Calorimetric Behavior of Phosphatidylcholine/Phosphatidylethanolamine Bilayers is Compatible with the Superlattice Model

Differential scanning calorimetry was used to study the phase behavior of binary lipid bilayers consisting of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) of varying acyl chain length. A two-state transition model was used to resolve the individual transition components, and the two-state transition enthalpy, the relative enthalpy, and the transition temperature of each component were plotted as a function of composition. Intriguingly, abrupt changes in these thermodynamic parameters were observed at or close to many “critical” XPE values predicted by the superlattice model proposing that phospholipids with different headgroups tend to adopt regular rather than random lateral distributions. Statistical analysis indicated that the agreement between the observed and predicted “critical” compositions is highly significant. Accordingly, these data provide strong evidence that the molecules in PC/PE bilayers tend to adopt regular, superlattice-like lateral arrangements, which could be involved in the regulation of the lipid compositions of biological membranes

Measurement report : Introduction to the HyICE-2018 campaign for measurements of ice-nucleating particles and instrument inter-comparison in the Hyytiala boreal forest

The formation of ice particles in Earth's atmosphere strongly influences the dynamics and optical properties of clouds and their impacts on the climate system. Ice formation in clouds is often triggered heterogeneously by ice-nucleating particles (INPs) that represent a very low number of particles in the atmosphere. To date, many sources of INPs, such as mineral and soil dust, have been investigated and identified in the low and mid latitudes. Although less is known about the sources of ice nucleation at high latitudes, efforts have been made to identify the sources of INPs in the Arctic and boreal environments. In this study, we investigate the INP emission potential from high-latitude boreal forests in the mixed-phase cloud regime. We introduce the HyICE-2018 measurement campaign conducted in the boreal forest of Hyytiala, Finland, between February and June 2018. The campaign utilized the infrastructure of the Station for Measuring Ecosystem-Atmosphere Relations (SMEAR) II, with additional INP instruments, including the Portable Ice Nucleation Chamber I and II (PINC and PINCii), the SPectrometer for Ice Nuclei (SPIN), the Portable Ice Nucleation Experiment (PINE), the Ice Nucleation SpEctrometer of the Karlsruhe Institute of Technology (INSEKT) and the Microlitre Nucleation by Immersed Particle Instrument (mu L-NIPI), used to quantify the INP concentrations and sources in the boreal environment. In this contribution, we describe the measurement infrastructure and operating procedures during HyICE-2018, and we report results from specific time periods where INP instruments were run in parallel for inter-comparison purposes. Our results show that the suite of instruments deployed during HyICE-2018 reports consistent results and therefore lays the foundation for forthcoming results to be considered holistically. In addition, we compare measured INP concentrations to INP parameterizations, and we observe good agreement with the Tobo et al. (2013) parameterization developed from measurements conducted in a ponderosa pine forest ecosystem in Colorado, USA.Peer reviewe

Measurement report : Introduction to the HyICE-2018 campaign for measurements of ice-nucleating particles and instrument inter-comparison in the Hyytiala boreal forest

