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Aim: This is a cross-sectional study to determine the prevalence and risk factors for transmission of hepatitis B virus (HBV) infection in the Gezira state of central Sudan prior to the introduction of blood screening and vaccination against HBV. Materials and Methods: The study was carried out on the population of Um Zukra village in Gezira state of Central Sudan. The village was surveyed on five consecutive days in Dec 2000. Epidemiological characteristics were recorded and participants were interviewed for risk factors of viral hepatitis. Blood samples were then collected and tested for HBsAg and HBcAb. Results: A total of 404 subjects were screened with a mean age of 35 years; 54.9% were females, HBsAg and HBcAb were reactive in 6.9% and 47.5% of the studied population, respectively. Exposure to HBV increased with increasing age. The only significant risk factor for transmission of infection was a history of parenteral antischistosomal therapy. Conclusion: This study shows that prevalence of HBV infection is high in the studied population and it is hoped that introduction of blood screening and vaccination against HBV would decrease the carrier pool in the next few years.

Authigenic monazite nodules, increasingly recognized in Pre-Mesozoic mudrock successions, provide a means for dating diagenesis by exploiting trace uranium within the monazite structure. But, dating is difficult in practice because of zonation and abundant host rock inclusions. We report here a refined technique that has yielded a date of 419 [+ or -] 14 Ma 2[sigma] MSWD = 1.2 for a 17-point Pb-Pb regression age from a Telychian (Silurian: late Llandovery) mudrock from central Wales. SHRIMP analyses of monazite nodules from the same horizon are consistent with this, and additionally demonstrate concordance of the U-Pb and Th-Pb systems. These results open the door to providing robust dates for a phase of burial-related diagenesis which, in Wales, seems approximately coincident with, and perhaps was related to, hydrocarbon expulsion. Keywords: Palaeozoic, Welsh Basin, oil window, monazite.

The article offers information on various topics including the murder of Saudi journalist Jamal Khashoggi, the investigation on the death of Khashoggi, and the foreign relations of Saudi Arabia and Iran. Also mentioned are the social aspects of colonialism, the foreign relations of United Arab Emirates and Great Britain, and the Islamic Revolution in Iran.

Gas cluster ion beam sputtering has been used to study the self-organising behaviour of In metallic nanoparticles produced by preferential sputtering of phosphorus atoms in InP. Discrete plasmonic In nanoparticles are observed at the earliest stages of surface modification. The surfaces have been investigated in situ by reflection electron energy loss spectroscopy, Auger electron spectroscopy, and photoluminescence spectroscopy. By altering the excitation intensity, we observe alterations of the photoluminescence spectrum that are attributed to photoconductive-coupling between In nanoparticles. The devices presented are suitable for visible wavelength surface enhanced Raman spectroscopy and, potentially, offer a route to active all-optical switches. [ABSTRACT FROM AUTHOR]

ABSTRACT The Proterozoic belts that occur along the margins of the West Australian Craton, as well as those in intraplate settings, generally share similar geological histories that suggest a common plate-margin driver for orogeny. However, the thermal drivers for intraplate orogenesis are more poorly understood. The Mutherbukin Tectonic Event records a protracted period of Mesoproterozoic reworking of the Capricorn Orogen and offers significant insight into both the tectonic drivers and heat sources of long-lived intraplate orogens. Mineral assemblages and tectonic fabrics related to this event occur within a 50 km-wide fault-bound corridor in the central part of the Gascoyne Province in Western Australia. This zone preserves a crustal profile, with greenschist facies rocks in the north grading to upper amphibolite facies rocks in the south. The P- T- t evolution of 13 samples from 10 localities across the Mutherbukin Zone is investigated using phase equilibria modelling integrated with in situ U-Pb monazite and zircon geochronology. Garnet chemistry from selected samples is used to further refine the P-T history and shows that the dominant events recorded in this zone are prolonged D1 transpression between c. 1,320 and 1,270 Ma, followed by D2 transtension from c. 1,210 to 1,170 Ma. Peak metamorphic conditions in the mid-crust reached >650°C and 4.4-7 kbar at c. 1,210-1,200 Ma. Most samples record a single clockwise P-T evolution during this event, although some samples might have experienced multiple perturbations. The heat source for metamorphism was primarily conductive heating of radiogenic mid- and upper crust, derived from earlier crustal differentiation events. This crust was thickened during D1 transpression, although the thermal effects persisted longer than the deformation event. Peak metamorphism was terminated by D2 transtension at c. 1,210 Ma, with subsequent cooling driven by thinning of the radiogenic crust. The coincidence of a sedimentary basin acting as a thermal lid and a highly radiogenic mid-crustal batholith restricted to the Mutherbukin Zone accounts for reworking being confined to a discrete crustal corridor. Our results show that radiogenic regions in the shallow to mid crust can elevate the thermal gradient and localize deformation, causing the crust to be more responsive to far-field stresses. The Mutherbukin Tectonic Event in the Capricorn Orogen was synchronous with numerous Mesoproterozoic events around the West Australian Craton, suggesting that thick cratonic roots play an important role in propagating stresses generated at distant plate boundaries. [ABSTRACT FROM AUTHOR]

