Assessing the added value of wastewater-based epidemiology to monitor illicit drug use

Wastewater-based epidemiology consists in acquiring relevant information about the lifestyle and health status of the population through the analysis of wastewater samples collected at the influent of a wastewater treatment plant. Whilst being a very young discipline, it has experienced an astonishing development since its firs application in 2005. The possibility to gather community-wide information about drug use has been among the major field of application. The wide resonance of the first results sparked the interest of scientists from various disciplines. Since then, research has broadened in innumerable directions. Although being praised as a revolutionary approach, there was a need to critically assess its added value, with regard to the existing indicators used to monitor illicit drug use. The main, and explicit, objective of this research was to evaluate the added value of wastewater-based epidemiology with regards to two particular, although interconnected, dimensions of illicit drug use. The first is related to trying to understand the added value of the discipline from an epidemiological, or societal, perspective. In other terms, to evaluate if and how it completes our current vision about the extent of illicit drug use at the population level, and if it can guide the planning of future prevention measures and drug policies. The second dimension is the criminal one, with a particular focus on the networks which develop around the large demand in illicit drugs. The goal here was to assess if wastewater-based epidemiology, combined to indicators stemming from the epidemiological dimension, could provide additional clues about the structure of drug distribution networks and the size of their market. This research had also an implicit objective, which focused on initiating the path of wastewater- based epidemiology at the Ecole des Sciences Criminelles of the University of Lausanne. This consisted in gathering the necessary knowledge about the collection, preparation, and analysis of wastewater samples and, most importantly, to understand how to interpret the acquired data and produce useful information. In the first phase of this research, it was possible to determine that ammonium loads, measured directly in the wastewater stream, could be used to monitor the dynamics of the population served by the wastewater treatment plant. Furthermore, it was shown that on the long term, the population did not have a substantial impact on consumption patterns measured through wastewater analysis. Focussing on methadone, for which precise prescription data was available, it was possible to show that reliable consumption estimates could be obtained via wastewater analysis. This allowed to validate the selected sampling strategy, which was then used to monitor the consumption of heroin, through the measurement of morphine. The latter, in combination to prescription and sales data, provided estimates of heroin consumption in line with other indicators. These results, combined to epidemiological data, highlighted the good correspondence between measurements and expectations and, furthermore, suggested that the dark figure of heroin users evading harm-reduction programs, which would thus not be measured by conventional indicators, is likely limited. In the third part, which consisted in a collaborative study aiming at extensively investigating geographical differences in drug use, wastewater analysis was shown to be a useful complement to existing indicators. In particular for stigmatised drugs, such as cocaine and heroin, it allowed to decipher the complex picture derived from surveys and crime statistics. Globally, it provided relevant information to better understand the drug market, both from an epidemiological and repressive perspective. The fourth part focused on cannabis and on the potential of combining wastewater and survey data to overcome some of their respective limitations. Using a hierarchical inference model, it was possible to refine current estimates of cannabis prevalence in the metropolitan area of Lausanne. Wastewater results suggested that the actual prevalence is substantially higher compared to existing figures, thus supporting the common belief that surveys tend to underestimate cannabis use. Whilst being affected by several biases, the information collected through surveys allowed to overcome some of the limitations linked to the analysis of cannabis markers in wastewater (i.e., stability and limited excretion data). These findings highlighted the importance and utility of combining wastewater-based epidemiology to existing indicators about drug use. Similarly, the fifth part of the research was centred on assessing the potential uses of wastewater-based epidemiology from a law enforcement perspective. Through three concrete examples, it was shown that results from wastewater analysis can be used to produce highly relevant intelligence, allowing drug enforcement to assess the structure and operations of drug distribution networks and, ultimately, guide their decisions at the tactical and/or operational level. Finally, the potential to implement wastewater-based epidemiology to monitor the use of harmful, prohibited and counterfeit pharmaceuticals was illustrated through the analysis of sibutramine, and its urinary metabolite, in wastewater samples. The results of this research have highlighted that wastewater-based epidemiology is a useful and powerful approach with numerous scopes. Faced with the complexity of measuring a hidden phenomenon like illicit drug use, it is a major addition to the panoply of existing indicators. -- L'épidémiologie basée sur l'analyse des eaux usées (ou, selon sa définition anglaise, « wastewater-based epidemiology ») consiste en l'acquisition d'informations portant sur le mode de vie et l'état de santé d'une population via l'analyse d'échantillons d'eaux usées récoltés à l'entrée des stations d'épuration. Bien qu'il s'agisse d'une discipline