Full-Depth Recycling Study: Test Track Construction and First Level Analysis of Phase 1 HVS and Laboratory Testing

This first-level report describes the first phase of a study comparing the performance of four different full-depth pavement reclamation strategies, namely pulverization with no stabilization (FDR-NS), stabilization with foamed asphalt and portland cement (FDR-FA), stabilization with portland cement only (FDR-PC), and stabilization with engineered asphalt emulsion (FDR-EE). A literature review, the test track layout and design, stabilization and asphalt concrete mix designs, and test track construction are discussed, as well as results of Heavy Vehicle Simulator (HVS) and laboratory testing. A number of problems were experienced during construction of the FDR-PC and FDR-EE lanes on the test track and consequently only the FDR-NS and FDR-FA lanes and one section of the FDR-PC lane (5 percent measured cement content) were considered satisfactorily uniform for the purposes of accelerated pavement testing. The FDR-FA and FDR-PC sections performed very well and testing on both was terminated long before the terminal rut of 0.5 in. (12.5 mm) or average crack density of 0.8 ft/ft2 (2.5 m/m2 ) were reached (no cracks were observed on either section). The two FDR-NS sections performed acceptably, with the section with the thicker asphalt surfacing (120 mm) outperforming the section with the thinner asphalt surfacing (60 mm), as expected. Terminal rut was reached on both sections, but no cracking was observed. The FDR-EE sections performed poorly, with terminal rut and terminal cracking both reached after a limited number of load repetitions. This poor performance was attributed to problems associated with construction, and consequently no conclusions can be drawn from the test results regarding this stabilization strategy. The advantages of using foamed asphalt with cement and cement only recycling strategies over recycling strategies with no stabilization are clearly evident from the results. A second phase of accelerated pavement testing, full-scale field testing, and additional laboratory testing are planned to collect sufficient data for the development of mechanistic-empirical design criteria (and revised gravel factors) for full-depth reclaimed pavements. However, there is sufficient evidence to show that pavements that are rehabilitated using full-depth reclamation strategies will satisfactorily withstand design traffic levels common in California. Rehabilitation using this approach is quick, has minimal disruption to traffic, reuses all materials, does not require removal of material from the site, and effectively replaces weak base layers, thus preventing reflective cracking that is common in more traditional overlay projects. Based on these conclusions, it is recommended that full-depth reclamation be promoted as an appropriate rehabilitation strategy in California. Future research on partial- and full-depth reclamation should be coordinated to facilitate consistent design and specification documentation, and to facilitate the preparation of a comprehensive guide covering all forms of pavement recycling

Slant cues are processed with different latencies for the online control of movement

For the online control of movement, it is important to respond fast. The extent to which cues are effective in guiding our actions might therefore depend on how quickly they provide new information. We compared the latency to alter a movement when monocular and binocular cues indicated that the surface slant had changed. We found that subjects adjusted their movement in response to three types of information: information about the new slant from the monocular image, information about the new slant from binocular disparity, and information about the change in slant from the change in the monocular image. Responses to changes in the monocular image were approximately 40 ms faster than responses to a new slant estimate from binocular disparity and about 90 ms faster than responses to a new slant estimate from the monocular image. Considering these delays, adjustments of ongoing movements to changes in slant will usually be initiated by changes in the monocular image. The response will later be refined on the basis of combined binocular and monocular estimates of slant. © ARVO

The use of VTE prophylaxis in relation to patient risk profiling(TUNE-IN) Wave 2 Study

