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The present study explores the concurrent contribution to sleep problems of individual-related, family-related, and school-related factors in adolescence. Gathering from the Italian 2018 Health Behavior in School-Aged Children (HBSC) data collection, we used hierarchical logistic regression on a sample of 3397 adolescents (51% females, Mage = 13.99, SD = 1.62) to explore the contribution to sleep problems of the individual (Model 1: alcohol use, smoking, screen time, physical activity), familial (Model 2: parental communication, parental support), and school-related (Model 3: peer support, schoolmates/students support, teacher support and school pressure) variables. 28.3 percent of adolescents reported having sleep difficulties. Overall, Model 3 significantly improved over Model 2 and Model 1. Data showed that increasing smoking (OR = 1.11; 95% CI: 1.03–1.20) and screen time (OR = 1.05; 95% CI: 1.02–1.08) were associated with sleep difficulties but not alcohol use and physical activity. Also, impaired communication with both parents and increasing parental support (OR = 0.84; 95% CI: 0.78–0.90) were associated with decreased odds of sleep problems. Finally, both increases in school pressure (OR = 1.40; 95% CI: 1.26–1.56) and lack of student support (OR = 1.25; 95% CI: 1.10–1.42) were associated with a higher likelihood of sleep problems, while peer support and teacher support were not. Conclusion: Our findings highlight the importance of an integrated approach to the study of sleep difficulties in adolescence that includes specific psychosocial contributors such as the quality of parental communication and perceived parental support and considers the quality of the day-to-day relationship with schoolmates and the school level of demands.What is Known:• Adolescents' are at-risk of more significant sleep difficulties, and recent literature highlights the importance of an integrated approach to understanding this phenomenon, including biological, psychosocial, and contextual factors.• The literature lacks findings that consider the concurrent contribution of individual and psychosocial factors to sleep difficulties in adolescence.What is New:• The quality of parental communication and perceived parental support, as expressions of adult figures' emotional and behavioural availability in the adolescent's life, are significant determinants of sleep difficulties.• The quality of day-to-day relationships with schoolmates and the school level of demands contribute to adolescent sleep problems.

Background. Discussion on the impact of pocket money on positive behaviors is still debated.Objective. To investigate the effect of diverse money allowance schemes on risky behaviors (smoking, alcohol, binge drinking, drug use, gambling) during adolescence.Method. 989 students aged 15 from Lombardy (Italy) reported information on money availability in the 2018 wave of the Health Behaviour in School-aged Children study. To analyze the relationship between money availability and risky behaviors we computed odds ratios and 95% confidence intervals through unconditional multiple logistic regression models.Results. Spending more than 10(sic) weekly was associated with higher likelihood to smoke, binge drink or gamble. Receiving pocket money (rather than receiving money upon request) was related to higher likelihood to engage in risky behaviors.Conclusions. Pocket money may have a negative impact on adolescents, particularly with a substantial amount of money. More research is needed to understand why providing money only if needed may serve as a protective factor against risky behaviors.

Decays of pseudoscalar mesons proceed from the chiral anomaly, which arises from spontaneous chiral symmetry breaking. In the limit of massless quarks (chiral limit), the η → π +π −γ the decay width is determined solely by the box anomaly term in the Wess Zumino Witten Lagrangian. Since the physical quarks are not massless, the decay region of the η meson is far from the chiral limit and thus proper inclusion of the momentum dependence is essential to reproduce the measured decay width. Several theoretical frameworks have been proposed to describe these interactions. We report a new measurement of the α parameter which measures the contribution of pion-pion final state interactions to the differential decay width. The data was collected during the g11a run period using the CEBAF Large Acceptance Spectrometer located in Hall B at the Thomas Jefferson National Accelerator Facility in 2004. The data was collected using a tagged photon beam with energy range of 1.5-3.5 GeV incident on a liquid Hydrogen target. Our results are in agreement with the latest experimental measurement and theoretical calculations

Specificity of small ions, the Hofmeister ranking, is long-known and has many applications including medicine. Yet it evades consistent theoretical description. Here we study the effect of Hofmeister anions on gramicidin A channels in lipid membranes. Counterintuitively, we find that conductance of this perfectly cation-selective channel increases about two-fold in the H2 PO4

