Efficient filtration system for paraffin-catalyst slurry separation

The filtration efficiency for separating liquid paraffin (or water) from a slurry consisting of 25 weight% spherical alumina in a Slurry Bubble Column Reactor (SBCR) comprised of a cylindrical tube of 10 cm diameter and 150 cm length was studied. Various differential pressures (ΔP) were applied to two separate tubular sintered metal stainless steel filter elements with nominal pore size of 4 and 16μm. The experimental results disclosed that the rate of filtrations increased on applying higher differential pressure to the filter element. Albeit this phenomenon is limited to moderate ΔPs and for ΔP more than 1 bar is neither harmful nor helpful. The highest filtration rates at ΔPs higher than 1 bar were 170 and 248 ml/minute for 4 and 16μm respectively. Using water as the liquid in slurry the rate of filtration enhanced to 4 folds, and this issue reveals impact of viscosity on filtration efficiency clearly. In all situations, the total amount of particles present in the filtrate part never exceeded a few parts per million (ppm). The statistical analysis of the SEM image of the filtrate indicated that by applying higher pressure difference to the filter element the frequency percent of larger particle size increases. The operation of filter cake removing was performed with back flashing of 300 ml of clean liquid with pressures of 3-5 bar of N2 gas

Finite Element Analysis on Reinforced Concrete Columns Strengthened by ECC Jacketing under Eccentric Compressive Load

Engineered cementitious composite (ECC) can be used for strengthening of concrete columns due to its similar structure and suitable connection to normal concrete and its special tension behavior. In this study, to analyse the columns, finite element (FE) method was used after verification by experimental results. Reference column was strengthened by normal concrete and ECC jacketing. The effects of type of jacket material, longitudinal reinforcement, compressive stress and ultimate tensile strain of ECC on variations of eccentric load-bending moment (P-M) interaction curves were investigated. Results showed that the use of ECC instead of normal concrete can increase load carrying capacity of strengthened column, due to tensile strain hardening behavior of this material. It was found that, amount of this increase depends on eccentricity of eccentric load and varying from 0.4-23%. In ECC jacketing, tensile cracks are continuous, but in concrete jacketing, there were discrete cracks and more quantity of damages. Due to higher load carrying capacity and better distribution of tensile cracks in ECC jacketing than normal concrete jacketing, the use of ECC is suitable for strengthening of reinforced concrete columns. Load carrying capacity of columns under concentric load and pure bending moment were calculated by theoretical method and the results were compared with FE

Antimicrobial Effects of SeptiTurbo, Deconex (Solarsept) and 0.525% Sodium Hypochlorite Spray on Alginate Impression Materials

Objectives: Dental impressions are among the potentially infectious items in dentistry. Dental impressions are invariably contaminated with saliva or blood. Such fluids may contain viral or bacterial pathogens including Bacteroides, Fusobacterium, Porphyromonas and Prevotella. The aim of this study was to assess the effects of three different types of disinfectants on alginate impression materials after one, three and five minutes.Methods: In this in vitro experimental study, 126 circular samples of alginate impression materials were contaminated with Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa and were then disinfected with 0.525% sodium hypochlorite, Deconex (Solarsept) and SeptiTurbo spray. Afterwards, the samples were wrapped in moist paper towels and kept in plastic bags for one, three and five minutes. Number of bacterial colonies was counted 24 hours after incubation. Negative and positive controls were included.Results: After five minutes, 0.525% sodium hypochlorite showed the highest disinfection activity against S. aurous as it eradicated over 99.98% of the bacteria. Although the disinfecting agents showed non-significant results in eradicating S. aureus, SeptiTurbo was more effective in elimination of S. aurous . The disinfection activity of different agents increased with time.Conclusion: This study revealed that alginate can be effectively disinfected with SeptiTurbo and sodium hypochlorite by the spraying technique. This study highlighted the efficacy of SeptiTurbo for eradication of S. aurous

Two-stage Robust-Stochastic Electricity Market Clearing Considering Mobile Energy Storage in Rail transportation

