Sand Dune Systems in Iran - Distribution and Activity.

Wind erosion and shifting sand dunes as a land degradation process is a serious problem in Iran. There are significant gaps in our knowledge of Iran sand dunes in national scale for the English speaking international scientific community as well as wind erosion and sand transport in Sistan plain. Identifying active dunes and monitoring areas with migrating sand are important prerequisites for mitigating these damages. In addition, wind erosion is one of the most serious problems in the Sistan region, located in the East of Iran and near the border of Afghanistan. This thesis has two major purposes: (1) to assess sand dune activity in national scale of Iran (2) to investigate wind regime and investigated spatial and temporal patterns of wind erosion process in Sistan region. With regard to first objective, the spatial variation of the wind energy environment based on the sand drift potential (DP), with using Fryberger and Dean's (1979) method, was calculated from 204 meteorological stations in and around Iran’s deserts. Three commonly dune activity models – the Lancaster mobility index (1988), the Tsoar mobility index (2005), and the index developed by Yizhaq et al. (2009) – were used for the evaluation of Iran’s sand dune activity. The analysis of the indices showed that the dunes activity was characterized by great spatial variations across Iran’s deserts. All three models identified fully active dunes in the Sistan plain, the whole of the Lut desert, as well as in the Zirkuh Qaien and Deyhook regions, while the dunes in the northern part of Rig Boland, Booshroyeh and in the Neyshabor dunefields were categorized as stabilized dunes. For other dunes, the models show a less unified activity classification, with the Lancaster and Yizhaq models having more similar results while the Tsoar model stands more apart. Overall the three models delivered comparable results in some instances and diverging results in others. The reasons for this are the use of different parameters and their impact on the model construction. The main contradictions of the three models results are revealed when the wind blows for only short times but with a high energy, like in the north of the Dasht-e Kavir desert (Damagan, Foromad) and at some stations in the wind of the 120 days’ domain (Sedeh Birjand). Field observation demonstrated that dunes in these areas are completely active, but the Lancaster mobility index (LMI) classified them as inactive or semi-active because of a low to moderate percentage of wind events above the transport threshold. At the same time the DP in this region showed high values and thus the Tsoar mobility index (TMI) classified the dunes as active, while the Yizhaq model (YMI) classified them as active or semi-active. In fact, in spite of high wind energy, the percentage of winds above threshold (W%), that is upper 12 knot or 6.2 m s-1 in this study, was rather low, as high speed winds only occur during the warm season, while the rest of the year is characterized by calm weather. The nature of the wind power parameter varies from the LMI, that is the percentage of winds above threshold (W%) to the TMI and YMI that is DP. DP reflects the quantity (frequency) and quality (intensity) of the wind power, but W% only shows its quantity (frequency of winds above the transport threshold). It seems that if DP was used in the LMI instead of W%, it would provide more favourable results . In addition, the statistical analysis (correlation coefficient) between DP values and the percentage of wind events above the transport threshold (%W) at the meteorological stations in the study area shows a moderate correlation. Based on this argumentation, W% has been replaced by the DP (vu) as the wind energy parameter in Lancaster mobility index (1988) and a Modified Lancaster Index (MLI) was developed. Based on these model results and fields observations, a modified Lancaster mobility index has been applied to show a more realistic spatial variation of sand dunes activity in Iran’s desert areas. With regard to second objective, the wind regime, formation of aeolian dunes and the rate of sand transport in Sistan and Registan were investigated. The Sistan region in eastern Iran and the Registan region in South-western Afghanistan are strongly influenced by the Sadobist Roozeh wind (the wind of the 120 days), which is blowing along the Iran-Afghanistan border from North to South, then shifts it’s direction toward the Southeast into the Sistan region and, finally, continues eastward into south-western Afghanistan, forming the Registan sand seas. It blows during the hot season due to the pressure gradient between the Turkmenistan High and the Pakistan Low. In order to determine the wind regime and the sand transport, wind roses based on long-term datasets from 16 meteorological stations, DP, the Resultant Drift Direction (RDD), the Resultant Drift Potential (RDP) and the RDP/DP ratio have been calculated using Fryberger and Dean's (1979) method. The distribution of the Registan sand dunes was surveyed by using Landsat ETM data, Google Earth scenes and field operations (the latter only in the Iranian part). The spatial differences of the drift potential were simulated using GIS and geostatistical methods overlaying the sand dune map. The results show that DP increases from north to south along the border between Iran and Afghanistan and reaches to highest values in the Sistan region, then decreases gradually in the Registan sand seas. The highest wind energy, based on DP matches, was determined exactly where the ephemeral lakes in the northern part of the Sistan plain are located, which function as a source area of intense dust and sand storms during the dry season. The annual DP calculated in Sistan is one of the highest values (2516 vector units) in inland desert and categorized it into the windiest desert in the world. The temporal trend of the DP showed an increase between 1999 and 2007, followed by a decrease until 2015 in Sistan. The results show that the wind regime in the Sistan and Registan regions is unimodal during the wind of 120 days (the Sadobist Roozeh) period, which is also supported by the dominance of transverse, barchanoid and barchans dunes in both regions . In continue second objective, we measured the rate of sediment transport in Hamoun-e Baringak, as one of the six ephemeral lakes, producing more aeolian sediment into the atmosphere in Sistan region. In order to investigate the land surface sensitivity to aeolian transport, 74 graduated pins were embedded randomly in the ephemeral Baringak Lake bed and the aeolian transport rates were measured for three events in 2013 individually as well as for the total study period. The spatial and temporal variation of the aeolian transport was also mapped using GIS and geostatistics methods for these events and for the total duration of 103 days. The resulting variogram revealed a high spatial dependence of the different events and showed that geostatistical techniques are a valid tool for the mapping of aeolian sediment transport. The average transport rate in terms of the detected drift height on the dry lake bed was 1.93 cm or 31 kg/m2 between the 5th of August and the 17th of November in 2013

