27 research outputs found

    Information Bank of Phytoremedial Plants in Arid and Semi-Arid Rangeland Ecosystems

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    Accumulation of heavy elements by human activities in ecosystems and food chains created hazards for human, plants and ecosystems. Among different methods of managing heavy elements in the environment, using phytoremedial plants has emerged as an efficient way to reduce the concentration of heavy metals in soils (Shtangeeva, 2008). This research examines the efficiency of this heavy metal reduction strategy in dry rangeland ecosystems

    Factors Affecting Rangeland Utilization by Ranchers in the Golestan Rangelands, Iran

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    In Iran, rangelands produce most of the forage resources for livestock. There are various types of traditional grazing systems for the utilization of rangelands, including the consultative, collective and operational multiplayer systems. In the consultative type, certain people are selected by the ranchers and they determine the utilization method and manage grazing. In the collective system, all ranchers use rangeland in common. In the operational multiplayer system, rangelands are used in common but the ranchers share rangelands by rancher-rancher negotiation. This research was undertaken to investigate the human factors as rancher\u27s effect on rangeland utilization in different systems above mentioned

    Shape Optimization of an abrupt contraction using numerical streamlining

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    This research was conducted to find a reliable technique to shape an abrupt contraction for minimizing the energy loss. The method may find broader applications in design of variety of transitional cross-sections in hydraulic structures. The streamlines in a 2-D contraction were calculated through solving the potential flow equations in rectangular and curvilinear coordinates. The natural cubic spline equations were applied to approximate the shape of streamlines. The streamlines close to the solid boundary, usually those that represent 5 and 95 percent of the discharge, were repeatedly mapped onto the solid boundary in a trial and error procedure until a negligible difference between two consecutive shapes was achieved. This procedure was applied through a code developed in C++, namely Streamlining Program Code or SPC. The initial and final shapes were used to validate SPC by the help of a robust CFD software, OpenFOAM. In a 2-D contraction with contraction ratio of 5, entrance velocity of 1 m/s and outlet pressure of atmosphere (P = 0 pa), the maximum spatial difference between the stream lines found by the code and OpenFOAM was limited to 2.74% that occurred in the entrance of the contraction. Finally, according to the validation, the streamlining technique and the code could successfully applied to shape optimization of hydraulic structures

    Investigation of the Fire Effects on Some Physico-Chemical Characteristics of Soil (Case Study: Miankaleh Rangeland, Iran)

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    Fire is one of the ecological factors that can have positive and negative effects on ecosystem processes. Nevertheless, prescribed burning is considered to be an important tool for grassland management, particularly to manipulate the balance between grasses and shrubs (Scheintaub et al. 2009). In Iran, for example, Khodagholi et al. (2001) in the Samirom rangelands of Isfahan Province suggest that fire reduces the shrubs cover and production and leads to the expansion of grasses. Sharifi and Imani (2006) showed that in the semi-steppe of Khalkhal Province shrub cover decreased in contrast to permanent grasses after fire was applied. However, others report that fire can reduce production and plant diversity due to affects on the range soil properties. This research investigated the effects of fire on some soil physico-chemical characteristics in the Miankaleh rangeland in northern Iran

    Water repellent effect and dimension stability of beech wood impregnated with nano-zinc oxide

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    The objective of this study was to quantify the influence of zinc oxide nanoparticles (nano-ZnO) on the water repellency and dimensional stability of beech wood. Beech wood blocks were treated with a nano-ZnO solution at four treatment levels (0, 10,000, 20,000, and 40,000 ppm) using a modified dip method. Also, a thermal treatment was performed at 60 and 120°C. After conditioning the samples, water absorption, volumetric swelling, water repellency effectiveness, and anti-shrink/anti-swell efficiency were determined within 24 h of soaking time. The results indicated that the nano-ZnO used for wood modification greatly improved dimensional stability and reduced the hygroscopicity of the wood. In addition, the Fourier-transform infrared spectroscopy (FTIR) analysis suggested a strong interaction between the nano-ZnO and the chemical components of wood. The heat treatment effectively improved the effects of nano-ZnO

    Mineral Content in Some Species of Leguminosae in Bandar Torkaman Plain Rangelands, Iran

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    Improving the forage quality and balance of their minerals in rangeland ecosystems is important for rangeland managers to improve livestock productivity (Mohamed et al. 2003; Epstein and Bloom 2005). This research investigated the amount of several minerals; Calcium (Ca), Phosphorus (P), Potassium (K) and Magnesium (Mg), in some important species of Leguminosae including Medicago sativa, Trifolium repens, Trifolium pratense and Lathyrus pratensis, that are grazed by livestock in the Bandar Torkaman plain rangelands in north of Iran

    The Effect of Intravenous Ketamine in Suicidal Ideation of Emergency Department Patients

