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Analysis and design of modern stream ciphers

When designing symmetric ciphers, security and performance are of utmost importance. When selecting a symmetric encryption algorithm, the first choice is whether to choose a block cipher or a stream cipher. Most modern block ciphers offer a sufficient security and a reasonably good performance. But a block cipher must usually be used in a stream cipher mode of operation, which suggests that using

Comparison of food frequency questionnaires: the reduced Block and Willett questionnaires differ in ranking on nutrient intakes

Food frequency questionnaires, major tools in epidemiologic studies, are often criticized for biased and imprecise intake estimates. The aim of this study was to compare the performance of two widely used food frequency questionnaires, a reduced 60-item Block questionnaire and a 153-item Willett food frequency questionnaire, relative to three 24-hour recalls administered by telephone. The dietary

Mediator-modified electrodes for catalytic NADH oxidation: high rate constants at interesting overpotentials.

Carbon paste electrodes were modified with a nitrofluorenone derivative, 2,4,7-trinitro-9-fluorenone, adsorbed on zirconium phosphate (ZP). After electrochemical reduction of the fluorenone derivative, it turns into a very efficient mediator for electrocatalytic NADH oxidation, with a formal potential of about +250 mV vs. Ag/AgCl. The electrochemistry and the electrocatalytic properties of the med

Rat intestinal ceramidase: purification, properties and physiological relevance.

Neutral ceramidase activity has previously been identified in the intestinal mucosa and gut lumen and postulated to be important in the digestion of sphingolipids. It is found throughout the intestine but has never been fully characterized. We have purified rat intestinal neutral ceramidase from an eluate obtained by perfusing the intestinal lumen with 0.9% NaCl and 3 mM sodium taurodeoxycholate.

Operating charts for continuous sedimentation III: control of step inputs

The main purposes of a clarifier-thickener unit is that it should produce a high underflow concentration and a zero effluent concentration. The main difficulty in the control of the clarification-thickening process (by adjusting a volume flow) is that it is nonlinear with complex relations between concentrations and volume flows via the solution of a PDE - a conservation law with a source term and

Prognostic impact of tumour-specific HMG-CoA reductase expression in primary breast cancer

Introduction We have previously reported that tumour-specific expression of the rate-limiting enzyme, 3-hydroxy-3-methylglutharyl-coenzyme A reductase (HMG-CoAR), in the mevalonate pathway is associated with more favourable tumour parameters in breast cancer. In the present study, we examined the prognostic value of HMG-CoAR expression in a large cohort of primary breast cancer patients with long-

The development of global consensus guidelines on the management of the diabetic foot

The future for diabetes is grave. Now described as the global epidemic of the 21st century, the increasing incidence of diabetes (in 2007 over 246 million people affected by diabetes) will place considerable strain on resources and will bring suffering to many if the preventative measures promoted by the International Diabetes Federation (IDF), the International Working Group on the Diabetic Foot

Voluntary Environmental Reporting in Romania

Abstract in UndeterminedToday, thousands of leading companies issue voluntary environmental, CSR or sustainability reports with Europe holding more than 50 per cent of all reports published world-wide. It seems like voluntary reporting is here to stay for the time being. In contrast to the development and implementation of such practices in Western Europe, we do not have much knowledge about the s

Antiatherosclerotic effects of beta-blockers

Accumulating data from studies in animals and humans indicate that beta-blockade has antiatherosclerotic effects. To date, 2 long-term ultrasound studies provide the strongest evidence. The Beta-Blocker Cholesterol-Lowering Asymptomatic Plaque Study (BCAPS) trial reported favorable effects with beta-blockade on early stages of atherosclerosis in patients with carotid plaque but no symptoms of caro

Direct electron transfer - A favorite electron route for cellobiose dehydrogenase (CDH) from Trametes villosa. Comparison with CDH from Phanerochaete chrysosporium

