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Background Information about the impact of cancer treatments on patients' quality of life (QoL) is of paramount importance to patients and treating oncologists. Cancer trials that do not specify QoL as an outcome or fail to report collected QoL data, omit crucial information for decision making. To estimate the magnitude of these problems, we investigated how frequently QoL outcomes were specified in protocols of cancer trials and subsequently reported. Design Retrospective cohort study of RCT protocols approved by six research ethics committees in Switzerland, Germany, and Canada between 2000 and 2003. We compared protocols to corresponding publications, which were identified through literature searches and investigator surveys. Results Of the 173 cancer trials, 90 (52%) specified QoL outcomes in their protocol, 2 (1%) as primary and 88 (51%) as secondary outcome. Of the 173 trials, 35 (20%) reported QoL outcomes in a corresponding publication (4 modified from the protocol), 18 (10%) were published but failed to report QoL outcomes in the primary or a secondary publication, and 37 (21%) were not published at all. Of the 83 (48%) trials that did not specify QoL outcomes in their protocol, none subsequently reported QoL outcomes. Failure to report pre-specified QoL outcomes was not associated with industry sponsorship (versus non-industry), sample size, and multicentre (versus single centre) status but possibly with trial discontinuation. Conclusions About half of cancer trials specified QoL outcomes in their protocols. However, only 20% reported any QoL data in associated publications. Highly relevant information for decision making is often unavailable to patients, oncologists, and health policymakers.

Foreign body (FB) injury from aspiration or ingestion is a common pediatric health problem. Diagnosis relies on clinical judgment plus medical history, physical examination, and radiographic evaluation. A multi-institutional review of 1269 FB events revealed that 85% were correctly diagnosed following a single physician encounter. However, 15% of the children had an elusive diagnosis (>1 week), despite previous evaluation. Delays in diagnosis were seven times more likely to occur in aspirations than in ingestions. Secondary injuries (e.g., pneumonia and atelectasis) occurred in 13% of airway FBs but in only 1.7% of esophageal FBs. Plain radiographs were used in 82% of children, and special studies (e.g., fluoroscopy) in only 7%. We conclude that diagnosis of FB injury in children is frequently achieved at the initial evaluation but that continued surveillance by follow-up visits to health care facilities from parents and other caretakers is important, to reduce pulmonary injuries.

Acartia tonsa Dana represents a genus of temperate-tropical inshore copepods which, by virtue of its high biomass and rapid generation times, may be assumed to be an important planktonic primary consumer in terms of total production world-wide; its grazing response to different food concentrations is little known. Using wide ranges of concentrations of phytoplankton cultures, we have found that A. tonsa has a maximum grazing rate of ≈ 10.0 μg chl a1, decreasing to zero below 1.0 μg chl a1. This was confirmed using the more limited range of naturally-occurring particulate material. Although grazing rate became progressively reduced above 10 μg chl a1, ingestion rates continued to increase over the next order of magnitude of food concentration. It appears that A. tonsa is rarely exposed to food concentrations in its natural environment (as measured by conventional techniques) high enough to stimulate the maximum grazing effort. On the other hand, it is suggested that the continued increase of ingestion rates in the laboratory at much higher concentrations may indicate an adaptive mechanism associated with the encountering of ephemeral micro-patches of such concentrations, which would permit rapid filling of an empty gut in an energy-efficient manner. Fecal pellet production was also measured and shown to be a good indicator of ingestion rate.

The passage of food through the gut of Sagitta hispida Conant is described as a batch process and the formation of membranes which surround the faecal material is demonstrated photographically. The utility of such a peritrophic membrane system is considered in the light of the marine ecosystem as a whole.

Methods are described whereby Sagitta hispida Conant was collected, induced to spawn, and the resulting larvae raised to maturity. Selection of food by size increased with age, although the larvae ingested food larger in size relative to their head width than did mature animals. There are wide variations in the size of individuals in growing populations, but mean growth rates are directly proportional, and maximum sizes inversely proportional, to temperatures between 17 and 31 °C. Populations reached maturity in salinites from 25 to 40% and showed less variability with salinity than with temperature. The minimum and maximum time for a population to reach maturity from the egg was 18 and 50 days, respectively.

In reviewing the ecology of planktonic ctenophores, Walter (1976) pointed out how laboratory estimations of such parameters as growth, feeding and fecundity had been utilized to interpret population dynamics of ctenophores in the natural environment. In organisms with short life-cycles, which inhabit the water column, it is usually impossible to follow the growth and mortality characteristics of cohorts by the use of such techniques as size/frequency histograms. The observer can never be sure he is sampling the same population, over a period of time, and even if this were so, continuous breeding and rapid growth tend to quickly obscure the identification of distinct cohorts. It is also not possible to experimentally manipulate the population. This report describes an experiment in which plankton populations were studied in three containers for six weeks following empoundment of a water column and its natural plankton assemblage.

Publisher Summary This chapter summarizes information on nutritional biology (from observations on living animals mostly in the laboratory) of ctenophores and discusses attempts to utilize laboratory data to interpret environmental fluctuations. Fraser, Kremer, Greve have pointed out that ctenophores should not be considered merely wasteful “dead ends” in the food chain. They may act, sometimes, to balance the ecosystem by restraining an overabundance of copepods from virtually eliminating all phytoplankton from the water column at a time when other more useful predators are failing to do this. The phytoplankton would also receive a positive stimulation to renewed growth by virtue of the high percentage of ingested nitrogen being returned in a dissolved form back to the water column. It is possible that the result might otherwise be the production of dead copepod biomass that accumulated in the sediments and was lost to the water column. Growth rate and fecundity of ctenophores are highlighted. The chapter also discusses seasonal variations in ctenophore populations.