1,236 research outputs found
Solid Silica-based Sulphonic Acid as an Efficient Green Catalyst for the Selective Oxidation of Sulphides to Sulphoxides using NaCIO in Aqueous Media
A range of sulphides can be selectively oxidized to the corresponding sulphoxides in good yields using NaClO/silica sulphonic acid as an efficient and recyclable solid acid catalyst, in both water and 50/50 water/EtOH as solvents. The new method compares favourably with previous methods in the literature.Keywords: Silica sulphonic acid, heterogeneous catalyst, oxidation, sulphides, sulphoxide
CONFLLVM: A Compiler for Enforcing Data Confidentiality in Low-Level Code
We present an instrumenting compiler for enforcing data confidentiality in
low-level applications (e.g. those written in C) in the presence of an active
adversary. In our approach, the programmer marks secret data by writing
lightweight annotations on top-level definitions in the source code. The
compiler then uses a static flow analysis coupled with efficient runtime
instrumentation, a custom memory layout, and custom control-flow integrity
checks to prevent data leaks even in the presence of low-level attacks. We have
implemented our scheme as part of the LLVM compiler. We evaluate it on the SPEC
micro-benchmarks for performance, and on larger, real-world applications
(including OpenLDAP, which is around 300KLoC) for programmer overhead required
to restructure the application when protecting the sensitive data such as
passwords. We find that performance overheads introduced by our instrumentation
are moderate (average 12% on SPEC), and the programmer effort to port OpenLDAP
is only about 160 LoC.Comment: Technical report for CONFLLVM: A Compiler for Enforcing Data
Confidentiality in Low-Level Code, appearing at EuroSys 201
Poly(ethylene)glycol/AlCl3 as a Green and Reusable System in the Synthesis of α,α’-bis(substituted-benzylidene) Cycloalkanones
Aluminum chloride has been found to be a highly efficient catalyst for the aldol condensation of aldehydes and cycloketones in poly(ethylene)glycol 400 at room temperature. The reaction is very fast, clean and environmentally benign for the synthesis of a variety of α,α’-bis(substituted-benzylidene) cycloalkanones.Keywords: Aluminum Chloride, Poly(ethylene)glycol, α,α’-bis(substituted-benzylidene) cycloalkanones, Aldol Condensatio
The supplementary irrigation effects on drought tolerance and ornamental characteristics of safflower varieties
Supplementary irrigation is a high-performance operation for increasing crop production and income of farmers in dryland conditions. In order to study the effect of supplementary irrigation on drought tolerance and ornamental characteristics of safflower genotypes an experiment was conducted in 2013-14 at North Khorasan Dryland Agricultural Research Station. The experimental design was split plot based on RCBD. Factors were included five levels of irrigation, i.e., no irrigation, irrigation at rosette stage, flowering stage, seed filling and irrigation in flowering + seed filling as the main factors, and sub factors were varieties in three levels included Feraman, Sina and Syrian. The effect of supplementary irrigation on harvest index, seed/main head, seed/sub head, thousand kernel weight and seed yield was significant. The effect of supplementary irrigation on traits: RGR, CGR, hollow seeds, number of flowers and flower size was not significant. The highest yield and harvest index were obtained with irrigation at flowering stage in "Feraman". Since the "Feraman" variety has shiny red flowers and spineless leaves, is a good plant for flower trade.Keywords: carthamus tinctorius; flower color; optimum irrigation; spineless leaf
CRYSTALLIZATION KINETICS OF GLASS-CERAMICS BY DIFFERENTIAL THERMAL ANALYSIS
The crystallization behavior of fluorphlogopite, a glass-ceramic in the MgO–SiO2–Al2O3–K2O–B2O3–F system, was studied by substitution of Li2O for K2O in the glass composition. DTA, XRD and SEM were used for the study of crystallization behavior, formed phases and microstructure of the resulting glass-ceramics. Crystallization kinetics of the glass was investigated under non-isothermal conditions, using the formal theory of transformations for heterogeneous nucleation. The crystallization results were analyzed, and both the activation energy of crystallization process as well as the crystallization mechanism were characterized. Calculated kinetic parameters indicated that the appropriate crystallization mechanism was bulk crystallization for base glass and the sample with addition of Li2O. Non-isothermal DTA experiments showed that the crystallization activation energies of base glasses was in the range of 234-246 KJ/mol and in the samples with addition of Li2O was changed to the range of 317-322 KJ/mol