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    Introduction: Suicidal ideation is an emergent problem in the Emergency Department (ED) that often complicates patient disposition and discharge. It has been shown that ketamine possesses fast acting antidepressant and anti-suicidal effects. This study was conducted to examine the effects of a single intravenous bolus of ketamine on patients with suicidal ideations in ED. Methods: Forty-nine subjects with suicidal ideations with or without an unsuccessful suicide attempt, received 0.2 mg/kg of ketamine. Scale for suicidal ideation (SSI) and Montgomery-Abserg depression rating scale (MADRS) were evaluated before and 40, 80 and 120 minutes after drug intervention. The results were compared using the paired t-test and patients were followed up 10 days after ED admission for remnant suicide ideation. Results: SSI (df: 3, 46; F=80.7; p<0.001) and MADRS (df: 3, 46; F=87.2; p<0.001) scores significantly dropped after ketamine injection; the SSI score before and after 20, 40, and 80 minutes of ketamine injection were 23.0±6.7, 16.2±5.2, 14.3±4.3, and 13.6±4.0 respectively. The MADRS scores were 38.2±9.3, 25.6±7.1, 22.7±6.3, and 22.1±5.95 at the same time intervals. 25.5% of patients were hospitalized, 63.3% received medications and 12.2% discharged. 6.2% of patients had suicidal ideations ten days after ED disposition.  Conclusion: It seems that Ketamine couldn't be a good choice for fast reduction of suicidal ideations in ED patients. Further studies are needed to determine the optimal dose of ketamine for different patients

    Coordinated System Reliability Assessment And Production Cost Simulation In Transmission Planning Of Eastern Interconnection

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    This paper presents a transmission need analysis for the Eastern Interconnection (EI) using a coordinated technical approach consisting of system reliability assessment (SRA) and production cost simulation (PCS). As North American Transmission Systems are being evolved with increasing levels of renewable energy resources such as wind, solar, storage, biomass, hydro, etc., maintaining grid reliability and managing transmission congestion cost are becoming increasingly challenging. It also poses complexity and challenges in technical and economic planning of the transmission grid. The coordinated SRA and PCS were conducted to assess transmission reliability and congestion for the interconnected grids of the EI in a 10-year planning horizon. The paper discusses new automation tools and models developed for such assessment including case studies showing the applicability of the coordinated methodology and developed models

    THE EFFECT OF PHYSICIANS’ GENDER AND EXPERIENCE ON PERSIAN MEDICAL INTERACTIONS

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    This study focusing on physician-patient interactions aimed to find out whetherphysicians’ gender and experience influence Persian doctor-patient interactions. Sopower strategies in physician-patient interactions were extracted and categorized toexplore the relationship between physicians’ gender and experience and power strategies.Fieldwork was conducted in clinics and hospitals of Rafsanjan city in Iran. One hundredphysician-patient consultations were audiotaped and transcribed during 2011-2012.Woods’ (2006) view was used to examine four strategies of power and knowledge ontheir talk. The findings pointed out the importance of investigating discourse of medicinein order to improve medical consultations, especially physician-patient interactions.Our study confirmed some previous assertions that physician-patient interactionswere asymmetrical. Physicians controlled and dominated the medical consultations byquestioning, interruptions, directive statements and tag questions. The analysis of the datarevealed that all power strategies were applied in Iranian physician-patient interactions.The results of Chi-Square tests indicated that there was a significant relationship betweenpower strategies and physicians’ experience and gender. It was concluded that the femaleand inexperienced physicians tended to control consultations by questioning, interruption,directives and tag questions more than the male and experienced physicians

    Primary Angle Closure Glaucoma-associated Genetic Polymorphisms in Northeast Iran

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    Purpose: To evaluate the association of five different polymorphisms from a genomewide- associated study with susceptibility to glaucoma in the northeast Iranian population. Methods: Hundred and thirty patients with primary angle closure glaucoma (PACG) and 130 healthy controls were genotyped for the polymorphic regions with the aid of tetraamplification refractory mutation system-polymerase chain reaction. The association of these variants with the disease susceptibility was measured statistically with the logistic regression method. Results: Hundred and thirty patients with PACG (53 males, 77 females) with a mean age of 64.5 ± 6.2 years and 130 healthy control subjects (51 males, 79 females) with a mean age of 64.0 ± 5.7 years were selected for evaluation. There was a significant association between rs3816415 (P = 0.005), rs736893 (P < 0.001), rs7494379 (P < 0.001), and rs1258267 (P = 0.02) with PACG susceptibility. This association could not be shown for rs3739821. Conclusion: It was revealed that studied variants in GLIS3, EPDR1, FERMT2, and CHAT genes can contribute to the incidence of PACG. Additional studies in other populations are needed to evaluate DPM2-FAM102A
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