13 resultados para product standards

em Helda - Digital Repository of University of Helsinki


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Drug Analysis without Primary Reference Standards: Application of LC-TOFMS and LC-CLND to Biofluids and Seized Material Primary reference standards for new drugs, metabolites, designer drugs or rare substances may not be obtainable within a reasonable period of time or their availability may also be hindered by extensive administrative requirements. Standards are usually costly and may have a limited shelf life. Finally, many compounds are not available commercially and sometimes not at all. A new approach within forensic and clinical drug analysis involves substance identification based on accurate mass measurement by liquid chromatography coupled with time-of-flight mass spectrometry (LC-TOFMS) and quantification by LC coupled with chemiluminescence nitrogen detection (LC-CLND) possessing equimolar response to nitrogen. Formula-based identification relies on the fact that the accurate mass of an ion from a chemical compound corresponds to the elemental composition of that compound. Single-calibrant nitrogen based quantification is feasible with a nitrogen-specific detector since approximately 90% of drugs contain nitrogen. A method was developed for toxicological drug screening in 1 ml urine samples by LC-TOFMS. A large target database of exact monoisotopic masses was constructed, representing the elemental formulae of reference drugs and their metabolites. Identification was based on matching the sample component s measured parameters with those in the database, including accurate mass and retention time, if available. In addition, an algorithm for isotopic pattern match (SigmaFit) was applied. Differences in ion abundance in urine extracts did not affect the mass accuracy or the SigmaFit values. For routine screening practice, a mass tolerance of 10 ppm and a SigmaFit tolerance of 0.03 were established. Seized street drug samples were analysed instantly by LC-TOFMS and LC-CLND, using a dilute and shoot approach. In the quantitative analysis of amphetamine, heroin and cocaine findings, the mean relative difference between the results of LC-CLND and the reference methods was only 11%. In blood specimens, liquid-liquid extraction recoveries for basic lipophilic drugs were first established and the validity of the generic extraction recovery-corrected single-calibrant LC-CLND was then verified with proficiency test samples. The mean accuracy was 24% and 17% for plasma and whole blood samples, respectively, all results falling within the confidence range of the reference concentrations. Further, metabolic ratios for the opioid drug tramadol were determined in a pharmacogenetic study setting. Extraction recovery estimation, based on model compounds with similar physicochemical characteristics, produced clinically feasible results without reference standards.

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Layering is a widely used method for structuring data in CAD-models. During the last few years national standardisation organisations, professional associations, user groups for particular CAD-systems, individual companies etc. have issued numerous standards and guidelines for the naming and structuring of layers in building design. In order to increase the integration of CAD data in the industry as a whole ISO recently decided to define an international standard for layer usage. The resulting standard proposal, ISO 13567, is a rather complex framework standard which strives to be more of a union than the least common denominator of the capabilities of existing guidelines. A number of principles have been followed in the design of the proposal. The first one is the separation of the conceptual organisation of information (semantics) from the way this information is coded (syntax). The second one is orthogonality - the fact that many ways of classifying information are independent of each other and can be applied in combinations. The third overriding principle is the reuse of existing national or international standards whenever appropriate. The fourth principle allows users to apply well-defined subsets of the overall superset of possible layernames. This article describes the semantic organisation of the standard proposal as well as its default syntax. Important information categories deal with the party responsible for the information, the type of building element shown, whether a layer contains the direct graphical description of a building part or additional information needed in an output drawing etc. Non-mandatory information categories facilitate the structuring of information in rebuilding projects, use of layers for spatial grouping in large multi-storey projects, and storing multiple representations intended for different drawing scales in the same model. Pilot testing of ISO 13567 is currently being carried out in a number of countries which have been involved in the definition of the standard. In the article two implementations, which have been carried out independently in Sweden and Finland, are described. The article concludes with a discussion of the benefits and possible drawbacks of the standard. Incremental development within the industry, (where ”best practice” can become ”common practice” via a standard such as ISO 13567), is contrasted with the more idealistic scenario of building product models. The relationship between CAD-layering, document management product modelling and building element classification is also discussed.

