Screening, awareness and challenges for colorectal cancer treatment in Saudi Arabia: an update.

Colorectal cancer (CRC) is the second most common cancer in the world. In Saudi Arabia, CRC is the most common cancer in males and the third most common in females, and its incidence rate is rising as the country continues to develop. However, the country does not have a national CRC screening program for CRC. This review aims to review recent studies that have attempted to address and rectify this issue and discern the most notable and prevalent barriers. Despite these efforts, guidelines are still lacking. Two prospective studies have been conducted in recent years, one of which was a national pilot screening program conducted by the Ministry of Health (MOH). While both had a similar number of participants, the colonoscopy rate for patients with a positive fecal immunochemical test (FIT) in the MOH program was only 20% compared to 75.8% in the Al-Kharj program. Awareness of the Saudi population regarding CRC and its screening appears to be insufficient. The most common barriers to patients' willingness to undergo screening were embarrassment, fear, and pain. Barriers to physicians are mostly related to factors outside their hands, such as lack of equipment and time. We conclude that efforts should be made to establish a national screening program and improve awareness of the population and physicians.

The Prevalence of Shoulder Pain and Awareness of Frozen Shoulder Among the General Population in Taif City, Saudi Arabia.

Background The global prevalence of shoulder pain varies widely across countries. Additionally, shoulder pain and frozen shoulder can significantly affect patients' quality of life due to high levels of pain and disability. Objective This study aimed to investigate the prevalence of shoulder pain and its risk factors. It also aims to assess the level of knowledge regarding frozen shoulders and its related factors in Taif City, Saudi Arabia. Methods A cross-sectional observational study was conducted in Taif City in December 2023 using a validated questionnaire comprised of socio-demographic characteristics, the prevalence of shoulder pain, and the awareness of frozen shoulders. Results A total of 378 participants enrolled in the study, with 54.8% being male and 62.7% being graduates and having jobs equally distributed among office (24.9%) and in the field (24.9%). Most participants were smokers (75.9%) and did not engage in body-building activities (79.6%). Around 26.5% of them had diabetes. The prevalence of shoulder pain was 32.8%. Aging from 35 to 44 years (p<0.001), having a higher salary from 6000 to 10000 SAR (p<0.001), retirement (p<0.001), engaging in body-building activities (p=0.035), having diabetes (p<0.001), and having other comorbidities (p<0.001) are significantly impacted having shoulder pain. Increased knowledge about the frozen shoulder is correlated with aging from 25-34 (p=0.026), smoking (p=0.002), engaging in bodybuilding (p<0.001), having diabetes (p=0.010), and having other medical conditions (p=0.010). Conclusion The study has shown that shoulder pain is prevalent among Taif City's population. Nevertheless, a low level of knowledge was observed. Therefore, enhancing the national educational programs is needed to increase public awareness of frozen shoulders.

Prevalence of nasal obstruction and its impact on quality of life in Saudi Arabia.

Purpose/Background: Nasal obstruction is a significant issue influencing the patient's quality of life. Chronic nasal obstruction is frequently associated with other symptoms such as headache, sleep disturbance, and daytime sleepiness. This study aims to investigate the prevalence of nasal obstruction in Saudi Arabia and examine its effect on patients' quality of life. Methods: This is a cross-sectional study conducted in Saudi Arabia. Data were collected using a self-administered combination of two previously validated questionnaires (the NOSE scale and the WHOQOL-BREF) translated into Arabic. The Mann-Whitney test was used to investigate the association between nasal obstruction prevalence and the participants' QOL. Results: The study included 1039 participants from different regions of Saudi Arabia. The prevalence of nasal obstruction was 60.3% among the participants. Several factors significantly affected the prevalence of nasal obstruction, including sex, suffering from a chronic disease, having a family member with nasal obstruction, and using medications (P < 0.001 for all factors). A better score was shown in the four domains of the WHOQOL-BREF questionnaire by the participants who had no nasal obstruction: the physical health domain, psychological health, social relationships, and environment (P < 0.001 for all factors). Conclusions: Quality of life is affected by nasal obstruction. The subjective assessment is essential in evaluating the severity of nasal obstruction disease. It is recommended that healthcare providers use subjective tools combined with objective tools to assess the degree of nasal obstruction severity.