récente, elle a vécu des développements importants depuis sa première mise en oeuvre en 2005, notamment dans le domaine de l'analyse des résidus de stupéfiants. Suite aux retombées médiatiques des premiers résultats de ces analyses de métabolites dans les eaux usées, de nombreux scientifiques provenant de différentes disciplines ont rejoint les rangs de cette nouvelle discipline en développant plusieurs axes de recherche distincts. Bien que reconnu pour son coté objectif et révolutionnaire, il était nécessaire d'évaluer sa valeur ajoutée en regard des indicateurs couramment utilisés pour mesurer la consommation de stupéfiants. En se focalisant sur deux dimensions spécifiques de la consommation de stupéfiants, l'objectif principal de cette recherche était focalisé sur l'évaluation de la valeur ajoutée de l'épidémiologie basée sur l'analyse des eaux usées. La première dimension abordée était celle épidémiologique ou sociétale. En d'autres termes, il s'agissait de comprendre si et comment l'analyse des eaux usées permettait de compléter la vision actuelle sur la problématique, ainsi que déterminer son utilité dans la planification des mesures préventives et des politiques en matière de stupéfiants actuelles et futures. La seconde dimension abordée était celle criminelle, en particulier, l'étude des réseaux qui se développent autour du trafic de produits stupéfiants. L'objectif était de déterminer si cette nouvelle approche combinée aux indicateurs conventionnels, fournissait de nouveaux indices quant à la structure et l'organisation des réseaux de distribution ainsi que sur les dimensions du marché. Cette recherche avait aussi un objectif implicite, développer et d'évaluer la mise en place de l'épidémiologie basée sur l'analyse des eaux usées. En particulier, il s'agissait d'acquérir les connaissances nécessaires quant à la manière de collecter, traiter et analyser des échantillons d'eaux usées, mais surtout, de comprendre comment interpréter les données afin d'en extraire les informations les plus pertinentes. Dans la première phase de cette recherche, il y pu être mis en évidence que les charges en ammonium, mesurées directement dans les eaux usées permettait de suivre la dynamique des mouvements de la population contributrice aux eaux usées de la station d'épuration de la zone étudiée. De plus, il a pu être démontré que, sur le long terme, les mouvements de la population n'avaient pas d'influence substantielle sur le pattern de consommation mesuré dans les eaux usées. En se focalisant sur la méthadone, une substance pour laquelle des données précises sur le nombre de prescriptions étaient disponibles, il a pu être démontré que des estimations exactes sur la consommation pouvaient être tirées de l'analyse des eaux usées. Ceci a permis de valider la stratégie d'échantillonnage adoptée, qui, par le bais de la morphine, a ensuite été utilisée pour suivre la consommation d'héroïne. Combinée aux données de vente et de prescription, l'analyse de la morphine a permis d'obtenir des estimations sur la consommation d'héroïne en accord avec des indicateurs conventionnels. Ces résultats, combinés aux données épidémiologiques ont permis de montrer une bonne adéquation entre les projections des deux approches et ainsi démontrer que le chiffre noir des consommateurs qui échappent aux mesures de réduction de risque, et qui ne seraient donc pas mesurés par ces indicateurs, est vraisemblablement limité. La troisième partie du travail a été réalisée dans le cadre d'une étude collaborative qui avait pour but d'investiguer la valeur ajoutée de l'analyse des eaux usées à mettre en évidence des différences géographiques dans la consommation de stupéfiants. En particulier pour des substances stigmatisées, telles la cocaïne et l'héroïne, l'approche a permis d'objectiver et de préciser la vision obtenue avec les indicateurs traditionnels du type sondages ou les statistiques policières. Globalement, l'analyse des eaux usées s'est montrée être un outil très utile pour mieux comprendre le marché des stupéfiants, à la fois sous l'angle épidémiologique et répressif. La quatrième partie du travail était focalisée sur la problématique du cannabis ainsi que sur le potentiel de combiner l'analyse des eaux usées aux données de sondage afin de surmonter, en partie, leurs limitations. En utilisant un modèle d'inférence hiérarchique, il a été possible d'affiner les actuelles estimations sur la prévalence de l'utilisation de cannabis dans la zone métropolitaine de la ville de Lausanne. Les résultats ont démontré que celle-ci est plus haute que ce que l'on s'attendait, confirmant ainsi l'hypothèse que les sondages ont tendance à sous-estimer la consommation de cannabis. Bien que biaisés, les données récoltées par les sondages ont permis de surmonter certaines des limitations liées à l'analyse des marqueurs du cannabis dans les eaux usées (i.e., stabilité et manque de données sur l'excrétion). Ces résultats mettent en évidence l'importance et l'utilité de combiner les résultats de l'analyse des eaux usées aux indicateurs existants. De la même façon, la cinquième partie du travail était centrée sur l'apport de l'analyse des eaux usées du point de vue de la police. Au travers de trois exemples, l'utilisation de l'indicateur pour produire du renseignement concernant la structure et les activités des réseaux de distribution de stupéfiants, ainsi que pour guider les choix stratégiques et opérationnels de la police, a été mise en évidence. Dans la dernière partie, la possibilité d'utiliser cette approche pour suivre la consommation de produits pharmaceutiques dangereux, interdits ou contrefaits, a été démontrée par l'analyse dans les eaux usées de la sibutramine et ses métabolites. Les résultats de cette recherche ont mis en évidence que l'épidémiologie par l'analyse des eaux usées est une approche pertinente et puissante, ayant de nombreux domaines d'application. Face à la complexité de mesurer un phénomène caché comme la consommation de stupéfiants, la valeur ajoutée de cette approche a ainsi pu être démontrée.

