bluuebunny/crossref_metadata_2025 huggingface dataset:
Testing the impact of community composition on the productivity of a cool temperate eucalypt forest: the Australian Forest Evenness Experiment (AFEX)
Authors: Gerwin Melissa R. , Brinkhoff Rose , Britton Travis , Porter Meagan , Mallett Ruth K. , Hovenden Mark J.
Published: August 2020

Understanding the factors controlling productivity is crucial for modelling current and predicting future forest growth and carbon sequestration potential. Although abiotic conditions exert a strong influence on productivity, it is becoming increasingly evident that plant community composition can dramatically influence ecosystem processes. However, much of our understanding of these processes in forests comes from correlative studies or field experiments in short-statured, short-lived vegetation. Here, we present the background, design and implementation success of the Australian Forest Evenness Experiment (AFEX), which was designed to investigate the influence of community composition on the processes that contribute to forest productivity. Eighty 25 × 25-m plots, covering 5 ha in a logged, burnt forest coupe in south-eastern Tasmania were sown with four tree species, namely Eucalyptus delegatensis R.T.Baker, E. regnans F.Muell., Acacia dealbata Link and Pomaderris apetala Labill., in varying combinations to provide a range of evenness levels with each of the four species as target dominant. Despite some differences between sown composition and realised composition 1year after sowing, a substantial range of community evenness and local neighbourhood densities and compositions existed in the experiment. Thus, this site provides a unique opportunity to determine the influence of local neighbourhood composition on a range of ecological processes.
Approaching text genre
Authors: Milin Petar , Nenadić Filip , Ramscar Michael
Published: August 2020

In the present study, we sought to clarify how differences in contextualized experience influence the performance of
participants engaged in genre decision-making. Using a simple learning algorithm, we ran a series of computational simulations to model the
effects that context and cue competition have on the way readers of different backgrounds make genre decisions. Next, we used the results of
those simulations as predictions for our behavioural genre decision experiment. Differences in test performance were strongly influenced by
the factors that have long been known to influence learning: Cue competition and its embedding in a specific context jointly modulate what
gets learned and that inevitably affects later performance. We discuss our findings in the context of learning and literary genres.
Science fiction prototyping’s features and impact on college students’ perceptions of writing
Authors: Nicholes Justin
Published: August 2020

The present study develops an applied literariness study by exploring both the features, and the impact, of science fiction prototyping (SFP) on college students’ perceptions of disciplinary, or field-specific, writing. College students (N = 83), who were English (n = 35) or STEM (science, technology, engineering, mathematics) majors (n = 48), composed micro-science fiction prototyping (µSFP), a genre that blends creative and science writing. Linguistic Inquiry and Word Count (LIWC2015) analysis demonstrated that, aside from a more positive average emotional tone,µSFP written fell psycho-linguistically between personal and science writing. English and STEM majors’µSFP stories were similar in terms of analytical levels, clout, authenticity, emotional tone, and use of words. Mann-Whitney U tests indicated that, while English majors evaluated creative writing as significantly more relevant to their future career goals pre-intervention than did STEM majors (p = .04,r = .23), this difference vanished post-intervention. Additionally, while STEM majors evaluated science writing as significantly more worth their time to study (p = .042,r = .22) and relevant to their major (p = .01,r = .28) pre-intervention than did English majors, these differences disappeared post-intervention. Wilcoxon signed-ranks tests indicated that, while English majors’ ownership and evaluation of science and creative writing did not change, STEM majors’ evaluations of creative writing as relevant to their majors and future careers were significantly higher post-intervention (p = .015,r = .35)
Geographic Differences in Receipt of Addictions Treatment in a National Sample of Patients with Alcohol use Disorders from the U.S. Veterans Health Administration
Authors: Edmonds Amy T. , Bensley Kara M. , Hawkins Eric J. , Williams Emily C.
Published: August 2020

Background

In the United States, alcohol use disorder (AUD) is common and costly but substantially undertreated. Rurality is an important determinant of health that may influence receipt of evidence-based alcohol-related care. In a large, national sample of Veterans Health Administration (VA) patients with AUD with documented and non-Hispanic Black, Hispanic, or non-Hispanic White race/ethnicity, we examine whether meeting national Healthcare Effectiveness Data and Information Set (HEDIS) quality measures for specialty addictions care and receiving evidence-based medications for AUD differs across patients living in urban, large rural, and small rural areas.

Methods

VA electronic health record data were used to identify all patients with AUD documented in Fiscal Year 2012. Rurality was measured using a three-category rural and urban commuting area (RUCA) classification linked to patient zip code. Logistic regression models with clustered standard errors—iteratively adjusted for hypothesized confounders—were used to estimate the likelihood and marginal probabilities of receiving care for patients living in small and large rural areas, relative to urban areas. Primary outcomes included HEDIS initiation (any visit within 14 days of initial AUD visit after a 60-day period of no treatment), HEDIS engagement (2 or more AUD visits within 30 days of HEDIS initiation visit) and having any filled prescription for AUD medications (naltrexone, disulfiram, acamprosate, or topiramate).