The Knowledge, Attitudes, and Practices Regarding Diabetic Ketoacidosis Among Diabetic Patients in the Northern and Western Regions of Saudi Arabia.

Background and objective Diabetes mellitus (DM) is a chronic debilitating metabolic disease caused by insulin deficiency. Diabetic ketoacidosis (DKA) is a potentially fatal complication characterized by acute hyperglycemia and metabolic acidosis. In light of the high prevalence of DM in Saudi Arabia, we sought to investigate the knowledge, attitudes, and practices of the Saudi general population about DKA. Methods An online self-administered questionnaire was distributed through popular social media platforms among diabetics in the Saudi population. The survey questions involved demographic data; diabetes status including the time of diagnosis, current medications, and the latest HbA1c level; and an assessment of the knowledge about DKA through queries related to diagnostic criteria, definition, risk factors, symptoms, and preventive measures. Results Our study involved 400 participants, and 42.5% of them were able to correctly identify DKA as an emergency requiring immediate medical attention. Regarding the awareness of DKA's symptoms among the participants, 33.8% correctly identified excessive thirst as a key indicator, followed closely by frequent urination (31.8%), and the characteristic fruity breath odor (31.3%). As for the awareness of the participants of the causes of DKA, 33.8% correctly linked forgetting insulin injections to DKA development. Encouragingly, 39.8% of participants identified regular blood sugar monitoring as the most effective way to prevent DKA. Conclusions Most patients in our study demonstrated limited knowledge of DKA. However, a significant portion of them was able to identify it as an emergency. To prevent such events, raising awareness about DM and its complications may serve as the first step toward better outcomes in diabetic patients. We believe our findings can be used to devise quality-improving interventions in this field.

Enhancing the engineering characteristics of sustainable recycled aggregate concrete using fly ash, metakaolin and silica fume.

The present global environment is facing growing issues linked to production of concrete, mostly due to high consumption of concrete as the dominating construction material globally. In today's climate of environmental sustainability, recycled concrete production using RA (recycled aggregates) requires a more holistic approach. This study examined how recycled aggregate (RA), metakaolin, silica fume and fly ash affect mechanical characteristics (compressive strength, split tensile strength), and durability characteristics (acid resistance, absorption, sorptivity) of concrete. The objective of this investigation is to figure out how the potential of RA based concrete can be improved so that they can be used to their maximum extent. To achieve the desired outcome, the study involved testing three distinct groups of concrete samples, each containing different percentages (25%, 50%, and 75%) of recycled aggregate (RA) with a constant amount of silica fume, (25 kg/m3). The first group was used as the control mix, while the second group incorporated 10% fly ash, and the third group included 15% metakaolin. The findings of this research show that the RA concrete mechanical properties as well as durability can be significantly improved by incorporating 15% metakaolin and 10% fly ash. The investigation involves the examination of all ternary blends within two distinct acidic environments, specifically a 5% hydrochloric acid (HCl) solution and sulfuric acid (H2SO4). Both the ternary mixes (metakaolin and fly ash) with the combination of silica improve all characteristics. The quality assurance, cost analysis and the reduction of CO2 emissions are carried out, utilizing RA (recycled aggregates) as a substitute for NA (natural aggregate). In case of producing superior structural concrete, it is recommended based on results to limit the replacement percentage of recycled aggregate (RA) to a maximum of 50% in presence of 10% fly ash and 15% metakaolin, otherwise the RA replacement percentage should not be more than 25%.

Comparing the softening effect of three gutta-percha solvents on different types of gutta-percha with different application durations.