Conceptual Interpretation of LOM and its Mapping to Common Sense Ontologies

Peer-reviewed

Prescription in the proposal for a common european sales law

The rules on prescription in Part VIII, Chapter 18, of the Proposal for a Common European Sales Law (CESL) follow the provisions of the Principles of European Contract Law (PECL) and the Draft Common Frame of Reference (DCFR), which, in general, have deserved favourable comments. Yet, a number of rules contained in those texts have been omitted. It is necessary to ascertain whether the CESL rules only apply to provisions on rights and claims resulting from sales or related services contracts, or whether they are also applicable to any other contractual right or claim and also to rights or claims of non-contractual origin. One of the most problematic issues concerns general prescription periods: firstly, because there are two general periods, a short one and a long one, without any specification about the claims or rights covered by each one of them; secondly, because neither period is suitable in case of non-conformity. There are also some interpretation problems due to missing, ambiguous or defective definitions. The systematic approach demands clarification too.

Outsourcing Challenges in Russia

The study focuses on the key factors in outsourcing from the viewpoint of manufacturing companies operating in Russia. The goal has been to give an overview of the different kinds of challenges companies might face in the case of outsourcing. Of particular interest are the possible risks which might originate from the subcontract relationship, as well as managing these risks. The empirical material for this qualitative interview study was collected from three large-scale manufacturing companies operating in food industry in Russia. Two of the interviewed companies were local Russian actors, and one was an international firm. According to the respondents, a big challenge is to find a suitable supplier in the Russian markets. If there are suppliers available, they may often not be capable of operating as outsourcing partners. The most common problems faced with suppliers are unstable quality and arbitrary pricing. Whether the suppliers are capable to offer activities which satisfy the company’s own and the end customers’ requirements, seems to be the biggest concern in the interviewed companies. This quality risk is managed by the strategy of multiple sourcing. Single sourcing is seen as an impossible option. The interviewed companies have no organised risk management with their external suppliers.

