Century scale persistence in longitude distribution: in the Sun and in silico

Using Greenwich sunspot data for 120 years it was recently observed that activity regions on the Sun's surface tend to lie along smoothly changing longitude strips 180 degrees apart from each other. However, numerical experiments with random input data show that most, if not all, of the observed longitude discrimination can be looked upon as an artifact of the analysis method.Comment: 4 pages, 12 figures, accepted for publication in Astronomy and Astrophysic

Marginal cost-based pricing of distribution: a case study

This paper presents results of a software development project carried out by the “Electricity North West” (ENW) and “TNEI” to find economic use-of-system charges for the extra high-voltage (EHV) network. Several cost-based charging models which satisfy principles set by the Regulator, such as cost reflectivity, predictability, stability and transparency were developed. In this paper, the emphasis is put on the developed software and the comparison of nodal marginal charges obtained from the proposed pricing models

A "Starless" Core that Isn't: Detection of a Source in the L1014 Dense Core with the Spitzer Space Telescope

We present observations of L1014, a dense core in the Cygnus region previously thought to be starless, but data from the Spitzer Space Telescope show the presence of an embedded source. We propose a model for this source that includes a cold core, heated by the interstellar radiation field, and a low-luminosity internal source. The low luminosity of the internal source suggests a substellar object. If L1014 is representative, other "starless" cores may turn out to harbor central sources

Predictors for being physically active to keep fit and/or to lose weight after stroke: South London stroke register

Introduction: Increased physical activity and weight loss (if appropriate) after stroke is recommended for secondary prevention in the National Clinical Guidelines for Stroke (2008). However, there is a lack information about the proportion and the characteristics of stroke patients currently undertaking physical activity to keep fit and/or lose weight. Method: Data were collected from the South London Stroke Register (SLSR), a population based stroke register covering a multiethnic source population of 271,817 inhabitants (2001) in South London. Information on stroke patients’ level of physical activity was collected 12 months post stroke. Logistic regression analysis was performed to identify independent predictors for increased physical activity to keep fit and/or lose weight post stroke, including age, sex, ethnicity, stroke severity (Barthel Index) and risk factors. Results: Between Jan 2004 and December 2006, 358 first ever stroke patients were followed up 12 months post stroke. Mean age was 69, 45% were female: ethnicity was categorized as white (65%), black (25%) and other (10%).Overall, 45% of surviving stroke patients reported undertaking exercise, 25% and 1% reported exercising to keep fit and lose weight respectively, 19% reported exercising to keep fit and lose weight. In multivariate analysis, being physically active was associated with younger age (p<0.001), less severe disability (p<0.001) and black ethnicity (p<0.005). Conclusion: This study identified only one half of stroke survivors participate in physical activity at 12 months post stroke. Stroke survivors reported being physically active for different reasons but are less likely to do so to lose weight

Exact averages of central values of triple product L-functions

We obtain exact formulas for central values of triple product L-functions averaged over newforms of weight 2 and prime level. We apply these formulas to non-vanishing problems. This paper uses a period formula for the triple product L-function proved by Gross and Kudla

Assessment of Kinematics and Electromyography Following Arthroscopic Single-Tendon Rotator Cuff Repair

Background The increasing demand for rotator cuff (RC) repair patients to return to work as soon as they are physically able has led to exploration of when this is feasible. Current guidelines from our orthopedic surgery clinic recommend a return to work at 9 weeks postoperation. To more fully define capacity to return to work, the current study was conducted using a unique series of quantitative tools. To date, no study has combined 3-dimensional (3D) motion analysis with electromyography (EMG) assessment during activities of daily living (ADLs), including desk tasks, and commonly prescribed rehabilitation exercise. Objective To apply a quantitative, validated upper extremity model to assess the kinematics and muscle activity of the shoulder following repair of the supraspinatus RC tendon compared to that in healthy shoulders. Design A prospective, cross-sectional comparison study. Setting All participants were evaluated during a single session at the Medical College of Wisconsin Department of Orthopaedic Surgery\u27s Motion Analysis Laboratory. Participants Ten participants who were 9-12 weeks post–operative repair of a supraspinatus RC tendon tear and 10 participants with healthy shoulders (HS) were evaluated. Methods All participants were evaluated with 3D motion analysis using a validated upper extremity model and synchronized EMG. Data from the 2 groups were compared using multivariate Hotelling T2 tests with post hoc analyses based on Welch t-tests. Main Outcome Measurements Participants\u27 thoracic and thoracohumeral joint kinematics, temporal-spatial parameters, and RC muscle activity were measured by applying a quantitative upper extremity model during 10 activities of daily living and 3 rehabilitation exercises. These included tasks of hair combing, drinking, writing, computer mouse use, typing, calling, reaching to back pocket, pushing a door open, pulling a door closed, external rotation, internal rotation, and rowing. Results There were significant differences of the thoracohumeral joint motion in only a few of the tested tasks: comb maximal flexion angle (P = .004), pull door internal/external rotation range of motion (P = .020), reach abduction/adduction range of motion (P = .001), reach flexion/extension range of motion (P = .001), reach extension minimal angle (P = .025), active external rotation maximal angle (P = .012), and active external rotation minimal angle (P = .004). The thorax showed significantly different kinematics of maximal flexion angle during the call (P = .011), mouse (P = .007), and drink tasks (P = .005) between the 2 groups. The EMG data analysis showed significantly increased subscapularis activity in the RC repair group during active external rotation. Conclusions Although limited abduction was expected due to repair of the supraspinatus tendon, only a single ADL (reaching to back pocket) had a significantly reduced abduction range of motion. Thoracic motion was shown to be used as a compensatory strategy during seated ADLs. Less flexion of the thorax may create passive shoulder flexion at the thoracohumeral joint in efforts to avoid active flexion. The RC repair group participants were able to accomplish the ADLs within the same time frame and through thoracohumeral joint kinematics similar to those in the healthy shoulder group participants. In summary, this study presents a quantification of the effects of RC repair and rehabilitation on the ability to perform ADLs. It may also point to a need for increased rehabilitation focus on either regaining external rotation strength or range of motion following RC repair to enhance recovery and return to the workforce