This paper proposes a two-stage robust-stochastic framework to evaluate the effect of the battery-based energy storage transport (BEST) system in a day-ahead market-clearing model. The model integrates the energy market-clearing process with a train routing problem, where a time-space network is used to describe the limitations of the rail transport network (RTN). Likewise, a price-sensitive shiftable (PSS) demand bidding approach is applied to increase the flexibility of the power grid operation and reduce carbon emissions in the system. The main objective of the proposed model is to determine the optimal hourly location, charge/discharge scheduling of the BEST system, power dispatch of thermal units, flexible loads scheduling as well as finding the locational marginal price (LMP) considering the daily carbon emission limit of thermal units. The proposed two-stage framework allows the market operator to differentiate between the risk level of all existing uncertainties and achieve a more flexible decision-making model. The operator can modify the conservatism degree of the market-clearing using a non-probabilistic method based on info-gap decision theory (IGDT), to reduce the effect of wind power fluctuations in real-time. In contrast, a risk-neutral-based stochastic technique is used to meet power demand uncertainty. The results of the proposed mixed-integer linear programming (MILP) problem, confirm the potential of BEST and PSS demand in decreasing the LMP, line congestion, carbon emission, and daily operation cost

Circulating nesfatin-1 levels in women with polycystic ovary syndrome: A systematic review and meta-analysis

Background: Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder in females. Nesfatin-1 is a neuropeptide synthesized in the hypothalamus and other peripheral organs, and there are conflicting opinions about its correlation with PCOS. Objective: This study aims to investigate the correlation between nesfatin-1 and PCOS and evaluates the effectiveness of nesfatin-1 as a biomarker for the detection of PCOS in women. Materials and Methods: A systematic review and meta-analysis were conducted to identify pertinent articles from databases such as PubMed, Web of Science, Cochrane, EMBASE, Scopus, and Google Scholar. The standardized mean difference (SMD) and 95% confidence interval (CI) were calculated using a random effects model to compare group outcomes. Additionally, meta-regression and subgroup analysis were performed to elucidate sources of heterogeneity. Results: The meta-analysis involved 12 studies with 1222 participants, and the findings revealed a significant relationship between PCOS and nesfatin-1 levels. The pooled (SMD = 0.54; 95% CI: 0.00-1.07; p = 0.04) indicated a significant difference between the evaluated groups. Moreover, a subgroup analysis showed that there was a substantial difference in nesfatin-1 levels among women with PCOS and higher homeostatic model assessment for insulin resistance ratio (SMD = 1.46; 95% CI: 0.92-2.00; p < 0.001). Conclusion: Our meta-analysis indicates an association between high nesfatin-1 levels and PCOS. This suggests a potential role of nesfatin-1 in the development of PCOS and proposes it as a potential diagnostic biomarker for the disease. However, further research is necessary to validate these findings. Key words: Polycystic ovary syndrome, Insulin resistance, Body mass index, Meta-analysis

Evaluation of the effect of Kandovan propolis against Streptococcus Mutans

BACKGROUND AND AIM: In recent years, propolis has been introduced as one the most efficient agents against cariogenic bacteria. However, due to the lack of data on the propolis collected from Kandovan (Easthern Azarbaijan, Iran), this study was designed to investigate the effect of this type of propolis on Streptococcus mutans (S. mutans). METHODS: In this experimental study, the ethanolic extraction of propolis (EEP) was prepared with different concentrations (1%, 3%, 5%, and 10%) while the distilled water was incorporated as control. The antibacterial efficacy was tested via two standard methods including the agar disk diffusion and minimum inhibitory concentration (MIC) tests. Finally, the resulting data were analyzed using one-way analysis of variance (ANOVA) and Bonferroni post-hoc tests ( = 0.05). RESULTS: The obtained MIC was 2.5 mg/ml. However, in disk diffusion test, the 1% and 3% EEP solutions did not exhibit any zone of inhibition, however the 5% EEP showed very strong antibacterial effect (P < 0.001). CONCLUSION: The EEP extracted from Kandovan had significant antibacterial effect against S. mutans when prepared in 5% concentration. Therefore, this type of propolis could be considered as one of the most efficient propolis against S. mutans. KEYWORDS: Propolis; Streptococcus Mutans; Antibacteria