The Pelosi-type versus the modified Misgav-Ladach: a randomized trial of two surgical techniques for cesarean section

Cesarean section (CS) is now the most common major surgical procedure performed on women worldwide. A quarter of deliveries in Spain are performed by cesarean section. With the increasing rates of the operation, there is the need to use evidence-based techniques to optimize outcomes and minimize complications. The goal of this study is to employ a well-designed randomized controlled trial to evaluate the intraoperative blood loss of two surgical techniques for cesarean section, the Pelosi-type and the modified Misgav-Ladach. The trial will take place in Hospital Universitari de Girona Dr. Josep Trueta From 2014 to 2015, 512 pregnant women undergoing delivery by their first lower segment cesarean section in this center will be selected through a consecutive nonprobability sampling. We will collect the main obstetrical characteristics, intraoperative outcomes, short-term outcomes for the baby and postoperative outcomes. We will evaluate the intraoperative blood loss by comparing the changes in hemoglobin levels, pre and postoperatively. Patients will be followed during the postoperative period and in a two-week postoperative appointment. We will analyze the continuous variables, such as the differences in hemoglobin levels, using an unpaired two-sided Student’s t-test, while for the categorical variables Fischer’s exact test will be used

Bayesian Estimation of Noise

In mathematical modeling the estimation of the model parameters is one of the most common problems. The goal is to seek parameters that fit to the measurements as well as possible. There is always error in the measurements which implies uncertainty to the model estimates. In Bayesian statistics all the unknown quantities are presented as probability distributions. If there is knowledge about parameters beforehand, it can be formulated as a prior distribution. The Bays’ rule combines the prior and the measurements to posterior distribution. Mathematical models are typically nonlinear, to produce statistics for them requires efficient sampling algorithms. In this thesis both Metropolis-Hastings (MH), Adaptive Metropolis (AM) algorithms and Gibbs sampling are introduced. In the thesis different ways to present prior distributions are introduced. The main issue is in the measurement error estimation and how to obtain prior knowledge for variance or covariance. Variance and covariance sampling is combined with the algorithms above. The examples of the hyperprior models are applied to estimation of model parameters and error in an outlier case.

PK-YRITYKSET INNOVAATTOREINA : Satunnaisista parannuksista kohti innovaatioiden virtaa. Yhteenveto tutkimusraportista, 3/2009