Asymmetry in vertical stiffness has been associated with increased injury incidence and impaired performance. The determinants of vertical stiffness asymmetry have not been previously investigated. Eighteen healthy men performed three unilateral drop jumps during which vertical stiffness and joint stiffness of the ankle and knee were calculated. Reactive strength index was also determined during the jumps using the ratio of flight time to ground contact time. 'Moderate' differences in vertical stiffness ( t17 = 5.49; P < 0.001), 'small' differences in center of mass displacement ( t17 = −2.19; P = 0.043), and 'trivial' differences in ankle stiffness ( t17 = 2.68; P = 0.016) were observed between stiff and compliant limbs. A model including ankle stiffness and reactive strength index symmetry angles explained 79% of the variance in vertical stiffness asymmetry ( R2 = 0.79; P < 0.001). None of the symmetry angles were correlated to jump height or reactive strength index. Results suggest that asymmetries in ankle stiffness may play an important role in modulating vertical stiffness asymmetry in recreationally trained men. [ABSTRACT FROM AUTHOR]

Visible wavelength surface-enhanced Raman spectroscopy (SERS) has been observed from bovine serum albumin (BSA) using In-InP nanopillars synthesised by Ar gas cluster ion beam sputtering of InP wafers. InP provides a high local refractive index for plasmonic In structures, which increases the wavelength of the In surface plasmon resonance. The Raman scattering signal was determined to be up to 285 times higher for BSA deposited onto In-InP nanopillars when compared with Si wafer substrates. These substrates demonstrate the label-free detection of biomolecules by visible wavelength SERS, without the use of noble metal particles. [ABSTRACT FROM AUTHOR]

The Monts de Cristal Complex of Gabon consists of several igneous bodies interpreted to be remnants of a tectonically dismembered, >100 km long and 1-3 km wide, ultramafic-mafic intrusion emplaced at 2765-2775 Ma. It is the most significant mafic-ultramafic layered complex yet identified on the Congo Craton. The complex consists largely of orthopyroxenite cumulates, with less abundant olivine-orthopyroxenite and norite, and rare harzburgite and dunite. Mineral compositions (Fool 84, Mg#Opx 85, Anplag 60-68, Cr/Fe chromite 1-1·45) and whole-rock data suggest that the parent magma was a low-Ti basalt containing approximately 10% MgO and 0·5% TiO2. Trace element and Rb-Sr and Sm-Nd isotope data indicate the presence of an enriched component, possibly derived from crustal contamination of a magma generated in the sub-lithospheric mantle. Most rocks show a highly unusual pattern of strong Pt enrichment (10-150 ppb) at low concentrations of Pd (1-15 ppb), Au (1-2 ppb), Cu (1-20 ppm), and S (<500 ppm), suggesting that unlike in most other PGE-rich intrusions globally, platinum in the Monts de Cristal Complex is not hosted in magmatic sulfides. Synchrotron X-ray fluorescence mapping has revealed the location of buried small Pt particles, most of which are associated with As. We propose that this constitutes some of the strongest evidence yet in support of magmatic crystallization of a Pt-As phase from S-undersaturated magma. [ABSTRACT FROM AUTHOR]

