1,242 research outputs found
Analysis of Technical Efficiency and Varietal Differences in Pistachio Production in Iran Using a Meta-Frontier Analysis
This paper reports on an analysis of technical efficiency and varietal differences in pistachio production in Iran. A random sample of 475 farmers was selected from the province of Kerman in 2003 and 2004. In this study, farmers are classified into three groups according to the variety of tree they planted. The three main varieties of pistachio trees planted are Kalleh- Ghuchi, Fandoghi and Akbari. The technical efficiency indices are computed using three approaches. First, a standard stochastic production frontier was employed using pooled data. Secondly, stochastic frontier production functions were estimated for each variety (separately). Lastly, the meta-frontier approach was used because production varieties and technologies are expected to differ between the three varieties. Use of this method enabled technical efficiency scores to be corrected by the coefficient of the variety-technology gap ratio (VTGR). Estimates of the frontier were obtained assuming a translog functional form. Results indicate that the mean values of technical efficiency in 2003 and 2004 for the pooled frontier, variety group frontiers and meta-frontier across all data are 54 per cent, 55 per cent and 62 per cent, respectively. The mean value of VTGR in 2003 and 2004 varies from 0.58 for the Kalleh-Ghuchi variety to 0.68 for the Fandoghi variety. These results show the importance of taking into account the differences in frontiers imposed by different tree varieties.pistachio, stochastic meta-frontier, production function, technical efficiency, Iranian agriculture, Productivity Analysis, C21, Q12, Q16, Q55, R58,
Spirituality Concept by Health Professionals in Iran: A Qualitative Study
Background. For years, researchers have sought to provide a clear definition of spirituality and its features and consequences, but the definitions provided of this concept still lack transparency. The present qualitative research was conducted to clarify this concept within the religious-cultural context of Iran. Materials and Methods. The present conventional qualitative content analysis was conducted with an inductive approach. Data were collected through semistructured interviews with 17 spiritual health experts and activists selected through purposive sampling. Results. Three themes emerged from the analysis of the data, including (1) the structure of spirituality, (2) defects in the conceptualization of spirituality, and (3) spirituality in practice, which are explained in this paper with their relevant subthemes and codes. The definition which this study proposes for this concept is that "spirituality is the sublime aspect of human existence bestowed on all humans in order for them to traverse the path of transcendence that is closeness to God (Allah)." Conclusion. The definition provided by this study is similar to the previous definitions of this concept in its main part (transcendence) and in incorporating a God-centered view of spirituality within the context of an Islamic society. This definition has implications for health services' education, research, and practice in similar societies. © 2016 Nadereh Memaryan et al
Study of mycoflora in cultured Indian white shrimp (Penaeus indicus) in Abadan, Iran
The development of the commercial culture of penaeid shrimps has been accompanied by the occurrence of infectious and noninfectious diseases. The most important penaeid diseases are caused by organisms that are part of the normal microflora of penaeids. In 1998, the samples were collected from five farms in Ghofase area (Ahadan) 2-5 ponds in each farm. The shrimps of these ponds were preserved in full hygienic conditions, from each pond, at least 5 samples were collected and then transferred to the Aquatic Diseases Laboratory of Khouzestan Fisheries Research Center. The main tissues of Gill, Hemolymph, Hepatopancreas and cuticle of live-shrimps were studied in the laboratory. In this research, a total of 40 fungal species were isolated from different tissues with high abundance in Hepatopancrease (19 species) and Hemolymph (12 species). Aspergillus niger was identified as the most abundant species
Correction: Vocal imitation of percussion sounds: On the perceptual similarity between imitations and imitated sounds
[This corrects the article DOI: 10.1371/journal.pone.0219955.]
Active role of the necrotic zone in desensitization of hypoxic macrophages and regulation of CSC-fate: A hypothesis
Fast-proliferating cancer cells in the hypoxic region face a shortage of oxygen and nutrients, undergo necrotic cell death, and release numerous signaling components. Hypoxia-induced chemo-attractants signal for macrophages/monocytes to clear debris and return the system to steady state. Accordingly, macrophages arrange into pre-necrotic positions, where they are continuously exposed to stress signals. It can thus be hypothesized that gradual alteration of gene expression in macrophages eventually turns offtheir phagocytic machinery. Uncleared cell corpses within the hypoxic region potentially provide a rich source of building blocks for anaerobic metabolism of cancer stem cells via macropinocytosis, and are conceivably implicated in tumor progression and invasion. © 2018 Mehrabi, Amini and Mehrabi
Commensalism and parasitic infestation in crayfish (Astacus leptodactylus Eschscholtz, 1823) of Aras Dam Reservoir, Iran
The freshwater crayfish of the Aras Reservoir is an important economic fisheries resource of West Azarbaijan, Iran. This study was conducted to evaluate the prevalence of parasitic infestation of Crayfish seasonally in this area in 2010. Among 390 different sizes of Astacus leptodactylus which were examined, a range of ectocommensals or ectosymbionts from a number of different phyla including 9 orders and 11 classes infested the different anatomic units of the surface and appendages such as gills, head, thorax, abdomen, walking legs, uropod, telson, antennae and antennulae of freshwater crayfish. Common groups such as peritrich ciliates, suctorian ciliates, free living nematodes, branchiobdellids, and algae, copepods, rotifers and oligochaetes have also been observed in association with freshwater crayfish
Specific Resistance Genes in Wheat Chinese Landrace ‘Wangshuibai’ against Two Iranian Mycosphaerella Graminicola Isolates
Abstract Septoria tritici blotch, caused by the fungus Mycosphaerella graminicola, is currently the major foliar disease of wheat world-wide, and new sources of resistance and knowledge about the genetics of resistance are needed to improve breeding for resistance against this disease. An F10 recombinant inbred population from a cross between ‘Wangshuibai’ (Chinese landrace) and the susceptible cultivar ‘Seri82’ was tested at seedling stage under controlled greenhouse conditions. Two isolate-specific genes for resistance to Iranian M.graminicola isolates IPO08002 and IPO08003 were detected on Chromosomes 2BL and 7DS, respectively. For both genes the resistance was derived from ‘Wangshuibai’ at positions where Stb9 (on 2BL) and Stb4 (on 7DS) have been reported previously. These two genes are closely linked to microsatellite markers, which can be used for marker-assisted selection. ‘Wangshuibai’ may therefore be a valuable source of resistance to STB for wheat breeding, especially in Mediterranean environments
A Spoof Surface Plasmon Polaritons (SSPPs) Based Dual-Band-Rejection Filter with Wide Rejection Bandwidth.