Tämän tutkimuksen tarkoituksena oli selvittää, minkälaisia innovaatioita eri toimialojen pienissä yrityksissä on kehitetty ja minkälaisia kyvykkyyksiä se on edellyttänyt. Lisäksi tavoitteena oli selvittää, kuinka suotuisana ympäristönä yritykset kokivat oman alueensa ja miten alueiden kehittämistyö on vaikuttanut yritysten kykyyn kilpailla. Teoreettiset oletukset perustuvat aikaisempiin tutkimuksiin innovaatiojohtamisen, yrittäjyyden ja pk-yritysten liiketoiminnan kehittämisen alueilta. Empiirinen aineisto on kerätty sähköpostikyselyllä tuottaen 733 kriteerit täyttävää vastausta. Kyselytutkimusta edelsi neljän alueen tapaustutkimus, jonka aikana luotiin teoreettinen rakennelma pienten yritysten innovaatiokyvykkyyden arvioimiseksi. Tämän tutkimuksen aineisto ei tue yleistä väitettä, jonka mukaan innovaatiotoiminta olisi harvinaisempaa tai vähäisempää kooltaan pienemmissä yrityksissä. Kokoa enemmän näyttäisi vaikuttavan innovaatiotoiminnan luonne ja siihen kytkeytyvä kyvykkyys. Yritysten innovaatio-toiminnan luonteen ja laajuuden perusteella tuloksista nousee neljä erilaista innovaattoriprofiilia: satunnainen parantaja, jatkuva parantaja, radikaali uudistaja ja monipuolinen kehittäjä. Innovaatiokyvykkyyttä tutkittiin seitsemän eri osatekijän suhteen. Eri profiilit omaavien yritysten kyvykkyyden tasot erosivat toisistaan merkittävästi. Tulokset vahvistavat käsityksiä siitä, että yksittäisen kyvykkyystekijän sijaan kyvykkyyskombinaatio vaikuttaa enemmän innovatiotoiminnan monipuolisuuteen. Innovaatiotoiminnan lisääntyessä ja monipuolistuessa, yritysten kyvykkyys-vaatimukset kasvavat kaikkien osatekijöiden suhteen. Yritykset ovat tiedostaneet innovaatio-kyvykkyyden kehittämisen tarpeet. Kyvykkyys on ajuri, jonka kyydissä pienet ja suuret innovaatiot syntyvät. Tämä tutkimus suosittelee, että innovaatiokyvykkyyden kehittäminen nostetaan näkyväm-mäksi tavoitteeksi. Pienissä yrityksissä luontevin tapa vahvistaa kyvykkyyksiä on integroida se yrityksen kehittämistoimintaan johtaen itse itseään ruokkivaksi prosessiksi. Haasteelliset kehittämis-tavoitteet edellyttävät monipuolista kyvykkyyksien vahvistamista ja vahvistuneet kyvykkyydet mahdollistavat entistä haastavampien kehittämistavoitteiden asettamisen. Parhaimmillaan tämä prosessi johtaa pienelle yritykselle soveltuvaan onnistumisen spiraaliin, joka samanaikaisesti kiihdyttää sekä kyvykkyyksien että innovaatioiden kehittämistä - tuotoksena jatkuva ja monipuolinen innovaatioiden virta. Tulokset vahvistavat ensimmäisessa vaiheessa toteutetun tapaustutkimuksen havaintoja siitä, että alueiden kehittämistyöstä hyötyvät yritykset, joiden kyvykkyystekijät ovat entuudestaan korkeaa tasoa. Pitkälle tuotteistetut julkiset palvelut soveltuvat parhaiten suuremmille yrityksille, joissa kehittämistoiminta on projektoitu ja kehittämistyö tehdään erillisten resurssien turvin. Sitä vastoin, valtaosassa pieniä yrityksiä kehittämistyö tapahtuu tavanomaisen liiketoiminnan ohessa ja samoilla resursseilla. Alueet tarjoavat varsin runsaasti luonteeltaan epäjatkuvia palveluja kohdistuen yksittäisten kyvykkyystekijöiden parantamiseen tai prosessin yksittäiseen vaiheeseen, usein innovaatioprosessin alkupäähän radikaalin innovaation kehittämiseksi. Tämän kyselyn tulokset suosittelevat myös toista reittiä: vahvistetaan ensin yritysten innovaatiokyvykkyyttä jatkuvaan pieniä askelia ottavaan innovaatiotoimintaan, josta matka jatkuu radikaalien uudistusten kautta moni-puoliseksi kehittämiseksi.

Expertise and decision making among clinicians in investigations of alleged child sexual abuse

