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Throughout the history of power systems, power cables have been used to securely and efficiently distribute electrical energy to the destined locations. Cross-linked polyethylene (XLPE), a commonly used insulator in high-voltage cables, have several desirable properties, such as low dielectric loss, high dielectric constant, high thermal conductivity, enhanced thermal stability, and superior resistance against electrical stress. However, further improvements of XLPE's performance are needed. The incorporation of large specific surface area nanoparticles, such as boron nitride nanosheets and graphene oxide, exhibited a great potential in enhancing XLPE's properties. These nanoparticles create numerous trapping sites, even at small loading levels, due to their large interfacial regions. In addition, voltage stabilisers with polar groups can scavenge high-energy electrons generated by local electric fields, thereby inhibiting the electrical tree growth. Another important aspect of enhancing XLPE's dielectric performance is the inclusion of antioxidants with phenolic groups. These antioxidants react with peroxyl radicals, mitigating their harmful effects. This review summarises the effects of nanoparticles, voltage stabilisers, antioxidants, and polymer amalgamation on dielectric performance of XLPE as an insulation material. The major challenges in dielectric insulation such as breakdown voltage strength, electrical tree growth, structural defect, space charge accumulation, and thermal aging are addressed.

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This study proposed wavelet-based approaches to characterise random vibration road excitations for durability prediction of coil springs. Conventional strain-life approaches require long computational time, while the accuracy of the vibration fatigue methods is unsatisfactory. It is therefore a necessity to establish an accurate fatigue life prediction model based on vibrational features. Wavelet-based methods were applied to determine the low-frequency energy and multifractality of road excitations. Strain-life models were applied for fatigue life evaluation from strain histories. ANFIS modelling was subsequently adopted to associate the vibration features with the fatigue life of coil springs. Results showed that the proposed wavelet-based methods were effective to determine the signal energy and multifractality of vibration signals. The established vibration-based models showed good fatigue life conservativity with a data survivability of more than 90%. The highest Pearson coefficient of 0.955 associated with the lowest RMSE of 0.660 was obtained by the Morrow-based model. It is suggested that the low-frequency energy and multifractality of the vibration signals can be used as fatigue-related features in life predictions of coil springs under random loading. Finally, the proposed model is an acceptable fatigue life prediction method based on vibration features, and it can reduce the dependency on strain data measurement.

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Poly(3,4-ethylenedioxythiophene)polystyrene sulfonate (PEDOT:PSS) is often used as a hole injection and extractor for various organic electronic devices. This study investigated whether it is possible to n-dope PEDOT:PSS with barium acetylacetonate (Ba(acac)2) to change its work function so that to be more suitable for electron injection and extraction. Molecular dynamics simulations suggested that barium cations can interact with the aromatic rings of PEDOT and the negatively charged sulfonate in PSS. At high doping concentration, we found that PEDOT became dedoped and precipitated resulting in a clear solution after filtration. The absence of the absorption peak of PEDOT at 263 nm indicates the removal of PEDOT after filtration. The shift in O 1s to a lower binding energy as seen in X-ray photoelectron spectroscopy suggested that the polystyrene sulfonic acids are being ionized to form barium polystyrene sulfonate (Ba-PSS). By spin-coating the solution on top of indium tin oxide, the work function can be adjusted to as low as 3.6 eV. The ability of such a mixture to inject and extract electrons is demonstrated using 2,7-bis(diphenylphosphoryl)-9,9'-spirobifluorene as an electron transporting layer. We attributed the lowering of the work function as the result of the formation of an interfacial dipole as large as 1.37 eV at the ITO/Ba-PSS interface.

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Calcium contents of demineralised human cortical bone determined by titrimetric assay and atomic absorption spectrophotometry technique were verified by comparing to neutron activation analysis which has high recovery of more than 90%. Conversion factors determined from the comparison is necessary to correct the calcium content for each technique. Femurs from cadaveric donors were cut into cortical rings and demineralised in 0.5 M hydrochloric acid for varying immersion times. Initial calcium content in the cortical bone measured by titration was 4.57%, only 21% of the measurement by neutron activation analysis; while measured by atomic absorption spectrophotometer was 13.4%, only 61% of neutron activation analysis. By comparing more readings with the measurements by neutron activation analysis with 93% recovery, a conversion factor of 4.83 was verified and applied for the readings by titration and 1.45 for atomic absorption spectrophotometer in calculating the correct calcium contents. The residual calcium content started to reduce after the cortical bone was demineralised in hydrochloric acid for 8 h and reduced to 13% after 24 h. Using the linear relationship, the residual calcium content could be reduced to less than 8% after immersion in hydrochloric acid for 40 h. Atomic absorption spectrophotometry technique is the method of choice for calcium content determination as it is more reliable compared to titrimetric assay.

