27 research outputs found
Analysis of the Urban Water Requisition Demand for the Purpose of Re-engineering and Water Network Optimization (Case Study: Tabriz' Eram Urban Area)
Water shortage is one of the most important challenges of this century and it would be a serious obstacle for the mankind. In the near future, drinking water supply and water resources management will be at the forefront of planning for urban managers, which is becoming a crisis due to the serious shortage of water resources. This problem is more critical in country of Iran, where water depletion is now receiving serious attention. Different water management programs have been started by government to conserve and manage water more efficiently, especially in some critical areas such as Tabriz megacity located in North East of the country. Eram town is one of the problematic areas of Tabriz. Hence, in this study, we tried to do reengineering for this town to offer some solutions for the problems related with water supplying of the implemented network in this region. Regarding this issue, the GIS (Geographic information system) data of the available water supply network was used and the collected field data such as consumption rates in current conditions were applied to the network. Then the calibration of model was performed. Eram Town water distribution network reengineering has been performed considering a 2043 plan, taking into account population growth and the increase in consumption. In conclusion, it is suggested that, the network will perform more efficiently by adding new pipes or modifying the existing pipes. Also, the problem of lack of pressure in some parts of the network which cannot fulfill the requirements of subscribers at peak water usage hours, could be solved
Nutrition in Pediatric Nephrotic Syndrome
Nephrotic Syndrome is a collection of symptoms due to glomerular damage, characterized by proteinuria ≥3.5g/day or a protein-creatinine ratio ≥2. From an etiological point of view, there are three forms of nephrotic syndrome, including congenital, primary, and secondary. The first sign of the disease is periorbital edema, especially in the morning. Diagnostic confirmation is done through evaluation of urine protein, serum electrolytes, BUN, Cr, Albumin, and cholesterol. The main treatment goals of nephrotic syndrome are decreasing proteinuria, preventing complications, and protecting the renal function via appropriate drugs and diet.The main objective of this study was to review diets required in nephrotic syndrome in children: Protein at a diose of 0.8 mg/kg/day is the most effective diet in nephrotic patients. Low-fat diets (calorie intake <30% and cholesterol ≤200mg/day) can improve hyperlipidemia. Salt and water intake should be restricted in the range of less than 2 gr/day and 1-1.5 liters/day, respectively. Nephrotic syndrome patients have iron, copper, zinc, and calcium deficiency due to increased urine protein excretion or concomitant metabolic disorders. Keywords: Nephrotic syndrome; Diet; Pediatrics; Nutrition.Â
Significance of physicochemical factors in the transmission of Escherichia coli and chloride
Background: Organic manures are the source of many pathogenic bacteria which could be dangerous
for human health. Bacterial transmission and retention in soil is important for processes ranging
from contaminant degradation during in situ bioremediation to transport of pathogenic bacteria into
groundwater.
Methods: The aim of this study was to evaluate the transport of Escherichia coli and chloride (Cl) in the
soil saturation conditions, considering the importance of preferential flow using synthetic macrospores
(different diameters of macrospores including 0, 1 and 2 cm) and HYDRUS-2D model. Also, the
effect of different salinity levels of water (including electrical conductivity of 1, 2 and 4 dSm-1) on the
transmission of E. coli was investigated. The preferential flow system was prepared and designed using
two sand sizes including fine sand and coarse sands in the columns.
Results: The results showed that the retention of E. coli increased with the ionic strength of the solution,
while the effect of E. coli in the fine sand was greater than that of the coarse sand. This bacterial transfer
behavior was well described by numerical simulations. The importance of preferential flow in bacterial
transfer showed that it increases at higher ionic strength, even if overall transmission is reduced.
Although the bacterial transmission is facilitated in salinity, the results of this study showed that with
increase of ionic strength of the soil solution, the amount of bacterial purification was increased that
could be effective in controlling groundwater contamination with saline water management.
Conclusion: According to the results, with increase of ionic strength of the soil solution, the amount of
bacterial purification was increased that could be effective in controlling groundwater contamination
with saline water management, so that the least transition has taken place and the conditions for the
use of unconventional water sources were also created, without the environmental problem of the risk
of groundwater pollution.