The purpose of the present thesis was to explore different aspects of decision making and expertise in investigations of child sexual abuse (CSA) and subsequently shed some light on the reasons for shortcomings in the investigation processes. Clinicians’ subjective attitudes as well as scientifically based knowledge concerning CSA, CSA investigation and interviewing were explored. Furthermore the clinicians’ own view on their expertise and what enhances this expertise was investigated. Also, the effects of scientific knowledge, experience and attitudes on the decision making in a case of CSA were explored. Finally, the effects of different kinds of feedback as well as experience on the ability to evaluate CSA in the light of children’s behavior and base rates were investigated. Both explorative and experimental methods were used. The purpose of Study I was to investigate whether clinicians investigating child sexual abuse (CSA) rely more on scientific knowledge or on clinical experience when evaluating their own expertise. Another goal was to check what kind of beliefs the clinicians held. The connections between these different factors were investigated. A questionnaire covering items concerning demographic data, experience, knowledge about CSA, selfevaluated expertise and beliefs about CSA was given to social workers, child psychiatrists and psychologists working with children. The results showed that the clinicians relied more on their clinical experience than on scientific knowledge when evaluating their expertise as investigators of CSA. Furthermore, social workers possessed stronger attitudes in favor of children than the other groups, while child psychiatrists had more negative attitudes towards the criminal justice system. Male participants held less strong beliefs than female participants. The findings indicate that the education of CSA investigators should focus more on theoretical knowledge and decision making processes as well as the role of beliefs In Study II school and family counseling psychologists completed a Child Sexual Abuse Attitude and Belief Scale. Four CSA related attitude and belief subscales were identified: 1. The Disclosure subscale reflecting favoring a disclosure at any cost, 2. The Pro-Child subscale reflecting unconditional belief in children's reports, 3. The Intuition subscale reflecting favoring an intuitive approach to CSA investigations, and 4. The Anti Criminal Justice System subscale reflecting negative attitudes towards the legal system. Beliefs that were erroneous according to empirical research were analyzed separately. The results suggest that some psychologists hold extreme attitudes and many erroneous beliefs related to CSA. Some misconceptions are common. Female participants tended to hold stronger attitudes than male participants. The more training in interviewing children the participants have, the more erroneous beliefs and stronger attitudes they hold. Experience did not affect attitudes and beliefs. In Study III mental health professionals’ sensitivity to suggestive interviewing in CSA cases was explored. Furthermore, the effects of attitudes and beliefs related to CSA and experience with CSA investigations on the sensitivity to suggestive influences in the interview were investigated. Also, the effect of base rate estimates of CSA on decisions was examined. A questionnaire covering items concerning demographic data, different aspects of clinical experience, self-evaluated expertise, beliefs and knowledge about CSA and a set of ambiguous material based on real trial documents concerning an alleged CSA case was given to child mental health professionals. The experiment was based on a 2 x 2 x 2 x 2 (leading questions: yes vs no) x (stereotype induction: yes vs no) x (emotional tone: pressure to respond vs no pressure to respond) x (threats and rewards: yes vs no) between-subjects factorial design, in which the suggestiveness of the methods with which the responses of the child were obtained were varied. There was an additional condition in which the material did not contain any interview transcripts. The results showed that clinicians are sensitive only to the presence of leading questions but not to the presence of other suggestive techniques. Furthermore, the clinicians were not sensitive to the possibility that suggestive techniques could have been used when no interview transcripts had been included in the trial material. Experience had an effect on the sensitivity of the clinicians only regarding leading questions. Strong beliefs related to CSA lessened the sensitivity to leading questions. Those showing strong beliefs on the belief scales used in this study were even more prone to prosecute than other participants when other suggestive influences than leading questions were present. Controversy exists regarding effects of experience and feedback on clinical decision making. In Study IV the impact of the number of handled cases and of feedback on the decisions in cases of alleged CSA was investigated. One-hundred vignettes describing cases of suspected CSA were given to students with no experience with investigating CSA. The vignettes were based on statistical data about symptoms and prevalence of CSA. According to the theoretical likelihood of CSA the children described were categorized as abused or not abused. The participants were asked to decide whether abuse had occurred. They were divided into 4 groups: one received feedback on whether their decision was right or wrong, one received information about cognitive processes involved in decision making, one received both, and one did not receive feedback at all. The results showed that participants who received feedback on their performance made more correct positive decisions and participants who got information about decision making processes made more correct negative decisions. Feedback and information combined decreased the number of correct positive decisions but increased the number of correct negative decisions. The number of read cases had in itself a positive effect on correct positive decision.

