Some key topographic and material controls on debris flows in Scotland

Debris-flow phenomena were investigated at six study sites across upland Scotland using a combination of laboratory and field-based analyses. In agreement with previous research, higher spatial frequencies of debris-flow paths were measured in areas underlain by coarse-grained intrusive igneous and arenaceous sedimentary bedrocks compared with metamorphic and extrusive igneous geologies. A strong relationship between critical state friction angle of sampled initiation zone soils and spatial frequency of debris-flow paths suggests that this trend is attributable to generally lower shear strengths in sandier hillslope material generated from coarser grained bedrocks. Topographic controls on debris-flow susceptibility are demonstrated by higher numbers of debris-flow paths at sites with persistently steep upper slopes (=30°) and a higher occurrence of potential initiation zones. Strong correlation between debris-flow magnitude and slope length shows that longer mass movements tend to produce higher volumes of material and terminal deposits that travel further at the slope foot. In the cases studied here this reflects greater opportunity for accumulation of fresh material during the transport phase, particularly in the case of long channelized flows. The highest levels of hazard are likely to occur where these topographic and material characteristics conducive to heightened susceptibility and magnitude coincide.</p

The role of strategic leadership in effective strategy implementation: Perceptions of South African strategic leaders

A review of the literature reveals that strategy implementation isan important component of the strategic management process.Research indicates that the ability to implement a strategy is viewedas considerably more important than strategy formulation, andthat strategy implementation, rather than strategy formulation, isthe key to superior organisational performance. However, the highfailure rate of strategy implementation efforts is well documented,and many barriers to effective strategy implementation exist. A lackof leadership, and specifically strategic leadership, at the top ofthe organisation has been identified as one of the major barriersto effective strategy implementation. In turn, strategic leadership isalso viewed as a key driver to effective strategy implementation.In the light of the identified problem, the primary objective of thisstudy was to investigate the perceived role of strategic leadershipin strategy implementation in South African organisations. Theconclusion is that strategic leadership positively contributes toeffective strategy implementation in South African organisations

Revival of the magnetar PSR J1622-4950: observations with MeerKAT, Parkes, XMM-Newton, Swift, Chandra, and NuSTAR

New radio (MeerKAT and Parkes) and X-ray (XMM-Newton, Swift, Chandra, and NuSTAR) observations of PSR J1622-4950 indicate that the magnetar, in a quiescent state since at least early 2015, reactivated between 2017 March 19 and April 5. The radio flux density, while variable, is approximately 100x larger than during its dormant state. The X-ray flux one month after reactivation was at least 800x larger than during quiescence, and has been decaying exponentially on a 111+/-19 day timescale. This high-flux state, together with a radio-derived rotational ephemeris, enabled for the first time the detection of X-ray pulsations for this magnetar. At 5%, the 0.3-6 keV pulsed fraction is comparable to the smallest observed for magnetars. The overall pulsar geometry inferred from polarized radio emission appears to be broadly consistent with that determined 6-8 years earlier. However, rotating vector model fits suggest that we are now seeing radio emission from a different location in the magnetosphere than previously. This indicates a novel way in which radio emission from magnetars can differ from that of ordinary pulsars. The torque on the neutron star is varying rapidly and unsteadily, as is common for magnetars following outburst, having changed by a factor of 7 within six months of reactivation.Comment: Published in ApJ (2018 April 5); 13 pages, 4 figure

Mental Toughness in South African Youth: Relationships With Forgivingness and Attitudes Towards Risk

Young people are particularly vulnerable to health risk behaviors and interpersonal violence, stimulating scholars’ attention towards identifying factors that may reduce the likelihood that these actions will occur. Associated with positive outcomes in a variety of domains, mental toughness in young people might protect them from engaging in potentially deleterious interpersonal or health-risk behaviors, while potentially promoting positive psychological behaviors. Within this framework, the present study investigated the relationships between mental toughness, attitudes towards physical and psychological risk-taking, and trait forgiveness in a sample of 123 (males = 54, females = 69) South African youth (M age = 23.97 years, SD = 4.46). Univariate and multivariate analyses indicated higher levels of mental toughness were associated with being more forgiving, (η2pηp2 = .036), perceiving physical risk-taking more positively (η2pηp2 = .062), but having more negative attitudes towards psychological risk-taking (η2pηp2 = .036). These findings give credence to mental toughness as a psychological characteristic involved in youth risk-taking perceptions and interpersonal functioning. Future research might explore the integration of mental toughness into the development of future youth risk behavior interventions

Developing a Learner's Corpus: the case of a First-Year Module in Mathematics

A learner's corpus is a body of writing for use by a student whose first language is not (in this case) English to improve his/her use of (in this case) academic scientific terminology. In this case study, a learner's corpus was developed for a first-year mathematics module for students in the biological sciences. Lecturers struggle with big classes and a fairly high failure rate which they have addressed in a variety of ways. The learner's corpus is one of an array of support mechanisms built into the teaching-learning process and aims to support the development of academic literacy in this module in particular. In the process of developing and refining this learner's corpus it was compared to Coxhead's Academic Word List to determine whether a gen-eral academic word list may not include enough terms to render tailor-made learner's corpora unnecessary. The study concludes that the most frequent terms used in this module either do not appear in the Academic Word List or have such a specialised meaning that general academic sup-port on the basis of the word list would probably not be very useful for students. Keywords: learner's corpus, academic word list, academic language support, mathematics word list, pedagogic application of corpora, case stud

Improvement of common bacterial blight resistance in South African dry bean cultiver teebud

Common bacterial blight (CBB) caused by Xanthomonas axonopodis pv. phaseoli is an important seed-borne disease of dry beans in South Africa.&nbsp; Development of resistant cultivars is considered the best control measurement for the disease. Backcross breeding was used to improve&nbsp; BB resistance in the small white canning bean, cv. Teebus, using resistance sources XAN 159 and Wilk 2. High resistance levels in near-isogenic lines, developed in two independent breeding programmes, indicated successful&nbsp; transfer of resistance from both sources. Presence of SCAR-markers, SU91 and BC420, in 35 of 39 XAN 159 derived Teebus lines and all lines derived from Wilk 2, confirmed successful resistance transfer. AFLP studies conducted to determine genetic relatedness of two near-isogenic Teebus lines, showed a similarity of 96.2% with the maximum similarity between&nbsp; these lines and Teebus being 93.1%. One cultivar, Teebus-RCR2 with yield similar to Teebus and improved resistance to CBB has been released from the programme