A considerable proportion of Iran＇s territory is covered with arid and semi-arid rangelands and mismanagement and overexploitation of those rangelands have resulted in serious ecological degradation. Thus, the need i...A considerable proportion of Iran＇s territory is covered with arid and semi-arid rangelands and mismanagement and overexploitation of those rangelands have resulted in serious ecological degradation. Thus, the need is pressing to examine the present species composition and the relationships with environmental factors for providing the needed scientific references to species conservation and ecological rehabilitation efforts. The aims of this study were to examine the species composition and to delineate the most important factors influencing the distributions of plant species and groups in the northern rangelands of Isfahan Province （Iran） using two-way indicator species analysis （TWINSPAN）, detrended correspondence analysis （DCA）, principal component analysis （PCA）, and canonical correspondence analysis （CCA）. Field investigations were conducted in the growing season of 2014 using stratified random method in 22 homogeneous sampling units. In total, 75 plant species belonging to 52 genera and 19 families were identified. The most important families were Asteraceae and Papilionaceae, the most important genera were Astragalus, Cousinia, and Acanthophyllum, and the most important species were Artemisia aucheri and Artemisia sieberi. Plant species were classified into 10 groups using TWINSPAN. DCA was used to estimate the magnitude of changes in species composition along the first two ordination axes to provide gradient length estimations for PCA and CCA ordinations. The first three PCA axes and the first three CCA axes demonstrated similar cumulative percentage of variance, indicating that the environmental factors （selected by PCA） used in CCA ordination were acceptable for explaining the species composition and the distributions. CCA ordination showed that the first axis was closely related to elevation, slope, surface bare soil cover, surface litter cover, gravel proportion, organic matter, total nitrogen, CaCO3 content, and grazing intensity and that the second axis was closely related to sand proportion, silt proportion, clay proportion, and saturation percentage. Among these factors, elevation was the most effective factor to separate the plant groups and grazing was the major cause of rangeland degradation.展开更多
This study aimed to assess trace element concentrations in the hair of street children. Nutritional status was assessed by 24 hours’ dietary recall and anthropometric measurements. Data analysis found that Br, Sc, Sm...This study aimed to assess trace element concentrations in the hair of street children. Nutritional status was assessed by 24 hours’ dietary recall and anthropometric measurements. Data analysis found that Br, Sc, Sm and Ti concentrations show a normal distribution, and there is no significant difference between street children and control group. However, in the street children’s hair, the levels of Au, U, V are decreased and the levels of Co, La, Sb, Th are increased compared to the control group.展开更多
Humans are always effect to their surroundings,which makes it possible to create habitable environments and create habitat patterns that fit the surrounding environment.The interaction between human being and environm...Humans are always effect to their surroundings,which makes it possible to create habitable environments and create habitat patterns that fit the surrounding environment.The interaction between human being and environment either in the form of human effect on the environment or the environment effect on the human,cannot be considered out of the environment.According to this approach in archaeology,environmental factors have an important role in assessing settlements in each period.In addition to the recognition of the degree of environmental impact,this approach makes the degree of adaptation of the habitats with the dominant environmental conditions possible.As geospatial tools become more powerful,GIS archaeology has evolved as well,making it possible to visualize ancient settlements and analyze changes in the use of space over time.By incorporating historic map data,physical details of an area’s landscape and known information about past inhabitants,archaeologists can accurately predict the positions of sites with cultural,historical relevance.In this research Iron Age III(800-550 B.C)sites in the west and northwest of Isfahan were studied via GIS.The area studied is one of the most important but unknown areas of archaeological research due to its location in the center of the Iranian plateau and a link between the north-west and the south-west of the country.The environmental characteristics of the studied area have attracted the attention of humans since ancient times.Therefore,it was considered necessary to conduct archaeological excavations.To achieve this goal,the area was first studied archaeologically.As a result of this survey,approximately 50 ancient sites were identified which included the statistical population used for analysis.The effect of environmental variables including altitude,slope(percentage and direction),climate,geological structure,distances and proximity to water resources,land use and proximity to communication paths on the distribution of settlements in the study area was investigated.Through analytical-descriptive method,the factors affecting the formation and distribution of the establishment patterns of the period in question were examind.After analyzing the information and maps,the results indicated that among all the factors,three environmental factors were the most important in the formation of ancient settlements of the Iron Age III era in the west and northwest of Isfahan:factors relating to water resources,proximity to communication paths,and slope percentage and direction.展开更多
Anthropogenic activities have caused the accumulation of heavy metals in the soil environment. Pollution of the soils significantly reduces environmental quality and affects human health. In many recent studies, magne...Anthropogenic activities have caused the accumulation of heavy metals in the soil environment. Pollution of the soils significantly reduces environmental quality and affects human health. In many recent studies, magnetic susceptibility ts have been used for pollution monitoring. The objective of this research was to determine the spatial variability of magnetic properties and selected heavy metals and the effect of land use on their variability in the surface soils of the Isfahan region, Central Iran. A total of 158 composite surface （0-5 cm） samples of calcareous soils were collected from an area of about 700 km2, located along a cross-border transect from Isfahan City to a steel plant, covering urban, industrial, agricultural, and uncultivated land uses. Concentrations of copper （Cu）, zinc （Zn）, lead （Pb）, manganese （Mn）, iron （Fe）, nickel （Ni）, chromium （Cr）, and cobalt （Co） and magnetic parameters, magnetic susceptibility at low frequency （xlf）, natural remanent magnetization （NRM）, saturation isothermal remanent magnetization （SIRM）, and isothermal remanent magnetization at the field of 100 mT （IRM100mT） and the backfield of 100 mT （IRM-100mT）, were measured in all the soil samples. Results showed that magnetic susceptibility in the urban and industrial land topsoils （0-5 cm） samples was significantly higher than that in the agricultural and uncultivated land soils in the study area. Concentrations of Cu, Zn, Pb, Mn, and Fe were positively correlated with magnetic properties （xlf, IRM100mT, SIRM, IRM-100mT, and NRM）, which could be attributed to their inputs from traffic emissions and industrial activities at the study sites. Ni and Cr concentrations showed significant negative correlations with magnetic properties. No significant correlation was found between Co concentration and magnetic parameters. The Tomlinson pollution load index （PLI） showed significant correlation with the magnetic properties （xlf, IRM100mT, SIRM, IRM-100mT, and NRM）. The spatial distribution of the selected heavy metals and xlf in the study area suggested that activities at the urban and industrial land sites caused greater pollution as compared to that at the study sites of other land uses. The concentrations of Cu and Zn seemed to have been affected by anthropogenic sources, whereas Ni, Cr, and Co were mainly controlled by natural sources in the study area. Moreover, the concentrations of soil Pb and Fe in the study area could be affected by both lithologic and anthropogenic sources. The magnetic parameters appeared to be a proxy measure for the degree of heavy metal contamination and could be a potential method for the detection and mapping of contaminated soils.展开更多