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Objective: Native fistula creation for hemodialysis in patients who have exhausted all their superficial veins presents a challenge to vascular practice. We review our experience in transposed basilic vein fistula (BVT) creation and its usage for hemodialysis. Materials and Methods: We analyzed the hospital operative registry from January 2009 till June 2012 to identify the total number of BVT created in our center. Medical records of all patients were traced, and patients were interviewed using a standard proforma. In our center, BVT is performed as a two-stage procedure. All patients were routinely assessed with duplex scan preoperatively and postoperatively. Results: Two hundred thirty-nine patients were recruited in the study. Of these patients, 50.6% were male and 49.4% were female. Mean age was 53.4 years. Of these patients, 81.2% had history of other previous fistula creation. Risk factors profile includes diabetes mellitus in 59.8%, hypertension in 86.2%, and smoking in 13.0%. Of these patients, 84.5% had no operative complication. Commonest complication was wound infection, 6.3%, followed by hemorrhage or hemotoma required surgical intervention, 5.9%, and pseudoaneurysm, 1.3%. Primary and secondary patencies were at 84.2% and 86.1% at 1 year and 67.7% and 70.5% at 3 years, respectively. Conclusion: BVT is a credible option for challenging patients with absence of superficial veins for native fistula creation with good patency and low operative complication rate. Preoperative ultrasound assessment improves patient selection and outcome of BVT.

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Approximately 1.6 million new cases of lung cancer are diagnosed annually (Jemal et al. CA: A Cancer Journal for Clinicians, 61, 69-90, 2011) and it remains the leading cause of cancer-related mortality worldwide. Despite decades of bench and clinical research to attempt to improve outcome for locally advanced, good performance status patients, the 5-year survival remains less than 15 % (Molina et al. 2008). Immune checkpoint inhibitor (ICH) therapies have shown a significant promise in preclinical and clinical trails to date in the treatment of non-small cell lung cancer (NSCLC). The idea of combining these systemic immune therapies with local ablative techniques is one that is gaining momentum. Electrochemotherapy (ECT) is a unique atraumatic local therapy that has had very promising objective response rates and a number of advantages including but not limited to its immunostimulatory effects. ECT in combination with ICHs offers a novel approach for dealing with this difficult disease process.

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deep venous thrombosis (dVT) in lower limbs caused by abdominal aortic aneurysm (AAA) is rare. A combination of anatomical obstruction with surrounding inflammatory tissue and reduced blood flow in venous limb were probably the main reasons for the occurrence of the dVT. we report a case of infra-renal AAA presented as lower limb dVT and symptomatic pulmonary embolism.

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Giant lipomatous lesions of the thigh swelling with extension into retroperitoneum are rare. Lesions can be malignant or benign and can have similar clinical presentation. Treatments options differ and their prognosis varies with histology. We present two cases of liposarcoma and lipoma with the same clinical presentations that underwent surgical resection.

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INTRODUCTION: Peripheral arterial disease(PAD) and abdominal aortic aneurysm(AAA) are two important underdiagnosed vascular pathologies. As they share common risk factors with coronary arterial disease, we conducted a study to look at their prevalence among patients with acute coronary syndrome(ACS). MATERIALS AND METHODS: Patients with ACS admitted to Queen Elizabeth Hospital, Malaysia, from February 2009 till August 2009 were screened prospectively for PVD and AAA. Patients' data and clinical findings were gathered and analyzed. Measurements of ankle brachial index (ABI) and abdominal aortic diameter were performed by a single assessor. PAD was defined as ABI ≤ 0.9 or diabetic patients with signs and symptoms of PAD and absence of pedal pulses. AAA was defined as abdominal aortic diameter ≥ 3cm. RESULTS: 102 patients were recruited with mean age of 59.5 years old. Male: female ratio was 6:1. 40.2% of patients had NSTEMI; 45.1%, STEMI and 14.7%, unstable angina. Risk factors profile is as follows: hypertension- 68.6%, smoking- 56.9%, hypercholesterolemia- 52.9%, diabetes mellitus- 35.3% and history of stroke- 5.9%. Median ABI was 1.1 with lowest reading of 0.4. Mean abdominal aortic size was 2.0cm with largest diameter of 3.3cm. PAD was present in 24.5% of patients and AAA in 2.0%. 68.0% of patients with PAD were asymptomatic. Smoking and age more than 60 years were independent predictors for PAD among ACS patients. CONCLUSIONS: PAD is strongly correlated with CAD with old age and smoker as independent predictors. However, association between AAA and ACS could not be established.