Two-Stage Robust-Stochastic Electricity Market Clearing Considering Mobile Energy Storage in Rail Transportation

This paper proposes a two-stage robust-stochastic framework to evaluate the effect of the battery-based energy storage transport (BEST) system in a day-ahead market-clearing model. The model integrates the energy market-clearing process with a train routing problem, where a time-space network is used to describe the limitations of the rail transport network (RTN). Likewise, a price-sensitive shiftable (PSS) demand bidding approach is applied to increase the flexibility of the power grid operation and reduce carbon emissions in the system. The main objective of the proposed model is to determine the optimal hourly location, charge/discharge scheduling of the BEST system, power dispatch of thermal units, flexible loads scheduling as well as finding the locational marginal price (LMP) considering the daily carbon emission limit of thermal units. The proposed two-stage framework allows the market operator to differentiate between the risk level of all existing uncertainties and achieve a more flexible decision-making model. The operator can modify the conservatism degree of the market-clearing using a non-probabilistic method based on info-gap decision theory (IGDT), to reduce the effect of wind power fluctuations in realtime. In contrast, a risk-neutral-based stochastic technique is used to meet power demand uncertainty. The results of the proposed mixed-integer linear programming (MILP) problem, confirm the potential of BEST and PSS demand in decreasing the LMP, line congestion, carbon emission, and daily operation cost

A systematic review of variables used to assess clinically acceptable alignment of unilateral transtibial amputees in the literature.

Prosthetic alignment is a subjective concept which lacks reliability. The outcome responsiveness to prosthetic alignment quality could help to improve subjective and instrument assisted prosthetic alignment. This study was aimed to review variables used to assess clinically acceptable alignment in the literature. The search was done in some databases including: Google Scholar, PubMed, EBSCO, EMBASE, ISI Web of Knowledge and Scopus. The first selection criterion was based on abstracts and titles to address the research questions of interest. The American Academy of Orthotics and Prosthetics checklists were used for paper risk of bias assessment. A total of 25 studies were included in this study. Twenty-four studies revealed the critics of standing position or walking to locate clinically acceptable alignment, only one study measured outcomes in both situations. A total of 253 adults with transtibial amputations and mean age of 48.71 years participated in included studies. The confidence level of included studies was low to moderate, and before-after trial was the most common study design (n = 19). The joint angle, load line location with respect to joints and center of pressure-related parameters were reported as sensitive outcomes to prosthetic alignment quality in standing posture. The amount of forces at various parts of gait cycle and time of events were sensitive to prosthetic alignment quality during walking. Standing balance and posture and temporal parameters of walking could help to locate clinically acceptable alignment.N/

Assessment of the Relationship Between Facial and Dental Midlines with Anatomical Landmarks of the Face and Oral Cavity

Objective:The purpose of the present study was to determine the facial anatomical landmarks, in order of accuracy, closest to the midline of the face, as well as oral cavity midline, and to specify which intraoral anatomical landmarks are closer to the dental midline.Methods:Three commonly used anatomical landmarks including nasion, nose, and philtrum tips were marked clinically in 108 subjects. A frontal full-face digital image was used for midline analysis in accordance with the esthetic frame. Deviations from the facial and oral midlines were measured for the three clinical landmarks. Dental midline was considered as the fourth landmark. Alginate impressions were taken, and casts were analyzed under standardized conditions. The labial frenum and incisive papilla were marked. Cast images were taken and analyzed.Results:Data showed difference between the mean ratios of the selected anatomical landmarks and the facial and oral midlines (p≤0/05). The anatomical landmark hierarchies, in proximity to the facial midline, are commissural midlines, nasion, philtrum tip, nose tip, and dental midline, respectively. The anatomical landmark hierarchies, in proximity to the commissural midline, include dental midline, philtrum tip, nose tip, and nasion. The labial frenum was less deviated from the dental midline than the incisive papilla.Conclusion:With respect to shortcomings, the results showed that all of the anatomical landmarks were deviated from the facial and oral midlines. The order of proximity of the anatomical landmarks to the facial midline was as follows: commissural midline, nasion, philtrum, and dental midline