Among the different types of biomass, microalgae have the potential of becoming an important energy source in the future, and hydrothermal liquefaction (HTL) appears as a promising technology for that purpose. It produces an organic liquid energy carrier, usually called biocrude oil, together with gas, aqueous and solid phases. The complex phenomena occurring during the process, as well as the influence of the type of microalgae, are not fully understood. This work aimed to study how different strain­specific parameters (i.e. biochemical composition, cell structure or growth medium) affect the HTL biocrude oil production, in order to suggest the best strains for this process. Most of the studies available on microalgae HTL have reported just a phenomenological description of the biocrude yields obtained. In this work, deeper studies were carried out, focusing on its composition. For that reason, stepwise Py­GC/MS was coupled with Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA), allowing to characterize a large fraction of the biocrude oil., Proceedings of the 21st European Biomass Conference and Exhibition, 3-7 June 2013, Copenhagen, Denmark, pp. 1318-1322

Interactions of lipid membranes and macromolecules in general depend on the pH of buffered solutions. However, pH buffers modify molecular interactions in more than one way [1,2]. Here we conduct in vitro experiments with mammalian and bacterial cells to determine how common buffers such as 3-(N-morpholino)propanesulfonic acid (MOPS) affect cell viability. We find that primary rat lung microvascular cells do not survive in concentrations greater than 125mM for MOPS compared to 40mM for KCl, and 50mM for PEG400. In contrast, E. coli cells survived in concentrations up to 0.75 M for KCl and 1M MOPS. This is ascribed to a protective effect from the bacterial cell wall. Results are interpreted by comparison with previous measurements of model membrane interactions in buffer solutions.[1] Koerner et al., Biophys. J. 101, 2011.[2] Peiro-Salvador et al. Biochemistry, 48, 2009.[3] van Haaren et al., Am. J. Physiol. Heart Circ. Physiol., 289, 2005.

Nowadays only little information (mainly by GC­MS) about the chemical nature of HTL oils is available. In the present work different standard and improved analytical techniques were tested as additional tools for the chemical characterization of HTL oils: analytical pyrolysis (Py­GC­MS), TGA and a novel stepwise Py­SPME­GC­MS were tested for the first time. By coupling these different techniques, we could establish the chemical nature of the fractions not amenable for standard oil analysis techniques (GC­MS, silylation or transesterification). In the case of 200°C HTL the high molecular weight substances mainly consisted in algaenans derived materials, whereas a low amount of proteins (or protein containing macromolecules) ended up in the HTL oil. In the case of 300°C HTL oil, the mass fraction of the HTL products originated from non­lipidic material degradation as well as “protein” content of the oil were identified and the resulting high nitrogen content present in the 300°C HTL oil was explained., Proceedings of the 19th European Biomass Conference and Exhibition, 6-10 June 2011, Berlin, Germany, pp. 134-141

The exploitation of aquatic biomass for energetic purpose is a promising field of research. Chlamydomonas reinhardtii is a deeply investigated microalga able to convert sunlight into chemical energy by indirect photolysis under specific culture conditions, allowing the production of a hydrogen rich biogas and algal biomass as side-product. Besides the hydrogen production, a valorisation of “spent” side-products is a key point for the process optimization, for the maximization of process energetic yield and the reduction of photo-biogenic hydrogen prices. The aim of this work was to investigate the potential conversion of Chlamydomonas reinhardtii exhaust biomass to bio-diesel, pyrolysis oil and nitrogen rich charcoal (bio-char). Microalgal fats were obtained through a standard extraction (15% wlipids/wbiomass yield). Then, the extraction residue, mainly characterised by proteins and cellulose, was pyrolysed at 350°C using a bench scale pyrolyser, in order to convert the raw biomass into bio-oil and bio-char. The major pyrolysis product resulted to be bio-char (45% mass yield), whereas a lower amount of pyrolysis oil (25% mass yield) was obtained. Bio-oil was mainly formed by cellulose pyrolysis products (55% w/wbio-oil mainly anhydrosugars, anhydro-oligomers and small polysaccharides). On the other hand the feedstock proteins played the most important role in bio-char formation., Proceedings of the 18th European Biomass Conference and Exhibition, 3-7 May 2010, Lyon, France, pp. 455-458

