Structural ambiguity of the Chinese version of the hospital anxiety and depression scale in patients with coronary heart disease

Background The Hospital Anxiety and Depression Scale (HADS) is a widely used screening tool designed as a case detector for clinically relevant anxiety and depression. Recent studies of the HADS in coronary heart disease (CHD) patients in European countries suggest it comprises three, rather than two, underlying sub-scale dimensions. The factor structure of the Chinese version of the HADS was evaluated in patients with CHD in mainland China. Methods Confirmatory factor analysis (CFA) was conducted on self-report HADS forms from 154 Chinese CHD patients. Results Little difference was observed in model fit between best performing three-factor and two-factor models. Conclusion The current observations are inconsistent with recent studies highlighting a dominant underlying tri-dimensional structure to the HADS in CHD patients. The Chinese version of the HADS may perform differently to European language versions of the instrument in patients with CHD

Construct and content validity of the Greek version of the Birth Satisfaction Scale (G-BSS)

Background: ‘Birth Satisfaction’ is a term that encompasses a woman’s evaluation of her birth experience. The term includes factors such as her appraisal of the quality of care she received, a personal assessment of how she coped, and her reconstructions of what happened on that particular day. Her accounts may be accurate or skewed, yet correspond with her reality of how events unfolded. Objective: To evaluate properties of an instrument designed to measure birth satisfaction in a Greek population of postnatal women. Study design: We assessed factor structure, internal consistency, divergent validity and known-groups discriminant validity of the 30-item Greek Birth Satisfaction Scale – Long Form (30-item G-BSS-LF) and its revised version the 10-item Greek-BSS-Revised (10-item-G-BSS-R), using survey data collected in Athens. Participants: A convenience sample of healthy Greek postnatal women (n = 162) aged 22–46 years who had delivered between 34 and 42 weeks’ gestation. Results: The 30-item-G-BSS-LF performed poorly in terms of factor structure. The short-form 10-item-G-BSS-R performed well in terms of measurement replication of the English equivalent version as a multidimensional instrument. The short-form 10-item-G-BSS-R comprises three subscales which measure distinct but correlated domains of: (1) quality of care provision (4 items), (2) women’s personal attributes (2 items), and (3) stress experienced during labour (4 items). Key conclusions: The 10-item-G-BSS-R is a valid and reliable multidimensional psychometric instrument for measuring birth satisfaction in Greek postnatal women

Analysis and prediction of VH/VL packing in antibodies

The packing of VH and VL domains in antibodies can vary, influencing the topography of the antigen-combining site. However, until recently, this has largely been ignored in modelling antibody structure. We present an analysis of the degree of variability observed in known structures together with a machine-learning approach to predict the packing angle. A neural network was trained on sets of interface residues and a genetic algorithm designed to perform ‘feature selection' to define which sets of interface residues could be used most successfully to perform the prediction. While this training procedure was very computationally intensive, prediction is performed in a matter of seconds. Thus, not only do we provide a rapid method for predicting the packing angle, but also we define a set of residues that may be important in antibody humanization in order to obtain the correct binding site topograph

The effect of SU-8 patterned surfaces on the response of the quartz crystal microbalance

In this work we present data showing the effect of patterning layers of SU-8 photoresist on a quartz crystal microbalance (QCM) and subsequent chemical treatment to increase their hydrophobicity. Patterns with 5 mu m diameter pillars spaced every 10 mu m have been fabricated with heights of 3, 5 and 10 mu m in addition to equivalent thickness flat layers. Contact angle measurements have been made before and after the hydrophobic chemical treatment. The change in resonant frequency of the QCM has been investigated as the surfaces were submerged in solutions of water/PEG with changing viscosity-density product

Quality of Life in a Mixed Ethnic Population after Myocardial Infarction

Background: Although South Asian people are a significant ethnic group at increased risk of coronary heart disease and high mortality rates and experience greater delays with respect to diagnosis, referral and treatment, comparatively little is known about their quality of life during recovery from a myocardial infarction.Objectives: We sought to determine and compare the impact of ethnicity on quality of life after myocardial infarction (MI) in a mixed ethnic population (South Asian and white people) in the UK.Methods: A 2x2 mixed-group design with repeated measures on the second factor. The independent variables were ethnic group (white/South Asian) and time since MI (2 weeks/3 months). The dependent variables were the subscale scores on the Short-Form 36-item health survey (SF-36) and the Hospital Anxiety and Depression Scale (HADS).Results: At 2 weeks, significant differences were observed between groups on 5 of the 8 SF-36 subscale domain scores, with the white group reporting higher quality of life. Significant improvement in reported quality of life occurred in both groups over time on all domains of the SF-36, except bodily pain. There was a significantly greater improvement in favour of the white group for the role-physical domain. There was no significant difference between groups in terms of anxiety or depression at 2 weeks. Both groups showed a significant reduction in anxiety and depression by 3 months, but the degree of reduction was not significantly different between them. At 3 months, there was no significant difference between groups in terms of anxiety scores, but the South Asian group scored significantly higher on the depression scale.Conclusions: South Asian people have significantly poorer quality of life than white people after MI. While both groups showed improvement over time, South Asian people reported significantly less improvement in physical role function and were more depressed at 3 months. Identifying the factors accounting for such differences is important to develop models of care for delivering the most effective and culturally-sensitive interventions to this group

Minke whales change their swimming behavior with respect to their calling behavior, nearby conspecifics, and the environment in the central North Pacific

