Remarkable thermal conductivity enhancement in Ag-decorated graphene nanocomposites based nanofluid by laser liquid solid interaction in ethylene glycol.

We report on the synthesis and enhanced thermal conductivity of stable Ag-decorated 2-D graphene nanocomposite in ethylene glycol based nanofluid by laser liquid solid interaction. A surfactant free nanofluid of Ag nanoparticles anchored onto the 2-D graphene sheets were synthesized using a two-step laser liquid solid interaction approach. In order to understand a pulsed Nd:YAG laser at the fundamental frequency (λ = 1,064 nm) to ablate Ag and graphite composite target submerged in ethylene glycol (EG) to form AgNPs decorated 2-D GNs-EG based nanofluid. From a heat transfer point of view, it was observed that the thermal conductivity of this stable Ag-graphene/EG is significantly enhanced by a factor of about 32.3%; this is highest reported value for a graphene based nanofluid.

Data Centre Profile: The Provincial Health Data Centre of the Western Cape Province, South Africa.

INTRODUCTION: The Western Cape Provincial Health Data Centre (PHDC) consolidates person-level clinical data across government services, leveraging sustained investments in patient registration systems, a unique identifier, and maturation of administrative and clinical digital health systems. OBJECTIVES: The PHDC supports clinical care directly through tools for clinicians which integrate patient data or identify patients in need of interventions, and indirectly through supporting operational and epidemiological analyses. METHODS: The PHDC is housed entirely within government. Data are processed from a range of source systems, usually daily, through distinct harmonisation and curation, beneficiation, and reporting processes. Linkage is predominantly through the unique identifier which doubles as a pervasive folder number, augmented by other identifiers. Further data processing includes triangulation of multiple data sources for enumerating health conditions, with assignment of certainty levels for each enumeration. Outputs include patient-specific email alerts, a web-based consolidated patient clinical viewing platform, filterable line-listings of patients with specific conditions and associated characteristics and outcomes, management reports and dashboards, and data releases in response to operational and research data requests. Strict architectural, administrative and governance processes ensure privacy protection. RESULTS: In the past decade 8 million unique people are recorded as having sought healthcare in the provincial public sector health services, with current utilisation at 15 million attendances or admissions a year. Cross-sectional enumeration of health conditions includes over 430 000 people with HIV, 500 000 with hypertension, 235 000 with diabetes. Annually 110 000 pregnancies and 54 000 patients with tuberculosis are enumerated. Over 50 data requests are processed each year for internal and external requesters in accordance with data request and release governance processes. CONCLUSIONS: The single consolidated environment for person-level health data in the Western Cape has created new opportunities for supporting patient care, while improving the governance around access to and release of sensitive patient data.

The morphometry and morphology of the foramen magnum in age and sex determination within the south african black population utilizing computer tomography (CT) scans / Morfometría y morfología del foramen magnum en la determinación de edad y sexo dentro de la población negra sudafricana mediante tomografía computarizada (TC)

SUMMARY: The morphology and morphometry of the foramen magnum aid forensic studies in identifying unknown individuals according to age and sex. Moreover, these parameters of the foramen magnum have clinical relevance to surgeons in the transcondylar approach. This study aimed to analyze the morphometry and morphology in relation to the age and sex of individuals within the South African Black population, utilizing computerized tomography images. The use of computerized tomography images allowed for accurate morphometric diameters using the SLICER 3-D software version 4.7.0. Radiological images also provide a patient's clinical history. Thus, the process of exclusion in respect to patients with pathological conditions of the skull is achieved. The sample studied included 150 computerized tomography images (93 males and 57 females) arranged according to age cohorts (children aged 1-12 years, adolescents aged 13-17 years and adults aged 18-25 years). The morphometric parameters viz. antero-posterior diameter, transverse diameter and area of the foramen magnum was analyzed in relation to age and sex. The morphological variations of the foramen magnum was simultaneously observed between males and females and within the age groups. The objective of this study were to improve data on the morphological and morphometric parameters of the foramen magnum in the South African Black population. This study also attempted to associate the morphological and morphometric parameters of the foramen magnum with age and sex determination.