Keywords: Escherichia coli, Soil, Water pollutio
Steel bridges structural health monitoring based on operational modal analysis accommodating evaluation of uncertainty
Structural damage detection is based on that the dynamic response of structure will change because of damage. Hence, it is possible to estimate the location and severity of damage leads to changes in the dynamic response before and after the damage. In this study, the genetic fuzzy system has been used for bridge structural health monitoring. A key objective of using genetic algorithms is to automate the design of fuzzy systems. This method is used for damage detection of a single span railway bridge with steel girders and a concrete bridge. For studying damage detection, the numerical models of these two bridges are built with the measured dynamic characteristics. A three-dimensional finite element model and a single two-dimensional girders model of the bridge have been constructed to study usefulness of the genetic fuzzy system for damage detection and the effectiveness of modeling. After analysis to control the uncertainties, the measured frequencies are contaminated with some noise and the effect of that on the achievement of damage detection method is evaluated. The present study has shown that the natural frequency has appropriate sensitivity to different damage scenarios in the structure. In addition, the natural frequency in comparison with other modal parameters, is less affected by random noise. Increasing the number of measurement modes and using torsional modes, will lead to an accurate damage diagnosis even in symmetrical structures
Damage Parameter Variations of Breakwater along with a Floating Wave Barrier and a Submerged Obstacle
Damage to rubble mound breakwaters (RMBs), both general and partial, causes instability and inconstancy of the structure against waves. This study aimed to investigate the effect of a submerged obstacle on the stability and damage reduction of RMBs as an innovative method and determine the optimal distance of the obstacle from the breakwater and the floating wave barrier based on the damage parameter. The waves affecting the breakwater were assumed to be random using a JONSWAP spectrum. The aggregates' movement and the RMB's exact deformation were recorded using close-range photogrammetric imaging, and the eroded area and the damage parameters were obtained at equal distances in eight cross-sections. According to the results of the tests, by analyzing the effect of the number of waves hitting the breakwater, 3000 waves were considered to bring the structure to a stable state. The results showed that increasing the relative wave height from 0.36 to 0.48 and from 0.48 to 0.6 increased the damage parameters to 39.12% and 44.44%, respectively, and increasing the relative wave period from 0.6 to 0.8 and 0.8 to 1 increased the damage parameters to 22.94% and 28.26%, respectively. Moreover, using a seaward obstacle at 0, 5, 10, 15, and 20 cm distances decreased the damage parameter. The greatest effect, a reduction of 39.15% in the damage parameter, was observed at a distance of 5 cm from the RMB. This number was reduced to 0.735 when a floating wave barrier was used without a submerged obstacle (i.e., 34.14%). Using an obstacle at 5 cm in conjunction with a wave barrier reduced the damage parameter by 54.03% and demonstrated the best function among different models. Hence, this model is proposed based on the experiments carried out in this study
Blocking natural killer cells in testicular torsion may prevent autoimmunity against low expressing major histocompatibility complex class I germ cells
Enhancing Concrete Properties Using Silica Fume: Optimized Mix Design
In the current work, concrete mixes containing (7.0-33.11) weight % silica fume as a partial replacement of cement with a water /cement ratio (0.42-0.48) were prepared according to an adopted two factorial central composite design. The samples were tested, optimized, and modeled for compressive strength and density. The estimated results confirmed that compressive strength and density increase with increasing silica fume content up to 11.9 wt.%. Response surface analysis results confirmed that silica fume concrete with developed compressive strength (53.42 MPa) could be prepared by incorporation of 11.9 wt. % silica fume as partial replacement of cement using 0.42 water/cement ratio. An increase in compressive strength and density (up to 39.3% and 2.6% ) respectively was recorded for silica fume concrete mixes compared to Portland cement concrete. Overall, the research findings revealed that silica fume concretes prepared with appropriate silica fume content and water/cement ratio exhibited superior strength and density characteristics candidate them to be used effectively in civil engineering applications
High risk individuals in COVID-19 pandemic; an updated review
In December 2019, cases of pneumonia with an unknown pathogen were reporting in Wuhan city, China. The World Health Organization (WHO) recognized it as a pandemic, on March 11, 2020. The most frequent site of involvement is the respiratory system. The most common symptoms include cough, fatigue and fever. In some cases, neurological, respiratory and gastrointestinal complications can lead to death. Inflammatory cytokines can play a major role in pathogen damage. Due to the pandemic of COVID-19 and its severe complications, it is critical to identify the high-risk groups. Since this disease has a rapid transmission, following the instructions announced by the WHO, prevention is vital, especially in people with risk factors for disease complications and mortality. According to the latest reports by CDC (Center for Disease Control and Prevention), older age and having some medical conditions such as smoking, obesity (BMI >= 30 kg/m(2)), chronic obstructive pulmonary disease (COPD), heart disease, cancer, solid organ transplant, type 2 diabetes mellitus, chronic renal failure, and sickle cell anemia in younger adults are known disease severity risk factor
Factorial Mixture Design for Properties Optimization and Modeling of Concrete Composites Incorporated with Acetates as Admixtures
Nowadays, admixtures are used with the aim to provide strength and durability to concrete with less water use. New and low-cost admixtures gained a large amount of consideration to mitigate the problems associated with concrete’s durability and service life without upsetting its strength properties. The current work investigates the effect of three types of acetates on the workability, density, and compressive strength of concrete, which is used in structures of the Iraqi ports that suffer from corrosion damages and deterioration owing to the aggressive marine environments. Potassium acetate (KA), calcium acetate (CaA), and ethyl acetate (EA) are incorporated with different doses (1.38–5.6 wt.% of cement) in concrete mixtures using different water/cement ratios (0.48–0.54) based on an espoused central composite experimental design. The experimental results confirmed that the average workability increased with increasing the acetate dose, particularly with CaA. The density and compressive strength of 28 days of water-cured mixtures increased with increasing acetate dose following the order: Ca > K > Ethyl acetate and decreased with increasing w/c ratio. The high rise in compressive strength and workability linked to control mixtures was 30.8% and 77.3% as well as 15.7% and 64.3% for the mixtures incorporated with 5.6 wt.% CaA and KA, respectively. While it was 14.2% and 58.3% for the mixtures incorporated with 3.5 wt.% EA. RSM was employed to optimize and model the design and hardened properties of concrete mixtures. ANOVA results predicted the same trend, which was obtained from the experimental results. The mathematical models were valued with high-regression coefficients. The highest compressive strength of 42.68 MPa has been achieved for a concrete mixture of 0.48 w/c ratio by the incorporation of 5.1 wt.% CaA through a model with R2 96.97%. The relatively low-cost acetate admixtures, particularly CaA, seemed promising for the fabrication of concrete with outstanding properties