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The switch from petro-diesel fuel to biodiesel blends for Compression Ignition engines have raised tribological performance concerns among major automobile manufacturers. Biodiesel dilution on engine lubricants could have adverse long-term effects on the engine efficiency, which will reduce the fuel economy, thus, leading to higher greenhouse gas emissions. Therefore, this study investigates the tribological impact of palm methyl ester (PME) diluted in SAE5W40 and SAE10W40 engine lubricants along different lubrication regimes under engine cold start condition. Through lubrication Stribeck curve analysis conducted using a pin-on-disc tribometer, coefficient of friction (CoF) for both engine lubricants showed parabolic maximum behaviour with increasing PME dilution. The CoF reduction beyond these peak values is attributed to the improved friction modifier effect from the now-dominant PME but with reduced load carrying capacity. An effective lubricant should possess both reasonable friction modifier effect and highest load carrying capacity in mitigating boundary friction. Hence, through the study, it could be deduced that the acceptable PME dilution threshold level for SAE5W40 is up to 17.5-vol%, while for SAE10W40 is between 28.0-vol% and 34.5-vol%. PME dilution levels beyond these thresholds could easily cause lubrication film rupture under high load, high shear rate conditions during application along the mixed to boundary lubrication regimes, inducing material wear. [ABSTRACT FROM AUTHOR]

Highlights: [•] We describe Δ(dinB-yafN)883(::kan), a novel dinB allele, referred to as ΔdinB883, a deletion that sensitizes E. coli cells to UV irradiation. [•] This UV radiation sensitivity is most acute in the early logarithmic phase of culture growth. [•] This UV radiation sensitivity is completely dependent upon a functional umuDC operon. [•] Sequencing reveals ΔdinB883 retains the proximal 161 nucleotides, i.e., 54 amino acids, of the wild-type sequence. [•] The ΔdinB883 mutant is hypothesized to produce a peptide of 83 amino acids, DinB883, that compromises UmuDC function. [ABSTRACT FROM AUTHOR]

Abstract: Flow diverters (FDs) are high density meshed stents designed to reduce blood flow into intra-cranial aneurysms. Though the FD is one of many intracranial aneurysm (IA) treatments, FD implantation may also result in the growth and rupture of residual aneurysms. The purpose of this research is to investigate the effect of FD implantation on IA hemodynamics. Computational fluid dynamics (CFD) was conducted to analyze dynamic and resistance forces after FD deployment. Simulation results for the successful case (patient A) showed that FD flow resistance force was higher than dynamic force. This indicated that the FD provided sufficient resistance to reduce flow into the aneurysm. As a result, flow velocity magnitude at the aneurysm neck was reduced by 95%. On the other hand, the flow velocity magnitude at the aneurysm neck was reduced by about 50% for the unsuccessful case (patient B). The reason was that the flow resistance force at the aneurysm neck section was calculated to be lower than the flow driving force. In order to completely occlude the aneurysm, a higher resistance FD stent is to be required to suppress the dynamic forces. Patient-specific hemodynamic simulations offer means of quantitative estimation FD treatment outcomes. [Copyright &y& Elsevier]

Abstract: We report a 73-year-old man presenting with bilateral leg numbness and weakness. Three spinal dural arteriovenous fistulae (SDAVF) were found after clinical deterioration post lumbar puncture (LP). This patient highlights the difficulties in the diagnosis and management of SDAVF, and the risks of LP. [Copyright &y& Elsevier]

Abstract: Public transport systems have been targets in several terrorist attacks, notably in recent years, resulting in tight security measures worldwide. However, individuals’ privacy and liberty often conflict with efforts towards safety and security, making it difficult to assess the implications of security measures balanced against the costs (e.g., citizens may be stopped, searched and asked to provide personal identification data to authorities without any particular reason). Henceforth, our research question asks, “to what extent would people sacrifice their right to privacy and liberty in exchange for potentially safer and more secure travel?” This paper uses a stated choice experiment to quantify individuals’ trade-offs between privacy and security within a real-life context, namely rail travel in the UK. Using a nationwide sample, the empirical analysis yields the importance of improvements in the security infrastructure and identifies areas of concern with regard to privacy and liberty controlling for travel related factors. Further, trade-offs across different security measures for rail travel are quantified in terms of individuals’ willingness-to-pay extra on top of the average ticket price. [Copyright &y& Elsevier]

By 2050, it is predicted that biofuels will provide 27% of total transport fuel and avoid around 2.1 Gt CO2 emissions per year when produced sustainably. Biodiesel is a renewable fuel that can be produced by trans-esterification in any climate using already developed agricultural practices. This paper aims to study various physical and chemical properties of biodiesel synthesized from edible and non-edible feedstocks. These feedstocks include Croton megalocarpus, Calophyllum inophyllum, Moringa (Moringa oleifera), palm (Elaeis guineensis) and coconut (Cocos nucifera). The physical and chemical properties of biodiesel-diesel blends were also presented. Furthermore, the regression analysis method was used to predict the properties of biodiesel blends. It has been found that blending of diesel with biodiesel has resulted in much improvement in kinematic viscosity, density, calorific value and oxidation stability. However, flash point and viscosity index decrease as the percentage of diesel increases. Moreover, the mathematical relationships developed in this study show a high regression values (R²) between properties and biodiesel-diesel blends. As a conclusion, it is believed that the outcome of this study gives the readers valuable results that help to predict the properties of biodiesel and its blends with diesel which are substantial parameters in the design of fuel system for biodiesel engine. [ABSTRACT FROM AUTHOR]

