Siphonochilus aethiopicus (Zingiberaceae): observations on floral and reproductive biology

A taxonomic revision for the Flora of Southern Africa of Siphonochilus (Zingiberaceae) awaits publication (R.M. Smith, RBG, Edin., pers. comm. to ABC, 1987). In this revision the two southern African species, S. aethiopicus (Schweinf.) B.L. Burtt and S. natalensis (Schltr. & Schum.) Wood & Franks will be united. For the purposes of this article this conspecificity is assumed. S. aethiopicus has a distribution in Africa southwards from Senegal and Ethiopia to the Transvaal. Futher south wild populations are not now known, the species having disappeared from the natural flora of Natal. Rhizomes are extensively used in traditional African medicine and cultural practices. Floral and reproductive biology is poorly documented, but important if cultivated stocks in southern Africa are to be maintained. Monitoring of plants under cultivation and semi-natural conditions did not support the record of polygamy within the species. One type of flower only was produced by an individual rhizome. Bisexual flowers may mature to fruits containing viable seed that will germinate in situ. Ovaries of female flowers did not develop, suggesting apomixis does not operate in seed production. The internal surfaces of the staminodial tubes of bisexual flowers bore scattered glandular trichomes; those of female flowers densely placed multicellular papillae. Bisexual and female flowers are thus strikingly different in detailed structure as well as in general morphological form

Perceived stress among dental students at the University of the Western Cape

Introduction: A high prevalence of stress among dental students has been reported. Aim: To determine perceived stress among dental students at the University of the Western Cape. Method: A self-administered questionnaire to students (n=411) was used to collect data. Variables measured included demographic characteristics of students and their perceived stress in the dental environment using the Dental Environment Stress (DES) survey and the Maslach Burnout Inventory (MBI). Results: The response rate was 78%. Respondents were in the 18 to 21 age category; mostly female (n=207); multilingual, with 63% having English as their home language. Huge problems identified from the DES were lack of time for relaxation, inadequate breaks during the day, fear of failing a year or module, work load, inconsistency between clinical supervisors and patients being late for appointments. The MBI found high EE (28.91), low DP (7.13) and high PA (30.06) scores. Fourth year students experienced the highest degree of stress on the DES and MBI. Conclusion: Stressors identified are consistent with international dental literature. Levels of stress increased over the academic years and peaked in the fourth year. Stressors experienced may impact student academic and future professional development, motivating a need for intervention at Faculty level.DHE

Individual job redesign:job crafting interventions in healthcare

In two quasi-experimental studies – Study 1 among medical specialists (N = 119) and Study 2 among nurses (N = 58) – we tested the impact of a general and a specific job crafting intervention on health care professionals’ well-being and (objective and subjective) job performance. Both groups of participants received training and then set personal job crafting goals for a period of three weeks. The results of a series of repeated measures analyses showed that both interventions were successful. Participation in the job crafting intervention groups were associated with increases in job crafting behaviors, well-being (i.e., work engagement, health, and reduced exhaustion), and job performance (i.e., adaptive, task, and contextual performance) for the medical specialists and nurses relative to the control groups. Though we did not find a significant intervention effect for objective performance, we conclude that job crafting is a promising job redesign intervention strategy that individual employees can use to improve their well-being and job performance.</p

High moisture tempering of corn before flaking: effects on bacterial contamination from houseflies and fecal shedding in finishing cattle Broce, A.B.; Gordon, C.M.; Sindt, J.J.; Depenbusch, Brandon E.; Drouillard, James S.; Phebus, Randall K

Tempered and non-tempered steam-flaked corn samples along with total mixed rations containing either tempered or non-tempered steam-flaked corn were exposed to flies and the environment for 21 hours. Exposure to flies and the environment increased (P\u3c0.05) generic E. coli, non-E. coli coliforms, total coliforms, and total plate count for the steamflaked corn samples independent of tempering. Tempering corn before steam-flaking increased total plate counts. Exposure to the environment and flies did not significantly (P\u3e0.05) alter microbial counts of total mixed rations regardless of tempering (Table 1). Generic E. coli coliforms were greater in total mixed rations when the corn was tempered, both before and after exposure to flies and the environment (P\u3c0.05). Similarly, total microbial plate counts were higher in steam-flaked corn samples when the corn was tempered (P\u3c0.05). A significant increase in response to grain tempering was also noted in non-E. coli coliforms and total microbial plate counts for the total mixed ration samples after exposure (Table 1). Following the initial experiments, 96 finishing beef steers were used to evaluate the effects of tempering steam-flaked corn on acid-resistant E. coli and total fecal coliforms. On day 56 of the feeding period, fecal samples were collected and analyzed for total and acidresistant E. coli and coliforms. No significant treatment difference was observed in the total fecal coliforms (P\u3e0.05), but acid-resistant (pH 2) non-E. coli and total fecal coliforms (Table 2) were lower in feces of cattle fed the tempered grain than those fed non-tempered grain