Current methods for modelling burnt area in Dynamic Global Vegetation Models involve complex fire spread calculations, which rely on many inputs, including fuel characteristics, wind speed and countless parameters. They are therefore susceptible to large uncertainties through error propagation. Using observed fractal distributions of fire scars in Brazilian Amazonia, we propose an alternative burnt area model for tropical forests, with fire counts as sole input and few parameters. Several parameterizations of two possible distributions are calibrated at multiple spatial resolutions using a satellite-derived burned area map, and compared. The tapered Pareto model most accurately simulates the total area burnt (only 3.5 km2 larger than the recorded 16 387 km²) and its spatial distribution. When tested pan-tropically using MODIS MCD14ML fire counts, the model accurately predicts temporal and spatial fire trends, but produces generally higher estimates than the GFED3.1 burnt area product, suggesting higher pan-tropical carbon emissions from fires than previously estimated. [ABSTRACT FROM AUTHOR]

The Kunene Complex of Namibia-Angola is one of the largest anorthosite massifs on Earth (up to 18,000 km²), consisting of several distinct anorthosite and leucotroctolite intrusions. The Namibian portion of the Kunene Complex measures ~80 x 50 km, ~4,000 km², and is dominated by the Zebra Mountain lobe, a ~16-km-thick dome-like mass of interlayered, relatively unaltered dark leucotroctolite with relatively altered, "white," anorthosite. Past studies and tine present work have found evidence for intrusion of two distinct phases of dark leucotroctolite into the white anorthosite, namely a relatively early, deformed, phase dated at 1363 ± 17 Ma (U-Pb in baddelyite), and a relatively later and undeformed phase whose absolute age remains unknown. The Kunene leucotroctolites are among the least evolved troctolites known from anorthosite complexes, with olivine containing 59 to 77 mol % forsterite and up to 1,700 ppm Ni, and plagioclase containing 56 to 69 mol % anorthosite. Our isotope data from the troctolites indicate a relatively small crustal component (δ18O ~5.3-7.3; δ34S, 0.5-1; and εNdτ, 0.9-1.8), whereas Nd and oxygen isotope data from the white anorthosites, published by other workers, showed a slightly larger crustal component (e.g., εNdτ as low as -3; δ18MOO up to 7.5%). In the periphery of the Kunene Complex are several, relatively small (<10 km²), mafic-ultramafic intrusions comprising peridotite, pyroxenite, gabbro, troctolite, and anorthosite. Some of these bodies are Ni-Cu-PGE mineralized, including the Ohamaremba troctolite, the Oncocua pyroxenite, and the Ombuku peridotite-gab-bronorite. The latter additionally contains a massive chromitite layer. A new U-Pb baddelyite age of 1220 ± 15 Ma for Ohamaremba indicates that the latter postdates the main Kunene Complex by -140 Ma. The relative enrichment in MgO, Cr, and Ni, and the O, Nd, and S isotope characteristics of Kunene magmatism suggest that the primary magmas were predominantly mantle-derived picrites or basalts. The massif-type anorthosites formed through ascent of feldspathic slurries followed by downward draining of residual liquid. Subsequent magma pulses formed troctolitic sills within the anorthosite plutons and mafic-ultramafic satellite intrusions in the periphery of the anorthosites. The recurring nature of Kunene mafic-ultramafic mag-matism results from several successive mantle upwellings. Partial mantle melts ascended through reactivated translithospheric lineaments along the southern margin of the Congo craton. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate whether different measures of inter-rater reliability will compute similar estimates with nominal data commonly encountered in communication studies. To make recommendations how reliability should be computed and described for communication coding instruments. METHODS: The raw data from an inter-rater study with three coders were analysed with; Cohen's [kappa], sensitivity and specificity measures, Fleiss's multirater [kappa](j), and an intraclass correlation coefficient (ICC). RESULTS: Minor differences were found between Cohen's [kappa] and an ICC model across paired data (largest margin=0.01). There were negligible differences between the multirater estimates e.g. [kappa](j) (0.52) and ICC (0.53). Sensitivity analyses were in general agreement with the multirater estimates. CONCLUSION: It is more practical to analyse nominal data with >2 raters with an appropriate model ICC for inter-rater studies, and little difference exists between Cohen's [kappa] or an ICC. PRACTICE IMPLICATION: Alternatives to Cohen's [kappa] are readily available, but researchers need to be aware of the different ICC definitions. An ICC model should be fully described in reports. Investigators are encouraged to supply confidence limits with inter-rater data, and to revisit guidance regarding the relative strengths of agreement of reliability coefficients. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate whether emotional intelligence (EI) developmental training workshops can lead to increases with the Bar-On Emotional Quotient (EQ-i) total scores. METHODS: A pilot study with a quasi-randomised controlled design was employed with self-report assessments conducted at baseline and post-intervention following a 7-month training programme. Medical students based at a UK-based medical school participated in the study, and 36 volunteer students were recruited to the control group with 50 students randomly assigned to receive the intervention. A total of 34 (68%) students in the intervention group attended the first intervention training workshop, 17 (34%) attended the majority of the monthly development sessions and completed the post-intervention assessment. In the control group only one participant did not complete the follow-up assessment. RESULTS: The intervention group had significantly higher EQ-i change from baseline mean scores than the control group. The intervention group mean scores had increased across time, whilst the control group mean scores slightly decreased. CONCLUSION: The EI developmental training workshops had a positive effect on the medical students in the intervention group. PRACTICE IMPLICATIONS: Further research is warranted to determine whether EI can be a useful measure in medical training, and the concept and measurement of EI requires further development. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To identify methods available for sequential analysis of dyadic verbal clinical communication and to review their methodological and conceptual differences. METHODS: Critical review, based on literature describing sequential analyses of clinical and other relevant social interaction. RESULTS: Dominant approaches are based on analysis of communication according to its precise position in the series of utterances that constitute event-coded dialogue. For practical reasons, methods focus on very short-term processes, typically the influence of one party's speech on what the other says next. Studies of longer-term influences are rare. Some analyses have statistical limitations, particularly in disregarding heterogeneity between consultations, patients or practitioners. Additional techniques, including ones that can use information about timing and duration of speech from interval-coding are becoming available. CONCLUSION: There is a danger that constraints of commonly used methods shape research questions and divert researchers from potentially important communication processes including ones that operate over a longer-term than one or two speech turns. Given that no one method can model the complexity of clinical communication, multiple methods, both quantitative and qualitative, are necessary. PRACTICE IMPLICATIONS: Broadening the range of methods will allow the current emphasis on exploratory studies to be balanced by tests of hypotheses about clinically important communication processes. [ABSTRACT FROM AUTHOR]

