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The aim of this study was to profile the psychological coping, learning potential and career-related interests of 251 candidates for operational force military selection for the South African National Defence Force (SANDF) – 26 of whom were successful in the selection. Data on their sense of meaning, learning potential and career-related interest were gathered using standardised measures supplemented with open-ended responses. The data were analysed to compare the profiles of the successful candidates against those not selected. The selected group showed significantly higher mean scores on meaningfulness and learning potential, and lower scores for career-related interest in law and medicine. Findings suggest that psychological coping, learning potential and career-related preference information can be used to refine the selection of operational force military candidates.

In South Africa, an empirical characterisation of crumb rubber modified (CRM) bituminous binders has historically been the only means of predicting their performance in pavement layers, short of constructing pavement test sections. An improved characterisation is provided by means of rheological analysis using a dynamic shear rheometer (DSR). However, the heterogeneous morphology of CRM bitumen makes it a challenge to test using current methods and equipment. DSR testing of CRM bitumen requires a plate gap adjustment to avoid any influence by the rubber particles. This has been done by monitoring the effect of changing the DSR plate gap setting on the measured linear visco-elastic properties of the binder. An adjusted gap was adopted for rheological measurements so as to characterise CRM bitumen properties with ageing. But, the incomplete recovery of CRM binder from asphalt/seals makes it impossible to monitor the rheological properties of the in situ binder within a pavement layer. This has led to indire...

Three-dimensional tire-pavement contact loads of two truck tires—a new-generation wide-base tire (WBT) and a dual tire assembly (DTA)—were measured and analyzed. Extreme and typical values of tire inflation pressure (552, 690, 758, and 862 kPa) and tire loading (26, 35, 44, 62, and 79 kN) were considered in the experimental program. The measurements were performed with the stress-in-motion Mk IV system at the Council for Scientific and Industrial Research in South Africa. Peak values in three directions were compared, and the importance of tangential contact stresses was highlighted. In addition, characteristic variations of the measurements in the longitudinal, transverse, and vertical directions were identified. A function depending on two regression parameters, applied load, and distance along the contact length was proposed to represent the contact load in the vertical and transverse directions. An analysis was performed on the measurements to obtain the regression parameters, and a simplified procedu...

Evaluation of the crushing (or compression) failure and associated surface deformation of lightly cementitious (stabilised) materials used for base/sub-base course in pavements has been well established in the South African pavement design practice since the 1990s. This paper presents a re-evaluation of this earlier work, focusing on expanding the empirically derived crushing performance relationships (i.e. transfer functions or damage laws) for lightly cementitious materials at in situ moisture conditions, i.e. without the adverse effect of additional or artificial water infiltration into the lightly cementitious base, which limited the practical application of the original transfer functions for significant rutting. The re-evaluation was undertaken to determine whether the original crush initiation relationship was reasonable for as-built moisture conditions and also to develop practical advanced crushing damage relationships for various rut depths developing within the base, based on the measured respo...

Copyright: 2013 Elsevier. This is an ABSTRACT ONLY. The definitive version is published in Measurement, vol. 46(7), pp 2155-2173

Optimization of road pavement design, especially close to the surface of the pavement, requires a more rational approach, which will inevitably include modeling of truck tire-road contact stresses. Various road-surfacing failures have been recorded as evidence that the traditional road pavement engineering tire model idealized by a single uniformly distributed vertical contact stress of circular shape may be inadequate to properly explain and assist in the design against road surface failures. This article therefore discusses the direct measurement of three-dimensional (3D) tire pavement contact stresses using a flatbed sensor system referred to as the “Stress-In-Motion” (SIM) system. The SIM system (or device) consists of multiple conically shaped steel pins, as well as an array of instrumented sensors based on strain gauge technology. The test surface is textured with skid resistance approaching that of a dry asphalt layer. Full-scale truck tires have been tested since the mid-1990s, and results show that 3D tire contact stresses are nonuniform and that the footprint is often not of circular shape. It was found that especially the vertical shape of contact stress distribution changes, mainly as a function of tire loading and associated tire inflation pressures. In overloaded/underinflated cases, vertical contact stresses are the highest toward the edges of the tire contact patch. Higher inflation pressures at lower loads, on the other hand, result in maximum vertical stresses toward the center portion of the tire contact patch. These differences in shape and magnitude need to be incorporated into modern mechanistic-empirical road pavement design tools. Four different idealized tire models were used to represent a single tire type to demonstrate effects of tire modeling on the road pavement response of a typical South African pavement structure incorporating a relatively thin asphalt surfacing. Only applied vertical stress was used for the analyses. It was found that the fatigue life of the road surface layer can be reduced by as much as 94% and strain energy of distortion be increased by a factor of 2.8, depending on the characteristics of the tire model input selected for road pavement design and analysis.

