Pay One, Get Hundreds for Free: Reducing Cloud Costs through Shared Query Execution

Cloud-based data analysis is nowadays common practice because of the lower system management overhead as well as the pay-as-you-go pricing model. The pricing model, however, is not always suitable for query processing as heavy use results in high costs. For example, in query-as-a-service systems, where users are charged per processed byte, collections of queries accessing the same data frequently can become expensive. The problem is compounded by the limited options for the user to optimize query execution when using declarative interfaces such as SQL. In this paper, we show how, without modifying existing systems and without the involvement of the cloud provider, it is possible to significantly reduce the overhead, and hence the cost, of query-as-a-service systems. Our approach is based on query rewriting so that multiple concurrent queries are combined into a single query. Our experiments show the aggregated amount of work done by the shared execution is smaller than in a query-at-a-time approach. Since queries are charged per byte processed, the cost of executing a group of queries is often the same as executing a single one of them. As an example, we demonstrate how the shared execution of the TPC-H benchmark is up to 100x and 16x cheaper in Amazon Athena and Google BigQuery than using a query-at-a-time approach while achieving a higher throughput

An innovative approach for DEMO core fuelling by inboard injection of high-speed pellets

Core fuelling of DEMO tokamak fusion reactor is under investigation within the EUROfusion Work Package “Tritium, Fuelling and Vacuum”. An extensive analysis of fuelling requirements and technologies, suggests that pellet injection still represents, to date, the most realistic option. Modelling of both pellet penetration and fuel deposition profiles for different injection locations, assuming a specific plasma reference scenario and the ITER reference pellet mass (6 × 1021 atoms), indicates that: 1) Low Field Side (LFS) injection is inadequate; 2) Vertical injection may be effective only provided that pellets are injected at ∼ 10 km/s from a radial position ≤∼8 m; 3) effective core fuelling can be achieved launching pellets from the High Field Side (HFS) at ∼1 km/s. HFS injection was therefore selected as the reference scheme, though scenarios featuring less steep density and temperature gradients at the plasma edge could induce to reconsider vertical injection at speeds in the range of 4–5 km/s. To deliver intact pellets at 1 km/s from the HFS, the use of guide tubes with a bend radius ≥6 m is envisaged. The results of above simulations rely on the hypothesis that pellets are delivered at the plasma edge with the desired mass and speed. However, mass erosion and fracturing of pellets inside the guide tube (severely limiting the transfer speed), as well as pressure build up and speed losses at relevant injection rates, might hamper the use of curved guide tubes. An additional innovative approach, aimed at identifying inboard straight “free flight” injection paths, to inject pellets from the HFS at significantly higher speeds, is proposed and discussed as a backup solution. Outboard high-speed injection is still being considered, instead, for JT-60SA

The Good, the Bad, and the Ugly: Agonistic Behaviour in Juvenile Crocodilians

We examined agonistic behaviour in seven species of hatchling and juvenile crocodilians held in small groups (N = 4) under similar laboratory conditions. Agonistic interactions occurred in all seven species, typically involved two individuals, were short in duration (5–15 seconds), and occurred between 1600–2200 h in open water. The nature and extent of agonistic interactions, the behaviours displayed, and the level of conspecific tolerance varied among species. Discrete postures, non-contact and contact movements are described. Three of these were species-specific: push downs by C. johnstoni; inflated tail sweeping by C. novaeguineae; and, side head striking combined with tail wagging by C. porosus. The two long-snouted species (C. johnstoni and G. gangeticus) avoided contact involving the head and often raised the head up out of the way during agonistic interactions. Several behaviours not associated with aggression are also described, including snout rubbing, raising the head up high while at rest, and the use of vocalizations. The two most aggressive species (C. porosus, C. novaeguineae) appeared to form dominance hierarchies, whereas the less aggressive species did not. Interspecific differences in agonistic behaviour may reflect evolutionary divergence associated with morphology, ecology, general life history and responses to interspecific conflict in areas where multiple species have co-existed. Understanding species-specific traits in agonistic behaviour and social tolerance has implications for the controlled raising of different species of hatchlings for conservation, management or production purposes

Hadron Spectroscopy with Dynamical Chirally Improved Fermions

We simulate two dynamical, mass degenerate light quarks on 16^3x32 lattices with a spatial extent of 2.4 fm using the Chirally Improved Dirac operator. The simulation method, the implementation of the action and signals of equilibration are discussed in detail. Based on the eigenvalues of the Dirac operator we discuss some qualitative features of our approach. Results for ground state masses of pseudoscalar and vector mesons as well as for the nucleon and delta baryons are presented.Comment: 26 pages, 17 figures, 10 table