This research was supported by the Office of Naval Research (Code 322, Award Number N0001422WX01263), Commander, U.S. Pacific Fleet (Code N465JR, Award Number N0007023WR0EP8F), and tool development necessary for this analysis was supported by the U.S. Navy’s Living Marine Resources Program (Award Number N0002520WR0141R). AcknowledgmentsBehavioral responses to sonar have been observed in a number of baleen whales, including minke whales (Balaenoptera acutorostrata). Previous studies used acoustic minke whale boing detections to localize and track individual whales on the U.S. Pacific Missile Range Facility (PMRF) in Kaua ‘i, Hawai‘i before, during, and after Navy training activities. These analyses showed significant changes in central North Pacific minke whale distribution and swimming behavior during Navy sonar events. For the purposes of contextualizing changes in animal movement relative to Navy sonar, we expanded on this research to examine the natural variation in minke whale movement when Navy sonar was not present. This study included 2,245 acoustically derived minke whale tracks spanning the years 2012–2017 over all months that minke whales were detected (October–May). Minke whale movement was examined relative to calling season, day of the year, hour of day, wind speed, calling state (nominal or rapid), and distance to the nearest calling conspecific. Hidden Markov models were used to identify two kinematic states (slower, less directional movement and faster, more directional movement). The findings indicate that minke whales were more likely to travel in a faster and more directional state when they were calling rapidly, when other vocalizing minke whales were nearby, during certain times of the day and calling seasons, and in windier conditions, but these changes in movement were less intense than the changes observed during exposure to Navy sonar, when swim speeds were the fastest. These results start to put behavioral responses to Navy sonar into an environmental context to understand the severity of responses relative to natural changes in behavior.Publisher PDFPeer reviewe

Electrospinning of ultra-thin polymer fibers

The electrospinning technique was used to spin ultra-thin fibers from several polymer/solvent systems. The diameter of the electrospun fibers ranged from 16 nm to 2 μm. The morphology of these fibers was investigated with an atomic force microscope (AFM) and an optical microscope. Polyethylene oxide) (PEO) dissolved in water or chloroform was studied in greater detail. PEO fibers spun from aqueous solution show a “beads on a string” morphology. An AFM study showed that the surface of these fibers is highly ordered. The “beads on a string” morphology can be avoided if PEO is spun from solution in chloroform; the resulting fibers show a lamellar morphology. Polyvinylalcohol (PVA) dissolved in water and cellulose acetate dissolved in acetone were additional polymer/solvent systems which were investigated. Furthermore, the electrospinning process was studied: different experimental lay-outs were tested, electrostatic fields were simulated, and voltage - current characteristics of the electrospinning process were recorded

Molecular beam epitaxy of free-standing wurtzite AlxGa1xN layers

Recent developments with group III nitrides present AlxGa1xN based LEDs as realistic devices for new alternative deep ultra-violet light sources. Because there is a significant difference in the lattice parameters of GaN and AlN, AlxGa1xN substrates would be preferable to either GaN or AlN for ultraviolet device applications. We have studied the growth of free-standing wurtzite AlxGa1xN bulk crystals by plasma-assisted molecular beam epitaxy (PA-MBE). Thick wurtzite AlxGa1xN films were grown by PA-MBE on 2-in. GaAs (111)B substrates and were removed from the GaAs substrate after growth to provide free standing AlxGa1xN samples. X-ray microanalysis measurements confirm that the AlN fraction is uniform across the wafer and mass spectroscopy measurements show that the composition is also uniform in depth. We have demonstrated that free-standing wurtzite AlxGa1xN wafers can be achieved by PA-MBE for a wide range of AlN fractions. In order to develop a commercially viable process for the growth of wurtzite AlxGa1xN substrates, we have used a novel Riber plasma source and have demonstrated growth rates of GaN up to 1.8 mm/h on 2-in. diameter GaAs and sapphire wafer

Binding affinities and activation of Asp712Ala and Cys100Ser mutated kinin B1 receptor forms suggest a bimodal scheme for the molecule of bound-DABK

AbstractMutant forms of kinin B1 receptor (B1R) and analogs of the full agonist des-Arg9-bradykinin (DABK) were investigated aiming to verify the importance of selected receptor residues and of each agonist-peptide residue in the specific binding and activation. Linked by a specific disulfide bond (Cys100–Cys650), the N-terminal (Nt) and the EC3 loop C-terminal (Ct) segments of angiotensin II (AngII) receptor 1 (AT1R) have been identified to form an extracellular site for binding the agonist Nt segment (Asp1 and Arg2 residues). Asp712 residue at the receptor EC3 loop binds the peptide Arg2 residue. By homology, a similar site might be considered for DABK binding to B1R since this receptor contains the same structural elements for composing the site in AT1R, namely the disulfide bond and the EC3 loop Asp712 residue. DABK, Alan-DABK analogs (n=Ala1-, Ala2-, Ala3-, Ala4-, Ala5-, Ala6-, Ala7-, Ala8-DABK), and other analogs were selected to binding wild-type, Asp712Ala and Cys100Ser mutated B1R receptors. The results obtained suggested that the same bimodal scheme adopted for AngII-AT1R system may be applied to DABK binding to B1R. The most crucial similarity in the two cases is that the Nt segments of peptides equally bind to the homologous Asp712 residue of both AT1R and B1R extracellular sites. Confirming this preliminary supposition, mutation of residues located at the B1R extracellular site as EC3 loop Asp712 and Cys100 caused the same modifications in biological assays observed in AT1R submitted to homologous mutations, such as significant weakening of agonist binding and reduction of post-receptor-activation processes. These findings provided enough support for defining a site that determines the specific binding of DABK to B1R receptors