Results

For all outcomes, patients living in large and small rural areas had a lower likelihood of receiving evidence-based AUD treatment than patients living in urban areas (all p-values < 0.05); differences in marginal probabilities across groups were relatively small.

Conclusions

In this national sample of VA patients with AUD, those living in more rural areas were less likely to receive evidence-based treatment for AUD than those living in urban areas. Further research is needed to investigate strategies to increase receipt of specialty care and pharmacotherapy in more rural areas.
Methodological analysis for the electrooptic coefficient and birefringence of BaTiO3 crystal films with complementary polarization modulations
Authors: Sun Na , Sun DeGui , Han Yue , Luo Mengxi , Chen Zhuo , Chen Chen
Published: August 2020

BaTiO3 crystal films, possessing advanced electrooptic (EO) properties, have spurred a broad interest in research and development of EO modulators for fiber-optic communications. However, the EO coefficient is still at uncontrollable and unoriented states despite it playing a crucial role in developing applicable industrial devices. In this work, accurate measurements of the EO coefficient

r

51

and birefringence

b

e
o

of BaTiO3 crystal films are implemented with a theorem-based theoretical model, an embedded waveguide/electrode device configuration and a complementary modulation of both the linear and ellipse polarizations. Then, with two state-of-the-art device samples on different crystal films, the final average values of the

r

51

and

b

e
o

are 410 ± 8 pm V−1 and −0.0208 ± 0.0003 for Sample-1 and 624 ± 31 pm V−1 and −0.0138 ± 0.0015 for Sample-2, respectively. Furthermore, a theoretical model for analyzing the measurement accuracies of

r

51

and

b

e
o

is proposed and the accuracy dependences on the two key variables, drive voltage and optic–electric interaction efficiency, are investigated. Finally, the limitations to the measurement accuracy of this methodology are discussed, including the effect of temperature on the measurement accuracy of

r

51

.
High-precision location for occluded reference hole based on robust extraction algorithm
Authors: Lou Huacheng , Lu Min , Cui Haihua , Jiang Tao , Tian Wei , Huang Yi
Published: August 2020

The reference hole is significant for pre-positioning in high-precision robot drilling. The visual and optical measurement of such holes is of great benefit in terms of improving location accuracy during robot drilling and subsequent rivet-in-hole assembly. However, the detection and location of the reference hole via visual sensors still presents signifcant challenges, owing to the occlusion of perforator clips prior to practical drilling. This study proposes a robust extraction algorithm, based on gray clustering and edge detection, for locating the occluded reference holes (ORH). Firstly, the boundary box of the ORH is segmented using a template matching and density clustering algorithm. Secondly, the discrete arcs of the ORH are extracted via a combination of K-means clustering, pixel-intensity, and concave points extraction based on edge concavity. Finally, the target arcs are filtered and obtained based on their ellipse geometric properties, followed by the center extraction of the ellipse fitting. The experimental results show that the location accuracy achieved in this way is within 0.03 mm, which is sufficiently accurate for robot drilling. Moreover, the ORH data can be extracted and located successfully even in challenging industrial environments, with varying levels of illumination.
Impact of carbon nanotube pattern layers on gallium nitride-based light emitting diodes
Authors: Tian M F , Feng X J , Long H , Ying L Y , Zhang B P , Wang K , Yu T J
Published: August 2020

Patterned sapphire substrate has been used extensively in the growth of gallium nitride (GaN) material and related light emitting devices (LEDs). Recently, carbon nanotube patterned sapphire (CNTPS) was utilized to improve the GaN material and LED devices. In this article, intrinsic analyzation of LEDs on CNTPS were studied. LEDs grown on three layers of CNTs showed highest radiative quantum efficiency and internal quantum efficiency, while LEDs on double layers of CNTs exhibited the best light output power and external quantum efficiency. The physics of carriers’ injection, radiative, non-radiative, Auger recombination and light extraction in CNT patterned LEDs were unraveled by the ‘ABC’ modelsimulation.
Radio frequency interference mitigation using pseudoinverse learning autoencoders
Authors: Wang Hong-Feng , Yuan Mao , Yin Qian , Guo Ping , Zhu Wei-Wei , Li Di , Feng Si-Bo
Published: August 2020

Radio frequency interference (RFI) is an important challenge in radio astronomy. RFI comes from various sources and increasingly impacts astronomical observation as telescopes become more sensitive. In this study, we propose a fast and effective method for removing RFI in pulsar data. We use pseudo-inverse learning to train a single hidden layer auto-encoder (AE). We demonstrate that the AE can quickly learn the RFI signatures and then remove them from fast-sampled spectra, leaving real pulsar signals. This method has the advantage over traditional threshold-based filter method in that it does not completely remove contaminated channels, which could also contain useful astronomical information.
Study of the Modified Gaussian Model on olivine diagnostic spectral features and its applications in space weathering experiments
Authors: Han Hui-Jie , Lu Xiao-Ping , Yang Ya-Zhou , Zhang Hao , Mutelo Admire Muchimamui
Published: August 2020

