Adolescents with cystic fibrosis (CF) often face a unique set of difficulties and challenges as they transition to adulthood and autonomy while also managing a progressive illness with a heavy ...treatment burden. Coping styles have been related to changes in physical health among youth with chronic illness more generally, but the directionality of these links has not been fully elucidated. Therefore, the objective of this study was to evaluate bidirectional links between coping styles and physical health indicators among adolescents with CF over time.
Adolescents (N = 79, 54% female) recruited from inpatient and outpatient CF clinics at two sites completed questionnaires assessing secular and religious/spiritual coping styles at two time points (18 months apart, on average). Health indicators including pulmonary functioning, nutritional status, and days hospitalized were obtained from medical records.
More frequent hospitalizations predicted lower levels of adaptive secular coping over time. However, poorer pulmonary functioning predicted higher levels of positive religious/spiritual coping. The number of days hospitalized was related to adaptive secular coping and negative religious/spiritual coping.
Among youth with CF, physical health functioning is more consistent in predicting coping strategies than the reverse. Poorer pulmonary functioning appears to enhance adaptive coping over time, suggesting resilience of adolescents with CF, while more frequent hospitalizations may inhibit the use of adaptive coping strategies. Findings support the use of interventions aimed at promoting healthy coping among hospitalized adolescents with CF.
Context.
The origin of the reservoirs of water on Earth is debated. The Earth’s crust may contain at least three times more water than the oceans. This crust water is found in the form of ...phyllosilicates, whose origin probably differs from that of the oceans.
Aims.
We test the possibility to form phyllosilicates in protoplanetary disks, which can be the building blocks of terrestrial planets.
Methods.
We developed an exploratory rate-based warm surface chemistry model where water from the gas-phase can chemisorb on dust grain surfaces and subsequently diffuse into the silicate cores. We applied the phyllosilicate formation to a zero-dimensional chemical model and to a 2D protoplanetary disk model (P
RO
D
I
M
O
). The disk model includes in addition to the cold and warm surface chemistry continuum and line radiative transfer, photoprocesses (photodissociation, photoionisation, and photodesorption), gas-phase cold and warm chemistry including three-body reactions, and detailed thermal balance.
Results.
Despite the high energy barrier for water chemisorption on silicate grain surfaces and for diffusion into the core, the chemisorption sites at the surfaces can be occupied by a hydroxyl bond (–OH) at all gas and dust temperatures from 80 to 700 K for a gas density of 2 × 10
4
cm−3. The chemisorption sites in the silicate cores are occupied at temperatures between 250 and 700 K. At higher temperatures thermal desorption of chemisorbed water occurs. The occupation efficiency is only limited by the maximum water uptake of the silicate. The timescales for complete hydration are at most 10
5
yr for 1 mm radius grains at a gas density of 10
8
cm
−3
.
Conclusions.
Phyllosilicates can be formed on dust grains at the dust coagulation stage in protoplanetary disks within 1 Myr. It is however not clear whether the amount of phyllosilicate formed by warm surface chemistry is sufficient compared to that found in Solar System objects.
This study describes the capabilities and limitations of carrying out total scattering experiments on the Powder Diffraction (PD) beamline at the Australian Synchrotron, ANSTO. A maximum instrument ...momentum transfer of 19 Å−1 can be achieved if the data are collected at 21 keV. The results detail how the pair distribution function (PDF) is affected by Qmax, absorption and counting time duration at the PD beamline, and refined structural parameters exemplify how the PDF is affected by these parameters. There are considerations when performing total scattering experiments at the PD beamline, including (1) samples need to be stable during data collection, (2) highly absorbing samples with a μR > 1 always require dilution and (3) only correlation length differences >0.35 Å may be resolved. A case study comparing the PDF atom–atom correlation lengths with EXAFS‐derived radial distances of Ni and Pt nanocrystals is also presented, which shows good agreement between the two techniques. The results here can be used as a guide for researchers considering total scattering experiments at the PD beamline or similarly setup beamlines.
Total scattering data can be obtained on the PD beamline although there are constraints to the capabilities offered including longer acquisition times and necessary dilution of highly absorbing samples. This work details the considerations needed to successfully carry out total scattering studies on this bending‐magnet beamline, which has not been specifically designed for total scattering experiments.
The initial decoupling of the (6√3×6√3)R30° buffer layer also called zero layer graphene (ZLG) on 6H-SiC(0001) by Si intercalation has been investigated by means of high resolution photoemission ...spectroscopy (HRPES) and microscopy imaging techniques. A combination of complementary techniques has shown that the annealing above 700°C of amorphous Si deposited on ZLG leads to the diffusion of the silicon over the surface. Two competing processes are then observed. Part of the silicon contributes to a progressive decoupling of the ZLG from the substrate (partial decoupling) while the rest agglomerates at the surface to form oriented silicon clusters. After sequences of Si deposition, followed by annealing at 750°C, complete decoupling is observed into quasi-free standing monolayer (ML) graphene. Investigation of the evolution of the C1s and Si2p core levels during the intermediate states shows that the appearance of the graphene contribution coincides with the creation of an extra SiC bulk component, indicating their electronic decoupling. At partial decoupling of the ZLG, we have the coexistence of structurally linked metal-semiconducting materials presenting mutual electronic interactions and composed of nanometric metal-semiconducting heterojunctions.
