On library correctness under weak memory consistency: specifying and verifying concurrent libraries under declarative consistency models

Concurrent libraries are the building blocks for concurrency. They encompass a range of abstractions (locks, exchangers, stacks, queues, sets) built in a layered fashion: more advanced libraries are built out of simpler ones. While there has been a lot of work on verifying such libraries in a sequentially consistent (SC) environment, little is known about how to specify and verify them under weak memory consistency (WMC). We propose a general declarative framework that allows us to specify concurrent libraries declaratively, and to verify library implementations against their specifications compositionally. Our framework is sufficient to encode standard models such as SC, (R)C11 and TSO. Additionally, we specify several concurrent libraries, including mutual exclusion locks, reader-writer locks, exchangers, queues, stacks and sets. We then use our framework to verify multiple weakly consistent implementations of locks, exchangers, queues and stacks

Inhibition of cyclooxygenase-2 decreases breast cancer cell motility, invasion and matrix metalloproteinase expression

BACKGROUND: Cyclooxygenase (COX) is the rate-limiting enzyme that catalyzes the formation of prostaglandins. The inducible isoform of COX (COX-2) is highly expressed in aggressive metastatic breast cancers and may play a critical role in cancer progression (i.e. growth and metastasis). However, the exact mechanism(s) for COX-2-enhanced metastasis has yet to be clearly defined. It is well established that one of the direct results of COX-2 action is increased prostaglandin production, especially prostaglandin E(2 )(PGE(2)). Here, we correlate the inhibition of COX-2 activity with decreased breast cancer cell proliferation, migration, invasion and matrix metalloproteinase (MMP) expression. METHODS: Breast cancer cells (Hs578T, MDA-MB-231 and MCF-7) were treated with selective COX-2 inhibitors (NS-398 and Niflumic acid, NA). Cell proliferation was measured by staining with erythrosin B and counting the viable cells using a hemacytometer. Cell migration and invasion were measured using migration and invasion chamber systems. MMP expression was determined by enzyme immunoassay (secreted protein) and real-time quantitative polymerase chain reaction (mRNA). RESULTS: Our results show that there is a decline in proliferation, migration and invasion by the Hs578T and MDA-MB-231 breast cancer cell lines in the presence of either low concentrations (1 μM or lower) NA or NS-398. We also report that MMP mRNA and protein expression by Hs578T cells is inhibited by NS-398; there was a 50% decrease by 100 μM NS-398. PGE(2 )completely reversed the inhibitory effect of NS-398 on MMP mRNA expression. CONCLUSION: Our data suggests that COX-2-dependent activity is a necessary component for cellular and molecular mechanisms of breast cancer cell motility and invasion. COX-2 activity also modulates the expression of MMPs, which may be a part of the molecular mechanism by which COX-2 promotes cell invasion and migration. The studies suggest that COX-2 assists in determining and defining the metastatic signaling pathways that promote the breast cancer progression to metastasis

Mechanisms underlying the growth inhibitory effects of the cyclo-oxygenase-2 inhibitor celecoxib in human breast cancer cells

INTRODUCTION: Inhibitors of cyclo-oxygenase (COX)-2 are being extensively studied as anticancer agents. In the present study we evaluated the mechanisms by which a highly selective COX-2 inhibitor, celecoxib, affects tumor growth of two differentially invasive human breast cancer cell lines. METHODS: MDA-MB-231 (highly invasive) and MDA-MB-468 (moderately invasive) cell lines were treated with varying concentrations of celecoxib in vitro, and the effects of this agent on cell growth and angiogenesis were monitored by evaluating cell proliferation, apoptosis, cell cycle arrest, and vasculogenic mimicry. The in vitro results of MDA-MB-231 cell line were further confirmed in vivo in a mouse xenograft model. RESULTS: The highly invasive MDA-MB-231 cells express higher levels of COX-2 than do the less invasive MDA-MB-468 cells. Celecoxib treatment inhibited COX-2 activity, indicated by prostaglandin E(2 )secretion, and caused significant growth arrest in both breast cancer cell lines. In the highly invasive MDA-MB-231 cells, the mechanism of celecoxib-induced growth arrest was by induction of apoptosis, associated with reduced activation of protein kinase B/Akt, and subsequent activation of caspases 3 and 7. In the less invasive MDA-MB-468 cells, growth arrest was a consequence of cell cycle arrest at the G(0)/G(1 )checkpoint. Celecoxib-induced growth inhibition was reversed by addition of exogenous prostaglandin E(2 )in MDA-MB-468 cells but not in MDA-MB-231 cells. Furthermore, MDA-MB-468 cells formed significantly fewer extracellular matrix associated microvascular channels in vitro than did the high COX-2 expressing MDA-MB-231 cells. Celecoxib treatment not only inhibited cell growth and vascular channel formation but also reduced vascular endothelial growth factor levels. The in vitro findings corroborated in vivo data from a mouse xenograft model in which daily administration of celecoxib significantly reduced tumor growth of MDA-MB-231 cells, which was associated with reduced vascularization and increased necrosis in the tumor mass. CONCLUSION: The disparate molecular mechanisms of celecoxib-induced growth inhibition in human breast cancer cells depends upon the level of COX-2 expression and the invasive potential of the cell lines examined. Data suggest a role for COX-2 not only in the growth of cancer cells but also in activating the angiogenic pathway through regulating levels of vascular endothelial growth factor