KMBackground: The TUNE-IN (The Use of VTE prophylaxis in relatioN to patiEnt risk profiling) study evaluated venous thromboembolism (VTE) risk assessment and prophylaxis in private medical and surgical inpatients in Gauteng Province, South Africa. The study concluded that of the 608 patients enrolled, 54.1% were clinically evaluated to be at risk for VTE. A VTE risk assessment model (RAM), the Caprini score, increased the rate to 74.6%. Objectives: TUNE-IN Wave 2, an extension of TUNE-IN, was conducted on a national level including the public sector, focusing on surgical inpatients. Methods. The study was a national, prospective, non-interventional, multisite, epidemiological disease registry enrolling 453 surgical inpatients. The perceived clinical VTE risk, VTE risk score on Caprini RAM, VTE prophylaxis and clinical details were documented during a baseline visit. A bleeding risk score was provided. Results: Of the cohort, 269 patients (59.4%) were assessed to be at risk for VTE before applying the RAM. All patients (100%), however, were at risk on the RAM score. Early mobilisation and assessment of the VTE risk as low were the most frequent reasons for non-prescription of prophylaxis. Only 15 patients in the private and 2 in the public sector were assessed as having a bleeding risk. Chemoprophylaxis differed between the healthcare sectors, with low-molecular-weight heparin predominating in the private sector and unfractionated heparin being prescribed only in the public sector. Conclusion: VTE risk assessment and prophylaxis need to improve in both the public and the private sectors. A formal RAM will improve identification of patients at risk of VTE

PerfWeb: How to Violate Web Privacy with Hardware Performance Events

The browser history reveals highly sensitive information about users, such as financial status, health conditions, or political views. Private browsing modes and anonymity networks are consequently important tools to preserve the privacy not only of regular users but in particular of whistleblowers and dissidents. Yet, in this work we show how a malicious application can infer opened websites from Google Chrome in Incognito mode and from Tor Browser by exploiting hardware performance events (HPEs). In particular, we analyze the browsers' microarchitectural footprint with the help of advanced Machine Learning techniques: k-th Nearest Neighbors, Decision Trees, Support Vector Machines, and in contrast to previous literature also Convolutional Neural Networks. We profile 40 different websites, 30 of the top Alexa sites and 10 whistleblowing portals, on two machines featuring an Intel and an ARM processor. By monitoring retired instructions, cache accesses, and bus cycles for at most 5 seconds, we manage to classify the selected websites with a success rate of up to 86.3%. The results show that hardware performance events can clearly undermine the privacy of web users. We therefore propose mitigation strategies that impede our attacks and still allow legitimate use of HPEs

Shallow rainwater lenses in deltaic areas with saline seepage

In deltaic areas with saline seepage, freshwater availability is often limited to shallow rainwater lenses lying on top of saline groundwater. Here we describe the characteristics and spatial variability of such lenses in areas with saline seepage and the mechanisms that control their occurrence and size. Our findings are based on different types of field measurements and detailed numerical groundwater models applied in the south-western delta of the Netherlands. By combining the applied techniques we could extrapolate measurements at point scale (groundwater sampling, temperature and electrical soil conductivity (TEC)-probe measurements, electrical cone penetration tests (ECPT)) to field scale (continuous vertical electrical soundings (CVES), electromagnetic survey with EM31), and even to regional scale using helicopter-borne electromagnetic measurements (HEM). The measurements show a gradual mixing zone between infiltrating fresh rainwater and upward flowing saline groundwater. The mixing zone is best characterized by the depth of the centre of the mixing zone <i>D</i><sub>mix</sub>, where the salinity is half that of seepage water, and the bottom of the mixing zone <i>B</i><sub>mix</sub>, with a salinity equal to that of the seepage water (Cl-conc. 10 to 16 g l<sup>−1</sup>). <i>D</i><sub>mix</sub> is found at very shallow depth in the confining top layer, on average at 1.7 m below ground level (b.g.l.), while <i>B</i><sub>mix</sub> lies about 2.5 m b.g.l. The model results show that the constantly alternating upward and downward flow at low velocities in the confining layer is the main mechanism of mixing between rainwater and saline seepage and determines the position and extent of the mixing zone (<i>D</i><sub>mix</sub> and <i>B</i><sub>mix</sub>). Recharge, seepage flux, and drainage depth are the controlling factors

Youth ministry at the margins and/or centre as space of the other: Reflections on the resolutions of the Anglican dioceses in the Western Cape 2017

