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We investigated the links between peritraumatic distress in children and in their parents following a potentially traumatic event, focusing specifically on the role that parents and family functioning can play in the development and maintenance of post-traumatic disorders in children. To this end, we examined a population of 41 children (aged 8 and above), and their parents, who had been admitted to the emergency room of a pediatric hospital due to an accident. The design included a two-step assessment: immediate reactions (in the hours following the event) and delayed reactions (5–8 weeks after the event). We used six questionnaires to assess reactions. The results indicated a statistically significant positive correlation between the intensity of the peri-traumatic distress of the parents and the level of post-traumatic symptoms observed later (5 to 8 weeks after the event) in the questionnaires administered to the children. Regarding educational practices, differences appear to be linked to maternal education practice and to the severity of child's symptomatology. Finally, a link has been established between changes within the family dynamic after a potentially traumatic event and the severity of child's posttraumatic symptoms. This study showed the extent to which the parents’ initial reactions can be decisive in the outcome for a child who has experienced a potentially traumatic event. The study highlights the importance of assessing parental responses as well as paying attention to the children when they arrive in a pediatric emergency room. The results are relevant for prevention and treatment of PTSD in children, as the integration of this parental dimension early on in the process may lead to improved identification of which young patients are at risk of developing post-traumatic symptomatology.

We report the areal growth kinetics of fibrinogen adsorbed on model hydrophobic and hydrophilic surfaces measured via an adsorption probe method. This approach exploits the adsorption of probe molecules to determine the evolution of fibrinogen test molecules under conditions where the fibrinogen test molecules adsorb at relatively dilute surface conditions, minimizing interactions between them. It is found that fibrinogen test molecules spread from an average initial footprint of 100 nm² to a final footprint near 500 nm² per molecule on the hydrophobic surface, with a single-exponential decay of 1735 s. On a hydrophilic monolayer, the area increases from 100 to 160 nm² with a characteristic time of 6740 s. These results demonstrate the power of the adsorption probe approach and comprise the first measurements of the averaged area relaxations of adsorbed proteins. The observation of single-exponential dynamics is remarkable, given the extensive relaxation on the hydrophobic surface, which must involve fibrinogen denaturing.

Experimental data are presented for liquid−liquid equilibria of mixtures of the room-temperature ionic liquid 1-ethyl-3-methyl-imidazolium bis(trifluoromethylsulfonyl)imide ([C2MIM][NTf2]) with the three alcohols propan-1-ol, butan-1-ol, and pentan-1-ol and for the 1-butyl-3-methyl-imidazolium bis(trifluoromethylsulfonyl)imide ([C4MIM][NTf2]) with cyclohexanol and 1,2-hexanediol in the temperature range of 275 K to 345 K at ambient pressure. The synthetic method has been used. Cloud points at a given composition were observed by varying the temperature and using light scattering to detect the phase splitting. In addition, the influence of small amounts of water on the demixing temperatures of binary mixtures of [C2MIM][NTf2] and propan-1-ol, butan-1-ol, and pentan-1-ol was investigated.

Using total internal reflectance fluorescence (TIRF), we observe that lysozyme adsorption onto hydrophobic surfaces can exhibit kinetic overshoots at some conditions, while, at lower free solution concentrations or flow rates over the surface, the coverage monotonically approaches its final value. This behavior is explained by an interfacial relaxation from an end-on to a side-on orientation, which occurs by rollover and not by the displacement of end-on adsorbed proteins by side-on adsorbing proteins. Rollover and displacement models are compared with data to prove this point. Ultimately, we quantitatively predict the kinetic traces for a variety of different adsorption histories (free solution concentration, flow rate, interruption of adsorption by flowing solvent) using a rollover model with reversible transport-limited adsorption of end-on oriented lysozyme and a single rollover rate constant.

