Search

The investigation of the adsorption potential of the Jordanian calcinated bentonite to remove phosphate ions from aqueous solutions whether they are synthetic or actual samples was studied in this article, The temperatures for calcination ranged from (100°C-900°C). The effectiveness of calcining bentonite's ability to remove phosphate ions was investigated under various conditions, including initial concentration of phosphate ions, calcinations, temperature, particle size, pH levels, adsorbent dose, and contact time. Using pseudo-first-order, pseudo-second-order rates and intraparticle diffusion models the kinetic studies were carried out. The R² values indicated that pseudo-secondorder rather than pseudo-first-order provided a better fit for the phosphate transport. The activation energy for the removal for both synthetic and actual materials was computed, and it was found to be 8.93 and 12.120 kJ/mol, respectively, this shows that physisorption may have happened. The rate of phosphate ion uptake was also investigated using intraparticle diffusion model at different variables (temperature, particle size, agitation, and pH values), and both particle diffusion (Dp) and film diffusion (Df) coefficients were predicted, with the results indicating that film diffusion (Df) is the rate determining step. [ABSTRACT FROM AUTHOR]

Many efforts have been devoted to increase the efficiency of Savonius wind turbine in the past decade. But, researchers didn't consider the possible increment in the fluctuation amplitude of the exerted force on the rotor, which decrease the lifetime of the machine. The present study focuses on investigating the force fluctuation as well as the power generation enhancement of the two side-by-side Savonius rotors. A numerical method is used to compute the details of the flow field. Effects of the distance and tip speed ratio on the power generation and fluctuations of the exerted forces are studied at two phase differences between the rotor rotations. Obtained results show that the power generation enhancement may lead to increase in the fluctuation amplitudes of the exerted forces. The overall performance index indicating the ratio of the power generation enhancement to the total increment in the force fluctuation, shows that the optimum performance can be taken place when the distance between the rotors is twice the rotor diameter, when rotating without phase difference at the tip speed ratio of 1.0. • Numerical method is used to assess the effect of the distance between two Savonius rotors on the power generation and force fluctuation. • Power generation may enhance when distance between the rotors decreases. • Force fluctuations of two rotors as well as their power generations are not the same. • The power enhancement of the system is often associated with increasing the force fluctuation. • The overall optimum performance is achieved when the distance between the rotors' axes is twice the rotor diameter. [ABSTRACT FROM AUTHOR]

Background Venous thromboembolism (VTE) is a feared complication after bariatric surgery. Biliopancreatic diversion with duodenal switch (BPD-DS) is a complex bariatric procedure that is offered typically to super morbidly obese patients. Scarce data exist in reporting VTE outcome and identifying the risk factors associated with it after BPD-DS. Objective To determine the risk factors for VTE after BPD-DS at 90-day follow-up. Setting A nonprofit regional referral center and teaching hospital in Pennsylvania. Methods A retrospective chart review was performed on prospectively collected data over 10 years, between January 1, 2006 and December 31, 2016. Patients who underwent laparoscopic or robotic BPD-DS were included. Preoperative variables, selected risk factors, and methods of VTE prophylaxis were analyzed. Results A total of 662 patients who underwent BPD-DS were identified. The mean age was 44.7 ± 10.4 (20–72) years; 474 patients were female (71.7%), and the mean body mass index of the cohort was 50.5 ± 7.5 (34–98) kg/m 2 . Overall, 16 patients (2.4%) experienced VTE complication at 90-days follow-up post–BPD-DS with 100% follow-up rate; deep vein thrombosis was experienced by 10 patients (1.5%), and 6 patients (0.9%) experienced pulmonary embolism (1 patient experience both). None of those patients had a previous history of VTE. Only operative time ( P value = .009) and length of stay ( P value ≤ .001) were associated with VTE events. Other factors such as age, sex, body mass index, previous history of VTE, preoperative heparin injection, preoperative inferior vena cava filter insertion, intermittent compressive device use, interval heparin time, and postoperative chemical prophylaxis did not show a statistical association. A logistic regression analysis showed a statistically significant increase of VTE outcome with length of stay; odds ratio of 1.161, (95% confidence interval, 1.048–1.285), P value = .004. Conclusion With proper preoperative evaluation and aggressive VTE prophylaxis protocol, the risk of VTE post–BPD-DS is comparable to other bariatric procedures. Every effort should be adopted to shorten the length of stay, and thus reduce VTE risk. [ABSTRACT FROM AUTHOR]

