A complete analytical solution for the inverse instantaneous kinematics of a spherical-revolute-spherical (7R) redundant manipulator

Using a method based upon resolving joint velocities using reciprocal screw quantities, compact analytical expressions are generated for the inverse solution of the joint rates of a seven revolute (spherical-revolute-spherical) manipulator. The method uses a sequential decomposition of screw coordinates to identify reciprocal screw quantities used in the resolution of a particular joint rate solution, and also to identify a Jacobian null-space basis used for the direct solution of optimal joint rates. The results of the screw decomposition are used to study special configurations of the manipulator, generating expressions for the inverse velocity solution for all non-singular configurations of the manipulator, and identifying singular configurations and their characteristics. Two functions are therefore served: a new general method for the solution of the inverse velocity problem is presented; and complete analytical expressions are derived for the resolution of the joint rates of a seven degree of freedom manipulator useful for telerobotic and industrial robotic application

A bystander programme to prevent domestic violence and abuse in UK general communities: evaluation of Active Bystander Communities

This is the author accepted manuscript. the final version is available from Elsevier via the DOI in this recordBristol City CouncilDevon County CouncilPublic Health England South WestUniversity of Exete

Competing mechanisms of stress-assisted diffusivity and stretch-activated currents in cardiac electromechanics

We numerically investigate the role of mechanical stress in modifying the conductivity properties of the cardiac tissue and its impact in computational models for cardiac electromechanics. We follow a theoretical framework recently proposed in [Cherubini, Filippi, Gizzi, Ruiz-Baier, JTB 2017], in the context of general reaction-diffusion-mechanics systems using multiphysics continuum mechanics and finite elasticity. In the present study, the adapted models are compared against preliminary experimental data of pig right ventricle fluorescence optical mapping. These data contribute to the characterization of the observed inhomogeneity and anisotropy properties that result from mechanical deformation. Our novel approach simultaneously incorporates two mechanisms for mechano-electric feedback (MEF): stretch-activated currents (SAC) and stress-assisted diffusion (SAD); and we also identify their influence into the nonlinear spatiotemporal dynamics. It is found that i) only specific combinations of the two MEF effects allow proper conduction velocity measurement; ii) expected heterogeneities and anisotropies are obtained via the novel stress-assisted diffusion mechanisms; iii) spiral wave meandering and drifting is highly mediated by the applied mechanical loading. We provide an analysis of the intrinsic structure of the nonlinear coupling using computational tests, conducted using a finite element method. In particular, we compare static and dynamic deformation regimes in the onset of cardiac arrhythmias and address other potential biomedical applications

Breakdown of weak-field magnetotransport at a metallic quantum critical point

We show how the collapse of an energy scale in a quantum critical metal can lead to physics beyond the weak-field limit usually used to compute transport quantities. For a density-wave transition we show that the presence of a finite magnetic field at the critical point leads to discontinuities in the transport coefficients as temperature tends to zero. The origin of these discontinuities lies in the breakdown of the weak field Jones-Zener expansion which has previously been used to argue that magneto-transport coefficients are continuous at simple quantum critical points. The presence of potential scattering and magnetic breakdown rounds the discontinuities over a window determined by tau Delta < 1 where Delta is the order parameter and tau is the quasiparticle elastic lifetime.Comment: 4 pages, 3 figures RevTeX forma

The role of iconic gestures and mouth movements in face-to-face communication

Human face-to-face communication is multimodal: it comprises speech as well as visual cues, such as articulatory and limb gestures. In the current study, we assess how iconic gestures and mouth movements influence audiovisual word recognition. We presented video clips of an actress uttering single words accompanied, or not, by more or less informative iconic gestures. For each word we also measured the informativeness of the mouth movements from a separate lipreading task. We manipulated whether gestures were congruent or incongruent with the speech, and whether the words were audible or noise vocoded. The task was to decide whether the speech from the video matched a previously seen picture. We found that congruent iconic gestures aided word recognition, especially in the noise-vocoded condition, and the effect was larger (in terms of reaction times) for more informative gestures. Moreover, more informative mouth movements facilitated performance in challenging listening conditions when the speech was accompanied by gestures (either congruent or incongruent) suggesting an enhancement when both cues are present relative to just one. We also observed (a trend) that more informative mouth movements speeded up word recognition across clarity conditions, but only when the gestures were absent. We conclude that listeners use and dynamically weight the informativeness of gestures and mouth movements available during face-to-face communication

Remote sensing in Iowa agriculture: Identification and classification of Iowa's crops, soils and forestry resources using ERTS-1 and complimentary underflight imagery

There are no author-identified significant results in this report

QZ Serpentis: A Dwarf Nova with a 2-Hour Orbital Period and an Anomalously Hot, Bright Secondary Star

We present spectroscopy and time-series photometry of the dwarf nova QZ Ser. The spectrum shows a rich absorption line spectrum of type K4 +- 2. K-type secondary stars are generally seen in dwarf novae with orbital periods P-orb around 6 h, but in QZ Ser the absorption radial velocities show an obvious modulation (semi-amplitude 207(5) km/s) at P-orb = 119.752(2) min, much shorter than typical for such a relatively warm and prominent secondary spectrum. The H-alpha emission-line velocity is modulated at the same period and roughly opposite phase. Time-series photometry shows flickering superposed on a modulation with two humps per orbit, consistent with ellipsoidal variation of the secondary's light. QZ Ser is a second example of a relatively short-period dwarf nova with a surprisingly warm secondary. Model calculations suggest that the secondary is strongly enhanced in helium, and had already undergone significant nuclear evolution when mass transfer began. Several sodium absorption features in the secondary spectrum are unusually strong, which may indicate that the present-day surface was the site of CNO-cycle hydrogen burning in the past.Comment: 11 pages, 3 postscript figures, 1 jpeg greyscale figure. Accepted for publication in PAS

Validity of Criteria for Dementia in Older People With Intellectual Disability

Objective: Valid definitions of dementia should discriminate dementia from other forms of cognitive impairment such as intellectual disability (ID). We aimed to evaluate the usefulness of criteria for dementia and mild cognitive impairment (MCI) in ID, including predictive validity, and inter-rater reliability. / Method: We assessed 222 participants in a survey of older adults with ID without Down syndrome at two time points for dementia (T1 and T2). Mean follow-up period was 2.9 years. Dementia diagnoses were made according to International Classification of Diseases, Tenth Revision, Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition), Diagnostic criteria for psychiatric disorders for use with adults with learning disabilities (DC-LD) criteria. At follow-up (T2), raters were blind to initial diagnosis. Predictive validity was determined by comparing odds ratios (ORs) of death, or of having a “poor outcome” (i.e., either dying or being diagnosed with dementia at T2). / Results: All dementia criteria showed substantial inter-rater reliability (κ > 0.68) and high specificity (∼95%). Dementia cases at T1 were more likely to have died at T2 than those with no dementia (33.3% versus 14.9%; OR: 2.85; 95% confidence interval (95% CI): 1.12–7.22) and to have a “poor outcome” (77.8% versus 27.6%; OR: 9.18; 95% CI: 3.43–24.53). At least two dementia cases at T1 were false positives. Those with “MCI” at T1 were similar to “no dementia” cases in terms of poor outcomes at T2. / Conclusion: Dementia diagnostic criteria show substantial reliability and satisfactory validity in ID. The diagnoses were, however, less stable than in the general population and some caution is advisable in those with more severe ID or additional sensory disability. MCI definitions require further consideration in the ID population