Pancreatic cancer in Saudi Arabia (2005-2020): increasing trend.

Pancreatic cancer, a highly fatal malignancy, has shown a global rise in the incidence and mortality rates. However, these rates vary significantly across different regions worldwide. This study aims to assess the incidence and mortality of pancreatic cancer in Saudi Arabia. We collected the data from 16 annual cancer incidence reports in Saudi Arabia for the study period (2005-2020) and from the WHO's IARC Global Cancer Observatory website. Although the burden of pancreatic cancer in Saudi Arabia is relatively lower compared to global rates, the disease incidence has shown a steady increase over the study period, in addition to regional variations within the country. The disease predominantly affects the elderly population, aged 50 years and above in both genders, with males exhibiting higher rates than females. Further studies are required to identify the potential risk factors for pancreatic cancer in the Saudi population.

Nutritional Value and in vitro Antigiardial Activity of Anise (Pimpinella anisum L.) Seeds.

The present study focused on evaluating the proximate analysis, mineral composition, and in vitro anti-giardial activity of Pimpinella anisum seed extracts, which are aromatic plants with a long history of usage in folk and conventional medicine, as well as pharmaceutical manufacturing. Standard methods were used to determine the proximate analysis of the powdered plant sample, including dry matter, ash, fat, protein, fiber, and carbohydrates. The mineral contents of Pimpinella anisum seed were analyzed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS), revealing that the plant has a high fiber content (42.62%) followed by carbohydrates (38.79%). The seeds were also found to be a rich source of minerals, with notable amounts of Rubidium, Magnesium, and Calcium. The extracts showed a high mortality percentage compared to Metronidazole, with the chloroform extract exhibiting higher anti-giardial activity (78.71%) than the ethanolic extract (75.29%) at a concentration of 500 ppm. These findings support the traditional use of Anise in treating gastrointestinal issues and as a natural supplement. Further studies are needed to isolate the active ingredients and understand their mechanism of action.

Left atrial appendage closure in end-stage renal disease and hemodialysis: Data from a German multicenter registry.

BACKGROUND: Left atrial appendage closure (LAAC) has emerged as an alternative to oral anticoagulation (OAC) for stroke prevention in patients with atrial fibrillation (AF). OAC treatment has been proven feasible in mild-to-moderate chronic kidney disease (CKD). In contrast, the optimal antithrombotic management of AF patients with end-stage renal disease (ESRD) is unknown and LAAC has not been proven in these patients in prospective randomized clinical trials. OBJECTIVES: The objective of this study is to evaluate safety and efficacy of LAAC in patients with ESRD. METHODS: Patients undergoing LAAC were collected in a German multicenter real-world observational registry. A composite endpoint consisting of the occurrence of ischemic stroke/transient ischemic attack, systemic embolism, and/or major clinical bleeding was assessed. Patients with ESRD were compared with propensity score-matched patients without severe CKD. ESRD was defined as a glomerular filtration rate < 15 ml/min/1.73 m2 or chronic hemodialysis treatment. RESULTS: A total of 604 patients were analyzed, including 57 with ESRD and 57 propensity-matched patients. Overall, 596 endocardial and 8 epicardial LAAC procedures were performed. Frequency of major complications was 7.0% (42/604 patients) in the overall cohort, 8.8% (5/57 patients) in patients with ESRD, and 10.5% (6/57 patients) in matched controls (p = 0.75). The estimated event-free survival of the combined endpoint after 500 days was 90.7 ± 4.5% in patients with ESRD and 90.2 ± 5.5% in matched controls (p = 0.33). CONCLUSIONS: LAAC had comparable procedural safety and clinical efficacy in patients with ESRD and patients without severe CKD.

