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1. The habitat heterogeneity (HHH) and individual adjustment (IAH) hypotheses are commonly proposed to explain a decrease in reproduction rate with increasing population density. Higher numbers of low-quality territories with low reproductive success as density increases lead to a decrease in reproduction under the HHH, while more competition at high density decreases reproduction across all territories under the IAH. 2. We analyse the influence of density and habitat heterogeneity on reproductive success in eight populations of long-lived territorial birds of prey belonging to four species. Sufficient reliability in distinguishing between population-wide, site-specific and individual quality effects on reproduction was granted through the minimal duration of 20 years of all data sets and the ability to control for individual quality in five of them. 3. Density increased in five populations but reproduction did not decrease in these. Territory occupancy as a surrogate of territory quality correlated positively with reproductive success but only significantly so in large data sets with more than 100 territories. 4. Reproductive success was always best explained by measures of territory quality in multivariate models. Direct or delayed (t-1) population density entered very few of the best models. Mixed models controlling for individual quality showed an increasing reproductive performance in older individuals and in those laying earlier, but measures of territory quality were also always retained in the best models. 5. We find strong support for the habitat heterogeneity hypothesis but weak support for the individual adjustment hypothesis. Both individual and site characteristics are crucial for reproductive performance in long-lived birds. Proportional occupancy of territories enables recognition of high-quality territories as preferential conservation targets., (© 2011 The Authors. Journal of Animal Ecology © 2011 British Ecological Society.)

The aim of the current study was to describe the incidence of respiratory symptoms and allergic sensitisation and the sequence of events leading to respiratory symptoms among Danish baker apprentices (BA). A total of 114 BA were surveyed over a 20-month period. Questionnaires were completed along with spirometric analysis and skin-prick tests to common and work-related allergens. Bronchial hyperresponsiveness (BHR) was determined at baseline and at the end of the follow-up period. The incidences of work-related rhinitis and asthma-like symptoms were 22.1 and 10.0 cases.100 person-yrs(-1), respectively. At 20 months the cumulative incidence proportion was 40.2 and 20.5% for rhinitis and asthma-like symptoms, respectively. The cumulative incidence of occupational sensitisation was 6.1%. An increased risk of asthma-like symptoms was found in both atopic subjects and in females. In the BA with new onset respiratory symptoms, an increase in BHR from baseline was observed. Forced expiratory volume in one second and forced vital capacity did not change during the follow-up period. No relationship was observed between new sensitisation and new symptoms. In conclusion rhinitis- and asthma-like symptoms were found to develop commonly in Danish baker apprentices. The mechanism by which symptoms arose was perceived to reflect the development of an inflammation rather than the production of a specific immunoglobulin E pathway, as sensitisation to occupational allergens was rarely observed. Hence, respiratory symptoms and allergy may develop through separate pathways.

A total of 379 patients admitted to the Intensive Care Unit (ICU) for mechanical ventilation were prospectively investigated for lesions of the nose, nasal cavity, ears and larynx during and after nasotracheal intubation. One to two years later, the surviving patients were questioned to investigate late persisting sequelae. During intubation and up to five days following extubation, inflammatory changes and ulceration of the nostrils or nasal septum were found in respectively 76 (20%) and 110 (29%) patients. There were bleedings from the nasal cavity in 67 (19%) and fractures of the conchae in 40 patients (11%). Hoarseness was noted in 135 patients (42%). Inflammatory changes and ulcerations of the nostril and nasal septum were correlated to the duration of intubation. Among the 281 patients included in the follow-up study, 100 (35%) had symptoms from the nose and nasal cavity. Sixty-five (24%) had symptoms related to the ears, 56 (20%) to the maxillary sinus, 81 (29%) to the voice and 90 (32%) to the throat. Increasing duration of intubation was found to be correlated to persisting symptoms from the larynx. Former ulcerations of the nose were associated with a tendency toward nasal bleeding. To avoid as many complications as possible from the nose and nasal cavity, we recommend orotracheal intubation. As late sequelae from the larynx increase with the duration of intubation, perhaps tracheostomy should be performed earlier than is general practice today, but that has to be proven in forthcoming studies.

Long-term respirator treatment in the patients' own home is instituted increasingly frequently in patients with neuromuscular diseases. Positive pressure ventilation via a permanent tracheostomy is employed. Treatment is frequently commenced electively during hospitalization in particularly interested departments. Discharge to the patients' home is undertaken after thorough instruction of the patient himself, the family and the persons who help the patient with his other daily needs. Possible guidelines for establishing this form of treatment are outlined on the basis of literature from abroad.