Faraday and Cotton-Mouton Effects of Helium at λ=1064\lambda = 1064 nm

We present measurements of the Faraday and the Cotton-Mouton effects of helium gas at $\lambda =~1064$\,nm. Our apparatus is based on an up-to-date resonant optical cavity coupled to longitudinal and transverse magnetic fields. This cavity increases the signal to be measured by more than a factor of 270\,000 compared to the one acquired after a single path of light in the magnetic field region. We have reached a precision of a few percent both for Faraday effect and Cotton-Mouton effect. Our measurements give for the first time the experimental value of the Faraday effect at $\lambda$=\,1064\,nm. This value is compatible with the theoretical prediction. Concerning Cotton-Mouton effect, our measurement is the second reported experimental value at this wavelength, and the first to agree at better than 1$\sigma$ with theoretical predictions.Comment: Submitted to Phys. Rev.

Levinsonian seasons in the life of Steve Jobs: A psychobiographical case study

Steve Jobs (1955-2011) was not only a businessman renowned for his legacy of technological innovation and entrepreneurship. His life history indicates eras or seasons as prankster, hippie, family man, and cancer fighter. This psychobiographical case study entailed a psychosocial-historical analysis of Jobs’s development interpreted through Levinson’s theory of the human life cycle, and was undertaken against the background of Merleau-Ponty’s ontological philosophy that elucidates a human science phenomenology where the individual cannot be separated from his/her social world. The primary objective of this study was to uncover the eras and transitions within Jobs’s life cycle. The secondary objective was to illustrate and test the relevance of Levinsonian theory as applied to Jobs’s life. Jobs’s life cycle was uncovered through an analysis of published and publically available materials, which included both primary and secondary data sources. Alexander’s psychobiographical model was employed to extract salient evidence for analysis. A conceptual psychosocial-historical matrix guided the analysis. Key findings indicate that the central components of Jobs’s life and social world (e.g., his occupation, family, friendships and terminal illness) had a significant influence on his psychosocial development. In conclusion, Jobs’s development generally conformed to Levinsonian theory as well as to Merleau-Ponty’s phenomenological ontology and illustrated the relevance of these conceptual models for understanding the individual’s connectedness to his/her social world

Emily Hobhouse’s Psychosocial Developmental Trajectory as Anti-War Campaigner: A Levinsonian Psychobiography

The aim of this psychobiography was to uncover, reconstruct and illustrate significant trajectories of psychosocial development and historical events over the lifespan of Emily Hobhouse (1860-1926). The British-born Hobhouse later became an anti-war campaigner and social activist who exposed the appalling conditions of the British concentration camps during the Anglo-Boer War (1899-1902), as evidenced by primary and secondary historical data. Purposive sampling was used to select Hobhouse as a significant and exemplary subject. Levinson’s four eras or seasons of lifespan development served as the theoretical psychological approach. The study was undertaken against the background of Merleau-Ponty’s ontological philosophy that elucidates a human science phenomenology where the individual cannot be separated from her social world. Alexander’s model of identifying salient biographical themes was utilized and a conceptual psycho-historical framework, based on both the life cycle theory of Levinson and significant historical periods throughout Hobhouse’s life, was employed to assist with data gathering, categorisation, and analyses. The findings highlight significant psychosocial and historical events in the life of Hobhouse that shaped her development as an anti-war campaigner. These include: The role of her strong-willed and determined mother; the denial of an opportunity to study and pursue a formal education; her management of painful feelings of abandonment and grief; the care of her father during his illness and his eventual death; the abrupt ending of her failed romantic relationship; her networking capacity; and her open-mindedness and capacity for independent humanitarian thought. Against the philosophical background of Merleau-Ponty’s phenomenological ontology, Levinson’s theory and eras proved valuable in identifying these particular psychosocial life experiences and historical events as having shaped Emily Hobhouse into an antiwar campaigner

Status of the BMV experiment

In this contribution we present the status of the BMV experiment whose goal is to measure the vacuum magnetic birefringence

Solamargine, a bioactive steroidal alkaloid isolated from Solanum aculeastrum induces non-selective cytotoxicity and Pglycoprotein inhibition

