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Initial Release (initial + release)
Selected AbstractsRearing and release of Homichloda barkeri (Jacoby) (Coleoptera: Chrysomelidae: Alticinae) for the biological control of prickly acacia, Acacia nilotica ssp. indica (Mimosaceae) in AustraliaAUSTRALIAN JOURNAL OF ENTOMOLOGY, Issue 3 2003Catherine J Lockett Abstract Prickly acacia, Acacia nilotica ssp. indica, a major weed of the Mitchell Grass Downs of northern Queensland, has been the target of biological control projects since the 1980s. The striped leaf-feeding beetle, Homichloda barkeri (Coleoptera: Chrysomelidae: Alticinae), was the third insect approved for release for the control of this weed in Australia. However, mass rearing this insect under glasshouse conditions proved to be difficult and time consuming as there were problems associated with low egg-hatching rates and poor larval survival. Eggs in diapause were stimulated to hatch by repeated wetting and drying. Larvae were fed on potted prickly acacia plants in cages. Late-instar larvae were collected and transferred to a mix of sand, peat moss and vermiculite for pupation and adult emergence. Over 10 500 adults were released at 28 sites in north Queensland between November 1996 and December 1999. Initial releases of insects confined to gauze cages resulted in limited adult survival, oviposition and development of first-generation larvae. First-generation larvae were observed at two sites where cages were not used. However, later inspections of release sites, including those made in April and December 2000, April 2001 and late March 2002, failed to find any trace of the insect, which is assumed to have failed to establish. Possible reasons for this failure are discussed. [source] Implementing Spatial Data Analysis Software Tools in RGEOGRAPHICAL ANALYSIS, Issue 1 2006Roger Bivand This article reports on work in progress on the implementation of functions for spatial statistical analysis, in particular of lattice/area data in the R language environment. The underlying spatial weights matrix classes, as well as methods for deriving them from data from commonly used geographical information systems are presented, handled using other contributed R packages. Since the initial release of some functions in 2001, and the release of the spdep package in 2002, experience has been gained in the use of various functions. The topics covered are the ingestion of positional data, exploratory data analysis of positional, attribute, and neighborhood data, and hypothesis testing of autocorrelation for univariate data. It also provides information about community building in using R for analyzing spatial data. [source] Microinjected neutrophils retain the ability to take up bacteriaJOURNAL OF ANATOMY, Issue 5 2002M. M. Bird It is now possible to microinject protein to probe specific biochemical pathways and/or cell functions in small cells such as human neutrophils (Bird et al. J.Anat.198, 2001). We have shown that these cells retain their ability to modify their F-actin cytoskeleton following the microinjection procedure. The principal task of neutrophils is to hunt and kill bacteria by responding to chemotactic gradients which cause them to extend actin rich pseudopodia in the direction of the highest concentration of these molecules. On reaching their target the neutrophils make tight contact with the bacteria and phagocytosis ensues. Here we address the question of whether or not the microinjected cells are still able to maintain their normal phagocytic activities. Human neutrophils maintained in culture for 20 mins were confronted with Staphylococcus aureus (1 × 104 cells/mL) for 5 min and then injected with rat IgG as an exogenous protein that also serves as a marker for injected cells. After 30 min the cells were fixed for fluorescence or confocal microscopy in 3.7% formaldehyde and permeabilised for 5 min (0.2% Triton X-100 in PBS). They were then incubated for 45 min in 2.5 µL FITC-anti rat IgG and 1 µL TRITC-phalloidin (to show the F-actin cytoskeleton), in 996.5 µL of PBS, washed 6 times in PBS and mounted on slides in 5 µL Mowiol containing a grain of antiquench. For TEM cells were fixed in 1.5% glutaraldehyde in cacodylate buffer for 3 min at room temperature and then washed in 0.2 m cacodylate buffer 6 times before incubation with 1 mm NiCl2 and SIGMA fast DAB peroxidase tablets for 30 min. The cells were postfixed in a 2% solution of osmium tetroxide for 30 min, dehydrated through a series of graded ethanols, and embedded and sectioned for TEM. By TEM the injected neutrophils were observed to have taken up bacteria into vacuoles of varying size. At the earliest stages of this process, prior to and immediately following the initial release of granular contents and the initiation of mechanisms to rapidly destroy bacteria, the bacteria fitted more tightly in the vacuoles than at later stages. Injected neutrophils commonly contained several bacteria; more than one bacterium was frequently located within a single vacuole of substantial size. Confocal laser microscopic observations confirmed that cells containing ingested bacteria also contained IgG. Thus injected cells not only survive the microinjection procedure but also retain their ability to take up bacteria and initiate the digestive process. [source] Release of gentamicin from bone regenerative materials: An in vitro studyJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2007M. Teller Abstract Antibiotic loading of bone regenerative materials is a promising way to protect augmentation procedures from infection during the resorption phase of bone substitutes. Especially in the early stage of implantation, it should protect the grafted site against microbiological pathogens. The present study reports the release kinetics of gentamicin after loading from two synthetic bone filling materials. The first, BONITmatrix®, is a biphasic calcium phosphate silica composite obtained by the sol,gel route consisting of 13% silicon dioxide (w/w) and calcium phosphates (hydroxyapatite/,-tricalcium phosphate 60/40 w/w). The second, Synthacer®, is a sintered hydroxyapatite ceramic. Gentamicin was loaded by dipping and by vacuum coating. Release kinetics of the loaded Gentamicin was investigated by fluorescence polarization immunoassay and by staphylococcus aureus assay. By dipping, loading failed for Synthacer, and it was 12.7 mg gentamicin per gram bone substitute for BONITmatrix. By vacuum coating, loading was 11.3 mg gentamicin per gram bone substitute for Synthacer and 7.4 mg gentamicin per gram bone substitute for BONITmatrix. Distinct release kinetics were measured. For Synthacer, a high initial release was followed by a lower protracted release level up to 28 days. For BONITmatrix release was continuous over the investigated 70-day period. The present data suggest that the porosity properties at the nano- and microscopic levels, or the composition are responsible for antibiotic loading and subsequent release. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006 [source] An investigation of the factors controlling the adsorption of protein antigens to anionic PLG microparticlesJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 11 2005James Chesko Abstract This work examines physico-chemical properties influencing protein adsorption to anionic PLG microparticles and demonstrates the ability to bind and release vaccine antigens over a range of loads, pH values, and ionic strengths. Poly(lactide-co-glycolide) microparticles were synthesized by a w/o/w emulsification method in the presence of the anionic surfactant DSS (dioctyl sodium sulfosuccinate). Ovalbumin (OVA), carbonic anhydrase (CAN), lysozyme (LYZ), lactic acid dehydrogenase, bovine serum albumin (BSA), an HIV envelope glyocoprotein, and a Neisseria meningitidis B protein were adsorbed to the PLG microparticles, with binding efficiency, initial release and zeta potentials measured. Protein (antigen) binding to PLG microparticles was influenced by both electrostatic interaction and other mechanisms such as van der Waals forces. The protein binding capacity was directly proportional to the available surface area and may have a practical upper limit imposed by the formation of a complete protein monolayer as suggested by AFM images. The protein affinity for the PLG surface depended strongly on the isoelectric point (pI) and electrostatic forces, but also showed contributions from nonCoulombic interactions. Protein antigens were adsorbed on anionic PLG microparticles with varying degrees of efficiency under different conditions such as pH and ionic strength. Observable changes in zeta potentials and morphology suggest the formation of a surface monolayer. Antigen binding and release occur through a combination of electrostatic and van der Waals interactions occurring at the polymer-solution interface. © 2005 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 94:2510-2519, 2005 [source] An empirical study of rules for well-formed identifiersJOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 4 2007Dawn Lawrie Abstract Readers of programs have two main sources of domain information: identifier names and comments. In order to efficiently maintain source code, it is important that the identifier names (as well as comments) communicate clearly the concepts they represent. Deißenböck and Pizka recently introduced two rules for creating well-formed identifiers: one considers the consistency of identifiers and the other their conciseness. These rules require a mapping from identifiers to the concepts they represent, which may be costly to develop after the initial release of a system. An approach for verifying whether identifiers are well formed without any additional information (e.g., a concept mapping) is developed. Using a pool of 48 million lines of code, experiments with the resulting syntactic rules for well-formed identifiers illustrate that violations of the syntactic pattern exist. Two case studies show that three-quarters of these violations are ,real'. That is, they could be identified using a concept mapping. Three related studies show that programmers tend to use a rather limited vocabulary, that, contrary to many other aspects of system evolution, maintenance does not introduce additional rule violations, and that open and proprietary sources differ in their percentage of violations. Copyright © 2007 John Wiley & Sons, Ltd. [source] The effect of additives on naltrexone hydrochloride release and solvent removal rate from an injectable in situ forming PLGA implantPOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 5 2006Raheleh Bakhshi Abstract Biodegradable in situ forming drug delivery systems for naltrexone release are promising for post-treatment of drug addicts. The effect of two different additives, glycerol and ethyl heptanoate, on the naltrexone hydrochloride release and solvent removal from a poly(DL -lactide-co-glycolide) (PLGA) injectable implant is presented in this article. The experimental results showed that the in vitro initial release of the drug was decreased in the presence of these additives. Ethyl heptanoate was, however, more effective than glycerol and increasing the amount of additives in PLGA solution up to 5% (w/w) resulted in a decrease of initial naltrexone release rate up to 50%. The morphological evaluation of implants using scanning electron microscopy indicated that the additives generated a less porous structure together with a finger-like to sponge-like transition. The solvent removal profiles of injectable implants, which can be well described by thermogravimetric and morphological analysis, were in good agreement with drug release profiles. Copyright © 2006 John Wiley & Sons, Ltd. [source] Performance assessment of next-generation wireless mobile systemsBELL LABS TECHNICAL JOURNAL, Issue 4 2009Krishna Balachandran The deployment of third generation (3G) systems such as Universal Mobile Telecommunications System (UMTS) and code division multiple access (CDMA) 1X is now ubiquitous. Furthermore, several operators have already deployed evolved 3G systems such as high speed packet access (HSPA) and 1× evolution data optimized (1× EV-DO). These 3G and evolved 3G systems are based on spread spectrum technologies. Now the industry has begun to focus on next-generation wireless systems based on orthogonal frequency division multiplexing (OFDM) technology, flat-Internet Protocol (IP) architectures, and advanced multiple input-multiple output (MIMO) capabilities. These next-generation technologies, primarily are: 3rd Generation Partnership Project (3GPP)-based evolved UMTS terrestrial radio access network (EUTRAN), also called Long Term Evolution (LTE); 3rd Generation Partnership Project 2 (3GPP2)-based Ultra Mobile Broadband (UMB); and Institute of Electrical and Electronics Engineers (IEEE) 802. 16e-based Worldwide Interoperability for Microwave Access (WiMAX). These technologies are in the final specifications to initial deployment phases in selected markets. This paper provides an overview and performance analysis of these next-generation technologies based on their initial releases. Additionally, a comparative performance analysis of these technologies is also presented. © 2009 Alcatel-Lucent. [source] | ||||||||||||||||