Youth within the context of faith-based organisations carry with them certain power relations and misconstrued connotations. These power relations and connotations can contribute to alienation and marginalisation. The resolutions taken at the recent synods of the three dioceses within the Western Cape reflect and identify the areas - both liturgical and governance - of marginalisation of youth within the Anglican Church in southern Africa. The resolutions also call on the church governing bodies and the leaders to create safe spaces for the youth to be a central part of the mission of the church. Areas such as liturgy, training and formation, contemporary worship and nurturing relationships are identified within the resolutions. Theological notions of personhood within the Anglican tradition are to be investigated as possible motivations for more acceptable power relations of the youth and leaders and governance structures. What implications do such theological formulations have for the space that the youth occupy within the margins of the church? A critical reflection of the synod resolutions answers such questions and points to some contours for sense making of the youth within the margins of the church from a faith-based organisational perspective

Response to recharge variation of thin rainwater lenses and their mixing zone with underlying saline groundwater

In coastal zones with saline groundwater, fresh groundwater lenses may form due to infiltration of rain water. The thickness of both the lens and the mixing zone, determines fresh water availability for plant growth. Due to recharge variation, the thickness of the lens and the mixing zone are not constant, which may adversely affect agricultural and natural vegetation if saline water reaches the root zone during the growing season. In this paper, we study the response of thin lenses and their mixing zone to variation of recharge. The recharge is varied using sinusoids with a range of amplitudes and frequencies. We vary lens characteristics by varying the Rayleigh number and Mass flux ratio of saline and fresh water, as these dominantly influence the thickness of thin lenses and their mixing zone. Numerical results show a linear relation between the normalised lens volume and the main lens and recharge characteristics, enabling an empirical approximation of the variation of lens thickness. Increase of the recharge amplitude causes increase and the increase of recharge frequency causes a decrease in the variation of lens thickness. The average lens thickness is not significantly influenced by these variations in recharge, contrary to the mixing zone thickness. The mixing zone thickness is compared to that of a Fickian mixing regime. A simple relation between the travelled distance of the centre of the mixing zone position due to variations in recharge and the mixing zone thickness is shown to be valid for both a sinusoidal recharge variation and actual records of daily recharge data. Starting from a step response function, convolution can be used to determine the effect of variable recharge in time. For a sinusoidal curve, we can determine delay of lens movement compared to the recharge curve as well as the lens amplitude, derived from the convolution integral. Together the proposed equations provide us with a first order approximation of lens characteristics using basic lens and recharge parameters without the use of numerical models. This enables the assessment of the vulnerability of any thin fresh water lens on saline, upward seeping groundwater to salinity stress in the root zone

Характеристика загрязнения прибрежных вод у Карадагского заповедника по данным оптических измерений

На основе анализа данных оптических наблюдений в рамках комплексных океанографических экспедиций, проведенных сотрудниками ИнБЮМ НАНУ и МГИ НАНУ 22, 23 мая 2007 г. и 21, 22 июля 2009 г. в прибрежных водах Черного моря у Карадагского заповедника, выполнены оценки загрязнения рассматриваемой акватории растворенным органическим веществом искусственного происхождения и растворенными нефтепродуктами. Определены концентрации, источники и пути распространения суммарной взвеси и загрязняющих веществ. Зафиксирован рост степени загрязнения заповедной акватории в течение двух последних лет.На основі аналізу даних оптичних спостережень у рамках комплексних океанографічних експедицій, проведених співробітниками ІнБЮМ НАНУ та МГІ НАНУ 22, 23 травня 2007 р. та 21, 22 липня 2009 р. у прибережних водах Чорного моря біля Карадазького заповідника, виконано оцінки забруднення розглянутої акваторії розчиненою органічною речовиною штучного походження та розчиненими нафтопродуктами. Визначено концентрації, джерела та шляхи поширення сумарної зваженої речовини та забруднюючих речовин. Зафіксовано зростання ступеню забруднення заповідної акваторії протягом двох останніх років.On the base of analysis of optical observations’ data within the framework of complex oceanographic expeditions, undertaken by employers of IBSS and MHI of National academy of sciences of Ukraine on 22, 23 May 2007 and 21, July 22 2009 in the coastal waters of the Black sea beside the Karadag reserve, estimations of water borne contaminations with dissolved organic material by man made birth and dissolved oil are executed. The concentrations, sources and the ways of the total suspended matter and polluting material spreading are defined. Increase in pollution percentage in waters of the reserve is fixed for two last years