Recomendações para calibração em química analítica: parte I. Fundamentos e calibração com um componente (calibração univariada)

This paper is a translation from IUPAC nomenclature document by K. Danzer and L. A. Currie (Pure Appl. Chem., 1998, 70(4), 993-1014). Its goal is to establish an uniform and meaningful approach to terminology (in Portuguese), notation, and formulation for calibation in analytical chemistry. In this first part, general fundamentals of calibration are presented, namely for both relationships of qualitative and quantitative variables (relations between variables characterizing certain types analytes of the measured function on the other hand and between variables characterizing the amount or concentration of the chemical species and the intensities of the measured signals, on the other hand). On this basis, the fundamentals of the common single component calibration (Univariate Calibration) which models the relationship y = f(x) between the signal intensities y and the amounts or concentrations x of the analyte under given conditions are represented. Additional papers will be prepared dealing with extensive relationships between several intensities and analyte contents, namely with multivariate calibrations and with optimization and experimental design.

Toimintamalli asuinkiinteistö öljyvahingon hoitamiseksi

Pienkiinteistöjen öljyvahingot ovat viime vuosina lisääntyneet. Tämän työn tarkoituksena on luoda öljyvahingon torjuntaan ja jälkihoitoon osallistuvalle urakoitsijalle toimintamalli asuinkiinteistön öljyvahingon hoitamiseksi. Mallin halutaan erityisesti kuvaavan öljyvahingon hoitoon osallistuvien viranomaisten ja muiden tahojen vastuita ja velvollisuuksia. Työn tavoitteena on myös tunnistaa pienkiinteistöissä tapahtuvat öljyvahinkotyypit sekä niille altistavat riskitekijät. Öljyn päästäminen ympäristöön sekä öljyn käsittely ja varastointi niin, että siitä aiheutuu öljyvahingon vaara, kielletään laissa. Vahinkojen torjumiseksi on annettu määräyksiä muun muassa öljylämmityslaitteistojen turvallisuutta koskien. Asuinkiinteistöjen öljyvahingot liittyvät yleensä öljysäiliön täyttötilanteisiin. Vahinkojen syynä on usein säiliön ja sen varusteiden puutteellisuus tai huono kunto. Asuinrakennusten lämmitykseen käytetään kevyttä polttoöljyä. Maahan joutuessaan polttoöljy imeytyy sora- ja hiekkamaahan nopeasti, jolloin vaarana on öljyn kulkeutuminen pohjaveteen ja vesistöihin. Asuinkiinteistön öljyvahingossa öljyä joutuu usein myös rakenteisiin. Öljyvahingosta tulee ilmoittaa aina hätäkeskukseen. Vastuu öljyvahinkojen torjunnasta kuuluu alueelliselle pelastustoimelle. Torjuntatoimiin osallistuu usein myös urakoitsija. Jos vahinkokohdetta ei torjuntatoimin saada kunnostettua, alueellinen ympäristökeskus voi määrätä puhdistamisesta vastuussa olevan selvittämään pilaantuneen alueen laajuuden ja puhdistamistarpeen sekä toteuttamaan mahdollisen kunnostuksen. Pilaantuneen maaperän kunnostus voidaan toteuttaa massan vaihtona tai paikan päällä maata kaivamatta. Likaantuneiden rakenteiden saneerausta tarvitaan sisäilman hajuhaittojen poistamiseksi. Öljyvahingon kustannukset voivat nousta hyvinkin suuriksi. Ensisijainen vastuu niistä kuuluu vahingonaiheuttajalle.