RESUMEN: La morfología y morfometría del foramen magnum ayuda a los estudios forenses en la identificación de individuos desconocidos según la edad y el sexo. Además, parámetros del foramen magnum tienen relevancia clínica para los cirujanos en el abordaje transcondilar. Este estudio tuvo como objetivo analizar la morfometría y la morfología del foramen magnum, en relación con la edad y el sexo, dentro de la población negra sudafricana, utilizando imágenes de tomografía computarizada. El uso de imágenes de tomografía computarizada permitió definir diámetros morfométricos precisos utilizando el software SLICER 3-D versión 4.7.0. Las imágenes radiológicas también proporcionan antecedentes de la historia clínica de un paciente. De este modo, se logra el proceso de exclusión con respecto a los pacientes con afecciones patológicas del cráneo. La muestra estudiada incluyó 150 imágenes de tomografía computarizada (93 hombres y 57 mujeres) organizadas según cohortes de edad (niños de 1 a 12 años, adolescentes de 13 a 17 años y adultos de 18 a 25 años). Los parámetros morfométricos que se consideraron fueron: diámetro antero-posterior, diámetro transversal y área del foramen magnum. Las variaciones morfológicas del foramen magnum se observaron simultáneamente entre hombres y mujeres y dentro de los grupos de edad. El objetivo de este estudio fue mejorar los datos sobre los parámetros morfológicos y morfométricos del foramen magnum en la población negra sudafricana. Este estudio también intentó asociar los parámetros morfológicos y morfométricos del foramen magnum con la determinación de la edad y el sexo.

Solid-State Synthesis of POPD@AgNPs Nanocomposites for Electrochemical Sensors.

In the present work, Poly(o-phenylenediamine) (POPD) stabilized silver nanoparticles (POPD@AgNPs) nanocomposites was synthesized by solid state oxidative polymerization method using o-phenylenediamine dihydrochloride (oPD-HCl) as monomer and silver nitrate (AgNO3) used as metal precursor as well as oxidizing agent no other external oxidizing agent was used. POPD@AgNPs nanocomposites were characterized by various instrumental techniques to confirm their size, shape and its composition. The electrocatalytic activity of POPD and POPD@AgNPs modified electrode was investigated over the oxidation of hydrazine (N2H4) and reduction of hydrogen peroxide (H2O2) using Cyclic Voltammetry (CV), Differential Pulse Voltammetry (DPV) and Chronoamperometry techniques. POPD and POPD@AgNPs were characterized using HR-TEM, FE-SEM, XRD, UV-Visible, FT-IR, Micro Raman spectroscopy and those results were confirmed their chemical purity, particle size, shape and its elemental compositions. Moreover, the DPV and chronoamperometry reveals that POPD@AgNPs is a good sensor for the electrochemical gas detection of N2H4 and H2O2 because it has good stability, easy-operation, excellent reproducibility, high sensitivity and good limit of detection when compared to with pure POPD. This system shows good stability, excellent sensitivity, response and the detection limit was obtained for the detection of N2H4 and H2O2 in trace level gases, which was lower than some of the modified electrodes.

The impact of anticancer activity upon Beta vulgaris extract mediated biosynthesized silver nanoparticles (ag-NPs) against human breast (MCF-7), lung (A549) and pharynx (Hep-2) cancer cell lines.

The present study tried for a phyto-synthetic method of producing silver nanoparticles (Ag-NPs) with size controlled as and eco-friendly route that can lead to their advanced production with decorative tranquil morphology. By inducing temperature fluctuation of the reaction mixture from 25 to 80°C the plasmon resonance band raised slowly which had an ultimate effect on size and shape of Ag-NPs as shown by UV-visible spectroscopy and TEM results. The biosynthesized nanoparticles showed good cytotoxic impact against MCF-7, A549 and Hep2 cells compared to normal cell lines. Compared to control plates, the percentage of cell growth inhibition was found to be high with as concentrations of Ag-NPs becomes more as determined by MTT assay. The AO/EtBr staining observations demonstrated that the mechanism of cell death induced by Ag-NPs was due to apoptosis in cancer cells. These present results propose that the silver nanoparticles (Ag-NPs) may be utilized as anticancer agents for the treatment of various cancer types. However, there is a need for study of in vivo examination of these nanoparticles to find their role and mechanism inside human body. Further, studies we plan to do biomarker fabrication from the green synthesized plant extract nanoparticles like silver, gold and copper nanoparticles with optimized shape and sizes and their enhancement of these noble nanoparticles.