Weak interlayers within the upper structural layers of road pavements are specifically prohibited in most road-building specifications. However, such layers are extremely common and often lead to premature pavement distress. Heavy Vehicle Simulator (HVS) evaluation indicates that the presence of such layers within the structural layers of a flexible/semi-flexible pavement is far more deleterious than is commonly appreciated. These effects are modelled using examples based an HVS testing and simplistic mechanistic pavement analyses. In particular, weak upper base courses of lightly cemented pavement under thin bituminous surfacing may lead to severe surfacing and upper base failure within a matter of months after opening to traffic, not excluding failure during construction. The causes of these adverse conditions, together with simple detection methods during construction and analyses of their effects on the structural capacity of flexible and semi-rigid (cemented) road pavements, are briefly discussed. Methodologies are available to detect and investigate the existence of these weak layers in cemented pavement layers. Analysis were done on a typical recycled hot mix asphalt (HMA) pavement, cemented base pavement and a granular base pavement, with and without these weak layers and interface conditions. The analyses focused on the strain energy of distortion (SED) as a pavement response parameter indicating the potential for structural damage. SED shows some potential for quantifying relative distortional effects of these weak layers and/or weak interfaces within flexible and semi-flexible pavements. In this paper a very brief overview of above is given.

An important element of Accelerated Pavement Testing (APT) is the selection of appropriate test tyre(s) to be used for APT testing. By far the majority of full scale (or scaled) APT devices uses pneumatic rubber tyres. Tyres differ not only in size, but also in composition stiffness, tyre tread patters, etc. Together with selected tyre loading scenarios, tyre inflation pressure plays a very important role and which is often neglected during planning the APT research. The thinner the flexible surfacing layers or the higher the pavement temperature within the asphalt surfacing and base layers, the more important the tyre-pavement interaction becomes. This is so because of the magnitude and non-uniformity of the tyre-pavement contact within the tyre contact patch, amongst others. The general (traditional) assumption is that the tyre-pavement contact is uniformly distributed within the tyre contact patch. A multitude of studies indicated that it is not only the tyre tread pattern and surface friction that influences these tyre contact stress patterns, but mainly the tyre loading/inflation pressure combination. In order to address these issues, the concept of “tyre fingerprinting” is proposed for APT users. Each tyre load/inflation pressure combination produces a different contact pattern inside the contact patch. For example, tyre loadings combined with high inflation pressure results in peak stresses (higher than inflation pressure) to develop in the centre portion of the contact patch, where relatively low inflation pressures combined with relatively high tyre loadings as often used to accelerate testing during APT research, may result in tyre edge loading/stresses, also much higher than the tyre inflation pressures. The aim of this paper is to address and clarify above with respect to selecting the appropriate tyre loading/inflation pressure levels for flexible pavement research using APT devices.

Orientation: Motivational and coping resources were explored within a military context by means of a mixed-methods survey study involving a group of Special Forces candidates. Research purpose: The purpose was to compare selected and not-selected candidates in terms of their sense of coherence, hardiness, locus of control and self-efficacy and to explore what they considered important for success in the selection process. Motivation for the study: Because of high attrition rates in Special Forces selection, the evaluation of the role of motivation and coping resources in terms of possible predictive utility could benefit the organisation from a logistical, financial and efficiency point of view. Research design, approach and method: A mixed-method cross-sectional survey design was used to assess an all-male candidate group ( N = 73). The selected and not-selected groups were compared with regard to their sense of coherence, hardiness, locus of control and self-efficacy mean scores. Main findings: No statistically significant differences were found between the mean scores of the two groups concerning the quantitative measures used. Practical/managerial implications: The quantitative measures generally showed acceptable coefficient alpha reliabilities. Although no statistically significant mean differences were found between the groups, candidates showed high levels of sense of coherence, high levels of self-efficacy and average levels of hardiness and internal locus of control. The qualitative data confirmed the relevance of the quantitative constructs and pointed to additional aspects already considered in preparation for and during the selection process. Contribution/value-add: The results provide information regarding the constructs and measures used in a military context.