Is the outcome of elective vs non-elective patients undergoing transcatheter aortic valve implantation different? Results of a single-centre, observational assessment of outcomes at a large university clinic.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) can either be conducted as an elective (scheduled in advance) or a non-elective procedure performed during an unplanned hospital admission. The objective of this study was to compare the outcomes of elective and non-elective TAVI patients. METHODS: This single-centre study included 512 patients undergoing transfemoral TAVI between October 2018 and December 2020; 378 (73.8%) were admitted for elective TAVI, 134 (26.2%) underwent a non-elective procedure. Our TAVI programme entails an optimized fast-track concept aimed at minimizing the total length of stay to ≤ 5 days for elective patients which in the German healthcare system is currently defined as the minimal time period to safely perform TAVI. Clinical characteristics and survival rates at 30 days and 1 year were analysed. RESULTS: Patients who underwent non-elective TAVI had a significantly higher comorbidity burden. Median duration from admission to discharge was 6 days (elective group 6 days versus non-elective group 15 days; p < 0.001), including a median postprocedural stay of 5 days (elective 4 days versus non-elective 7 days; p < 0.001). All-cause mortality at 30 days was 1.1% for the elective group and 3.7% for non-elective patients (p = 0.030). At 1 year, all-cause mortality among elective TAVI patients was disproportionately lower than in non-elective patients (5.0% versus 18.7%, p < 0.001). In the elective group, 54.5% of patients could not be discharged early due to comorbidities or procedural complications. Factors associated with a failure of achieving a total length of stay of ≤ 5 days comprised frailty syndrome, renal impairment as well as new permanent pacemaker implantation, new bundle branch block or atrial fibrillation, life-threatening bleeding, and the use of self-expanding valves. After multivariate adjustment, new permanent pacemaker implantation (odds ratio 6.44; 95% CI 2.59-16.00), life-threatening bleeding (odds ratio 4.19; 95% confidence interval 1.82-9.66) and frailty syndrome (odds ratio 5.15; 95% confidence interval 2.40-11.09; all p < 0.001, respectively) were confirmed as significant factors. CONCLUSIONS: While non-elective patients had acceptable periprocedural outcomes, mortality rates at 1 year were significantly higher compared to elective patients. Approximately only half of elective patients could be discharged early. Improvements in periprocedural care, follow-up strategies and optimized treatment of both elective and non-elective TAVI patients are needed.

Neighborhood Walkability Is Associated with Physical Activity and Prediabetes in a Behavioral Weight Loss Study: a Secondary Analysis.

BACKGROUND: Socio-environmental factors may affect uptake and utility of behavioral interventions targeting weight loss and cardiometabolic health. To evaluate the relation of neighborhood walkability to physical activity (PA) and glucose control in a sample of adults with overweight/obesity participating in a weight loss study. METHODS: Secondary analysis of a 12-month behavioral weight loss intervention (2011-2015) using one-group pretest-posttest design. Neighborhood walkability was assessed via residential Walk Score (0-100) at study entry. Fasting plasma glucose (FPG) via phlebotomy and PA via waist-worn ActiGraph GT3X were assessed at baseline and end of study. Study variables included neighborhood walkability (car-dependent: Walk Score < 50 vs. walkable: Walk Score ≥ 50), prediabetes (FPG 100-125 mg/dL), and recommended PA (moderate to vigorous PA [MVPA] > 22 min/day). Generalized linear model with logit link results were reported as adjusted odds ratios (AOR) with 95% confidence intervals (CI). RESULTS: The sample (N = 114) was mostly female (88.6%), white (83.3%), college educated (73.7%), and on average 51.4 ± 1.0 years of age. At baseline, persons residing in car-dependent neighborhoods tended to have higher income than those in walkable neighborhoods. Neighborhood walkability interacted with household income at study entry to predict participants' ability to meet the MVPA goal at 12 months (AOR = 13.52, 95% CI: 1.86-119.20). Those from walkable neighborhoods had 67% lower odds of having prediabetes compared to those from car-dependent neighborhoods (AOR = 0.33, 95% CI: 0.10-0.87) at 12 months. CONCLUSION: Our findings corroborate previous research characterizing the relationship between neighborhood walkability, PA, and prediabetes status. Key drivers of this impact warrant further investigation in a study with a larger, more diverse sample.

Variable-Length Multiobjective Social Class Optimization for Trust-Aware Data Gathering in Wireless Sensor Networks.

