The exp-log normal form of types

Lambda calculi with algebraic data types lie at the core of functional programming languages and proof assistants, but conceal at least two fundamental theoretical problems already in the presence of the simplest non-trivial data type, the sum type. First, we do not know of an explicit and implemented algorithm for deciding the beta-eta-equality of terms---and this in spite of the first decidability results proven two decades ago. Second, it is not clear how to decide when two types are essentially the same, i.e. isomorphic, in spite of the meta-theoretic results on decidability of the isomorphism. In this paper, we present the exp-log normal form of types---derived from the representation of exponential polynomials via the unary exponential and logarithmic functions---that any type built from arrows, products, and sums, can be isomorphically mapped to. The type normal form can be used as a simple heuristic for deciding type isomorphism, thanks to the fact that it is a systematic application of the high-school identities. We then show that the type normal form allows to reduce the standard beta-eta equational theory of the lambda calculus to a specialized version of itself, while preserving the completeness of equality on terms. We end by describing an alternative representation of normal terms of the lambda calculus with sums, together with a Coq-implemented converter into/from our new term calculus. The difference with the only other previously implemented heuristic for deciding interesting instances of eta-equality by Balat, Di Cosmo, and Fiore, is that we exploit the type information of terms substantially and this often allows us to obtain a canonical representation of terms without performing sophisticated term analyses

High pressure pre-treatments promote higher rate and degree of enzymatic hydrolysis of cellulose

The effect of high pressure (HP) pre-treatments on the subsequent enzymatic hydrolysis of cellulose from bleached kraft Eucalyptus globulus pulp by cellulase from Tricoderma viride was evaluated. Pressure pre-treatments of 300 and 400 MPa during 5–45 min, lead to both an increased rate and degree of hydrolysis, reaching values ranging from 1.5- to 1.9-fold, quantified by the formation of reducing sugars. Both the pressure and time under pressure influenced the enzymatic hydrosability of the cellulosic pulps, with the former being more important. The results indicate that the pressure pre-treatments promoted an increased accessibility of cellulose towards cellulase in the cell wall. The results obtained open promising possibilities, to contribute to overcome conventional limitations of enzymatic cellulose hydrolysis for the production of fermentable glucose, for the production of second generation bioethanol and chemicals by enhancement of both rate and yield of hydrolysis. The results are also of interest for the preparation of “pressure engineered” celullose with incremented tailored hydrolysis patterns

Adverse drug reaction monitoring on antiretroviral therapy in human immunodeficiency virus patients in a tertiary care hospital

Background: The aim of current study was to assess the pattern of adverse drug reactions (ADRs) in patients receiving antiretroviral (ARV) therapy.Methods: A prospective, observational study was carried out for duration of 15 months. Clinical and treatment data were collected from patients, who underwent ARV therapy during the study period. CDSCO forms were used to record the ADRs. Causality, severity and preventability were assessed by suitable scales.Result: Out of 216 patients 165 (76%) patients develop ADRs. Total of 274 ADRs were noted among 165 patients (1.66 ADR/patient). Out of them 100 (60.60%) were males and 65 (39.39%) were females. The most common ADR was gastrointestinal disorders (83, 30.29%). The most numbers of ADRs were observed in ZLN (Zidovudine + Lamivudine + Nevirapine) regimen (54%) followed by SLN (Stavudine + Lamivudine + Nevirapine) regimen (26%). According to WHO causality assessment scale most ADRs were possible (236, 86.13%). Hartwig and Siegel severity scale show 243 (88.69%) ADRs were moderate. Schumock and Thornton scale show all, ADRs were “not preventable.”Conclusion: Early detection of drug toxicity helps to treat the patient and modify the drug regimen to minimize toxic effects

Thalassemia mutations in Gaziantep, Turkey

Ninety-eight postnatal and six prenatal cases of thalassemia were studied by the reverse dot-blot hybridization technique in the city of Gaziantep, Turkey. We found the following mutations: IVS 1.110 (G>A) in 29.1%, IVS 2.1 (G>A) in 12.3%, IVS 1.1 (G>A) in 7.7%, Codon 8 (-AA) in 5.6%, -30 (T>A) in 4.6%, IVS 1.6 (T>C) in 4.6%, Codon 39 (C>T) in 3.6%, Codon 44 (-C) in 3.1%, IVS 2.745 (C>G) in 1.5%, Codon 8/9 (+G) in 2.1%, Codon 36/37 (-T) in 2.1%, IVS 1.5 (G>C) in 2.1%, Codon 22 (7pb del) in 0.5%, Codon 5 (-CT) in 0.5% while 20.9% were undetermined. 54 of the thalassemia patients were homozygotes, 12 were compound heterozygous and 31 were heterozygotes. In one allele of 5 thalassemia patients, - thalassemia mutation (3.7 single gene deletions in 1 patient, anti-3.7 gene triplication in 4 patients) wasdetermined at the same time. Finally, this is the first comprehensive study in this region and percentage of and - globin genes mutation is 2.6 and 79.4%, respectively

Extensional Rewriting with Sums

Abstract. Inspired by recent work on normalisation by evaluation for sums, we propose a normalising and confluent extensional rewriting theory for the simply-typed λ-calculus extended with sum types. As a corollary of confluence we obtain decidability for the extensional equational theory of simply-typed λ-calculus extended with sum types. Unlike previous decidability results, which rely on advanced rewriting techniques or advanced category theory, we only use standard techniques.

Isomorphisms of types in the presence of higher-order references (extended version)

We investigate the problem of type isomorphisms in the presence of higher-order references. We first introduce a finitary programming language with sum types and higher-order references, for which we build a fully abstract games model following the work of Abramsky, Honda and McCusker. Solving an open problem by Laurent, we show that two finitely branching arenas are isomorphic if and only if they are geometrically the same, up to renaming of moves (Laurent's forest isomorphism). We deduce from this an equational theory characterizing isomorphisms of types in our language. We show however that Laurent's conjecture does not hold on infinitely branching arenas, yielding new non-trivial type isomorphisms in a variant of our language with natural numbers

Influence of moisture contents on the fast pyrolysis of trommel fines in a bubbling fluidized bed reactor

In this study, the effect of moisture contents [2.69 wt% (bone-dry), 5 wt% and 10 wt%] on product yields and process conversion efficiency during fast pyrolysis of a pre-treated trommel fines feedstock was investigated at 500 °C. Experiments were carried out using a 300 g h −1 bubbling fluidised bed rig. Yields of organic liquids ranged from 15.2 to 19.6 wt% of feedstock, which decreased with increasing moisture content. Hence, the bone-dry feedstock gave the maximum yield and consequently the highest process conversion efficiency of 43%. Increased moisture content also led to increase formation of unidentified gas products, indicating increased conversion of organic liquids. Due to the high ash content of the feedstocks, about 52 wt% solid residues, containing around 82% ash was recovered in the char pot in each case. Hence, to maximize oil yields during fast pyrolysis, trommel fines would require extensive drying to remove the original 46 wt% moisture as well as reducing the ash content considerably. XRF analysis of the ash in the feedstock and solid residues showed that the main elements present included Ca, Si, Fe, Pb, K, Cl and Al. Apart from the presence of Pb (which may be from the glass contents of the feedstock), the solid residues could be used for land reclamation or co-incinerated at cement kilns for cement manufacture