The effect of age and font size on reading text on handheld computers

Though there have been many studies of computer based text reading, only a few have considered the small screens of handheld computers. This paper presents an investigation into the effect of varying font size between 2 and 16 point on reading text on a handheld computer. By using both older and younger participants the possible effects of age were examined. Reading speed and accuracy were measured and subjective views of participants recorded. Objective results showed that there was little difference in reading performance above 6 point, but subjective comments from participants showed a preference for sizes in the middle range. We therefore suggest, for reading tasks, that designers of interfaces for mobile computers provide fonts in the range of 8-12 point to maximize readability for the widest range of users

Identifying the mechanisms underpinning recognition of structured sequences of action

© 2012 The Experimental Psychology SocietyWe present three experiments to identify the specific information sources that skilled participants use to make recognition judgements when presented with dynamic, structured stimuli. A group of less skilled participants acted as controls. In all experiments, participants were presented with filmed stimuli containing structured action sequences. In a subsequent recognition phase, participants were presented with new and previously seen stimuli and were required to make judgements as to whether or not each sequence had been presented earlier (or were edited versions of earlier sequences). In Experiment 1, skilled participants demonstrated superior sensitivity in recognition when viewing dynamic clips compared with static images and clips where the frames were presented in a nonsequential, randomized manner, implicating the importance of motion information when identifying familiar or unfamiliar sequences. In Experiment 2, we presented normal and mirror-reversed sequences in order to distort access to absolute motion information. Skilled participants demonstrated superior recognition sensitivity, but no significant differences were observed across viewing conditions, leading to the suggestion that skilled participants are more likely to extract relative rather than absolute motion when making such judgements. In Experiment 3, we manipulated relative motion information by occluding several display features for the duration of each film sequence. A significant decrement in performance was reported when centrally located features were occluded compared to those located in more peripheral positions. Findings indicate that skilled participants are particularly sensitive to relative motion information when attempting to identify familiarity in dynamic, visual displays involving interaction between numerous features

Factors Associated with Revision Surgery after Internal Fixation of Hip Fractures

Background: Femoral neck fractures are associated with high rates of revision surgery after management with internal fixation. Using data from the Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) trial evaluating methods of internal fixation in patients with femoral neck fractures, we investigated associations between baseline and surgical factors and the need for revision surgery to promote healing, relieve pain, treat infection or improve function over 24 months postsurgery. Additionally, we investigated factors associated with (1) hardware removal and (2) implant exchange from cancellous screws (CS) or sliding hip screw (SHS) to total hip arthroplasty, hemiarthroplasty, or another internal fixation device. Methods: We identified 15 potential factors a priori that may be associated with revision surgery, 7 with hardware removal, and 14 with implant exchange. We used multivariable Cox proportional hazards analyses in our investigation. Results: Factors associated with increased risk of revision surgery included: female sex, [hazard ratio (HR) 1.79, 95% confidence interval (CI) 1.25-2.50; P = 0.001], higher body mass index (fo

Whole-genome sequencing reveals host factors underlying critical COVID-19

Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2,3,4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease

Cognitive differences for learning from computer-based and printed material

Available from British Library Document Supply Centre-DSC:DXN044437 / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

Critical heat capacity of octylcyanobiphenyl (8CB) near the nematic-smectic A transition

An ac technique has been used to measure the heat capacity near the nematic-smectic A (N-SmA) transition in 8CB along isobars at 1, 750 and 1 500 bar. As the pressure is increased, the magnitude of the Cp peak associated with this transition decreases but the shape of the peak remains essentially unchanged. The excess heat capacity at 1 atm. is consistent with a second-order N-SmA transition characterized by an effective critical exponent α = 0.30 ± 0.05.La technique ac a été utilisée pour mesurer la capacité calorifique près de la transition nématiquesmectique A (N-SmA) du composé 8CB le long d'isobars à 1, 750 et 1 500 bar. La grandeur du pic Cp associé à cette transition décroît quand la pression augmente mais la forme du pic reste essentiellement inchangée. La capacité calorifique en excès à 1 atm. est conforme à une transition N-SmA du second ordre, caractérisée par un exposant critique effectif α = 0,30 ± 0,05

