Full-field and anomaly initialization using a low-order climate model: a comparison and proposals for advanced formulations

Initialization techniques for seasonal-to-decadal climate predictions fall into two main categories; namely full-field initialization (FFI) and anomaly initialization (AI). In the FFI case the initial model state is replaced by the best possible available estimate of the real state. By doing so the initial error is efficiently reduced but, due to the unavoidable presence of model deficiencies, once the model is let free to run a prediction, its trajectory drifts away from the observations no matter how small the initial error is. This problem is partly overcome with AI where the aim is to forecast future anomalies by assimilating observed anomalies on an estimate of the model climate. The large variety of experimental setups, models and observational networks adopted worldwide make it difficult to draw firm conclusions on the respective advantages and drawbacks of FFI and AI, or to identify distinctive lines for improvement. The lack of a unified mathematical framework adds an additional difficulty toward the design of adequate initialization strategies that fit the desired forecast horizon, observational network and model at hand. Here we compare FFI and AI using a low-order climate model of nine ordinary differential equations and use the notation and concepts of data assimilation theory to highlight their error scaling properties. This analysis suggests better performances using FFI when a good observational network is available and reveals the direct relation of its skill with the observational accuracy. The skill of AI appears, however, mostly related to the model quality and clear increases of skill can only be expected in coincidence with model upgrades. We have compared FFI and AI in experiments in which either the full system or the atmosphere and ocean were independently initialized. In the former case FFI shows better and longer-lasting improvements, with skillful predictions until month 30. In the initialization of single compartments, the best performance is obtained when the stabler component of the model (the ocean) is initialized, but with FFI it is possible to have some predictive skill even when the most unstable compartment (the extratropical atmosphere) is observed. Two advanced formulations, least-square initialization (LSI) and exploring parameter uncertainty (EPU), are introduced. Using LSI the initialization makes use of model statistics to propagate information from observation locations to the entire model domain. Numerical results show that LSI improves the performance of FFI in all the situations when only a portion of the system's state is observed. EPU is an online drift correction method in which the drift caused by the parametric error is estimated using a short-time evolution law and is then removed during the forecast run. Its implementation in conjunction with FFI allows us to improve the prediction skill within the first forecast year. Finally, the application of these results in the context of realistic climate models is discussed

Sensory Outcomes in Digital Nerve Repair Techniques: An Updated Meta-Analysis and Systematic Review

Introduction: Injuries to the digital nerves are common with trauma to the hand; surgery is often required to repair injured nerves. Surgical management of digital nerve injuries includes neurorrhaphy or use of allograft, autografts, and conduits. Objective: In light of the increasing availability and utilization of digital nerve repair constructs, an updated meta-analysis was undertaken in order to comparatively review the available evidence to determine differences in outcomes. Methods: We reviewed the most current literature on sensory outcomes of various digital nerve repair techniques using static two-point discrimination (S2PD), moving two-point discrimination (M2PD), Semmes Weinstein–Monofilament testing (SWMF) and complication rates as outcomes of interest. After inclusion and exclusion criteria were applied, 15 articles were reviewed and 625 nerve repairs were analyzed. Results: In terms of S2PD outcomes, autograft repair was found to have the highest percent of repairs with “good” and “excellent” sensory outcome followed by allograft repair, conduit repair, and neurorrhaphy (95% vs. 80% vs. 78% vs. 76%). In terms of SWMF outcomes, autograft repair reported the highest percentage of “normal” and “diminished light touch” sensation, followed by allograft, neurorrhaphy, and conduit repair (95% vs. 70% vs. 59% vs. 47%). Of the studies that reported complications, allograft repair had the highest complication rate (9%). Discussion: Combining “good” and “excellent” S2PD results and “normal” and “diminished light touch” SWMF showed that autograft repair may yet still provide the best sensory outcome results in repair of injured digital nerves. Allograft repair may pose the greatest risk for complication

DNA amplified fingerprinting, a useful tool for determination of genetic origin and diversity analysis in Citrus

We used three short repetitive nucleotide sequences [(GTG)5, (TAC)5, and (GACA)4] either as radiolabeled probes for hybridization with restricted Citrus DNA or as single primers in polymerase chain reaction amplification experiments with total genomic DNA. We tested the ability of the sequences to discriminate between seedlings of zygotic or nuclear origin in the progeny of a Volkamer lemon #Citrus volkameriana# Ten. & Pasq.) tree. The genetic variability within two species [#Citrus sinensis# (L.) Osbeck (sweet oranges) and #Citrus reticulata# Blanco and relatives (mandarins)] was evaluated. DNA amplified figerprinting with single primers was the more successful technique for discriminating between nucellular and zygotic seedlings. Although we were not able to distinguish among 10 cultivars of #C. sinensis#, all 10 #C. reticulata# cultivars tested were distinguishable. However, it still is difficult to identify the putative parents of a hybrid plant when the two parental genomes are closely related. (Résumé d'auteur

Seeing new opportunities to help smokers quit: A UK national survey of optometrist delivered smoking cessation behavioural support interventions

Background: Smoking is a risk factor for various eye conditions. Brief smoking cessation interventions have demonstrated effectiveness when delivered by a range of healthcare professionals. Optometrists are well-placed in the community to advise otherwise healthy smokers to quit, yet remain relatively neglected in smoking cessation research and policy. In a national survey, this study investigated self-reported practices of UK optometrists for delivering brief tobacco smoking cessation interventions to patients. Methods: A randomly selected sample of 1,200 optometrists out of the 9000 optometrists registered on the UK College of Optometrists database were invited to complete a 40-item, web-based survey assessing: training related to smoking cessation; current practice [i.e. the proportion of patients to which components of very brief advice (Ask, Advise, Assist) and other evidence-based smoking cessation behaviour change techniques were delivered]; and barriers/enablers to intervention delivery. Results: In total, 408 (34%) responses were received. Most (83%) optometrists received no training in practical skills for delivering smoking cessation support. A third (34%) routinely assessed smoking status. Fewer self-reported advising smokers to quit (22%), offering assistance (via referral to dedicated services) (3%), or advice on smoking cessation medications (2%). Perceived barriers included insufficient knowledge/training (81%) and time (65%). Optometrists were more likely to assess and advise on smoking cessation if they practised in Scotland (χ²(2)=32.95,  p<0.001), an independent optometry practice (χ²(1)=4.27,  p=0.39), or had received smoking cessation training χ²(1)=13.1,  p<0.001). Conclusions: Substantial gaps exist in UK optometrists' current smoking cessation training and practice. Evidence-based training resources are needed to support the implementation of smoking cessation interventions into routine optometry practice. Implications: Optometrists are well placed in the community to delivery brief advice interventions to a large population of smokers. This survey provides a comprehensive description of current UK optometry practice related to the provision of evidence-based brief tobacco smoking cessation interventions to patients. Although optometrists perceive advising on smoking cessation as part of their role, numerous substantial gaps in current practice and training remain which need to be addressed through targeted interventions to increase implementation