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One of the central issues in making efficient use of IT in the design, construction and maintenance of buildings is the sharing of the digital building data across disciplines and lifecycle stages. One technology which enables data sharing is CAD layering, which to be of real use requires the definition of standards. This paper focuses on the background, objectives and effectiveness of the International standard ISO 13567, Organisation and naming of layers for CAD. In particular the efficiency and effectiveness of the standardisation and standard implementation process are in focus, rather than the technical details. The study was conducted as a qualitative study with a number of experts who responded to a semi-structured mail questionnaire, supplemented by personal interviews. The main results were that CAD layer standards based on the ISO standard have been implemented, particularly in northern European countries, but are not very widely used. A major problem which was identified was the lack of resources for marketing and implementing the standard as national variations, once it had been formally accepted.

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There has been a demand for uniform CAD standards in the construction industry ever since the large-scale introduction of computer aided design systems in the late 1980s. While some standards have been widely adopted without much formal effort, other standards have failed to gain support even though considerable resources have been allocated for the purpose. Establishing a standard concerning building information modeling has been one particularly active area of industry development and scientific interest within recent years. In this paper, four different standards are discussed as cases: the IGES and DXF/DWG standards for representing the graphics in 2D drawings, the ISO 13567 standard for the structuring of building information on layers, and the IFC standard for building product models. Based on a literature study combined with two qualitative interview studies with domain experts, a process model is proposed to describe and interpret the contrasting histories of past CAD standardisation processes.

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We all have fresh in our memory what happened to the IT sector only a few years ago when the IT-bubble burst. The upswing of productivity in this sector slowed down, investors lost large investments, many found themselves looking for a new job, and countless dreams fell apart. Product developers in the IT sector have experienced a large number of organizational restructurings since the IT boom, including rapid growth, downsizing processes, and structural reforms. Organizational restructurings seem to be a complex and continuous phenomenon people in this sector have to deal with. How do software product developers retrospectively construct their work in relation to organizational restructurings? How do organizational restructurings bring about specific social processes in product development? This working paper focuses on these questions. The overall aim is to develop an understanding of how software product developers construct their work during organizational restructurings. The theoretical frame of reference is based on a social constructionist approach and discourse analysis. This approach offers more or less radical and critical alternatives to mainstream organizational theory. Writings from this perspective attempt to investigate and understand sociocultural processes by which various realities are created. Therefore these studies aim at showing how people participate in constituting the social world (Gergen & Thatchenkery, 1996); knowledge of the world is seen to be constructed between people in daily interaction, in which language plays a central role. This means that interaction, especially the ways of talking and writing about product development during organizational restructurings, become the target of concern. This study consists of 25 in-depth interviews following a pilot study based on 57 semi-structured interviews. In this working paper I analyze 9 in-depth interviews. The interviews were conducted in eight IT firms. The analysis explores how discourses are constructed and function, as well as the consequences that follow from different discourses. The analysis shows that even though the product developers have experienced many organizational restructurings, some of which have been far-reaching, their accounts build strongly on a stability discourse. According to this discourse product development is, perhaps surprisingly, not influenced to a great extent by organizational restructurings. This does not mean that product development is static. According to the social constructionist approach, product development is constantly being reproduced and maintained in ongoing processes. In other words stable effects are also ongoing achievements and these are of particular interest in this study. The product developers maintain rather than change the product development through ongoing processes of construction, even when they experience continuous extensive organizational restructurings. The discourse of stability exists alongside other discourses, some which contradict each other. Together they direct product development and generate meanings. The product developers consequently take an active role in the construction of their work during organizational restructurings. When doing this they also negotiate credible positions for themselves

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The first line medication for mild to moderate Alzheimer s disease (AD) is based on cholinesterase inhibitors which prolong the effect of the neurotransmitter acetylcholine in cholinergic nerve synapses which relieves the symptoms of the disease. Implications of cholinesterases involvement in disease modifying processes has increased interest in this research area. The drug discovery and development process is a long and expensive process that takes on average 13.5 years and costs approximately 0.9 billion US dollars. Drug attritions in the clinical phases are common due to several reasons, e.g., poor bioavailability of compounds leading to low efficacy or toxic effects. Thus, improvements in the early drug discovery process are needed to create highly potent non-toxic compounds with predicted drug-like properties. Nature has been a good source for the discovery of new medicines accounting for around half of the new drugs approved to market during the last three decades. These compounds are direct isolates from the nature, their synthetic derivatives or natural mimics. Synthetic chemistry is an alternative way to produce compounds for drug discovery purposes. Both sources have pros and cons. The screening of new bioactive compounds in vitro is based on assaying compound libraries against targets. Assay set-up has to be adapted and validated for each screen to produce high quality data. Depending on the size of the library, miniaturization and automation are often requirements to reduce solvent and compound amounts and fasten the process. In this contribution, natural extract, natural pure compound and synthetic compound libraries were assessed as sources for new bioactive compounds. The libraries were screened primarily for acetylcholinesterase inhibitory effect and secondarily for butyrylcholinesterase inhibitory effect. To be able to screen the libraries, two assays were evaluated as screening tools and adapted to be compatible with special features of each library. The assays were validated to create high quality data. Cholinesterase inhibitors with various potencies and selectivity were found in natural product and synthetic compound libraries which indicates that the two sources complement each other. It is acknowledged that natural compounds differ structurally from compounds in synthetic compound libraries which further support the view of complementation especially if a high diversity of structures is the criterion for selection of compounds in a library.

