Comparison of the cytomorphological classification with the cytochemical differentiation of acute lymphatic leukemia in children]

In 100 children with acute lymphatic leukaemia the cytomorphological subclassification of the pathological cell type was made according to Mathé and the French-American-British Co-operative group (FAB). In addition, all cases of leukaemia were differentiated according to their cytochemical type. Lymphoblasts from 10 cases of leukaemia could be subclassified immunologically. From 71 children will ALL the survival rates of those cases of leukaemia subclassified cytomorphologically and the cytochemical reactions were compiled and partially compared. Microlymphoblastic leukaemia could be found to be the most frequent type of ALL at children's age. Prolymphocytic leukaemias were characterized by a favourable survival rate and the highest percentage of ALL with the PAS type. Macrolymphoblastic and microlymphoblastic cases of leukaemia revealed no essential differences of survival rate, but significant differences of cytochemical reactions.     

Darting and marking techniques for an arboreal forest monkey,Cercopithecus ascanius

Techniques are described for capturing and marking redtail monkeys (Cercopithecus ascanius). An air-powered darting rifle and syringe darts loaded with a Ketamine-Rompun mixture were used for capture. Ketamine was used for maintaining anesthesia. Monkeys were darted 48 times and captured 27 times. In 24 of the 27 captures, the monkeys were released unharmed. Adult males were marked with radiotransmitters attached to collars of nylon webbing. Females received nylon webbing collars with colorcoded plastic washers for identification.     

Environmental stress alters native-nonnative relationships at the community scale

The invasion of natural habitats by nonnative species is affected by both native biodiversity and environmental conditions; however few tests of facilitation between native community members and nonnative species have been conducted along disturbance and stress gradients. There is strong evidence for an increase in facilitation between native plant species with increasing levels of natural environmental stress, however it is unknown whether these same positive interactions occur between nonnative invaders and native communities. I investigated the effects of natural stress on community interactions between native heathland species and nonnative species with two field studies conducted at the landscape and community scale. At the landscape scale of investigation, nonnative species richness was positively related to native species richness. At the community level, nonnative invaders experienced facilitation with natives in the most stressful zones, whereas they experienced competition with native plants in the less stressful zones of the heathlands. Due to the observational nature of the landscape scale data, it is unclear whether nonnative diversity levels are responding positively to extrinsic factors or to native biodiversity. The experimental component of this research suggests that native community members may ameliorate stressful environmental conditions and facilitate invasion into high stress areas. I present a conceptual model which is a modification of the Shea and Chesson diversity-invasibility model and includes both facilitation as well as competition between the native community and nonnative invaders at the community level, summing to an overall positive relationship at the landscape scale.     

Community composition has greater impact on the functioning of marine phytoplankton communities than ocean acidification

Ecosystem functioning is simultaneously affected by changes in community composition and environmental change such as increasing atmospheric carbon dioxide (CO₂) and subsequent ocean acidification. However, it largely remains uncertain how the effects of these factors compare to each other. Addressing this question, we experimentally tested the hypothesis that initial community composition and elevated CO₂ are equally important to the regulation of phytoplankton biomass. We full‐factorially exposed three compositionally different marine phytoplankton communities to two different CO₂ levels and examined the effects and relative importance (ω²) of the two factors and their interaction on phytoplankton biomass at bloom peak. The results showed that initial community composition had a significantly greater impact than elevated CO₂ on phytoplankton biomass, which varied largely among communities. We suggest that the different initial ratios between cyanobacteria, diatoms, and dinoflagellates might be the key for the varying competitive and thus functional outcome among communities. Furthermore, the results showed that depending on initial community composition elevated CO₂ selected for larger sized diatoms, which led to increased total phytoplankton biomass. This study highlights the relevance of initial community composition, which strongly drives the functional outcome, when assessing impacts of climate change on ecosystem functioning. In particular, the increase in phytoplankton biomass driven by the gain of larger sized diatoms in response to elevated CO₂ potentially has strong implications for nutrient cycling and carbon export in future oceans.     

Frequency of anemia in Rostock students]

For the purpose of determining the frequency of anaemia a check-up was made in 735 students (498 females, 237 males) at an age of at least 19 years at the beginning of their university studies. 9.4% of them had subnormal haemoglobin values. 91.3% of them were female students. A comparison between the test persons with a decrease of haemoglobin values and those without it on the one hand and data gathered from the students' health certificate on the other hand, revealed no ensured aetiologic connection. Analyzing the state of health of that group with lowered Hb-values showed that more than half of them suffered from diseases (mostly infections) at the time, when the blood examination was made. A check-up made one year later resulted in a high percentage of normalized values. Comparisons taken from medical literature clearly indicate that the frequency of anaemia of this student population examined here is relatively low in total. From an organizational point of view, complete check-up examinations shoudl be carried out or induced for female students by the outpatient departments working at the institutions of higher learning because they provide better possibilities of covering them.