Quality of Service over Specific Link Layers: state of the art report

The Integrated Services concept is proposed as an enhancement to the current Internet architecture, to provide a better Quality of Service (QoS) than that provided by the traditional Best-Effort service. The features of the Integrated Services are explained in this report. To support Integrated Services, certain requirements are posed on the underlying link layer. These requirements are studied by the Integrated Services over Specific Link Layers (ISSLL) IETF working group. The status of this ongoing research is reported in this document. To be more specific, the solutions to provide Integrated Services over ATM, IEEE 802 LAN technologies and low-bitrate links are evaluated in detail. The ISSLL working group has not yet studied the requirements, that are posed on the underlying link layer, when this link layer is wireless. Therefore, this state of the art report is extended with an identification of the requirements that are posed on the underlying wireless link, to provide differentiated Quality of Service

Quality of Service in Bluetooth networking - part I

The Quality of Service functions and procedures included in the Bluetooth 1.0 specification have been reviewed. Next issues associated with providing Quality of Service over a wireless link in general and Bluetooth in particular have been investigated. Allthough the Bluetooth 1.0 specification provides some Quality of Service support, some deficiencies have been identified. The requirements for QoS enhancements to the Bluetooth 1.0 specification and a Quality of Service Framework are presented in this document. The document is concluded with issues for future work

Dynamics of Starbursting Dwarf Galaxies: I Zw 18

I Zw 18 is a prototype Blue Compact Dwarf (BCD), characterized by a strong starburst and extremely low metallicity (Z ~ 0.02 Zsun). It has long been considered a candidate young galaxy in the Local Universe, but recent studies indicate the presence of old stars. We analysed archival VLA observations of the 21 cm line and found that the HI associated to the starburst region forms a compact fast-rotating disk. The HI column densities are very high, up to ~50-100 Msun/pc^2 (~0.6-1.2 x 10^22 atoms/cm^2). The rotation curve is flat with a steep rise in the inner parts, indicating the presence of a strong central concentration of mass. Mass models with a dark matter halo show that baryons may dominate the gravitational potential in the inner regions. A radial inflow/outflow motion of ~15 km/s is also present. I Zw 18 appears structurally different from typical dwarf irregulars in terms of gas distribution, stellar distribution and dynamics. It may be considered as a "miniature" high-surface-brightness disk galaxy. These dynamical properties must be tightly related to the starburst. They also shed new light on the question of the descendants of BCDs. There is also extended HI emission towards the outlying stellar complex I Zw 18 C and a ~13.5 kpc HI tail. An interaction/merger between gas-rich dwarfs is the most likely explanation for the starburst.Comment: 13 pages, 10 figures, to be published in Astronomy & Astrophysic

Expectations Regarding Gastein Healing Gallery Treatment and Their Connection to Health-Related Quality of Life

The present study examines connections between patient expectations and health-related quality of life. We explore a key distinction between expectations about general health and expectations for functional improvement. Patients were 1444 individuals with multiple conditions experiencing chronic pain who were seeking treatment at the Gastein Healing Gallery in Böckstein, near Bad Gastein, Austria. In addition to measures of expectations, patients completed measures of pain, mental and physical health, life satisfaction, fatigue, and sleep problems. Structural equation models were used to fit a latent variable model where both expectation variables were used to predict health-related quality of life. Results showed that expectations regarding potential functional improvement resulting from treatments at the Gastein Healing Gallery were associated with improved health-related quality of life. Expectations about general health improvements related to treatment were not associated with health-related quality of life. To facilitate optimal healing, clinicians may decide to emphasize expectations about functional recovery when discussing treatment methods similar to those offered at the Gastein Healing Gallery, and in so doing, health-related quality of life may benefit

Facile Synthesis of Tuneable Azophosphonium Salts

Azophosphonium salts have a facile synthesis and can be readily tuned at the para position of the aryl group and at the phosphorus position with the use of bulky phosphines, leading to a range of coloured compounds. A relation between the Hammett sigma(+)(para) constant and the colour and P-31 NMR chemical shift was explored. The compounds were characterised by NMR spectroscopy, UV/Vis spectroscopy and single-crystal X-ray structure crystallography.Peer reviewe

The Westerbork HI Survey of spiral and irregular galaxies III: HI observations of early-type disk galaxies