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Many Finnish IT companies have gone through numerous organizational changes over the past decades. This book draws attention to how stability may be central to software product development experts and IT workers more generally, who continuously have to cope with such change in their workplaces. It does so by analyzing and theorizing change and stability as intertwined and co-existent, thus throwing light on how it is possible that, for example, even if ‘the walls fall down the blokes just code’ and maintain a sense of stability in their daily work. Rather than reproducing the picture of software product development as exciting cutting edge activities and organizational change as dramatic episodes, the study takes the reader beyond the myths surrounding these phenomena to the mundane practices, routines and organizings in product development during organizational change. An analysis of these ordinary practices offers insights into how software product development experts actively engage in constructing stability during organizational change through a variety of practices, including solidarity, homosociality, close relations to products, instrumental or functional views on products, preoccupations with certain tasks and humble obedience. Consequently, the study shows that it may be more appropriate to talk about varieties of stability, characterized by a multitude of practices of stabilizing rather than states of stagnation. Looking at different practices of stability in depth shows the creation of software as an arena for micro-politics, power relations and increasing pressures for order and formalization. The thesis gives particular attention to power relations and processes of positioning following organizational change: how social actors come to understand themselves in the context of ongoing organizational change, how they comply with and/or contest dominant meanings, how they identify and dis-identify with formalization, and how power relations often are reproduced despite dis-identification. Related to processes of positioning, the reader is also given a glimpse into what being at work in a male-dominated and relatively homogeneous work environment looks like. It shows how the strong presence of men or “blokes” of a particular age and education seems to become invisible in workplace talk that appears ‘non-conscious’ of gender.