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This is our initial report on the first 4 cases of infra-renal abdominal aortic aneurysms undergoing Endovascular Aneurysm Repair (EVAR) with local anaesthesia, controlled sedation and monitoring by an anaesthetist. All 4 patients were males with a mean age of 66.7 years. Only one (1) required ICU stay of 2 days for cardiac monitoring due to bradycardia and transient hypotension post procedure. No mortality or major post operative morbidity was recorded and the mean hospital stay post procedure was 3.5 days (range 2-5 days).

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The ability of palm oil (PO) to crystallize as beta prime polymorph has made it an attractive option for the production of margarine fat (MF). Palm stearin (PS) expresses similar crystallization behavior and is considered one of the best substitutes of hydrogenated oils due to its capability to impart the required level of plasticity and body to the finished product. Normally, PS is blended with PO to reduce the melting point at body temperature (37 °C). Lipid phase, formulated by PO and PS in different ratios were subjected to an emulsification process and the following analyses were done: triacylglycerols, solid fat content (SFC), and thermal behavior. In addition, the microstructure properties, including size and number of crystals, were determined for experimental MFs (EMFs) and commercial MFs (CMFs). Results showed that blending and emulsification at PS levels over 40 wt% significantly changed the physicochemical and microstructure properties of EMF as compared to CMF, resulting in a desirable dipalmitoyl-oleoyl-glycerol content of less than 36.1%. SFC at 37 °C, crystal size, crystal number, crystallization, and melting enthalpies (ΔH) were 15%, 5.37 µm, 1425 crystal/µm(2), 17.25 J/g, and 57.69J/g, respectively. All data reported indicate that the formation of granular crystals in MFs was dominated by high-melting triacylglycerol namely dipalmitoyl-oleoyl-glycerol, while the small dose of monoacylglycerol that is used as emulsifier slowed crystallization rate. Practical Application: Most of the past studies were focused on thermal behavior of edible oils and some blends of oils and fats. The crystallization of oils and fats are well documented but there is scarce information concerning some mechanism related to crystallization and emulsification. Therefore, this study will help to gather information on the behavior of emulsifier on crystallization regime; also the dominating TAG responsible for primary granular crystal formations, as well as to determine the best level of stearin to impart the required microstructure properties and body to the finished products.

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Children who would benefit from a haematopoietic stem cell transplantation often lacked a compatible sibling donor. Unrelated cord blood transplantation was offered as an alternative donor source for patients with a variety of malignant and non-malignant diseases who had no further treatment options. Cord blood units were sourced from various international cord blood registries. The median nucleated and CD34+ cell doses were 8.7 x 10(7)/kg and 2.6 x 10(5)/kg respectively. In spite of adequate cell doses, a high rate of non-engraftment of 32% was observed. Acute graft-versus-host disease (GVHD) occurred in 14 out of the 15 patients who engrafted with 53% being grade III to IV GVHD. The five year disease free survival was 40.7% with infection and GVHD being the commonest causes of death. The five year disease free survival was 20.5% and 60.7% for malignant and non-malignant diseases respectively.

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This finite element analysis is aimed at comparing relative stiffness of three different posterior instrumentation constructs: the Hospital Universiti Kebangsaan Malaysia Spinal Instrumentation System (HUKM-SIS), the Cotrell-Dubousset Instrumentation (CDI) and Harrington Instrumentation System (HIS), used in the treatment of adolescent idiopathic scoliosis (AIS). The constructs were tested under various loads using MSC Patran 2001 r2a. Under increasing flexion loads, there was a linearly corresponding increase in deflection magnitudes for all constructs on the load-deflection curve. The CDI was the stiffest construct under axial, forward flexion and extension loads, followed by the HUKM-SIS and HIS. Under lateral bending loads, the HUKM-SIS construct was the stiffest followed by CDI and HIS. The HUKM-SIS construct was stiffer than HIS under torsional loads. We conclude that multiple pedicle screws increase the stiffness of posterior instrumentation constructs under all loads and inter-segmental spinous processes wiring increase the stiffness against lateral bending.

