Species Diversity of Benthic Macroinvertebrates in the Des Moines River, Iowa

31 leaves.Problem. Evaluation of the water quality of the Des Moines River. Iowa by sampling and analyzing the benthic macroinvertebrate community. Procedure. Artificial substrates at four stations were used to collect benthic macroinvertebrates. Community structure was analyzed with species divorsity indices. Species diversity (D) and redundancy (R) values were used to calculate standardlzed distance (SD) values. The indices were analyzed statistically. Findings. The average D values ranged from 1.62 to 1.94. Mean standardized distance (SD) values were lowest immediately above the metropolitan Des Moines area and highest immediately downstream from the metropolitan Des Moines area. Conclusion. According to species diversity (D) values, the entire Des Moines River in the study area exhibited mild pollution. Differences in: community structure do exist in the river. Differences in standardized distance (SD) values are attributed to influences that the metropolitan area had on the river. Red Rook Reservoir showed no statistically significant effects on the station immediately downstream. Recommendations. Recommendations for further study are: (1) Follow-up species diversity and productivity studies after Saylorville Reservoir is impounded. (2) Follow-up study with more sample sites between stations 2 and 3 incorporating chemical analysis of water to pinpoint the site of most drastic water quality change

Auswirkungen der Torfmooskultivierung auf die Treibhausgasbilanz von Spender-, Vermehrungs- und kommerziellen Anbauflächen sowie Bewässerungspoldern

Die Entwässerung der Moore für Landwirtschaft, Forstwirtschaft und Torfabbau hat diese Ökosysteme in Hotspots der Treibhausgasemission verwandelt. Klassische Wiedervernässungsprojekte können die natürliche Funktion der Moore als Senken des atmosphärischen Kohlenstoffs wiederherstellen, schließen jedoch eine Nutzung aus. Eine Möglichkeit, ökologische und ökonomische Ziele zu vereinen, ist die Kultivierung von Torfmoosen als qualitativ hochwertiges Substrat für den professionellen Gartenbau. Das hier vorgestellte Projekt begleitet den Versuch einer kommerziellen Torfmooskultivierung auf abgetorften Schwarztorfflächen in Niedersachsen. Dabei wird der Austausch von Kohlendioxid (CO2), Methan (CH4) und Lachgas (N2O) der gesamten moorbasierten Produktionskette von einer naturnahen Spenderfläche über die Vermehrungsfläche (einschließlich eines Bewässerungspolders) bis hin zur Kultivierungsfläche über zwei Jahre in einer hohen zeitlichen Auflösung mit der manuellen Haubenmethode gemessen. Die gewonnenen Daten werden Rückschlüsse über die Klimabilanz der Torfmooskultivierung im Vergleich zu einer naturnahen Referenzfläche und über das Potenzial der Torfmooskultivierung, degradierte Moorstandorte wieder zu Kohlenstoff- bzw. Treibhausgassenken umzuwandeln, erlauben. Im Rahmen dieses Projekts untersuchen wir den Einfluss verschiedener biotischer und abiotischer Einflussfaktoren: Zum einen werden auf der Vermehrungsfläche unterschiedliche Torfmoosarten (Sphagnum palustre L., Sphagnum papillosum Lindb. sowie eine Artenmischung) untersucht, und zum anderen wird der Effekt von Wassermanagement und (potenzieller) Erwärmung evaluiert. Dazu kommen auf den Kultivierungsflächen unterschiedliche Bewässerungstechniken zum Einsatz, während in ausgewählten Varianten zusätzlich „Open Top Chambers“ installiert wurden, um den Treibhausgasaustausch unter möglichen zukünftigen Klimawandelbedingungen abschätzen zu können. Bei der Tagung werden erste Messergebnisse präsentiert

Sphagnum farming from species selection to the production of growing media : a review

Sphagnum farming - the production of Sphagnum biomass on rewetted bogs - helps towards achieving global climate goals by halting greenhouse gas emissions from drained peat and by replacing peat with a renewable biomass alternative. Large-scale implementation of Sphagnum farming requires a wide range of know-how, from initial species selection up to the final production and use of Sphagnum biomass based growing media in horticulture. This article provides an overview of relevant knowledge accumulated over the last 15 years and identifies open questions.Peer reviewe

How doctors generate diagnostic hypotheses: a study of radiological diagnosis with functional magnetic resonance imaging.

In medical practice, diagnostic hypotheses are often made by physicians in the first moments of contact with patients; sometimes even before they report their symptoms. We propose that generation of diagnostic hypotheses in this context is the result of cognitive processes subserved by brain mechanisms that are similar to those involved in naming objects or concepts in everyday life

[Fever and dysphagia of a young woman]

We report the case of a 39-year old patient with septicemia treated for pharyngitis with antibiotics since a few days. She wasn't able to swallow her antibiotics anymore because of dysphagia. Radiologic examination revealed pulmonary infiltrates and Vena iugularis interna-thrombosis. These findings and anamnesis led to the diagnosis of Lemierre syndrome inspite of lacking detection of bacteria. After changing the antibiotic therapy and start of anticoagulation further course of illness was favorable. The long duration of hospitalization was indepted to high morbidity typically seen in Lemierre syndrome

[Spontaneous hematomas and isolated prolongation of aPTT]

We report a case of a 64 year old woman with spontaneous hematomas. A prior history of bleeding disorder was not known up to now. The result of investigation of coagulation was an isolated prolonged aPTT that was caused by an inhibitor of factor VIII without underlying disease (idiopathic acquired hemophilia A). Therapy with steroids and cyclophosphamid resulted in partial remission

Radiologic manifestations of bronchoscopic lung volume reduction in severe chronic obstructive pulmonary disease

OBJECTIVE. Bronchoscopic lung volume reduction promises to become an effective treatment option in severe chronic obstructive pulmonary disease. Several techniques are currently being investigated, including implantation of devices into the lung and instillation of hot water vapor or polymer. This article reviews the spectrum of radiologic manifestations on chest radiography and CT that occur after the intervention. CONCLUSION. Familiarity with the intended effects and adverse events will aid the radiologist in supporting bronchoscopic lung volume reduction

PowerMANNA. A parallel architecture based on the PowerPC MPC620

The paper presents PowerMANNA - a distributed-memory parallel computer system based on the 64- bit PowerPC processor MPC620. The PowerMANNA node architecture supports all the sophisticated features of the MPC620 and incorporates important architectural concepts that allow us to exploit the performance of modern superscalar microprocessors in the context of massively parallel supercomputing. The two-way processor nodes of PowerMANNA are embedded in a powerful communication system supporting low-latency communication and maximum connectivity. Processing and communication performance of an eight-node prototype are shown and compared with shared-memory machines and clusters. In the course of the presentation, experience obtained with the PowerPC MPC620 processor is discussed