The presence of heavy metals（HMs） in particulate matters（PMs） particularly fine particles such as PM2.5 poses potential risk to the health of human being. The purpose of this study was to analyze the contents of H...The presence of heavy metals（HMs） in particulate matters（PMs） particularly fine particles such as PM2.5 poses potential risk to the health of human being. The purpose of this study was to analyze the contents of HMs in PM2.5 in the atmospheric monitoring stations in Isfahan city,Iran, in different seasons between March 2014 and March 2015 and their source identification using principle component analysis（PCA）. The samples of PM2.5 were taken using a high volume sampler in 7 monitoring stations located throughout the city and industrial zones since March 2014 to March 2015. The HMs content of the samples was measured using ICP-MS.The results showed that the concentrations of As, Cd and Ni were in a range of 23–36, 1–12,and 5–76 ng/m3 at all the stations which exceeded the US-EPA standards. Furthermore,the concentrations of Cr and Cu reached to 153 and 167 ng/m3 in some stations which were also higher than the standard levels. Depending on the potential sources of HMs, their concentration in PM2.5 through the various seasons was different. PCA illustrated that the different potential sources of HMs in the atmosphere, showing that the most important sources of HMs originated from fossil fuel combustion, abrasion of vehicle tires, industrial activities（e.g., iron and steel industries） and dust storms. Management and control of air pollution of industrial plants and vehicles are suggested for decreasing the risk of the HMs in the region.展开更多
Objective: To determine the antibiotic resistance patterns of the Acinetobacter(A.) baumannii complex isolates that cause the confirmed infection. Methods: The present descriptive study was performed from March 2016 t...Objective: To determine the antibiotic resistance patterns of the Acinetobacter(A.) baumannii complex isolates that cause the confirmed infection. Methods: The present descriptive study was performed from March 2016 to March 2018 in three referral hospitals in Isfahan, Iran. All A. baumannii complex strains isolated from different clinical samples were identified by conventional phenotypic methods and antibiotic susceptibility pattern was detected. After the clinical investigation, contaminated samples were excluded and the source(hospital/community) and site of the infection were determined. Data on antibiotic susceptibility testing were extracted from WHONET software and analysis was done with SPSS.Results: From 254 patients who had confirmed A. baumannii complex infection, 158(62.20%) cases were male, 27(10.63%) were less than 20 years old, 172(67.72%) had healthcare-associated infections and 96(37.79%) were admitted in intensive care units. The most frequent infection was bloodstream infections(111, 43.70%). Our results showed that most of the isolates were resistant to most of the antibiotics(more than 75.00%) and a lower rate of non-susceptibility was observed against minocycline(20, 44.44%) and colistin(0%). The rate of multidrug-resistant isolates was 88.97%. There was no significant difference between resistance of A. baumannii complex isolates according to age. However, the resistance to amikacin and minocycline and the rate of multidrug resistance(MDR) were significantly different between males and females. In patients with healthcare associated infection(HAI), MDR isolates were significantly different regarding admission in ICU ward. Resistance to levofloxacin and ciprofloxacin were lower in isolates from patients with bloodstream infections in comparison to other diagnoses.Conclusions: In our study, a high level of antibiotic resistance was detected in both community-acquired and healthcare-associated A. baumannii complex infections. Appropriate antibiotic prescription in a clinical setting is an essential need for the control and prevention of A. baumannii resistant infections.展开更多
Introduction: Worldwide specific diseases are jeopardizing people’s health in the world as well as in Iran. Chronic renal failure as a developed and irreversible failure is usually progressive. End Stage Renal Diseas...Introduction: Worldwide specific diseases are jeopardizing people’s health in the world as well as in Iran. Chronic renal failure as a developed and irreversible failure is usually progressive. End Stage Renal Disease (ESRD) is a situation when renal function is not sufficient to preserve one’s life leading to acute uremia resulting in dialysis and/or kidney transplantation for the patients. Although dialysis methods bring about complications for the patients, peritoneal dialysis is relatively cost-effective and more convenient to survive. The present study aimed to investigate (the) Etiologic factor of renal failure and imposed complications of peritoneal dialysis in the patients of Isfahan Alzahra hospital. Materials and Methods: It was a cross-sectional descriptive study conducted on 67 patients in Isfahan Peritoneal Dialysis Center. The data from the patients were collected through a two-section questionnaire whose first section was allocated to demographic information and the second part was related to the disease and complications of peritoneal dialysis. The collected data were analyzed by SPSS version 18. Results: The findings showed that there were 39 (58%) males and 28 (42%) females. Mean age of the subjects was 48 (18.8) years old. Regarding marital status, 65% were married and 35% were single. Considering complications, 28 subjects (53.5%) had infectious complications while 24 subjects (46.2%) had non-infectious complications. The highest frequency in etiologic factor of renal failure was diabetes mellitus in 29 subjects (43.9%) and the lowest for polycystic kidney in 2 subjects (3%);in addition, hypertension was observed in 51 subjects (77.3%). Discussion: The most frequent and important complication of peritoneal dialysis catheters is infection, which may result in catheter loss and discontinuation of peritoneal dialysis (PD). Diabetes and hypertension were found as the most important etiologic factors for renal failure. They should also be considered as two major risk factors in prevention of renal diseases.展开更多
Reuse of wastewater for agriculture and green spaces purposes is significant.A mean yearly precipitation in Esfahan is 150 mm.The drinking water and agriculture usually used underground resources in the city.Gray wate...Reuse of wastewater for agriculture and green spaces purposes is significant.A mean yearly precipitation in Esfahan is 150 mm.The drinking water and agriculture usually used underground resources in the city.Gray water recycling is known as a suitable option today.Delivering all the water requirements of a home from refined water rises the cost of water.Whereas the essential water quality for garden,toilet and irrigation is less than drinking water.Therefore,the aim of this study is to analyze the evaluation of gray water and estimate the amount of recycle gray water which can use for drinking water with innovation method in Esfahan region in Iran.Previous studies did not measure the value of recycling gray water with new method of waste water treatment that can use for drinking purpose.In this study,gray water in Esfahan city is measured and technical aspects of its recycling is examined.Because of the lack of referable guidelines and official technical reports,studies from other similar countries applied in this study and on the basis of which the amount of recoverable gray water was calculated.Evaluations indicates that the overall recovery of gray water in Esfahan saves nine million cubic meters of water.The price of the rial of this value established on water is 190 billion Rials.Given the lack of water sources in Esfahan,the recycle of gray water seems to be a good option,however more research is required to select a recovery strategy.展开更多
Pedestrianization is an urban revitalization strategy to enhance sustainability and livability in car-oriented cities.Despite many studies in this research field,the effects of pedestrianization on the economy of citi...Pedestrianization is an urban revitalization strategy to enhance sustainability and livability in car-oriented cities.Despite many studies in this research field,the effects of pedestrianization on the economy of cities in developing countries still need further investigation.Additionally,the impact of this strategy on the tenant mix of com-mercial and historical areas in Middle East countries is nebulous.To address these inadequacies,we considered Chaharbagh Abbasi street,located in the heart of Isfahan,Iran,and investigated the impact of a pedestrianization project with particular emphasis on how it affects the economic sustainability of existent commercial fabric.Pre-and post-project data along with field observations and quantifications used to assess structural replacements in trade,were analyzed with SPSS and ArcGIS software.The results revealed unexpected outcomes,such as the closure of some traditional businesses(27.5%),a stagnation in sales(69%)and a decrease in job offers(84%)leading the local economy to a fragile situation.Conversely,it was found that the footfall volume increased by 64% and 73% from the retailers’and pedestrians’viewpoints.This evolution along with a wide opening of food and beverage stores(approximately 60%)makes the post-pedestrianization results more promising than earlier predictions.In conclusion,these findings reinforce the importance of pedestrian streets in revitalizing economic activities in historical and commercial areas from the perspective of economic sustainability.Due to the lack of similar investigations in Middle East countries,these findings can support decision-makers and urban planners to take preventive measures in preserving the diversity of individual small shops for upcoming urban rehabilitation projects in terms of pedestrianization.展开更多
