The MS Symptom and Impact Diary (MSSID): psychometric evaluation of a new instrument to measure the day to day impact of multiple sclerosis

OBJECTIVES: This study aimed to develop further a diary originally devised to measure the impact of multiple sclerosis (MS) as part of a cost utility study of beta interferon, and to evaluate its reliability, validity, and responsiveness in an outpatient sample of people with MS. METHODS: The original diary was further developed using qualitative and quantitative methods to ensure that it addressed the views of people with MS. The psychometric properties of the MS Symptom and Impact Diary (MSSID) were evaluated in a sample of 77 people who completed the MSSID daily for 12 weeks. Internal and test–retest reliability, discriminant and convergent validity, and responsiveness were assessed using traditional psychometric methods. RESULTS: The MSSID formed three, internally consistent scales that measured mobility, fatigue, and the overall impact of MS. The test–retest reliability of the mobility scale was adequate for individual comparisons (ICC.0.90) and the fatigue and overall impact scales were adequate for group comparisons (ICC.0.70). The MSSID was able to distinguish between clinical groups depending on clinical course, indoor ambulation status, and relapse status. It demonstrated associations with other single point instruments in the expected direction. Compared with single point instruments, its responsiveness was similar or better, especially in detecting short term improvements in functioning. CONCLUSIONS: The MSSID may provide a useful complement to currently available instruments to measure the outcomes of MS within clinical trials. Further research is needed to explore its feasibility in the context of a randomised controlled trial and its utility for clinicians

The 6-vertex model of hydrogen-bonded crystals with bond defects

It is shown that the percolation model of hydrogen-bonded crystals, which is a 6-vertex model with bond defects, is completely equivalent with an 8-vertex model in an external electric field. Using this equivalence we solve exactly a particular 6-vertex model with bond defects. The general solution for the Bethe-like lattice is also analyzed.Comment: 13 pages, 6 figures; added references for section

Cellular automaton rules conserving the number of active sites

This paper shows how to determine all the unidimensional two-state cellular automaton rules of a given number of inputs which conserve the number of active sites. These rules have to satisfy a necessary and sufficient condition. If the active sites are viewed as cells occupied by identical particles, these cellular automaton rules represent evolution operators of systems of identical interacting particles whose total number is conserved. Some of these rules, which allow motion in both directions, mimic ensembles of one-dimensional pseudo-random walkers. Numerical evidence indicates that the corresponding stochastic processes might be non-Gaussian.Comment: 14 pages, 5 figure

‘At least you got to see people when you went out for a walk’: older adults’ lived, embodied experiences during COVID-19 times in the United Kingdom

The COVID-19 pandemic presented myriad global challenges, placing unprecedented pressure on health services. Currently, there is limited qualitative research exploring the ‘felt’ impact of the pandemic on older adults’ health experiences and wider social life. Here, we report on the embodied experiences of older adults (65 and above), before, during and after the COVID-19 pandemic lockdowns in the UK, to chart the physical, social, and mental-health challenges. A figurational sociological lens was adopted to examine data from semi-structured interviews with 18 older adults, face-to-face or via telephone/video call. Notes from follow-up conversations were also recorded. Combined data were analysed thematically. Salient themes cohered around: physical activity engagement; health experiences; the role of family, friends, and community; and the role of modern technology. Our results highlight how older adults reported the felt benefits of increased PA during lockdowns, but also the negative impacts of treatment delays on experiences of hospital services. Participants also recounted how new social community connections were forged during lockdowns. Saliently, we identified a need to support older adults with modern technology so as to capture its potential to modernise, expand, and personalise healthcare within UK health services

A laser gyroscope system to detect the Gravito-Magnetic effect on Earth

Large scale square ring laser gyros with a length of four meters on each side are approaching a sensitivity of 1x10^-11 rad/s/sqrt(Hz). This is about the regime required to measure the gravitomagnetic effect (Lense Thirring) of the Earth. For an ensemble of linearly independent gyros each measurement signal depends upon the orientation of each single axis gyro with respect to the rotational axis of the Earth. Therefore at least 3 gyros are necessary to reconstruct the complete angular orientation of the apparatus. In general, the setup consists of several laser gyroscopes (we would prefer more than 3 for sufficient redundancy), rigidly referenced to each other. Adding more gyros for one plane of observation provides a cross-check against intra-system biases and furthermore has the advantage of improving the signal to noise ratio by the square root of the number of gyros. In this paper we analyze a system of two pairs of identical gyros (twins) with a slightly different orientation with respect to the Earth axis. The twin gyro configuration has several interesting properties. The relative angle can be controlled and provides a useful null measurement. A quadruple twin system could reach a 1% sensitivity after 3:2 years of data, provided each square ring has 6 m length on a side, the system is shot noise limited and there is no source for 1/f- noise.Comment: 9 pages, 6 figures. 2010 Honourable mention of the Gravity Research Foundation; to be published on J. Mod. Phys.