The absorption features of olivine in visible and near-infrared (VNIR) reflectance spectra are the key spectral parameters in its mineralogical studies. Generally, these spectral parameters can be obtained by exploiting the Modified Gaussian Model (MGM) with a proper continuum removal. However, different continua may change the deconvolution results of these parameters. This paper investigates the diagnostic spectral features of olivine with diverse chemical compositions. Four different continuum removal methods with MGM for getting the deconvolution results are presented and the regression equations for predicting the Mg-number (Fo#) are introduced. The results show that different continua superimposed on the mineral absorption features will make the absorption center shift, as well as the obvious alterations in shape, width and strength of the absorption band. Additionally, it is also found that the logarithm of a second-order polynomial continuum can match the overall shape of the spectrum in logarithmic space, and the improved regression equations applied to estimate the chemical composition of olivine-dominated spectra also have a better performance. As an application example, the improved approach is applied to pulse laser irradiated olivine grains to simulate and study the space weathering effects on olivine diagnostic spectral features. The experiments confirm that space weathering can make the absorption band center shift toward longer wavelength. Therefore, the Fo# estimated from remote sensing spectra may be less than its actual chemical composition. These results may provide valuable information for revealing the difference between the spectra of olivine grains and olivine-dominated asteroids.
Extended Mittag-Leffler function, series and its sum
Authors: Jaraldpushparaj S , Britto Antony Xavier G
Published: August 2020

This paper introduces first order extended Mittag-Leffler function by using generalized polynomial factorials. By applying generalized ℓ–difference operator, we obtain a formula for the series having extended Mittag-Leffler functions which has several applications in fractional calculus. Suitable examples and numerical verification by MATLAB are inserted to validate our findings.
Stability and neimark - sacker bifurcation for a discrete system of one - scroll chaotic attractor with fractional order
Authors: George Maria Selvam A , Dhineshbabu R , Gumus Ozlem AK
Published: August 2020

This present work investigates the dynamical behaviors of a new form of fractional order three dimensional system with a chaotic attractor of the one-scroll structure and its discretized counterpart. Firstly, existence and parametric conditions for local stability analysis of steady states of the model are addressed. Then the bifurcation theory is applied to investigate the presence of Neimark - Sacker (NS) bifurcations at the coexistence steady state taking the time delay as a bifurcation parameter in the discrete fractional order system. Also the trajectories, phase diagrams, limit cycles, bifurcation diagrams, attractors for period - 1, 2, 3, 4, 5 and a chaotic attractor with one scroll are exhibited for biologically meaningful sets of parameter values in the discretized system. Finally, several numerical examples are presented to assure the validity of the theoretical results and further rich dynamics of the model is explored as well.
Visco thermo elastic waves in a nonhomogeneous piezoelectric resonator plate of polygonal shape
Authors: Infant Sujitha G , Selvamani R
Published: August 2020

In this paper the propagation of non-homogeneous waves in visco thermo elastic piezoelectric plate is studied with the application of linear elasticity theory. The considered plate is resonator in nature. The stress strain equations are formulated using non homogeneous form of three dimensional linear elasticity theory. The solution of the problem is derived using the Bessel function of first and second kind. The irregular boundary conditions are evaluated using the Fourier expansion collocation method. The numerical computations are carried out for triangle, square, pentagon and hexagon shapes of resonator plates. The dispersion curves are presented for the physical variables.
On fuzzy upper and lower almost e*(resp. δSand (δp)-continuous multifunctions
Authors: Poonguzhali M. , Loganathan C. , Vijayalakshmi B. , Vadivel A.
Published: August 2020

In this paper, we introduce the concepts of fuzzy upper and fuzzy lower almoste*-continuous multifunctions on fuzzy topological spaces inŜostak’s sense. Several characterizations and properties of these fuzzy upper (resp. fuzzy lower) almoste* -continuous multifunctions are presented and their mutual relationships are established inL-fuzzy topological spaces. Later, composition and union between these multifunctions have been studied.
Ulam stability of solutions of a discrete boundary value problem with fractional order
Authors: George Maria Selvam A , Dhineshbabu R
Published: August 2020

In this present work, we investigate Ulam - Hyers stability for the following nonlinear discrete fractional order boundary value problem of the form

0
C

Δ
k
δ

υ
(
k
)
=
ψ
(
k
+
δ
−
1
,
υ
(
k
+
δ
−
1
)
)
,

for

k
∈

[
0
,
L
]

N
0

=
{
0
,
1
,
…
,
L
}

, with boundary conditions

υ
(
δ
−
2
)
=
0
=
υ
(
δ
+
L
)

, where

ψ
:

[
δ
−
1
,
δ
+
L
]

N
δ
−
1

×
R
→
R

is a continuous and

0
C

Δ
k
δ

is the Caputo fractional difference operator with 1 < δ ≤ 2.
Natural convection in an inclined parallelogrammic enclosure: Effect non-uniform heating
Authors: Ravindra P , Pandurangappa C , Sankar M
Published: August 2020