Recent advance in high manufacturing readiness level and high temperature CMOS mixed-signal integrated circuits on silicon carbide

A high manufacturing readiness level silicon carbide (SiC) CMOS technology is presented. The unique process flow enables the monolithic integration of pMOS and nMOS transistors with passive circuit elements capable of operation at temperatures of 300 °C and beyond. Critical to this functionality is the behaviour of the gate dielectric and data for high temperature capacitance–voltage measurements are reported for SiO2/4H-SiC (n and p type) MOS structures. In addition, a summary of the long term reliability for a range of structures including contact chains to both n-type and p-type SiC, as well as simple logic circuits is presented, showing function after 2000 h at 300 °C. Circuit data is also presented for the performance of digital logic devices, a 4 to 1 analogue multiplexer and a configurable timer operating over a wide temperature range. A high temperature micro-oven system has been utilised to enable the high temperature testing and stressing of units assembled in ceramic dual in line packages, including a high temperature small form-factor SiC based bridge leg power module prototype, operated for over 1000 h at 300 °C. The data presented show that SiC CMOS is a key enabling technology in high temperature integrated circuit design. In particular it provides the ability to realise sensor interface circuits capable of operating above 300 °C, accommodate shifts in key parameters enabling deployment in applications including automotive, aerospace and deep well drilling

Independent genomic polymorphisms in the PknH serine threonine kinase locus during evolution of the Mycobacterium tuberculosis Complex affect virulence and host preference

Species belonging to the Mycobacterium tuberculosis Complex (MTBC) show more than 99% genetic identity but exhibit distinct host preference and virulence. The molecular genetic changes that underly host specificity and infection phenotype within MTBC members have not been fully elucidated. Here, we analysed RD900 genomic region across MTBC members using whole genome sequences from 60 different MTBC strains so as to determine its role in the context of MTBC evolutionary history. The RD900 region comprises two homologous genes, pknH1 and pknH2, encoding a serine/threonine protein kinase PknH flanking the tbd2 gene. Our analysis revealed that RD900 has been independently lost in different MTBC lineages and different strains, resulting in the generation of a single pknH gene. Importantly, all the analysed M. bovis and M. caprae strains carry a conserved deletion within a proline rich-region of pknH, independent of the presence or absence of RD900. We hypothesized that deletion of pknH proline rich-region in M. bovis may affect PknH function, having a potential role in its virulence and evolutionary adaptation. To explore this hypothesis, we constructed two M. bovis ‘knock-in’ strains containing the M. tuberculosis pknH gene. Evaluation of their virulence phenotype in mice revealed a reduced virulence of both M. bovis knock-in strains compared to the wild type, suggesting that PknH plays an important role in the differential virulence phenotype of M. bovis vs M. tuberculosis

Perceived stressors of oral hygiene students in the dental environment

University students are exposed to a multitude of stressors that may impact on their performance. The nature of health sciences education generally involves early engagement with patients and communities, which may add to the stressors inherent to university life. There is sparse information on stressors in the oral hygiene educational environment. Objective. To determine perceived stressors and the level of burnout among oral hygiene students at the University of the Western Cape, Cape Town, South Africa. A descriptive, cross-sectional study design was used. The study sample included all students in the Bachelor of Oral Health (BOH) degree during 2012 (N=89). A self-administered questionnaire was used to gather data. Three parameters were measured, i.e. (i) demographic characteristics; (ii) perceived sources of stress, using a modified Dental Environment Stress (DES) questionnaire; and (iii) burnout, using the Maslach Burnout Inventory (MBI). Respondents were mostly female (74%) and primarily in the 18 - 25-year age group (92%). First- and 2nd-year students identified fear of failing and study load as major stressors. Stressors related to a lack of basic needs were identified as major stressors by 25% of 1st-year students. Third-year students identified clinical quotas, supervision and patients being late as major stressors. MBI scores indicated that students were not at risk for burnout; however, most students (66.2%) scored high on emotional exhaustion (EE). Oral hygiene students identified stressors in their learning environment. There was a progressive increase in EE across academic years. The results suggest that interventions should be tailored for specific academic year groups