Data gathering in wireless sensor networks (WSNs) is vital for deploying and enabling WSNs with the Internet of Things (IoTs). In various applications, the network is deployed in a large-scale area, which affects the efficiency of the data collection, and the network is subject to multiple attacks that impact the reliability of the collected data. Hence, data collection should consider trust in sources and routing nodes. This makes trust an additional optimization objective of the data gathering in addition to energy consumption, traveling time, and cost. Joint optimization of the goals requires conducting multiobjective optimization. This article proposes a modified social class multiobjective particle swarm optimization (SC-MOPSO) method. The modified SC-MOPSO method is featured by application-dependent operators named interclass operators. In addition, it includes solution generation, adding and deleting rendezvous points, and moving to the upper and lower class. Considering that SC-MOPSO provides a set of nondominated solutions as a Pareto front, we employed one of the multicriteria decision-making (MCDM) methods, i.e., simple additive sum (SAW), for selecting one of the solutions from the Pareto front. The results show that both SC-MOPSO and SAW are superior in terms of domination. The set coverage of SC-MOPSO is 0.06 dominant over NSGA-II compared with only a mastery of 0.04 of NSGA-II over SC-MOPSO. At the same time, it showed competitive performance with NSGA-III.

Preparation and Characterization of Poly(vinyl acetate-co-2-hydroxyethyl methacrylate) and In Vitro Application as Contact Lens for Acyclovir Delivery.

A series of poly(vinyl acetate-co-2-hydroxyethylmethacrylate)/acyclovir drug carrier systems (HEMAVAC) containing different acyclovir contents was prepared through bulk free radical polymerization of 2-hydroxyethyl methacrylate with vinyl acetate (VAc) in presence of acyclovir (ACVR) as the drug using a LED lamp in presence of camphorquinone as the photoinitiator. The structure of the drug carrier system was confirmed by FTIR and 1HNMR analysis, and the uniform dispersion of the drug particles in the carrier was proved by DSC and XRD analysis. The study of the physico-chemical properties of the prepared materials, such as the transparency, swelling capacity, wettability and optical refraction, was carried out by UV-visible analysis, a swelling test and measurement of the contact angle and the refractive index, respectively. The elastic modulus and the yield strength of the wet prepared materials were examined by dynamic mechanical analysis. The cytotoxicity of the prepared materials and cell adhesion on these systems were studied by LDH assay and the MTT test, respectively. The results obtained were comparable to those of standard lenses with a transparency of 76.90-89.51%, a swelling capacity of 42.23-81.80% by weight, a wettability of 75.95-89.04°, a refractive index of 1.4301-1.4526 and a modulus of elasticity of 0.67-1.50 MPa, depending on the ACVR content. It was also shown that these materials exhibit no significant cytotoxicity; on the other hand, they show significant cell adhesion. The in vitro dynamic release of ACVR in water revealed that the HEMAVAC drug carrier can consistently deliver uniformly adequate amounts of ACVR (5.04-36 wt%) over a long period (7 days) in two steps. It was also found that the solubility of ACVR obtained from the release process was improved by 1.4 times that obtained by direct solubility of the drug in powder form at the same temperature.

Producing and Testing Prototype Tissue-Engineered 3D Tri-Leaflet Valved Stents on Biodegradable Poly-ε-Caprolactone Scaffolds.

Transcatheter pulmonary valve replacement is a minimally-invasive alternative treatment for right ventricular outflow tract dysfunction and has been rapidly evolving over the past years. Heart valve prostheses currently available still have major limitations. Therefore, one of the significant challenges for the future is the roll out of transcatheter tissue engineered pulmonary valve replacement to more patients. In the present study, biodegradable poly-ε-caprolactone (PCL) nanofiber scaffolds in the form of a 3D leaflet matrix were successfully seeded with human endothelial colony-forming cells (ECFCs), human induced pluripotent stem cell-derived MSCs (hMSCs), and porcine MSCs (pMSCs) for three weeks for the generation of 3D tissue-engineered tri-leaflet valved stent grafts. The cell adhesion, proliferation, and distribution of these 3D heart leaflets was analyzed using fluorescence microscopy and scanning electron microscopy (SEM). All cell lineages were able to increase the overgrown leaflet area within the three-week timeframe. While hMSCs showed a consistent growth rate over the course of three weeks, ECFSs showed almost no increase between days 7 and 14 until a growth spurt appeared between days 14 and 21. More than 90% of heart valve leaflets were covered with cells after the full three-week culturing cycle in nearly all leaflet areas, regardless of which cell type was used. This study shows that seeded biodegradable PCL nanofiber scaffolds incorporated in nitinol or biodegradable stents will offer a new therapeutic option in the future.

Characteristics and outcomes of adult patients with asthma presenting with COVID-19: A comparative cohort study.