Considering long-memory when testing for changepoints in surface temperature:a classification approach based on the time-varying spectrum

Changepoint models are increasingly used to represent changes in the rate of warming in surface temperature records. On the opposite hand, a large body of literature has suggested long‐memory processes to characterize long‐term behavior in surface temperatures. While these two model representations provide different insights into the underlying mechanisms, they share similar spectrum properties that create “ambiguity” and challenge distinguishing between the two classes of models. This study aims to compare the two representations to explain temporal changes and variability in surface temperatures. To address this question, we extend a recently developed time‐varying spectral procedure and assess its accuracy through a synthetic series mimicking observed global monthly surface temperatures. We vary the length of the synthetic series to determine the number of observations needed to be able to accurately distinguish between changepoints and long‐memory models. We apply the approach to two gridded surface temperature data sets. Our findings unveil regions in the oceans where long‐memory is prevalent. These results imply that the presence of long‐memory in monthly sea surface temperatures may impact the significance of trends, and special attention should be given to the choice of model representing memory (short versus long) when assessing long‐term changes

Generalized (m,k)-Zipf law for fractional Brownian motion-like time series with or without effect of an additional linear trend

We have translated fractional Brownian motion (FBM) signals into a text based on two ''letters'', as if the signal fluctuations correspond to a constant stepsize random walk. We have applied the Zipf method to extract the $\zeta '$ exponent relating the word frequency and its rank on a log-log plot. We have studied the variation of the Zipf exponent(s) giving the relationship between the frequency of occurrence of words of length $m<8$ made of such two letters: $\zeta '$ is varying as a power law in terms of $m$. We have also searched how the $\zeta '$ exponent of the Zipf law is influenced by a linear trend and the resulting effect of its slope. We can distinguish finite size effects, and results depending whether the starting FBM is persistent or not, i.e. depending on the FBM Hurst exponent $H$. It seems then numerically proven that the Zipf exponent of a persistent signal is more influenced by the trend than that of an antipersistent signal. It appears that the conjectured law $\zeta ' = |2H-1|$ only holds near $H=0.5$. We have also introduced considerations based on the notion of a {\it time dependent Zipf law} along the signal.Comment: 24 pages, 12 figures; to appear in Int. J. Modern Phys

Effect of friction on disoriented chiral condensate formation

We have investigated the effect of friction on the DCC domain formation. We solve the Newton equation of motion for the O(4) fields, with quenched initial condition. The initial fields are randomly distributed in a Gaussian form. In one dimensional expansion, on the average, large DCC domains can not be formed. However, in some particular orbits, large instabilities may occur. This possibility also greatly diminishes with the introduction of friction. But, if the friction is large, the system may be overdamped and then, there is a possibility of large DCC domain formation in some events.Comment: 9 pages, including figure

γδβ-thalassaemias 1 and 2 are the result of a 100 kpb deletion in the human β-globin cluster.

The DNA spanning two large deletions in the human beta-globin gene cluster (gamma beta-thalassaemia 1 and 2) has been cloned by cosmid cloning and chromosomal walking. The entire region was mapped and analyzed for the presence of repetitive sequences. The results show that the affected loci have lost almost 100 kb of DNA in a deletion event not involving homologous or repetitive sequences

Development of new host-specific Bacteroides qPCRs for the identification of fecal contamination sources in water

Bacteroides spp. have been proposed as indicators of fecal contamination in microbial source tracking (MST) methodologies. The aim of this study was to develop new qPCR assays that target host-specific Bacteroidal 16S ribosomal RNA genes, to determine the source of fecal contamination in water. Denaturing gradient gel electrophoresis (DGGE) was used to select for host-specific bands of Bacteroides associated with a fecal pollution source and later to design four qPCR host-specific assays. A set of common primers for Bacteroides spp., four different Bacteroides spp. host-associated hydrolysis probes (human, cattle, pig, and poultry), and one hydrolysis probe for the Bacteroides genus were designed. This set of qPCR assays together with other previously developed Bacteroidetes MST targets were used to analyze water samples with fecal contamination from the four sources studied. The host-specific Bacteroides qPCRs designed for human (HMprobeBac), pig (PGprobeBac), and poultry (PLprobeBac) were highly specific for its sources (1.0, 0.97, and 1.0, respectively) although its sensitivity was lower (0.45, 0.50, and 0.73, respectively). The cattle-specific qPCR was totally unspecific and was discarded for future experiments. When compared to previously designed assays, the human and pig qPCRs showed better accuracies (0.86 and 0.84) than their counterparts HF183 and Pig-2-Bac (0.38 and 0.65). Thus, the newly designed human, pig, and poultry qPCR assays outperform other methods developed until date and may be useful for source tracking purpose