In this paper, numerical simulations are presented to understand the influence of inclination angle of a tilted parallelogrammic enclosure. The upper and lower boundaries of the enclosure are treated as thermally insulated; right wall is uniform cooled while the left wall is non-uniformly heated with either sinusoidal or linear thermal profiles. Using Darcy law, the momentum equations are modeled and unsteady energy equation is considered. The model equations are numerically solved using finite difference method, in particular, using ADI and SLOR methods. Based on standard coordinate transformations, the governing equations are transformed to rectangular shaped enclosure computational domain. In this analysis, due to large number parameters, the inclination angle of the enclosure is fixed. The flow and thermal processes are depicted through streamlines and isotherms, while the thermal transport rates are illustrated through Nusselt number profiles. Numerical simulations capture the effects of side wall inclination angle and non-uniform thermal conditions on the flow and thermal patterns, heat transport rates for various parametric ranges of the problem.
Value distribution theory of Nevanlinna
Authors: Rajeshwari S
Published: August 2020

In the field of research, a century old value distribution theory of Nevanlinna is still alive. It contains a broad range of implementations inside and outside a function theory. It is the study to speculate different values by complex function. As you are aware that each single non-constant variable polynomial upon ℂ has has not more than one root which is complex. This builds polynomials with real coefficients, because upon seeing the real number as a complex number with its imaginary part equal to zero up to constant multiple. This article express mainly the classical version for complex analytic map to the Riemann sphere of single variable, with priority on mero-morphic functions in the z-plane.
The least monopoly energy of fuzzy graph
Authors: Rajeshwari M , Murugesan R , Venkatesh K A
Published: August 2020

In this paper, we present least monopoly energy of fuzzy graph and also computed lower and upper bound. Some examples have been illustrated.
On feasibility of azimuthal flow studies with Principal Component Analysis
Authors: Altsybeev Igor
Published: August 2020

It is shown that the Principal Component Analysis applied to azimuthal single-particle distributions allows to perform flow analysis in ways that are analogous to the traditional approaches based on multi-particle correlations. In particular, symmetric cumulants are considered. It is demonstrated also that statistical fluctuations due to a finite number of particles per event practically do not play a role for higher order PCA-based cumulants.
Heavy flavor dynamics across system size at the LHC
Authors: Katz Roland , Prado Caio A. G. , Noronha-Hostler Jacquelyn , Suaide Alexandre A. P.
Published: August 2020

One of the fundamental signatures of the Quark Gluon Plasma has been the suppression of heavy flavor (specifically D mesons), which has been measured via the nuclear modification factor, RAA
and azimuthal anisotropies, vn
, in large systems. However, multiple competing models can reproduce the same data for RAA
to vn
. In this talk we break down the competing effects that conspire together to successfully reproduce RAA
and vn
in experimental data using Trento+v-USPhydro+DAB-MOD. Then using our best fit model we make predictions for RAA
and vn
across system size for 208PbPb, 129XeXe, 40ArAr, and 16OO collisions. We find that 0–10% centrality has a non-trivial interplay between the system size and eccentricities such that system size effects are masked in v2 whereas in 30–50% centrality the eccentricities are approximately constant across system size and, therefore, is a better centrality class to study D meson dynamics across system size.
PHENIX results on

J/ψ

polarization in p+p collisions.
Authors: Lebedev Alexandre
Published: August 2020

One of the big questions in quarkonia production is how heavy-quark pairs are produced in the initial hard scattering and hadronize into final quarkonia states. This question also affects the estimation of quarkonia breakup cross-sections and color screening in heavy ion collisions. Many existing models describe well general features of quarkonia production like cross-section and transverse momentum distributions. In order to differentiate between various models one has to study quarkonia production in more details. One of such tools is a study of angular distributions of decay leptons, usually called polarization. The PHENIX experiment has measured inclusive

J
/
ψ

polar and azimuthal angular decay coefficients in the mid

(

|
y
|
<
0.35

)

and forward

(

1.2
<
|
y
|
<
2.2

)

rapidity regions in p+p collisions at 200 GeV and 510 GeV. This talk will present the analysis strategy as well as the results in different polarization frames.
How to Avoid Total Dissolved Gas Supersaturation in Water from Hydropower Plants by Employing Ultrasound
Authors: Rognerud Maren Elise , Solemslie Bjørn W. , Islam H. , Pollet Bruno G.
Published: August 2020

