Degenerate dentition of the dugong (Dugong dugon), or why a grazer does not need teeth: morphology, occlusion and wear of mouthparts

The morphology and functional occlusion of the cheekteeth of 57 dugongs Dugong dugon of both sexes were examined using reflected light and scanning electron microscopy, radiography, hardness testing and skull manipulation. The functional morphology of the horny oral pads was also described. Mouthparts and body size allometry was examined for ontogenetic and gender-related trends. We found that the worn erupted cheekteeth of the dugong are simple flat pegs composed of soft degenerative dentine. During occlusion, the mandible moves in a mainly antero-lingual direction, with the possibility of mandibular retraction in some individuals. Anterior parts of the cheektooth row may become non-functional as a dugong ages. As a function of body size, dugong cheekteeth are extremely small compared with those of other mammalian herbivores, and with other hindgut fermenters in particular. The morphology, small size and occlusal variability of the cheekteeth suggest that there has not been strong selective pressure acting to maintain an effective dentition. In contrast, great development of the horny pads and associated skull parameters and their lower size variability suggest that the horny pads may have assumed the major role in food comminution.

Mechanical disruption of seagrass in the digestive tract of the dugong

The cheek teeth in dugongs are considered to be largely non-functional whereas the oral horny pads are important both in mechanical disruption of the diet and in conveying seagrass through the mouth. Particle size distributions of digesta from 41 dead stranded dugongs were examined to investigate the relationship between degree of food breakdown, gut region and functional surface area of the mouthparts. The in vitro ease of fracture of major dietary seagrass species were compared. The rate of food breakdown through the gut appears to be more closely linked to fibre level of the diet than to size or age of the dugong and its mouthparts. Low fibre seagrass, for example Halophila ovalis, breaks down at a faster rate than high fibre seagrass, for example Zostera capricorni both in dugong guts and in vitro. Several structural characteristics of seagrass, including level and arrangement of fibre, and water content, make it particularly amenable to mechanical breakdown. The soft mouthparts of the dugong are highly modified so that the entire oral cavity functions to crush low fibre seagrasses. Thus, the dugong has developed an efficient method of food ingestion and mastication that is suited to processing large quantities of soft seagrass during short dive times. The potential cost to the dugong in having lost its hard dental surfaces is that it has become restricted to a low fibre diet.

Evaluación de la calidad de un servicio de voluntariado en oncología: un Análisis Importancia-Valoración (IPA)

Objective: Using an Importance-Performance Analysis (IPA), this paper examined a Radiotherapy and Oncological Patient and Non-patient perceived importance and performance of ten Humanization Volunteer Program selection factors in the General Hospital in Spain.Methods: The authors identified a list of seven items from the Health-marketing literature reviews, and each item was rated using a 5-point Likert scale. Responses were obtained of 148 usable interviews.Results: The importance-performance patient grid was corrected with literature recommendations and, in the patient sample, shows three items fall in the “Keep up the good work” quadrant, four items fall into the “Low priority” quadrant, zero items fall into the “Possible overkill” quadrant, and no items fall in the “Concentrate here” quadrant. Non-patient (n=80) factors means shows statistical differences with patient (n=68) means in catering (t=-2.38; df.=146; p<0.05), and information (t=2.16; df146; p<0,05).Conclusions: The results are useful in identifying areas for strategic focus to help Health Services managers develop humanization programs with volunteer workers and different program users. Implication to volunteer programs managers and researchers were discussed.

Does positive mental health in adolescence longitudinally predict healthy transitions in young adulthood?