Introduction Weight regain after Roux-en-Y gastric bypass (RYGB) is a frustrating long-term complication in some patients. Revision of RYGB to biliopancreatic diversion with duodenal switch (BPD-DS) is an appealing option. There is a paucity of information in literature regarding this type of conversion. Setting Regional referral center and teaching hospital, Pennsylvania, United States; nonprofit. Methods Between 2013 and 2016, a retrospective chart review was performed on all our revision cases. Patients who underwent conversion from RYGB to BPD-DS were selected and analyzed. Results Conversion from RYGB to BPD-DS was performed on 9 patients (8 females, 1 male; mean age: 49.2±7.6 [36–61] years). The mean body mass index (BMI) before the initial RYGB was 54.2±14.2 (36.2–79) kg/m 2 . The lowest mean BMI reached before conversion was 33.9±6.2 (27.9–43.3) kg/m 2 before it increased to 45.6±8.7 (28.8–60.2) corresponding to excess weight loss (EWL) of 33.1%±17.7% (10.6%–68.1%), before conversion. The average operative time was 402.6±65.8 (328–515) minutes for 1-stage conversions. No morbidities, reoperation, or readmission over 30 days postoperatively were reported. No leaks or mortalities were identified. The mean duration of follow-up postconversion is 16.3±13.6 (3–42) months. After conversion surgery, the mean BMI was 35.8±8.2 (27.6–49.5) kg/m 2 , while mean EWL loss was 64.1%±18.8% (45.9%–88.7%). The BMI of the cohort decreased by a mean of 9.8±5.1 (0.5–16.8) and the EWL increased by 31%±23.1% (4%–76.6%). Conclusion Our results indicate that conversion of failed RYGB to BPD-DS is laparoscopically or robotically safe and effective. A large cohort study with long-term follow-up is necessary to further assess the safety and efficacy of this method. [ABSTRACT FROM AUTHOR]

In this paper, a novel methodology is presented to evaluate the micro-grids reliability concerning the dynamic thermal aging failure of transformers. The widespread presence of distributed generation (DG) units reduces the loading passing through the distribution transformers and consequently improves the dynamic thermal failures. The system reliability is investigated for various penetrations of different scenarios from the view of DG technologies. The introduced method is applied to a realistic distribution system comprising different distribution transformers in Iran. The sensitivity analysis corresponding to adequacy indices such as expected energy not-supplied (EENS) based on DG penetrations is performed. By the use of the novel methodology proposed, it is possible to recognize how different DG technologies and penetrations can impact on the system reliability. The results demonstrate that the diesel generators and hybrid systems including diesel generators, photovoltaic units, and wind turbines are the most promising DG technologies to improve the transformer failures and the reliability of micro-grids compared with renewable DG units. [ABSTRACT FROM AUTHOR]

Genome-wide association studies (GWASs) show that genetic factors contribute to the risk of severe coronavirus disease 2019 (COVID-19) and blood analyte levels. Here, we utilize GWAS summary statistics to study the shared genetic influences (pleiotropy) between severe COVID-19 and 344 blood analytes at the genome, gene, and single-nucleotide polymorphism (SNP) levels. Our pleiotropy analyses genetically link blood levels of 71 analytes to severe COVID-19 in at least one of the three levels of investigation—suggesting shared biological mechanisms or causal relationships. Six analytes (alanine aminotransferase, alkaline phosphatase, apolipoprotein B, C-reactive protein, triglycerides, and urate) display evidence of pleiotropy with severe COVID-19 at all three levels. Causality analyses indicate that higher triglycerides levels causally increase the risk of severe COVID-19, thereby providing important support for the use of lipid-lowering drugs such as statins and fibrates to prevent severe COVID-19. [Display omitted] • Genetic analyses identify pleiotropy between blood analytes and severe COVID-19 • The identified pleiotropies suggest biological or causal relationships • Blood triglycerides have widespread shared genetic influences with severe COVID-19 • Higher levels of blood triglycerides might increase risk of severe COVID-19 Genetic factors contribute to severe COVID-19 and blood analyte levels. Tanha et al. identify blood analytes associated with the risk of severe COVID-19. The results suggest a strong genetic relationship between higher levels of blood triglycerides and risk of severe COVID-19. [ABSTRACT FROM AUTHOR]

