FAD2-A consists of 43% helix, 12% beta-sheet, 45% coil, and 30% membrane content with a confidence level of 79.8%. Codon preference patterns were explored using the Sequence Manipulation Suite database to understand the relationship between codons and gene performance. Furthermore, analysis of FAE1-A and FAD2-A gene expression showed peak expression levels in developing seeds approximately 20 days after pollination. Further investigation into these structures promises to enhance our understanding of fat biosynthesis, thereby improving oil quality in C. sativa.

Purpose: Resilience in start-ups is a challenging issue that has caught the attention of policymakers and business owners. The present study is an attempt to provide a model for designing the resilience model of start-up businesses as a path to the future of start-up businesses. Method: This research is practical in terms of purpose and from the perspective of data collection is a qualitative research that has been done by content analysis method. The data collection method is semi-structured interview. Interviews with participants continued until they reached the theoretical saturation point, which was achieved by conducting 15 interviews. Participants were selected by snowball and purposeful method and data analysis was done through three coding steps (open, axial, selective) with MAXQDA2020 software. Findings: Based on the research results, the components of "cognitive resilience, financial resilience, adaptive resilience" as well as the effective organizational factors of "precedent, drivers and boys and resilience consequences" were identified. In this research, foresight and futures studies were identified as the drivers of resilience of start-up businesses. Conclusion: Resilience enables businesses to respond effectively to the dynamic conditions of their environment and maximize their competencies through strategic foresight and as a result gain more value than their competitors in the field of business. In this regard, the integration of foresight in the process of business resilience can be suggested as a facilitator of drivers.

In this paper, a new high step-up current-fed LLC resonant DC-DC converter with a center-tapped transformer is proposed. By selecting the switching frequency to be lower than, but near to, the series resonant frequency of the LLC resonant tank, soft-switching operation of all semiconductors, i.e., zero voltage switching (ZVS) turn-on of power MOSFETs and zero current switching (ZCS) turn-off of diodes is achieved. This leads to lower electromagnetic interference (EMI) and lower switching losses and improves the converter efficiency. An interleaved structure is used at the primary side. Thus, input current ripple is smaller, and its frequency is twice the switching frequency. Consequently, a smaller input filter is necessary in practice. The converter with 1.2 kW output power and 760 V regulated output voltage with 80-200 V input voltage variations is simulated. The output voltage is regulated by using asymmetric pulse width modulation (APWM) at 200 kHz switching frequency. Finally, a 700-W prototype has been implemented and experimental results are also presented to verify the simulation results.

Introduction: Gestational diabetes mellitus is the most common medical complication during pregnancy that negatively affects the health of mother and fetus and neonate. Gestational diabetes mellitus occurs in 3-5% of pregnancies. Early detection of gestational diabetes can prevent of these complications. This study was performed with aim to determine the association between pregnancy-associated plasma protein A (PAPP-A) and gestational diabetes to detect a risk factor for predicting gestational diabetes.Methods: This prospective analytical study was performed on 250 pregnant women referring to six healthcare centers of Qazvin from February to October 2016. PAPP-A was measured at 11-14 gestational weeks, then 75 gr glucose tolerance test was performed on the samples at 24-27 gestational weeks. The association between gestational diabetes and PAPP-A was studied. Data were analyzed by SPSS software (version 21) and Chi-square, t-test, Mann-Whitney, relative risk, and logistic regression. P<0.05 was considered significant.Results: Twenty-four subjects (30.8%) of patients with decreased PAPPA and 15 (8.7%) of patients with normal PAPP-A were diagnosed with gestational diabetes. Chi-square test showed significant difference between two groups based in terms of gestational diabetes (P<0.001). The risk of gestational diabetes in the patients with decreased PAPP-A was 3.90 times more than control group (CI=1.87-8.14, P<0.001).Conclusion: Low level of PAPP-A at gestation weeks of 11-14 can be a possible risk factor for the incidence of gestational diabetes. Therefore, it can be used as an early detection test for preventing the fetal and maternal adverse effects.