In Norway, more than 10 hydropower plants are known to have caused biologically relevant levels of total dissolved gas supersaturation in the rivers downstream power plants. This phenomenon is causing fish kills due to gas bubble disease and have large impacts on the biodiversity. The gas supersaturation is often caused by undersized or blocked brook intakes creating turbulent flows and resulting in large amounts of air dragged into the tunnel. One possible solution to this problem is employing power ultrasound (20 kHz - 1 MHz) for degassing water prior to releasing it back into the river system. Acoustic cavitation is known to have a positive effect on the degassing mechanism, and this paper is investigating whether ultrasound can be applied to create acoustic cavitation and avoid biologically relevant levels of total dissolved gas supersaturation from hydropower plants. The objective is to develop background knowledge for constructing an experimental setup in the Waterpower Laboratory at NTNU to investigate whether gas supersaturation can be decreased from power plants by application of ultrasound. Preliminary experiments, carried out at the NTNU Hydrogen Energy and Sonochemistry Laboratory, exploring the behaviour of the degassing process at different ultrasonic frequencies and amplitudes conclude that the most effective degassing occur at high acoustic amplitude and a frequency of 24 kHz.
Effect of welding pattern during repair and maintenance of Francis runner on sediment erosion: An experimental investigation using RDA
Authors: Sharma Devendra , Khadka Bikalpa , Parajuli Aashutosh , Dahal Dadi Ram , Thapa Bhola
Published: August 2020

In Nepal, sediment erosion is a major cause of hydro-turbine failure. Every year turbine parts expose to water got eroded and failed ultimately resulting in loss of efficiency as well as increase in the repair cost. For repair of these eroded surfaces welding is quit famous in Nepal due to low cost to build up the eroded surface however specific welding pattern on the eroded surfaces has not been used which results low strength in repaired equipment. In this paper, the study of the relation of the welding pattern on the erosion rate had carried out taking the Francis turbine blade of Dhamile Khola (14 kW) as reference. Experimental analysis was adopted for studying the effect of welding pattern on erosion rate through laboratory tests. Four different welding patterns on four different specimens were developed and accelerated tests were carried out in the Rotating Disc Apparatus (RDA) at Turbine Testing Lab (TTL), Kathmandu University. Furthermore, erosion pattern on forged blades were compared with the CFD analysis carried out on same blade which is similar. After an operation time of 1050 minutes, the extent of wear was found significantly less in the test specimen with right inclined welding pattern taking material loss as a basis for comparison. The aim of this paper is to provide a specific welding pattern with relatively less erosion rate during the repair and maintenance of the sediment eroded surface of the runners.
Numerical investigation on the effects of leakage flow from Guide vane-clearance gaps in low specific speed Francis turbines
Authors: Gautam Saroj , Lama Ram , Chitrakar Sailesh , Neopane Hari Prasad , Thapa Biraj Singh , Zhu Baoshan
Published: August 2020

Clearance gap in guide vanes of Francis turbine induces the leakage vortex. This vortex flow interacts with the main flow and leads to the instability in the fluid flow pattern and eventually deteriorates the performance of the turbine. In this study, the detailed numerical examination of the unsteady flow due to leakage vortex and influence of this in the performance of turbine is carried out using time dependent numerical analysis. The numerical simulation is carried out using SST turbulence model with numerical validation. The development of leakage vortex is studied within the clearance gap region. Time dependent numerical simulation is carried out to investigate the growth and vortex propagation considering five revolutions of the runner. Results shows that the leakage vortex travelling form the guide vane clearance gaps influence the performance of the runner. On analysing the leakage vortex path, it is seen that the vortex travels from the pressure side of runner blade to the suction side of adjacent blade opposite to the runner rotation. Furthermore, this leakage vortex is carried down to the draft tube where the vortex rope seems to grow up to 50% geometric progression of draft tube cone and gradually decreases before reaching the elbow. Upon investigation of resulting torque and head during runner rotation, the periodic variation of torque and head can be seen, however with different phase. This is inferred to be the influence of leakage vortex that travels along with the main flow.
Parametric Hamilton’s equations for stochastic systems
Authors: Grigorio L S
Published: August 2020

In the context of instanton method for stochastic system this paper purposes a modification of the arclength parametrization of the Hamilton’s equations allowing for an arbitrary instanton speed. The main results of the paper are: (i) it generalizes the parametrized Hamilton’s equations to any speed required. (ii) Corrects the parametric action on the occasion that the Hamiltonian is small but finite and how it adjusts to the probability density function (pdf). (iii) Improves instanton approximation to pdf by noise and propagator renormalization. As an application of the above set up we evaluate the instanton and predict the statistics of two models: Ornstein–Uhlenbeck and passive scalar gradients in a Lagrangian model for turbulence, namely the scalar gradient recent fluid deformation closure.
Modeling proton-exchange-membrane fuel cell performance/degradation tradeoffs with chemical scavengers
Authors: Ehlinger Victoria M , Crothers Andrew R , Kusoglu Ahmet , Weber Adam Z
Published: August 2020