The present study examined the longer-term implications of adolescent positive mental health for successful young adult transitions. Positive mental health in adolescence was defined by indicators roughly corresponding to Seligman’s positive psychology PERMA framework (positive emotional experiences, engagement, relationships, purpose, and accomplishment), with the addition of health. Data were drawn from one of Australia’s longest running studies of social and emotional development (Australian Temperament Project, est. 1983, N = 2443), which has followed a large representative community sample from infancy to 27–28 years of age. In the analyzed sample of n = 999, positive mental health at 15–16 years was associated with indicators of career progression (educational attainment and perceived competence) and taking on citizenship responsibilities (volunteering and civic activities) over a decade later at 27–28 years. Mental health problems in adolescence were more relevant to establishing romantic partnerships in young adulthood: adolescent antisocial behaviors predicted higher likelihood of being in a relationship, while depressive symptoms predicted lower quality partnerships. The results suggest that successful transitions into young adult roles and responsibilities may be facilitated by targeted mental health promotion interventions designed to both foster positive mental health and address mental health difficulties in adolescence.

Negative reactivity and parental warmth in early adolescence, and depressive symptoms in emerging adulthood

ObjectiveCross-sectional research suggests that relationships between temperamental negative reactivity and adolescent depressive symptoms may be moderated by parental warmth. The primary purpose of this study was to conduct the first prospective analysis of this relationship.MethodData from 1,147 families in an Australian population-based longitudinal study were used to examine: (1) temporal relationships between negative reactivity in early adolescence (13–14 years) and depressive symptoms in emerging adulthood (19–20 years); (2) the moderating role of parent-reported warmth in early adolescence (13–14 years); and (3) the moderating role of child gender. Hierarchical multiple regression was conducted to test the hypothesis that parental warmth would moderate the relationship between early adolescent negative reactivity and depressive symptoms in emerging adulthood.ResultsAfter accounting for previous depressive symptoms at age 13–14 years, negative reactivity was positively associated with later depressive symptoms. By contrast, parental warmth at 13–14 years was negatively associated with later depressive symptoms for females but not males. Parental warmth did not moderate the association between early adolescent negative reactivity and subsequent depressive symptoms.ConclusionsThis study was the first to use prospective data to assess the protective effects of early adolescent parental warmth on the association between negative reactive temperaments and early adult depressive symptoms. Findings suggest that parental warmth for negatively reactive children provides only concurrent protection against subsequent depressive risk. This study did not examine parent–child transactional models, which may, in future longitudinal research, improve understanding of how trajectories of parent–child goodness-of-fit contribute to depressive symptoms.

Nurse-led group consultation intervention reduces depressive symptoms in men with localised prostate cancer: a cluster randomised controlled trial

BACKGROUND: Radiotherapy for localised prostate cancer has many known and distressing side effects. The efficacy of group interventions for reducing psychological morbidity is lacking. This study investigated the relative benefits of a group nurse-led intervention on psychological morbidity, unmet needs, treatment-related concerns and prostate cancer-specific quality of life in men receiving curative intent radiotherapy for prostate cancer.

METHODS: This phase III, two-arm cluster randomised controlled trial included 331 men (consent rate: 72 %; attrition: 5 %) randomised to the intervention (n = 166) or usual care (n = 165). The intervention comprised four group and one individual consultation all delivered by specialist uro-oncology nurses. Primary outcomes were anxious and depressive symptoms as assessed by the Hospital Anxiety and Depression Scale. Unmet needs were assessed with the Supportive Care Needs Survey-SF34 Revised, treatment-related concerns with the Cancer Treatment Scale and quality of life with the Expanded Prostate Cancer Index -26. Assessments occurred before, at the end of and 6 months post-radiotherapy. Primary outcome analysis was by intention-to-treat and performed by fitting a linear mixed model to each outcome separately using all observed data.

RESULTS: Mixed models analysis indicated that group consultations had a significant beneficial effect on one of two primary endpoints, depressive symptoms (p = 0.009), and one of twelve secondary endpoints, procedural concerns related to cancer treatment (p = 0.049). Group consultations did not have a significant beneficial effect on generalised anxiety, unmet needs and prostate cancer-specific quality of life.

CONCLUSIONS: Compared with individual consultations offered as part of usual care, the intervention provides a means of delivering patient education and is associated with modest reductions in depressive symptoms and procedural concerns. Future work should seek to confirm the clinical feasibility and cost-effectiveness of group interventions.