BACKGROUND: Bronchial asthma affects about 20% of Qatar's population. The impact of asthma on COVID-19 outcomes is controversial. The aim of this study was to explore the impact of asthma on COVID-19 outcomes and the predictors of COVID-19-related morbidity and mortality in a cohort of asthma patients infected by COVID-19. METHODS: This is a retrospective cohort study of adult patients with asthma infected with COVID-19, who were recruited from Hamad Medical Corporation (HMC), the main healthcare system in Qatar. Patients were matched to a control group of non-asthmatic COVID-19 patients (1:2) based on sex, age, and other comorbidities. RESULTS: Between March and August 2020, 616 patients with asthma met the inclusion criteria. The need for hospitalization among patients with asthma was independently associated with older age (adjusted odds ratio [aOR] for 10 years, 1.32; 95% confidence interval [CI], 1.13-1.54; p = 0.001) and hypertension (aOR, 2.4; 95% CI, 1.43-3.93; p = 0.001) but not with the use of inhaled corticosteroids (ICS), long-acting beta2 agonists, montelukast, or tiotropium. Patients with asthma required less hospitalization for COVID-19 than non-asthmatic patients (28.2% vs. 37.3%, respectively; aOR, 0.59; 95% CI, 0.77-0.90; p < 0.001). However, admission to the intensive care unit (ICU) was comparable between both groups (3.3% vs. 2.2%; aOR, 1.64; 95% CI, 0.78-3.43; p = 0.193). No difference in mortality rate was observed between the two groups. CONCLUSIONS: In Qatar, adult patients with asthma do not appear to be at higher risk of COVID-19-related hospitalization or ICU admission compared to the general adult COVID-19-infected population. Older age and hypertension were the only significant predictors of COVID-19-related hospitalization among patients with asthma. Further larger studies are required to confirm such an association.

Associations Between Physical Activity and Changes in Weight Across 7 Years After Roux-en-Y Gastric Bypass Surgery: A Multicenter Prospective Cohort Study.

OBJECTIVE: To examine associations of objectively-measured physical activity (PA) with changes in weight after roux-en-Y gastric bypass (RYGB) over 7 years. BACKGROUND: The contribution of free-living PA to surgery-induced weight loss and subsequent weight regain is not well understood. METHODS: Participants of a multi-center prospective cohort study of bariatric surgery were followed annually ≥7 years. Of 807 participants who underwent RYGB and were given an activity monitor, 649 (80%) had sufficient data for this report (78% female; median age 47 years; median body mass index 46 kg/m2). Mean daily steps, hours/day in SB and minutes/week in moderate-to-vigorous physical activity (MVPA) were determined at each assessment. Mixed models tested associations between PA measures and weight outcomes, controlling for sociodemographics, health status, and eating behaviors. RESULTS: Across follow-up, mean pre to postsurgery changes in PA were small, and mean postsurgery PA level was below PA recommendations for health (eg, 101 MVPA min/week 7 years postsurgery versus the ≥150 MVPA min/week recommendation). There was a dose-response association between more steps, less SB and more MVPA with greater weight loss. Steps and SB, but not MVPA, were also associated with weight regain. For example, participants in the highest versus lowest steps quartile lost 2.9% (95% confidence interval, 1.8-4.1) more of their presurgery weight and regained 5.4% (95% confidence interval, 2.4-8.3) less of their maximum weight lost across follow-up. CONCLUSIONS: Despite only small increases in objectively-measured PA level after RYGB, PA level was independently associated with weight outcomes of bariatric surgery throughout 7 years of follow-up. REPRINTS: Reprints will not be available from the authors.

Efficacy of core stability training on upper extremity performance in collegiate athletes.

OBJECTIVE: To determine the efficacy of a five-week core stability training program for collegiate athletes on upper extremity performance measures. METHODS: Seventy healthy collegiate athletes (age 21.6±1.7years; height 175±4.63 cm; body mass 65.31±5.63 kg) were randomly allocated to experimental (n=35) and control group (n=35). The experimental group has undergone a five-week core stabilisation protocol (three days /week) and regular training, whereas the control group maintained their regular training. The upper quarter Y balance test (UQ-YBT) and Functional throwing performance index (FTPI) were assessed pre and post-training. RESULTS: The results of mixed ANOVA show that there was a significant interaction between time and group variables on YBT (p<0.001, ηp2 =0.759) and FTPI (p<0.001, ηp2 =0.411) after five weeks of core stability training. Statistically, significant improvement was shown in YBT (mean change=15.2, p<0.001) and FTPI (mean change=14.4, p<0.001) in the experimental group; however, there was no significant change observed in both outcomes in the control groups. CONCLUSION: After five weeks of core stabilisation training program, the measures of UQ-YBT and FTPI were improved, thus advocating the use of a core stabilisation training program among collegiate athletes to enhance their upper extremity performance.