Calorimetric study of phase transitions in the liquid crystal butyloxybenzylidene octylaniline (4O.8)

The heat capacity of butyloxybenzylidene octylaniline has been measured from 0° to 95 °C. Significant pretransitional effects are observed near both the first-order transition from the normal rigid crystal to the B phase plastic crystal and the first-order melting transition from the B phase to the smectic-A liquid crystal phase. Data near the second-order smectic-A to nematic transition require a critical exponent α considerably greater than zero, in agreement with recent results on other materials.La capacité calorifique du butyloxybenzylidène octylaniline a été mesurée entre 0° et 95 °C. Des effets prétransitionnels significatifs sont observés non seulement près de la transition du premier ordre entre le cristal rigide normal et la phase cristalline plastique B mais encore près de la transition de fusion du premier ordre entre la phase B et la phase cristal liquide smectique A. Les données au voisinage de la transition du second ordre smectique A-nématique déterminent un exposant critique α très supérieur à zéro, en accord avec des résultats récents obtenus sur d'autres matériaux

Heat capacity measurements near the nematic-smectic-A1 and smectic-A1-smectic-C transitions in octyloxyphenyl cyanobenzyloxy benzoate

The heat capacity Cp of octyloxyphenyl cyanobenzyloxy benzoate (8OPCBOB) has been measured with a high-resolution ac calorimetric technique near the nematic (N)-smectic-A1 (SmA1) and smectic-A1 (SmA1)-smectic- C (SmC) transitions. The SmA1-SmC transition is weakly first order with a Landau-like excess heat capacity (i.e., no excess Cp in the high-temperature SmA1 phase). A detailed analysis of the Cp variation associated with the second-order N-SmA1 transition is presented for 8OPCBOB and for previously published data on a mixture of pentylphenyl-cyanobenzyloxy benzoate (DB5CN) and cyanobenzoyloxypentyl stilbene (C5 stilbene). Both systems exhibit the same critical Cp behavior, which agrees well with the XY model. In particular, the critical amplitude ratio A-/A+ is 0.990, which agrees quite well with the theoretical ratio for the XY model but is qualitatively inconsistent with the expected inverted- XY value. 8OPCBOB and several other systems exhibit a pattern of systematic deviations just below Tc that may be intrinsic to all XY-like N-SmA transitions.La chaleur spécifique (Cp) du benzoate octyloxyphenyl-cyanobenzoxy (8OPCBOB) a été mesurée au voisinage des transitions nématique(N)-smectique-A 1(SmA1) et smectique-A1(SmA1)-smectique- C(SmC) par une technique calorimétrique ac de haute résolution. La transition SmA1- SmC est faiblement du premier ordre avec une chaleur spécifique excédentaire de type Landau (pas de Cp excédentaire dans la phase haute température). Nous présentons une analyse détaillée des variations de Cp du 8OCPBOB, associées à la transition de deuxième ordre N-SmA1, et aussi de données préalablement publiées sur un mélange de benzoate pentylphenyl-cyanobenzoyloxy (DB5CN) et de stilbène cyanobenzoyloxypentyl (C5 stilbène). Les deux systèmes présentent le même comportement critique pour Cp, conformément au modèle XY. En particulier le rapport des amplitudes critiques A-/A+ est 0,990, ce qui est en bon accord avec la valeur théorique pour le modèle XY mais qui est qualitativement en désaccord avec le modèle XY inverse. 8OPCBOB ainsi que quelques autres systèmes présentent des déviations systématiques juste au-dessous de Tc, qui sont probablement intrinsèques à toutes les transitions N-SmA de type XY