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Various blend ratios of high-density polyethylene (HDPE) and ultra high molecular weight polyethylene (UHMWPE) were prepared with the objective of determining their suitability as biomaterials. In the unfilled state, a blend of 50/50 (HDPE/UHMWPE) ratio by weight was found to yield optimum properties in terms of processability and mechanical properties. Hydroxyapatite (HA) was compounded with the optimum blend ratio. The effects of HA loading, varied from 0 to 50wt% for both filled and unfilled blends were tested for mechanical properties. It was found that the inclusion of HA in the blend led to a remarkable improvement of mechanical properties compared to the unfilled blend. In order to improve the bonding between the polymer blend and the filler, the HA used was chemically treated with a coupling agent known as 3-(trimethoxysiyl) propyl methacrylate and the treated HA was mixed into the blend. The effect of mixing the blend with silane-treated HA also led to an overall improvement of mechanical properties.

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Two 4-year-old monozygotic Chinese, female twins developed concordant childhood acute lymphoblastic leukemia (ALL) within an interval of about 2 weeks. Based on morphology and cytochemistry findings of the bone marrow blast cells, a diagnosis of ALL, L1 was made. Immunophenotyping showed the blast cells of both twins expressed similar antigens, i.e. HLA-DR, CD10, CD13, CD19, CD22 and CD34. Identical blood group, same HLA (human leucocyte antigen) genotype, sex and similar appearance suggest that the twins are monozygotic. Since the bone marrow leukemic cells of both twins were identical in morphology and expressed the same antigens with almost similar percentages of positivity, it is likely that the blast cells were derived from the same single clone. Based on the single clone hypothesis, the leukemogenic event must have arisen in utero in one twin and the cells from the abnormal clone then spread to the other twin via shared placental anastomoses.

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The effect on macular function of the wavelength of laser light used to treat proliferative diabetic retinopathy was studied. Thirty-six eyes of 25 patients received panretinal photo-coagulation according to a standardised protocol and before and at intervals after the treatment were tested by a battery of macular function tests. Each eye was randomly assigned to treatment with blue-green, yellow, or orange laser. The tests included best corrected visual acuity, colour vision, contrast sensitivity, macular threshold, and central visual fields. There were no significant differences in the results of these tests between the three treatment groups, though there was wide scattering of baseline values within each group. Laser wavelength has not been shown to be an important determinant of central visual function following panretinal photo-coagulation in patients with proliferative diabetic retinopathy within the wavelengths tested.

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Palmitoylcarnitine was oxidised by pea mitochondria.L-carnitine was an essential addition for the oxidation of palmitate or palmitoylCoA. When palmitate was sole substrate, ATP and Mg(2+) were also essential additives for maximum oxidation. Additions of CoA inhibited the oxidation of palmitate. It was shown that CoA was acting as a competitive inhibitor of the carnitine-stimulated O2 uptake. It is suggested that palmitoylacarnitine and carnitine passed through the mitochondrial barrier with ease but palmitoylCoA and CoA did not. The presence of carnitine long-chain acyl (palmitoyl)transferase (EC 2.3.1.21) in pea-cotyledon mitochondria was shown. This enzyme may play a role in the transport of long-chain acyl groups through membrane barriers.

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Carnitine acetyltransferase was shown to be present in pea-cotyledon mitochondria. Acetyl-carnitine may well be exported, without excessive energy loss, from mitochondrial matrix sites to extra-mitochondrial sites.

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Etio-chloroplasts of barley, purified on sucrose density gradients were shown to possess carnitine long-chain acyltransferase (carnitine palmitoyltransferase, EC 2.3.1.21) activity and carnitine short-chain acyltransferase (carnitine acetyltransferase EC 2.3.1.7) activity. These enzymes may play a role in the transport of acyl groups as acylcarnitines through the membrane barrier of barley etio-chloroplasts and also 'or alternatively' may spare CoA by transferring short- and long-chain acyl groups from short-and long-chain acyl CoA to carnitine.