Effects of Sex, Age and Height on Symphysis-Ischial Spine Distance Measured on a Pelvic CT.

OBJECTIVE: To examine the influence of age, sex and height on the symphysis-ischial spine distance (SID) measured on pelvic Computed tomography (CT)images in subjects of reproductive age, and to determine the interobserver reproducibility. This measurement (SID) is of great importance because the use of intrapartum ultrasound is based on the assumption of a specific value (30 mm) of such a measurement. METHODS: This was a cross-sectional descriptive study in which SID was measured in subjects aged 20 to 44 years who had been scheduled for pelvic CT at our centre from January 2018 to May 2021 for different reasons. Radiographic measurements of the pelvis were obtained through the multiplanar reconstruction of the CT image. The images obtained from all of the participants were independently assessed by three senior radiologists, and the SID measurements made by each one were blinded from those of the remaining observers. Correlations between the SID and patient age, height and sex were analyzed by univariate and multivariate linear regression. RESULTS: The mean SID for 87 of the enrolled participants (45 women, 42 men) was 28.2 ± 6.25 mm. Among the observers, the mean difference in this distance was 1 to 2 mm, and was scarcely related to measurement size, with agreement being greater than 70%. The mean SID was significantly related to sex and height (SID = -24.9 - 6.51 × sex (0 or 1) + 0.34 × height (cm); p = 0.01; sex equals 1 for a man and 0 for a woman), such that it was a mean of 2.5 mm greater in women than men (29.50 mm vs. 26.99 mm). CONCLUSION: Measurements of SID on CT images show good interobserver reproducibility, and are related to sex and height.

Temperature or competition: Which has more influence on Mediterranean ant communities?

Temperature and competition are two of the main factors determining ant community assemblages. Temperature may allow species to forage more or less efficiently throughout the day (in accordance with the maximum activity temperature of each species). Competition can be observed and quantified from species replacements occurring during resource exploitation. We studied the interspecific competitive interactions of ant communities from the Doñana Biological Reserve (southern Spain). Ants were sampled from pitfall traps and baits in three habitats with contrasted vegetation physiognomy (savin forest, pine forest, and dry scrubland). We measured the temperature during the competitive interactions between species and created a thermal competition index (TCI) to assess the relative contribution of temperature and numerical dominance to the competitive outcomes. Temperature had unequal effects on ant activity in each type of habitat, and modulated competitive interactions. The TCI showed that a species' success during pair interactions (replacements at baits) was driven by the proportion of workers between the two competing species and by the species-specific effect of temperature (how advantageous the temperature change is for each species during bait replacement). During competitive interactions, the effect of temperature (higher values of TCI) and numeric supremacy (higher worker proportion) gave higher success probabilities. Interspecific competitive relationships in these Mediterranean ant communities are habitat dependent and greatly influenced by temperature.

Analysing natural ventilation to reduce the cooling energy consumption and the fuel poverty of social dwellings in coastal zones.

In southern European countries, summer temperatures could contribute to a high cooling energy consumption. Family units with fewer economic resources living in social dwellings could suffer from fuel poverty if they want to use air conditioning systems. Otherwise, they could face discomfort hours because of a natural ventilation without clear control criteria. This study analyses quantitatively and qualitatively the possibilities of natural ventilation through mixed-mode and the possibility of reducing fuel poverty for family units living in social dwellings. For this purpose, the application of a natural ventilation approach was analysed through an adaptive behaviour based on EN 16798-1: 2019. A case study of 51 social dwellings was analysed by using various operation hypothesis between 2015 and 2019. The results showed the potential of using mixed-mode approaches based on the categories from EN 16798-1:2019 to achieve savings in the energy consumption and to remove cases of fuel poverty in low-income families. Likewise, surveys in which families living in these cities participated reflected the great awareness of the natural ventilation use, although there is not a clear criterion of the need of this ventilation for thermal comfort, as well as the need of a supportive use of air conditioning systems. Finally, the similarity of the climate conditions of the city analysed and the coastal cities from various countries in the south of Europe shows the possibility of using ventilation strategies as energy saving measures in other regions.