An Eco-Friendly Quaternary Ammonium Salt as a Corrosion Inhibitor for Carbon Steel in 5 M HCl Solution: Theoretical and Experimental Investigation.

The corrosion of industrial material is a costly problem associated with global economic losses reaching trillions of US dollars in the repair of failures. Injecting corrosion inhibitors is the most practically promising method for decelerating corrosion reactions and protecting surfaces. Recent investigations have focused on surfactants as corrosion inhibitors due to their amphiphilic nature, low cost, and simple chemical preparation procedures. This study aims to investigate the performance of an environment-friendly Quaternium-22 (Q-22) surfactant which is widely used in cosmetics for C-steel corrosion inhibition in a 5 M HCl medium. Weight loss experiments were performed at different concentrations and immersion times, presenting a maximum efficiency at 2.22 mmol·L-1. The influence of Q-22 on the corrosion behavior of C-steel was elucidated using non-destructive electrochemical measurements. The overall results revealed that adding varied concentrations of Q-22 significantly decreases the corrosion rate of C-steel. The results revealed the physisorption nature of Q-22 onto the C-steel surface, with adsorption following the Freundlich isotherm (∆Hads= -16.40 kJ·mol-1). The relative inhibition performance of Q-22 was also evaluated by SEM and AFM analyses. Lastly, quantum chemical calculations based on density functional theory (DFT) demonstrated that Q-22 has promising molecular features concerning the anticorrosive mechanism.

Excessive daytime sleepiness and associations with sleep-related motor vehicle accidents: results from a nationwide survey.

OBJECTIVE/BACKGROUND: Insufficient sleep can have fatal consequences, and up to 30% of motor vehicle accidents (MVAs) are related to driving when drowsy. The objective of this study was to investigate how sleep quality and excessive daytime sleepiness (EDS) affect falling asleep while driving and sleep-related MVAs/near-misses. PARTICIPANTS/METHODS: A population-wide sample of Saudi adults was surveyed. The questionnaire gathered data on sleep quality, EDS (Epworth Sleepiness Scale), and episodes of falling asleep while driving and sleep-related MVAs/near-misses in the previous year. Univariable and multivariable analyses were used to assess associations. RESULTS: A total of 19% (902/3802) and 10% (474/4229) of respondents had fallen asleep while driving or had a sleep-related MVA/near-miss in the preceding year, respectively. Being male, married, having a shorter sleep duration, being an office worker, having poor subjective sleep quality, and having moderate or severe EDS were associated with an increased risk of having fallen asleep while driving in the previous year. Younger age, male gender, having worse subjective sleep quality [OR 2.11 (95% CI 1.36-3.29); p < 0.0001 for "very bad" sleep quality], and having moderate or severe EDS [ESS ≥ 13; OR 1.90 (95% CI 1.38-2.60); p < 0.0001 and OR 2.39 (95% CI 1.56-3.67); p < 0.0001, respectively] were associated with having had/nearly had an accident due to being tired or falling asleep while driving in the previous year. CONCLUSIONS: Sleepy driving and sleep-related accidents/near-misses are common in Saudi Arabia, and sleep quality and EDS contribute to the burden of MVAs. Further efforts are required to quantify the contribution of sleepiness to MVAs to develop and prioritize interventions to prevent MVA-related injuries and death.

The role of Sociodemographic factors on goal achievement in a community-based diabetes prevention program behavioral lifestyle intervention.

