Speeding up the constraint-based method in difference logic

"The final publication is available at http://link.springer.com/chapter/10.1007%2F978-3-319-40970-2_18"Over the years the constraint-based method has been successfully applied to a wide range of problems in program analysis, from invariant generation to termination and non-termination proving. Quite often the semantics of the program under study as well as the properties to be generated belong to difference logic, i.e., the fragment of linear arithmetic where atoms are inequalities of the form u v = k. However, so far constraint-based techniques have not exploited this fact: in general, Farkas’ Lemma is used to produce the constraints over template unknowns, which leads to non-linear SMT problems. Based on classical results of graph theory, in this paper we propose new encodings for generating these constraints when program semantics and templates belong to difference logic. Thanks to this approach, instead of a heavyweight non-linear arithmetic solver, a much cheaper SMT solver for difference logic or linear integer arithmetic can be employed for solving the resulting constraints. We present encouraging experimental results that show the high impact of the proposed techniques on the performance of the VeryMax verification systemPeer ReviewedPostprint (author's final draft

A Doubly Nudged Elastic Band Method for Finding Transition States

A modification of the nudged elastic band (NEB) method is presented that enables stable optimisations to be run using both the limited-memory quasi-Newton (L-BFGS) and slow-response quenched velocity Verlet (SQVV) minimisers. The performance of this new `doubly nudged' DNEB method is analysed in conjunction with both minimisers and compared with previous NEB formulations. We find that the fastest DNEB approach (DNEB/L-BFGS) can be quicker by up to two orders of magnitude. Applications to permutational rearrangements of the seven-atom Lennard-Jones cluster (LJ7) and highly cooperative rearrangements of LJ38 and LJ75 are presented. We also outline an updated algorithm for constructing complicated multi-step pathways using successive DNEB runs.Comment: 13 pages, 8 figures, 2 table

The reactivity of cyclopropyl cyanide in titan's atmosphere: a possible pre-biotic mechanism

Cyclopropyl cyanide and other simple nitriles detected in Titan's atmosphere could be precursors leading to the formation of organic macromolecules in the atmosphere of Saturn's largest satellite. Proposing a thermodynamically possible mechanism that explains their formation and supports experimental results represents a difficult challenge. Experiments done in the Atomic and Molecular Physics Laboratory at the University of Trento (AMPL) have studied the ion-molecule reaction between cyclopropyl cyanide and its protonated form, with reaction products being characterized by mass spectrometry. In addition to the expected ion-molecule adduct stabilized by non-covalent long-range interactions, in this work we prove that another distinct species having the same mass to charge ratio (m/z) of 135 is also produced. Moreover, from a previous study of the neutral cyclopropyl cyanide potential energy surface (PES) which shows a partial biradical character it has been possible to characterize the formation through the bimolecular reaction of a new covalent cyclic organic molecule. Calculations have been carried out at the ab initio Møller-Plesset (MP2) level of theory, ensuring the connectivity of the stationary points by using the intrinsic reaction coordinate (IRC) procedure. In order to characterize the reaction transition state, multireference calculations were done using a complete active space involving six electrons and six molecular orbitals [CAS (6 e, 6 m.o.)]. This study opens the possibility of exploring the formation of new organic molecules by gaseous phase ion-molecule interaction schemes, with such molecules having relevance in interstellar space and in astrobiology (and may be involved in prebiotic molecular evolution)

Equity, barriers and cancer disparities: study of the Spanish Society of Medical Oncology on the access to oncologic drugs in the Spanish Regions

[Purpose] The Spanish Society of Medical Oncology (SEOM) has conducted a study on the access to oncologic drugs across the 17 Spanish Regions with the aim of identifying potential heterogeneities and making proposals for eliminating the barriers identified at the different levels.[Methods] An Expert Panel made up of medical oncologists designed a survey on certain indications approved for 11 drugs in the approach of breast cancer, melanoma, lung cancer, prostate cancer and support treatment. This survey was sent to 144 National Health System (NHS) hospitals. [Results] 77 hospitals answered the survey. The information modules analysed were: scope of the Commission that establishes binding decisions related to drug access; conditions, stages and periods of drug application, approval and administration processes; barriers to accessing drugs. [Conclusions] The study shows variability in drug access. The SEOM makes proposals addressed to reducing the differences identified and homogenizing drug access conditions.This study was funded by SEOM

Effects of epidural lidocaine analgesia on labor and delivery: A randomized, prospective, controlled trial

BACKGROUND: Whether epidural analgesia for labor prolongs the active-first and second labor stages and increases the risk of vacuum-assisted delivery is a controversial topic. Our study was conducted to answer the question: does lumbar epidural analgesia with lidocaine affect the progress of labor in our obstetric population? METHOD: 395 healthy, nulliparous women, at term, presented in spontaneous labor with a singleton vertex presentation. These patients were randomized to receive analgesia either, epidural with bolus doses of 1% lidocaine or intravenous, with meperidine 25 to 50 mg when their cervix was dilated to 4 centimeters. The duration of the active-first and second stages of labor and the neonatal apgar scores were recorded, in each patient. The total number of vacuum-assisted and cesarean deliveries were also measured. RESULTS: 197 women were randomized to the epidural group. 198 women were randomized to the single-dose intravenous meperidine group. There was no statistical difference in rates of vacuum-assisted delivery rate. Cesarean deliveries, as a consequence of fetal bradycardia or dystocia, did not differ significantly between the groups. Differences in the duration of the active-first and the second stages of labor were not statistically significant. The number of newborns with 1-min and 5-min Apgar scores less than 7, did not differ significantly between both analgesia groups. CONCLUSION: Epidural analgesia with 1% lidocaine does not prolong the active-first and second stages of labor and does not increase vacuum-assisted or cesarean delivery rate