URBANISM, URBAN MANAGEMENT AND DEVELOPMENT

Abstract. In today’s world, tourism known as one of the main factors of the global economy, it has asignificant role in the international equations process. At a same time has extensive impact on various aspects, planning and policy economic communities place the tourism on the top of the different agenda. Tourism industry is the most extensive service industry and count as the world’s most important job creation industry. Tourism pedestrian way is the main interface and link dynamic urban areas and tourists. In addition to economic and social role, it is a fundamental key factor in the urban tourism development and active presence of tourists in urban areas. The Shiraz city, especially the main central area and old urban texture (historic and cultural texture) and axis crossing the SANGE SIAH contains enormous tourism potential and capacity. it’s a cross axis for tourists and pilgrims, and a lot of people use the neighborhood mentioned above, considering that more special amenities for urban tourism required. This paper attemptto identify strengths and weaknesses of the mentioned path from the tourism standpoint using the SWOT method and to this end, scientific and practical strategic alternatives along with tourism development, presented.Keywords: Tourism pedestrian way, Urban tourism, Shiraz historical textures and SANGE SIAH axis

BLIND SOURCE SEPARATION USING MAXIMUM ENTROPY PDF ESTIMATION BASED ON FRACTIONAL MOMENTS

Abstract. Recovering a set of independent sources which are linearly mixed is the main task of the blind source separation. Utilizing different methods such as infomax principle, mutual information and maximum likelihood leads to simple iterative procedures such as natural gradient algorithms. These algorithms depend on a nonlinear function (known as score or activation function) of source distributions. Since there is no prior knowledge of source distributions, the optimality of the algorithms is based on the choice of a suitable parametric density model. In this paper, we propose an adaptive optimal score function based on the fractional moments of the sources. In order to obtain a parametric model for the source distributions, we use a few sampled fractional moments to construct the maximum entropy probability density function (PDF) estimation . By applying an optimization method we can obtain the optimal fractional moments that best fit the source distributions. Using the fractional moments (FM) instead of the integer moments causes the maximum entropy estimated PDF to converge to the true PDF much faster . The simulation results show that unlike the most previous proposed models for the nonlinear score function, which are limited to some sorts of source families such as sub-gaussian and super-gaussian or some forms of source distribution models such as generalized gaussian distribution, our new model achieves better results for every source signal without any prior assumption for its randomness behavior