Introduction: During non-surgical endodontic retreatment, gutta-percha (GP) solvents are indispensable in difficult cases when used with mechanical removal, however studies comparing their efficacy against different types of GP are limited. The purpose of this study was to investigate the softening effect of three solvents on the conventional (CGP), cross-linked carrier-based (CLGP), and thermoplasticized (TGP) and compare the effect of time on the softening effect of the solvents. Methods: Tested GP were embedded in cuboidal blocks of stone with their upper surfaces exposed (1 mm diameter). Three commercial GP solvents based on D-Limonene (DL), Eucalyptol oil (EO), and orange oil (OO) were added to the exposed GP before an indenter (weight = 1Kg) was applied. Using a digital camera, the indentation depth was measured (mm) directly after applying the solvent and indenter (T = 0), and after 1, 2, and 3 min of application (T = 1,2,3). The means of indentation depth were calculated and compared using a two-way analysis of variance and Tukey's post-hoc test to assess the effect of the types of solvent, GP for each application duration, and Friedman's test to evaluate the effect of application duration on the softening effect of solvents. Results: The type of GP (F = 261.43, p < 0.001), type of solvent (F = 3.57, p = 0.015), and application duration (F = 53.088, p < 0.001) were all found to significantly affect GP softening. DL exhibited the highest and only significant effect on CGP after 1 min (p < 0.05), while OO had the only significant effect against CLGP when applied for at least 2 min (p < 0.05). Both OO and EO had significant softening effects on TGP instantly or after 1 min of application, respectively. Conclusions: The results of this study revealed that the softening effect of GP solvents varies depending on their type, their application duration, and the type of GP.

The clinical features and impact of SARS-CoV-2/COVID-19 infection in children with Cystic Fibrosis (CF): A Qatari experience.

BACKGROUND: SARS-CoV-2 in children with cystic fibrosis (CF) has been reported to cause mild illness without pre-existing severe lung disease. This review described the clinical presentation and course of COVID-19 infection in children with CF in Qatar. METHODS: The pediatric CF registry of 51 patients in Qatar was reviewed for COVID-19 cases from February 2020 to February 2022. Demographics, vaccination status, symptoms, and course were reviewed. Data were expressed as median, range, frequencies, and percentages. RESULTS: The study included eight patients with CF below 18 years of age infected with COVID-19. The incidence of COVID-19 in children with CF was 15.7%. The median age was 11 (2-18) years. Half of the cohort were males. Seven patients were pancreatic sufficient (I1234V mutation), and one was pancreatic insufficient (3129del4 mutation). The median baseline FEV1 was 91 (78-107%) predicted. None had received CFTR modulators or undergone a lung transplant. Three patients were vaccinated before their infections. Two of them were asymptomatic. Six patients (75%) had a cough and flu-like symptoms. Three patients had a fever. Two patients were hospitalized due to pulmonary exacerbation; both had mild CF-lung disease. None required respiratory support. CONCLUSION: We report a favorable outcome of COVID-19 infection in children with CF, similar to published international studies. Our findings are attributable to the community-dominant milder CFTR mutation, precautionary measures, and causative COVID-19 strain. More longitudinal data are needed to study these factors as potential protective mechanisms.

Pancreatitis Prevention in Tabuk City, Kingdom of Saudi Arabia: Evaluating Public Knowledge and Raising Awareness of Risk Factors and Symptoms.

INTRODUCTION: Pancreatitis is an inflammation of the pancreas. The pancreas is a flat, elongated gland situated in the upper abdomen, beyond the stomach. It produces digestive enzymes and hormones that regulate glucose absorption in the body. Pancreatitis can be acute, developing rapidly and lasting for several days, or chronic, persisting over an extended period and affecting specific individuals. While treatment can improve mild cases of pancreatitis, severe cases can be fatal. METHOD: This study utilizes a cross-sectional survey design with 549 participants, allowing data collection from a representative sample of Tabuk City's adult population. RESULTS: The participants' knowledge about the risk factors and symptoms of pancreatitis was inadequate. Among those who did not receive any information about pancreatitis and its risk factors, the count was 352 (64.1%). On the other hand, there was increased awareness of pancreatitis and its risk factors, which would lead to early detection and prevention. A total of 483 participants (88%) expressed adequate agreement, and 305 participants (55.6%) demonstrated an adequate response regarding seeking medical attention if they experienced any symptoms of pancreatitis. CONCLUSION: Our findings revealed a lack of knowledge about the risk factors and symptoms of pancreatitis. Furthermore, there was inadequate awareness regarding governmental initiatives or programs that support access to pancreatitis knowledge and awareness in Tabuk City.

Outcome and complications of outpatient parenteral therapy in pediatric emergency utilizing only peripheral vascular access: A retrospective descriptive study.

