On Global Warming (Softening Global Constraints)

We describe soft versions of the global cardinality constraint and the regular constraint, with efficient filtering algorithms maintaining domain consistency. For both constraints, the softening is achieved by augmenting the underlying graph. The softened constraints can be used to extend the meta-constraint framework for over-constrained problems proposed by Petit, Regin and Bessiere.Comment: 15 pages, 7 figures. Accepted at the 6th International Workshop on Preferences and Soft Constraint

Modelling the circular economy: Introducing a supply chain equilibrium approach

The circular economy (CE) has gained prominence in recent years in government and business policies, as well as academic research. Yet, its alleged wholesomeness is increasingly questioned and few quantitative studies include both the outer (e.g. recycling) and inner circles (e.g. reduce or reuse), respectively the ex-ante least and most efficient CE strategies. By developing a supply chain equilibrium model, based on general equilibrium theory, this paper presents a modelling framework where a product-service system is introduced as a circular alternative to conventional products. Through generalised prices that cover inner and outer circle variables, targeted economic and fiscal policy measures affect overall price levels and, by consequence, operational levels of the supply chain. The rationale behind this approach relies on combining material and economic efficiency by integrating material/product life cycles with market interactions. To illustrate its performance, the model examines the rollout of a reusable plastic bottle initiative in Belgium. The results show that if circular products are perceived as substitutes for conventional products, well-targeted policies can reduce material use substantially. Furthermore, coordinating circular policies along the supply chain can improve their outcomes. However, the absence of CE data impedes model development and risks undermining the validity of the results

Anatomic features underlying wood density, in 110 rainforest tree species from central Congo basin

Investigate the influence of fiber thickness and vessel diameter on the wood density in 110 rainforest tree species, and the relationships between wood density, wood water content and shrinking ratio.COBIMF

Nurses’ and patients’ experiences and preferences of the Ankle-Brachial Pressure Index and Multi-site Photoplethysmography for the diagnosis of peripheral arterial disease: A qualitative study

Peripheral arterial disease is a global health problem, affecting around 20% of people aged over 60 years. Whilst ankle-brachial pressure index (ABPI) is regularly used for diagnosis, it has a number of limitations, which have presented a need for alternative methods of diagnosis. Multi-site photoplethysmography (MPPG) is one such method, but evidence of acceptability of both methods is lacking. This study aims to describe and compare preferences and experiences amongst nurses and patients of ABPI and MPPG use in primary care. We used qualitative research methods in the context of a clinical diagnostic study comparing ABPI with MPPG. Use of ABPI and MPPG by 13 nurses were observed with 51 patients across general practice surgeries in North-East England in 2015/16. Follow-up semi-structured interviews were conducted with 12 nurses and 27 patients. Data were thematically analysed. Two major themes were identified: (1) device preferences; (2) test discomfort and anxiety. There was a compelling preference for MPPG due to ease of use, speed of the test, patient comfort, and perceived device accuracy/objectivity. However some patients struggled to identify a preference, describing ambivalence to medical testing. ABPI was deemed uncomfortable and painful, particularly when the blood pressure cuff was inflated at the lower limbs. There was also evidence of anxiety amongst patients when their foot pulses were not identified using ABPI. Whilst ABPI is a non-invasive and routine procedure it was associated with a number of drawbacks in clinical practice. Nurses required considerable dexterity to employ the test, and it resulted in anxiety amongst some patients. Conversely, MPPG was deemed to be easier and quicker to use, and perceived to be less subjective. Should diagnostic accuracy and cost be comparable to ABPI, then the findings of this study suggest MPPG would be preferable to ABPI for patients as well as nurses

Looking inside the black box : a theory-based process evaluation alongside a randomised controlled trial of printed educational materials (the Ontario printed educational message, OPEM) to improve referral and prescribing practices in primary care in Ontario, Canada

Background: Randomised controlled trials of implementation strategies tell us whether (or not) an intervention results in changes in professional behaviour but little about the causal mechanisms that produce any change. Theory-based process evaluations collect data on theoretical constructs alongside randomised trials to explore possible causal mechanisms and effect modifiers. This is similar to measuring intermediate endpoints in clinical trials to further understand the biological basis of any observed effects (for example, measuring lipid profiles alongside trials of lipid lowering drugs where the primary endpoint could be reduction in vascular related deaths). This study protocol describes a theory-based process evaluation alongside the Ontario Printed Educational Message (OPEM) trial. We hypothesize that the OPEM interventions are most likely to operate through changes in physicians' behavioural intentions due to improved attitudes or subjective norms with little or no change in perceived behavioural control. We will test this hypothesis using a well-validated social cognition model, the theory of planned behaviour (TPB) that incorporates these constructs. Methods/design: We will develop theory-based surveys using standard methods based upon the TPB for the second and third replications, and survey a subsample of Ontario family physicians from each arm of the trial two months before and six months after the dissemination of the index edition of informed, the evidence based newsletter used for the interventions. In the third replication, our study will converge with the "TRY-ME" protocol (a second study conducted alongside the OPEM trial), in which the content of educational messages was constructed using both standard methods and methods informed by psychological theory. We will modify Dillman's total design method to maximise response rates. Preliminary analyses will initially assess the internal reliability of the measures and use regression to explore the relationships between predictor and dependent variable (intention to advise diabetic patients to have annual retinopathy screening and to prescribe thiazide diuretics for first line treatment of uncomplicated hypertension). We will then compare groups using methods appropriate for comparing independent samples to determine whether there have been changes in the predicted constructs (attitudes, subjective norms, or intentions) across the study groups as hypothesised, and will assess the convergence between the process evaluation results and the main trial results.The OPEM trial and OPEM process evaluation are funded by the Canadian Institute of Health Research (CIHR). The OPEM process evaluation study was developed as part of the CIHR funded interdisciplinary capacity enhancement team KT-ICEBeRG. Gaston Godin, Jeremy Grimshaw and France Légaré hold Canada Research Chairs. Louise Lemyre holds an R.S. McLaughlin Research Chair

How can we possibly resolve the planet’s nitrogen dilemma?