Charge Carrier Transport Mechanism Based on Stable Low Voltage Organic Bistable Memory Device.

A solution processed two terminal organic bistable memory device was fabricated utilizing films of polymethyl methacrylate PMMA/ZnO/PMMA on top of ITO coated glass. Electrical characterization of the device structure showed that the two terminal device exhibited favorable switching characteristics with an ON/OFF ratio greater than 1 x 10(4) when the voltage was swept between - 2 V and +3 V. The device maintained its state after removal of the bias voltage. The device did not show degradation after a 1-h retention test at 120 degrees C. The memory functionality was consistent even after fifty cycles of operation. The charge transport switching mechanism is discussed on the basis of carrier transport mechanism and our analysis of the data shows that the charge carrier trans- port mechanism of the device during the writing process can be explained by thermionic emission (TE) and space-charge-limited-current (SCLC) mechanism models while erasing process could be explained by the FN tunneling mechanism. This demonstration provides a class of memory devices with the potential for low-cost, low-power consumption applications, such as a digital memory cell.

Zinc oxide epitaxial thin film deposited over carbon on various substrate by pulsed laser deposition technique.

Zinc Oxide (ZnO) is a promising candidate material for optical and electronic devices due to its direct wide band gap (3.37 eV) and high exciton binding energy (60 meV). For applications in various fields such as light emitting diode (LED) and laser diodes, growth of p-type ZnO is a prerequisite. ZnO is an intrinsically n-type semiconductor. In this paper we report on the synthesis of Zinc Oxide-Carbon (ZnO:C) thin films using pulsed laser deposition technique (PLD). The deposition parameters were optimized to obtain high quality epitaxial ZnO films over a carbon layer. The structural and optical properties were studied by glazing index X-ray diffraction (GIXRD), photoluminescence (PL), optical absorption (OA), and Raman spectroscopy. Rutherford backscattering spectroscopy (RBS), scanning electron microscopy with energy dispersive spectroscopy (SEMEDS) and atomic force microscopy (AFM) were employed to determine the composition and surface morphology of these thin films. The GIXRD pattern of the synthesized films exhibited hexagonal wurtzite crystal structure with a preferred (002) orientation. PL spectroscopy results showed that the emission intensity was maximum at -380 nm at a deposition temperature of 573 K. In the Raman spectra, the E2 phonon frequency around at 438 cm(-1) is a characteristic peak of the wurtzite lattice and could be seen in all samples. Furthermore, the optical direct band gap of ZnO films was found to be in the visible region. The growth of the epitaxial layer is discussed in the light of carbon atoms from the buffer layer. Our work demonstrates that the carbon is a novel dopant in the group of doped ZnO semiconductor materials. The introduction of carbon impurities enhanced the visible emission of red-green luminescence. It is concluded that the carbon impurities promote the zinc related native defect in ZnO.

Human papillomavirus (HPV)-type distribution in relation to oral contraceptive use in women with cervical intraepithelial neoplasia, Durban, South Africa.

OBJECTIVE: To determine HPV-type distribution among women with cervical dysplasia in relation to oral contraceptive usage. METHODS: Prospective cross-sectional study of four groups of patients according to oral contraceptive usage: non-users, users of less than five years duration, users of between five years and ten years, and users of more than ten years duration. Swabs of the cervix were analysed for HPV DNA using the polymerase chain reaction method. RESULTS: A total of 124 women were recruited for the study. There were 75 patients who were HIV-infected (seroprevalence 61%). There were 102 patients who were HPV positive (82%), of which 79 patients had high-risk HPV DNA (78%). In terms of the four oral contraceptive groups, high-risk HPV DNA was detected in 70% (n = 21), 79% (n = 22), 90% (n = 21) and 71% (n = 15) of patient, respectively. The odds of having HPV DNA was six times higher for the combination of contraceptive users of less than five years duration/non-users (OR 5.9, 95% CI: 1.87-18.77). There was no change when adjustment was made for age (OR 6.1, 95% CI: 1.9-19.4). HPV DNA type 16 and/or 18 was present in a total of 21 patients (49%) (non-contraceptive users and users < 5 years duration) versus 15 patients (42%) (oral contraceptive users of more than 5 years duration) (p = 0.524). HPV type 16 was the commonest HPV type detected (20.2%) and HPV type 58 was the next commonest hihg-risk HPV type (16.1%). HPV types 58 and 33 were detected in a much greater percentage of our population and HPV 16 in a much smaller percentage of our population compared with a non-South African population. CONCLUSION: The findings of this study demonstrate an interesting distribution of HPV types in a South African population.