One of the primary limiting factors for proton-exchange-membrane (PEM) fuel-cell lifetime is membrane degradation driven by operational stressors such as generation of highly reactive radical species, which result in cell failure and voltage decay. To extend the lifetime of the membrane, cerium ions are added to the membrane to mitigate the effects of chemical degradation by scavenging radicals produced by crossover of reactant gases across the PEM. Although cerium has shown to be very effective at reducing chemical degradation during PEM fuel cell operation, the cerium ions also lead to a decrease in performance due to changes in the membrane transport properties and possible site blockage in the catalyst layers. In this paper, a full-cell, transient performance and durability model is presented in which a micro-kinetic framework accounts for gas crossover induced degradation and concentrated-solution theory describes transport in the PEM. The transport model takes into account the coupled nature of the electrochemical driving forces that cause transport of cerium ions, protons, and water. The cell model predicts the migration of cerium out of the membrane and into the catalyst layers and its impact on performance. A comparison between dilute-solution-theory and concentrated-solution-theory models shows how water management in the cell also effects cerium distribution, where higher relative humidity leads to better retention of cerium in the membrane. A voltage loss breakdown shows that cerium leads to performance losses in the cell both by decreasing proton activity and by modifying transport properties of water and protons through the membrane. Transient simulations show that the optimal tradeoff between performance and durability metrics is reached at low cerium concentrations in the membrane (less than 1% of membrane sulfonic acid sites occupied by cerium for our analysis). Finally, analysis of membrane thickness and catalyst layer thickness as design parameters shows that thicker membranes and thinner catalyst layers best optimize both performance and durability.
A qualitative evaluation of the effect of a longitudinal dementia education programme on healthcare student knowledge and attitudes
Authors: Daley Stephanie , Feeney Yvonne , Grosvenor Wendy , Hebditch Molly , Morley Leila , Sleater Gillian , Wright Juliet , Banerjee Sube
Published: August 2020

Background and objectives

There is a need to ensure that the future healthcare workforce has the necessary knowledge and skills to deliver high quality compassionate care to the increasing number of people with dementia. Our programme has been set up to address this challenge. In the programme, undergraduate healthcare students (nursing, medical and paramedic) visit a family (person with dementia and their carer) in pairs over a 2-year period. This qualitative study sought to understand the student experience of the programme.

Methods

Participants were undergraduate healthcare students who were undertaking our programme at two universities. We sampled for variation in the student participants in order to generate a framework for understanding the student experience of the programme. Students were invited to take part in the qualitative study, and written consent was obtained. Interviews and focus group transcripts were analysed using thematic analysis.

Results

Thirty-nine (nursing, medical and paramedic) student participants took part in individual in-depth qualitative interviews and 38 took part in five focus groups. Four key themes were identified from the analysis; relational learning, insight and understanding, challenging attitudes and enhanced dementia practice.

Discussion

Student experience of our programme was shown to be positive. The relationship between the students and family was most impactful in supporting student learning, and the subsequent improvement in knowledge, attitudes and practice. Our model of undergraduate dementia education has applicability for other long-term conditions.
The role of body mass index at diagnosis of colorectal cancer on Black–White disparities in survival: a density regression mediation approach
Authors: Devick Katrina L , Valeri Linda , Chen Jarvis , Jara Alejandro , Bind Marie-Abèle , Coull Brent A
Published: August 2020

The study of racial/ethnic inequalities in health is important to reduce the uneven burden of disease. In the case of colorectal cancer (CRC), disparities in survival among non-Hispanic Whites and Blacks are well documented, and mechanisms leading to these disparities need to be studied formally. It has also been established that body mass index (BMI) is a risk factor for developing CRC, and recent literature shows BMI at diagnosis of CRC is associated with survival. Since BMI varies by racial/ethnic group, a question that arises is whether differences in BMI are partially responsible for observed racial/ethnic disparities in survival for CRC patients. This article presents new methodology to quantify the impact of the hypothetical intervention that matches the BMI distribution in the Black population to a potentially complex distributional form observed in the White population on racial/ethnic disparities in survival. Our density mediation approach can be utilized to estimate natural direct and indirect effects in the general causal mediation setting under stronger assumptions. We perform a simulation study that shows our proposed Bayesian density regression approach performs as well as or better than current methodology allowing for a shift in the mean of the distribution only, and that standard practice of categorizing BMI leads to large biases when BMI is a mediator variable. When applied to motivating data from the Cancer Care Outcomes Research and Surveillance (CanCORS) Consortium, our approach suggests the proposed intervention is potentially beneficial for elderly and low-income Black patients, yet harmful for young or high-income Black populations.
Waves of Change: Brain Sensitivity to Differential, not Absolute, Stimulus Intensity is Conserved Across Humans and Rats
Authors: Somervail R , Zhang F , Novembre G , Bufacchi R J , Guo Y , Crepaldi M , Hu L , Iannetti G D
Published: August 2020