This paper presents a novel single-layer dual band-rejection-filter based on Spoof Surface Plasmon Polaritons (SSPPs). The filter consists of an SSPP-based transmission line, as well as six coupled circular ring resonators (CCRRs) etched among ground planes of the center corrugated strip. These resonators are excited by electric-field of the SSPP structure. The added ground on both sides of the strip yields tighter electromagnetic fields and improves the filter performance at lower frequencies. By removing flaring ground in comparison to prevalent SSPP-based constructions, the total size of the filter is significantly decreased, and mode conversion efficiency at the transition from co-planar waveguide (CPW) to the SSPP line is increased. The proposed filter possesses tunable rejection bandwidth, wide stop bands, and a variety of different parameters to adjust the forbidden bands and the filter's cut-off frequency. To demonstrate the filter tunability, the effect of different elements like number (n), width (WR), radius (RR) of CCRRs, and their distance to the SSPP line (yR) are surveyed. Two forbidden bands, located in the X and K bands, are 8.6-11.2 GHz and 20-21.8 GHz. As the proof-of-concept, the proposed filter was fabricated, and a good agreement between the simulation and experiment results was achieved
Optimizing an Adaptive Neuro-Fuzzy Inference System for Spatial Prediction of Landslide Susceptibility Using Four State-of-the-art Metaheuristic Techniques.
Four state-of-the-art metaheuristic algorithms including the genetic algorithm (GA), particle swarm optimization (PSO), differential evolutionary (DE), and ant colony optimization (ACO) are applied to an adaptive neuro-fuzzy inference system (ANFIS) for spatial prediction of landslide susceptibility in Qazvin Province (Iran). To this end, the landslide inventory map, composed of 199 identified landslides, is divided into training and testing landslides with a 70:30 ratio. To create the spatial database, thirteen landslide conditioning factors are considered within the geographic information system (GIS). Notably, the spatial interaction between the landslides and mentioned conditioning factors is analyzed by means of frequency ratio (FR) theory. After the optimization process, it was shown that the DE-based model reaches the best response more quickly than other ensembles. The landslide susceptibility maps were developed, and the accuracy of the models was evaluated by a ranking system, based on the calculated area under the receiving operating characteristic curve (AUROC), mean absolute error, and mean square error (MSE) accuracy indices. According to the results, the GA-ANFIS with a total ranking score (TRS) = 24 presented the most accurate prediction, followed by PSO-ANFIS (TRS = 17), DE-ANFIS (TRS = 13), and ACO-ANFIS (TRS = 6). Due to the excellent results of this research, the developed landslide susceptibility maps can be applied for future planning and decision making of the related area
Evaluating urban housing development patterns in developing countries: Case study of Worn-out Urban Fabrics in Iran
The restoration of Worn-out Urban Fabrics (WoUFs), i.e., the disfiguration of fabric components of the city from their main shape, and the implementation of the urban housing development plan have always been pivotal activities for designing livable cities – especially in developing countries. Prior research, however, did not identify an appropriate model of sustainable housing development for the recovery of WoUFs. To fill this gap, housing development patterns – i.e., supportive housing, Mehr housing, rental, and social housing – aimed at restoring the WoUF of the Hemmatabad district in Isfahan city (Iran) were studied. Expert opinions, on the criteria affecting the selection of housing development patterns, from 40 professionals in urban management and urban development models were collected and then analyzed by the Analytic Hierarchical Process and VIKOR method. It resulted that, in order to revive the WoUF of Hemmatabad, social housing is the more desirable pattern of housing development (Qi = 1) compared to supportive housing (Qi = 0.911), Mehr housing (Qi = 0.117) and rental housing (Qi = 0.004). Results help governments of developing countries in directing their effort in the decision of which housing development pattern for WoUFs to implement
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