OBJECTIVES: To describe the cure and complication rates of outpatient parenteral therapy (OPT) utilizing only peripheral vascular access. METHODS: Using a retrospective descriptive study design, we reviewed the medical charts for children aged up to 15 years old who had been discharged from the emergency department into the care of the OPT unit from January 2018 to April 2019. The primary outcomes were cure and complication rates. RESULTS: Out of 814,150 visits, 2,788 (0.34%), accounting for 2,126 patients, were managed in the OPT unit. The majority had 2 days of symptoms, and 26.4% had comorbidities. Most patients started the treatment for suspected sepsis and suspected or confirmed urinary tract infections. The total days of therapy for all patients were 3,663. Cephalosporins were used for 75%, mostly ceftriaxone. Most patients completed the IV therapy within 2 days, 2.8% of cases required a change of antibiotics. Readmission avoidance and full recovery were achieved in 99.3%, and 0.7% needed readmission. All patients had peripheral vascular access. Complications occurred in 21%. Most were related to vascular access, but more than 80% were managed by one-time IV cannula re-insertion, and only 0.5% had treatment modification because of these complications. CONCLUSION: For carefully selected patients in the pediatric emergency, outpatient parenteral therapy seems effective, safe with manageable complications, and may result in less family disturbance than hospital admission.

External fixation versus intramedullary nailing for the management of open tibial fracture: meta-analysis of randomized controlled trials.

AIM: Tibial shaft fractures are the most common type of long-bone fractures. External fixation (EF) and intramedullary nailing (IMN) are widely used surgical techniques for the definitive fixation of open tibial shaft fractures. The aim of this systematic review and meta-analysis was to compare EF to IMN for the definitive fixation of open tibial fractures. METHODS: Medline, Embase, and CENTRAL databases were searched for eligible studies. We included randomized controlled trials (RCTs) that compared EF to IMN for skeletally mature adults with open tibial fracture (Gustilo I, II, and III). We evaluated the following outcomes: superficial infection, pin-track infection, deep infection, malunion, nonunion, delayed union, and implant/hardware failure. The risk ratio (RR) was used to represent the desired outcomes. The statistical analysis was performed using the random-effects model. RESULTS: A total of 12 RCTs that enrolled 1090 participants were deemed eligible for the analysis. EF showed a significantly higher rate of superficial infection, pin track infection, and malunion compared to IMN (RR = 2.30, 95% confidence interval (CI): 1.34 to 3.95; RR = 13.52, 95% CI: 6.16 to 29.66; RR = 2.29, 95% CI 1.41 to 3.73, respectively). No substantial difference was found between EF and IMN in terms of deep infection, nonunion, delayed union, or implant/hardware failure (RR = 1.15, 95% CI 0.67 to 1.98; RR = 0.92, 95% CI 0.77 to 1.10; RR = 1.50, 95% CI 0.98 to 3.33; RR = 0.96, 95% CI 0.36 to 2.60, respectively). DISCUSSION: The findings of our meta-analysis are consistent with the previous systematic reviews excepts for the implant/hardware failure which was found to be significant in favour of IMN by one of the previous reviews. CONCLUSION: This meta-analysis confirms that IMN is better than EF with respect to clinical outcomes and complication rate for the definitive fixation of open tibial fracture.

Doxycycline's Potential Role in Reducing Thrombosis and Mortality in Critically Ill Patients With COVID-19: A Multicenter Cohort Study.

Doxycycline has revealed potential effects in animal studies to prevent thrombosis and reduce mortality. However, less is known about its antithrombotic role in patients with COVID-19. Our study aimed to evaluate doxycycline's impact on clinical outcomes in critically ill patients with COVID-19. A multicenter retrospective cohort study was conducted between March 1, 2020, and July 31, 2021. Patients who received doxycycline in intensive care units (ICUs) were compared to patients who did not (control). The primary outcome was the composite thrombotic events. The secondary outcomes were 30-day and in-hospital mortality, length of stay, ventilator-free days, and complications during ICU stay. Propensity score (PS) matching was used based on the selected criteria. Logistic, negative binomial, and Cox proportional hazards regression analyses were used as appropriate. After PS (1:3) matching, 664 patients (doxycycline n = 166, control n = 498) were included. The number of thromboembolic events was lower in the doxycycline group (OR: 0.54; 95% CI: 0.26-1.08; P = .08); however, it failed to reach to a statistical significance. Moreover, D-dimer levels and 30-day mortality were lower in the doxycycline group (beta coefficient [95% CI]: -0.22 [-0.46, 0.03; P = .08]; HR: 0.73; 95% CI: 0.52-1.00; P = .05, respectively). In addition, patients who received doxycycline had significantly lower odds of bacterial/fungal pneumonia (OR: 0.65; 95% CI: 0.44-0.94; P = .02). The use of doxycycline as adjunctive therapy in critically ill patients with COVID-19 might may be a desirable therapeutic option for thrombosis reduction and survival benefits.