This paper presents some functional differences as well as similarities observed when comparing the newly discovered cellobiose dehydrogenase (CDH) from Trametes Villosa (T.v) with the well-characterized one from Phanerochaete chrysosporium (P.c.). The enzymes were physically adsorbed on spectrographic graphite electrodes placed in an amperometric flow through cell connected to a flow system. In t

Long-term preservation of vascular endothelium and smooth muscle

This study was performed in organ baths on 400 ring segments of infrarenal aorta taken from 40 Sprague-Dawley rats that had been randomized into five groups. Contractility was tested with the thromboxane analogue U-46619. Acetylcholine was used to elicit endothelium-dependent relaxing factor (EDRF). The results obtained from vessels preserved at 4 degrees C for 6, 12, 24, and 36 hours were compare

Decrease in the occurrence of ventricular fibrillation as the initially observed arrhythmia after out-of-hospital cardiac arrest during 11 years in Sweden

Aim: To describe the change in the occurrence of ventricular fibrillation as initially observed arrhythmia among patients suffering from out-of-hospital cardiac arrest in Sweden. Patients: All patients included in the Swedish cardiac arrest registry between 1991 until 2001. The registry covers 85% of the population in Sweden. Methods: All patients with bystander witnessed out-of-hospital cardiac a

Molecular recognition in the protein C anticoagulant pathway.

The protein C (PC) anticoagulant system provides specific and efficient control of blood coagulation. The system comprises circulating or membrane-bound protein components that take part in complicated multimolecular protein complexes being assembled on specific cellular phospholipid membranes. Each of the participating proteins is composed of multiple domains, many of which are known at the level

An allozyme study of sexual and vegetative regeneration in Hieracium pilosella L.

Abstract in French Afin d’évaluer l’importance relative de la reproduction sexuelle et végétative dans les populations d’une plante de prairie, l’Hieracium pilosella L., les auteurs ont utilisé des marqueurs allozymiques permettant d’en identifier les clones. Les études conduites aux champs, sur les populations d’espèces de plantes clonales, ont souvent fait état de recrutement absent ou négligeabAllozyme markers were used to fingerprint clones of the grassland plant Hieracium pilosella and, by inference, to estimate the relative importance of sexual and vegetative reproduction in a population. Field studies in populations of clonal plant species have often reported negligible or absent recruitment from seed. In contrast, studies of genetic markers have found substantial clonal diversity i

Self-administered questionnaire compared with a personal diary for assessment of current use of hormone therapy: an analysis of 16,060 women

A personal diary may be more appropriate than a questionnaire for assessing self-reported current use of hormone therapy (estrogens, progestagens, or their combination); however, use of a questionnaire is more feasible and less expensive. The authors compared both methods for 16,060 Swedish women aged 45-73 years from the Malmo Diet and Cancer Study (baseline, 1991-1996). In a reliability analysis

Inflammatory cell response in bronchoalveolar lavage fluid after nitrogen dioxide exposure of healthy subjects: a dose-response study

The combination of environmental chamber exposure and bronchoalveolar lavage (BAL) was used to study the effects of the common air pollutant nitrogen dioxide (NO2). Eighteen healthy nonsmokers were exposed to NO2 during 20 min in an exposure chamber during light bicycle ergometer work. All subjects were examined with BAL at least 3 wks before exposure, as a reference. The subjects were re-examined

Gene expression profilers and conventional clinical markers to predict distant recurrences for premenopausal breast cancer patients after adjuvant chemotherapy.

A large proportion of breast cancer patients are treated with adjuvant chemotherapy after the primary operation, but some will recur in spite of this treatment. In order to achieve an improved and more individualised therapy, our knowledge in mechanisms for drug resistance needs to be increased. We have investigated to what extent cDNA microarray measurements could distinguish the likelihood of re

Diffusion of polyethyleneglycols in casein solutions and gels as studied by pulsed field gradient NMR

Molecular transport characterized by diffusion coefficients is a key feature of food processes and especially in dairy processes. Caseins represent 80% of the protein content in milk and are directly involved in the formation of dairy gels. Consequently, providing a quantitative description of the solute diffusion in casein gels should contribute significantly to rationalization of the dairy proce