393 research outputs found
An investigation into accelerated leaching for the purpose of ARD mitigation
World-wide, acid rock drainage (ARD) is one of the biggest environmental challenges facing environments with current or previously active mining activities. Formed from the exposure of sulphide mineral to both water and air, and catalyzed by naturally occurring iron- and sulphur-oxidizing micro-organisms, ARD pollution is predominantly associated with the mining of sulphidic ores and coal. Of particular concern are the large volumes of mining wastes from which the generation of ARD and the associated pollution effects often persist over tens to hundreds of years after mining operations have ceased. Current ARD management strategies focus on the prevention of ARD through mineral waste deposition or remediation options once ARD has formed. These strategies, however, do not remove the risk of ARD generation in the future. The aim of this study was to investigate the removal of the potential for ARD generation from a low-grade copper waste rock through the accelerated removal of the sulphur components via reaction. The three waste rock samples used in this investigation had total sulphur grades of between 2.20 and 3.20 % with the majority of the sulphide present as pyrite, chalcopyrite and galena. Significant quantities of non-sulphide associated iron minerals, predominantly magnetite, were also present in the three samples. The waste rock samples were sourced from mining operations in Chile and South Africa and had a D80 of approximately 0.8 cm. All three waste rock samples were potentially ARD generating
Retrospect, insights and foresights: Biological control of Anobium puntcatum with Spathius exarator: Presentation
Biological control using beneficial organisms is getting more and more important in Integrated Pest Management. An effective strategy in the fight against the most common timber pest species, the furniture beetle Anobium punctatum, is based on the parasitoid wasp species Spathius exarator. This braconid wasp parasitizes its host species by piercing its ovipositor directly through the wood surface followed by oviposition onto the beetle larva. After feeding on the larva and pupation, the adult wasp emerges through a tiny 0.5 mm wide wood hole, which can be clearly distinguished from the 2 mm wide hole of A. punctatum. This enables us to observe easily the treatment success as each new S. exarator exit hole is equivalent to one killed beetle larva. Between 2012 and 2017, the braconid wasps were introduced into about 80 A. punctatum infested buildings. At least twelve treatments over a period of up to three years were performed. On exactly defined areas, the newly emerged exit holes of A. punctatum and S. exarator were counted and the parasitisation rate was calculated. Here we present pooled data of 29 A. punctatum infested churches, successfully treated and monitored over a period of one to five years. Furthermore, as a representative sample, we show the results of one church over a period of six years. We demonstrate the biological control of the common furniture beetle with this braconid wasp as an efficient, sustainable alternative to conventional residual methods. However, after a period of up to three years intensive treatment, a continuous monitoring-program with necessary additional single treatments should follow.Biological control using beneficial organisms is getting more and more important in Integrated Pest Management. An effective strategy in the fight against the most common timber pest species, the furniture beetle Anobium punctatum, is based on the parasitoid wasp species Spathius exarator. This braconid wasp parasitizes its host species by piercing its ovipositor directly through the wood surface followed by oviposition onto the beetle larva. After feeding on the larva and pupation, the adult wasp emerges through a tiny 0.5 mm wide wood hole, which can be clearly distinguished from the 2 mm wide hole of A. punctatum. This enables us to observe easily the treatment success as each new S. exarator exit hole is equivalent to one killed beetle larva. Between 2012 and 2017, the braconid wasps were introduced into about 80 A. punctatum infested buildings. At least twelve treatments over a period of up to three years were performed. On exactly defined areas, the newly emerged exit holes of A. punctatum and S. exarator were counted and the parasitisation rate was calculated. Here we present pooled data of 29 A. punctatum infested churches, successfully treated and monitored over a period of one to five years. Furthermore, as a representative sample, we show the results of one church over a period of six years. We demonstrate the biological control of the common furniture beetle with this braconid wasp as an efficient, sustainable alternative to conventional residual methods. However, after a period of up to three years intensive treatment, a continuous monitoring-program with necessary additional single treatments should follow
Political rights, taxation, and firm valuation : evidence from Saxony around 1900
The extension of the franchise to social groups with less property and income is associated with greater income redistribution from the rich to the poor and extension in the provision of public goods, which leads to the growth of government expenditure. All of these expected changes are costly and therefore a higher taxation of citizens and industrial firms can be expected, which might have negative effects on investors behavior.
