Effect of zooplankton-mediated trophic cascades on marine microbial food web components (bacteria, nanoflagellates, ciliates)

To examine the grazing effects of copepod-dominated mesozooplankton on heterotrophic microbial communities, four mesocosm experiments using gradients of zooplankton abundance were carried out at a coastal marine site. The responses of different protist groups (nanoflagellates, ciliates) and bacterioplankton in terms of abundance and additionally, for bacteria, diversity, production, and exoenzymatic activity, were monitored during 1 week of incubation. Independent of the initial experimental abiotic conditions and the dominating copepod species, zooplankton caused order-of-magnitude changes in microbial functional groups in a clear community-wide four-link trophic cascade. The strongest predatory effects were observed for protist concentrations, thus generating inverse relationships between mesozooplankton and ciliates and between ciliates and nanoplankton. Copepod grazing effects propagated even further, not only reducing the abundance, production, and hydrolytic activity of bacterioplankton but also increasing bacterial diversity. The overall strength of this trophic cascade was dampened with respect to bacterial numbers, but more pronounced with respect to bacterial diversity and activity. High predation pressure by heterotrophic nanoflagellates, realized at the highest copepod abundance, was probably the underlying mechanism for these structural changes in the bacterial assemblages. Our results thus suggest a mechanism by which changes in higher trophic levels of marine plankton indirectly affect prokaryotic assemblages and microbially mediated ecosystem functions

A characterization of Descartes systems in Haar subspaces

AbstractA characterization of existence of Descartes systems in Haar subspaces is given. Moreover, it is shown that the functions in such systems can be represented as products of piecewise strictly monotone functions

Die Bedeutung der funktionellen Anatomie in China für die Motorik

Zusammenfassung Zusammenfassend wurde versucht, in dieser Arbeit zu zeigen, wie die Selbstheilungskräfte aus der traditionellen chinesischen Medizin, durch die Methoden der westlichen Medizin bestätigt werden können. Die beschriebene Vergleichsstudie ist ein exemplarischer Anfang für weitere Forschung. Wenn es gelingt, die beiden medizinischen Systeme zu einer Ergänzung und gegenseitigen Verbessrung zu bringen, dann wird der Nutzen, sowohl für die gesunde Lebensführung des Einzelnen als auch der Gesellschaft groß sein

CHANGES IN FOOT PRESSURE DISTRIBUTION DURING A COMBINED RUNNING AND CYCLING TEST

Introduction: Very often the great training demands in running lead to an overload of the musculo-skeletal system. Alternative training methods like cycling would be very useful to reduce this overload. In this connection the question arises of how these triathlon-specific combined exercises affect running economy and foot pressure distribution (FPD). Methods: 24 national and international elite triathletes (7 female, V02max 64,3 ml kg-1 min-1, 17 male, V02max 71,2 ml kg-1 min-1) performed a combined runningcycling test in the laboratory. The combined test design consists of three running step tests with two different speed levels (R1, R3, R4). Between R1 and R3 a 20 min endurance exercise test in running, and between R3 and R4 a 30 min endurance exercise test in cycling were each performed with an intensity of 80% V02max. Foot pressure distribution (Novel, Pedar-System), surface electromyography (Biovision), lactate and heart rate were measured in running and cycling. For determination of the pedar masks, the soles of the feet were divided into 9 anatomical masks (Bontranger et al., 1997). Results: The results showed that there were no significant changes in contact area, maximum vertical forces, vertical displacement, contact time between R1 and R3. In contrast to that, after the cycling exercise significant increases were shown between R1 and R4 in maximum vertical forces (v1: +15%, v2: +12 %) and vertical displacement (v1: +9%). Primarily, the changes result from the middle part of the metatarsus. Conclusion: Athletes should be careful when practicing running immediately after cycling in order to reduce vertical stresses. References: Bontranger, E.L., Boyd, L.A. et al. (1997). Determination of Novel Pedar Masks using Harris Mat Imprints. Gait & Posture 4, 167-168

