Effect of homogeneous ceramic tile waste on properties of mortar

The subject of reduce, reuse and recycle of waste material either from industrial or agricultural sectors is considered very important in the general attempt for sustainable construction. In relation to that, ceramic materials are widely used in many part of the world and consequently, large quantities of wastes are produced simultaneously by brick and tile manufacturers and construction industry. However, part of these wastes and those produced by the construction industry are dumped in landfills. In this present research, the effect of homogeneous ceramic tile waste on harden properties of mortar was investigated. Mortar mixes were prepared focusing on the effect of ceramic aggregates as river sand replacement. Tests were conducted for compressive strength, splitting tensile strength for all mortar specimens. The cement was partially replaced by ceramic powder by 20 %, 40 % and 60 %, respectively by weight of cement. The sand was replaced by ceramic aggregates ranging from 0% to 100% by weight of aggregates. The size of ceramic aggregates used is modified in accordance with ASTM C-33 while the cement was partially replaced by 40 % of ceramic powder by weight of cement. All specimens were cast in 50 mm cubes and cured in water after demoulding until the age of testing. By replacing 100 % of sand with ceramic aggregates, it was found that the compressive strength was very much similar to the control specimen without showing any negative effect. Similarly, by replacing cement with ceramic powder, the strength of mortar shows 10% increment as compared to control specimen. In conclusion, incorporation of homogenous ceramic tile waste either as sand replacement or cement replacement both can enhance the properties of mortar in fresh and hardened states

Long term studies on compressive strength of high volume ultrafine palm oil fuel ash mortar mixes

The long term characteristics of nano palm oil fuel ash in the mortar were investigated. This study covers basic properties like the morphology, porosity, compressive strength and microstructure properties with regards to the variations in the mix design process of mortar. To get a better performance in terms of strength development, the ash used has gone through heat treatment and was ground up to nano size. The mortar mixes were cast in 70x70x70mm cubes for compressive strength test. The incorporation of more than 80% nano size palm oil fuel ash as cement replacement has produced a mortar having a compressive strength more than OPC mortar at a later age. By treating the palm oil fuel ash to nano size, help reduce the cost of expensive admixture for improving the compressive strength of mortar. The results also revealed that the compressive strength of mortar using nano size palm oil fuel ash shows higher value as compared to initial strength at the later age of 1 year by 25%. The porosity of 80% nano palm oil fuel ash mortar reduced 51% as the age of curing increased. The overall results have revealed that the inclusion of high volume nano palm oil fuel ash can produce a mortar mix with high strength, low porosity, good quality and most importantly that is more sustainable

Laboratory and numerical investigation on strength performance of inclined pillars

Pillars play a critical role in an underground mine, as an inadequate pillar design could lead to pillar failure, which may result in catastrophic damage, while an over-designed pillar would lead to ore loss, causing economic loss. Pillar design is dictated by the inclination of the ore body. Depending on the orientation of the pillars, loading can be axial (compression) in horizontal pillars and oblique (compression as well as shear loading) in inclined pillars. Empirical and numerical approaches are the two most commonly used methods for pillar design. Current empirical approaches are mostly based on horizontal pillars, and the inclination of the pillars in the dataset is not taken into consideration. Laboratory and numerical studies were conducted with different width-to-height ratios and at different inclinations to understand the reduction in strength due to inclined loading and to observe the failure mechanisms. The specimens’ strength reduced consistently over all the width-to-height ratios at a given inclination. The strength reduction factors for gypsum were found to be 0.78 and 0.56, and for sandstone were 0.71 and 0.43 at 10? and 20? inclinations, respectively. The strength reduction factors from numerical models were found to be 0.94 for 10? inclination, 0.87 for 20? inclination, 0.78 for 30? inclination, and 0.67 for 40? inclination, and a fitting equation was proposed for the strength reduction factor with respect to inclination. The achieved results could be used at preliminary design stages and can be verified during real mining practice

An Effiecient Approach for Resource Auto-Scaling in Cloud Environments

Cloud services have become more popular among users these days. Automatic resource provisioning for cloud services is one of the important challenges in cloud environments. In the cloud computing environment, resource providers shall offer required resources to users automatically without any limitations. It means whenever a user needs more resources, the required resources should be dedicated to the users without any problems. On the other hand, if resources are more than user’s needs extra resources should be turn off temporarily and turn back on whenever they needed. In this paper, we propose an automatic resource provisioning approach based on reinforcement learning for auto-scaling resources according to Markov Decision Process (MDP). Simulation Results show that the rate of Service Level Agreement (SLA) violation and stability that the proposed approach better performance compared to the similar approaches

Polysubstance-induced relapse of schizoaffective disorder refractory to high-dose antipsychotic medications: a case report