Aims Desertification results in ecological and biological diminution of the earth,and can happen naturally or cause by anthropogenic activities.This process especially affects arid and semi-arid regions,such as the Is...Aims Desertification results in ecological and biological diminution of the earth,and can happen naturally or cause by anthropogenic activities.This process especially affects arid and semi-arid regions,such as the Isfahan region,where the spread of desertification is reaching critical proportions.The aim of this study is to use remotely sensed data to review the trend of desertification in the northern of Isfahan,Iran.Methods Multi-temporal images were employed to evaluate the trend of desertification,specifically the TM and ETM+ data of September,1990 and September,2001.Geometric and radiometric corrections were applied to each image prior to image processing and supervised classification,and vegetation indices were applied to produce a land use map of each image in nine classes.The land use classifications in the two map images were compared and changes between land use classes were detected over the 11 year period using a fuzzy and post-classification technique.Important findings The maps and their comparison with false color composite images showed the differences efficiently.With the fuzzy and post-classification method the land use changes were sited on the map.Fuzzy confirmed 53% changed area and 47% unchanged areas in the study region.The results verify the desertification expansion in the study areas.Because of poor land management,agricultural lands converted to desert and abandoned areas,and some marginal pasture lands had to be changed to agricultural land which are desertification spreading according to United Nations Conference on Desertification(UNCOD).Also farmland and pastures have been converted to urban and industrial areas,and the rangelands have been spoiled due to opencast mine excavations.With the mine margins eroding as well as their debris accumulating on the pasture lands,desertification has become worse.Three areas of less-elevated mountains have remained unchanged.This study confirmed that the anthropogenic activities accelerated the desertification process and severely endangered the remaining areas.展开更多
Objective: To study earthquake planning and crisis management with an emphasis on the facilities, utilities, and services of the health care centers of Tiran and Karvan County, Isfahan Province. Methods: This is a des...Objective: To study earthquake planning and crisis management with an emphasis on the facilities, utilities, and services of the health care centers of Tiran and Karvan County, Isfahan Province. Methods: This is a descriptive-analytical survey based on the quantitative and qualitative characteristics of Tiran and Karvan County Health Care Centers(HCCs). Twenty quantitative and qualitative indicators were derived from the studied HCCs and analyzed using the strengths, weaknesses, opportunities and threats analysis technique. The top crisis management strategies were identified and a number of strategies and solutions were proposed. Results: The HCC utilities such as water, electricity, gas, and heating and cooling systems were in average condition, whereas the facilities of the majority of HCCs were in vulnerable-to-average condition. In addition, they sustained relatively high degree of instability which calls for reassessment and effective policies to minimize weaknesses and eliminate threats using strengths and opportunities. Conclusions: It is recommended that the condition of Tiran and Karvan County HCCs be enhanced by distributing new HCCs based on the population density, expanding the road network and creating vast, wide-open spaces to enable field hospital construction in times of crisis.展开更多
Multiple sclerosis (MS) is an inflammatory demyelinating disease of central nervous system (CNS) that mostly affects young adults. The etiology of MS includes both genetic and environmental factors. A single nucleotid...Multiple sclerosis (MS) is an inflammatory demyelinating disease of central nervous system (CNS) that mostly affects young adults. The etiology of MS includes both genetic and environmental factors. A single nucleotide polymorphism (SNP) linked with autoimmune disorders predisposition, identified by Genome-Wide Association Study (GWAS) among genes which immunologically related are considerably over signified. The goal of the current study is investigation of the association between rs1800795 (-174 G/C) polymorphism in the promoter of IL6 gene variant with the risk of RRMS in a subset of Iranian population. In this case-control study, 110 healthy subjects and 110 patients with RRMS were included. DNA was extracted from blood samples and polymerase chain reaction (PCR) was used to amplify the fragment of interest contain rs1800795 SNP, restriction fragment length polymorphism (RFLP) method was performed for genotyping of the DNA samples with a specific restriction enzyme (NlaIII). SPSS for Windows software (version 18.0;SPSS, Chicago, IL) was used for statistical analysis. No significant differences were found between RRMS patients and healthy controls with respect to the distribution of the cytokine gene polymorphism investigated. Odds ratio adjusted for age, sex, and blood groups (except A blood group) has displayed similar outcomes. These results indicate that the rs1800795 SNP is not a susceptibility gene variant for development of RRMS in the Isfahan population. Further studies using new data on complex transcriptional interactions between IL-6 polymorphic sites are necessary to determine IL-6 haplotype influence on susceptibility to RRMS.展开更多
Background: Mycosis Fungoides (MF) is the most common and indolent form of Cutaneuse T-cell Lymphomas (CTCL), that usually occurs in old adults. Objectives: To determine epidemiologic features and patients characteris...Background: Mycosis Fungoides (MF) is the most common and indolent form of Cutaneuse T-cell Lymphomas (CTCL), that usually occurs in old adults. Objectives: To determine epidemiologic features and patients characteristics of MF in Isfahan (Iran). Methods: We performed a retrospective study in MF clinic of alzahra hospital that is the main center for treatment of MF patients in Isfahan (Iran) and evaluated clinicopathologic features. Results: In 3 years 25 patients were referred to Alzahra MF clinic. 18 patients diagnosed as MF. Seven (38.9%) patients were male and 11 (61.1%) were female with male to female ratio of 1:1.57. The mean age of patients was 41.06 years. 88.9% of our patients were in stages ΙA and ΙB. Conclusion: Most of our patients presented in early stages that were similar to other studies, while male: female ratio is different from other studies.展开更多
Terminals and stations as one of the most important parts of transportation systems and also as the arteries of the country’s economy life undertake significant role in adjustment and regulation of the traffic pulse ...Terminals and stations as one of the most important parts of transportation systems and also as the arteries of the country’s economy life undertake significant role in adjustment and regulation of the traffic pulse of cities and roads. Urban furniture is one of the components considered in urban designing and as a part of the whole city, it defines the urban identity and structure. In today’s world, the importance of designing the urban equipment and furniture is to an extent that even active architects in the field of industrial designing are invited for designing and performing the urban furniture and equipment. Urban designing is a thing beyond making some flower box in squares and determining bus and taxi stations. Evidently, what gives identity to the city or according to the saying of “Sansovini”, what has tranquility for the city’s residents and creates attraction for foreigner tourists, not only include the mass buildings and streets traffic, but also include landscape, parks and furniture of the city. Standard designing of bus terminals like other urban furniture influences on urban face and it can have significant role in satisfaction of domestic tourists and increase and propagation of using of terminals. In this research, it has been attempted that the effect of furniture in the terminals of Isfahan city on domestic tourists should be studied that for this purpose, descriptive-analytic method has been used and data have been collected through field and library studies and secondary sources by using of SWOT model.展开更多
