Uniqueness of Normal Forms is Decidable for Shallow Term Rewrite Systems

Uniqueness of normal forms (UN=) is an important property of term rewrite systems. UN= is decidable for ground (i.e., variable-free) systems and undecidable in general. Recently it was shown to be decidable for linear, shallow systems. We generalize this previous result and show that this property is decidable for shallow rewrite systems, in contrast to confluence, reachability and other properties, which are all undecidable for flat systems. Our result is also optimal in some sense, since we prove that the UN= property is undecidable for two superclasses of flat systems: left-flat, left-linear systems in which right-hand sides are of depth at most two and right-flat, right-linear systems in which left-hand sides are of depth at most two

On the Structure of Counterexamples to Symmetric Orderings for BDD's

AbstractBinary Decision Diagrams (BDDs) are used to represent boolean functions in a variety of applications. The size of a reduced ordered BDD depends on the ordering of variables. Several researchers have suggested grouping symmetric variables as a promising heuristic for finding good orderings. In this paper we study the conjecture which states that symmetric variables gather in at least one of the optimum variable orders. First, we prove some useful properties of partially symmetric functions. Next, we develop a faster procedure for finding counterexamples to this conjecture that exploits the partitioning of boolean functions into nn-equivalence classes. Third, we study the structure of counterexamples and devise a new and simple method to generate new counterexamples from given counterexamples. Finally, we present different kinds of counterexamples, which show that boolean functions are very diverse with respect to where symmetric orders can fall in the range from optimal orders to worst-case orders

To assess awareness regarding rational drug therapy and fixed dose combinations amongst interns and II MBBS students in tertiary care teaching hospital in Maharashtra, India

Background: The present study was designed to assess awareness regarding rational drug therapy and fixed dose combinations (FDC) amongst interns and II MBBS students in a tertiary-care teaching hospital in Maharashtra, India.Methods: This cross-sectional, questionnaire-based study containing MCQ and analytical questions on rational drug therapy, fixed dose combinations and role of Pharmacist in dispensing correct drug to the patients was carried out in both interns (n=80) and II MBBS students (n=100). The completed questionnaires were then collected and analysed statistically for responses.Results: Mean average score obtained by II MBBS students (score - 36.66marks) was significantly better than interns (score- 20marks) which probably may be due to pharmacology teaching they were undergoing. II MBBS students were found to be better informed as compared to the interns (p0.05). However, on question related to justification of FDC, interns were found to be better informed as compared to the II MBBS students (p<0.05). On single question pertaining to role of pharmacist, interns were found to be better informed than II MBBS students possibly due to their better understanding of patient-pharmacist relationship.Conclusions: Our study highlights the significance regarding knowledge of rational drug therapy and fixed dose combination (both rational and irrational), both rational and irrational, amongst both interns and II MBBS students while identifying the possible areas of interventions to make them rational clinicians

A Third Order based Additional Regularization in Intrinsic Space of the Manifold

Second order graph Laplacian regularization has the limitation that the solution remains biased towards a constant which restricts its extrapolationcapability. The lack of extrapolation results in poor generalization. An additional penalty factor is needed on the function to avoid its over-fitting on seen unlabeled training instances. The third order derivative based technique identifies the sharp variations in the function and accurately penalizes them to avoid overfitting. The resultant function leads to a more accurate and generic model that exploits the twist and curvature variations on the manifold. Extensive experiments on synthetic and real-world data set clearly shows thatthe additional regularization increases accuracy and generic nature of model

Comparison of concomitant boost radiotherapy against concurrent chemoradiation in locally advanced oropharyngeal cancers: A phase III randomised trial

AbstractPurposeTo test the toxicity and efficacy of concomitant boost radiotherapy alone against concurrent chemoradiation (conventional fractionation) in locally advanced oropharyngeal cancer in our patient population.Methods and materialsIn this open-label, randomised trial, 216 patients with histologically proven Stage III–IVA oropharyngeal cancer were randomly assigned between June 2006 and December 2010 to receive either chemoradiation (CRT) to a dose of 66Gy in 33 fractions over 6.5weeks with concurrent cisplatin (100mg/m2 on days 1, 22 and 43) or accelerated radiotherapy with concomitant boost (CBRT) to a dose of 67.5Gy in 40 fractions over 5weeks. The compliance, toxicity and quality of life were investigated. Disease-free survival (DFS) and overall survival (OS) curves were estimated with the Kaplan–Meier method and compared using log rank test.ResultsThe compliance to radiotherapy was superior in concomitant boost with lesser treatment interruptions (p=0.004). Expected acute toxicities were significantly higher in CRT, except for grade 3/4 mucositis which was seen more in CBRT arm (39% and 55% in CRT and CBRT, respectively; p=0.02). Late toxicities like Grade 3 xerostomia were significantly high in CRT arm than CBRT arm (33% versus 18%; p<0.0001). The quality of life was significantly poor in CRT arm at all follow up visits (p<0.0001). The rates of 2year disease-free survival were similar with 56% in the chemoradiotherapy group and 61% in CBRT group (p=0.2; HR-0.81, 95%CI-0.53–1.2). Subgroup analysis revealed that patients with nodal size >2cm had significantly better DFS with CRT (p=0.05; HR-1.59, 95%CI-0.93–2.7).ConclusionIn selected patients of locally advanced oropharyngeal cancer, concomitant boost offers a better compliance, toxicity profile and quality of life with similar disease control, than chemoradiation

Narrative-based computational modelling of the Gp130/JAK/STAT signalling pathway.

BACKGROUND: Appropriately formulated quantitative computational models can support researchers in understanding the dynamic behaviour of biological pathways and support hypothesis formulation and selection by "in silico" experimentation. An obstacle to widespread adoption of this approach is the requirement to formulate a biological pathway as machine executable computer code. We have recently proposed a novel, biologically intuitive, narrative-style modelling language for biologists to formulate the pathway which is then automatically translated into an executable format and is, thus, usable for analysis via existing simulation techniques. RESULTS: Here we use a high-level narrative language in designing a computational model of the gp130/JAK/STAT signalling pathway and show that the model reproduces the dynamic behaviour of the pathway derived by biological observation. We then "experiment" on the model by simulation and sensitivity analysis to define those parameters which dominate the dynamic behaviour of the pathway. The model predicts that nuclear compartmentalisation and phosphorylation status of STAT are key determinants of the pathway and that alternative mechanisms of signal attenuation exert their influence on different timescales. CONCLUSION: The described narrative model of the gp130/JAK/STAT pathway represents an interesting case study showing how, by using this approach, researchers can model biological systems without explicitly dealing with formal notations and mathematical expressions (typically used for biochemical modelling), nevertheless being able to obtain simulation and analysis results. We present the model and the sensitivity analysis results we have obtained, that allow us to identify the parameters which are most sensitive to perturbations. The results, which are shown to be in agreement with existing mathematical models of the gp130/JAK/STAT pathway, serve us as a form of validation of the model and of the approach itself