The present paper studies the effects of changes in the suffrage in the Kingdom of Saxony at the end of the 19th Century on stock market prices of Saxon firms listed on the Berlin stock exchange: Here the electoral law was changed twice: In 1896 a very restrictive franchise was introduced, which was abolished in 1909 and replaced by a more democratic electoral law. By applying standard event study methodology, we can provide evidence that the restriction of the electoral law had positive effects on Saxon firms on the stock market, where by the extension in 1909 had negative effects on the stock market
Democratic prospects in Imperial Russia : the revolution of 1905 and the political stock market
This paper assesses the attitude of investors towards Democratic change by performing an event study using Russian government bonds. The Revolution of 1905 offers an ideal occasion as, alongside the related revolutionary events, it was accompanied by two opposing constitutional changes within a short period of time. This study contributes to the debate as to whether Imperial Russia could possibly have followed other Western European states, i.e. gradually adopting a democratic rule, or whether a revolution was inevitable as the writing of Soviet history suggests. Furthermore, the Russo-Japanese War is taken into consideration. The results are basically in line with the literature on the impact of wars on capital markets. Prices of two types of bonds on both the Saint Petersburg and the Berlin stock exchange are employed. As it turns out, investors in the East and West were largely consistent in their reactions
Political economy and stock markets in long-term perspective
The dissertation finds widespread connections between firms and the parliament in pre- and interwar Germany. It also gives a comprehensive overview of respective firm and party characteristics. Unlike previous work, the sample includes three different periods, representing three distinct political systems. The regime type mattered a lot, since connections did not add value to a firm homogeneously during monarchy, democracy and dictatorship. They proved effective in general only under National Socialist rule, consistent with previous literature. In the Weimar Republic, only political and economic heavyweights paid off, while in Imperial Germany firms could not benefit from a link to the parliament. Various robustness checks are applied, including propensity score matching, coarsened exact matching and panel data analysis. In addition, the probability of a firm to remain on the market is considered: connected firms were more likely to survive than their non-connected counterparts, especially in times of crisis.
Furthermore, the dissertation assesses the price reaction of Russian government bonds using event study methodology. The Revolution of 1905 offers an ideal occasion, as it was accompanied by two opposing constitutional changes within a short period of time. The result contributes to the debate as to whether Imperial Russia could possibly have followed other Western European states, i.e. gradually adopting a democratic rule, or whether a revolution was inevitable as the writing of Soviet history suggests. As it turns out, investors did not perceive the ongoing as a threat. Rather they considered long-run democratic change to be a realistic. Furthermore, the Russo-Japanese War is taken into consideration, resembling the existing literature. The assessment is based on two types of bonds, listed at both the Saint Petersburg and the Berlin Stock Exchange. Investors in the East and West were largely consistent in their reactions.Die Dissertation findet vielfache Verbindungen zwischen Unternehmen und dem Parlament im Deutschland der Vor- und Zwischenkriegszeit. Weiterhin gibt sie einen umfassenden Überblick über die jeweilige Firmen- und Parteimerkmale. Im Gegensatz zu früheren Arbeiten umfasst sie drei unterschiedliche Zeiträume, die drei verschiedene politische Systeme wiederspiegeln. Der Regimetyp ist von Bedeutung, da Verbindungen nicht gleichartig zum Firmenwert beitragen unter der Monarchie, Demokratie und Diktatur. Sie erweisen sich als wirksam in der Regel nur unter der NS-Herrschaft, entsprechend der bisherigen Literatur. In der Weimarer Republik haben sich nur politische und wirtschaftliche Schwergewichte ausgezahlt, während im kaiserlichen Deutschland Unternehmen nicht von einer Verbindung zum Parlament profitieren konnten. Die Robustheit der Resultate wird überprüft anhand propensity score matching, coarsened exact matching und Paneldatenanalyse. Darüber hinaus wird die Wahrscheinlichkeit eines Unternehmens am Markt zu bleiben betrachtet: Diese ist höher für verbundene Firmen, vor allem in Zeiten der Krise.
Darüber hinaus bewertet die Arbeit die Preisreaktion russischer Staatsanleihen mithilfe einer Ereignis Studie. Die Revolution von 1905 bietet eine ideale Gelegenheit, da sie von zwei Verfassungsänderungen innerhalb kurzer Zeit begleitet wurde. Das Ergebnis trägt bei zur Debatte darüber, ob das zaristischen Russland möglicherweise den Weg anderer westeuropäischer Staaten hätte gehen können oder ob eine Revolution unvermeidlich war - wie die sowjetische Geschichtsschreibung behauptet. Wie sich herausstellt, werden die Ereignisse von Investoren nicht als besonders bedrohlich eingestuft. Vielmehr erscheint ein demokratischer Wandel langfristig realistisch. Darüber wird der russisch-japanischen Krieg betrachtet. Die Einordnung erfolgt basierend auf zwei verschiedenen Staatsanleihen, die sowohl an der Sankt Petersburger und an der Berliner Börse gehandelt werden. Die Reaktionen der Investoren in Ost und West waren weitestgehend konsistent
Violent Behavior During Psychiatric Inpatient Treatment in a German Prison Hospital
Violent behavior in correctional facilities is common and differs substantially in type, target, implication, and trigger. Research on frequency and characteristics of violent behavior in correctional facilities and psychiatric hospitals is limited. Results from recent research suggest that comorbidity of severe mental disorder, personality disorder, and diagnosis of substance abuse is related to a higher risk of violent behavior. In the Berlin prison hospital, a database was created to collect data from all violent incidences (n=210) between 1997 and 2006 and between 2010 and 2016. In a retrospective, case-control study, we analyzed specific socioeconomic data and psychiatric diagnosis and compared the group of prisoners with violent behavior with randomly selected prisoners of the same department without violent behavior (n = 210). Diagnosis of schizophrenia, non-German nationality, no use of an interpreter, no children, and no previous sentence remained significantly associated with the dependent variable violent behavior. There were no significant differences regarding age and legal statuses. Practical implications for clinical work are discussed
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