Monitoring of rangeland forage production at specified spatial and temporal scales is necessary for grazing management and also for implementation of rehabilitation projects in rangelands. This study focused on the ca...Monitoring of rangeland forage production at specified spatial and temporal scales is necessary for grazing management and also for implementation of rehabilitation projects in rangelands. This study focused on the capability of a generalized regression neural network（GRNN） model combined with GIS techniques to explore the impact of climate change on rangeland forage production. Specifically, a dataset of 115 monitored records of forage production were collected from 16 rangeland sites during the period 1998–2007 in Isfahan Province, Central Iran. Neural network models were designed using the monitored forage production values and available environmental data（including climate and topography data）, and the performance of each network model was assessed using the mean estimation error（MEE）, model efficiency factor（MEF）, and correlation coefficient（r）. The best neural network model was then selected and further applied to predict the forage production of rangelands in the future（in 2030 and 2080） under A1 B climate change scenario using Hadley Centre coupled model. The present and future forage production maps were also produced. Rangeland forage production exhibited strong correlations with environmental factors, such as slope, elevation, aspect and annual temperature. The present forage production in the study area varied from 25.6 to 574.1 kg/hm^2. Under climate change scenario, the annual temperature was predicted to increase and the annual precipitation was predicted to decrease. The prediction maps of forage production in the future indicated that the area with low level of forage production（0–100 kg/hm^2） will increase while the areas with moderate, moderately high and high levels of forage production（≥100 kg/hm^2） will decrease both in 2030 and in 2080, which may be attributable to the increasing annual temperature and decreasing annual precipitation. It was predicted that forage production of rangelands will decrease in the next couple of decades, especially in the western and southern parts of Isfahan Province. These changes are more pronounced in elevations between 2200 and 2900 m. Therefore, rangeland managers have to cope with these changes by holistic management approaches through mitigation and human adaptations.展开更多
Advanced intensity measures(IMs)based on an inelastic deformation spectrum improved the evaluation of the median engineering demand parameters(EDPs)and reduced dispersion.In this regard,an optimized two-degreefreedom(...Advanced intensity measures(IMs)based on an inelastic deformation spectrum improved the evaluation of the median engineering demand parameters(EDPs)and reduced dispersion.In this regard,an optimized two-degreefreedom(2DOF)modal pushover-based scaling procedure(2DMPS)has been developed for a nonlinear dynamic analysis of asymmetric in-plan buildings.The 2DMPS procedure scales ground motions to approach close enough to a target value of the inelastic displacement of the first-mode inelastic 2DOF modal stick,extended for structures with significant contributions of higher modes.Further,4-,6-and 13-story RC SMRF buildings were selected for analyses using ground motion records scaled by the 2DMPS procedure,the modal pushover-based scaling method(MPS),and ASCE/SEI 7-16 scaling procedures.The median values of EDPs on scaled records closely matched the benchmark results.The bias in the EDP values due to the scaled records in every group regarding their median value was lower than the dispersion of the 21 unscaled records.These results generally demonstrate the accuracy and efficiency of the 2DMPS method.Additionally,the 2DOF modal stick’s inelastic response spectra are better suited for calculating seismic demands for one-way asymmetric-plan structures than the SDOF inelastic response spectra.展开更多
Subcritical reactors(SCRs)or subcritical assemblies(SCAs)are the main infrastructure for designing power reactors.These reactors are widely used for training and research because of their high level of inherent safety...Subcritical reactors(SCRs)or subcritical assemblies(SCAs)are the main infrastructure for designing power reactors.These reactors are widely used for training and research because of their high level of inherent safety.The objective of this study is to design a subcritical reactor using a pressurized water reactor(PWR)conventional fuel following two safety points.In the first approach,deeply placed SCR cores with an infinite multiplication factor(k_(∞))of less than unity were identified using the DRAGON lattice code.In the second approach,subcritical reactor cores with an effective multiplication factor(k_(eff))of less than unity were determined by coupling the cell calculations of the DRAGON lattice code and core calculations of the DONJON code.For the deeply subcritical reactor design,it was found that the reactor would remain inherently subcritical while using fuel rods with ^(235)U enrichment of up to 0.9%,regardless of the pitch of the fuel rods.In the second approach,the optimal pitches(1.3 to 2.3 cm)were determined for different fuel enrichment values from 1 to 5%.Subsequently,the k_(eff) was obtained for a fuel rod arrangement of 8×8 to 80×80,and the states in which the reactor would be subcritical were determined for different fuel enrichments at the corresponding optimal pitch.To validate the models used in the DRAGON and DONJON codes,the k_(eff) of the Isfahan Light Water Subcritical Reactor(LWSCR)was experimentally measured and compared with the results of the calculations.Finally,the effects of fuel and moderator temperature changes were investigated to ensure that the designed assemblies remained in the subcritical state at all operational temperatures.展开更多
A terrestrial relay-aided reconfigurable intelligent surface(RIS)system with decode,re-encode and forward(DRF)relaying scheme is presented where the RIS effectively contributes to both sourceto-destination and relay-t...A terrestrial relay-aided reconfigurable intelligent surface(RIS)system with decode,re-encode and forward(DRF)relaying scheme is presented where the RIS effectively contributes to both sourceto-destination and relay-to-destination signaling.While in the conventional decode and forward(DF)relaying scheme,the source signal is merely duplicated in the relay and the time intervals are equally allocated to the source and relay nodes,this paper considers DRF relaying scheme where versatile time-sharing is adopted for the source and relay nodes which can be optimized based on the relative coordinates of the involved nodes.Two protocols namely unidirectional connection(UC)and bidirectional connection(BC)are proposed based on the source awareness from the relay’s successful reception.The outage probability(OP)performance for both protocols and both DF and DRF relaying schemes is analyzed and tight approximations are obtained.The numerical results show the out-performance of the DRF over the DF relaying scheme in the both UC and BC protocols.Equipped with the obtained system OP,the system throughput is defined and the optimum system throughput is obtained by optimizing the system rate and the timesharing between the source and the relay.Analytical results are corroborated in the numerical examples.展开更多
Overt and harmful diabetes mellitus(DM)has detrimental effects on individuals and,by extension,the community.Among the microvascular DM complications is diabetic retinopathy(DR).DR may cause irreversible vision deteri...Overt and harmful diabetes mellitus(DM)has detrimental effects on individuals and,by extension,the community.Among the microvascular DM complications is diabetic retinopathy(DR).DR may cause irreversible vision deterioration in cases of poor blood glucose regulation.Changes in vascular permeability are key trigger points for diabetic macular edema(DME),a condition characterized by the accumulation of fluid in the macula.The development of vascular endothelial growth factor(VEGF)pathway inhibitors has provided a pathogenesis-based treatment approach for DME.Optical coherence tomography(OCT)provides highresolution imaging of the anatomy,including the aging of DME and its structural damage,in distinct morphologic subtypes of macular edema,thereby supporting the assessment of macular edema treatment.The availability of repeated OCT monitoring provides clinical reassurance through the treatment.OCT angiography(OCTA)provides retinal blood flow maps with high spatial resolution.The ability promotes an understanding of disease pathogenesis and facilitates the implementation of new therapeutic methods.This review compares the potential of OCT and OCTA in the diagnosis and treatment of DME,as well as their respective therapeutic applications.展开更多