Assessment of binding affinity between drugs and human serum albumin using nanoporous anodic alumina photonic crystals
In this study, we report an innovative approach aiming to assess the binding affinity between drug molecules and human serum albumin by combining nanoporous anodic alumina rugate filters (NAA-RFs) modified with human serum albumin (HSA) and reflectometric interference spectroscopy (RIfS). NAA-RFs are photonic crystal structures produced by sinusoidal pulse anodization of aluminum that present two characteristic optical parameters, the characteristic reflection peak (λPeak), and the effective optical thickness of the film (OTeff), which can be readily used as sensing parameters. A design of experiments strategy and an ANOVA analysis are used to establish the effect of the anodization parameters (i.e., anodization period and anodization offset) on the sensitivity of HSA-modified NAA-RFs toward indomethacin, a model drug. To this end, two sensing parameters are used, that is, shifts in the characteristic reflection peak (ΔλPeak) and changes in the effective optical thickness of the film (ΔOTeff). Subsequently, optimized NAA-RFs are used as sensing platforms to determine the binding affinity between a set of drugs (i.e., indomethacin, coumarin, sulfadymethoxine, warfarin, and salicylic acid) and HSA molecules. Our results verify that the combination of HSA-modified NAA-RFs with RIfS can be used as a portable, low-cost, and simple system for establishing the binding affinity between drugs and plasma proteins, which is a critical factor to develop efficient medicines for treating a broad range of diseases and medical conditions.Mahdieh Nemati, Abel Santos, Cheryl Suwen Law, and Dusan Losi
Discourse-Pragmatic and Processing-Related Motivators of the ordering of Reason Clauses in an Academic Corpus
The present research is aimed at examining the relative importance of the competing motivators of the sequencing of reason clauses in a corpus of research articles of applied linguistics. All the finite reason clauses accompanied by their main clauses in this corpus were collected. Random forest of conditional inference trees is the statistical modelling in this study. The findings showed that sentence-final reason clauses outnumber sentenceinitial ones. Moreover, subordinator choice and bridging, which are discourse-pragmatic constraints on clause positioning, emerged as the two more powerful predictors of the ordering of reason clauses in this corpus. Furthermore, the complexity of the clause turned out to be a stronger processing-related predictor than the length of the clause
Effects of Mentha pulegium water extract dipping on quality and shelf life of silver carp (Hypophthalmichthys molitrix) during superchilled storage
The effects of Mentha pulegium water extract dipping on quality and shelf life of silver carp during superchilled storage were investigated. Fish samples were treated with water extract of 1 and 3% M. pulegium, and then stored at -3 οC for 30 days. The control and the treated fish samples were analyzed periodically for chemical (pH, PV, TBA, TVB-N), and sensory characteristics. The results indicated that the effect of M. pulegium extract dipping on fish samples was to retain their good quality characteristics and extend the shelf life during superchilled storage, which was supported by the results of chemical and sensory evaluation analyses. In this respect, the sample supplemented with 3% water extract was more potent compared with the 1% one in extending the shelf life of fish fillets
Nuclear imaging with radiolabeled odor molecules in patients with olfactory disorder
Smell loss originates from peripheral
disorders, like intranasal obstruction
and olfactory cell injury, as well as central pathway
diseases. Information derived from electrophysiological
and psychophysical tests are useful
for identifying loss of smell, but not for discriminating
between central and peripheral
deficits. This is because conventional imaging
modalities are unable to deliver information
about functional olfactory performance. Although
functional imaging is able to show abnormal
changes in central olfactory pathways, it
seems that it is only possible to observe such
abnormalities in olfactory cell dysfunction. We
hypothesize that the scanning of peripheral olfactory
systems by radiolabeled odor molecules
may specifically reveal olfactory dysfunction
and may be useful for differentiating peripheral
from central olfactory disorders
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