Peer reviewe

Crystallographic control on the substructure of nacre tablets

Nacre tablets of mollusks develop two kinds of features when either the calcium carbonate or the organic portions are removed: (1) parallel lineations (vermiculations) formed by elongated carbonate rods, and (2) hourglass patterns, which appear in high relief when etched or in low relief if bleached. In untreated tablets, SEM and AFM data show that vermiculations correspond to aligned and fused aragonite nanogloblules, which are partly surrounded by thin organic pellicles. EBSD mapping of the surfaces of tablets indicates that the vermiculations are invariably parallel to the crystallographic a-axis of aragonite and that the triangles are aligned with the b-axis and correspond to the advance of the {010} faces during the growth of the tablet. According to our interpretation, the vermiculations appear because organic molecules during growth are expelled from the a-axis, where the Ca–CO3 bonds are the shortest. In this way, the subunits forming nacre merge uninterruptedly, forming chains parallel to the a-axis, whereas the organic molecules are expelled to the sides of these chains. Hourglass patterns would be produced by preferential adsorption of organic molecules along the {010}, as compared to the {100} faces. A model is presented for the nanostructure of nacre tablets. SEM and EBSD data also show the existence within the tablets of nanocrystalline units, which are twinned on {110} with the rest of the tablet. Our study shows that the growth dynamics of nacre tablets (and bioaragonite in general) results from the interaction at two different and mutually related levels: tablets and nanogranules

Bcl-xL acts as an inhibitor of IP3R channels, thereby antagonizing Ca2+-driven apoptosis

Anti-apoptotic Bcl-2-family members not only act at mitochondria but also at the endoplasmic reticulum, where they impact Ca dynamics by controlling IP receptor (IPR) function. Current models propose distinct roles for Bcl-2 vs. Bcl-xL, with Bcl-2 inhibiting IPRs and preventing pro-apoptotic Ca release and Bcl-xL sensitizing IPRs to low [IP] and promoting pro-survival Ca oscillations. We here demonstrate that Bcl-xL too inhibits IPR-mediated Ca release by interacting with the same IPR regions as Bcl-2. Via in silico superposition, we previously found that the residue K87 of Bcl-xL spatially resembled K17 of Bcl-2, a residue critical for Bcl-2’s IPR-inhibitory properties. Mutagenesis of K87 in Bcl-xL impaired its binding to IPR and abrogated Bcl-xL’s inhibitory effect on IPRs. Single-channel recordings demonstrate that purified Bcl-xL, but not Bcl-xL, suppressed IPR single-channel openings stimulated by sub-maximal and threshold [IP]. Moreover, we demonstrate that Bcl-xL-mediated inhibition of IPRs contributes to its anti-apoptotic properties against Ca-driven apoptosis. Staurosporine (STS) elicits long-lasting Ca elevations in wild-type but not in IPR-knockout HeLa cells, sensitizing the former to STS treatment. Overexpression of Bcl-xL in wild-type HeLa cells suppressed STS-induced Ca signals and cell death, while Bcl-xL was much less effective in doing so. In the absence of IPRs, Bcl-xL and Bcl-xL were equally effective in suppressing STS-induced cell death. Finally, we demonstrate that endogenous Bcl-xL also suppress IPR activity in MDA-MB-231 breast cancer cells, whereby Bcl-xL knockdown augmented IPR-mediated Ca release and increased the sensitivity towards STS, without altering the ER Ca content. Hence, this study challenges the current paradigm of divergent functions for Bcl-2 and Bcl-xL in Ca-signaling modulation and reveals that, similarly to Bcl-2, Bcl-xL inhibits IPR-mediated Ca release and IPR-driven cell death. Our work further underpins that IPR inhibition is an integral part of Bcl-xL’s anti-apoptotic function.The work was supported by Grants from the Research Foundation—Flanders (FWO) (G.0901.18N), by the Research Council of the KU Leuven (OT14/101, C14/19/099, C14/19/101, and AKUL/19/34), the Interuniversity Attraction Poles Program (Belgian Science Policy; IAP-P7/13), the Central European Leuven Strategic Alliance (CELSA/18/040), and the Canadian Institutes Health Research (FDN143312). NR and HI are recipient of postdoctoral fellowships of the FWO; HI obtained a travel grant from the FWO to perform work in DIY’s laboratory. GB, JBP and DIY are part of the FWO Scientific Research Network CaSign (W0.019.17N). Work in DIY’s lab is supported by NIH (NIDCR) grant DE014756. DWA holds the Tier 1 Canada Research Chair in Membrane Biogenesis. The Switch laboratory was supported by the Flanders institute for Biotechnology (VIB), the University of Leuven, the Fund for Scientific Research Flanders (Hercules Foundation/FWO AKUL/15/34—G0H1716N). NL is funded by the Stichting Alzheimer Onderzoek (SAO-FRA 2020/0013) and is recipient of FWO postdoctoral fellowships (12P0919N and 12P0922N to NL)