Stream dynamics between 1 AU and 2 AU: A detailed comparison of observations and theory

A radial alignment of three solar wind stream structures observed by IMP-7 and -8 (at 1.0 AU) and Voyager 1 and 2 (in the range 1.4 to 1.8 AU) in late 1977 is presented. It is demonstrated that several important aspects of the observed dynamical evolution can be both qualitatively and quantitatively described with a single-fluid 2-D MHD numerical model of quasi-steady corotating flow, including accurate prediction of: (1) the formation of a corotating shock pair at 1.75 AU in the case of a simple, quasi-steady stream; (2) the coalescence of the thermodynamic and magnetic structures associated with the compression regions of two neighboring, interacting, corotating streams; and (3) the dynamical destruction of a small (i.e., low velocity-amplitude, short spatial-scale) stream by its overtaking of a slower moving, high-density region associated with a preceding transient flow. The evolution of these flow systems is discussed in terms of the concepts of filtering and entrainment

A low-mass faraday cup experiment for the solar wind

Faraday cups have proven to be very reliable and accurate instruments capable of making 3-D velocity distribution measurements on spinning or 3-axis stabilized spacecraft. Faraday cup instrumentation continues to be appropriate for heliospheric missions. As an example, the reductions in mass possible relative to the solar wind detection system about to be flown on the WIND spacecraft were estimated. Through the use of technology developed or used at the MIT Center for Space Research but were not able to utilize for WIND: surface-mount packaging, field-programmable gate arrays, an optically-switched high voltage supply, and an integrated-circuit power converter, it was estimated that the mass of the Faraday Cup system could be reduced from 5 kg to 1.8 kg. Further redesign of the electronics incorporating hybrid integrated circuits as well as a decrease in the sensor size, with a corresponding increase in measurement cycle time, could lead to a significantly lower mass for other mission applications. Reduction in mass of the entire spacecraft-experiment system is critically dependent on early and continual collaborative efforts between the spacecraft engineers and the experimenters. Those efforts concern a range of issues from spacecraft structure to data systems to the spacecraft power voltage levels. Requirements for flight qualification affect use of newer, lighter electronics packaging and its implementation; the issue of quality assurance needs to be specifically addressed. Lower cost and reduced mass can best be achieved through the efforts of a relatively small group dedicated to the success of the mission. Such a group needs a fixed budget and greater control over quality assurance requirements, together with a reasonable oversight mechanism

Perceptions of South African academic instructors toward the teaching and learning of anatomy

Background: Reflecting on teaching is commonly cited as a fundamental practice for personal and professional development. Educational research into the scholarship of teaching and learning anatomy includes engaging in discipline specific literature on teaching, reflecting on individual teaching methods and communicating these findings to peers. The aim of this paper was to formally assess the opinions of senior anatomy instructors regarding the state of anatomical knowledge at their respective institutions. Materials and methods: An open-ended questionnaire was devised consisting of eight direct questions seeking opinions on anatomy teaching, knowledge, potential educational developments and general thoughts on the teaching of anatomy to medical students. These were distributed to senior Anatomy Faculty (identified by the author by their affiliation with the Anatomical Society of Southern Africa) based at the eight national medical schools within the country. Results and Conclusions: A number of key themes emerged. Most senior faculty felt that the standard of medical education at their respective institutions was “good.” However, emphasis was also placed on the “quality of teaching” incorporating clinical scenarios. There were also indications that staff are split into those that are keen to do research and those that are happy to provide teaching to medical students as their primary function. Several challenges such as time constraints within the curricula, lack of cadavers to reinforce knowledge and lack of appropriately qualified staff were highlighted. Recommendations included fostering partnerships with both clinicians and medical scientists into the anatomy curriculum thus improving teaching and research

Reflective journals: unmasking student perceptions of anatomical education

Background: In medical education, reflection has been considered to be a core skill in professional competence. The anatomy laboratory is an ideal setting for faculty/ student interaction and provides invaluable opportunities for active learning and reflection on anatomical knowledge. Materials and methods: This study was designed to record student attitudes regarding human cadaveric dissection, explore their experiences of anatomy through an analysis of their journal-reflective writings and determine whether this type of creative writing had a beneficial effect on those students who chose to complete them. A total of 75 journals from Medical and Allied Health Science students were collected and analysed. Results: Results were categorised according to the following themes: (i) Dissecting room stressors (27.6%); (ii) Educational value of dissection (26.3%); (iii) Appreciation, Gratitude, Respect and Curiosity for the cadaver (18.9%); (iv) Positive and negative sentiments expressed in the dissecting room (25.8%); (v) Benefit of alternate teaching modalities (4.6%); (vi) Spirituality/Religious Beliefs (3.7%); (vii) Shared humanity and emotional bonds (3.69%); (viii) Acknowledgement of human anatomical variations (3.2%); (ix) Beauty and complexity of the human body (1.8%) and (x) Psychological detachment (0.9%). Students appreciated the opportunity to share their emotions and reflect on the humanistic dimension of anatomy as a subject. Student reflections illustrated clearly their thoughts and some of the difficult issues with which they wrestled. Conclusions: The anatomy laboratory is seen as the budding clinician’s first encounter with a patient, albeit a cadaver. This was the first time that reflective journals were given to students in the discipline. Reflective journals allow students to express themselves in an open-ended and creative fashion. It also assists students to integrate anatomy and clinical medicine and assists in applying their basic anatomical knowledge in an authentic, yet safe environmen