Knapsack sets for cryptography

The basic goal of this study is to extend old and propose new ways to generate knapsack sets suitable for use in public key cryptography. The knapsack problem and its cryptographic use are reviewed in the introductory chapter. Terminology is based on common cryptographic vocabulary. For example, solving the knapsack problem (which is here a subset sum problem) is termed decipherment. Chapter 1 also reviews the most famous knapsack cryptosystem, the Merkle Hellman system. It is based on a superincreasing knapsack and uses modular multiplication as a trapdoor transformation. The insecurity caused by these two properties exemplifies the two general categories of attacks against knapsack systems. These categories provide the motivation for Chapters 2 and 4. Chapter 2 discusses the density of a knapsack and the dangers of having a low density. Chapter 3 interrupts for a while the more abstract treatment by showing examples of small injective knapsacks and extrapolating conjectures on some characteristics of knapsacks of larger size, especially their density and number. The most common trapdoor technique, modular multiplication, is likely to cause insecurity, but as argued in Chapter 4, it is difficult to find any other simple trapdoor techniques. This discussion also provides a basis for the introduction of various categories of non injectivity in Chapter 5. Besides general ideas of non injectivity of knapsack systems, Chapter 5 introduces and evaluates several ways to construct such systems, most notably the "exceptional blocks" in superincreasing knapsacks and the usage of "too small" a modulus in the modular multiplication as a trapdoor technique. The author believes that non injectivity is the most promising direction for development of knapsack cryptosystema. Chapter 6 modifies two well known knapsack schemes, the Merkle Hellman multiplicative trapdoor knapsack and the Graham Shamir knapsack. The main interest is in aspects other than non injectivity, although that is also exploited. In the end of the chapter, constructions proposed by Desmedt et. al. are presented to serve as a comparison for the developments of the subsequent three chapters. Chapter 7 provides a general framework for the iterative construction of injective knapsacks from smaller knapsacks, together with a simple example, the "three elements" system. In Chapters 8 and 9 the general framework is put into practice in two different ways. Modularly injective small knapsacks are used in Chapter 9 to construct a large knapsack, which is called the congruential knapsack. The addends of a subset sum can be found by decrementing the sum iteratively by using each of the small knapsacks and their moduli in turn. The construction is also generalized to the non injective case, which can lead to especially good results in the density, without complicating the deciphering process too much. Chapter 9 presents three related ways to realize the general framework of Chapter 7. The main idea is to join iteratively small knapsacks, each element of which would satisfy the superincreasing condition. As a whole, none of these systems need become superincreasing, though the development of density is not better than that. The new knapsack systems are injective but they can be deciphered with the same searching method as the non injective knapsacks with the "exceptional blocks" in Chapter 5. The final Chapter 10 first reviews the Chor Rivest knapsack system, which has withstood all cryptanalytic attacks. A couple of modifications to the use of this system are presented in order to further increase the security or make the construction easier. The latter goal is attempted by reducing the size of the Chor Rivest knapsack embedded in the modified system. '

First record of the common bream (Abramis brama) introduced to the Iberian Peninsula

This is the first record of the common bream, Abramis brama (Linnaeus, 1758), introduced into the Iberian Peninsula. Eight individuals of this cyprinid fish species were captured (of a total of 978 fish) in the Boadella Reservoir (Catalonia, Spain) on August 18, 2004. This reservoir is only 14 km away from France, where the bream is native, and contains several exotic freshwater fish that are still not widespread in Spain. The further introduction of species and the illegal translocation of the bream by anglers to other Iberian river basins should be controlled by the Spanish administration

Eliminating Software Failures - A Literature Survey

Software faults are expensive and cause serious damage, particularly if discovered late or not at all. Some software faults tend to be hidden. One goal of the thesis is to figure out the status quo in the field of software fault elimination since there are no recent surveys of the whole area. Basis for a structural framework is proposed for this unstructured field, paying attention to compatibility and how to find studies. Bug elimination means are surveyed, including bug knowhow, defect prevention and prediction, analysis, testing, and fault tolerance. The most common research issues for each area are identified and discussed, along with issues that do not get enough attention. Recommendations are presented for software developers, researchers, and teachers. Only the main lines of research are figured out. The main emphasis is on technical aspects. The survey was done by performing searches in IEEE, ACM, Elsevier, and Inspect databases. In addition, a systematic search was done for a few well-known related journals from recent time intervals. Some other journals, some conference proceedings and a few books, reports, and Internet articles have been investigated, too. The following problems were found and solutions for them discussed. Quality assurance is testing only is a common misunderstanding, and many checks are done and some methods applied only in the late testing phase. Many types of static review are almost forgotten even though they reveal faults that are hard to be detected by other means. Other forgotten areas are knowledge of bugs, knowing continuously repeated bugs, and lightweight means to increase reliability. Compatibility between studies is not always good, which also makes documents harder to understand. Some means, methods, and problems are considered method- or domain-specific when they are not. The field lacks cross-field research.