Hydrogen was produced by aqueous‐phase reforming (APR) of sorbitol in a carbon‐on‐alumina tubular membrane reactor (4 nm pore size, 7 cm long, 3 mm internal diameter) that allows the hydrogen gas to ...permeate to the shell side, whereas the liquid remains in the tube side. The hydrophobic nature of the membrane serves to avoid water loss and to minimize the interaction between the ceramic support and water, thus reducing the risks of membrane degradation upon operation. The permeation of hydrogen is dominated by the diffusivity of the hydrogen in water. Thus, higher operation temperatures result in an increase of the flux of hydrogen. The differential pressure has a negative effect on the flux of hydrogen due to the presence of liquid in the larger pores. The membrane was suitable for use in APR, and yielded 2.5 times more hydrogen than a reference reactor (with no membrane). Removal of hydrogen through the membrane assists in the reaction by preventing its consumption in undesired reactions.
Tubular shells: Hydrogen is selectively produced by means of aqueous‐phase reforming in a hydrophobic tubular membrane reactor. The hydrogen gas permeates to the shell side, whereas the liquid remains in the tube side. The removal of hydrogen through the membrane prevents its consumption in undesired reactions, increasing the yield of hydrogen.
Surveillance for hepatocellular carcinoma (HCC) is recommended in patients with cirrhosis. As α-fetoprotein (AFP) is considered a poor surveillance test, we tested the performance of its changes over ...time.
Eighty patients were diagnosed with HCC (cases) during semiannual surveillance with ultrasonography and AFP measurement were recruited and matched for age, gender, etiology and Child-Pugh class with 160 contemporary cancer-free controls undergoing the same surveillance training group (TG). As a validation group (VG) we considered 36 subsequent patients diagnosed with HCC, matched 1 : 3 with contemporary cancer-free controls. α-Fetoprotein values at the time of HCC diagnosis (T0) and its changes over the 12 (Δ12) and 6 months (Δ6) before cancer detection were considered.
In both TG and VG, >80% of HCCs were found at an early stage. In TG, AFP significantly increased over time only in cases. T0 AFP and a positive Δ6 were independently associated with HCC diagnosis (odds ratio: 1.031 and 2.402, respectively). The area under the curve of T0 AFP was 0.76 and its best cutoff (BC) was 10 ng ml(-1) (sensitivity 66.3%, specificity 80.6%). The combination of AFP >10 ng ml(-1) or a positive Δ6 composite α-fetoprotein index (CAI) increased the sensitivity to 80% with a negative predictive value (NPV) of 86.2%. Negative predictive value rose to 99%, considering a cancer prevalence of 3%. In the VG, the AFP-BC was again 10 ng ml(-1) (sensitivity 66.7%, specificity 88.9%), and CAI sensitivity was 80.6% with a NPV value of 90.5%.
CAI achieves adequate sensitivity and NPV as a surveillance test for the early detection of HCC in cirrhosis.
Aging is a major risk factor for developing postoperative cognitive dysfunction. Neuroinflammatory processes, which can play a causal role in the etiology of postoperative cognitive dysfunction, are ...potentiated or primed as a function of aging. Here we explored whether exposure to a microorganism with immunoregulatory and anti-inflammatory properties, Mycobacterium vaccae NCTC 11659 (M. vaccae), could ameliorate age-associated neuroinflammatory priming. Aged (24 months) and adult (3 months) male F344XBN rats were immunized with heat-killed M. vaccae (3 injections, once per week) before undergoing a laparotomy or anesthesia control procedure. Aged, but not young rats, showed postoperative learning/memory deficits in a fear-conditioning paradigm. Importantly, M. vaccae immunization protected aged rats from these surgery-induced cognitive impairments. M. vaccae immunization also shifted the aged proinflammatory hippocampal microenvironment toward an anti-inflammatory phenotype. Furthermore, M. vaccae immunization reduced age-related hyperinflammatory responses in isolated hippocampal microglia. Overall, our novel data suggest that M. vaccae can induce an anti-inflammatory milieu in the aged brain and thus mitigate the neuroinflammatory and cognitive impairments induced by surgery.
Abstract To investigate the effects of posture and gender on thoraco-abdominal motion and breathing pattern, 34 healthy men and women were studied by Opto-Electronic Plethysmography during quiet ...breathing in five different postures from seated (with and without back support) to supine position. Chest wall kinematics and breathing pattern were significantly influenced by position and gender. The progressively increased inclination of the trunk determined a progressive reduction of rib cage displacement, tidal volume, and minute ventilation and a progressive increase of abdominal contribution to tidal volume. Female subjects were characterized by smaller dimensions of the rib cage compartment and during quiet breathing by lower tidal volume, minute ventilation and abdominal contribution to tidal volume than males. The effect of posture on abdominal kinematics was significant only in women. The presence of a back support in seated position determined differences in breathing pattern. In conclusion, posture and gender have a strong influence on breathing and on chest wall kinematics.
The evolution of the filamentation instability produced by two counterstreaming, ultrarelativistic pair plasmas is studied with particle-in-cell simulations. Radiation friction effects are taken into ...account. Two-dimensional simulations are performed for both cases of the initial momenta being perpendicular (T mode) or parallel (P mode) to the simulation plane. In the initial stage, the instability is purely transverse for both modes and generates small-scale filaments which later merge into larger structures. Particle acceleration leads to a strong broadening of the energy spectrum with the formation of a peak at twice the initial energy for the T mode. In the non-linear stage, significant differences between T- and P modes in the evolution of the fields and in the spectra of accelerated particles are apparent. The presence of radiative losses does not change the dynamics of the instability but strongly affects the structure of the particle spectra in the ultrarelativistic regime (particle energy >100 MeV) and for high plasma densities (>1021 cm−3).
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