The Multidimensional Self-Control Scale (MSCS): Development and validation

Trait self-control is important for well-being and mental and physical health. Most extant measures of self-control are limited in that they do not account for the multidimensionality and specificity of the trait. The aim of this study was to develop and validate a multidimensional and hierarchical scale of self-control in a full and a short version. The development of the Multidimensional Self-Control Scale (MSCS) and the Brief Multidimensional Self-Control Scale (BMSCS) was based on focus groups, a pilot, a main, and a validation sample (total N = 2,409). The 29-item MSCS consists of 6 first-order factors (Procrastination, Attentional Control, Impulse Control, Emotional Control, Goal Orientation, and Self-Control Strategies), 2 second-order factors (Inhibition and Initiation), and a third-order self-control factor. The 8 items in BMSCS provides a general trait self-control score. Findings from exploratory and confirmatory factor analyses supported the structures across samples, and internal consistency was acceptable. Assessment for acquiescence and sex differences indicated no major impacts on the scales. Strong convergent validity was observed with the Self-Control Scale (SCS) and the Brief Self-Control Scale (BSCS), as well as to other similar concepts. The MSCS subscales discriminated well between each other. Assessment of incremental validity of the MSCS over SCS, when controlling for sex and personality, showed significant increases in explained variance when predicting habits, hardiness, and life satisfaction. Similar significant results were observed for the BMSCS over the BSCS. Overall, results indicate that the new scales are useful measures that integrate recent theoretical and empirical findings of trait self-control. (PsycInfo Database Record (c) 2020 APA, all rights reserved)publishedVersio

Opening the Doors of a Substance Use Disorder Ward-Benefits and Challenges From a Consumer Perspective

Open doors in psychiatry have been a subject of controversy in recent years. While some studies postulate the clinical necessity of closed doors, others challenge the theoretical advantages of this setting, mention numerous drawbacks of closed wards, and focus on the advantages of open-door settings. With regard to patients diagnosed with substance use disorders (SUD), other standards may apply. Very little research has been done on this topic. Some studies adopted a consumer perspective (i.e. asking involved parties about their experience of the door status). To the authors' knowledge, no study has so far addressed the ideal setting for the treatment of SUD. With our data from the opening of a specialized SUD ward, we take one step to closing this knowledge gap. Applying a qualitative design, we asked patients and health care professionals (HCP) to report changes following the opening of the ward. The results are mainly in line with the literature on the general psychiatric population. The newly introduced open-door setting was mostly perceived as positive, but some disadvantages were mentioned (e.g. less protection of patients, less control over who enters/leaves the ward, the theoretically increased risk of patients absconding). Moreover, HCP (but not patients) mentioned potentially increased substance use on the ward as an additional disadvantage that could arise. Opening a previously closed ward was generally perceived as a positive and progressive decision. These findings support the trend towards an overall open-door policy in psychiatry

Synovial sepsis of unknown origin in the adult Thoroughbred racehorse

Background: Synovial sepsis of unknown origin is a rare cause of lameness in the adult horse, and a haematogenous pathogenesis has been proposed in previous cases. Objectives: To describe the features and outcome of synovial sepsis of unknown origin in adult Thoroughbred racehorses. Study design: Retrospective case series. Methods: Hospital records for admissions between 2005 and 2015 were reviewed to identify adult horses diagnosed with synovial sepsis of unknown origin. Presentation, clinicopathological, microbiological and diagnostic imaging findings were recorded. Treatment methods, surgical findings, complications and long-term outcome were evaluated. Results: Eleven cases were identified over the study period. Diagnosis was established from clinical examination and clinicopathologic findings, which were comparable to other aetiologies of synovial sepsis. Affected structures included synovial joints, tendon sheaths and bursae. Concurrent osteochondritis dissecans or articular cartilage lesions were evident during arthroscopic surgery in three cases. Significant intrasynovial haemorrhage was not identified. Microbial culture of synovial fluid or synovial biopsy was positive in 6/11 of cases, with all isolates being Gram-positive cocci. Of the 6 positive microbial cultures, all isolates demonstrated in vitro sensitivity to a cephalosporin antimicrobial agent. A concurrent remote wound was present in a single case. No other potential origins of bacteraemia were identified. Treatment methods included endoscopic surgery, standing multineedle lavage, intravenous regional limb perfusion, intrasynovial medication and/or systemic antimicrobial administration. All horses survived to hospital discharge. For the 6/11 cases that raced following synovial sepsis, the median period for return to racing was 221 days. Main limitations: A small study population, which was retrospectively reviewed. Conclusions: Synovial sepsis of unknown origin is rare in the adult Thoroughbred racehorse and can affect a range of synovial structures. A concurrent potential source of bacteraemia is rarely identified. With appropriate management, the prognosis to return to racing is fair