36 research outputs found

    A 3D benign paroxysmal positional vertigo model for study of otolith disease

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    AbstractObjectiveTo develop a three-dimensional study tool of the membranous labyrinth in order to study the pathophysiology, diagnostic workup and treatment of benign paroxysmal positional vertigo (BPPV). BPPV is the most common cause of peripheral vertigo. Its diagnosis and treatment depend on an understanding of the anatomy of the vestibular labyrinth and its position relative to the head. To date, many illustrations have been made to explain principals of diagnosis and treatment of BPPV, but few have been based on anatomical studies of the membranous labyrinth.MethodsA cadaveric human membranous labyrinth was axially sectioned at 20 μm resolution, stained and segmented to create a high-resolution digital model. The model was cloned to create an enantiomeric pair of labyrinths. These were associated a 3D model of a human skull, segmented from MRI data, and were oriented according to established anatomic norms. Canal markers representing otoliths were created to mark canalith position during movement of the model within the 3D environment.ResultsThe model allows visualization of true membranous labyrinth anatomy in both ears simultaneously. The dependent portion of each semicircular duct and of the utricle can easily be visualized in any head position. Moveable markers can mark the expected progress of otolith debris with changes in head position and images can be captured to document simulations. The model can be used to simulate pathology as well as diagnostic maneuvers and treatment procedures used for BPPV. The model has great potential as a teaching tool.ConclusionA simple model based on human anatomy has been created to allow careful study of BPPV pathophysiology and treatment. Going forward, this tool could offer insights that may lead to more accurate diagnosis and treatment of BPPV

    Scabies contamination status in Iran: A review

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    Background and aims: Scabies is a common worldwide parasitic contagious disease caused by Sarcoptes scabiei of the order of Astigmata of the family of Sarcoptidae. Therefore, this review is to determine the exact status of scabies in Iran in order to manage it better. Methods: On the whole, out of the 120 articles and books, 56 ones were covered based on items such as study purpose, date of publication, journal’s credibility, indication of the subject in them, transmittance, way of prevention, diagnosis, and treatment. Results: Due to the non-uniform geographical distribution of scabies in Iran, diagnosis and treatment of the disease is different. Studies show that scabies is on increase in Iran. Thus, scabies is a burden to the economy and the health care system. Prevalence of this disease has been rather high in Iran during war, prisons, and geographical humid areas which are variable in different provinces due to various climates. Conclusion: By regular monitoring and controlling the way the disease spreads, health of the population at risk can be maintained in order to bring health to the society that is among the main aims of every organizations and health providing institutions. This review focuses on scabies in Iran and other countries the entire world over to find ways for preventing and giving health care to control the diseas

    A High Payload Steganography Mechanism Based on Wavelet Packet Transformation and Neutrosophic Set

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    In this paper a steganographic method is proposed to improve the capacity of the hidden secret data and to provide an imperceptible stego-image quality. The proposed steganography algorithm is based on the wavelet packet decomposition (WPD) and neutrosophic set. First, an original image is decomposed into wavelet packet coefficients. Second, the generalized parent-child relationships of spatial orientation trees for wavelet packet decomposition are established among the wavelet packet subbands. An edge detector based on the neutrosophic set named (NSED) is then introduced and applied on a number of subbands. This leads to classify each wavelet packet tree into edge/non-edge tree to embed more secret bits into the coefficients in the edge tree than those in the non-edge tree. The embedding is done based on the least significant bit substitution scheme. Experimental results demonstrate that the proposed method achieves higher embedding capacity with better imperceptibility compared to the published steganographic methods

    A Comprehensive Look at Nitrogen and Phosphorus Use Efficiency in Saffron (Crocus Sativus L.)

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    Saffron (Crocus sativus L.) is an annual plant from a biological aspect, but it has a perennial cycle in the field conditions. Cytological impairments such as triploid and self-incompatibility mechanisms are considered as the most important reasons for male-sterility in saffron. Therefore, saffron reproduction is made by meristems tissues and establishment of new daughter corms which are produced by the mother corms. During the growing season, mother corms deteriorate gradually with increasing daughter corms growth. Each daughter corm is considered as a mother corm for replanting in the next growing season. Duo to the life cycle of saffron as a perennial plant in the field conditions, the gradual deterioration of mother corms during the growing season and also the remobilization of nitrogen and phosphorus from aerial part to daughter corms at the end of each growing season, the study of acquisition and use efficiency of nitrogen and phosphorus in saffron is more complicated than other annual or biannual plants. Firstly, the objective of this review article is to describe the nitrogen and phosphorus concentration in aerial parts and daughter corms in saffron. In addition, relevant literature related to the most important strategies for improving nitrogen and phosphorus use efficiency is reviewed. Secondly, the relationship between nitrogen and phosphorus use efficiency in saffron is discussed

    Effects of Corm Size, Organic Fertilizers, Fe-EDTA and Zn-EDTA Foliar Application on Nitrogen and Phosphorus Uptake of Saffron (<i>Crocus sativus</i> L.) in a Calcareous Soil under Greenhouse Conditions

