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Carotenoid metabolism in Plants： The Role ol Plastids

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molecular Plant 2018年第1期11卷 58-74页

作者： Tianhu Sun Hui Yuan Hongbo Cao mohammad yazdani Yaakov Tadmor Li Li Robert W. Holley Center for Agriculture and Health USDA-ARS Cornell University Ithaca NY 14853 USA plant Breeding and genetics Section School of Integrative Plant Science Cornell University Ithaca NY 14853 USA College of Horticulture Hebei Agricultural University Baoding Hebei 071001 China Plant Science Institute Israeli Agricultural Research Organization Newe Yaar Research Center P.O. Box 1021 Ramat Yishai 30095 Israel

Carotenoids are indispensable to plants and critical in human diets. Plastids are the organelles for carotenoid biosynthesis and storage in plant cells. They exist in various types, which include proplastids, etioplasts, chloroplasts, amyloplasts, and chromoplasts. These plastids have dramatic differences in their capacity to synthesize and sequester carotenoids. Clearly, plastids play a central role in governing carotenogenic activity, carotenoid stability, and pigment diversity. Understanding of carotenoid metabolism and accumulation in various plastids expands our view on the multifaceted regulation of carotenogenesis and facilitates our efforts toward developing nutrient-enriched food crops. In this review, we provide a comprehensive overview of the impact of various types of plastids on carotenoid biosynthesis and accumulation, and discuss recent advances in our understanding of the regulatory control of carotenogenesis and metabolic engineering of carotenoids in light of plastid types in plants.

关键词： carotenoid plastid regulation metabolism metabolic engineering

Short circuit analysis of a fault-tolerant current-limiting high temperature superconducting transformer in a power system in presence of distributed generations

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Superconductivity 2024年第1期9卷 74-86页

作者： Alireza Sadeghi Shahin Alipour Bonab Wenjuan Song mohammad yazdani-Asrami Propulsion Electrification&Superconductivity GroupAutonomous Systems&Connectivity DivisionJames Watt School of EngineeringUniversity of GlasgowGlasgow G128QQUnited Kingdom

Power transformers are key elements for the safe and reliable delivery of electrical energy generated by renewable energy resources to consumers via transmission ***‐tolerant current‐limiting High Temperature Superconducting(FTCL HTS)transformers are type of superconducting transformers that tolerate fault for seconds and limit the fault current without the threat of burnout or delamination of tapes and deformation of *** this paper,the fault performance of a FTCL HTS transformer in a standard IEEE power system is *** studied transformer is a 50 mVA 132 kV/13.8 kV transformer where both windings are made up of HTS *** understudied power system consists of two microgrids with distributed *** of the power in microgrids is supplied by the upstream grid which is connected to the microgrids through the HTS *** fault scenarios have been considered in this power system,in each one of these scenarios,a fault happens in one of the *** considered fault scenarios have an approximate fault current of 18x to 23x of the rated current in the secondary *** showed that insulated windings in FTCL HTS transformers could substantially reduce the peak temperature of the HTS windings,compared to bare ***,post‐fault loading is imposed on the HTS windings,to observe their performance against the current increase after fault *** this case,for the first scenario of the faults,the FTCL HTS transformer could tolerate 192%of post‐fault overloading,while this number for the second fault scenario is 170%.Finally,the impact of post‐fault loading on the full recovery time was discussed.

关键词： Fault Energy Heat dissipation Heat transfer Insulation Recovery Time Temperature rise

Arctic sea-ice extent: No record minimum in 2023 or recent years

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 52-55页

作者： Ola m.Johannessen Tor I.Olaussen Nansen Scientific Society BergenNorway Nansen Environmental and Remote Sensing Center BergenNorway

Arctic sea-ice extent reaches its minimum each year in September. On 11 September 2023 the minimum was 4.969 million square kilometers(***^(2)). This was not a record low, which occurred in 2012, when the minimum was 4.175 ***^(2), 0.794 ***^(2) less than the minimum in 2023. However, the ice extent had decreased by 0.432 ***^(2) compared with 2022. Nevertheless, the summer melting in 2023 was remarkably less than expected when considering the strong heat waves in the atmosphere and ocean, with record temperatures set around the world. In general, there is a high correlation between the long-term decrease in sea-ice extent and the increasing CO_(2) in the atmosphere, where the increase of CO_(2) in recent decades explains about 80% of the decrease in sea ice in September, while the remainder is caused by natural variability.

