98 research outputs found
Colorectal carcinoma associated with schistosomiasis: a possible causal relationship
The association between schistosomiasis and colorectal malignancy has long been suggested in the literature, but it is not uniformly accepted. In the Far East, considerable evidence supports an etiological link between Schistosoma japonicum and colorectal cancer. However, the available data regarding the role of Schistosoma mansoni in colorectal carcinogenesis are conflicting and most often do not show causality. We report on a patient with sigmoid colonic cancer coexisting with schistosomiasis, and we provide a comprehensive review of the literature regarding the epidemiology and pathobiology of this association
Performance of RHA Cement Concrete under Marine Environment via Wetting and Drying Cyclic by Rapid Migration Test
In this research, the performance of concrete containing rice husk ash (RHA) under marine environment through wetting and drying cycles was investigated. Five levels of cement replacement (0%, 10%, 20%, 30% and 40% by weight) were used. The total cementitious content used was 420 kg/m3. A water/binder ratio of 0.49 was used to produce concrete having a target compressive strength of 40MPa at the age of 28 days. The performance of blended cement concrete under marine environment was evaluated using rapid migration test (RMT). The results clearly showed that RHA can be satisfactorily used as a cement replacement material in order to reduce the chloride penetration depth and hence increases the durability of concrete. Generally, the chloride penetration depth of concrete containing higher RHA replacement is decreased as the RHA replacement increases, resulting in concrete with higher resistance to seawater attack
Channel estimation for MIMO-OFDM systems based on data nulling superimposed pilots
This paper proposes a new channel estimation algorithm based on data nulling superimposed pilots for the spatial multiplexing multiple-input-multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) systems. In the proposed method each OFDM data symbol of each transmit antenna is spread over all subcarriers by using a spreading matrix then nulls are introduced at certain subcarriers to cancel the mutual interference between data symbols and superimposed pilots. At receiver accurate channel estimation can be easily acquired based on the superimposed pilots. Then the superimposed pilots are removed from the received signal and simple iterative data detection scheme is used to compensate the distortion which occurred in the data symbols. The simulation results of the proposed algorithm show improvement in the estimation accuracy, bit error rate (BER) and computational complexity compared to that of the conventional superimposed pilot technique. The simulation results also show that the performance of the proposed technique approaches that of the frequency division multiplexed pilots technique while having higher data rate and some excess in the receiver complexity
Transformational leadership and job involvement in the Middle East: the moderating role of individually held cultural values
This study examines whether individually held cultural values moderate the relationship between transformational leadership behavior of supervisors and the job involvement of subordinates in the Middle Eastern organizational context. Hierarchical regression analysis was used to analyze survey data from 229 employees of 10 organizations in the United Arab Emirates. In line with the findings of studies in Western countries, transformational leadership was found to influence job involvement positively. In addition, the cultural value orientations of individuals were found to moderate this relationship. Collectivism positively influenced the relationship between transformational leadership and job involvement, whereas uncertainty avoidance had a negative effect. These findings provide an insight into how transformational leadership may be used to motivate culturally diverse groups of employees within the Middle East. To enhance job involvement, organizations need to realize that the attitudinal response of subordinates to transformational leadership can depend on their cultural values. This has significant implications regarding the training and effective deployment of transformational leaders within Middle Eastern organizations
Maladie de Crohn colique et psoriasis : une association rare
Le psoriasis et la maladie de Crohn (MC) font partie des maladies inflammatoires chroniques à médiation immunitaire. Les liens nosologiques, génétiques, immunologiques et les facteurs environnementaux qui les influencent sont très semblables. L’atteinte cutanée représente la manifestation extradigestive la plus habituelle de la MC, parfois inaugurale. Le pyoderma gangrenusum, l’aphtose et l’érythème noueux sont fréquemment décrits, le psoriasis en est très rarement associé. Nous rapportons une observation de psoriasis associé à la MC. L’intérêt de notre travail est de décrire une association rare, ainsi que les particularités de sa prise en charge
Development of rainfall-runoff modelling using the HEC-HMS at the catchment of Kelantan River, Malaysia
The simulation of rainfall-runoff is important to be analysed at the Kelantan River catchment as flood is one of the common natural disasters in Kelantan. Sustainable water management in this region is only feasible following the availability of reliable information on the rainfall-runoff and other hydrological determinants that affect the water system. This study aims to evaluate the effects of extreme rainfall on the runoff at the catchment of the Kelantan River where recurrent floods have been occurring since 1988 to 2019. The study employs the remote sensing and geographic information system (GIS) integrated with the Hydrologic Engineering Center-Hydrologic Modelling Systems (HEC-HMS) to delineate the catchment line and simulate the river discharge. The observed discharge is used during the calibration and validation process to evaluate the performance of the integrated model. The model performed satisfactorily by obtained R2 with the range of 0.80-0.97 and 0.64-0.93 in each sub-catchment during the calibration and validation period. The finding indicates that the developed HEC-HMS model has the ability to simulate event-based runoff
Numerical simulation of flow within a storage area of HDPE modular pavement
