132 research outputs found
Hybrid Command Issuing in a 2-Dof Servomechanism Operated Under Vision-Based Feedback Control
This paper presents a new method for generating motion commands in a 2 degree-of-freedom (DOF) vision-based position control system. The control system uses a fixed digital camera to direct-observe the multi-dimensional position of a known target displayed on an Liquid Cristal Display (LCD) and determines the position of the tool based on this information. This system, implemented on an XY-stage, was first introduced in Wong [1], and further investigated in Montes & Ziegert [2] and Montes et al. [3]. Previous results demonstrated sensor resolutions on the order of 3 Āµm; however the resolution of motion commands was constrained to values on the order of hundreds of microns due to the physical characteristics of the LCD picture elements (or pixels). The new method presented here overcomes this constraint and allows generation of motion commands as small as 3 Āµm. Simulation results are provided
Dynamic Delegation: Shared, Hierarchical, and Deindividualized Leadership in Extreme Action Teams
This paper examines the leadership of extreme action teamsāteams whose highly skilled members cooperate to perform urgent, unpredictable, interdependent, and highly consequential tasks while simultaneously coping with frequent changes in team composition and training their teams\u27 novice members. Our qualitative investigation of the leadership of extreme action medical teams in an emergency trauma center revealed a hierarchical, deindividualized system of shared leadership. At the heart of this system is dynamic delegation: senior leaders\u27 rapid and repeated delegation of the active leadership role to and withdrawal of the active leadership role from more junior leaders of the team. Our findings suggest that dynamic delegation enhances extreme action teams\u27 ability to perform reliably while also building their novice team members\u27 skills. We highlight the contingencies that guide senior leaders\u27 delegation and withdrawal of the active leadership role, as well as the values and structures that motivate and enable the shared, ongoing practice of dynamic delegation. Further, we suggest that extreme action teams and other āimprovisationalā organizational units may achieve swift coordination and reliable performance by melding hierarchical and bureaucratic role-based structures with flexibility-enhancing processes. The insights emerging from our findings at once extend and challenge prior leadership theory and research, paving the way for further theory development and research on team leadership in dynamic settings
Maintaining families' well-being in everyday life
The aim of this paper is to discuss how everyday life changes for the family in the event of chronic illness or disability. It changes physically due to loss of body function and socially due to time and other constraints related to treatment or lack of mobility. Equally important, there is a psychological impact due to the uncertainty of the future. The article will explore how family participation can help to maintain well-being in everyday life. The family should therefore focus on their own needs as much as on the needs of the family members who are ill. In order to maintain well-being in everyday life, it is crucial for the family to create routines and spend time doing things that they enjoy. By doing this, the family will create a rhythm of well-being regardless of the critical family situation. Family members and professional caregivers also need to come together at the beginning and during the illness or disability event to discuss changes that could be made day-to-day for all those involved, thereby making for an easier transition into care giving
Direct Neutron Capture for Magic-Shell Nuclei
In neutron capture for magic--shell nuclei the direct reaction mechanism can
be important and may even dominate. As an example we investigated the reaction
Ca(n,Ca for projectile energies below 250\,keV in a direct
capture model using the folding procedure for optical and bound state
potentials. The obtained theoretical cross sections are in agreement with the
experimental data showing the dominance of the direct reaction mechanism in
this case. The above method was also used to calculate the cross section for
Ca(n,Ca.Comment: REVTeX, 7 pages plus 3 uuencoded figures, the complete uuencoded
postscript file is available at ftp://is1.kph.tuwien.ac.at/pub/ohu/calcium.u
Measurement of neutron capture on Ca at thermal and thermonuclear energies
At the Karlsruhe pulsed 3.75\,MV Van de Graaff accelerator the thermonuclear
Ca(n,)Ca(8.72\,min) cross section was measured by the
fast cyclic activation technique via the 3084.5\,keV -ray line of the
Ca-decay. Samples of CaCO enriched in Ca by 77.87\,\% were
irradiated between two gold foils which served as capture standards. The
capture cross-section was measured at the neutron energies 25, 151, 176, and
218\,keV, respectively. Additionally, the thermal capture cross-section was
measured at the reactor BR1 in Mol, Belgium, via the prompt and decay
-ray lines using the same target material. The
Ca(n,)Ca cross-section in the thermonuclear and thermal
energy range has been calculated using the direct-capture model combined with
folding potentials. The potential strengths are adjusted to the scattering
length and the binding energies of the final states in Ca. The small
coherent elastic cross section of Ca+n is explained through the nuclear
Ramsauer effect. Spectroscopic factors of Ca have been extracted from
the thermal capture cross-section with better accuracy than from a recent (d,p)
experiment. Within the uncertainties both results are in agreement. The
non-resonant thermal and thermonuclear experimental data for this reaction can