Outcomes of Cardiopulmonary Resuscitation and Predictors of Its Outcomes in the Emergency Department in King Saud Medical City, Saudi Arabia.

BACKGROUND: Cardiac arrest is a medical emergency marked by the cessation of cardiac mechanical activity and insufficient blood flow. CPR (cardiopulmonary resuscitation) is a life-saving method that involves restoring the essential functions of two vital organs: the heart and lungs. This study was conducted to identify the outcome of CPR in cardiac arrest patients presented to the emergency department (ED) and to identify predictors of CPR outcomes. METHODOLOGY: This was a retrospective, descriptive study. All in-hospital cardiac arrest patients who underwent CPR in the King Saud Medical City (KSMC) ED between January 2017 and January 2020 were analyzed, with a sample size of 351 patients. RESULTS: Overall return of spontaneous circulation (ROSC) and survival to discharge (STD) were achieved in 106 (30.2%) and 40 (11.39%) patients, respectively. When assessing the predictors of ROSC, the analyses showed that patient age, pre-arrest intubation, the method used to deliver oxygen, and CPR duration were all statistically significant predictors for ROSC. Similarly, when assessing predictors associated with STD, the analyses showed that patient age, pre-arrest intubation, the method used to deliver oxygen, and CPR duration were positively associated with STD. CONCLUSION: Comparing the study's findings to those of similar studies, it shows a CPR outcome rate within the range of similar studies. It also highlights that CPR outcomes are highly associated with CPR duration (a maximum of 30 minutes), younger age, and endotracheal intubation.

Foot kinematics in runners with plantar heel pain during running gait.

BACKGROUND: Plantar heel pain associated with plantar fascia pathology (PHP) is one of the most common running overuse injuries. Degeneration and changes in the mechanical properties of the plantar fascia associated with PHP can result in changes in foot kinematics during gait. RESEARCH QUESTION: How do running gait foot kinematics differ between female and male runners with and without PHP? METHODS: Retrospective study of 13 runners with PHP (7 female, 6 male) and a matched group of 13 uninjured runners (6 female, 7 male). A seven-segment foot model was used to quantify six functional articulations (rearfoot complex, lateral and medial midfoot, lateral and medial forefoot, and first metatarsophalangeal). Functional articulation ROM during early, mid, and propulsion running stance subphases was assessed. Two-way ANOVAs and Friedman's two-way ANOVA for ranks tests were conducted for normally distributed variables and non-normally distributed variables, respectively. RESULTS: During early stance, PHP runners demonstrated significantly increased lateral midfoot eversion ROM compared to uninjured runners. During the propulsion phase, male runners with PHP demonstrated increased medial midfoot eversion and dorsiflexion ROM and increased medial forefoot plantar flexion compared to uninjured male runners. Also during propulsion, females with PHP went through significantly less medial forefoot plantar flexion ROM compared to uninjured female runners. SIGNIFICANCE: Given the function of the plantar fascia to assist foot supination, the differences in runners with PHP, which were consistent with increased pronation or inadequate supination, may be the result of insufficient tension during the stance phase of running gait caused by degeneration of the plantar fascia. Further, the significant medial midfoot and medial forefoot group by sex interactions during propulsion suggest that PHP may affect male and female runners differently. Understanding the effect of PHP on foot function during running may aid in the development of future rehabilitation programs and/or treatment outcome assessments.

Predictors of Mortality in Adults With Sickle Cell Disease Admitted to the Intensive Care Unit in King Saud Medical City, Saudi Arabia.