MXene-based smart contact lenses demonstrate a cutting-edge advancement in wearable ophthalmic technology,combining real-time biosensing,therapeutic capabilities,and user comfort in a single platform.These devices tak...MXene-based smart contact lenses demonstrate a cutting-edge advancement in wearable ophthalmic technology,combining real-time biosensing,therapeutic capabilities,and user comfort in a single platform.These devices take the advantage of the exceptional electrical conductivity,mechanical flexibility,and biocompatibility of two-dimensional MXenes to enable noninvasive,tear-based monitoring of key physiological markers such as intraocular pressure and glucose levels.Recent developments focus on the integration of transparent MXene films into the conventional lens materials,allowing multifunctional performance including photothermal therapy,antimicrobial and anti-inflammation protection,and dehydration resistance.These innovations offer promising strategies for ocular disease management and eye protection.In addition to their multifunctionality,improvements in MXene synthesis and device engineering have enhanced the stability,transparency,and wearability of these lenses.Despite these advances,challenges remain in long-term biostability,scalable production,and integration with wireless communication systems.This review summarizes the current progress,key challenges,and future directions of MXene-based smart contact lenses,highlighting their transformative potential in next-generation digital healthcare and ophthalmic care.展开更多
文摘A considerable proportion of Iran＇s territory is covered with arid and semi-arid rangelands and mismanagement and overexploitation of those rangelands have resulted in serious ecological degradation. Thus, the need is pressing to examine the present species composition and the relationships with environmental factors for providing the needed scientific references to species conservation and ecological rehabilitation efforts. The aims of this study were to examine the species composition and to delineate the most important factors influencing the distributions of plant species and groups in the northern rangelands of Isfahan Province （Iran） using two-way indicator species analysis （TWINSPAN）, detrended correspondence analysis （DCA）, principal component analysis （PCA）, and canonical correspondence analysis （CCA）. Field investigations were conducted in the growing season of 2014 using stratified random method in 22 homogeneous sampling units. In total, 75 plant species belonging to 52 genera and 19 families were identified. The most important families were Asteraceae and Papilionaceae, the most important genera were Astragalus, Cousinia, and Acanthophyllum, and the most important species were Artemisia aucheri and Artemisia sieberi. Plant species were classified into 10 groups using TWINSPAN. DCA was used to estimate the magnitude of changes in species composition along the first two ordination axes to provide gradient length estimations for PCA and CCA ordinations. The first three PCA axes and the first three CCA axes demonstrated similar cumulative percentage of variance, indicating that the environmental factors （selected by PCA） used in CCA ordination were acceptable for explaining the species composition and the distributions. CCA ordination showed that the first axis was closely related to elevation, slope, surface bare soil cover, surface litter cover, gravel proportion, organic matter, total nitrogen, CaCO3 content, and grazing intensity and that the second axis was closely related to sand proportion, silt proportion, clay proportion, and saturation percentage. Among these factors, elevation was the most effective factor to separate the plant groups and grazing was the major cause of rangeland degradation.
文摘This study aimed to assess trace element concentrations in the hair of street children. Nutritional status was assessed by 24 hours’ dietary recall and anthropometric measurements. Data analysis found that Br, Sc, Sm and Ti concentrations show a normal distribution, and there is no significant difference between street children and control group. However, in the street children’s hair, the levels of Au, U, V are decreased and the levels of Co, La, Sb, Th are increased compared to the control group.
文摘Humans are always effect to their surroundings,which makes it possible to create habitable environments and create habitat patterns that fit the surrounding environment.The interaction between human being and environment either in the form of human effect on the environment or the environment effect on the human,cannot be considered out of the environment.According to this approach in archaeology,environmental factors have an important role in assessing settlements in each period.In addition to the recognition of the degree of environmental impact,this approach makes the degree of adaptation of the habitats with the dominant environmental conditions possible.As geospatial tools become more powerful,GIS archaeology has evolved as well,making it possible to visualize ancient settlements and analyze changes in the use of space over time.By incorporating historic map data,physical details of an area’s landscape and known information about past inhabitants,archaeologists can accurately predict the positions of sites with cultural,historical relevance.In this research Iron Age III(800-550 B.C)sites in the west and northwest of Isfahan were studied via GIS.The area studied is one of the most important but unknown areas of archaeological research due to its location in the center of the Iranian plateau and a link between the north-west and the south-west of the country.The environmental characteristics of the studied area have attracted the attention of humans since ancient times.Therefore,it was considered necessary to conduct archaeological excavations.To achieve this goal,the area was first studied archaeologically.As a result of this survey,approximately 50 ancient sites were identified which included the statistical population used for analysis.The effect of environmental variables including altitude,slope(percentage and direction),climate,geological structure,distances and proximity to water resources,land use and proximity to communication paths on the distribution of settlements in the study area was investigated.Through analytical-descriptive method,the factors affecting the formation and distribution of the establishment patterns of the period in question were examind.After analyzing the information and maps,the results indicated that among all the factors,three environmental factors were the most important in the formation of ancient settlements of the Iron Age III era in the west and northwest of Isfahan:factors relating to water resources,proximity to communication paths,and slope percentage and direction.
基金Supported by the Isfahan University of Technology,Iran
文摘Anthropogenic activities have caused the accumulation of heavy metals in the soil environment. Pollution of the soils significantly reduces environmental quality and affects human health. In many recent studies, magnetic susceptibility ts have been used for pollution monitoring. The objective of this research was to determine the spatial variability of magnetic properties and selected heavy metals and the effect of land use on their variability in the surface soils of the Isfahan region, Central Iran. A total of 158 composite surface （0-5 cm） samples of calcareous soils were collected from an area of about 700 km2, located along a cross-border transect from Isfahan City to a steel plant, covering urban, industrial, agricultural, and uncultivated land uses. Concentrations of copper （Cu）, zinc （Zn）, lead （Pb）, manganese （Mn）, iron （Fe）, nickel （Ni）, chromium （Cr）, and cobalt （Co） and magnetic parameters, magnetic susceptibility at low frequency （xlf）, natural remanent magnetization （NRM）, saturation isothermal remanent magnetization （SIRM）, and isothermal remanent magnetization at the field of 100 mT （IRM100mT） and the backfield of 100 mT （IRM-100mT）, were measured in all the soil samples. Results showed that magnetic susceptibility in the urban and industrial land topsoils （0-5 cm） samples was significantly higher than that in the agricultural and uncultivated land soils in the study area. Concentrations of Cu, Zn, Pb, Mn, and Fe were positively correlated with magnetic properties （xlf, IRM100mT, SIRM, IRM-100mT, and NRM）, which could be attributed to their inputs from traffic emissions and industrial activities at the study sites. Ni and Cr concentrations showed significant negative correlations with magnetic properties. No significant correlation was found between Co concentration and magnetic parameters. The Tomlinson pollution load index （PLI） showed significant correlation with the magnetic properties （xlf, IRM100mT, SIRM, IRM-100mT, and NRM）. The spatial distribution of the selected heavy metals and xlf in the study area suggested that activities at the urban and industrial land sites caused greater pollution as compared to that at the study sites of other land uses. The concentrations of Cu and Zn seemed to have been affected by anthropogenic sources, whereas Ni, Cr, and Co were mainly controlled by natural sources in the study area. Moreover, the concentrations of soil Pb and Fe in the study area could be affected by both lithologic and anthropogenic sources. The magnetic parameters appeared to be a proxy measure for the degree of heavy metal contamination and could be a potential method for the detection and mapping of contaminated soils.