Abstract: Background: Solanum aculeastrum fruits are used by some cancer sufferers as a form of alternative treatment. Scientific literature is scarce concerning its anticancer activity, and thus the aim of the study was to assess the in vitro anticancer and P-glycoprotein inhibitory potential of extracts of S. aculeastrum fruits. Furthermore, assessment of the combinational effect with doxorubicin was also done. Methods: The crude extract was prepared by ultrasonic maceration. Liquid-liquid extraction yielded one aqueous and two organic fractions. Bioactive constituents were isolated from the aqueous fraction by means of column chromatography, solid phase extraction and preparative thin-layer chromatography. Confirmation of bioactive constituent identity was done by nuclear magnetic resonance and ultra-performance liquid chromatography mass spectrometry. The crude extract and fractions were assessed for cytotoxicity and P-glycoprotein inhibition in both cancerous and non-cancerous cell lines using the sulforhodamine B and rhodamine-123 assays, respectively. Results: Both the crude extract and aqueous fraction was cytotoxic to all cell lines, with the SH-SY5Y neuroblastoma cell line being most susceptible to exposure (IC50 = 10.72 μg/mL [crude], 17.21 μg/mL [aqueous]). Dose-dependent P-glycoprotein inhibition was observed for the crude extract (5.9 to 18.9-fold at 100 μg/mL) and aqueous fraction (2.9 to 21.2 at 100 μg/mL). The steroidal alkaloids solamargine and solanine were identified. While solanine was not bioactive, solamargine displayed an IC50 of 15.62 μg/mL, and 9.1-fold P-glycoprotein inhibition at 100 μg/mL against the SH-SY5Y cell line. Additive effects were noted for combinations of doxorubicin against the SH-SY5Y cell line. Conclusions: The crude extract and aqueous fraction displayed potent non-selective cytotoxicity and noteworthy P-glycoprotein inhibition. These effects were attributed to solamargine. P-glycoprotein inhibitory activity was only present at concentrations higher than those inducing cytotoxicity, and thus does not appear to be the likely mechanism for the enhancement of doxorubicin’s cytotoxicity. Preliminary results suggest that non-selective cytotoxicity may hinder drug development, however, further assessment of the mode of cell death is necessary to determine the route forward

The development and relevance of the Resiliency Model of Family Stress, Adjustment and Adaptation

The study of family resilience has gained momentum within the field of family psychology over the last two decades. This paper focuses on the development of the Resiliency Model of Family Stress, Adjustment and Adaptation, which has a long history and is substantiated by research dating back to 1946. The factors comprising the model have been empirically tested, and related measuring instruments have been developed in order to evaluate resiliency factors within the family context. Each of the Resiliency Model’s antecedent models is outlined here, while its potential relevance to the South African context is also debated

Burnout and its correlates in South African clinical and counselling psychologists

This article explores burnout and its correlates among South African psychologists. A random sample of 238 clinical and counselling psychologists completed internet surveys that included a biographical questionnaire, the Maslach Burnout Inventory, and the Brief Coping Orientations to Problems Experienced. Results indicated that approximately half of the participants showed moderate to high levels of burnout. Different combinations of coping strategies predicted the three components of burnout. The biographical variables of age, gender, weekly client hours, years in practice, and medical aid payment difficulties were significant predictors of burnout. Recommendations are made to improve the emotional well-being of South African psychologists

Quantum vacuum magneto-optics

International audienc

Is the beta3-adrenoceptor (ADRB3) a potential target for uterorelaxant drugs?

The management of premature birth still remains unsatisfactory. Since the relative lack of efficiency and/or safety of current tocolytic agents have been highlighted, it is necessary to develop new uterorelaxant drugs deprived of important maternal and foetal side effects. Our work reported in this review focuses on a potential new target for tocolytic drugs, the β3-adrenoceptor (ADRB3). This third type of ADRB is shown to be present and functional in human myometrium. We demonstrated that ADRB3 agonists are able to inhibit in-vitro spontaneous contractions of myometrial strips, via a cyclic AMP-mediated pathway. Furthermore, we established that ADRB3 is the predominant subtype over the ADRB2 in human myometrium and that its expression is increased in near-term myometrium, compared to non-pregnant myometrium. Finally, we reported that contrary to ADRB2, the human myometrial ADRB3 is resistant to long-term agonist-induced desensitisation. These compelling data confirm the clinical potential interest of ADRB3 agonists in the pharmacological management of preterm labour

Subcortical brain volumes in young infants exposed to antenatal maternal depression: Findings from a South African birth cohort.

BACKGROUND: Several studies have reported enlarged amygdala and smaller hippocampus volumes in children and adolescents exposed to maternal depression. It is unclear whether similar volumetric differences are detectable in the infants' first weeks of life, following exposure in utero. We investigated subcortical volumes in 2-to-6 week old infants exposed to antenatal maternal depression (AMD) from a South African birth cohort. METHODS: AMD was measured with the Beck Depression Inventory 2nd edition (BDI-II) at 28-32 weeks gestation. T2-weighted structural images were acquired during natural sleep on a 3T Siemens Allegra scanner. Subcortical regions were segmented based on the University of North Carolina neonatal brain atlas. Volumetric estimates were compared between AMD-exposed (BDI-II ⩾ 20) and unexposed (BDI-II < 14) infants, adjusted for age, sex and total intracranial volume using analysis of covariance. RESULTS: Larger volumes were observed in AMD-exposed (N = 49) compared to unexposed infants (N = 75) for the right amygdala (1.93% difference, p = 0.039) and bilateral caudate nucleus (left: 5.79% difference, p = 0.001; right: 6.09% difference, p < 0.001). A significant AMD-by-sex interaction was found for the hippocampus (left: F(1,118) = 4.80, p = 0.030; right: F(1,118) = 5.16, p = 0.025), reflecting greater volume in AMD-exposed females (left: 5.09% difference, p = 0.001, right: 3.54% difference, p = 0.010), but not males. CONCLUSIONS: Volumetric differences in subcortical regions can be detected in AMD-exposed infants soon after birth, suggesting structural changes may occur in utero. Female infants might exhibit volumetric changes that are not observed in male infants. The potential mechanisms underlying these early volumetric differences, and their significance for long-term child mental health, require further investigation