Transverse instability for non-normal parameters

We consider the behaviour of attractors near invariant subspaces on varying a parameter that does not preserve the dynamics in the invariant subspace but is otherwise generic, in a smooth dynamical system. We refer to such a parameter as ``non-normal''. If there is chaos in the invariant subspace that is not structurally stable, this has the effect of ``blurring out'' blowout bifurcations over a range of parameter values that we show can have positive measure in parameter space. Associated with such blowout bifurcations are bifurcations to attractors displaying a new type of intermittency that is phenomenologically similar to on-off intermittency, but where the intersection of the attractor by the invariant subspace is larger than a minimal attractor. The presence of distinct repelling and attracting invariant sets leads us to refer to this as ``in-out'' intermittency. Such behaviour cannot appear in systems where the transverse dynamics is a skew product over the system on the invariant subspace. We characterise in-out intermittency in terms of its structure in phase space and in terms of invariants of the dynamics obtained from a Markov model of the attractor. This model predicts a scaling of the length of laminar phases that is similar to that for on-off intermittency but which has some differences.Comment: 15 figures, submitted to Nonlinearity, the full paper available at http://www.maths.qmw.ac.uk/~eo

Spitzer Space Telescope Spectroscopy of Ices toward Low-Mass Embedded Protostars

Sensitive 5-38 μm Spitzer Space Telescope and ground-based 3-5 μm spectra of the embedded low-mass protostars B5 IRS1 and HH 46 IRS show deep ice absorption bands superposed on steeply rising mid-infrared continua. The ices likely originate in the circumstellar envelopes. The CO_2 bending mode at 15 μm is a particularly powerful tracer of the ice composition and processing history. Toward these protostars, this band shows little evidence for thermal processing at temperatures above 50 K. Signatures of lower temperature processing are present in the CO and OCN^- bands, however. The observed CO2 profile indicates an intimate mixture with H_(2)O, but not necessarily with CH_(3)OH, in contrast to some high-mass protostars. This is consistent with the low CH_(3)OH abundance derived from the ground-based L-band spectra. The CO_2 : H_(2)O column density ratios are high in both B5 IRS1 and HH 46 IRS (~35%). Clearly, the Spitzer spectra are essential for studying ice evolution in low-mass protostellar environments and for eventually determining the relation between interstellar and solar system ices

Kinematic frames and "active longitudes": does the Sun have a face?

It has recently been claimed that analysis of Greenwich sunspot data over 120 years reveals that sunspot activity clusters around two longitudes separated by 180 degrees (``active longitudes'') with clearly defined differential rotation during activity cycles.In the present work we extend this critical examination of methodology to the actual Greenwich sunspot data and also consider newly proposed methods of analysis claiming to confirm the original identification of active longitudes. Our analysis revealed that values obtained for the parameters of differential rotation are not stable across different methods of analysis proposed to track persistent active longitudes. Also, despite a very thorough search in parameter space, we were unable to reproduce results claiming to reveal the century-persistent active longitudes. We can therefore say that strong and well substantiated evidence for an essential and century-scale persistent nonaxisymmetry in the sunspot distribution does not exist.Comment: 14 pages, 1 table, 21 figures, accepted in A&

Space storable engine characterization Final report

Space storable turbomachinery configuration and thrust flox/methane pump-fed engine desig