Background Sickle cell disease (SCD) is the most common genetic blood disorder in Saudi Arabia. A limited number of studies have been conducted on SCD patients regarding their intensive care unit (ICU) admissions. We aimed to identify the cause of ICU admission in SCD patients and to identify predictors of mortality. Methodology We identified 64 patients with SCD, aged 14 years and older, who were admitted to the ICU of King Saud Medical City, Riyadh, Kingdom of Saudi Arabia, from January 1, 2017, to December 31, 2020. Results Acute chest syndrome was the most frequent primary diagnosis for ICU admission in 29 (45.3%) patients followed by vaso-occlusive crisis in 23 (35.9%) patients. Pregnancy in eight (12.5%) patients was the most prevalent co-existing condition. The median age was 29 years, with males comprising 45.3% and females comprising 54.7% of the study population. Arterial blood gas pH less than 7.2 on ICU admission (p= <0.001), hemodialysis support (p= 0.049), the use of vasopressors (p= 0.016), intubation (p= <0.001), and being intubated within the first 24 hours of ICU stay (p= 0.04) had a statistically significant association with mortality at ICU discharge out of all the variables tested. Mortality on ICU discharge was 7 (10.9%). Conclusion This was a retrospective study carried out in King Saud Medical City. Comparing the results of the study to those of similar ones conducted around the world revealed a low SCD ICU mortality rate. This low mortality may be a result of improved overall ICU care. We recommend a multi-center, prospective study in future.

Evaluating COVID-19 vaccination intentions and vaccine hesitancy among parents of children with autism spectrum disorder.

As the global vaccination mass campaign against COVID-19 extended to children aged 5 to 11 years, some parents remained hesitant about their children being administered the vaccine despite data supporting its safety. Parent vaccine hesitancy (PVH) may have predisposed certain groups of children, particularly those with autism spectrum disorder (ASD), to COVID-19 when other neurotypical children would have been vaccinated. We investigated the current PVH in 243 parents of children with ASD and 245 controls using the Parent Attitudes about Childhood Vaccines (PACV) scale. The study was conducted in Qatar from May to October 2022. Overall, 15.0% [95% CI 11.7%; 18.3%] of parents were vaccine-hesitant, with no difference (p = 0.054) between groups (ASD children [18.2%] vs. controls [11.7%]). The only sociodemographic factor associated with higher vaccine hesitancy was being a mother (as compared to being a father). The COVID-19 vaccine receipt rate at the time of the study did not differ between ASD (24.3%) and non-ASD groups (27.8%). Around two-thirds of parents of children with ASD refused or were unsure about vaccinating their children against COVID-19. We found that the intent to vaccinate against COVID-19 was higher in parents who were married and in those with a lower PACV total score. Continued public health efforts are needed to address vaccine hesitancy among parents.

Identifying gaps in vaccination perception after mandating the COVID-19 vaccine in Saudi Arabia.

OBJECTIVE: The burden of COVID-19 pandemic affected the globe, and it is unclear how it has impacted the general perception of other vaccines. We aimed to investigate the public awareness, knowledge, and attitude towards other complementary vaccines after the mandate of the COVID-19 vaccine. METHODS: A cross-sectional study was conducted in Saudi Arabia using a survey distributed via several social media platforms in June 2022. The questionnaire had three main sections; awareness; attitudes; and demographic information. Descriptive analysis was mainly used and supplemented with Chi-square test for correlation. All individuals over the age of 18 were eligible to participate in the study. RESULTS: A total of 1,045 participants from Saudi Arabia completed the survey. Of the respondents, 55.9% were female, and 95% were Saudi citizens. Public awareness towards vaccines after the mandate of COVID-19 vaccine was the highest with the influenza vaccine (98.2%), followed by human papillomavirus (HPV) (40.7%), tetanus, diphtheria, and pertussis (Tdap) (37.2%), and lastly, pneumococcal vaccine (17%). More than 50% of the participants expressed their willingness to receive any of the four vaccines if they knew about the benefits related to these vaccines. CONCLUSION: The study showed that participants were willing to receive the vaccination if they were aware of the general benefits of vaccinations. Therefore, health education and campaigns toward recommended vaccines for high-risk group are essential and needed.

Investigation of Alkali-Activated Slag-Based Composite Incorporating Dehydrated Cement Powder and Red Mud.

