Predicting polydisperse granular segregation

Most granular materials in industrial applications and natural settings are size-polydisperse, but most models and simulations of segregation consider only bidisperse particle distributions. Here, we extend our recently developed theoretical advection–diffusion–segregation model to polydisperse particle distributions. To test the theoretical approach, we model and simulate grains log-normally distributed by size in a chute flow. In steady state, material near the free surface is dominated by large particles, whereas the lower regions are composed of mostly small particles. The segregation pattern depends on a single dimensionless control parameter, which is a function of the particle sizes, the diffusion coefficient, the shear rate, and the flowing layer depth. Interestingly, for all values of the control parameter, the overall log normal particle size distribution is approximately maintained at each spatial location, but with different mean and variance than the overall particle distribution. To confirm the theoretical results, we use discrete element method (DEM) simulations using a general purpose graphics processing unit. Quantitative agreement is found between theory and DEM simulations. Funded by the Dow Chemical Company

Aortic valvuloplasty of calcific aortic stenosis with monofoil and trefoil balloon catheters: practical considerations

In order to evaluate the relation between balloon design (monofoil, trefoil) and valvular configuration, experimental aortic valvuloplasty was performed in four post-mortem hearts with calcific aortic sten

Very Early Smoke Detection Apparatus (VESDA), David Packham, John Petersen, Martin Cole: 2017 DiNenno Prize

The 2017 Phillip J. DiNenno Prize was awarded to the innovators of the VESDA smoke detection system. The initialtechnology was invented and patented byDavid PackhamandLen Gibson, who worked withJohn Petersenonprototype development, field trials, and applications engineering.Dr. Martin Colewas responsible for the successfulcommercial development and many further patented technical developments. The VESDA technology and its pre-eminent role in the introduction of aspirated smoke detection (ASD) internationally has led to a major global impacton public safety.The recipients of the 2017 Philip J. DiNenno Prize areDavid Packham,John Petersen,andDr. Martin Cole.Amplecommendation is given to their deceased co-inventor and passionate advocateLen Gibson.Otherimportantcontributions are noted, including technical and other staff from IEI, CSIRO, SSL and Telecom Australia

The cyclic nucleotide cGMP is involved in plant hormone signalling and alters phosphorylation of Arabidopsis thaliana root proteins

The cyclic nucleotide cGMP has been shown to play important roles in plant development and responses to abiotic and biotic stress. Yet much controversy remains regarding the exact role of this second messenger. Progress in unravelling cGMP function in plants was hampered by laborious and time-consuming methodology to measure changes in cellular [cGMP] but the development of fluorescence-based reporters has removed this disadvantage. This study used the FlincG cGMP reporter to investigate potential interactions between phytohormone and cGMP signalling and found a rapid and significant effect of the hormones abscisic acid (ABA), auxin (IAA), and jasmonic acid (JA) on cytoplasmic cGMP levels. In contrast, brassinosteroids and cytokinin did not evoke a cGMP signal. The effects of ABA, IAA, and JA were apparent at external concentrations in the nanomolar range with EC50 values of around 1000, 300, and 0.03 nmoles for ABA, IAA, and JA respectively. To examine potential mechanisms for how hormone-induced cGMP signals are propagated, the role of protein phosphorylation was tested. A phosphoproteomics analysis on Arabidopsis thaliana root microsomal proteins in the absence and presence of membrane-permeable cGMP showed 15 proteins that rapidly (within minutes) changed in phosphorylation status. Out of these, nine were previously shown to also alter phosphorylation status in response to plant hormones, pointing to protein phosphorylation as a target for hormone-induced cGMP signalling

Heterologous expression of the yeast arsenite efflux system ACR3 improves Arabidopsis thaliana tolerance to arsenic stress

Arsenic contamination has a negative impact on crop cultivation and on human health. As yet, no proteins have been identified in plants that mediate the extrusion of arsenic. Here, we heterologously expressed the yeast (Saccharomyces cerevisiae) arsenite efflux transporter ACR3 into Arabidopsis to evaluate how this affects plant tolerance and tissue arsenic contents. ACR3 was cloned from yeast and transformed into wild-type and nip7;1 Arabidopsis. Arsenic tolerance was determined at the cellular level using vitality stains in protoplasts, in intact seedlings grown on agar plates and in mature plants grown hydroponically. Arsenic efflux was measured from protoplasts and from intact plants, and arsenic levels were measured in roots and shoots of plants exposed to arsenate. At the cellular level, all transgenic lines showed increased tolerance to arsenite and arsenate and a greater capacity for arsenate efflux. With intact plants, three of four stably transformed lines showed improved growth, whereas only transgenic lines in the wild-type background showed increased efflux of arsenite into the external medium. The presence of ACR3 hardly affected tissue arsenic levels, but increased arsenic translocation to the shoot. Heterologous expression of yeast ACR3 endows plants with greater arsenic resistance, but does not lower significantly arsenic tissue levels

Long-Term Prognosis of Diabetic Patients With Critical Limb Ischemia: A population-based cohort study

