ELT HARMONI: Image Slicer Preliminary Design

Harmoni is the ELT's first light visible and near-infrared integral field spectrograph. It will provide four different spatial scales, ranging from coarse spaxels of 60 x 30 mas best suited for seeing limited observations, to 4 mas spaxels that Nyquist sample the diffraction limited point spread function of the ELT at near-infrared wavelengths. Each spaxel scale may be combined with eleven spectral settings, that provide a range of spectral resolving powers from R 3500 to R 20000 and instantaneous wavelength coverage spanning the 0.47 - 2.45 {\mu}m wavelength range of the instrument. The consortium consists of several institutes in Europe under leadership of Oxford University. Harmoni is starting its Final Design Phase after a Preliminary Design Phase in November, 2017. The CRAL has the responsibility of the Integral Field Unit design linking the Preoptics to the 4 Spectrographs. It is composed of a field splitter associated with a relay system and an image slicer that create from a rectangular Field of View a very long (540mm) output slit for each spectrograph. In this paper, the preliminary design and performances of Harmoni Image Slicer will be presented including image quality, pupil distortion and slit geometry. It has been designed by CRAL for Harmoni PDR in November, 2017. Special emphases will be put on straylight analysis and slice diffraction. The optimisation of the manufacturing and slit geometry will also be reported.Comment: 13 pages, 19 figures, 4 tables, Submitted to SPIE Astronomical Telescopes and Instrumentatio

Geologien - bind 2 i serien "Naturen i Danmark"

Med det andet bind i Gyldendals store fembindsværk om Danmarks natur har både den almene læser og den geologisk vidende fået en aldeles fremragende bog

Concurrent projects : how many can you handle?

The number of projects a person can handle simultaneously is a relevant factor in strategic planning and in project portfolio management. Internationally the de facto standard seems to be that a person should not work on more than two or three projects simultaneously; but several factors could influence this figure. Empirical evidence indicates that, in some South African sectors, people tend to work on many more than two or three projects simultaneously. In this paper, factors that influence the number of projects a person can work on are identified so that they can be investigated in further studies. Some ideas about using key resources optimally are also presented.Die aantal projekte wat ’n persoon gelyktydig kan hanteer is relevant in strategiese beplanning en in projek portefeuljebestuur. Internasionaal is die de facto standaard blykbaar dat mens nie gelyktydig op meer as twee of drie projekte behoort te werk nie; maar daar is verskeie faktore wat hierdie syfer kan beïnvloed. Empiriese data vanuit sommige Suid-Afrikaanse sektore toon dat mense tipies gelyktydig op veel meer as twee of drie projekte werk. In hierdie artikel is faktore wat die aantal projekte waarop ’n persoon gelyktydig kan werk geïdentifiseer, sodat dit in verdere studies ondersoek kan word. Idees vir die optimale aanwending van sleutelhulpbronne word ook voorgestel.http://sajie.journals.ac.za/pubhb201

CONCURRENT PROJECTS: HOW MANY CAN YOU HANDLE?

The number of projects a person can handle simultaneously is a relevant factor in strategic planning and in project portfolio management. Internationally the de facto standard seems to be that a person should not work on more than two or three projects simultaneously; but several factors could influence this figure. Empirical evidence indicates that, in some South African sectors, people tend to work on many more than two or three projects simultaneously. In this paper, factors that influence the number of projects a person can work on are identified so that they can be investigated in further studies. Some ideas about using key resources optimally are also presented.Die aantal projekte wat ’n persoon gelyktydig kan hanteer is relevant in strategiese beplanning en in projek portefeuljebestuur. Internasionaal is die de facto standaard blykbaar dat mens nie gelyktydig op meer as twee of drie projekte behoort te werk nie; maar daar is verskeie faktore wat hierdie syfer kan beïnvloed. Empiriese data vanuit sommige Suid-Afrikaanse sektore toon dat mense tipies gelyktydig op veel meer as twee of drie projekte werk. In hierdie artikel is faktore wat die aantal projekte waarop ’n persoon gelyktydig kan werk geïdentifiseer, sodat dit in verdere studies ondersoek kan word. Idees vir die optimale aanwending van sleutelhulpbronne word ook voorgestel.http://sajie.journals.ac.za/pubhb201

CHARACTERISTICS OF MATRIX STRUCTURES, AND THEIR EFFECTS ON PROJECT SUCCESS

This paper investigates the characteristics of matrix structures and their relationships with drivers of project success, such as communication, collaboration, and trust between project team members. Matrix characteristics that were expected to correlate positively with project success mostly did correlate with the success drivers. However, characteristics expected to impact negatively on project success did not show such significant correlations; some even correlated positively with success drivers. The success drivers investigated, in turn, correlated positively with perceived project success. A proposed model illustrates the effects of matrix characteristics on the drivers of success and their ultimate effect on project performance.Eienskappe van matriks strukture en hul effek op drywers van projeksukses – naamlik kommunikasie, samewerking, en vertroue tussen projek-spanlede – is ondersoek. Eienskappe wat verwag was om positief met projeksukses te korreleer het meestal wel positief gekorreleer met die drywers van sukses. Eienskappe wat verwag was om negatief met projeksukses te korreleer het egter nie sulke beduidende korrelasies getoon nie; sommige het selfs positief gekorreleer met projeksukses. Drywers van sukses het ook positief gekorreleer met waargenome projeksukses. ’n Voorgestelde model illustreer die verwantskappe tussen matriks-eienskappe op kommunikasie, samewerking, en vertroue tussen spanlede, en die uit eindelike effek op projekprestasie.http://sajie.journals.ac.za/pubam201