Rolling up the pieces of a puzzle: A systematic review and meta-analysis of the prevalence of toxoplasmosis in Iran

Toxoplasmosis is a neglected parasitic disease with global distribution in warm-blooded vertebrates and high prevalence among different human societies. We contrived a systematic review and meta-analysis on the prevalence of toxoplasmosis in Iran. Following the general methodology recommended for systematic reviews and meta-analysis, four English and three Persian electronic databases were explored up to April 2016. Out of 105,139 examined samples of different hosts, the weighted overall prevalence was 37% (95% CI = 31–43). Due to the significant heterogeneity (I2 = 81.9%) the random-effects model was used. The pool estimated prevalence of toxoplasmosis in human intermediate hosts, animal intermediate hosts, and definitive hosts was 43% (95% CI = 38–47), 26 (95% CI = 17–35) and, 34% (95% CI = 22–46), respectively. Our results represent that regular inspection in food industries, improved screening programs using standard diagnostic assay as well as distinguishing toxoplasmosis condition in other zoonotic hosts are extremely recommended for better disease management in Iran.Keywords: Toxoplasma gondii, Prevalence, Iran, Systematic review, Meta-analysi

Quantifying Cortical Bone Free Water Using short echo time (STE-MRI) at 1.5T

Purpose: The purpose of our study was to use Dual-TR STE-MR protocol as a clinical tool for cortical bone free water quantification at 1.5T and validate it by comparing the obtained results (MR-derived results) with dehydration results. Methods: Human studies were compliant with HIPPA and were approved by the institutional review board. Short Echo Time (STE) MR imaging with different Repetition Times (TRs) was used for quantification of cortical bone free water T1 (T1free) and concentration (\r{ho}free). The proposed strategy was compared with the dehydration technique in seven bovine cortical bone samples. The agreement between the two methods was quantified by using Bland and Altman analysis. Then we applied the technique on a cross-sectional population of thirty healthy volunteers (18F/12M) and examined the association of the biomarkers with age. Results: The mean values of \r{ho}free for bovine cortical bone specimens were quantified as 4.37% and 5.34% by using STE-MR and dehydration techniques, respectively. The Bland and Altman analysis showed good agreement between the two methods along with the suggestion of 0.99% bias between them. Strong correlations were also reported between \r{ho}free (r2 = 0.62) and T1free and age (r2 = 0.8). The reproducibility of the method, evaluated in eight subjects, yielded an intra-class correlation of 0.95. Conclusion: STE-MR imaging with dual-TR strategy is a clinical solution for quantifying cortical bone \r{ho}free and T1free

Investigation of Three-Dimensional Axisymmetric Unsteady Stagnation-Point Flow and Heat Transfer Impinging on an Accelerated Flat Plate

General formulation and solution of Navier-Stokes and energy equations are sought in the study of threedimensional axisymmetric unsteady stagnation-point flow and heat transfer impinging on a flat plate when the plate is moving with variable velocity and acceleration towards the main stream or away from it. As an application, among others, this accelerated plate can be assumed as a solidification front which is being formed with variable velocity. An external fluid, along z - direction, with strain rate a impinges on this flat plate and produces an unsteady three-dimensional axisymmetric flow in which the plate moves along z direction with variable velocity and acceleration in general. A reduction of Navier-Stokes and energy equations is obtained by use of appropriate similarity transformations, for the first time. The obtained ordinary differential equations are solved by using finite-difference numerical techniques. Velocity and pressure profiles along with temperature profiles are presented for different examples of the plate velocity functions and selected Prandtl numbers. According to the results obtained, the velocity and thermal boundary layers feel the effect of variations of the plate velocity more than the plate acceleration. It means that the minimum boundary layer thickness happens at the maximum value of the plate velocity and acceleration effect plays a secondary role

Outcome of Patients Underwent Emergency Department Thoracotomy and Its Predictive Factors