Use of the WHO Access, Watch, and Reserve classification to define patterns of hospital antibiotic use (AWaRe): an analysis of paediatric survey data from 56 countries

BACKGROUND: Improving the quality of hospital antibiotic use is a major goal of WHO's global action plan to combat antimicrobial resistance. The WHO Essential Medicines List Access, Watch, and Reserve (AWaRe) classification could facilitate simple stewardship interventions that are widely applicable globally. We aimed to present data on patterns of paediatric AWaRe antibiotic use that could be used for local and national stewardship interventions. METHODS: 1-day point prevalence survey antibiotic prescription data were combined from two independent global networks: the Global Antimicrobial Resistance, Prescribing, and Efficacy in Neonates and Children and the Global Point Prevalence Survey on Antimicrobial Consumption and Resistance networks. We included hospital inpatients aged younger than 19 years receiving at least one antibiotic on the day of the survey. The WHO AWaRe classification was used to describe overall antibiotic use as assessed by the variation between use of Access, Watch, and Reserve antibiotics, for neonates and children and for the commonest clinical indications. FINDINGS: Of the 23 572 patients included from 56 countries, 18 305 were children (77·7%) and 5267 were neonates (22·3%). Access antibiotic use in children ranged from 7·8% (China) to 61·2% (Slovenia) of all antibiotic prescriptions. The use of Watch antibiotics in children was highest in Iran (77·3%) and lowest in Finland (23·0%). In neonates, Access antibiotic use was highest in Singapore (100·0%) and lowest in China (24·2%). Reserve antibiotic use was low in all countries. Major differences in clinical syndrome-specific patterns of AWaRe antibiotic use in lower respiratory tract infection and neonatal sepsis were observed between WHO regions and countries. INTERPRETATION: There is substantial global variation in the proportion of AWaRe antibiotics used in hospitalised neonates and children. The AWaRe classification could potentially be used as a simple traffic light metric of appropriate antibiotic use. Future efforts should focus on developing and evaluating paediatric antibiotic stewardship programmes on the basis of the AWaRe index. FUNDING: GARPEC was funded by the PENTA Foundation. GARPEC-China data collection was funded by the Sanming Project of Medicine in Shenzhen (SZSM2015120330). bioMérieux provided unrestricted funding support for the Global-PPS

FPGA-based testing strategy for cryptographic chips: A case study on Elliptic Curve Processor for RFID tags

Contains fulltext : 127406.pdf (preprint version ) (Open Access)IOLTS 2009 : 15th IEEE International On-Line Testing Symposium, 24-26 June, 200

Process modelling of combined degumming and bleaching in palm oil refining using artificial neural network

Combined degumming and bleaching is the first stage of processing in a modern physical refining plant. In the current practice, the amount of phosphoric acid (degumming agent) and bleaching earth (bleaching agent) added during this process is usually fixed within a certain range. There is no system that can estimate the right amount of chemicals to be added in accordance with the quality of crude palm oil (CPO) used. The use of an Artificial Neural Network (ANN) for an improved operating procedure was explored in this process. A feed forward neural network was designed using a back-propagation training algorithm. The optimum network for the response factor of phosphoric acid and bleaching earth dosages prediction were selected from topologies with the smallest validation error. Comparisons of ANN predicted results with industrial practice were made. It is proven in this study that ANN can be effectively used to determine the phosphoric acid and bleaching earth dosages for the combined degumming and bleaching process. In fact, ANN gives much more precise required dosages depending on the quality of the CPO used as feedstock. Therefore, the combined degumming and bleaching process can be further optimised with savings in cost and time through the use of ANN

ResourceLog: An Embeddable Tool for Dynamically Monitoring the Usage of Web-Based Bioscience Resources

The present study described an open source application, ResourceLog, that allows website administrators to record and analyze the usage of online resources. The application includes four components: logging, data mining, administrative interface, and back-end database. The logging component is embedded in the host website. It extracts and streamlines information about the Web visitors, the scripts, and dynamic parameters from each page request. The data mining component runs as a set of scheduled tasks that identify visitors of interest, such as those who have heavily used the resources. The identified visitors will be automatically subjected to a voluntary user survey. The usage of the website content can be monitored through the administrative interface and subjected to statistical analyses. As a pilot project, ResourceLog has been implemented in SenseLab, a Web-based neuroscience database system. ResourceLog provides a robust and useful tool to aid system evaluation of a resource-driven Web application, with a focus on determining the effectiveness of data sharing in the field and with the general public

Epidemiological Analysis on 3614 Patients with Temporo-Mandibular Disorders (TMD) Basic Statistical Aspects

The aim of this work was to present data from a large sample of patients with Temporo-Mandibular Disorders (TMD) in order to clarify some aspects of the development of pathological conditions that affect large parts of the population. In the past years there was a rapid growth of the incidence of the temporomandibular dissorders. The ethiopathogenesis is in most cases unclear. Based on the latest information supposed are the biopsychosocial factors