关键词： Sea ice Arctic minimum ice Climate

A new model to predict roadheader performance using rock mass properties

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Journal of Coal Science & Engineering(China) 2013年第1期19卷 51-56页

作者： yazdani-Chamzini ABDOLREZA SIAmAK Haji Yakhchali Young Researchers Club South Tehran Branch Islamic Azad University Tehran 14115/344 Iran Department of Industrial Engineering College of Engineering University of Tehran Tehran 11365/7117 Iran

Prediction of roadheader performance plays a significant role in the plan of tunnel construction, which is influenced by different key parameters, including rock strength, discontinuity in rock mass, type and specifications of roadheader machine, and brittleness. The main aim of this study is to build a robust empirical equation based on rock mass properties for the roadheader performance prediction. For achieving the aim, a dataset composed of roadheader performance rate and rock properties is established using the dataset compiled from an underground coal mine located in a remote rugged desert environment some 85 km south of Tabas City in mid east Iran. By using gathered data, the statistical analyses are conducted between rock mass properties and roadheader performance to find whether there is a significant relationship between input variables and roadheader performance. The results show that rock mass properties have a considerable impact on the rate of the roadheader performance. It is demonstrated that the proposed model can accurately predict the roadheader performance as a function of rock mass properties.

关键词： roadheader performance Tabas Coal mine rock mass property alpha angle prediction

Shear behavior and dilatancy of an artificial hard-matrix bimrock: An experimental study focusing on the role of blocky structure

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Rock Mechanics Bulletin

Rock mechanics Bulletin 2024年第4期3卷 83-101页

作者： Amir yazdani Saeed Karimi-Nasab Hossein Jalalifar Department of mining Engineering Isfahan University of TechnologyIsfahanIran Department of mining Engineering Shahid Bahonar University of KermanKermanIran Department of Petroleum Engineering Shahid Bahonar University of KermanKermanIran

Bimrocks are characterized by their geotechnically significant blocky structure,presenting complex shear *** study investigates the shear behavior and dilatancy of bimrocks featuring a rock-like matrix,such as *** study addresses a gap in current research,which has predominantly examined the shear behavior of soil-matrix bimrocks(bimsoils).Laboratory direct shear tests were performed on idealized models with varying volumetric block proportions(VBPs).The results highlight that blocks exert both positive and negative effects on shear strength,dilation,and block breakage factor(BF),depending on *** indicate 40%and 60%as critical VBPs,revealing distinct shear strength trends within this range,contrary to the dominant downward *** positively impact dilation and BF between 20%and 50%VBP,while negatively affecting them beyond this *** skeleton inherently promotes stable dilatancy under normal stress increments and intensifies stress dependency of shear *** in dilation angle concerning normal stress and VBP suggest the potential for characterizing this factor using equivalent strength and roughness,akin to rockfill *** assessments of equivalent strength revealed positive effects of blocks when VBP was between 30%and 70%.Lastly,the findings indicate that blocks notably impact pre-and post-peak behaviors by reducing shear stiffness and inducing local hardening *** study also discusses the similarities and distinctions in the function of blocks within soil-like and rock-like *** offers new insights into the exact role of blocks in bimrock shear behavior beyond the traditional interpretation through the variation of friction and cohesion.

关键词： Bimrock Rock-like matrix Shear behavior Shear strength Shear dilation Block breakage

Xiamen after 20 Years of Ecological Transformation

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China Today 2025年第1期74卷 66-68页

作者： ZACHARY g.LUNDQUIST 不详

The efforts Xiamen has made in ecological protection over the last 20 years have helped it become a beautiful and clean *** years ago,I had the opportunity to travel to the city of Xiamen in southeastern China’s Fujian ***,due to the fact that I was in a rush,I did not have the chance to see the whole *** memory of Xiamen was its pleasant climate and unforgettable beauty-I knew if I ever got the opportunity,I would revisit this *** years went by until I was able to return to this city *** emerging from the airport,I realized that I had grown older,while Xiamen was becoming increasingly youthful and *** exactly had given this city such vitality?