This paper reports results of scanning ion probe studies of silicon implantation profiles in source and drain regions of AlGaN/GaN high-electron-mobility transistor (HEMT) heterostructures. It is shown that both the undoped channel length and the transition region between implanted and nonimplanted regions become wider with increasing depth in the structure. These results may explain the previously reported existence of resistance associated with the transition region between implanted and non-implanted semiconductor regions in AlGaN/GaN HEMT heterostructures with non-alloyed Si-implanted source and drain ohmic contact regions. [ABSTRACT FROM AUTHOR]

Healthcare professionals, nurses with and without disabilities, administrators and personnel directors were surveyed to explore hiring practices and attitudes towards working with nurses with disabilities employed in clinical settings. Specifically the purpose of the study was to gather and analyze data regarding the perceptions of two groups towards nurses with disabilities: 1) employers and 2) other nurses (with and without a disability). The study defined a nurse with a disability as an RN who has an activity limitation, specifically an altered activity capability which limits mobility, ambulation, strength, coordination, or equilibrium. Findings suggest that nurses are more likely to be willing to work with an RN with a disability if they had worked with one in the past. However, overall acceptance of RNs with disabilities was not broad. [ABSTRACT FROM AUTHOR]

In situ SHRIMP U–Pb geochronology of monazite and xenotime in pelitic schists from the central Gascoyne Complex, Western Australia, shows that greenschist to amphibolite facies metamorphism occurred between c. 1030 and c. 990 Ma. Monazite from an undeformed rare-element pegmatite from the same belt gives a 207Pb/206Pb age of c. 950 Ma, suggesting that peak metamorphism and deformation was followed by pegmatite intrusion and coeval granite magmatism. Metamorphism in the central Gascoyne Complex was previously interpreted as Barrovian, largely based on the identification of kyanite in peak metamorphic assemblages, and has been attributed to intense crustal shortening and substantial tectonic thickening during Palaeoproterozoic continent–continent collision. However, the stable Al2SiO5 polymorph has been identified in this study as andalusite rather than kyanite, and the prograde assemblages of staurolite–garnet–andalusite–biotite–muscovite–quartz indicate temperatures of 500–550 °C and pressures of 3–4 kbar. These data show that the Palaeoproterozoic Gascoyne Complex underwent an episode of Grenvillian-aged intracontinental reworking concentrated in a NW–SE striking corridor, during the Edmundian Orogeny. Until now, the Edmundian Orogeny was thought to have involved only reactivation of structures in the Gascoyne Complex, along with deformation and very low- to low-grade metamorphism of Mesoproterozoic cover rocks some time between 1070 and 755 Ma. However, we suggest that it involved regional amphibolite facies metamorphism and deformation, granite magmatism and pegmatite intrusion between c. 1030 and c. 950 Ma. Therefore, the Capricorn Orogen experienced a major phase of tectonic reworking c. 600 Myr later than previously recognized. Our results emphasize the importance of in situ geochronology integrated with petrological studies in order to link the metamorphic history of a terrane with causally related tectonic events. [ABSTRACT FROM AUTHOR]

The effects of various chemical pretreatments on the surface chemistry and adhesion performance of an additive-free styrene-butadiene block copolymer and an additive-free ethylene-propylene elastomer have been studied. Most of the powerful oxidising agents that are effective with hydrocarbon plastics were ineffective in enhancing the adhesion to elastomers despite causing major changes to their surface chemistries. The poor adhesion was attributed to the existence of weak boundary layers. Chlorinated agents were also examined and a new pretreatment for elastomers containing carbon-carbon double bonds has been identified. It was found that a mildly acidified dilute aqueous suspension of Chloramine-T was very effective at enhancing the adhesion performance of styrene butadiene copolymers. [ABSTRACT FROM AUTHOR]

This study aimed to establish the prevalence of psychiatric morbidity among cancer patients' caregivers and to identify markers of risk. Using the Psychiatric Assessment Schedule (a standardized psychiatric interview), the authors assessed 222 caregivers retrospectively. Thirty-one caregivers (14%) had developed an affective disorder during the two years since the patients' initial cancer diagnoses. Caregivers who were the patient's partner were more likely to develop anxiety, depression, or both when their ill spouse had developed these symptoms. Notably, the prevalence of affective disorders among female caregivers was comparable to the prevalence among patients (23%). Female nonpartner caregivers developed disorders as frequently as partners did. Female caregivers with a prior history of affective disorder who reported more illness-related concerns appeared to be at particular risk, providing useful markers for clinical practice. Copyright © 2005 by Elsevier Science (USA). [ABSTRACT FROM AUTHOR]