Primary non-Hodgkins lymphoma of the ovary in the background of human immunodeficiency virus (HIV): a bold and curative approach to treatment.

Non-Hodgkins lymphoma of the ovary is a rare disease and there is only one previously documented case arising in a patient with human immunodeficiency virus (HIV). In this report, the authors discuss the management of a case of non-Hodgkins Lymphoma of the ovary occurring in a patient with HIV and demonstrate that treatment regimens may be successfully implemented in this immunocompromised population without an increase in adverse effects.

Trends of histopathology of cervical cancer among women in Durban, South Africa.

INTRODUCTION: Cervical squamous cell carcinoma has traditionally been the commonest histological type of cervical cancer. Adenocarcinoma has recently been reported to occur with increasing frequency. METHODS: This retrospective study was conducted on 2,930 patients with cervical cancer over an eight-year period (1995-2002) recruited from the combined Gynaecology Oncology Clinic at King Edward VIII Hospital (KEH), Pathology Laboratories at KEH, and from the private sector. RESULTS: In the public sector squamous cell carcinoma was found to be the commonest type of cervical cancer irrespective of ethnicity and age. It was found to occur in over 80% of patients and remained fairly static over the time period. In the private sector, a slightly higher proportion (38.8%) of women had adenocarcinoma, however since the total number of patients were small (85) there was no statistically significant increase in adenocarcinoma relative to squamous cell carcinoma. There was no correlation between the documented risk factors i.e., smoking, contraception and human papillomavirus and histological type of cervical cancer. Similarly, there was no statistically significant relationship between ethnicity, differentiation, type of cervical cancer and age of the patient in both sectors. CONCLUSION: This study has not revealed an increasing incidence in cervical adenocarcinoma in the public setting. However, in the private sector, a significant proportion of black women (38.8%) had adenocarcinoma. All Asian women had adenocarcinoma while 25% of the white women had adenocarcinoma. Although the total number of patients in this group are small (85), these results cannot be ignored.

Placental site trophoblastic tumor with antecedent molar pregnancy in association with human immunodeficiency virus infection.

The occurrence of placental site trophoblastic tumor (PSTT) is rare. PSTT following molar pregnancy is uncommon. The report describes the presentation of PSTT following molar pregnancy in the background of human immunodeficiency virus infection.

Round worm infestation as a cause of small bowel anastomotic breakdown following urinary diversion for cervical cancer.

BACKGROUND: Vesicovaginal fistulae are well-recognized complications of radiotherapy for the treatment of cervical cancer. These patients often require some form of urinary diversion. Small bowel is often utilized for these purposes. CASE: A patient with stage IIB cervical cancer presented with a vesicovaginal fistula 6 years post-radiotherapy. An ileal conduit was performed. On day 9 post-surgery breakdown of the small bowel anastomosis was suspected. At laparotomy small bowel anastomotic breakdown was confirmed with round worms at the anastomotic site. CONCLUSION: Perforation of small bowel by round worm has been previously described in a patient with Meckel' s diverticulum. This report describes an unusual cause of small bowel anastomotic breakdown following urinary diversion.

Radical hysterectomy for cervical cancer amongst women infected with the human immunodeficiency virus.

Invasive cervical cancer and human immunodeficiency virus (HIV) infection are an epidemic in South Africa. Most HIV-infected patients with cervical cancer present with late-stage disease. Whilst the literature describes the outcome of such women with preneoplastic cervical lesions, the management of early-stage invasive cervical cancer and HIV is lacking. We present our experience with such patients.

The effects of a polyacrylamide-derived water treatment residue on the hydraulic conductivity, water retention and evaporation of four contrasting South African soils and implications for land disposal.

