The effect of aspect ratio and volume fraction on mechanical properties of steel fibre-reinforced oil palm shell concrete

The utilization of oil palm shell (OPS) as a replacement for conventional coarse aggregate produces a greener structural lightweight aggregate concrete (LWAC). Steel fibres enhance the mechanical properties of LWAC including OPS concrete (OPSC). This paper reports on the influence of the aspect ratio (l/d) and volume fraction (Vf) of hooked end steel fibres in oil palm shell fibre-reinforced concrete (OPSFRC). The fresh and hardened concrete properties, including ultrasonic pulse velocity (UPV) and post-failure compressive strength (PFCS) of ten mixes with three each for l/d (55, 65 and 80) and Vf (0.25%, 0.5% and 0.75%) are investigated. The mix with an l/d of 65 produced the highest values of slump, density, and compressive strength. The enhancement in the splitting tensile strength of 83% compared to the control mix was obtained for the mix with the highest l/d. Generally, the increase in Vf from 0.25% to 0.75% improved the mechanical properties. The UPV results indicated that all OPSFRC and PFCS of 66–70% obtained were of good quality. First published online: 24 Aug 201

Ductile behaviour of oil palm shell concrete slabs subjected to blast loads

Oil palm shell (OPS) is an industrial waste material abundantly available in Malaysia and other South East Asian countries. It has high aggregate impact resistance characteristics and hence its capability to withstand blast load was tested through OPS concrete (OPSC) slabs designed and developed in University of Malaya, Kuala Lumpur, Malaysia and tested at Huluduo, China. LVDTs, pressure transducers and accelerometers were used to record data of response of the slabs subjected to quasi-static load and blast loads of 1, 5 and 10 kg TNT. The recorded data were then analysed and compared and conclusions were made on the effectiveness of OPS as a coarse aggregate. It has been found that OPSC outperformed normal concrete (NC) slab when subjected to 10 kg TNT as OPSC panel was intact and had no shrapnel; the ductility behaviour of OPSC, it exhibited multiple cracks and the impact resistance of OPS through its energy absorption due to fibrous content within OPS itself was visible both in crack pattern and in its propagation. Though OPS is of organic nature, its resistance to blast waves was observed as the huge fire ball created due to blast had no or little effect on the OPSC panels

Prevalence of Severe Anxiety among Elective Caesarean Section Mothers and their Perceived Complications of Anaesthesia in Malaysia

Introduction: Many women experience psychological problems during pregnancy. One of the major psychological problems is anxiety. Pregnancy related anxiety can lead to various negative effects not only on mother’s health, but also on their socio-dynamic factors as well as the infant’s development. Preoperative anxiety among obstetric patients is known to be much higher compared to other surgical patients. Aim: In this study we assessed the prevalence of severe anxiety among elective caesarean section mothers and their perceived complications of anaesthesia in Malaysia. Method: This study was conducted among 280 pregnant women in the obstetrics and gynaecology department in a tertiary hospital in Malaysia. The pregnant women’s level of anxiety was assessed using the 20-item S-anxiety scale, preoperative and postoperative. Results: Pre-operative, out of the 280 respondents, 70 (25%) were classified as having severe anxiety. Among those with previous SVD, 41.7% had severe level of anxiety compared to only 21.2% among those with previous LSCS (p=0.008). At post-operative assessment, 27 (9.6%) were classified as having severe anxiety. Overall, there was a significant reduction in the level of anxiety from pre to post operative (p <0.001). The perceived complications from general anaesthesia were death (34.3%), coma (32.1%) and postoperative pain (30%) and the perceived complications from regional anaesthesia were back pain (27.9%) and paralysis (27.9%). Conclusion: Preoperative anxiety in women undergoing caesarean section is high. Preoperative anxiety should be evaluated for further planning of coping strategies to overcome their anxiety and fear

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

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

Pooled analysis of WHO Surgical Safety Checklist use and mortality after emergency laparotomy

