Does indirect addressing matter?

In the study of random access machines (RAMs) and the complexities associated with their algorithms, the availability of indirect addressing often creates an analysis obstacle. We show that for RAMs equipped with a sufficiently rich set of basic operations, indirect addressing does not increase computational power, and can be simulated either in linear time or on-line in real time. These results pertain to the uniform cost model and, particularly, assume a unit cost variable shift.     

Spray drying conditions for orange juice incorporated with lactic acid bacteria

This work aimed to develop an orange juice powder by spray drying with lactic acid bacteria (Lactobacillus plantarum 299v and Pediococcus acidilactici HA‐6111‐2), testing their survival both during drying and storage (room temperature and 4 °C). Initially, the best conditions for spray drying were chosen to allow the best survival of each LAB: (i) inlet air temperature of 120 °C and (ii) 0.5:2 ratio of the orange juice soluble solids and drying agent added (prebiotics: 10 DE maltodextrin or gum Arabic). Survival of LAB was not affected by drying process, and it was higher when cultures were stored at 4 °C. A slightly higher protection was conferred by 10 DE maltodextrin, in the case of L. plantarum and at 4 °C. Pediococcus acidilactici was more resistant during storage at 4 °C, with logarithmic reductions lower than 1 log‐unit. It was demonstrated that it is possible to produce a functional nondairy product, orange juice powder supplemented with prebiotic compounds, containing viable LAB for at least 7 months, when stored at 4 °C.     

Liquid-liquid extraction of protease from cold-adapted yeast Rhodotorula mucilaginosa L7 using biocompatible and biodegradable aqueous two-phase systems

This work aimed to optimize the extraction of an extracellular protease produced by the cold-adapted yeast Rhodotorula mucilaginosa L7 using aqueous two-phase systems (ATPS) comprising polyethylene glycol (PEG) and sodium citrate or sodium tartrate. First, the biocompatibility of the phase forming agents was assessed. The results obtained with PEG-2000, PEG-4000, and PEG-6000 demonstrated that even at large PEG concentrations (32 wt%) the protease maintains its activity after 3 h of reaction, whereas an increase in salt concentration provokes a gradual decrease in protease stability. Subsequently, the partitioning of the protease in both types of ATPS was assessed, evaluating the effect of temperature, molecular weight, and concentration of PEG on protease purification, using two 2³-full factorial designs. The best partitioning conditions were obtained in PEG-6000/sodium tartrate-based ATPS, at 30ºC (with a yield of 81.09 ± 0.66% and a purification factor of 2.51 ± 0.03). Thus, considering the biodegradable characteristics of the system, the PEG/sodium tartrate ATPS is a viable and economic low-resolution step in protease purification, with a strong potential for future industrial application.     

Effect of dexamethasone on experimental Escherichia coli mastitis in the cow

The effect of intramuscular administration of dexamethasone on milk production and on several clinical and hematologic indicators in cows with experimental Escherichia coli mastitis was studied. Two groups of three cows each were intramammarily inoculated with 20 x 10(5) cfu E. coli 0101 K99 F41 in rear quarters. Immediately after inoculation one groups received 30 mg dexamethasone intramuscularly, whereas the other group was injected similarly with pyrogen-free saline. Fourteen days later milk production losses were markedly less in the dexamethasone-treated group. Dexamethasone treatment reduced local clinical signs of inflammation, significantly increased rectal temperatures, and diminished inhibition of rumen amplitude during the acute phase of infection. Moreover, cows treated with dexamethasone showed diminished neutropenia, more pronounced hypozincemia, and delayed onset in the decrease in plasma iron concentrations. Possible mechanisms by which these changes are accomplished are discussed.     

Triazolinyl-controlled radical polymerization as innovative route to poly(hydroxyethyl methacrylate)

Summary 2,2'-Azoisobutyronitril (AIBN) initiated radical polymerization of trimethylsilyloxyethyl methacrylate (TMS-HEMA) was carried out in N,N-dimethylformamide (DMF) with the triazolinyl radical (T•) as additive. The latter effected a controlled polymerization process at least up to 60 % monomer conversion. The obtained poly(TMS-HEMA) with triazolin endfunctionality was applied to polymerize styrene, resulting in the formation of poly(TMS-HEMA)-block-polystyrene. Received: 22 February 2001/Accepted: 6 March 2001     

Flexibility as a source of value in the production of alternative fuels: The ethanol case

There is typically a high degree of flexibility associated with the production of alternative fuels due to the ability to source from different input raw materials or to produce different output products based on market conditions. In this paper, we consider the particular example of ethanol and seek to quantify the incremental value from flexibility in its production from sugarcane in Brazil. We accomplish this by first jointly modeling the stochastic processes for the prices of the two relevant commodities, sugar (a food commodity) and ethanol (an energy commodity) in discrete time as a bivariate lattice. This framework allows us to value the option to switch output products based on the respective price signals of the two commodities. However, unlike the usual assumption of geometric Brownian motion stochastic processes, we use the more realistic case of mean reverting commodity price processes. We estimate the parameters for these processes by applying a regression-based procedure to empirical sugar and ethanol data collected during a period from 1998 through 2008. Our results show that the option to switch outputs has significant value, even under the assumption of mean reverting prices, which has implications for both producers and policy-makers alike.     

Term Rewriting with Type-safe Traversal Functions

Term rewriting is an appealing technique for performing program analysis and program transformation. Tree (term) traversal is frequently used but is not supported by standard term rewriting. In this paper, many-sorted first-order term rewriting is extended with automatic tree traversal by adding two primitive tree traversal strategies and complementing them with three types of traversals. These so-called traversal functions can be either top-down or bottom-up. They can be sort preserving, mapping to a single sort, or a combination of these two. Traversal functions have a simple design, their application is type-safe in a first-order many-sorted setting and can be implemented efficiently. We describe the operational semantics of traversal functions and discuss applications.     

Mammalian Exocrine Secretions. XII: Constituents of Interdigital Secretions of Bontebok, Damaliscus dorcas dorcas, and Blesbok, D. d. phillipsi

In addition to the nine compounds identified in the interdigital secretion of the bontebok, Damaliscus dorcas dorcas, in a previous study, 76 compounds belonging to different compound types, were identified in the interdigital secretions of the bontebok and the blesbok, D. d. phillipsi. These compounds include alkanes, alcohols, aldehydes, ketones, fatty acids, terpenoids, -lactones, an isopropyl ester, long-chain hydroxyesters, 2-substituted pyridines, phenols, steroids, and dimethylsulfone. No qualitative differences were found between secretions from the two sexes or from animals from different habitats. Although no attempt was made to correlate territorial behavior or other behavioral phenomena with the qualitative composition of interdigital secretions from individual animals, available information seems to indicate that quantitative differences probably do not have a major semiochemical function. Only two species of bacteria, Bacillus brevis and Planococcus citreus, were found in the interdigital pouches of male and female members of the two subspecies, regardless of the habitat of the animals. B. brevis synthesized, among other unidentified constituents, (Z)-3-penten-2-ol, 2-hexanone, 2-octanone, 2-nonanone, tetradecanoic acid, pentadecanoic acid, heptadecanoic acid, octadecanoic acid, (Z)-9-hexadecenoic acid, and isopropyl hexadecanoate in vitro, while P. citreus produced, among others, the -lactones dodecan-4-olide and (Z)-6-dodecen-4-olide, which is one of the major constituents of the interdigital secretions of both subspecies. Some components of the interdigital secretions are not present in the interdigital glandular tissue, and the possibility is discused that these compounds could be produced by microbiological activity in the interdigital pouch.