Prospective Multicenter Randomized Phase III Study of Weekly versus Standard Docetaxel (D2) for First-Line Treatment of Metastatic Breast Cancer

Purpose: Previous phase II studies have indicated a greatly reduced hematotoxicity of docetaxel-based regimens administered on weekly schedules. The present trial was initiated to randomly compare the toxicity and efficacy of weekly docetaxel versus its standard 3-weekly application. Methods: Patients previously untreated with chemotherapy for metastatic disease were recruited. Patients aged >60 years or with a Karnofsky Perfomance Status (KPS) of 60-80% were eligible for the D2 study. Patients were randomized to receive docetaxel either on a 3-weekly {[}75 mg/m(2) every 3 weeks (q3w)] or on a weekly (30 mg/m(2) on days 1, 8, and 15; q4w) schedule. Treatment was continued until a maximum of 8 cycles, unacceptable toxicity, or disease progression. All patients received standard corticosteroid prophylaxis. Results: Since statistical significance for the primary endpoint (toxicity) was achieved in the interim analysis, the study was closed according to the study protocol (102 of 162 patients). Compared to the standard arm, leukopenia >= grade 3 was a rare event in the weekly arm of the D2 study (per-patient analysis: 4.2% q1w vs. 51.9% q3w; p < 0.0001). No difference was observed between the 2 schedules regarding the occurrence of anemia or thrombocytopenia. With regard to non-hematological toxicity, there was a higher incidence of skin/nail and hepatological toxicity with the weekly schedule, whereas neurotoxicity was observed more often in the standard arm. The rate of omitted doses was significantly increased in the weekly arm (8.6% q1w vs. 0% q3w). The overall response rate was 22.9% in the weekly arm compared to 42.6% in the standard arm (p = 0.039). Time to progression was 5.4 (q1w) versus 6.3 (q3w) months (p = 0.91), and overall survival was 22.7 (q1w) versus 15.8 (q3w) months (p = 0.24). Conclusion: The present data support the feasibility of both weekly and 3-weekly application of docetaxel. As expected, severe leukopenia seems avoidable in weekly scheduled single-agent docetaxel and may serve as an important treatment option, particularly in elderly patients and patients with a reduced performance status. Copyright (C) 2011 S. Karger AG, Base

Prospective Multicenter Randomized Phase III Study of Weekly versus Standard Docetaxel plus Doxorubicin (D4) for First-Line Treatment of Metastatic Breast Cancer

Purpose: Previous phase II studies have indicated a greatly reduced hematotoxicity of docetaxel-based regimens administered on weekly schedules. The present trial was initiated to compare the toxicity and efficacy of weekly docetaxel versus its standard 3-weekly application in combination with doxorubicin. Methods: Patients previously untreated with chemotherapy for metastatic disease were recruited. Inclusion criteria were age = grade 3 was observed in the standard arm of the D4 study compared to the weekly schedule (per-patient analysis: 61.9% q3w vs. 65.1% q1w; p > 0.05). Grade 3 and grade 4 fever, diarrhea, and infections occurred more frequently in the standard arm, whereas neurotoxicity and skin/nail disorders were observed more frequently in the weekly arm. Except for fever, none of these differences reached a level of significance. Dose delays, dose reductions, and the rate of omitted doses were increased in the weekly arm. The overall response rate was 44.2% in the weekly arm compared to 52.4% in the standard arm (p = 0.52). Time to progression was 6.2 (q1w) versus 10.3 (q3w) months (p = 0.36), and overall survival was 20.5 (q1w) versus 28.7 (q3w) months (p = 0.98). Conclusion: The present data support the feasibility of both weekly and 3-weekly application of docetaxel in combination with doxorubicin. Nevertheless, given that leukopenia was similar in both arms and the efficacy parameters were at least numerically inferior with the weekly schedule, standard 3-weekly application seems to be preferable for patients requiring combination chemotherapy. Copyright (C) 2011 S. Karger AG, Base