OBJECTIVE\u2014 To evaluate the long-term prognosis of critical limb ischemia (CLI) in diabetic patients. RESEARCH DESIGN AND METHODS\u2014 A total of 564 consecutive diabetic patients were hospitalized for CLI from January 1999 to December 2003; 554 were followed until December 2007. RESULTS\u2014 The mean follow-up was 5.93 1.28 years. Peripheral angioplasty (PTA) was performed in 420 (74.5%) and bypass graft (BPG) in 117 (20.6%) patients. Neither PTA nor BPG were possible in 27 (4.9%) patients. Major amputations were performed in 74 (13.4%) patients: 34 (8.2%) in PTA, 24 (21.1%) in BPG, and 16 (59.2%) in a group that received no revascularization. Restenosis occurred in 94 patients, bypass failures in 36 patients, and recurrent ulcers in 71 patients. CLI was observed in the contralateral limb of 225 (39.9%) patients; of these, 15 (6.7%) required major amputations (rate in contralateral compared with initial limb, P 0.007). At total of 276 (49.82%) patients died. The Cox model showed significant hazard ratios (HRs) for mortality with age (1.05 for 1 year [95% CI 1.03\u20131.07]), unfeasible revascularization (3.06 [1.40\u20136.70]), dialysis (3.00 [1.63\u20135.53]), cardiac disease history (1.37 [1.05\u20131.79]), and impaired ejection fraction (1.08 for 1% point [1.05\u20131.09]). CONCLUSIONS\u2014 Diabetic patients with CLI have high risks of amputation and death. In a dedicated diabetic foot center, the major amputation, ulcer recurrence, and major contralateral limb amputation rates were low. Coronary artery disease (CAD) is the leading cause of death, and in patients with CAD history the impaired ejection fraction is the major independent prognostic factor

KIN7 kinase regulates the vacuolar TPK1 K+ channel during stomatal closure

Stomata are leaf pores that regulate CO 2 uptake and evapotranspirational water loss. By controlling CO 2 uptake, stomata impact on photosynthesis and dry matter accumulation. The regulation of evapotranspiration is equally important because it impacts on nutrient accumulation and leaf cooling and enables the plant to limit water loss during drought [1]. Our work centers on stomatal closure [2–6]. This involves loss of potassium from the guard cell by a two-step process. Salt is released across the plasma membrane via anion channels such as SLAC1 [7–9] and depolarization-activated channels such as GORK [10, 11], with the net result that cations and anions exit guard cells. However, this critically depends on K + release from the vacuole; with ∼160 and 100 mM K + in cytoplasm and vacuole of open guard cells [12], vacuolar K + efflux is driven by the negative tonoplast potential, and this expels K + from the vacuole via tonoplast K + channels like TPK1. In all, guard cell salt release leads to a loss of turgor that brings about stomatal closure. First, we show that the TPK1 vacuolar K + channel is important for abscisic acid (ABA)- and CO 2-mediated stomatal closure. Second, we reveal that, during ABA- and CO 2-mediated closure, TPK1 is phosphorylated and activated by the KIN7 receptor-like protein kinase (RLK), which co-expresses in the tonoplast and plasma membrane. The net result is K + release from the vacuole. Taken together, our work reveals new components involved in guard cell signaling and describes a new mechanism potentially involved in fine-tuning ABA- and CO 2-induced stomatal closure. Stomatal closure critically depends on K + release from the guard cell vacuole. Isner et al. show that the TPK1 vacuolar K + channel is important for ABA- and CO 2-mediated stomatal closure and that channel activation involves TPK1 phosphorylation by the KIN7 receptor-like protein kinase, which co-expresses in the tonoplast and plasma membrane

Charlie Chaplin and gesture training in severe aphasia: A controlled double-blind single-case experimental design

Background Aphasia following a stroke is a frequent and disabling condition that decreases quality of life. The use of gesture has been proposed as a way to enhance aphasia recovery. Objective We aimed to explore whether 2 types of gesture interventions could improve communication in individuals with severe aphasia. Methods This was a pilot study performed at home in routine care by an outreach team. The study had a controlled double-blind single-case experimental design (SCED): a controlled multiple baseline design across 3 participants and 2 behaviors (gesture and naming). Three male patients with stroke-induced severe chronic aphasia, non-functional perseverative speech and severe associated impairments underwent a passive gesture intervention, in which participants watched movies selected for their intensive use of gesture, and an active gesture intervention, in which they actively practiced gestures by using visual action therapy. The main outcome measures were naming score, gesture score and nonverbal subscale score of the Lillois Test of Communication, with 3-month follow-up. Results In all 3 participants, gesture interventions improved the ability to gesture a list of words (Tau-U = 0.38–0.67 for combined gesture intervention effect) and increased nonverbal communication activity. Benefits were maintained at 3-month follow-up. Conclusions Mute films that use intensive nonverbal communication may be a useful add-on to speech therapy for individuals with aphasia. Improving naming in severe and chronic aphasia may not be feasible, and more effort could be devoted to improving gesture-based and nonverbal communication