Background Injury to thoracic duct is a rare potential complication of time-honored conventional thyroidectomy. Nevertheless, it can be a cause of significant morbidity, and sometimes life-threatening. Patient findings A 78-year-old female patient with a previous surgical history of thyroid lobectomy for nodular disease presented with primary hyperparathyroidism, and a nodule in the remaining thyroid lobe. The patient underwent completion thyroidectomy and parathyroidectomy. Less than 24 h post operatively, the patient developed progressive shortness of breath and neck swelling requiring immediate intubation and re-exploration. A large amount of chyle was drained and an injured thoracic duct was identified and ligated. Summary In experienced hands thyroid surgery is safe. Nevertheless, factors such as the type of pathology and its extent, the level of surgery, and re-operative surgery increase the risk of postoperative complications. Immediate surgical exploration is necessary when patients present with neck swelling and respiratory distress. In our case, a high output chyle leak in a confined space was life threatening. Conclusion Timely re-exploration following thyroid surgery and thorough knowledge of the anatomy of neck structures is crucial in sparing patients potential morbidity and/or mortality. [ABSTRACT FROM AUTHOR]

INTRODUCTION Gastric glomus tumors are fairly uncommon and mostly benign, with an estimated incidence of 1% of all GI soft tissue tumors. The most common GI site of involvement is the stomach, and in particular the antrum. Some cases have been discovered incidentally, but most are symptomatic presenting with GI bleeding, perforation or abdominal pain. Glomus tumors are submucosal tumors and hence mistaken with the more frequent gastrointestinal stromal tumors. PRESENTATION OF CASE A 33-year-old woman presented with intermittent dull upper abdominal pain for two days. Abdominal computed tomography (CT) was performed showing a hyperdense mass in the antrum. Endoscopy and endoscopic ultrasound revealed a submucosal antral mass along the greater curvature, suspicious for a gastrointestinal (GI) stromal tumor (GIST), a laparoscopic antrectomy with Billroth I reconstruction was done. Pathological examination revealed that the mass was a gastric glomus tumor. DISCUSSION The presented case report met all the usual standard criteria commonly used to identify glomus tumors, the uniqueness of the case lies in the occurrence of the glomus tumor in the stomach, first suspected as GIST, then confirmed as a gastric glomus tumor. The vast majority of glomus tumors of the GI tract have been described in the gastric antrum. They occur in adults of all ages with a significant female predominance (78%). CONCLUSION This case may aid in improving the recognition and diagnosis of this rare entity and in differentiating it from more common GISTs and gastric carcinoids. A built up knowledge between physicians is extremely necessary to avoid common confusion in taking the right medical approach. [ABSTRACT FROM AUTHOR]

• This paper introduces a novel method to reveal the effects of various CNCs on the failure probability of transformers. • TLBO algorithm and MCS are used to implement the proposed optimization method. • This paper illustrates the importance of proper cyber graph selection in the future conditions of the power network. Transformers as one of the valuable assets of the power system, have a remarkable role in the power system stability. Understanding the effective parameters on the transformer's failure is so vital to reduce the transformer outages. On the other hand, with improvement and extension of intelligent systems, identifying the effective parameters on the security of smart networks is of considerable importance. This paper clarifies the relation between the cyber network configuration (CNC) and the failure probability of transformers due to the distributed generator controller. Also, a novel method is proposed to determine the effects of various cyber network configurations on the failure probability of transformers and also select the best CNC to maximize the reliability of the cyber-physical system. Optimized configuration should maximize the data connection between cyber elements, particularly cyber elements that have cyber-power interdependency with the critical transformers in the power network. Results indicate that the improper CNCs can increase the failure probability of transformers and consequently it leads to increment of expected energy not supplied (EENS) of the power system. The proposed method is implemented on the real pilot power test system. [ABSTRACT FROM AUTHOR]

The performance of a solar still with different size sponge cubes placed in the basin was studied experimentally. The increase in distillate production of the still ranged from 18% to 273% compared to an identical still without sponge cubes under the same conditions. The effects of sponge cube size, percent volume of sponge, water depth, water salinity and the use of black coal and black steel cubes were also investigated. The study showed that the daily production of such a still can be greatly enhanced using sponge cubes. [Copyright &y& Elsevier]