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    A greenhouse research experiment was conducted. The experiment was arranged in factorial layout based on a completely randomized design. The mother corm size (0.1-4 g, 4.1-8 g and 8-12 g), organic fertilizers (cattle manure 15 t ha-1, vermicompost 10 t ha-1,chamomilecompost 10 t ha-1 and control) and micronutrients (Fe-EDTA and Zn-EDTA) in two levels (foliar application and no application) were assigned as the first, second and third experimental factors, respectively. Based on the results, with increasing mother corm size, formation of small corms (0.1-4 g) decreased, whereas the percentage of medium (4.1-8 g) or large size (more than 8 g) corms increased. The highest corm yield was observed when cattle manure was applied. Moreover, foliar application increased daughter corm yield in medium and larger size corms. Phosphorus and nitrogen concentration in daughter corms increased with increasing the size of mother corms. Organic fertilizers significantly increased phosphorus and nitrogen concentration in all size of corms: phosphorus content in large daughter corms increased five times on account of cattle manure application. Proper nutrient management during the first year of saffron propagation could improve corm number than rather corm weight

    Effects of Different Water Supply and Corm Planting Density on Crocin, Picrocrocin and Safranal, Nitrogen Uptake and Water Use Efficiency of Saffron Grown in Semi-Arid Region

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    Saffron’s color, taste and odor result from the chemicals crocin, picrocrocin and safranal, respectively. Hence, in addition to quantitative yield, secondary metabolites content are known as crucial factors for a successful saffron production. Moreover, enhancing resources efficiency, especially water and nitrogen, is becoming increasingly important for agricultural improvement in arid and semi-arid regions. Thus, the effects of irrigation levels and corm planting on crocin, picrocrocin and safranal content, water use efficiency (WUE) as well as nitrogen use efficiency (NUE) of saffron were investigated as a two-year field experiment based on a randomized complete block design arranged in split-plot with three replicates. The irrigation levels (100, 75 and 50% of saffron water requirement) and corm planting pattern (50, 100, 200 and 300 corms m-2) were allocated to main and sub-plots, respectively. Based on the results, crocin and picrocrocin content increased with decreasing irrigation levels. The highest WUES (WUE based on dry stigma yield) was obtained when 50% of saffron water requirement was supplied. However, the lowest WUEC (WUE based on daughter corms yield) and NUEC (NUE based on daughter corms yield) were obtained when 50% of saffron water requirement was applied. Irrespective of irrigation levels, WUES, WUEC and NUEC increased with increasing the planting density. The results demonstrated that although relatively severe water stress increases WUES and secondary metabolites in saffron stigmas, it could decrease WUEC and NUEC through affecting daughter corm growth

    Some reasons for saffron yield loss over the last 30 years period (Review Article)

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    Saffron (Crocus sativus L.) is a perennial plant which grows basically in arid and semi-arid regions of Iran. Despite saffron’s adaptation to these regions, the assessment of changes in cultivation area over the last 30 years reveals that cultivation of this crop has sharply increased. According to the available statistics, there are 21 provinces where saffron is cultivated on about 84,000 hectares of land. Nonetheless, saffron yield per unit area has aggressively fallen from 5.1 kg ha-1 in 1982 to 3.2 kg ha-1 in 2015. Saffron yield loss can be caused by several factors, such as mismanagement in agriculture section, economics and post-harvest processing as well as the recent droughts. Lack of attention to these factors could lead to further decline in saffron yield in the future. The saffron yield loss over the last 30 years is an alert for saffron-related institutions such as the universities, research centers and Agricultural Research, Education and Extension Organization (AREEO) to pay more attention to this crop and prepare more comprehensive programs. In developing these programs, the importance of government policies for planning and approving enough budget is to be highlighted. In this review, first we focus on the reasons for saffron yield loss during the last 30 years and then we try to provide some solutions in relation to these reasons

    Effect of corm planting density, organic and chemical fertilizers on formation and phosphorus uptake of saffron (Crocus sativus L.) replacement corms during phonological stages

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    Saffron (Crocus sativus L.) propagates by replacement corms producing from the mother corm after flowering during each season. In order to investigate the effect of corm planting density, organic and chemical fertilizers on formation and phosphorus uptake of saffron replacement corms during phonological stages, a field experiment was conducted as factorial layout based on randomized complete block design with three replications, at Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, during 2013 and 2014 growing seasons. The experimental treatments were all combination of different levels of planting density (25, 50, 75 and 100 corms per m2) and fertilizer sources (manure 25 t. ha-1, chemical fertilizer (N 150 kg ha-1 + P 75 kg ha-1) and control). Due to different sampling dates of replacement corms during phonological stages (21 November, 21 December, 20 January, 20 April and 21 May, respectively), the experimental data were analyzed as factorial - split in time based on a randomized complete block design. Based on results, the highest number of replacement corms lower than 4 g (5.8 corms per plant) were observed in fifth sampling stage and then decreased. In all levels of planting density (25 to 100 corms per m2), the effects of manure on increasing the number, weight and phosphorus content of replacement corms in range of 4.1 to 8 and 8.1 to 12 g per plant were significantly higher than chemical fertilizer. In fifth sampling stage, by applying the manure, the weight and phosphorus content of replacement corms in range of 8.1 to 12 g per plant were significantly increased (approximately twice), as compared to chemical fertilizer. It seems the decrease in saffron yield as result to decreasing the corm planting density can be slightly offset by increasing the percentage of larger corms formation per plant
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