We present HI observations of 68 early-type disk galaxies from the WHISP survey. They have morphological types between S0 and Sab and absolute B-band magnitudes between -14 and -22. These galaxies form the massive, high surface-brightness extreme of the disk galaxy population, few of which have been imaged in HI before. The HI properties of the galaxies in our sample span a large range; the average values of M_HI/L_B and D_HI/D_25 are comparable to the ones found in later-type spirals, but the dispersions around the mean are larger. No significant differences are found between the S0/S0a and the Sa/Sab galaxies. Our early-type disk galaxies follow the same HI mass-diameter relation as later-type spiral galaxies, but their effective HI surface densities are slightly lower than those found in later-type systems. In some galaxies, distinct rings of HI emission coincide with regions of enhanced star formation, even though the average gas densities are far below the threshold of star formation derived by Kennicutt (1989). Apparently, additional mechanisms, as yet unknown, regulate star formation at low surface densities. Many of the galaxies in our sample have lopsided gas morphologies; in most cases this can be linked to recent or ongoing interactions or merger events. Asymmetries are rare in quiescent galaxies. Kinematic lopsidedness is rare, both in interacting and isolated systems. In the appendix, we present an atlas of the HI observations: for all galaxies we show HI surface density maps, global profiles, velocity fields and radial surface density profiles.Comment: 24 pages, 11 figures. Accepted for publication in A&A. A version with the full atlas can be downloaded from http://www.astro.rug.nl/~edo/WHISPIII.ps.gz (gzipped postscript, 9.3Mb

Mutated CTSF in adult-onset neuronal ceroid lipofuscinosis and FTD

OBJECTIVE: To investigate the molecular basis of a Belgian family with autosomal recessive adult-onset neuronal ceroid lipofuscinosis (ANCL or Kufs disease [KD]) with pronounced frontal lobe involvement and to expand the findings to a cohort of unrelated Belgian patients with frontotemporal dementia (FTD). METHODS: Genetic screening in the ANCL family and FTD cohort (n = 461) was performed using exome sequencing and targeted massive parallel resequencing. RESULTS: We identified a homozygous mutation (p.Ile404Thr) in the Cathepsin F (CTSF) gene cosegregating in the ANCL family. No other mutations were found that could explain the disease in this family. All 4 affected sibs developed motor symptoms and early-onset dementia with prominent frontal features. Two of them evolved to akinetic mutism. Disease presentation showed marked phenotypic variation with the onset ranging from 26 to 50 years. Myoclonic epilepsy in one of the sibs was suggestive for KD type A, while epilepsy was not present in the other sibs who presented with clinical features of KD type B. In a Belgian cohort of unrelated patients with FTD, the same heterozygous p.Arg245His mutation was identified in 2 patients who shared a common haplotype. CONCLUSIONS: A homozygous CTSF mutation was identified in a recessive ANCL pedigree. In contrast to the previous associations of CTSF with KD type B, our findings suggest that CTSF genetic testing should also be considered in patients with KD type A as well as in early-onset dementia with prominent frontal lobe and motor symptoms

On the Nature of Star Formation at Large Galactic Radii

We have compared far-ultraviolet (FUV), near-ultraviolet (NUV), and Halpha measurements for star forming regions in 21 galaxies, in order to characterise the properties of their discs at radii beyond the main optical radius (R25). In our representative sample of extended and non-extended UV discs we find that half of the extended UV discs also exhibit extended Halpha emission. We find that extended UV discs fall into two categories, those with a sharp truncation in the Halpha disc close to the optical edge (R25), and those with extended emission in Halpha as well as in the ultraviolet. Although most galaxies with strong Halpha truncations near R25 show a significant corresponding falloff in UV emission (factor 10--100), the transition tends to be much smoother than in Halpha, and significant UV emission often extends well beyond this radius, confirming earlier results by Thilker et al. (2007) and others. After correcting for dust attenuation the median fraction of total FUV emission from regions outside of R25 is 1.7%, but it can be as high as 35% in the most extreme cases. The corresponding fractions of Halpha emission are approximately half as large on average. This difference reflects both a slightly lower ratio of Halpha to UV emission in the HII regions in the outer discs, as well as a lower fraction of star clusters showing HII regions. Most HII regions in the extended disc have fluxes consistent with small numbers of ionising O-type stars, and this poor sampling of the upper initial mass function in small clusters can probably account for the differences in the emission properties, consistent with earlier conclusions by Zaritsky & Christlein (2007), without needing to invoke a significant change in the stellar IMF itself. Consistent Ha/FUV ratios and brightest HII region to total Halpha fluxes in the inner and extended discs across our whole galaxy sample demonstrate no evidence for a change in the cluster luminosity function or the IMF in the low gas density outer disc.Comment: Accepted for publication in MNRAS. 21 Pages, 13 Figures, 2 Table