Three-dimensional (3D) tire–pavement contact stresses for two types of tires used by the truck industry (new generation wide-base tire [WBT] and dual-tire assembly [DTA]) were measured and compared. The testing matrix was composed of five loads () (26.6, 35.5, 44.4, 62.1, and 79.9 kN) and four tire inflation pressures (ߪ ௢ ) (552, 690, 758, and 862 kPa). The equipment used for measuring the 3D- contact stresses is described along with the testing procedure and the methodology followed during data processing. The effect of applied load and tire-inflation pressure on the variation of longitudinal, transverse, and vertical CONTACT STRESSES along the contact length of each tire type was analyzed. Differences in the distribution and magnitude of the aforementioned stresses were observed between WBT and DTA; these differences are an important factor linked to pavement damage caused by each tire configuration. This experimental effort is part of a national study to evaluate the effect of WBT on pavement damage and compare it to that of DTA.

Título del número: La música como patrimonio : identidad y mestizaje "En este texto se argumenta que la música es capaz de relacionarse simbólicamente con cualquier tipo de significado, y al ser performativa y al carecer de una verbalidad inherente, el espacio para que las subjetividades oigan lo que quieren oír se hace más amplio. De esta manera los repertorios musicales vistos como patrimonios íntimos y privados, pueden ser compartidos y utilizados desde las necesidades particulares de distintas etnicidades. En este caso se ilustrará como ejemplo las chirimías del carnaval de Riosucio - Caldas..."

We present Raman data for the series of high-temperature superconducting compounds YBa{sub 2{minus}{ital x}}La{sub {ital x}}Cu{sub 3}O{sub 7} with {ital x} = 0, 0.1, 0.2, 0.3, 0.4, and 0.5. We have investigated the dependence of frequencies and linewidths of the five Raman-active {ital A}{sub {ital g}} modes on {ital x}. For {ital x}=0.4 a structural phase transition from orthorhombic to tetragonal takes place. With decreasing orthorhombicity ({ital a}{minus}{ital b})/({ital a}+{ital b}) the O(2)-O(3)-in-phase and O(2)-O(3)-out-of-phase modes increase their coupling, contrary to what one may expect. This can be understood in terms of a negative contribution of the chain fragments to the coupling matrix element between these two modes, which we estimate to be {minus}52.9 cm{sup {minus}1}. With increasing {ital x}, two additional features become more pronounced in the Raman spectra. The first is a broad hump in the vicinity of the Ba peak and the second a peak at 570 cm{sup {minus}1}. Both peaks are assigned to a phonon-density-of-states contribution to the Raman spectra induced by the Ba-La disorder. {copyright} {ital 1996 The American Physical Society.}

The Government's commitment to providing a more consumer-oriented service is clearly demonstrated by its recent announcement of a Performance League Table for hospitals, and empowerment of the consumer through The Patient's Charter. The provision of a fetal assessment day care unit at the Mayday Hospital, Croydon, is a sensitive response to the needs of the local community and the Government's commitment to a high quality and cost-effective service.

Se realizó un diseño experimental para determinar el efecto de una solución del arilo del fruto de Blighia sapida (Merey del Diablo), sobre la concentración total de glucógeno en mejillones Geukensia demissa del Lago de Maracaibo, estado Zulia, Venezuela. Se utilizaron seis tratamientos: cinco experimentales y uno control. Los experimentales consistieron en exponer a grupos de cuatro mejillones a dosis de 1000, 1500, 2000, 2500 y 3000 mg/L de la solución durante 24 horas; a diferencia del control, que no incluyó dicha solución. De cada tratamiento se realizaron cuatro repeticiones. La concentración de glucógeno se determinó por la prueba cuantitativa de antrona, realizando las lecturas en un espectrofotómetro de luz visible a 620 nm. El análisis de varianza indicó que la solución del arilo del fruto de B. sapida en dosis de 1500 mg/L afecta de manera significativa (P < 0,0007) la concentración de glucógeno en los mejillones, aumentándola. A study was made to determine the effect of a Blighia sapida fruit arillus solution, upon total glycogen concentration of Geukensia demissa mussels from Maracaibo Lake, Zulia state, Venezuela. It was used six treatments: five experimental and one control. Experimental treatments consisted in submitting groups of four mussels to doses of 1000. 1500, 2000, 2500 and 3000 mg/L respectively, for 24 hours. Control treatment did not include B. sapida fruit arillus solution. Each treatment was repeated four times. Glycogen concentration was determined by anthrone quantitative test, reading the samples with a visible light spectrophotometer at 620 nm. Variance analysis showed that 8. sapida fruit arillus solution at 1500 mg/L Significative affects mussel glycogen concentration (P < 0.0007), increasing it. 143 - 148 gfernand@luz.ve Bimestral