基金financially supported by the Fundamental Research Funds for the central University,China University of Geosciences(Wuhan)(No.CUG150602)the International collaboration project funded by the China University of Geosciences(Wuhan)
文摘The presence of heavy metals（HMs） in particulate matters（PMs） particularly fine particles such as PM2.5 poses potential risk to the health of human being. The purpose of this study was to analyze the contents of HMs in PM2.5 in the atmospheric monitoring stations in Isfahan city,Iran, in different seasons between March 2014 and March 2015 and their source identification using principle component analysis（PCA）. The samples of PM2.5 were taken using a high volume sampler in 7 monitoring stations located throughout the city and industrial zones since March 2014 to March 2015. The HMs content of the samples was measured using ICP-MS.The results showed that the concentrations of As, Cd and Ni were in a range of 23–36, 1–12,and 5–76 ng/m3 at all the stations which exceeded the US-EPA standards. Furthermore,the concentrations of Cr and Cu reached to 153 and 167 ng/m3 in some stations which were also higher than the standard levels. Depending on the potential sources of HMs, their concentration in PM2.5 through the various seasons was different. PCA illustrated that the different potential sources of HMs in the atmosphere, showing that the most important sources of HMs originated from fossil fuel combustion, abrasion of vehicle tires, industrial activities（e.g., iron and steel industries） and dust storms. Management and control of air pollution of industrial plants and vehicles are suggested for decreasing the risk of the HMs in the region.
文摘Objective: To determine the antibiotic resistance patterns of the Acinetobacter(A.) baumannii complex isolates that cause the confirmed infection. Methods: The present descriptive study was performed from March 2016 to March 2018 in three referral hospitals in Isfahan, Iran. All A. baumannii complex strains isolated from different clinical samples were identified by conventional phenotypic methods and antibiotic susceptibility pattern was detected. After the clinical investigation, contaminated samples were excluded and the source(hospital/community) and site of the infection were determined. Data on antibiotic susceptibility testing were extracted from WHONET software and analysis was done with SPSS.Results: From 254 patients who had confirmed A. baumannii complex infection, 158(62.20%) cases were male, 27(10.63%) were less than 20 years old, 172(67.72%) had healthcare-associated infections and 96(37.79%) were admitted in intensive care units. The most frequent infection was bloodstream infections(111, 43.70%). Our results showed that most of the isolates were resistant to most of the antibiotics(more than 75.00%) and a lower rate of non-susceptibility was observed against minocycline(20, 44.44%) and colistin(0%). The rate of multidrug-resistant isolates was 88.97%. There was no significant difference between resistance of A. baumannii complex isolates according to age. However, the resistance to amikacin and minocycline and the rate of multidrug resistance(MDR) were significantly different between males and females. In patients with healthcare associated infection(HAI), MDR isolates were significantly different regarding admission in ICU ward. Resistance to levofloxacin and ciprofloxacin were lower in isolates from patients with bloodstream infections in comparison to other diagnoses.Conclusions: In our study, a high level of antibiotic resistance was detected in both community-acquired and healthcare-associated A. baumannii complex infections. Appropriate antibiotic prescription in a clinical setting is an essential need for the control and prevention of A. baumannii resistant infections.
文摘Introduction: Worldwide specific diseases are jeopardizing people’s health in the world as well as in Iran. Chronic renal failure as a developed and irreversible failure is usually progressive. End Stage Renal Disease (ESRD) is a situation when renal function is not sufficient to preserve one’s life leading to acute uremia resulting in dialysis and/or kidney transplantation for the patients. Although dialysis methods bring about complications for the patients, peritoneal dialysis is relatively cost-effective and more convenient to survive. The present study aimed to investigate (the) Etiologic factor of renal failure and imposed complications of peritoneal dialysis in the patients of Isfahan Alzahra hospital. Materials and Methods: It was a cross-sectional descriptive study conducted on 67 patients in Isfahan Peritoneal Dialysis Center. The data from the patients were collected through a two-section questionnaire whose first section was allocated to demographic information and the second part was related to the disease and complications of peritoneal dialysis. The collected data were analyzed by SPSS version 18. Results: The findings showed that there were 39 (58%) males and 28 (42%) females. Mean age of the subjects was 48 (18.8) years old. Regarding marital status, 65% were married and 35% were single. Considering complications, 28 subjects (53.5%) had infectious complications while 24 subjects (46.2%) had non-infectious complications. The highest frequency in etiologic factor of renal failure was diabetes mellitus in 29 subjects (43.9%) and the lowest for polycystic kidney in 2 subjects (3%);in addition, hypertension was observed in 51 subjects (77.3%). Discussion: The most frequent and important complication of peritoneal dialysis catheters is infection, which may result in catheter loss and discontinuation of peritoneal dialysis (PD). Diabetes and hypertension were found as the most important etiologic factors for renal failure. They should also be considered as two major risk factors in prevention of renal diseases.
文摘Reuse of wastewater for agriculture and green spaces purposes is significant.A mean yearly precipitation in Esfahan is 150 mm.The drinking water and agriculture usually used underground resources in the city.Gray water recycling is known as a suitable option today.Delivering all the water requirements of a home from refined water rises the cost of water.Whereas the essential water quality for garden,toilet and irrigation is less than drinking water.Therefore,the aim of this study is to analyze the evaluation of gray water and estimate the amount of recycle gray water which can use for drinking water with innovation method in Esfahan region in Iran.Previous studies did not measure the value of recycling gray water with new method of waste water treatment that can use for drinking purpose.In this study,gray water in Esfahan city is measured and technical aspects of its recycling is examined.Because of the lack of referable guidelines and official technical reports,studies from other similar countries applied in this study and on the basis of which the amount of recoverable gray water was calculated.Evaluations indicates that the overall recovery of gray water in Esfahan saves nine million cubic meters of water.The price of the rial of this value established on water is 190 billion Rials.Given the lack of water sources in Esfahan,the recycle of gray water seems to be a good option,however more research is required to select a recovery strategy.