Recycled construction cementitious materials (RCCM) and red mud (RM) could be considered a type of discarded material with potential cementitious properties. Generally, landfilling and stacking are utilized to dispose of this type of solid waste, which can be detrimental to the environment and sustainability of the construction sector. Accordingly, a productive process for making eco-efficient alkali-activated slag-based samples with the inclusion of RCCM and red mud is studied in this paper. Dehydrated cement powder (DCP) is attained through the high-temperature treatment of RCCM, and red mud can be obtained from the alumina industry. Subsequently, DCP and RM are utilized as a partial substitute for granulated blast furnace slag (GBFS) in alkali-activated mixtures. Two different batches were designed; the first batch had only DCP at a dosage of 15%, 30%, 45%, and 60% as a partial substitute for GBFS, and the second batch had both DCP and RM at 15%, 30%, 45%, and 60% as a partial substitute for GBFS. Different strength and durability characteristics were assessed. The findings show that when both dehydrated cement powder and red mud are utilized in high quantities, the strength and durability of the specimens were enhanced, with compressive strength improving by 42.2% at 28 days. Such improvement was obtained when 7.5% each of DCP and RM were added. The results revealed that DCP and RM have a negative effect on workability, whilst they had a positive impact on the drying shrinkage as well as the mechanical strength. X-ray diffraction and micro-structural analysis showed that when the amount of DCP and RM is increased, a smaller number of reactive products forms, and the microstructure was denser than in the case of the samples made with DCP alone. It was also confirmed that when DCP and RM are used at optimized dosages, they can be a potential sustainable binder substitute; thus, valorizing wastes and inhibiting their negative environmental footprint.

Performance of Porous Asphalt Mixtures Containing Recycled Concrete Aggregate and Fly Ash.

This study investigates the effects of two waste materials from construction and industry, namely recycled concrete aggregate (RCA) and Type C fly ash, on the overall performance of a special type of pavement surface mixture, porous asphalt mixture. Mixtures of different combinations of RCA (for partial aggregate replacement) and fly ash (for filler replacement) were prepared in the laboratory and tested for a variety of pavement surface performance parameters, including air-void content, permeability, Marshall stability, indirect tensile strength, moisture susceptibility, Cantabro loss, macrotexture, and sound absorption. The analysis of the results showed that incorporating RCA or fly ash in a porous asphalt mixture slightly reduced the air-void content, permeability, and surface macrotexture of the mixture. A 10% replacement of granite aggregates with RCA in the porous asphalt mixtures led to a reduction in mixture stability, indirect tensile strength, resistance to raveling, and sound absorption. The further substitution of mineral filler with fly ash in the mixture, however, helped to offset the negative impact of RCA and brought the mechanical properties of the mixture with 10% RCA to levels comparable to those of the control mixture.

Severe Rheumatic Mitral Stenosis, Worse Left Atrial Mechanics is Closely Associated with Echo Criteria for Intervention.

Background: Rheumatic mitral valve (MV) stenosis is associated with progressive left atrial (LA) fibrosis and functional impairment, Pulmonary artery systolic pressure (PASP) and right ventricular (RV) dysfunction. The aims of the study were to determine in those patients with severe MV stenosis if LA mechanical function as assessed by speckle tracking echocardiography could identify those with increased PASP, atrial fibrillation (AFib), and RV dysfunction. Subjects and Methods: Patients with severe MV stenosis were identified from the institutional echo database. Echocardiograms were read off line and measurements included atrial and ventricular strain. Patients were divided into tertiles of LA reservoir strain (LASr) values and data compared between the groups. Results: Ninety-seven patients, 67 females, mean age 47.4 ± 11.9 years, had MV mean gradient of 8.3 ± 5.1 mmHg, MV area by pressure half time of 1.3 ± 0.3 cm2 and LASr of 11.18% ± 6.4%. Those patients in the lowest LASr tertile had more AFib (72%, P = 0.0001), PASP >50 mm Hg (39%, P = 0.005), and worst RV impairment. In multivariable logistic regression analysis, LASr, age, and mean MV gradient were the independent predictors of AFib and PASP >50 mm Hg. Cutoffs, determined by receiver operating characteristic curve analysis had high specificity for the composite outcome of Afib and PASP >50 mmHg (85% for LASr <7.7%). Conclusion: In severe MV stenosis LASr, age and mean MV gradient, are independent predictors of Afib and PASP >50 mmHg. LASr <7.7% has high sensitivity and specificity in identifying those who meet ESC guideline 2017 criteria for valve intervention, suggesting its potentially helpful addendum to the surveillance of patients with MV stenosis.