CONTENIDO Editorial Nesti de Alonso, Ana Edad y peso a la pubertad en novillas criollo limonero Age and weight at puberty of Criollo Limonero heifers Montiel Urdaneta, Néstor S. Efecto luteoprotector del tratamiento GnRH en vacas mestizas repetidoras con cuerpo luteo sub - funcional Luteoprotector effect of GnRh therapy in cross - bred repeatbreeder cows with subfunction of the corpus luteum González Stagnaro, Carlos; Madrid Bury, Ninoska; Morales, Jesús y Marín, Douglas Suplementación preparto de novillas mestizas durante la época seca. II sexo del becerro y comportamiento productivo Prepartum supplementation of crossbred heifers during the dry season. II Calf sex and reproductive Performance Portillo, Germán; Soto B., Eleazar; Román Bravo, Rafael y Ventura, Max Suplementación preparto de novillas mestizas durante la época seca. III comportamiento productivo Prepartum supplementation of crossbred heifers during the dry season. III reproductive Performance Portillo, Germán; Soto B., Eleazar; Román Bravo, Rafael y Ventura, Max Comparación de métodos de conservación para muestras de sangre y leche en la determinación de la concentración de progesterona Comparison of methods to preserve blood and milk simples for progesterone concentration determination Araujo F., Omar; Betancourt, R. y Romero, Maritza Evaluación de los efectos de la distomatosis hepática bovina sobre la eficiencia reproductiva y producción lechera Evaluation of the effects of the bovine hepatic distomatosis on the reproductive efficiency and milk production Chirinos, Angel R. y Chirinos de M., Nelly Irene Ultraestructura de la telangiectasia hepática bovina Ultraestructure of bovine liver telangiectasis Soto, Jorge A. y Delgado, Federico Ultraestructura del sinusoide hepático del bovino con referencia especial a las células de Ito, células almacenadotas de grasa o lipocitos Ultrastructure of the bovine liver sinusoid width special referent to Ito’s, fat storing cells or lipocytes Soto, Jorge A. y Delgado, Federico Evaluación de la leucaena leucocephala sobre la pigmentación de la yema de huevos de gallinas ponedoras y la influencia en su productividad Evaluation of leucaena leucocephala as egg yolk pigmentant of laying hens and its influence on productivity Parra de Solano, Neyda M. Efecto experimental de la ingestación del fruto del enterolobium cyclocarpum (Kara-Kara) en el ganado bovino Experimental effects of the Enterolobium cyclocarpum (Kara-Kara) fruit in cattle Negrón G., Gilberto; Parra, Omaira; Avila P., Nancy y Hoest Siberio, Armando Hepatotoxicidad de la maleza heliotropium indicum L. (Rabo de Alacrán) familia boraginaceae Hepatoxicity of the leed Heliotropium indicum L. (Rabo de alacrán) boraginaceae family. Morris de Sanz, Joyce y Román Bravo, Rafael y Zambrano, Omar Mensajes Institucionales 68 - 73 bimestral Nivel analítico

By definition, the subjective probability distribution of a random event is revealed by the (‘rational’) subject's choice between bets — a view expressed by F. Ramsey, B. De Finetti, L. J. Savage and traceable to E. Borel and, it can be argued, to T. Bayes. Since hypotheses are not observable events, no bet can be made, and paid off, on a hypothesis. The subjective probability distribution of hypotheses (or of a parameter, as in the current ‘Bayesian’ statistical literature) is therefore a figure of speech, an ‘as if’, justifiable in the limit. Given a long sequence of previous observations, the subjective posterior probabilities of events still to be observed are derived by using a mathematical expression that would approximate the subjective probability distribution of hypotheses, if these could be bet on. This position was taken by most, but not all, respondents to a ‘Round Robin’ initiated by J. Marschak after M. H. De-Groot's talk on Stopping Rules presented at the UCLA Interdisciplinary Colloquium on Mathematics in Behavioral Sciences. Other participants: K. Borch, H. Chernoif, R. Dorfman, W. Edwards, T. S. Ferguson, G. Graves, K. Miyasawa, P. Randolph, L. J. Savage, R. Schlaifer, R. L. Winkler. Attention is also drawn to K. Borch's article in this issue.

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