文摘Pedestrianization is an urban revitalization strategy to enhance sustainability and livability in car-oriented cities.Despite many studies in this research field,the effects of pedestrianization on the economy of cities in developing countries still need further investigation.Additionally,the impact of this strategy on the tenant mix of com-mercial and historical areas in Middle East countries is nebulous.To address these inadequacies,we considered Chaharbagh Abbasi street,located in the heart of Isfahan,Iran,and investigated the impact of a pedestrianization project with particular emphasis on how it affects the economic sustainability of existent commercial fabric.Pre-and post-project data along with field observations and quantifications used to assess structural replacements in trade,were analyzed with SPSS and ArcGIS software.The results revealed unexpected outcomes,such as the closure of some traditional businesses(27.5%),a stagnation in sales(69%)and a decrease in job offers(84%)leading the local economy to a fragile situation.Conversely,it was found that the footfall volume increased by 64% and 73% from the retailers’and pedestrians’viewpoints.This evolution along with a wide opening of food and beverage stores(approximately 60%)makes the post-pedestrianization results more promising than earlier predictions.In conclusion,these findings reinforce the importance of pedestrian streets in revitalizing economic activities in historical and commercial areas from the perspective of economic sustainability.Due to the lack of similar investigations in Middle East countries,these findings can support decision-makers and urban planners to take preventive measures in preserving the diversity of individual small shops for upcoming urban rehabilitation projects in terms of pedestrianization.
文摘Aims Desertification results in ecological and biological diminution of the earth,and can happen naturally or cause by anthropogenic activities.This process especially affects arid and semi-arid regions,such as the Isfahan region,where the spread of desertification is reaching critical proportions.The aim of this study is to use remotely sensed data to review the trend of desertification in the northern of Isfahan,Iran.Methods Multi-temporal images were employed to evaluate the trend of desertification,specifically the TM and ETM+ data of September,1990 and September,2001.Geometric and radiometric corrections were applied to each image prior to image processing and supervised classification,and vegetation indices were applied to produce a land use map of each image in nine classes.The land use classifications in the two map images were compared and changes between land use classes were detected over the 11 year period using a fuzzy and post-classification technique.Important findings The maps and their comparison with false color composite images showed the differences efficiently.With the fuzzy and post-classification method the land use changes were sited on the map.Fuzzy confirmed 53% changed area and 47% unchanged areas in the study region.The results verify the desertification expansion in the study areas.Because of poor land management,agricultural lands converted to desert and abandoned areas,and some marginal pasture lands had to be changed to agricultural land which are desertification spreading according to United Nations Conference on Desertification(UNCOD).Also farmland and pastures have been converted to urban and industrial areas,and the rangelands have been spoiled due to opencast mine excavations.With the mine margins eroding as well as their debris accumulating on the pasture lands,desertification has become worse.Three areas of less-elevated mountains have remained unchanged.This study confirmed that the anthropogenic activities accelerated the desertification process and severely endangered the remaining areas.
文摘Objective: To study earthquake planning and crisis management with an emphasis on the facilities, utilities, and services of the health care centers of Tiran and Karvan County, Isfahan Province. Methods: This is a descriptive-analytical survey based on the quantitative and qualitative characteristics of Tiran and Karvan County Health Care Centers(HCCs). Twenty quantitative and qualitative indicators were derived from the studied HCCs and analyzed using the strengths, weaknesses, opportunities and threats analysis technique. The top crisis management strategies were identified and a number of strategies and solutions were proposed. Results: The HCC utilities such as water, electricity, gas, and heating and cooling systems were in average condition, whereas the facilities of the majority of HCCs were in vulnerable-to-average condition. In addition, they sustained relatively high degree of instability which calls for reassessment and effective policies to minimize weaknesses and eliminate threats using strengths and opportunities. Conclusions: It is recommended that the condition of Tiran and Karvan County HCCs be enhanced by distributing new HCCs based on the population density, expanding the road network and creating vast, wide-open spaces to enable field hospital construction in times of crisis.
文摘Multiple sclerosis (MS) is an inflammatory demyelinating disease of central nervous system (CNS) that mostly affects young adults. The etiology of MS includes both genetic and environmental factors. A single nucleotide polymorphism (SNP) linked with autoimmune disorders predisposition, identified by Genome-Wide Association Study (GWAS) among genes which immunologically related are considerably over signified. The goal of the current study is investigation of the association between rs1800795 (-174 G/C) polymorphism in the promoter of IL6 gene variant with the risk of RRMS in a subset of Iranian population. In this case-control study, 110 healthy subjects and 110 patients with RRMS were included. DNA was extracted from blood samples and polymerase chain reaction (PCR) was used to amplify the fragment of interest contain rs1800795 SNP, restriction fragment length polymorphism (RFLP) method was performed for genotyping of the DNA samples with a specific restriction enzyme (NlaIII). SPSS for Windows software (version 18.0;SPSS, Chicago, IL) was used for statistical analysis. No significant differences were found between RRMS patients and healthy controls with respect to the distribution of the cytokine gene polymorphism investigated. Odds ratio adjusted for age, sex, and blood groups (except A blood group) has displayed similar outcomes. These results indicate that the rs1800795 SNP is not a susceptibility gene variant for development of RRMS in the Isfahan population. Further studies using new data on complex transcriptional interactions between IL-6 polymorphic sites are necessary to determine IL-6 haplotype influence on susceptibility to RRMS.
文摘Background: Mycosis Fungoides (MF) is the most common and indolent form of Cutaneuse T-cell Lymphomas (CTCL), that usually occurs in old adults. Objectives: To determine epidemiologic features and patients characteristics of MF in Isfahan (Iran). Methods: We performed a retrospective study in MF clinic of alzahra hospital that is the main center for treatment of MF patients in Isfahan (Iran) and evaluated clinicopathologic features. Results: In 3 years 25 patients were referred to Alzahra MF clinic. 18 patients diagnosed as MF. Seven (38.9%) patients were male and 11 (61.1%) were female with male to female ratio of 1:1.57. The mean age of patients was 41.06 years. 88.9% of our patients were in stages ΙA and ΙB. Conclusion: Most of our patients presented in early stages that were similar to other studies, while male: female ratio is different from other studies.
文摘Terminals and stations as one of the most important parts of transportation systems and also as the arteries of the country’s economy life undertake significant role in adjustment and regulation of the traffic pulse of cities and roads. Urban furniture is one of the components considered in urban designing and as a part of the whole city, it defines the urban identity and structure. In today’s world, the importance of designing the urban equipment and furniture is to an extent that even active architects in the field of industrial designing are invited for designing and performing the urban furniture and equipment. Urban designing is a thing beyond making some flower box in squares and determining bus and taxi stations. Evidently, what gives identity to the city or according to the saying of “Sansovini”, what has tranquility for the city’s residents and creates attraction for foreigner tourists, not only include the mass buildings and streets traffic, but also include landscape, parks and furniture of the city. Standard designing of bus terminals like other urban furniture influences on urban face and it can have significant role in satisfaction of domestic tourists and increase and propagation of using of terminals. In this research, it has been attempted that the effect of furniture in the terminals of Isfahan city on domestic tourists should be studied that for this purpose, descriptive-analytic method has been used and data have been collected through field and library studies and secondary sources by using of SWOT model.