Standardising outcome reporting for clinical trials of interventions for heavy menstrual bleeding: Development of a core outcome set

OBJECTIVE: To develop a core outcome set for heavy menstrual bleeding (HMB). DESIGN: Core outcome set (COS) development methodology described by the COMET initiative. SETTING: University hospital gynaecology department, online international survey and web-based international consensus meetings. POPULATION OR SAMPLE: Phase 1: Systematic review of previously reported outcomes to identify potential core outcomes. Phase 2: Qualitative studies with patients to identify outcomes most important to them. Phase 3: Online two-round Delphi survey to achieve consensus about which outcomes are most important. Phase 4: A consensus meeting to finalise the COS. METHODS: Phase 1: Systematic review of previously reported outcomes to identify potential core outcomes. Phase 2: Qualitative studies with patients to identify outcomes most important to them. Phase 3: Online two-round Delphi survey to achieve consensus about which outcomes are most important. Phase 4: A consensus meeting to finalise the COS. MAIN OUTCOME MEASURES: Outcome importance was assessed in the Delphi survey on a 9-point scale. RESULTS: From the ‘long list’ of 114, 10 outcomes were included in the final COS: subjective blood loss; flooding; menstrual cycle metrics; severity of dysmenorrhoea; number of days with dysmenorrhoea; quality of life; adverse events; patient satisfaction; number of patients going on to have further treatment for HMB and haemoglobin level. CONCLUSIONS: The final COS includes variables that are feasible for use in clinical trials in all resource settings and apply to all known underlying causes of the symptom of HMB. These outcomes should be reported in all future trials of interventions, their systematic reviews, and clinical guidelines to underpin policy

A Measurement of the Hadronic Component of Air Showers in a Fine Grained Calorimeter

The hadronic component of extensive air showers is studied using the E594 fine grained calorimeter and a air shower array trigger. Hadron angle and energy distributions are shown. Events with more than one separated hadron with substantial energy are studied carefully. The correlation of hadronic and muonic components is shown. 2 refs., 3 figs

Envejecer en casa con teleasistencia en España. Un análisis del discurso

Caring for the elderly is turning to forms of community care and home care. Telecare is one of those emergent modalities of caring. This article will explore the meanings that older people give to the experience of staying at home in later life by using telecare. Discourse analysis is used to examine a set of focus groups and interviews with telecare users from different cities of Catalonia (Spain). The outcomes include three interpretative repertoires that we called: "Aging at home", "normal aging" and "unsafe aging". For each repertoire we examine how the permanence of older people in their homes is accounted, and which role telecare plays in such experience.El cuidado de las personas mayores está dando un giro hacia modalidades de atención comunitaria y domiciliaria. La teleasistencia es una de dichas modalidades. Este artículo se propone explorar los significados que las personas mayores asocian a la experiencia de permanecer en el hogar a edades avanzadas con ayuda de la teleasistencia. Se utiliza el análisis del discurso para examinar un conjunto de grupos de discusión con y de entrevistas a usuarios de teleasistencia de diferentes ciudades de Cataluña (España). Como resultado se presentan tres repertorios interpretativos denominados: "envejecimiento en casa", "envejecimiento normal" y "envejecimiento inseguro". Para cada uno se examina la forma como describen la permanencia de las personas mayores en sus hogares, así como el papel que la teleasistencia juega en dicha experiencia

Lipid-lowering drugs in ischaemic heart disease : a quasi-experimental uncontrolled before-and-after study of the effectiveness of clinical practice guidelines

Background: Cardiovascular diseases(CVD), specifically ischaemic heart disease(IHD), are the main causes of death in industrialized countries. Statins are not usually prescribed in the most appropriate way. To ensure the correct prescription of these drugs, it is necessary to develop, disseminate and implement clinical practice guidelines(CPGs), and subsequently evaluate them. The main objective of this study is to evaluate the effectiveness of the implementation of consensual Lipid-lowering drugs (LLD) prescription guidelines in hospital and primary care settings, to improve the control of Low-Density Lipoprotein Cholesterol (LDL-C) levels in patients with IHD in the Terres de l'Ebre region covered by the Catalonian Health Institute. Secondary bjectives are to assess the improvement of the prescription profile of these LLDs, to assess cardiovascular morbimortality and the professional profile and participant centre characteristics that govern the control of LDL-C. Methods/Design Design: Quasi-experimental uncontrolled before and after study. The intervention consists of the delivery of training strategies for guideline implementation (classroom clinical sessions and on-line courses) aimed at primary care and hospital physicians. The improvement in the control of LDL-C levels in the 3,402 patients with IHD in our territory is then assessed. Scope: Primary care physicians from 11 basic health areas(BHAs) and two hospital services (internal medicine and cardiology). Sample: 3,402 patients registered with IHD in the database of the Catalan Institute of Health(E-cap) before December 2008 and patients newly diagnosed during 2009-2010. Variables: Percentage of patients achieving good control of LDL-C, measured in milligrams per decilitre. The aim of the intervention is to achieve levels of LDL-C < 100 mg/dl in patients with IHD. Secondary variables measure type and time of diagnosis of IHD, type and dose of prescribed cholesterol-lowering drugs, level of physician participation in training activities and their professional profile. Discussion: The development of prescription guidelines previously agreed by various medical specialists involved in treating IHD patients have usually improved drug prescription. The guideline presented in this study aims to improve the control of LDL-C by training physicians through presential and on-line courses on the dissemination of this guideline, and by providing feedback on their personal results a year after this training intervention