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Merkittävä osa alkuperäislääkevalmistajien tutkimus- ja tuotekehityskuluista näyttää olevan suunnattu olemassa olevien lääkkeiden kehittämiseen. Tämä voi oletettavasti johtaa kiinnostaviin formulaatiokehitysstrategioihin. Tutkimuksen tarkoituksena oli selvittää, voidaanko farmaseuttisen tuotekehityksen trendejä havaita myönnettyjen myyntilupien perusteella. Tutkimuksen mielenkiinnon kohteena olivat myös suurimpien lääkeyritysten käyttämät elinkaaren hallinnan keinot, joilla suojataan myyvimpiä tuotteita geneeriseltä kilpailulta ja varmistetaan markkinaosuus. Tutkimuksen painopiste oli kiinteissä oraalisissa lääkevalmisteissa. Laadullisten ja määrällisten menetelmien yhdistelmää käytettiin laajan näkökulman saamiseksi tutkittavaan aiheeseen. Suomalaisten myyntilupaviranomaisten haastatteluja käytettiin keräämään taustatietoa tutkimuksen määrällistä osaa varten. Määrällinen osa koostui myyntilupatietokannoista, jotka käsittivät kaikkien menettelyjen kautta Suomessa myönnetyt myyntiluvat, keskitetyn menettelyn kautta EU:ssa myönnetyt myyntiluvat ja maailman kymmenen suurinta lääkeyritystä USA:ssa. Tutkimustulosten perusteella rinnakkaislääkkeiden määrässä tapahtui merkittävä nousu Suomessa kaikkien menettelyjen kautta myönnetyissä myyntiluvissa ja EU:ssa keskitetyn menettelyn kautta myönnetyissä myyntiluvissa vuosina 2000-2010. Tämä muutos saattaa ainakin osaksi johtua lainsäädännöllisistä muutoksista, joilla luotiin kannustimia rinnakkaislääkkeiden käyttöön ja valmistukseen, kuten lääkevaihto ja viitehintajärjestelmä. USA:n tiedot osoittivat suurten lääkevalmistajien kiinnostuksen elinkaaren hallintaan: suurin osa maailman kymmenelle suurimmalle lääkeyritykselle myönnetyistä myyntiluvista vuosina 2005-2010 oli tähän tarkoitukseen. Elinkaaren hallinnan suhde uusiin lääkeaineisiin oli lähes 4:1. Kiinteä oraalinen lääkemuoto on kiistatta kaikista suosituin tapa annostella lääke, minkä vahvistivat sekä arvioijien haastattelut että myyntilupatiedot. Kiinteiden oraalisten rooli oli entistäkin korostuneempi rinnakkaislääkkeiden kohdalla. Kun innovatiivisuutta mitattiin epätyypillisten annosmuotojen määrällä, USA:n tiedot kiinteistä oraalisista lääkemuodoista osoittivat vahvaa innovatiivisuutta Suomen ja EU:n tietoihin verrattuna. Tämä saattaa heijastaa suurten lääkeyritysten innovatiivista tuotevalikoimaa. Epätyypillisten kiinteiden oraalisten annosmuotojen osuus oli huomattavasti pienempi rinnakkaislääkkeissä kuin alkuperäislääkkeissä kaikilla alueilla. Elinkaaren hallinnassa käytetyimmät strategiat olivat uusi formulaatio, uusi vahvuus ja uusi yhdistelmä olemassa olevasta valmisteesta. Kiinteiden oraalisten lääkemuotojen osalta kaksi kolmasosaa uusista elinkaaren hallinnan formulaatioista oli säädellysti vapauttavia valmisteita. Elinkaaren hallinta on olennainen osa suurten lääkeyritysten liiketoimintastrategiaa, ja sen tärkeyttä havainnollistettiin Coreg-tablettien tapausesimerkillä.

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Generation of raw materials for dry powder inhalers by different size reduction methods can be expected to influence physical and chemical properties of the powders. This can cause differences in particle size, size distribution, shape, crystalline properties, surface texture and energy. These physical properties of powders influence the behaviour of particles before and after inhalation. Materials with an amorphous surface have different surface energy compared to materials with crystalline surface. This can affect the adhesion and cohesion of particles. Changes in the surface nature of the drug particles results in a change in product performance. By stabilization of the raw materials the amorphous surfaces are converted into crystalline surfaces. The primary aim of the study was to investigate the influence of the surface properties of the inhalation particles on the quality of the product. The quality of the inhalation product is evaluated by measuring the fine particle dose (FPD). FDP is the total dose of particles with aerodynamic diameters smaller than 5,0 μm. The secondary aim of this study was to achieve the target level of the FPD and the stability of the FPD. This study was also used to evaluate the importance of the stabilization of the inhalation powders. The study included manufacturing and analysing drug substance 200 μg/dose inhalation powder batches using non-stabilized or stabilized raw materials. The inhaler formulation consisted of micronized drug substance, lactose <100μm and micronized lactose <10μm. The inhaler device was Easyhaler®. Stabilization of the raw materials was done in different relative humidity, temperature and time. Surface properties of the raw materials were studied by dynamic vapour sorption, scanning electron microscopy and three-point nitrogen adsorption technique. Particle size was studied by laser diffraction particle size analyzer. Aerodynamic particle size distribution from inhalers was measured by new generation impactor. Stabilization of all three raw materials was successful. A clear difference between nonstabilized and stabilized raw materials was achieved for drug substance and lactose <10μm. However for lactose <100μm the difference wasn’t as clear as wanted. The surface of the non-stabilized drug substance was more irregular and the particles had more roughness on the surface compared to the stabilized drug substances particles surface. The surface of the stabilized drug particles was more regular and smoother than non-stabilized. Even though a good difference between stabilized and non-stabilized raw materials was achieved, a clear evidence of the effect of the surface properties of the inhalation particles on the quality of the product was not observed. Stabilization of the raw materials didn’t lead to a higher FPD. Possible explanations for the unexpected result might be too rough conditions in the stabilization of the drug substance or smaller than wanted difference in the degree of stabilization of the main component of the product <100μm. Despite positive effects on the quality of the product were not seen there appears to be some evidence that stabilized drug substance results in smaller particle size of dry powder inhalers.