Background The World Health Organization (WHO) Surgical Safety Checklist has fostered safe practice for 10 years, yet its place in emergency surgery has not been assessed on a global scale. The aim of this study was to evaluate reported checklist use in emergency settings and examine the relationship with perioperative mortality in patients who had emergency laparotomy. Methods In two multinational cohort studies, adults undergoing emergency laparotomy were compared with those having elective gastrointestinal surgery. Relationships between reported checklist use and mortality were determined using multivariable logistic regression and bootstrapped simulation. Results Of 12 296 patients included from 76 countries, 4843 underwent emergency laparotomy. After adjusting for patient and disease factors, checklist use before emergency laparotomy was more common in countries with a high Human Development Index (HDI) (2455 of 2741, 89.6 per cent) compared with that in countries with a middle (753 of 1242, 60.6 per cent; odds ratio (OR) 0.17, 95 per cent c.i. 0.14 to 0.21, P <0001) or low (363 of 860, 422 per cent; OR 008, 007 to 010, P <0.001) HDI. Checklist use was less common in elective surgery than for emergency laparotomy in high-HDI countries (risk difference -94 (95 per cent c.i. -11.9 to -6.9) per cent; P <0001), but the relationship was reversed in low-HDI countries (+121 (+7.0 to +173) per cent; P <0001). In multivariable models, checklist use was associated with a lower 30-day perioperative mortality (OR 0.60, 0.50 to 073; P <0.001). The greatest absolute benefit was seen for emergency surgery in low- and middle-HDI countries. Conclusion Checklist use in emergency laparotomy was associated with a significantly lower perioperative mortality rate. Checklist use in low-HDI countries was half that in high-HDI countries.Peer reviewe

Global variation in anastomosis and end colostomy formation following left-sided colorectal resection

Background End colostomy rates following colorectal resection vary across institutions in high-income settings, being influenced by patient, disease, surgeon and system factors. This study aimed to assess global variation in end colostomy rates after left-sided colorectal resection. Methods This study comprised an analysis of GlobalSurg-1 and -2 international, prospective, observational cohort studies (2014, 2016), including consecutive adult patients undergoing elective or emergency left-sided colorectal resection within discrete 2-week windows. Countries were grouped into high-, middle- and low-income tertiles according to the United Nations Human Development Index (HDI). Factors associated with colostomy formation versus primary anastomosis were explored using a multilevel, multivariable logistic regression model. Results In total, 1635 patients from 242 hospitals in 57 countries undergoing left-sided colorectal resection were included: 113 (6·9 per cent) from low-HDI, 254 (15·5 per cent) from middle-HDI and 1268 (77·6 per cent) from high-HDI countries. There was a higher proportion of patients with perforated disease (57·5, 40·9 and 35·4 per cent; P < 0·001) and subsequent use of end colostomy (52·2, 24·8 and 18·9 per cent; P < 0·001) in low- compared with middle- and high-HDI settings. The association with colostomy use in low-HDI settings persisted (odds ratio (OR) 3·20, 95 per cent c.i. 1·35 to 7·57; P = 0·008) after risk adjustment for malignant disease (OR 2·34, 1·65 to 3·32; P < 0·001), emergency surgery (OR 4·08, 2·73 to 6·10; P < 0·001), time to operation at least 48 h (OR 1·99, 1·28 to 3·09; P = 0·002) and disease perforation (OR 4·00, 2·81 to 5·69; P < 0·001). Conclusion Global differences existed in the proportion of patients receiving end stomas after left-sided colorectal resection based on income, which went beyond case mix alone

Effect of fiber in enhancement of mechanical properties and structural behaviors of oil palm shell concrete / Yap Soon Poh