Living in rapidly changing environments has shaped the mammalian brain toward high sensitivity to abrupt and intense sensory events—often signaling threats or affordances requiring swift reactions. Unsurprisingly, such events elicit a widespread electrocortical response (the vertex potential, VP), likely related to the preparation of appropriate behavioral reactions. Although the VP magnitude is largely determined by stimulus intensity, the relative contribution of the differential and absolute components of intensity remains unknown. Here, we dissociated the effects of these two components. We systematically varied the size of abrupt intensity increases embedded within continuous stimulation at different absolute intensities, while recording brain activity in humans (with scalp electroencephalography) and rats (with epidural electrocorticography). We obtained three main results. 1) VP magnitude largely depends on differential, and not absolute, stimulus intensity. This result held true, 2) for both auditory and somatosensory stimuli, indicating that sensitivity to differential intensity is supramodal, and 3) in both humans and rats, suggesting that sensitivity to abrupt intensity differentials is phylogenetically well-conserved. Altogether, the current results show that these large electrocortical responses are most sensitive to the detection of sensory changes that more likely signal the sudden appearance of novel objects or events in the environment.
Ceftobiprole Compared With Vancomycin Plus Aztreonam in the Treatment of Acute Bacterial Skin and Skin Structure Infections: Results of a Phase 3, Randomized, Double-blind Trial (TARGET)
Authors: Overcash J Scott , Kim Charles , Keech Richard , Gumenchuk Illia , Ninov Borislav , Gonzalez-Rojas Yaneicy , Waters Michael , Simeonov Simeon , Engelhardt Marc , Saulay Mikael , Ionescu Daniel , Smart Jennifer I , Jones Mark E , Hamed Kamal A
Published: August 2020

Background

The development of novel broad-spectrum antibiotics, with efficacy against both gram-positive and gram-negative bacteria, has the potential to enhance treatment options for acute bacterial skin and skin structure infections (ABSSSIs). Ceftobiprole is an advanced-generation intravenous cephalosporin with broad in vitro activity against gram-positive (including methicillin-resistant Staphylococcus aureus) and gram-negative pathogens.

Methods

TARGET was a randomized, double-blind, active-controlled, parallel-group, multicenter, phase 3 noninferiority study that compared ceftobiprole with vancomycin plus aztreonam. The Food and Drug Administration-defined primary efficacy endpoint was early clinical response 48–72 hours after treatment initiation in the intent-to-treat (ITT) population and the European Medicines Agency-defined primary endpoint was investigator-assessed clinical success at the test-of-cure (TOC) visit. Noninferiority was defined as the lower limit of the 95% CI for the difference in success rates (ceftobiprole minus vancomycin/aztreonam) >−10%. Safety was assessed through adverse event and laboratory data collection.

Results

In total, 679 patients were randomized to ceftobiprole (n = 335) or vancomycin/aztreonam (n = 344). Early clinical success rates were 91.3% and 88.1% in the ceftobiprole and vancomycin/aztreonam groups, respectively, and noninferiority was demonstrated (adjusted difference: 3.3%; 95% CI: −1.2, 7.8). Investigator-assessed clinical success at the TOC visit was similar between the 2 groups, and noninferiority was demonstrated for both the ITT (90.1% vs 89.0%) and clinically evaluable (97.9% vs 95.2%) populations. Both treatment groups displayed similar microbiological success and safety profiles.

Conclusions

TARGET demonstrated that ceftobiprole is noninferior to vancomycin/aztreonam in the treatment of ABSSSIs, in terms of early clinical response and investigator-assessed clinical success at the TOC visit.

Clinical Trials Registration

NCT03137173.
Disrupting the riskscapes of inequities: a case study of planning for resilience in Canada’s Metro Vancouver region
Authors: Yumagulova Lilia
Published: August 2020

The analysis across spatial, temporal and governance scales shows an inequitable distribution of risk across Canada’s Metro Vancouver region. For First Nation communities in this region, this risk is rooted in the colonial history of land dispossession. This article makes a contribution by expanding our understanding of historic creation of riskscapes and a discussion of its implications as a multiscale governance issue that persists across space and time. This article also situates the impacts of projected sea level rise on Indigenous communities in the context of regional, provincial and federal settler-colonial flood risk management regime.
Urethral catheterization as an alternative method for collecting sperm in the black-footed ferret (Mustela nigripes)
Authors: Mackie Paula , Chan Biankha , Franke Maria , Mastromonaco Gabriela F
Published: August 2020

The endangered black-footed ferret (BFF; Mustela nigripes) is an important example of the benefits of assisted reproduction in species conservation with both semen evaluation and artificial insemination using fresh and frozen sperm being successfully incorporated into the breeding program. Currently, electroejaculation (EE) is routinely utilized for semen collection in BFFs, a technique that requires custom equipment and experienced operators, and does not consistently yield viable samples in this species. In this case study, we evaluated the feasibility of urethral catheterization (UC) for semen collection, a method predominately tested in domestic and non-domestic felids, on four occasions (three BFF males). After general anesthesia with a combination of ketamine, midazolam and α2-agonist dexmedetomidine (thought to promote semen release into the urethra), a lightly lubricated, flexible feeding tube was passed into the urethral opening and advanced ~7–8 cm into the urethra. A syringe attached to the feeding tube was used to apply mild negative pressure to collect sperm. Semen samples were successfully collected on all four attempts. Sperm characteristics ranged as follows: 10.5–26.0 × 106 sperm/ml concentration, 50–90% motility and 36–61% normal sperm morphology. This is the first report of the use of UC as a potential alternative to EE in the BFF, a more field-friendly technique that is less invasive and more consistent for obtaining samples free of urine contamination.
Trends in Corticosteroid Prescriptions for Ulcerative Colitis and Factors Associated with Long-Term Corticosteroid Use: Analysis Using Japanese Claims Data from 2006 to 2016
Authors: Matsuoka Katsuyoshi , Igarashi Ataru , Sato Noriko , Isono Yuri , Gouda Maki , Iwasaki Katsuhiko , Shoji Ayako , Hisamatsu Tadakazu
Published: August 2020

Background and Aims

Recent treatment guidelines for ulcerative colitis [UC] do not recommend long-term corticosteroid [CS] use. The present study aimed to capture the changes in CS use from 2006 to 2016 and to identify factors associated with long-term CS use after 2014, when the first two anti-tumour necrosis factor antibodies [infliximab and adalimumab] became available.