Lipid composition of human meibum

The structure and function of meibomian gland lipids in the tear film are highly complex. Evidence shows that the precorneal tear film consists of discrete layers: the inner mucin layer, the middle aqueous layer and the outer lipid layer. In this review we focus on the outer, biphasic lipid layer of the tear film which consists of a ‘thick’ outer, non-polar layer  and a ‘thin’ inner, polar layer. We discuss the main composition of the polar and non-polar lipids within meibum (wax esters, cholesteryl esters, mono-, di- and tri-acylglycerols, ceramides, phospholipids  et cetera). We address the composition of meibomian lipids in subjects suffering from various ocular diseases in comparison with the composition in healthy individuals. Further analysis is needed to determine whether a correlation exists between the etiology of various ocular diseases and the fluctuation on the lipids as well as to establish whether or not tear lipid analysis can be used as a diagnostic tool

Characteristics of matrix structures, and their effects on project success

This paper investigates the characteristics of matrix structures and their relationships with drivers of project success, such as communication, collaboration, and trust between project team members. Matrix characteristics that were expected to correlate positively with project success mostly did correlate with the success drivers. However, characteristics expected to impact negatively on project success did not show such significant correlations; some even correlated positively with success drivers. The success drivers investigated, in turn, correlated positively with perceived project success. A proposed model illustrates the effects of matrix characteristics on the drivers of success and their ultimate effect on project performance.Eienskappe van matriks strukture en hul effek op drywers van projeksukses – naamlik kommunikasie, samewerking, en vertroue tussen projek-spanlede – is ondersoek. Eienskappe wat verwag was om positief met projeksukses te korreleer het meestal wel positief gekorreleer met die drywers van sukses. Eienskappe wat verwag was om negatief met projeksukses te korreleer het egter nie sulke beduidende korrelasies getoon nie; sommige het selfs positief gekorreleer met projeksukses. Drywers van sukses het ook positief gekorreleer met waargenome projeksukses. ’n Voorgestelde model illustreer die verwantskappe tussen matriks-eienskappe op kommunikasie, samewerking, en vertroue tussen spanlede, en die uit eindelike effek op projekprestasie.http://sajie.journals.ac.za/pubam201

EAGLE multi-object AO concept study for the E-ELT

EAGLE is the multi-object, spatially-resolved, near-IR spectrograph instrument concept for the E-ELT, relying on a distributed Adaptive Optics, so-called Multi Object Adaptive Optics. This paper presents the results of a phase A study. Using 84x84 actuator deformable mirrors, the performed analysis demonstrates that 6 laser guide stars and up to 5 natural guide stars of magnitude R<17, picked-up in a 7.3' diameter patrol field of view, allow us to obtain an overall performance in terms of Ensquared Energy of 35% in a 75x75 mas^2 spaxel at H band, whatever the target direction in the centred 5' science field for median seeing conditions. The computed sky coverage at galactic latitudes |b|~60 is close to 90%.Comment: 6 pages, to appear in the proceedings of the AO4ELT conference, held in Paris, 22-26 June 200

Oral medicine case book 71 : Amyloidosis of the tongue

A 57-year-old male patient presented to the Oral Medicine Clinic with a one-month history of painful macroglossia associated with difficulty in speaking and swallowing. The patient complained of recent weight loss and chronic fatigue. Intra-oral examination showed the tongue to be enlarged with conspicuous nodules on the lateral borders. It had a multinodular, firm consistency on palpation. An incisional biopsy from the right lateral area of the tongue was submitted for histology.http://www.sada.co.zaam201

The role of primary healthcare professionals in oral cancer prevention and detection

AIM: To investigate current knowledge, examination habits and preventive practices of primary healthcare professionals in Scotland, with respect to oral cancer, and to determine any relevant training needs. SETTING: Primary care. METHOD: Questionnaires were sent to a random sample of 357 general medical practitioners (GMPs) and 331 dental practitioners throughout Scotland. Additionally, focus group research and interviews were conducted amongst primary healthcare team members. RESULTS: Whilst 58% of dental respondents reported examining regularly for signs of oral cancer, GMPs examined patients' mouths usually in response to a complaint of soreness. The majority of GMPs (85%) and dentists (63%) indicated that they felt less than confident in detecting oral cancer, with over 70% of GMPs identifying lack of training as an important barrier. Many practitioners were unclear concerning the relative importance of the presence of potentially malignant lesions in the oral cavity. A high proportion of the GMPs indicated that they should have a major role to play in oral cancer detection (66%) but many felt strongly that this should be primarily the remit of the dental team. CONCLUSION: The study revealed a need for continuing education programmes for primary care practitioners in oral cancer-related activities. This should aim to improve diagnostic skills and seek to increase practitioners' participation in preventive activities