The significance contribution of utilizing locally available waste materials to replace conventional concrete materials gained considerable attention during the past two decades in the realization of sustainable building materials. One such industrial waste material available abound in South East Asia is lightweight oil palm shell (OPS). Earlier researches on OPS showed that OPS could be considered as an ideal replacement of granite aggregates to produce a sustainable lightweight concrete called oil palm shell concrete (OPSC). The development of OPSC has the advantage as a lightweight concrete in addition to environmental benefits. However, the application of OPSC in structural members is less convincing due to its low tensile strength and the addition of fibers has been effective to solve this weakness. The initial challenge in the development of oil palm shell fiber reinforced concrete (OPSFRC) lies in selection of appropriate fibers. In this study, fibrillated and monofilament fibers, nylon fibers and steel fibers of aspect ratio 55, 65 and 80 were added in the OPSC to investigate the effects of different fibers on the mechanical properties of OPSFRC and thereby to select the suitable type of fiber. This would enable to study the effect of volume fraction of fibers on the mechanical properties and structural behaviors under flexural and torsion. In addition, by using a high volume fraction of 3% of steel fibers was added in OPSC to further enhance the tensile strength of OPSFRC to be applied as structural members for special usage which requires high tensile strength. The high tensile strength OPSFRC was tested for mechanical properties, toughness and flexure beam testing. The results show that the synthetic fibers including polypropylene and nylon fibers produced slight increments on the mechanical properties of OPSFRC without significant changes in density. On contrary, steel fibers of aspect ratio 65 outperformed other fibers to produce the highest compressive and flexural strength of 47 MPa and 7 MPa, respectively. Therefore steel fiber of aspect ratio 65 with amount up to 1% was added in the OPSC beams to investigate the flexural and torsional behaviors of OPSFRC beams. The experimental results reported that the increase in the fiber volume resulted in a higher enhancement of the flexural, torsional and cracking resistance of the OPSFRC beams. The OPSFRC beams reinforced with 1% steel fiber show significant increment in flexural and torsional toughness compared to the plain OPSC specimens. OPSFRC beam with 3% steel fibers produced high tensile strength with flexural strength of 18 MPa. The flexural behaviors of high tensile strength OPSFRC showed drastic improvement in moment capacity and cracking resistance compared to OPSFRC beam with 1% steel fiber. It can be concluded that the addition of steel fiber up to 3% enabled the production of high tensile strength OPSFRC which is suitable for structural application

Delay Factors Management and Ranking for Reconstruction and Rehabilitation Projects Based on the Relative Importance Index (RII)

In recent decades, the construction industry has developed rapidly. Delay was and remains one of the most important challenges negatively affecting not only this industry but also the economy and sustainable development. This study aims to conduct a comprehensive analysis of the delay factors in reconstruction projects because of the vital importance of these types of projects. This is the first attempt to conduct such an analysis for reconstruction projects in particular, and it is a continuation of the previous case study, which was considered one of the most important reconstruction projects in the Middle East region. The previous study focused on determining the types of delay factors used in this project. It is necessary to carry out advance in-depth analysis to sort the delay factors based on their effect on the project plan. In order to achieve the study goal, 93 questionnaires were distributed by hand to experts working on the project: some of them working the day shift, and the others working the night shift. The questionnaire results were analyzed and delay factors were sorted in descending order according to the relative importance index (RII). The three main factors affecting the overall reconstruction project duration were site restrictions and conditions, electrical and mechanical rerouting works, and design buildability and adjustment

Delay Factors in Reconstruction Projects: A Case Study of Mataf Expansion Project

Delays in construction projects are a common phenomenon throughout the industry. This problem has many negative impacts on the time, cost, and sustainability of the projects. Many studies were conducted to identify the main causes of this delay in new construction projects in different regions but very few studies have focused on finding an explanation for the causes of delay in major reconstruction projects that have great religious and cultural sustainability. This paper examines the factors that contributed to work delays in one of the most major reconstruction projects that took place recently in the Middle East, which is namely the Mataf Expansion Project in the city of Mecca, Saudi Arabia. Fourteen interviews were conducted with project managers, construction managers, and senior site engineers to identify the factors that they encountered and led to the delay in the reconstruction activities of this project. Some of the findings were consistent and similar to most other causes of delay that are associated with new construction projects. However, interestingly, this research has discovered the existence of other unavoidable factors that caused a delay and should be considered for any similar reconstruction projects. The results showed that these factors could be divided into two groups: the first one is related to the demolition phase (five factors) and the second group is related to construction works (nine factors). In addition, it has been observed that the building material during the reconstruction is considered one of the major delaying factors. Finally, these 14 delay factors should be carefully considered to assure the sustainability of the main object&#8217;s function during the reconstruction activities