Introduction: Emergency department thoracotomy (EDT) may serve as the last survival chance for patients who arrive at hospital in extremis. It is considered as an effective tool for improvement of traumatic patients’ outcome. The present study was done with the goal of assessing the outcome of patients who underwent EDT and its predictive factors. Methods: In the present study, medical charts of 50 retrospective and 8 prospective cases underwent emergency department thoracotomy (EDT) were reviewed during November 2011 to June 2013. Comparisons between survived and died patients were performed by Mann-Whitney U test and the predictive factors of EDT outcome were measured using multivariate logistic regression analysis. P < 0.05 considered statistically significant. Results: Fifty eight cases of EDT were enrolled (86.2% male). The mean age of patients was 43.27±19.85 years with the range of 18-85. The mean time duration of CPR was recorded as 37.12±12.49 minutes. Eleven cases (19%) were alive to be transported to OR (defined as ED survived). The mean time of survival in ED survived patients was 223.5±450.8 hours. More than 24 hours survival rate (late survived) was 6.9% (4 cases). Only one case (1.7%) survived to discharge from hospital (mortality rate=98.3%). There were only a significant relation between ED survival and SBP, GCS, CPR duration, and chest trauma (p=0.04). The results demonstrated that initial SBP lower than 80 mmHg (OR=1.03, 95% CI: 1.001-1.05, p=0.04) and presence of chest trauma (OR=2.6, 95% CI: 1.75-3.16, p=0.02) were independent predictive factors of EDT mortality. Conclusion: The findings of the present study showed that the survival rate of trauma patients underwent EDT was 1.7%. In addition, it was defined that falling systolic blood pressure below 80 mmHg and blunt trauma of chest are independent factors that along with poor outcome

Identification of land sensitivity to wind erosion using field data in Hamoun-e Baringak, Sistan

This study provides an applied method to estimate the land sensitivity of wind erosion in the Hamoun-e Baringak Sistan, as an ephemeral lake. Due to the wide extent of the sources of dust and sand production in Sistan, finding areas that are prone to wind erosion is of paramount importance in prioritizing stabilization. For this purpose, indices of transport rate (erodibility), soil shear strength, and SAVI were conducted.  To investigate the land erodibility to aeolian transport, 74 graduated pins were embedded randomly in the ephemeral Baringak Lake bed and the aeolian transport rates were measured for the total study period. The shear strength of the soil surface was measured using Torvane. The vegetation canopy density was extracted from digital images using the SAVI index. The results showed that there is a very significant relationship (1%) between soil shear strength and SAVI indices with transport rates. It means that this proposed method may be also applied to estimate land sensitivity in environments instead of threshold friction velocity of wind erosion in the field. Comparison of the results of regression model estimation with transport rates in the field were significant

Potential Risk Factors of Death in Multiple Trauma Patients

Introduction: Trauma has been recognized as one of the leading causes of death in many countries for decades. Reduction in mortality and morbidity rate of trauma cases is one of the most important attitudes in this field. Evaluation of different risk factors have been considered as the main goal of some studies. The purpose of this study was determining potential risk factors of death in trauma patients. Method: In a retrograde study, data of 740 patients admitted during three years (2009-2011) were studied. Demographic data (sex and age), clinical factors (blood pressure, pulse rate, respiratory rate, Glasgow coma scale (GCS)), trauma characteristics (location, type of injury, etc.), as well as outcome of patients were evaluated. Data analyses was done using SPSS 18.0. Stepwise multivariate regression analysis was used for recognition of independent predictive factors of death in multiple trauma patients. Results: Of those admitted, majority of patients were male (81.4%), 68% between 18 to 60 years, and 11.2% of them died during the course of treatment. Age; type of trauma; abnormal respiration rate, pulse rate, blood pressure; total GCS ≤8; abnormal pupil size; and head and neck; vertebral, and extremities fractures were obtained as significant predictive factor of death. GCS≤8, head and neck fracture, and abnormal pulse rate were independent death predictors. Conclusion: We identified GCS≤8, head and neck fracture, and abnormal pulse rate as predictive factors of mortality after trauma, which remained independent in the presence of all other factors and potentially treatable