关键词： Ecological Xiamen Transformation

Comparative analysis of cast-in-place post-tensioned and steel-concrete composite bridge bent caps

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Journal of modern Transportation 2017年第3期25卷 194-204页

作者： Nur yazdani Francisco D.B.Ruiz Department of Civil Engineering University of Texas at Arlington Structural Engineer Ferrovial-Agroman

The complexity of the IH-635 managed Lanes Project, located in Dallas County, Texas, posed several technical and constructive challenges, leading to the adoption of solutions different from the traditional. Two alternative solutions for the pier cap on one of the bridge crossings over IH-35E in the IH-635 project were analyzed in this case study, a cast-in-place post-tensioned concrete cap and an innovative prefabricated steel-concrete com- posite cap. The approach was to use an estimation of direct costs for material and labor and consideration of con- struction time schedules. A supplementary numerical modeling confirmed that both alternatives behave elasti- cally under imposed loads. The direct cost of material and labor for the two alternatives were close. However, the composite alternative required 13 days less construction time, resulting in substantial cost savings from traffic closing in the very busy traffic corridor. Traffic closing costs were substantially higher than the direct costs, especially for the post-tensioned cap. The quantification of the benefits allows more confidence in the utilization of the composites caps, leading to faster completion of bridge projects and substantial economic savings.

关键词： Bridge pier cap Bridge bent - Post-tensionedstructure Steel-concrete cap Cost estimation Construction schedule Traffic closing cost

Application of the invasive weed optimization algorithm to economic dispatch problems

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Frontiers in Energy 2012年第3期6卷 255-259页

作者： T. JAYABARATHI Afshin yazdani V. RAmESH School of Electrical Engineering VIT University Vellore 632014 India

In this paper the invasive weed optimization algorithm has been applied to a variety of economic dispatch （ED） problems. The ED problem is concerned with minimizing the fuel cost by optimally loading the electrical generators which are committed to supply a given demand. Some involve prohibited operating zones, transmission losses and valve point loading. In general, they are non-linear non-convex optimization problems which cannot be directly solved by conventional methods. In this work the invasive weed algorithm, a meta-heuristic method inspired by the proliferation of weeds, has been applied to four numerical examples and has resulted in promising solutions compared to published results.

关键词： economic dispatch (ED) invasive weed optimization non-convexity prohibited operating zones(POZ) valve point loading meta-heuristic

Provincial clustering of malaria in Iran between 2005 and 2014

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Asian Pacific Journal of Tropical medicine 2020年第4期13卷 162-168页

作者： Vahid moqarabzadeh Ahmad Ali Enayati Ahmad Raeisi Fatemeh Nikpour Jamshid yazdani Charati Department of Biostatistics&Epidemiology School of HealthMazandaran University of Medical SciencesSariIran medical Entomology Mazandaran University of Medical SciencesSariIran Department of medical Entomology and Vector Control School of Public HealthTehran University of Medical SciencesTehranIran Department of Environmental Chemical Pollutants and Pesticides Institute for Environmental ResearchTehran University of Medical SciencesTehranIran Department of Biostatistics Health Sciences Research CenterAddiction InstituteMazandaran University of Medical SciencesSariIran

Objective: To reveal the provincial clustering of malaria in Iran between 2005 and 2014 based on the epidemiologic factors and the climatic indicators affecting the disease. methods: This was a descriptive-analytical study using malaria and meteorological data from the malaria Elimination Programme of the ministry of Health and medical Education and National meteorological Organization. After standardization, the aggregate data was used to produce 10-year means for each province. The data analysis included grouping the provinces with respect to factors using hierarchical clustering method and Kruskal-Wallis test to examine the difference between clusters using SPSS ver.23. Results: The hierarchical clustering stratified the provinces' in 5 clusters. Kruskal-Wallis H test revealed a significant difference in the incidence rate per 100000 population (P=0.001), male gender (P=0.001), Iranian nationality (P=0.001), Afghan nationality (P=0.003), Pakistani nationality (P=0.001), urban residence (P=0.006), rural residence (P=0.004), autochthonous cases (P=0.007), average minimum temperature (P=0.001), average maximum temperature (P=0.007), average relative humidity (P=0.011), average pressure level (P=0.038), prevailing wind direction (P=0.023), average wind speed (P=0.031) and average precipitation sum (P=0.002) among the clusters. Conclusions: The results of this study and stratification of the provinces could help health policy makers to better manage malaria by allocating resources accordingly.

关键词： malaria Cluster analysis Iran