Summary: Background: Over half of childhood intracranial ependymomas occur in children younger than 5 years. As an adjuvant treatment, radiotherapy can be effective, but has the potential to damage the child''s developing nervous system at a crucial time—with a resultant reduction in IQ and cognitive impairment, endocrinopathy, and risk of second malignancy. We aimed to assess the role of a primary chemotherapy strategy in avoiding or delaying radiotherapy in children younger than 3 years with intracranial ependymoma. Methods: Between December, 1992, and April, 2003, we enrolled 89 children with ependymoma who were aged 3 years or younger at diagnosis, of whom nine had metastatic disease on pre-operative imaging. After maximal surgical resection, children received alternating blocks of myelosuppressive and non-myelosuppressive chemotherapy every 14 days for an intended duration of 1 year. Radiotherapy was withheld unless local imaging (ie, from the child''s treatment centre) showed progressive disease. Findings: 50 of the 80 patients with non-metastatic disease progressed, 34 of whom were irradiated for progression. The 5-year cumulative incidence of freedom from radiotherapy for the 80 non-metastatic patients was 42% (95% CI 32–53). With a median follow-up of 6 years (range 1·5–11·3), overall survival for the non-metastatic patients at 3 years was 79·3% (95% CI 68·5–86·8) and at 5 years 63·4% (51·2–73·4). The corresponding values for event-free survival were 47·6% (36·2–58·1) and 41·8% (30·7–52·6). There was no significant difference in event-free or overall survival between complete and incomplete surgical resection, nor did survival differ according to histological grade, age at diagnosis, or site of disease. In 47 of 59 (80%) patients who progressed, relapse resulted from local control only. The median time to progression for the 59 patients who progressed was 1·6 years (range 0·1–10·2 years). The median age at irradiation of the whole group was 3·6 years (range 1·5–11·9). For the 80 non-metastatic patients, the 23 who achieved the highest relative dose intensity of chemotherapy had the highest post-chemotherapy 5-year overall survival of 76% (95% CI 46·6–91·2), compared with 52% (33·3–68·1) for the 32 patients who achieved the lowest relative dose intensity of chemotherapy. Interpretation: This protocol avoided or delayed radiotherapy in a substantial proportion of children younger than 3 years without compromising survival. These results suggest, therefore, that primary chemotherapy strategies have an important role in the treatment of very young children with intracranial ependymoma. [Copyright &y& Elsevier]

Acute administration of high-dose testosterone in men with coronary artery disease improves endothelial function. [ABSTRACT FROM AUTHOR]

Aim: To assess differences in the exposure, teaching, knowledge, appreciation, and interest in interventional radiology (IR) between male and female doctors prior to specialisation and to identify potential predisposing factors to the gender inequality in interventional radiology.Materials and Methods: A prospective cross-sectional multicentre study was conducted using in-person and web-based distribution of a voluntary, anonymous questionnaire to junior doctors yet to commence specialisation at 11 health services across two Australian states.Results: Complete responses were provided by 333 junior doctors (21.9% response rate). Women were significantly less likely than men to consider a career in IR (13.1% versus 29.7%, p < 0.001). No other statistically significant gender disparities were identified, as both men and women reported low levels of prior teaching and exposure to IR, strong belief in the importance of IR, and suboptimal knowledge of IR.Conclusions: The gender gap amongst practising Australian interventional radiologists is perpetuated by a consistent gender gap in upcoming junior doctors' desire to pursue IR. This disparity exists despite junior doctors receiving the same exposure and opportunities in interventional radiology, possibly suggesting that preconceived stereotypes or psychosocial factors deter females from pursuing this procedural, male-dominated subspecialty. Future qualitative studies are required to confirm this hypothesis, in conjunction with prospective, experimental trials to determine whether changes in education, mentorship, and advocacy can promote gender equality. [ABSTRACT FROM AUTHOR]

Abstract: Earthworm, Dilong in Chinese, is a traditional Chinese medicine used to treat many diseases including tumors. To investigate whether the coelomic fluid of the earthworm Eisenia fetida inhibits viability and induces apoptosis of HeLa cells, MTT assay, AO/EB fluorescent staining method and DNA agarose electrophoresis were applied. The cytotoxicity of coelomic fluid on HeLa cell showed a concentration dependent manner after 48h treatment as detected by the MTT assay. Coelomic fluid (1mg/ml) exhibited toxic effects on HeLa cells with an inhibition rate of 84.22%, leading to cell lysis. The inhibition rates in 0.1mg/ml and 0.01mg/ml treatments were 10.24% and 2.99%, respectively. Morphological changes of typical apoptosis were observed by AO/EB staining in 0.1mg/ml and 0.01mg/ml concentration with apoptotic rates of 79.1% and 22.2%, while the cells were necrotic in 1mg/ml concentration as indicated by red stained cells. The agarose gel electrophoresis of DNA revealed a smear pattern at the concentrations of 0.1mg/ml and 0.01mg/ml of coelomic fluid. At the concentration of 0.1mg/ml, the coelomic fluid induced apoptosis in HeLa cells in a time dependent manner. This work suggests that some of the coelomic fluid components might be useful for pharmaceutical applications in the treatment of cancer, but our knowledge is still very limited. Testing this hypothesis will require intense controlled investigations. [Copyright &y& Elsevier]