Stress appraisal, coping, and work engagement among police recruits: an exploratory study.

This study investigated the influence of stress appraisal and coping on work engagement levels (Absorption, Vigour, and Dedication) of police recruits. Participants were 387 men, ages 20 to 33 yr. (M = 24.1, SD = 2.4), in their last month of academy training before becoming police officers. Partially in support of predictions, work engagement was associated with Stressor control perceived, but not Stress intensity experienced over a self-selected stressor. Although the three dimensions of work engagement were explained by Stressor control and coping, Absorption was the dimension better explained by these variables. Police recruits reporting higher Absorption, Vigour, and Dedication reported using more Active coping and less Behavioural disengagement. Results showed that stress appraisal and coping are important variables influencing work engagement among police recruits. Findings suggested that future applied interventions fostering work engagement among police recruits should reinforce perceptions of control over a stressor as well as Active coping strategies

Outcomes of Shoulder Arthroplasty Performed for Postinfectious Arthritis.

Background: The purpose of this study was to evaluate the functional outcomes, infection rate, and complications associated with shoulder arthroplasty for sequelae of prior septic arthritis. Methods: This is a retrospective cohort study of 17 patients who underwent shoulder arthroplasty for sequelae of septic arthritis. Patients were analyzed for patient-reported outcomes, complications, and reoperations. Results: The 17 patients in this cohort were an average age of 65.4 ± 12.2 years old, were 58.8% male, and had an average body mass index of 27.9 ± 4.1 kg/m Conclusions: Shoulder arthroplasty after septic arthritis had inconsistent functional outcomes and high complication rates but no reinfection

Interplanetary flow systems associated with cosmic ray modulation in 1977 - 1980

The hydromagnetic flow configurations associated with cosmic ray modulation in 1977 to 1980 were determined using solar wind plasma and magnetic field data from Voyagers 1 and 2 and Helios 1. The modulation was related to two types of large scale systems of flows: one containing a number of transients such as shocks, post shock flows and magnetic clouds; the other consisting primarily of a series of quasi-stationary flows following interaction regions containing a stream interface and often bounded by a forward reverse shock pair. Each of the three major episodes of cosmic ray modulation was characterized by the passage of the system of transient flows. Plateaus in the cosmic ray intensity time profile were associated with the passage of systems of corotating streams

Long head of biceps brachii tendon and transverse humeral ligament morphometry and their associated pathology

Background: As a dynamic stabiliser and flexor of the glenohumeral joint, the long head of the biceps brachii tendon (LHBBT) is further stabilised by the retinacular activities of the transverse humeral ligament (THL). Materials and methods: The LHBBT and THL which were obtained from a total of 40 cadaveric upper limb specimens (n = 80; females: 36, males: 44; right: 40, left: 40), were bilaterally dissected and subjected to morphometric evaluation. Results: The results are in millimetres. LHBBT length: 81.99 ± 21.28 right, 79.73 ± 17.27 left; 79.82 ± 19.66 male, 82.14 ± 19.03 female; LHBBT width: 4.28 ± 1.31 right, 4.67 ± 1.43 left; 4.35 ± 1.17 male, 4.63 ± 1.60 female; THL length: 20.91 ± 5.24 right, 21.19 ± 6.63 left; 21.52 ± 5.71 male, 20.48 ± 5.92 female; THL width: 16.65 ± 6.92 right, 16.63 ± 7.49 left; 16.83 ± 6.65 male, 16.40 ± 7.84 female. With larger LHBBT length observed on the right side and larger LHBBT width observed on the left side; both parameters appeared to be distinctly longer in female individuals. On the contrary, the THL length and width were evidently greater in male individuals, with larger lengths and widths present on the left and right sides respectively. Conclusions: These findings may contribute to South African literature and to clinical knowledge as these parameters are important in the successful outcomes of tenotomy, tenodesis and shoulder-related procedures