文摘Monitoring of rangeland forage production at specified spatial and temporal scales is necessary for grazing management and also for implementation of rehabilitation projects in rangelands. This study focused on the capability of a generalized regression neural network（GRNN） model combined with GIS techniques to explore the impact of climate change on rangeland forage production. Specifically, a dataset of 115 monitored records of forage production were collected from 16 rangeland sites during the period 1998–2007 in Isfahan Province, Central Iran. Neural network models were designed using the monitored forage production values and available environmental data（including climate and topography data）, and the performance of each network model was assessed using the mean estimation error（MEE）, model efficiency factor（MEF）, and correlation coefficient（r）. The best neural network model was then selected and further applied to predict the forage production of rangelands in the future（in 2030 and 2080） under A1 B climate change scenario using Hadley Centre coupled model. The present and future forage production maps were also produced. Rangeland forage production exhibited strong correlations with environmental factors, such as slope, elevation, aspect and annual temperature. The present forage production in the study area varied from 25.6 to 574.1 kg/hm^2. Under climate change scenario, the annual temperature was predicted to increase and the annual precipitation was predicted to decrease. The prediction maps of forage production in the future indicated that the area with low level of forage production（0–100 kg/hm^2） will increase while the areas with moderate, moderately high and high levels of forage production（≥100 kg/hm^2） will decrease both in 2030 and in 2080, which may be attributable to the increasing annual temperature and decreasing annual precipitation. It was predicted that forage production of rangelands will decrease in the next couple of decades, especially in the western and southern parts of Isfahan Province. These changes are more pronounced in elevations between 2200 and 2900 m. Therefore, rangeland managers have to cope with these changes by holistic management approaches through mitigation and human adaptations.
文摘Advanced intensity measures(IMs)based on an inelastic deformation spectrum improved the evaluation of the median engineering demand parameters(EDPs)and reduced dispersion.In this regard,an optimized two-degreefreedom(2DOF)modal pushover-based scaling procedure(2DMPS)has been developed for a nonlinear dynamic analysis of asymmetric in-plan buildings.The 2DMPS procedure scales ground motions to approach close enough to a target value of the inelastic displacement of the first-mode inelastic 2DOF modal stick,extended for structures with significant contributions of higher modes.Further,4-,6-and 13-story RC SMRF buildings were selected for analyses using ground motion records scaled by the 2DMPS procedure,the modal pushover-based scaling method(MPS),and ASCE/SEI 7-16 scaling procedures.The median values of EDPs on scaled records closely matched the benchmark results.The bias in the EDP values due to the scaled records in every group regarding their median value was lower than the dispersion of the 21 unscaled records.These results generally demonstrate the accuracy and efficiency of the 2DMPS method.Additionally,the 2DOF modal stick’s inelastic response spectra are better suited for calculating seismic demands for one-way asymmetric-plan structures than the SDOF inelastic response spectra.
文摘Subcritical reactors(SCRs)or subcritical assemblies(SCAs)are the main infrastructure for designing power reactors.These reactors are widely used for training and research because of their high level of inherent safety.The objective of this study is to design a subcritical reactor using a pressurized water reactor(PWR)conventional fuel following two safety points.In the first approach,deeply placed SCR cores with an infinite multiplication factor(k_(∞))of less than unity were identified using the DRAGON lattice code.In the second approach,subcritical reactor cores with an effective multiplication factor(k_(eff))of less than unity were determined by coupling the cell calculations of the DRAGON lattice code and core calculations of the DONJON code.For the deeply subcritical reactor design,it was found that the reactor would remain inherently subcritical while using fuel rods with ^(235)U enrichment of up to 0.9%,regardless of the pitch of the fuel rods.In the second approach,the optimal pitches(1.3 to 2.3 cm)were determined for different fuel enrichment values from 1 to 5%.Subsequently,the k_(eff) was obtained for a fuel rod arrangement of 8×8 to 80×80,and the states in which the reactor would be subcritical were determined for different fuel enrichments at the corresponding optimal pitch.To validate the models used in the DRAGON and DONJON codes,the k_(eff) of the Isfahan Light Water Subcritical Reactor(LWSCR)was experimentally measured and compared with the results of the calculations.Finally,the effects of fuel and moderator temperature changes were investigated to ensure that the designed assemblies remained in the subcritical state at all operational temperatures.
文摘A terrestrial relay-aided reconfigurable intelligent surface(RIS)system with decode,re-encode and forward(DRF)relaying scheme is presented where the RIS effectively contributes to both sourceto-destination and relay-to-destination signaling.While in the conventional decode and forward(DF)relaying scheme,the source signal is merely duplicated in the relay and the time intervals are equally allocated to the source and relay nodes,this paper considers DRF relaying scheme where versatile time-sharing is adopted for the source and relay nodes which can be optimized based on the relative coordinates of the involved nodes.Two protocols namely unidirectional connection(UC)and bidirectional connection(BC)are proposed based on the source awareness from the relay’s successful reception.The outage probability(OP)performance for both protocols and both DF and DRF relaying schemes is analyzed and tight approximations are obtained.The numerical results show the out-performance of the DRF over the DF relaying scheme in the both UC and BC protocols.Equipped with the obtained system OP,the system throughput is defined and the optimum system throughput is obtained by optimizing the system rate and the timesharing between the source and the relay.Analytical results are corroborated in the numerical examples.
文摘Overt and harmful diabetes mellitus(DM)has detrimental effects on individuals and,by extension,the community.Among the microvascular DM complications is diabetic retinopathy(DR).DR may cause irreversible vision deterioration in cases of poor blood glucose regulation.Changes in vascular permeability are key trigger points for diabetic macular edema(DME),a condition characterized by the accumulation of fluid in the macula.The development of vascular endothelial growth factor(VEGF)pathway inhibitors has provided a pathogenesis-based treatment approach for DME.Optical coherence tomography(OCT)provides highresolution imaging of the anatomy,including the aging of DME and its structural damage,in distinct morphologic subtypes of macular edema,thereby supporting the assessment of macular edema treatment.The availability of repeated OCT monitoring provides clinical reassurance through the treatment.OCT angiography(OCTA)provides retinal blood flow maps with high spatial resolution.The ability promotes an understanding of disease pathogenesis and facilitates the implementation of new therapeutic methods.This review compares the potential of OCT and OCTA in the diagnosis and treatment of DME,as well as their respective therapeutic applications.
文摘MXene-based smart contact lenses demonstrate a cutting-edge advancement in wearable ophthalmic technology,combining real-time biosensing,therapeutic capabilities,and user comfort in a single platform.These devices take the advantage of the exceptional electrical conductivity,mechanical flexibility,and biocompatibility of two-dimensional MXenes to enable noninvasive,tear-based monitoring of key physiological markers such as intraocular pressure and glucose levels.Recent developments focus on the integration of transparent MXene films into the conventional lens materials,allowing multifunctional performance including photothermal therapy,antimicrobial and anti-inflammation protection,and dehydration resistance.These innovations offer promising strategies for ocular disease management and eye protection.In addition to their multifunctionality,improvements in MXene synthesis and device engineering have enhanced the stability,transparency,and wearability of these lenses.Despite these advances,challenges remain in long-term biostability,scalable production,and integration with wireless communication systems.This review summarizes the current progress,key challenges,and future directions of MXene-based smart contact lenses,highlighting their transformative potential in next-generation digital healthcare and ophthalmic care.