The development of stromwater management usually promote to provide the safe passage of stromwater. However physical modelling need expensive laboratory experiments. Due to that this numerical study is performed to study the flow within storage area of HDPE modular pavement. This paper studied and compared the infiltration rate of diagonal modular and conventional pavement (control), determined the velocity magnitude and pressure of modular pavement at various rainfall intensities. FLOW-3D was used to run a simulation on a porous media flow model using the Navier-Stokes equation. Real rainfall data of Malaysia was used as the model inputs to get better analysis of pavement design. The present findings showed that storage area modular pavement has lower fraction of fluid than control, which means that it has greater holding capacity and capable to capture all the rainfall volume from 5mm/h to 85mm/h. Besides, rainfall intensity has a strong influence on velocity magnitude and pressure. The HDPE diagonal modular pavement strong enough to sustain with an increasing of velocity magnitude and pressure during extreme rainfall. Therefore, HDPE modular pavement indicates a better water interception capacity than conventional pavement. FLOW-3D helps the critical analysis of pavement design process and useful as supplementary tool
Spermatozoal Fractalkine Signaling Pathway Is Upregulated in Subclinical Varicocele Patients with Normal Seminogram and Low-Level Leucospermia
Background. Fractalkine is produced in seminal plasma in small amounts and correlates with sperm motility. Purpose. To investigate the possible effect of low-level leucospermia on spermatozoa oxidative stress and sDNA fragmentation in patients with subclinical varicocele and apparently normal seminogram, and also to study the role of spermatozoal fractalkine and its receptor (CX3CR1) gene expression as a marker of spermatozoa inflammatory response. Methods. This study included 80 patients with subclinical varicocele (45 fertile and 35 infertile) and 45 age-matched fertile volunteers. In semen samples, fractalkine and CX3CR1 gene expression were investigated by qRT-PCR. Moreover, seminal plasma malondialdehyde (MDA) and total antioxidant capacity (TAC) were measured. Results. There are significant decrease in semen quality and significant increase in seminal leucocytes count in subclinical varicocele. Our results show a significant increase in MDA and TAC levels, DNA fragmentation, and expression levels of fractalkine and its receptor (CX3CR1) in subclinical varicocele groups. Conclusion. Subclinical varicocele induces seminal and spermatozoal subclinical inflammatory response in the form of low-level leucospermia and increased mRNA expression of the fractalkine signaling pathway, leading to increased spermatozoal ROS production, oxidative stress, and DNA fragmentation. These could cooperate in the pathogenesis of delayed fertility in males with subclinical varicocele
Incidence of nonvalvular atrial fibrillation and oral anticoagulant prescribing in England, 2009 to 2019: A cohort study.
BACKGROUND: Atrial fibrillation (AF) is an important risk factor for ischaemic stroke, and AF incidence is expected to increase. Guidelines recommend using oral anticoagulants (OACs) to prevent the development of stroke. However, studies have reported the frequent underuse of OACs in AF patients. The objective of this study is to describe nonvalvular atrial fibrillation (NVAF) incidence in England and assess the clinical and socioeconomic factors associated with the underprescribing of OACs. METHODS AND FINDINGS: We conducted a population-based retrospective cohort study using the UK Clinical Practice Research Datalink (CPRD) database to identify patients with NVAF aged ≥18 years and registered in English general practices between 2009 and 2019. Annual incidence rate of NVAF by age, deprivation quintile, and region was estimated. OAC prescribing status was explored for patients at risk for stroke and classified into the following: OAC, aspirin only, or no treatment. We used a multivariable multinomial logistic regression model to estimate relative risk ratios (RRRs) and 95% confidence intervals (CIs) of the factors associated with OAC or aspirin-only prescribing compared to no treatment in patients with NVAF who are recommended to take OAC. The multivariable regression was adjusted for age, sex, comorbidities, socioeconomic status, baseline treatment, frailty, bleeding risk factors, and takes into account clustering by general practice. Between 2009 and 2019, 12,517,191 patients met the criteria for being at risk of developing NVAF. After a median follow-up of 4.6 years, 192,265 patients had an incident NVAF contributing a total of 647,876 person-years (PYR) of follow-up. The overall age-adjusted incidence of NVAF per 10,000 PYR increased from 20.8 (95% CI: 20.4; 21.1) in 2009 to 25.5 (25.1; 25.9) in 2019. Higher incidence rates were observed for older ages and males. Among NVAF patients eligible for anticoagulation, OAC prescribing rose from 59.8% (95% CI: 59.0; 60.6) in 2009 to 83.2% (95% CI: 83.0; 83.4) in 2019. Several conditions were associated with lower risk of OAC prescribing: dementia [RRR 0.52 (0.47; 0.59)], liver disease 0.58 (0.50; 0.67), malignancy 0.74 (0.72; 0.77), and history of falls 0.82 (0.78; 0.85). Compared to white ethnicity, patients from black and other ethnic minorities were less likely to receive OAC; 0.78 (0.65; 0.94) and 0.76 (0.64; 0.91), respectively. Patients living in the most deprived areas were less likely to receive OAC 0.85 (0.79; 0.91) than patients living in the least deprived areas. Practices located in the East of England were associated with higher risk of prescribing aspirin only over no treatment than practices in London (RRR 1.22; 95% CI 1.02 to 1.45). The main limitation of this study is that these findings depends on accurate recording of conditions by health professionals and the inevitable residual confounding due to lack of data on certain factors that could be associated with under-prescribing of OACs. CONCLUSIONS: The incidence of NVAF increased between 2009 and 2015, before plateauing. Underprescribing of OACs in NVAF is associated with a range of comorbidities, ethnicity, and socioeconomic factors, demonstrating the need for initiatives to reduce inequalities in the care for AF patients
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
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