Analytical pyrolysis was applied to investigate the composition of pyrolysate from seven switchgrass samples differing in cytotype and cutting systems. The content of ash in original samples ranged from 3.2 to 6.4%, cellulose from 31 to 44% , lignin from 3.5 to 8.7%. Pyrolyses were conducted at 700 °C with a microscale pyrolysis apparatus (pyroprobe) and evolved products were analysed by GC-MS (lignin phenols, C5-C6 carbohydrate fragments), GC-MS after trimethylsilylation (levoglucosan) and GC-FID (acetic acid, propionic acid, acetol). Pyrolysates of all the samples were dominated by acetic acid (3.7-5.2%), acetol, 0.9-1.5%, 4-vinylphenol (0.3-1.2%), 4-vinylguaiacol (0.2-0.5%) and levoglucosan (0.2-2%). Yields of total quantified products (18 compounds) ranged from 7 to 11% and tended to increase with increasing lignocellulose and decreasing ash content., Proceedings of the 18th European Biomass Conference and Exhibition, 3-7 May 2010, Lyon, France, pp. 477-479

Gramicidin A (gA) is a cation selective ion channel that has been used in many biophysical studies of lipid bilayers, in particular for investigations of lipid-protein interactions [1, 2] and membrane electrostatics [3]. In addition, it was found that ionic interactions with neutral lipid membranes also affect the kinetics of gA channels [4]. Here we report measurements of gA ion-channels for a series of sodium and potassium salts that show an anion-dependence of gA conductance. We find that gA conductance varies significantly with the anion type with ClO4 and SCN producing distinctly larger conductance values than Cl, F, and H2PO4. These results can provide new insights into ion-lipid membrane interactions and ion channel functions in general. [1] Andersen et al., Annu. Rev. Biophys. Biomol. Struct., 1996, [2] Lunbaek et al., PNAS 2010, [3] Rostovtseva et al. Biophys. J. 1998, [4] Rostovtseva et al. Biophys. J. 2008.

Resistance to oxidative damage is an important feature of cancer cells. Cellular anti-radical enzymes, lipid peroxidation, glutathione pathway, capability to produce ROS, and cells' susceptibility to H2O2 and menadione toxicity, were analyzed in DND-1A and HeLa cancer cell lines. SOD and GSHPx activities were higher in DND-1A than in HeLa cells. Lipid peroxidation was the same in both cell lines, while menadione stimulation of ROS production was tenfold higher in HeLa cells. Total and reduced, but not oxidized, glutathione levels, were tenfold smaller in HeLa cells. H2O2 proved fatal to HeLa cells after 12 hours' incubation, while it was ineffective on DND-1A; DND-1A cells were more sensitive to menadione toxicity than HeLa cells. The two lines behaved differently in response to the above treatments. These observations might be important in designing more specific cancer treatments.

Lithium is a naturally occurring alkali metal which is very easily ionized to Li+, especially in aqueous solutions. Lithium is found mainly in mineral and seawater and in trace amounts in the human body. Lithium ions are being used in various fields ranging from energy storage to the treatment of mental illnesses including bipolar disorder and schizophrenia. The reason why lithium is such a peculiar ion is not exactly known except that its mode of interactions with charged surfaces depends on its hydration properties (i.e. interaction with nearby water molecules). We report two kinds of experimental measurements of lithium interactions with charged lipid membranes. One set of experiments involves X-ray scattering of multilamellar lipid vesicles in solution for which we measure how lithium salts modify van der Waals and electrostatic forces between neighboring membranes. The other set of measurements compare the effect of added lithium on the activity of gramicidin channels in neutral and negatively charged lipid bilayers. We find that in both x-ray and channel measurements, lithium ions modify lipid interactions in a manner that differs from other monovalent posititive ions.

Specific ionic effects, as captured in the Hofmeister series, have been observed in many biological phenomena including protein folding and aggregation and lipid bilayer interactions. Previously we have shown that the Hofmeister effect is present in the activity of gramicidin A channels. In particular, measurements of channel open lifetime and conductance in potassium salts clearly show the existence of two distinct ionic classes which could be identified as kosmotropic and chaotropic. To further investigate this behavior, we have measured the zeta potential of diphytanoyl phosphatidylcholine (DPhPC) liposomes in salt solutions. We observe that anions alter the surface charge of the liposomes depending on the classification of the anion as kosmotropic or chaotropic. Chaotropic anions (SCN-, ClO4-) decrease the surface charge of the liposomes while kosmotropic anions (Cl-, H2PO4-, SO42-) have the opposite effect. These results correlate with our previous studies of cation conductance through gramicidin A channels adding new insight into ionic interactions at the lipid-water interface.