Effective metrics in the non-minimal Einstein-Yang-Mills-Higgs theory

We formulate a self-consistent non-minimal five-parameter Einstein-Yang-Mills-Higgs (EYMH) model and analyse it in terms of effective (associated, color and color-acoustic) metrics. We use a formalism of constitutive tensors in order to reformulate master equations for the gauge, scalar and gravitational fields and reconstruct in the algebraic manner the so-called associated metrics for the Yang-Mills field. Using WKB-approximation we find color metrics for the Yang-Mills field and color-acoustic metric for the Higgs field in the framework of five-parameter EYMH model. Based on explicit representation of these effective metrics for the EYMH system with uniaxial symmetry, we consider cosmological applications for Bianchi-I, FLRW and de Sitter models. We focus on the analysis of the obtained expressions for velocities of propagation of longitudinal and transversal color and color-acoustic waves in a (quasi)vacuum interacting with curvature; we show that curvature coupling results in time variations of these velocities. We show, that the effective metrics can be regular or can possess singularities depending on the choice of the parameters of non-minimal coupling in the cosmological models under discussion. We consider a physical interpretation of such singularities in terms of phase velocities of color and color-acoustic waves, using the terms ``wave stopping'' and ``trapped surface''.Comment: 25 pages, no figures, accepted to Annals of Physic

Factorization Breaking in Dijet Photoproduction with a Leading Neutron

The production of dijets with a leading neutron in ep-interactions at HERA is calculated in leading order and next-to-leading order of perturbative QCD using a pion-exchange model. Differential cross sections for deep-inelastic scattering (DIS) and photoproduction are presented as a function of several kinematic variables. By comparing the theoretical predictions for DIS dijets to recent H1 data, the pion flux factor together with the parton distribution functions of the pion is determined. The dijet cross sections in photoproduction show factorization breaking if compared to the H1 photoproduction data. The suppression factor is S = 0.48 (0.64) for resolved (global) suppression.Comment: 16 pages, 5 figure

Education for sustainable development: A study in adolescent perception changes towards sustainability following a strategic planning-based intervention-the young persons' plan for the planet program

© 2019 by the authors. In 2016, the United Nations (UN) launched the 17 Sustainable Development Goals (SDGs) as a framework for sustainable development and a sustainable future. However, the global challenge has been to engage, connect, and empower communities, particularly young people, to both understand and deliver the 17 SDGs. In this study, we show the benefit of a strategic planning-based experiential learning tool, the Young Persons' Plan for the Planet (YPPP) Program, to improve the underlying competencies of Australian and Mauritian adolescents in increasing understanding and delivering the SDGs. The study was conducted with 300 middle to senior high school students, in 25 schools throughout Australia and Mauritius, over an 18-month period. The intervention included the development of research, strategic planning, management, STEM (Science Technology, Engineering, Maths) and global competency skills in the students, to enable them to build and deliver regional and national SDG plans. Research methods included pre- and post-intervention testing of the attitudes of these students to sustainable development outcomes and compared these attitudes to subsets of scientists and the Australian national population. Our results, from both qualitative and quantitative evidence, demonstrate significant improvements in these adolescents' appreciation of, and attitudes towards, the SDGs and sustainable outcomes, across a range of key parameters. The results from the 76 students who attended the International Conference in Mauritius in December 2018 demonstrate significant improvements in mean levels of understanding, and attitudes of the students towards the SDGs awareness (+85%), understanding/engagement (+75%), motivation (+57%), and action orientation/empowerment (+66%). These changes were tested across a range of socio-demographic, geographic, and cultural parameters, with consistent results. These findings have significant implications for the challenge of sustainable education and achieving community engagement and action towards the SDGs in Australia and Mauritius, particularly for young people. As the intervention can be replicated and scaled, the findings also highlight the opportunity to extend both the research and this type of experiential learning intervention across both broader geographies and other generation and community segments