To determine whether choice of colposcopy or six month cytological surveillance would be beneficial to women with mildly abnormal smears when compared with the national policy of six months surveillance in terms of psychological morbidity.A randomised trial based on the Zelen design.A hospital-based research clinic.Four hundred and seventy-six women who had had a recurrent borderline or mildly dyskaryotic smear on routine cervical screening in primary care.Women were randomised either to six months cytological surveillance or to make a choice between that or colposcopy and were followed up for 1 year.The primary outcome measure was caseness (score≥4) on the General Health Questionnaire at 12 months follow up. Other measures were the Spielberger State and Trait scores, default rates and cytology/colposcopy outcomes.There was no significant difference between the arms for General Health Questionnaire (GHQ) scores and Spielberger State and Trait at 12 months. There was a significant reduction in psychometric morbidity between baseline and 12 months in both arms. Overall rates of default from the protocol were the same in both arms, but default that led to uncertain ascertainment of cervical pathology was greater in the no-choice arm.This trial indicates that having choice did not impact favourably or harmfully on anxiety or feelings of wellbeing. If a patient is anxious, allowing the patient to choose immediate colposcopy may be preferable because it will improve ascertainment of underlying disease in a group who are more likely to default. [ABSTRACT FROM AUTHOR]

SHRIMP (Sensitive High-Resolution Ion MicroProbe) analytical procedures have been developed to enable dating of the small, early diagenetic xenotime overgrowths that commonly occur on zircons in siliciclastic sedimentary rocks. The method will be particularly useful in Precambrian terranes, where diagenetic xenotime dating could play a role equivalent to biostratigraphic dating in the Phanerozoic. Reliable 207Pb/206Pb data are more readily obtained than 206Pb/238U, which also favours application to the Precambrian. However, it is demonstrated that 206Pb/238U dating of larger overgrowths (>10 μm) is also viable and applicable to Phanerozoic samples. SHRIMP Pb/Pb geochronology of authigenic xenotime in an unmetamorphosed Palaeoproterozoic sandstone in the Kimberley Basin has constrained diagenesis to a precision of ± 7 Ma. In contrast, greenschist-facies metasediments of the Archaean Witwatersrand Basin, South Africa, contain both authigenic and alteration xenotime that record a complex history of growth from early diagenesis to the last major thermal event to affect the basin. [ABSTRACT FROM AUTHOR]

Significant improvements, both in understanding the evolution of zircons and in understanding the geotectonic and metallogenetic evolution of the complex terrain of southern Brazil, are obtained from a SHRIMP geochronology study and reviewed in this paper. The use of backscattered electron and cathodoluminescence images, prior to SHRIMP isotopic determinations, proved of enormous fundamental value for this technique. Zircon is a domainal open-system mineral in many geological conditions; very old domains may be preserved, but the same crystal may show ages of younger tectonic events. Zircons may recrystallise inwards from the rims or outwards from the cores, and also along euhedral high-U or metamict thin zones. Zircons also may be recrystallised during gold-related hydrothermalism, phyllic alteration of granitic rocks. The precise dating of amphibolite dykes can be achieved by the identification and dating of magmatic zircons. Precambrian orogenies are identified along with the intervening intracratonic tectonic cycles of supercontinents in southern Brazil from 3300 to 470 Ma. Granulite protoliths were formed during the Jequié Orogeny (ca 2600 Ma), but extensive arc accretion occurred in the Palaeoproterozoic (ca 2250 Ma) Encantadas Orogeny. Late in the Transamazonian Cycle, granites were formed by crustal melting at about 2000 Ma in the Camboriú Orogeny. Both accretionary and collisional orogenies are also identified in the Neoproterozoic Brasiliano Cycle. These are the accretionary Passinho Orogeny (ca 900 Ma) and São Gabriel Orogeny (ca 700 Ma), that were succeeded by the collisional Dom Feliciano Orogeny (ca 600 Ma). Base-metal and gold deposition occurred in juvenile island arcs and in late orogenic porphyry-copper-type magmatic–hydrothermal settings during the Neoproterozoic. [ABSTRACT FROM AUTHOR]

The liquid crystal properties of binary mixtures of copper- and palladium-containing, twinnedcalamitic, metal organic complexes with the electron acceptor 2,4,7-trinitro-9-fluorenone (TNF) are reported. The smectic A to isotropic transition temperature of the pure metal organic component is increased on mixing. Furthermore, only smectic A behaviour is exhibited by the mixtures compared with smectic A and C phases for the pure metal organic complexes. The stabilization of the smectic A phase in these mixtures is found to be due to a weak charge transfer type interaction. [ABSTRACT FROM AUTHOR]