BACKGROUND: The Diabetes Prevention Program (DPP) behavioral lifestyle intervention was effective among a diverse sample of adults with prediabetes. Demonstrated effectiveness in translated versions of the DPP lifestyle intervention (such as Group Lifestyle Balance, DPP-GLB) led to widescale usage with national program oversight and reimbursement. However, little is known about the success of these DPP-translation programs across subgroups of sociodemographic factors. This current effort investigated potential disparities in DPP-translation program primary goal achievement (physical activity and weight) by key sociodemographic factors. METHODS: Data were combined from two 12-month community-based DPP-GLB trials among overweight/obese individuals with prediabetes and/or metabolic syndrome. We evaluated change in weight (kilograms and percent) and activity (MET-hrs/week) and goal achievement (yes/no; ≥5% weight loss and 150 min per week activity) after 6 and 12 months of intervention within and across subgroups of race/ethnicity (non-Hispanic white, non-Hispanic black), employment status, education, income, and gender. RESULTS: Among 240 participants (85%) with complete data, most sociodemographic subgroups demonstrated significant weight loss. However, non-Hispanic white lost more weight at both 6 and 12 months compared to non-Hispanic black participants [median weight loss (IQR), 6 months: 5.7% (2.7-9.0) vs. 1.5% (1.2-7.5) p = .01 and 12 months: 4.8% (1.1-9.6) vs. 1.1% (- 2.0-3.7) p = .01, respectively]. In addition, a larger percentage of non-Hispanic white demonstrated a 5% weight loss at 6 and 12 months. Employment was significantly related to 12-month weight loss, with retired participants being the most successful. Men, participants with graduate degrees, and those with higher income were most likely to meet the activity goal at baseline and 12 months. Differences in physical activity goal achievement across gender, education, and income groups were significant at baseline, attenuated after 6 months, then re-emerged at 12 months. CONCLUSIONS: The DPP-GLB was effective in promoting weight loss and helped to alleviate disparities in physical activity levels after 6 months. Despite overall program success, differences in weight loss achievement by race/ethnicity were found and disparities in activity re-emerged after 12 months of intervention. These results support the need for intervention modification providing more tailored approaches to marginalized groups to maximize the achievement and maintenance of DPP-GLB behavioral goals. TRIAL REGISTRATION: NCT01050205 , NCT02467881 .

Laminar flowmeter for mechanical ventilator: Manufacturing challenge of Covid-19 pandemic.

The rapid and sudden attack of the covid-19 pandemic has emerged the urgent need for pulmonary resuscitation devices (ventilators). The airflow sensor is a main element in the ventilator. Sensing very low airflow rates is an essential requirement to meet the least significant bit of the analogue to digital converter included in the ventilator. This short communication describes the fabrication and test of five flow sensors using basic and the 3D printing techniques to overcome the severe challenge arising from the pandemic under strict quarantine. The principle of these five flow sensors is based on Fleisch pneumotachograph technology, which creates a pseudo-laminar flow within a bundle of capillary tubes. Amongst the five tested sensors, those fabricated by 3D printing technique were the most accurate and reliable. Results show that the 3D printed sensor of 33 trapezoidal capillary tubes and displaced pressure taps meet the requirement of sensing flowrates with less resistance to patient at exhalation and more linearity figure. The experimental data were correlated using a sophisticated MMF correlation with an R-squared factor of 0.9999 and a percentage error of 1.68%.

Nanosheet Synthesis of Mixed Co3O4/CuO via Combustion Method for Methanol Oxidation and Carbon Dioxide Reduction.

This paper represents a study of mixed Co3O4/CuO nanosheet (NS) synthesis via solution combustion synthesis for oxidation of methanol and carbon dioxide (CO2) conversion. The mixed oxide NS of Co3O4/CuO is a hybrid structure of Co3O4 and CuO NSs. We applied this mixed oxide NS of Co3O4/CuO for methanol oxidation and carbon dioxide (CO2) conversion, and the results revealed that the activity of the mixed oxide NS surpassed the activity of the corresponding individual Co3O4 and CuO metal oxide NSs, both in methanol oxidation and in CO2 conversion. The mass activity of the mixed Co3O4/CuO NS produced at 0.627 V versus Ag/AgCl during methanol oxidation (0.5 M) was 12 mA g-1, which is 2.4 times better than that of Co3O4, whose mass activity is 5 mA g-1, and 4 times better than that of the CuO NS, whose mass activity is 3 mA g-1. The methanol oxidation peak at 0.62 V versus Ag/AgCl was also more intense than individual oxides. The trend in performance of methanol oxidation follows the order: Co3O4/CuO > Co3O4 > CuO. In the case of CO2 reduction, we experienced that our product was formate, and this was proved by formate oxidation (formate is formed as a product during the reduction of CO2) on the surface of the Pt ring of a rotating ring-disc electrode. Similar to methanol oxidation, Co3O4/CuO also showed superior activity in carbon dioxide reduction. It was experienced that at -1.5 V, the current density rises to -24 mA/cm2 for the Co3O4/CuO NS, that is, 0.6 times that of the CuO NS, which is -15 mA/cm2, and 3 times more than that of the Co3O4 NS, which is 8 mA/cm2. The trend in performance of CO2 reduction follows the order: Co3O4/CuO > CuO > Co3O4.