be reproduced using the direct-capture model. A possible interference with a
resonant contribution is discussed. The neutron spectroscopic factors of
Ca determined from shell-model calculations are compared with the values
extracted from the experimental cross sections for Ca(d,p)Ca and
Ca(n,)Ca.Comment: 15 pages (uses Revtex), 7 postscript figures (uses psfig), accepted
for publication in PRC, uuencoded tex-files and postscript-files also
available at ftp://is1.kph.tuwien.ac.at/pub/ohu/Ca.u
Dealing with daily emotionsāsupportive activities for the elderly in a municipal care setting
There are diverse descriptions of supportive activities in nursing to be found in the literature. What they have in common is their association with good care outcomes, but they may differ depending on the context in which the care is given. In a Swedish municipal elderly care setting, registered nurses (RN) work in a consultative way and they describe a part of their tasks as comprising supportive activities without specifying what kind of supportive activities they mean. The aim of the study was to explore the main concern of the support given by RN to a group of patients in an elderly home care setting. The study was conducted using Grounded Theory. Data were collected using nonparticipant observations regarding the supportive activities of 12 RN at the home of 36 patients between the ages of 80 and 102. Most of the home visit lasted about 40 min but some lasted for 90 min. The central category was about dealing with daily emotions. This was done by encouraging the situation and reducing the patient's limitations, but situations also occurred in which there was a gap of support. Support was about capturing the emotions that the patient expressed for a particular moment, but there were also situations in which RN chose not to give support. To develop a holistic eldercare, more knowledge is needed about the factors causing the RN to choose not to provide support on some occasions
Influence of wheel size on muscle activity and tri-axial accelerations during cross-country mountain biking
The origins and development of Zuwīla, Libyan Sahara: an archaeological and historical overview of an ancient oasis town and caravan centre
ZuwÄ«la in southwestern Libya (FazzÄn) was one of the most important early Islamic centres in the Central Sahara, but the archaeological correlates of the written sources for it have been little explored. This paper brings together for the first time a detailed consideration of the relevant historical and archaeological data, together with new AMS radiocarbon dates from several key monuments. The origins of the settlement at ZuwÄ«la were pre-Islamic, but the town gained greater prominence in the early centuries of Arab rule of the Maghrib, culminating with the establishment of an IbÄįøÄ« state ruled by the dynasty of the BanÅ« Khaį¹į¹Äb, with ZuwÄ«la its capital. The historical sources and the accounts of early European travellers are discussed and archaeological work at ZuwÄ«la is described (including the new radiocarbon dates). A short gazetteer of archaeological monuments is provided as an appendix. Comparisons and contrasts are also drawn between ZuwÄ«la and other oases of the ash-SharqiyÄt region of FazzÄn. The final section of the paper presents a series of models based on the available evidence, tracing the evolution and decline of this remarkable site
Empowerment in outpatient care for patients with chronic kidney disease - from the family member's perspective
The 3' region of Human Papillomavirus type 16 early mRNAs decrease expression
BACKGROUND: High risk human papillomavirus (HR-HPV) infects mucosal surfaces and HR-HPV infection is required for development of cervical cancer. Accordingly, enforced expression of the early HR-HPV proteins can induce immortalisation of human cells. In most cervical cancers and cervical cancer cell lines the HR-HPV double stranded DNA genome has been integrated into the host cell genome. METHODS: We have used a retroviral GUS reporter system to generate pools of stably transfected HaCaT and SiHa cells. The HPV-16 early sequences that are deleted upon integration of the HPV-16 genome was inserted into the 3' UTR of the reporter mRNA. Pools containing thousands of independent integrations were tested for the steady state levels of the reporter mRNA by Real Time PCR and reporter protein by a GUS enzymatic activity assays. In addition, we tested the cellular distribution and half lives of the reporter mRNAs. The integrity of the reporter mRNAs were tested by northern blotting. RESULTS: We show that the 3' region of the HPV-16 early mRNAs (HPV-16 nucleotide (nt.) 2582ā4214) act in cis to decrease both mRNA and protein levels. This region seems to affect transcription from the exogenous minimal CMV promoter or processing of the reporter mRNA. The observed repression was most pronounced at the protein level, suggesting that this sequence may also affect translation. For the HPV types: 2, 6, 11, 13, 18, 30, 31, and 35 we have investigated the regulatory effect of the regions corresponding to the HPV-16 nt. 3358ā4214. For all types, except HPV-18, the region was found to repress expression by posttranscriptional mechanisms. CONCLUSION: We find that the 3' region of HPV-16 early mRNAs interfere with gene expression. It is therefore possible that the deletion of the 3' part of early HPV-16 mRNAs occurring during cervical oncogenesis could contribute to transformation of cells through deregulation of the viral oncogene synthesis. Moreover, we find that the corresponding region from several other HPV types also repress expression, suggesting that the repression by this region may be a general feature of the HPV life cycle
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