BACKGROUND: The high prevalence of comorbid illicit drug use in persons with chronic psychotic illness represents a strong determinant of psychotic relapse and rehospitalization. Epidemiological studies indicate changing patterns of illicit drug use in Australia, which are concerning because of increased use of crystal methamphetamine, also known as "ice." An important complication of habitual use of crystal methamphetamine is the development of a dose-dependent acute psychotic reaction. We report a case of an acute psychotic relapse in response to polydrug use most notable for multiple recent binges of crystal methamphetamine. Unlike previously described case reports, our patient\u27s acute psychosis was refractory to ultra-high doses of multiple antipsychotic medications. This presented safety challenges due to the risk of serious side effects with high-dose antipsychotic medications.CASE PRESENTATION: A 30-year-old white man with a past history of schizoaffective disorder was brought to our emergency department by the police in a state of extreme agitation, combativeness, and paranoia after use of cannabis and crystal methamphetamine. Despite existing compliance with zuclopenthixol decanoate depot medication, he required multiple emergency injections of zuclopenthixol acetate, and regular high-dose droperidol, chlorpromazine, and lorazepam. However, he remained severely agitated and psychotic with continuous threats of harm to others. A test of antipsychotic drug metabolism by cytochrome P450 enzymes did not reveal a pharmacogenetic cause for the poor therapeutic efficacy of antipsychotic medications. His psychosis did not appear to be modified by psychoactive medications but was instead self-limited to the presence of endogenous methamphetamine within his system. He fully recovered 96 to 120 hours post-presentation and was discharged home with out-patient clinic follow-up.CONCLUSIONS: The current case highlights the challenging nature of a severe psychotic relapse precipitated by illicit substances that is resistant to medical management. High doses of multiple antipsychotic medications may be required to manage dangerous behaviors associated with these acute psychotic relapses. These patients require close monitoring for adverse effects with adjustment of dosing to ensure the optimal balance of risk versus benefit while the patient is acutely psychotic. The results are of relevance for the management of psychiatric emergencies in emergency departments and acute mental health settings

Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

Effects of steel fibres on concrete properties and flexural behaviour of reinforced concrete slabs

Concrete is a material that is good in compression but weak in tension. Enhancing the tensile properties of concrete will lead to its greater application in construction. It was reported that improvement on the mechanical properties of reinforced concrete structure can be achieved by the inclusion of short fibres. The use of short steel fibres have been reported to increase the toughness, abrasion, impact resistances and allow for decrease in concrete slab thickness. This paper focuses on the study conducted in the laboratory on the effect of steel fibre on concrete properties and behaviour of steel fibre reinforced concrete slabs under flexure with different amount of tensile reinforcements. A number of concrete cubes and prisms with and without steel fibres, 0%, 0.5%, 1.0%, 1.5% and 2.0% together with four reinforced concrete slabs having different amount of tensile reinforcement were cast and tested to failure in flexure. The optimum dosage of steel fibre to be included in concrete slab was 1%. The reinforced concrete slabs manufactured consist of slab with tensile reinforcement bar of R-150 as control slab, slab with tensile reinforcement bar of R-300 and 1% dosage of steel fibres, slab with 1% dosage of steel fibres without tensile reinforcement, and one plain concrete slab without reinforcement. All the slabs cast having the overall dimensions of 100 x 500 x 1000 mm, and tested to failure under four point loading. Cube compressive strength, modified compressive strength, flexural strength, ultrasonic pulse velocity test and rebound hammer test were conducted. The behaviour of the reinforced concrete slabs was studied through their ultimate load, load-deflection characteristic upon loading, cracking history, and mode of failure. The experimental results show that the inclusion of steel fibres was found to improve the compressive strength, slightly lowered the UPV value but no significant effect on the rebound hammer compared to the control sample. It was also found that based on slab SB-R300-1SF the inclusion of steel fibres increased the ultimate load of the slab by 25%, reduce the tensile reinforcement by about 50%, improve the flexural stiffness and ductility of the slab when compared to the control slab, SC-R150

Hepatitis B surface antigen prevalence in pregnant women before and after national vaccinations

Background. Hepatitis B in pregnant mothers can pose a risk to both the mother and the baby. If left untreated or undiagnosed, hepatitis B can be passed from mother to child during childbirth, leading to chronic hepatitis B infection in the baby. However, with proper prenatal care, including testing and vaccination, the risk of transmission can be significantly reduced. This study investigates the hepatitis B surface antigen (HBsAg) prevalence in pregnant women before and after the start of the national hepatitis B vaccination plan. Materials and methods. This cross-sectional study was conducted on all pregnant mothers in Babol County who gave birth between 2018 and 2020. Then the mothers’ information, including a history of vaccination, place of residence, and HBsAg status, was recorded and checked through the online system and their health records. The obtained data were analyzed using SPSS software version 22 and were displayed as frequency and percentage. Qualitative variables were analyzed with Chi-square tests. Finally, with the logistic regression model, we investigated the effect of variables on hepatitis. In all tests, P-value less than 0.05 is significant. Results. The prevalence of positive HBsAg among 11 282 pregnant women in Babol city was 61 (0.5%). The prevalence rate among vaccinated and unvaccinated mothers was 8 (0.2%) and 53 (0.7%), respectively, and this difference was statistically significant (p = 0.001). The Prevalence of positive HBsAg among city and village residents was 26 people (0.4%) and 35 people (0.7%), respectively, and this difference was not significant (p = 0.07). Also, rural (p = 0.02, OR = 1.82, 95%CI: 1.08–302) and unvaccinated (p 0.001, OR = 3.79, 95%CI: 1.79–8.01) mothers had a higher chance of contracting hepatitis B. Conclusion. The results indicated that national hepatitis B vaccination in newborns has notably decreased infection rates in future childbearing women. Hepatitis B is a preventable disease through vaccination. The vaccine has demonstrated both safety and high immunogenicity. It is crucial to maintain the immunization of newborns and adhere to the screening guidelines for pregnant mothers as outlined in the national program