Preconditioning of mesenchymal stromal cells with low-intensity ultrasound: influence on chondrogenesis and directed SOX9 signaling pathways

Background: Continuous low-intensity ultrasound (cLIUS) facilitates the chondrogenic differentiation of human mesenchymal stromal cells (MSCs) in the absence of exogenously added transforming growth factor-beta (TGFβ) by upregulating the expression of transcription factor SOX9, a master regulator of chondrogenesis. The present study evaluated the molecular events associated with the signaling pathways impacting SOX9 gene and protein expression under cLIUS. Methods: Human bone marrow-derived MSCs were exposed to cLIUS stimulation at 14 kPa (5 MHz, 2.5 Vpp) for 5 min. The gene and protein expression of SOX9 was evaluated. The specificity of SOX9 upregulation under cLIUS was determined by treating the MSCs with small molecule inhibitors of select signaling molecules, followed by cLIUS treatment. Signaling events regulating SOX9 expression under cLIUS were analyzed by gene expression, immunofluorescence staining, and western blotting. Results: cLIUS upregulated the gene expression of SOX9 and enhanced the nuclear localization of SOX9 protein when compared to non-cLIUS-stimulated control. cLIUS was noted to enhance the phosphorylation of the signaling molecule ERK1/2. Inhibition of MEK/ERK1/2 by PD98059 resulted in the effective abrogation of cLIUS-induced SOX9 expression, indicating that cLIUS-induced SOX9 upregulation was dependent on the phosphorylation of ERK1/2. Inhibition of integrin and TRPV4, the upstream cell-surface effectors of ERK1/2, did not inhibit the phosphorylation of ERK1/2 and therefore did not abrogate cLIUS-induced SOX9 expression, thereby suggesting the involvement of other mechanoreceptors. Consequently, the effect of cLIUS on the actin cytoskeleton, a mechanosensitive receptor regulating SOX9, was evaluated. Diffused and disrupted actin fibers observed in MSCs under cLIUS closely resembled actin disruption by treatment with cytoskeletal drug Y27632, which is known to increase the gene expression of SOX9. The upregulation of SOX9 under cLIUS was, therefore, related to cLIUS-induced actin reorganization. SOX9 upregulation induced by actin reorganization was also found to be dependent on the phosphorylation of ERK1/2. Conclusions: Collectively, preconditioning of MSCs by cLIUS resulted in the nuclear localization of SOX9, phosphorylation of ERK1/2 and disruption of actin filaments, and the expression of SOX9 was dependent on the phosphorylation of ERK1/2 under cLIUS

THE DEVELOPMENT OF A FRAMEWORK FOR THE USE OF INFORMATION AND COMMUNICATION TECHNOLOGY IN THE CLASSROOM

Published ThesisThe aim of this study was to explore the development of a framework for the use of Information and Communication Technology in the classroom. It was clear from the study that teachers lack Information and Communication Technology (ICT) capability, and should therefore be trained and retrained. While they are expected to produce quality education, they are also expected to receive training which is a time-consuming exercise and often makes teachers want to give up on the implementation of ICT in the classroom. If teachers were to use ICT in the classroom, it would change the passive role of the learners in which they merely receive knowledge to a more active role where they construct their own knowledge. In addition, teachers would have the opportunity to connect with experts, and have access to global resources. Teachers should be motivated to use ICT to improve the quality of their teaching. This, together with proper ICT skills, would ensure the effective use of ICT. To ascertain the effective use of ICT by teachers, research was conducted in ten secondary schools in Bloemfontein. A random sample of 30 secondary school teachers was drawn from ten schools. A mixed methods approach was used to the collect data, i.e. qualitative (questionnaires) and qualitative (interviews). Questionnaires were administered to the participants and were then followed by unstructured interviews. The research participants were selected randomly from the study population in an unbiased manner to produce quantifiable, reliable data. Mix methods designs provide advantages when a researcher is exploring complex research questions. The findings of this study revealed that teachers have a positive attitude towards the use of ICT, and that it enables better teaching standards and educational outcomes. Teachers also have barriers that hinder them from using ICT in the classroom