Water treatment residue (WTR), a by-product from the production of potable water, was traditionally disposed of to landfill but there is growing interest in applying this waste to land as an alternative disposal option. Because WTR consists mainly of flocculated fine silt and clay, there is concern that should the residue decompose back to its original constituents, there is an adverse risk for soil water storage and transmission properties of soil. In a laboratory study, four different soil types were amended with a polyacrylamide WTR at rates ranging from 0 to 1280 Mg ha(-1). The treatments were evaluated for changes in water retention, hydraulic conductivity and evaporation. The results showed that WTR decreased bulk density and evaporation and actually increased hydraulic conductivity and water retention, mainly because of the sustained performance of the polymer in binding the silt and clay into gravel-sized aggregates. Such changes were, however, only significant at the 1280 Mg ha(-1) application rate. Therefore, very large amounts of WTR would have to be applied in order to markedly change these inherent physical properties of the soils. In view of this finding, the land treatment of WTR appears possible.

Reduction in prevalence of invasive cervical cancer in KwaZulu-Natal, South Africa: impact of the human immunodeficiency virus epidemic.

The bulk of the human immunodeficiency virus (HIV) pandemic continues to ravage the developing world, especially sub-Saharan countries. The HIV seroprevalence among women with invasive cervical cancer varies in different parts of the world. A comparison of women with cervical cancer was undertaken for epidemiologic data in the province of KwaZulu-Natal, South Africa, which has the highest HIV prevalence. The two time periods of study were 1999 and 2003. The aim was to determine the trends of prevalence of invasive cervical cancer and HIV infection among such women. While the background prevalence of HIV infection among women with invasive cervical cancer in our setting has remained constant over the two time periods (21% and 21.8%), there has been a significant reduction in the number of women presenting with invasive cervical cancer to our center (672 to 271) over the two time periods, with no changes in other variables. On the contrary, the prevalence of HIV infection among antenatal attendees had risen from 32.5% to 38.5% in the 1999 and 2003 periods, respectively. Reasons for this dramatic trend are presented together with other epidemiologic data.

Ewing's sarcoma of the vulva--a case report.

Extraosseous Ewing's sarcoma of the vulva is extremely rare with only three such cases described. A 26-year-old woman presented with Ewing's sarcoma of the vulva. She received chemotherapy to shrink the lesion. However, the response was suboptimal and she subsequently received radiotherapy. Although resection was planned, she developed chest metastases within a short period of time and subsequently died.

Frozen section: Its role in gynaecological oncology.

The use of frozen section has greatly impacted on the care of the gynaecological oncology patient. Frozen section allows intraoperative evaluation to distinguish benign from malignant tumors in order to tailor the extent of surgery necessary. Frozen section diagnosis in gynaecological oncology is sufficiently sensitive and specific for clinical use. Generally, the false negative rate is low and the false positive rate is negligible. Deferred diagnoses or incompatible frozen section diagnosis is usually due to technical limitations especially for the mucinous ovarian tumors. This review summarises the available literature on the accuracy, limitations and role of frozen section for individual gynaecological tumors.

Invasive cervical cancer and human immunodeficiency virus (HIV) infection in KwaZulu-Natal, South Africa.

The human immunodeficiency virus (HIV) can be expected to influence the course of disease and response to treatment of invasive carcinoma of the cervix. The extent and nature of this influence, however remains largely unknown. We therefore undertook a retrospective analysis of patients with carcinoma of the cervix at a tertiary referral centre in an African setting where HIV prevalence is high. There were 271 patients seen during a period of 1 year. Of these, 45 of the 206 tested were HIV infected (21.8%). The corresponding HIV prevalence for antenatal attendees was 38.7% in the region. The HIV-infected patients had lower mean haemoglobin levels and body mass indices than the HIV-non-infected women and were on average 13 years younger (p < 0.001), but otherwise did not differ with respect to demographics or disease parameters. They were, however, less likely to complete planned treatment. CD4 counts were below 200 in only 6 (21%) of 29 women tested. HIV-infected women in the African setting present with carcinoma of the cervix at a younger age, but the same disease stage as HIV-non-infected women, and without evidence of advanced immunocompromise. Circumstantial evidence is put forward by the study to suggest a more rapid decline in health and earlier demise for HIV-infected women with carcinoma of the cervix.