Pion production in high energy cosmic ray collisions

Calculations on pion energy and angle distribution in center of hydrodynamic inelastic model for nucleon-nucleon collisio

Short SULF1/SULF2 splice variants predominate in mammary tumours with a potential to facilitate receptor tyrosine kinase-mediated cell signalling

The relative roles of SULF1 and SULF2 enzymes in tumour growth are controversial, but short SULF1/SULF2 splice variants predominate in human mammary tumours despite their non-detectable levels in normal mammary tissue. Compared with the normal, the level of receptor tyrosine kinase (RTK) activity was markedly increased in triple-positive mammary tumours during later stages of tumour progression showing increased p-EGFR, p-FGFR1 and p-cMet activity in triple-positive but not in triple-negative tumours. The abundance of catalytically inactive short SULF1/SULF2 variants permits high levels of HS sulphation and thus growth driving RTK cell signalling in primary mammary tumours. Also observed in this study, however, was increased N-sulphation detected by antibody 10E4 indicating that not only 6-O sulphation but also N-sulphation may contribute to increased RTK cell signalling in mammary tumours. The levels of such increases in not only SULF1/SULF2 but also in pEGFR, pFGFR1, p-cMet and Smad1/5/8 signalling were further enhanced following lymph node metastasis. The over-expression of Sulf1 and Sulf2 variants in mammary tumour-derived MDA-MB231 and MCF7 cell lines by transfection further confirms Sulf1-/Sulf2-mediated differential modulation of growth. The short variants of both Sulf1 and Sulf2 promoted FGF2-induced MDA-MB231 and MCF7 in vitro growth while full-length Sulf1 inhibited growth supporting in vivo mammary tumour cell signalling patterns of growth. Since a number of mammary tumours become drug resistant to hormonal therapy, Sulf1/Sulf2 inhibition could be an alternative therapeutic approach to target such tumours by down-regulating RTK-mediated cell signalling

Modeling Changes in the In-Migration Patterns of Northern Saskatchewan Communities : a Log-Linear Approach

Les auteurs examinent les changements dans les types historiques de migrations au sein des petites communautés frontières du nord de la Saskatchewan durant les périodes 1927-1960, 1961-1970 et 1971-1976. Des problèmes apparaissent lorsqu'on tente de formuler des modèles d'interaction spatiale dans les régions frontières, ou en voie de développement, en particulier le faible volume de migration et le fait que certains termes agglomérés sont impropres lorsqu'utilisés comme mesures de degré d'attraction et de répulsion des communautés. Comme procédure alternative, on utilise une méthode log-linéaire, laquelle identifie, par une analyse à dimensions multiples d'une matrice de données classifiées, les composantes dans les processus d'interaction spatiale. Les résultats initiaux montrent que le sexe de l'immigrant n'a pas d'effet sur la tendance à immigrer, et que les types spatiaux d'immigration n'ont pas changé d'une période à l'autre.This paper examines changes in the historical pattern of in-migration to small frontier communities in northern Saskatchewan in three time periods: 1927-1960, 1961-1970 and 1971-1976. The problems associated with spatial interaction modeling in a developing or frontier region are noted, particularly the low volume of in-migration and the inappropriateness of mass terms as surrogate measures of nodal attractiveness and propulsiveness. As an alternative, a log-linear approach is adopted, whereby multidimensional contingency-table analysis of categorical data reveals structural components in the spatial-interaction process. Initial results indicate that the gender of the migrant has no effect on the propensity to migrate and that spatial patterns of in-migration have not changed over time

Implementing and scaling-up Stepping Stones in KwaZulu-Natal, South Africa: Lessons from working in informal settlements

KwaZulu-Natal (KZN), a major epicenter of the South African HIV epidemic, has large informal settlements where thousands of people live. The settlements are often underserved by municipal services and lack accessible health care. Given high rates of HIV, there is a critical need to assess the successes and challenges of implementing HIV prevention and treatment in this context. Stepping Stones is a widely used life-skills training intervention focused on curbing gender-based violence and reducing HIV risk. The program addresses issues such as communication about HIV, relationship skills, and assertiveness. The manual-based curriculum encourages participants to engage in critical reflection through role-playing and group dialogue. Previous evaluations of Stepping Stones in South Africa found significant reductions in intimate partner violence and herpes simplex virus-2, and improvements in couple communication and negotiation. Under Project SOAR, the Population Council and the MatCH Research Unit of the University of the Witwatersrand conducted program evaluations in 18 selected informal settlements in KZN. This brief focuses on the experiences, challenges, successes, and perceived effects of implementing (and scaling up) Stepping Stones in the informal settlement setting