The formation of ice particles in Earth's atmosphere strongly influences the dynamics and optical properties of clouds and their impacts on the climate system. Ice formation in clouds is often triggered heterogeneously by ice-nucleating particles (INPs) that represent a very low number of particles in the atmosphere. To date, many sources of INPs, such as mineral and soil dust, have been investigated and identified in the low and mid latitudes. Although less is known about the sources of ice nucleation at high latitudes, efforts have been made to identify the sources of INPs in the Arctic and boreal environments. In this study, we investigate the INP emission potential from high-latitude boreal forests in the mixed-phase cloud regime. We introduce the HyICE-2018 measurement campaign conducted in the boreal forest of Hyytiala, Finland, between February and June 2018. The campaign utilized the infrastructure of the Station for Measuring Ecosystem-Atmosphere Relations (SMEAR) II, with additional INP instruments, including the Portable Ice Nucleation Chamber I and II (PINC and PINCii), the SPectrometer for Ice Nuclei (SPIN), the Portable Ice Nucleation Experiment (PINE), the Ice Nucleation SpEctrometer of the Karlsruhe Institute of Technology (INSEKT) and the Microlitre Nucleation by Immersed Particle Instrument (mu L-NIPI), used to quantify the INP concentrations and sources in the boreal environment. In this contribution, we describe the measurement infrastructure and operating procedures during HyICE-2018, and we report results from specific time periods where INP instruments were run in parallel for inter-comparison purposes. Our results show that the suite of instruments deployed during HyICE-2018 reports consistent results and therefore lays the foundation for forthcoming results to be considered holistically. In addition, we compare measured INP concentrations to INP parameterizations, and we observe good agreement with the Tobo et al. (2013) parameterization developed from measurements conducted in a ponderosa pine forest ecosystem in Colorado, USA.Peer reviewe

Physicians' knowledge of and adherence to improving oral health

Peer reviewe

Association between smoking intensity and duration and tooth loss among Finnish middle-aged adults:the Northern Finland Birth Cohort 1966 Project

Abstract Background: Smoking is a risk factor for oral diseases and tooth loss. Our aim was to analyze the association between smoking intensity and duration and tooth loss among middle-aged Finnish adults who have enjoyed access to subsidized dental care since childhood. Methods: This study was based on the Northern Finland Birth Cohort 1966 (NFBC1966) Project, a representative sample of Finnish 46-year-olds. Altogether 1946 46-year-olds participated in a survey and comprehensive clinical oral examinations. We measured smoking exposure in pack-years (intensity) and years of smoking (duration) combined with recent smoking status (current, former, occasional or never). We used negative binomial regression models to estimate the unadjusted and adjusted relative risks (RR) with corresponding 95 % confidence intervals (CI) for tooth loss as an outcome. Gender, education, tooth brushing frequency, dental plaque, diabetes and alcohol use served as explanatory variables for the adjusted models. Results: Smoking intensity associated with tooth loss in an exposure-dependent manner: those with a high number of pack-years had a significantly greater probability of tooth loss than never smokers: 11–20 pack-years (RR = 1.55, 95 % CI = 1.15–2.08) and 21 or more pack-years (RR = 1.78, 95 % CI = 1.36–2.33). Smoking duration also associated with tooth loss: those who had smoked for several years had a significantly higher probability of tooth loss than never smokers: 21–30 years of smoking (RR = 1.66, 95 % CI = 1.29–2.12) and 31 or more years of smoking (RR = 1.72, 95 % CI = 1.20–2.45). Conclusions: We found a clear intensity- and duration-dependent relation between smoking and tooth loss among adults with access to subsidized dental care and in good oral health

Psychological distress, dental health, and dental fear among Finnish university students:a national survey

Abstract The aim of this study was to investigate the association between dental fear, psychological distress, and perceived symptoms of teeth controlled for age, gender, educational sector, and tobacco use. The data from the Finnish University Student Health Survey 2016 targeting students (n = 10,000) of academic universities and universities of applied sciences were used. Psychological distress was measured with the Clinical Outcomes in Routine Evaluation 10 (CORE-10) and the General Health Questionnaire 12 (GHQ-12) and dental fear with the question ‘Do you feel scared about receiving dental care?’. The study included 3110 students. In logistic regression analyses those with psychological distress (measured with CORE-10 and GHQ-12) and those reporting teeth-related symptoms were more likely than their counterparts to have high dental fear. In gender-specific analyses men with psychological distress (measured with CORE-10) and women with teeth-related symptoms were more likely to have high levels of dental fear. Finnish university students with psychological distress and teeth-related symptoms were more likely to experience higher levels of dental fear than their counterparts were. The results of this study support possible common vulnerability factors that dental fear and other psychological disorders may share