• Mesenteric cystic lymphangiomas are rare benign lesions characterized by lymphatic vessels malformation with an unknown etiology. • Although, mesenteric cystic lymphangiomas are rare but should be included in the differential diagnosis of abdominal pain. • Surgical resection of mesenteric lymphangiomas should be performed as fast as possible to avoid many serios complications. Mesenteric cystic lymphangiomas are rare benign lesions of the abdominal cavity characterized by lymphatic vessels malformation with an unknown etiology. Despite the silent clinical course of mesenteric cystic lymphangiomas, they are considered as clinically tricky lesions with an immense spectrum of presentations. We present a case of abdominal mesenteric cystic lymphangioma in a 1-year 9-month-old female patient, who complained of fever and abdominal pain for 10 days duration. Laboratory investigations, abdominal X-ray, ultrasonography, computed tomography and histopathological examination were all used to establish the diagnosis. A trial of true-cut biopsies performed by an interventional radiologist was not informative, so a multidisciplinary team decision was made to excise the mass. Intraoperative findings include multiloculated fused cystic lesion (8.0 × 5.0 × 4.0 cm) on the descending mesocolon. Histopathological examination revealed the diagnosis of a mesenteric cystic lymphangioma. The postoperative period was not complicated. Mesenteric cystic lymphangiomas are mostly asymptomatic in nature, yet predisposed to life threating events. Surgical excision is the modality of treatment characterized by low recurrence rate and a non-complicated postoperative period. [ABSTRACT FROM AUTHOR]

Background: Common bile duct exploration (CBDE) is an available option in the management of choledocholithiasis. We aimed to analyze outcomes comparing laparoscopic and open approaches to CBDE using the American College of Surgeons (ACS) NSQIP database.Study Design: This was a retrospective cohort study of patients undergoing CBDE between 2008 and 2013, using the ACS NSQIP database. The cohort was split into 2 groups and compared based on operative approach: laparoscopic vs open CBDE.Results: There were 2,635 patients who underwent CBDE during the study period, and 52% underwent an open approach. After adjusting for all confounding variables, open CBDE was associated with a statistically significant increase in mortality (adjusted odds ratio [AOR] 2.95; 95% CI 1.18 to 7.41; p = 0.02), composite morbidity (AOR 2.19; 95% CI 1.56 to 3.07; p < 0.0001), bleeding (AOR 1.86; 95% CI 1.11 to 3.12; p = 0.02), return to the operation room (AOR 1.90; 95% CI 1.16 to 3.12; p = 0.01), and readmission related to the first operation (AOR 1.55; 95% CI 1.00 to 2.39; p = 0.05). On the other hand, retained common bile duct stones were 2.8 times more likely to occur in the laparoscopic group. The mean operative time was longer by 73 minutes for patients who underwent open CBDE.Conclusions: Patients undergoing open CBDE suffer from a statistically significantly higher rate of mortality and overall complications compared with patients undergoing the laparoscopic approach. Laparoscopic CBDE should be considered as the preferred procedure whenever possible. [ABSTRACT FROM AUTHOR]

A series of salicylketimines (2-[(2,6-diisopropylphenylimino)ethyl]phenol, 2-[(2,6-diisopropylphenylimino)ethyl]naphthol and 2-[(2,6-diisopropylphenylimino)(phenyl)-methyl]phenol), and their nickel complexes of general forms [(salicylketiminato)-Ni(PPh3)(Ph)] and [(salicylketiminato)2Ni] were synthesized and characterized. The formation of monophenyl-nickel(II) complexes versus the corresponding bis(sal)Ni(II) complexes depends on the fine tuning of the reaction work up and is affected by the substituent at the ketimine. Salicylketimines were thus found to form more readily the bis(sal)Ni(II) complexes than salicylaldimines. The molecular structures of the complexes were determined by X-ray crystallography and in all of them Ni has a nearly ideal square-planar coordination sphere. [Copyright &y& Elsevier]

The merit of this manuscript is to examine numerically a heated vertical plate with uniform temperature subjected to a steady, viscous, incompressible micro-polar fluid flow that is situated inside a saturated porous medium with permeability and porosity. Similarity variables have been applied to convert coupled of constrained partial differential equations that describe physical problem into coupled of constrained nonlinear ordinary differential equations, which in turn allows for the reliable numerical solution of the problems. Finite difference and shooting methods coupled with Runge-Kutta scheme have been implemented by Matlab function bvp4c to solve equations numerically. The graphical findings showed the impact of emerging dimensionless physical parameters for micro- polar liquid on non-dimensional velocity, temperature, and micro-rotation distributions. The latest findings exhibit a high degree of agreement with the findings from earlier research. Elevating parameter values drive to an increase in the velocity profile values, but a decrease in the temperature distribution values. The benchmarks parameters of this research are modified vortex viscosity and micro-inertia density. The high porosity in the range of 0.7–0.9 is considered the noteworthy limitation of the current study. Furthermore, increasing the material's physical characteristics cause the micro-rotation vorticity profile's curvature to flip. [ABSTRACT FROM AUTHOR]