Development of a computational tool for estimating computed tomography dose parameters.

BACKGROUND: Computed Tomographic (CT) imaging procedures have been reported as the main source of radiation in diagnostic procedures compared to other modalities. To provide the optimal quality of CT images at the minimum radiation risk to the patient, periodic inspections and calibration tests for CT equipment are required. These tests involve a series of measurements that are time consuming and may require specific skills and highly-trained personnel. OBJECTIVE: This study aims to develop a new computational tool to estimate the dose of CT radiation outputs and assist in the calibration of CT scanners. It may also provide an educational resource by which radiological practitioners can learn the influence of technique factors on both patient radiation dose and the produced image quality. METHODS: The computational tool was developed using MATLAB in order to estimate the CT radiation dose parameters for different technique factors. The CT radiation dose parameters were estimated from the calibrated energy spectrum of the x-ray tube for a CT scanner. RESULTS: The estimated dose parameters and the measured values utilising an Adult CT Head Dose Phantom showed linear correlations for different tube voltages (80 kVp, 100 kVp, 120 kVp, and 140 kVp), with R2 nearly equal to 1 (0.99). The maximum differences between the estimated and measured CTDIvol were under 5 %. For 80 kVp and low tube currents (50 mA, 100 mA), the maximum differences were under 10%. CONCLUSIONS: The prototyped computational model provides a tool for the simulation of a machine-specific spectrum and CT dose parameters using a single dose measurement.

Impact of transcatheter mitral valve repair on ventricular arrhythmias.

AIMS: Patients with heart failure and severe mitral regurgitation (MR) have a poor prognosis and carry an increased risk for ventricular arrhythmias. The present study evaluates the impact of transcatheter mitral valve repair using the MitraClip on the potential reduction of ventricular arrhythmias. METHODS AND RESULTS: Patients undergoing MitraClip implantation were prospectively enrolled into the present study and received 24 h Holter ECG assessment prior to and 6 months after the procedure. In addition, left ventricular dimensions and function were assessed at baseline and follow-up. A total of 50 patients with mainly functional MR (82%) were included. Non-sustained or sustained ventricular tachycardia (nsVT and/or sVT) occurred in 32% of patients and was reduced to 14% at follow-up (P = 0.01). Also, premature ventricular complex (PVC) burden ≥5% decreased from 16% to 4% (P = 0.04). Patients with persistent (n = 6) or new (n = 1) nsVT and/or sVT at follow-up showed a significant decrease in left ventricular ejection fraction from 38% (interquartile range 26-45%) to 33% (interquartile range 22-44%; P = 0.03). CONCLUSIONS: In this prospective study, transcatheter mitral valve repair using MitraClip was associated with a reduced prevalence of ventricular arrhythmias. The subset of patients with persistent or new ventricular arrhythmias after MitraClip implantation showed progression of left ventricular dysfunction.

Kleine-Levin syndrome: clues to aetiology.

Kleine-Levin syndrome (KLS) is the commonest recurrent sleep disorder, with a prevalence of 1-2 per million population. Clear diagnostic criteria are now defined, but effective treatment remains elusive. The significant body of published literature allows consideration of possible aetiological mechanisms, an understanding of which could guide the development of therapeutic strategies. Functional imaging studies have been inconclusive; although diencephalic abnormalities are a common finding, no consistent pattern has emerged, and these studies have not revealed the mechanism(s) underlying the development of the abnormalities detected. An autoimmune aetiology is consistent with the available data. In this review, we argue that, in order to further our understanding of KLS, there needs to be a co-ordinated international effort to standardise approaches to functional imaging studies, genetic analyses that specifically address the possibility of an autoimmune aetiology, and clinical trials of immunosuppressive therapies.