Safe Locking Policies for Dynamic Databases

AbstractYannakakis showed that a locking policy is not safe if and only if it allows a canonical nonserializable schedule of transactions in which all transactions except one are executed serially (Yannakakis, 1982). In the present paper, we study the generalization of this result to a dynamic database, that is, a database that may undergo insertions and deletions of entities. We illustrate the utility of this generalization by applying it to obtain correctness proofs of three locking policies that handle dynamic databases

A moist-thermal quasigeostrophic model for monsoon depressions

Funding: AKC is supported by a St Leonard’s College Interdisciplinary Doctoral Scholarship awarded by the University of St Andrews.Monsoon depressions (MDs) are synoptic-scale storms that occur during the summer phase of the global monsoon cycle and whose dynamical mechanisms remain incompletely understood. To gain insight into the dynamics governing the large-scale structure of MDs, we formulate an idealised moist-thermal quasi-geostrophic model that includes distinct thermal and moisture fields in simple forms. A linear-stability analysis of the model, with basic states corresponding to typical monsoon conditions, shows three distinct mode classifications: thermal-Rossby modes, heavy precipitating modes, and a moist-thermal mode. In the linearised model, the presence of a background precipitation gradient strengthens thermal-Rossby modes by coupling the dynamics to latent heating. The separation of heavy precipitating modes from fast-propagating thermal-Rossby modes is further examined with numerical experiments of large-amplitude MDs. Wind-induced evaporation is found to amplify large-amplitude MDs in conditions analogous to those over the northern Bay of Bengal. An energetic analysis shows the pathways by which the MDs derive energy from the background state. A further series of experiments through a continuum of meridional temperature gradients demonstrates the sensitivity of large-scale MD dynamics to the background state and suggests a possible mechanism to explain variations in the propagation direction of MDs.Peer reviewe

Comparative analysis of knowledge representation and reasoning requirements across a range of life sciences textbooks.

BackgroundUsing knowledge representation for biomedical projects is now commonplace. In previous work, we represented the knowledge found in a college-level biology textbook in a fashion useful for answering questions. We showed that embedding the knowledge representation and question-answering abilities in an electronic textbook helped to engage student interest and improve learning. A natural question that arises from this success, and this paper's primary focus, is whether a similar approach is applicable across a range of life science textbooks. To answer that question, we considered four different textbooks, ranging from a below-introductory college biology text to an advanced, graduate-level neuroscience textbook. For these textbooks, we investigated the following questions: (1) To what extent is knowledge shared between the different textbooks? (2) To what extent can the same upper ontology be used to represent the knowledge found in different textbooks? (3) To what extent can the questions of interest for a range of textbooks be answered by using the same reasoning mechanisms?ResultsOur existing modeling and reasoning methods apply especially well both to a textbook that is comparable in level to the text studied in our previous work (i.e., an introductory-level text) and to a textbook at a lower level, suggesting potential for a high degree of portability. Even for the overlapping knowledge found across the textbooks, the level of detail covered in each textbook was different, which requires that the representations must be customized for each textbook. We also found that for advanced textbooks, representing models and scientific reasoning processes was particularly important.ConclusionsWith some additional work, our representation methodology would be applicable to a range of textbooks. The requirements for knowledge representation are common across textbooks, suggesting that a shared semantic infrastructure for the life sciences is feasible. Because our representation overlaps heavily with those already being used for biomedical ontologies, this work suggests a natural pathway to include such representations as part of the life sciences curriculum at different grade levels

Carbon Ion irradiation in the treatment of grossly incomplete or unresectable malignant peripheral nerve sheaths tumors: acute toxicity and preliminary outcome

Background: To report our early experience with carbon ion irradiation in the treatment of gross residual or unresectable malignant peripheral nerve sheath tumors (MPNST). Methods: We retrospectively analysed 11 patients (pts) with MPNST, who have been treated with carbon ion irradiation (C12) at our institution between 2010 and 2013. All pts had measurable gross disease at the initiation of radiation treatment. Median age was 47 years (29-79). Tumors were mainly located in the pelvic/sacral (5 pts) and sinunasal/orbital region (5 pts). 5 pts presented already in recurrent situation, 3 pts had been previously irradiated, and in 3 pts MPNST were neurofibromatosis type 1 (NF1) associated. Median cumulative dose was 60 GyE. Treatment was carried out either as a combination of IMRT plus C12 boost (4 pts) or C12 only (7 pts). Results: Median follow-up was 17 months (3-31 months). We observed 3 local progressions, translating into estimated 1- and 2-year local control rates of 65%. One patient developed distant failure, resulting in estimated 1- and 2-year PFS rates of 56%. Two patients have died, therefore the estimated 1- and 2-year OS rates are 75%. Acute radiation related toxicities were generally mild, no grade 3 side effects were observed. Severe late toxicity (grade 3) was scored in 2 patients (trismus, wound healing delays). Conclusion: Carbon ion irradiation yields very promising short term local control and overall survival rates with low morbidity in patients suffering from gross residual or unresectable malignant peripheral nerve sheath tumors and should be further investigated in a prospective trial