This work examined the relationship between footprint growth and adsorption energetics for fibrinogen on model hydrophobic and hydrophilic surfaces. For adsorption runs at different free solution concentrations and flow rates in a slit-shear flow cell, single surface-dependent relaxation times were found on each of two model surfaces. By use of each relaxation time in an exponential growth model, predictions of the footprint size distributions were made for different adsorption histories. Then, from desorption rate measurements and a reversible binding model, the sizes of loosely and tightly bound populations were determined, in addition to the binding energy of the loosely bound population. These binding energies were then compared with the footprint size distributions to reveal markedly different behavior on the hydrophobic and hydrophilic surfaces. On the hydrophobic surface, a single footprint size correlated with a binding energy of 6kT, a feature that was independent of adsorption history and the footprint size distribution. On the hydrophilic surface, the footprint size associated with a similar binding energy for the loosely bound population depended on the adsorption history. These observations are discussed in the context of potentially different relaxation mechanisms on the two surfaces.

This work compares the spreading and relaxation rates of albumin and fibrinogen, inferred from single-component and competitive adsorption kinetic experiments, on model surfaces of varying hydrophobicity. Kinetics from the single-component studies revealed a constant spreading rate, where the adsorbed protein footprint grew linearly in time for at least 15 min. This spreading rate increased with substrate hydrophobicity (ranging from 0.02 to 0.16 nm²/molecule/s for albumin and from 0.04 to 0.26 nm²/molecule/s for fibrinogen), resulting in a larger extent of footprint growth and a lower ultimate coverage on hydrophobic surfaces when compared with hydrophilic surfaces at the same adsorption conditions. Competitive adsorption studies were in qualitative agreement with the single-component experiments but were able to probe longer spreading time scales. Although spreading appeared to occur initially at a constant rate in the competitive experiments, after 2 h the spreading rate had slowed dramatically and the spreading process had begun to level off.

We report the kinetic behavior of albumin and fibrinogen adsorption and relaxation from gentle shearing flow and phosphate buffer onto C16 self-assembled monolayers. The adsorption kinetics were generally transport-limited; however, the ultimate coverages depended on the rates at which protein molecules arrived at the surface, suggesting that interfacial relaxations determined the ultimate coverage. Of particular note was a dependence of the ultimate coverage of both proteins on the wall shear rate, in addition to the influence of the bulk solution concentration. Analysis of single protein experiments revealed interfacial protein relaxation rates of 0.12 and 0.15 nm² molecule^-1 s^-1 for albumin and fibrinogen, respectively. These rates were constant over the range of experimental conditions and represent the initial relaxation rates after protein adhesion to the surface. The initial protein footprints were consistent with the free solution protein dimensions and, in the case of albumin, grew over a factor of 5 as the protein relaxed. For fibrinogen, relaxations were less extensive, increasing the footprint by a factor of 3. The extents of relaxation and the sizes of the protein footprints during the linear regime of spreading suggest that interfacial denaturing contributes significantly to the relaxation process, in addition to simple reorientations. The albumin relaxation behavior was shown, in addition to its influence on albumin coverage, to affect the coverage of fibrinogen in competitive situations. When the C16 layer was passivated with albumin prior to fibrinogen adsorption, short albumin exposures (still sufficient to cover the C16 surface) were ineffective at preventing fibrinogen adsorption. Prolonged incubation of albumin layers in albumin solution or buffer dramatically reduced subsequent fibrinogen adhesion.

This article reviews the progress made by AWWA over the past 40 years, from 1920‐1960. Statistics are given for membership, operating budgets, staff salaries, net receipts and disbursements for the years including 1920, 1930, 1940, and 1950. The growth of sections is discussed, along with control of activities, the Advancement Program, and the Aims and Objectives Committee.

An apparatus for measuring liquid−liquid equilibria of small samples of liquid mixtures with relatively high differences in density and viscosity was applied for studying mixtures of the ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide and the three alcohols propan-1-ol, butan-1-ol, and pentan-1-ol. The synthetic method has been applied where cloud points at a given composition were determined by varying the temperature. The point of phase splitting was detected by light scattering. Data in the temperature range 281 K to 340 K have been obtained for the three systems.

This article discusses the challenges of water supply in the United States, in particular the challenge of long‐range planning, the challenge of communicating to the public the need to provide for the water supply needs of the future growth of communities, and the challenge of providing quality water service, or quality service of quality water.