The beta-transformation with a hole at 0

Analysis and Stochastic

Dopant-induced crossover from 1D to 3D charge transport in conjugated polymers

The interplay between inter- and intra-chain charge transport in bulk polythiophene in the hopping regime has been clarified by studying the conductivity as a function of frequency (up to 3 THz), temperature and doping level. We present a model which quantitatively explains the observed crossover from quasi-one-dimensional transport to three-dimensional hopping conduction with increasing doping level. At high frequencies the conductivity is dominated by charge transport on one-dimensional conducting chains.Comment: 4 pages, 2 figure

Injecteerbare transponders

Uit de resultaten van de veldtest met injecteerbare transponders op proefbedrijven blijkt dat er nog problemen bestaan ten aanzien van verlies van transponders (technisch defect en/of verdwijnen uit het dier), optreden van infecties en nauwkeurigheid van injecteren van transponders

Search for Millicharged Particles at SLAC

Particles with electric charge q < 10^(-3)e and masses in the range 1--100 MeV/c^2 are not excluded by present experiments. An experiment uniquely suited to the production and detection of such "millicharged" particles has been carried out at SLAC. This experiment is sensitive to the infrequent excitation and ionization of matter expected from the passage of such a particle. Analysis of the data rules out a region of mass and charge, establishing, for example, a 95%-confidence upper limit on electric charge of 4.1X10^(-5)e for millicharged particles of mass 1 MeV/c^2 and 5.8X10^(-4)e for mass 100 MeV/c^2.Comment: 4 pages, REVTeX, multicol, 3 figures. Minor typo corrected. Submitted to Physical Review Letter

Prognostic Factors for Long-term Aesthetic Outcome of Infantile Haemangioma Treated with Beta-blockers

Parents of infants treated with beta-blockers for infantile haemangioma are often concerned about the long-term aesthetic outcome. This cross-sectional study assessed the influence on the long-term aesthetic outcome of characteristics of the infantile haemangioma, the beta-blocker treatment, and the infant. The study included 103 children aged 6-12 years, treated with beta-blockers (propranolol or atenolol) for infantile haemangioma during infancy (age at treatment initiation ≤1 year) for ≥6 months. Dermatologists and parents scored the Patient Observer Scar Assessment Scale, and the child scored a visual analogue scale. Dermatologists identified whether telangiectasia, fibrofatty tissue, and atrophic scar tissue were present. The long-term aesthetic outcome of infantile haemangioma was judged more negatively by dermatologists and parents in case of a superficial component, ulceration, older age at treatment initiation, higher cumulative dose, and/or shorter follow-up time. According to children, infantile haemangioma located on the head had better aesthetic outcome than infantile haemangioma located elsewhere. Close monitoring, particularly of infantile haemangioma with a superficial component, is essential for early initiation of treatment, and to prevent or treat ulceration. These outcome data can support parental counselling and guide treatment strategy.</p

Clinical factors associated with fatigue over time in paediatric oncology patients receiving chemotherapy

The purpose of this study was to investigate the relationships between clinical factors (including haemoglobin value, chemotherapeutic agents, and corticosteroid use) and changing patterns of fatigue before and for the next 10 days following the start of a new round of chemotherapy in children with cancer. A prospective longitudinal design was used to collect data from 48 paediatric oncology patients who were about to begin a new round of chemotherapy and their parents. Fatigue levels were assessed using multidomain questionnaires with three categories of patient self-report (including ‘General Fatigue', ‘Sleep/Rest Fatigue', and ‘Cognitive Fatigue') and four categories of parent proxy-report (including ‘Lack of Energy', ‘Unable to Function', ‘Altered Sleep', and ‘Altered Mood'). The findings suggest that fatigue from both patient self-report and parent proxy-report changed significantly over time. The major findings from this study are that patients have more problems with fatigue in the first few days after the start of a cycle of chemotherapy. Corticosteroid use and haemoglobin value were associated with significant increases in fatigue that were sustained for several days and reached the highest level of fatigue at day 5 for those receiving concurrent steroids. The association of chemotherapeutic agents with fatigue varied between patient self-report and parent report, but the type of chemotherapeutic agents used was not associated with most changes in fatigue

LKB1 as the ghostwriter of crypt history

Familial cancer syndromes present rare insights into malignant tumor development. The molecular background of polyp formation and the cancer prone state in Peutz-Jeghers syndrome remain enigmatic to this day. Previously, we proposed that Peutz-Jeghers polyps are not pre-malignant lesions, but an epiphenomenon to the malignant condition. However, Peutz-Jeghers polyp formation and the cancer-prone state must both be accounted for by the same molecular mechanism. Our contribution focuses on the histopathology of the characteristic Peutz-Jeghers polyp and recent research on stem cell dynamics and how these concepts relate to Peutz-Jeghers polyposis. We discuss a protracted clonal evolution scenario in Peutz-Jeghers syndrome due to a germline LKB1 mutation. Peutz-Jeghers polyp formation and malignant transformation are separately mediated through the same molecular mechanism played out on different timescales. Thus, a single mechanism accounts for the development of benign Peutz-Jeghers polyps and for malignant transformation in Peutz-Jeghers syndrome