Dengue: multicentre clinical profile of patients admitted in intensive care unit

Background: Dengue with 2.5 billion people at risk and 50 million new cases every year is one of the most rapidly spreading vectors borne disease in world. We aimed to analyse the clinical profile of dengue patients requiring ICU admission.Methods: In a cross-sectional, observational, multicenter case study 105randomly selected laboratory positive dengue subjects were randomly selected from four tertiary care centers ICU’s. Socio-demographical, clinical, therapeutic & laboratory parameters were evaluated. Statistical analysis was done using SPSS version 14.0.Results: The main cause of ICU admission was shock or hypotension due to sepsis (20%). Most patients presenting complaint was fever (93.33%), bodyache (84.76%) and retro-orbital pain (34.3%). Most prevalent warning sign indicating severe dengue was abdominal pain (37.4%). Mucosal bleed (20.9%) was the most common haemorrhagic manifestation. 37.14% with warning signs and 62.86% patients with severe dengue required ICU care.Conclusions: A rapid assessment of clinical profile, presenting symptoms and warning signs can aid in early decision for requirement of ICU admission & may go a long way in decreasing mortality

A study to investigate the prevalence of metabolic syndrome in Chronic Obstructive Pulmonary Disease patients from North India

Background: Worldwide, Chronic obstructive pulmonary disease (COPD) is the one of the leading cause of chronic morbidity and mortality. COPD is one of the diseases in which smoking is the common and important risk factor when it is associated with Metabolic syndrome (MetS). The individual components of MetS, i.e., obesity, dyslipidemia, fasting hyperglycaemia, and hypertension were independently associated with impairment of lung function too. The objective of this study is to find out the prevalence of metabolic syndrome among COPD patients.Methods: This was a cross-sectional study conducted in department of Respiratory Diseases and a total of 70 COPD patients were included in the study, which were enrolled for treatment from July 2016 to July 2017. The severity level in patients with COPD were determined according to GOLD (Global Initiative for Chronic Obstructive Lung Disease), 2015 guideline. International Diabetes Federation (IDF) guideline; (2005) was used in diagnosis of metabolic syndrome.Results: Seventy patients with COPD were enrolled during the study period. There were 45 males (64.2%) and 25(35.7%) females. Mean age of male patients was 58.67±9.87 years, while mean age of female patients was 57.23±10.4 years (35-87 years). Mean BMI of male was 24.33±6.64 kg/m2, while in case of female it was 30.07±6.95 kg/m2 and overall mean BMI of study population was 26.22±7.22 kg/m2. The mean   waist circumference of male was 86.91±13.31 cm while in female it was 87.18±14.51 cm. The Overall prevalence of metabolic syndrome was 31.34% and most common in GOLD stage-3 (47.06%), followed by stage-2 (40%), followed by stage-4 (25.71%) and 7.4 % in GOLD stage -1.Conclusions: The presence of metabolic syndrome is common in patients with COPD and, all COPD patients should be considered for screening for it

An ontological approach to creating an Andean Weaving Knowledge Base

Andean textiles are products of one of the richest, oldest and continuous weaving traditions in the world. Understanding the knowledge and practice of textile production as a form of cultural heritage is particularly relevant in the Andean context due to erosion of clothing traditions, reuse of traditional textiles on commodities targeted at the tourism market, and loss of knowledge embedded in textile production. ``Weaving Communities of Practice'' was a pilot project that aimed to create a knowledge base of Andean weaving designed to contribute to curatorial practice and heritage policy. The research team gathered data on the chain of activities, instruments, resources, peoples, places and knowledge involved in the production of textiles, relating to over 700 textile samples. A major part of the project has been the modelling and representation of the knowledge of domain experts and information about the textile objects themselves in the form of an OWL ontology, and the development of a suite of search facilities to be supported by the ontology. This paper describes the research challenges faced in developing the ontology and search facilities, the methodology adopted, the design and implementation of the system, and the design and outcomes of a user evaluation of the system undertaken with a group of domain experts