Acorn production in the Missouri Ozarks

Cover title.Includes bibliographical references

Solving Navigational Uncertainty Using Grid Cells on Robots

To successfully navigate their habitats, many mammals use a combination of two mechanisms, path integration and calibration using landmarks, which together enable them to estimate their location and orientation, or pose. In large natural environments, both these mechanisms are characterized by uncertainty: the path integration process is subject to the accumulation of error, while landmark calibration is limited by perceptual ambiguity. It remains unclear how animals form coherent spatial representations in the presence of such uncertainty. Navigation research using robots has determined that uncertainty can be effectively addressed by maintaining multiple probabilistic estimates of a robot's pose. Here we show how conjunctive grid cells in dorsocaudal medial entorhinal cortex (dMEC) may maintain multiple estimates of pose using a brain-based robot navigation system known as RatSLAM. Based both on rodent spatially-responsive cells and functional engineering principles, the cells at the core of the RatSLAM computational model have similar characteristics to rodent grid cells, which we demonstrate by replicating the seminal Moser experiments. We apply the RatSLAM model to a new experimental paradigm designed to examine the responses of a robot or animal in the presence of perceptual ambiguity. Our computational approach enables us to observe short-term population coding of multiple location hypotheses, a phenomenon which would not be easily observable in rodent recordings. We present behavioral and neural evidence demonstrating that the conjunctive grid cells maintain and propagate multiple estimates of pose, enabling the correct pose estimate to be resolved over time even without uniquely identifying cues. While recent research has focused on the grid-like firing characteristics, accuracy and representational capacity of grid cells, our results identify a possible critical and unique role for conjunctive grid cells in filtering sensory uncertainty. We anticipate our study to be a starting point for animal experiments that test navigation in perceptually ambiguous environments

Ever and repeat HIV testing rates among male and female clients: Findings from a reproductive health services integration project in South Africa

Background. HIV testing rates have increased in recent years. Repeat testing is recommended to identify and treat new HIV infections timeously. However, there are limited data on repeat HIV testing, especially in South Africa (SA).Objectives. To provide data on repeat HIV testing rates in males and females in a district in SA.Methods. A sexual and reproductive health (SRH) service integration model was implemented in seven healthcare facilities in eThekwini District, KwaZulu-Natal Province, SA, between 2009 and 2011. HIV testing data were collected from male and female clients attending these facilities, prior to (baseline) and after the implementation (endline) of the 3-year health services integration intervention.Results. There were 230 clients at baseline (195 female, 35 male) and 200 at endline (169 female, 31 male). High ever-tested rates were reported at baseline (females 95.4%, males 74.3%) and endline (females 91.7%, males 87.1%), with large increases in male testing rates over time. In addition, high increases were seen between baseline and endline among those who had tested more than once and more than twice in their lifetime. Increases between baseline and endline testing rates were highest in HIV testing services (HTS) (37.0 - 93.3% for clients who had tested more than once, and 11.1 - 53.3% for those who had tested more than twice).Conclusions. HIV testing and repeat testing increased over time, especially in males and in HTS. Promotion and integration of SRH services are critical to facilitate improved health-seeking behaviour and HIV testing of both male and female clients. They are also important for continued access to HTS at multiple service delivery points

Using Prior Knowledge and Student Engagement to Understand Student Performance in an Undergraduate Learning-to-Learn Course

This study examined prior knowledge and student engagement in student performance. Log data were used to explore the distribution of final grades (i.e., weak, good, excellent final grades) occurring in an elective under-graduate course. Previous research has established behavioral and agentic engagement factors contribute to academic achievement (Reeve, 2013). Hierarchical logistic regression using both prior knowledge and log data from the course revealed: (a) the weak-grades group demonstrated less behavioral engagement than the good-grades group, (b) the good-grades group demonstrated less agentic engagement than the excellent-grades group, and (c) models composed of both prior knowledge and engagement measures were more accurate than models composed of only engagement measures. Findings demonstrate students performing at different grade-levels may experience different challenges in their course engagement. This study informs our own instructional strategies and interventions to increase student success in the course and provides recommendations for other instructors to support student success

Believe me! Why tesla’s recent alleged malfunction further highlights the need for transparent dialogue

On November the 13th, 2022 video footage was released purportedly showing a Tesla Model Y malfunctioning by speeding through the streets of a Chinese city killing two people. Video footage such as this has the potential to undermine trust in AVs. While Tesla has responded by stating they will get to the “truth,” there are questions as to how this truth is to be decided, and perhaps more importantly how the public can trust either Tesla or negative press. We explore the “facts” of the incident and discuss the challenges of building trust in new AVs systems based on transparency. In this article we argue that transparency is more than simply getting to the “truth.” It is fostering a relational dialogue between the facts and stakeholder. Using O’Brien’s window metaphor, this article explores the need for AV manufacturers to consider the content of such incidents, the different perceptions of stakeholders, and the medium through which the content is presented. Apart from the need for independent crash investigators, there is a need for AV manufacturers to go beyond simply’ getting to the truth’ and to engage with the public responsibly

Demonstration of the spatial separation of the entangled quantum side-bands of an optical field

Quantum optics experiments on "bright" beams typically probe correlations between side-band modes. However the extra degree of freedom represented by this dual mode picture is generally ignored. We demonstrate the experimental operation of a device which can be used to separate the quantum side-bands of an optical field. We use this device to explicitly demonstrate the quantum entanglement between the side-bands of a squeezed beam