Methods

A retrospective study using the JMDC Claims Database included UC patients who initiated UC medications in any year from January 2006 to December 2016, or after January 2014, who were under continuous observation from 6 months before to 12 months after initiation. Patients with Crohn’s disease before initiation and those prescribed <8 days of CSs were excluded.

Results

Among 7907 UC patients who initiated UC medications within the study period, 1555 were prescribed CSs. The proportion of patients using CSs in each year decreased from 2011 as use of thiopurines and biologics increased. The proportion of patients with a starting dose ≥30 mg/day of CSs and patients continuing CSs for <90 days increased from 2011, reaching 49.1% and 41.0%, respectively, in 2016. However, even in 2016, 34.3% continued to use CSs for ≥180 days. Among 1230 patients with CS use after January 2014, low initial CS dose [<10 mg/day] was most strongly associated with long-term CS use [≥180 days].

Conclusions

CS use became more appropriate as use of thiopurine and biologics increased, although there were still many cases of inappropriate use. Long-term CS use was most strongly associated with low initial doses of CSs.
Community seroprevalence of COVID-19 in probable and possible cases at primary health care centres in Spain
Authors: Montenegro Patricia , Brotons Carlos , Serrano Jordi , Fernández Diana , Garcia-Ramos Carlos , Ichazo Begoña , Lemaire Jeannine , Moral Irene , Wienese Ricky Pérez , Pitarch Marc , Puig Mireia , Vilella M Teresa , Sellarès Jaume
Published: August 2020

Background

There is a scarcity of information about patients with mild or moderate symptoms during the coronavirus disease 2019 (COVID-19). This is especially true for those who attended and were followed up at primary care settings.

Objectives

We aim to measure the seroprevalence of antibodies against SARS-CoV-2 infection in a community sample of possible cases and among probable cases followed in primary care.

Methods

We selected a random sample of 600 individuals stratified by age groups from a total population of 19 899 individuals from a community area in Barcelona. We also invited all the patients that had been followed by General Practitioners (GPs). For both populations, we used COVID-19 rapid lateral flow immunoassays, which qualitatively assess the presence of patient-generated Immunoglobulins G (IgG) and Immunoglobulin M (IgM).

Results

Three hundred and eleven asymptomatic individuals from the randomly selected sample participated in the study. The mean age was 43.7 years [standard deviation (SD) = 21.79] and 55% were women. Seventeen individuals were seropositive for IgM and/or IgG, resulting in an overall prevalence of 5.47% (95% confidence interval = 3.44–8.58). Six hundred and thirty-four symptomatic patients were followed up by GPs. The mean age was 46.97 years (SD = 20.05) and 57.73% were women. Of these, 244 patients (38.49%) were seropositive. Results of the multivariate logistic regression analysis showed that the odds ratio for a positive test was significantly increased in patients who had fever, ageusia and contact with a patient diagnosed with COVID-19.

Conclusions

The seroprevalence of antibodies against SARS-CoV-2 among possible cases was lower than expected. Approximately, 40% of the symptomatic patients followed up by GPs during the peak months of the pandemic were positive.
A joint inversion of receiver function and Rayleigh wave phase velocity dispersion data to estimate crustal structure in West Antarctica
Authors: Dunham C K , O’Donnell J P , Stuart G W , Brisbourne A M , Rost S , Jordan T A , Nyblade A A , Wiens D A , Aster R C
Published: August 2020

We determine crustal shear wave velocity structure and crustal thickness at recently deployed seismic stations across West Antarctica, using a joint inversion of receiver functions and fundamental mode Rayleigh wave phase velocity dispersion. The stations are from both the UK Antarctic Network (UKANET) and Polar Earth Observing Network/Antarctic Network (POLENET/ANET). The former include, for the first time, four stations along the spine of the Antarctic Peninsula, three in the Ellsworth Land and five stations in the vicinity of the Pine Island Rift. Within the West Antarctic Rift System (WARS) we model a crustal thickness range of 18–28 km, and show that the thinnest crust (∼18 km) is in the vicinity of the Byrd Subglacial Basin and Bentley Subglacial Trench. In these regions we also find the highest ratio of fast (Vs = 4.0–4.3 km s–1, likely mafic) lower crust to felsic/intermediate upper crust. The thickest mafic lower crust we model is in Ellsworth Land, a critical area for constraining the eastern limits of the WARS. Although we find thinner crust in this region (∼30 km) than in the neighbouring Antarctic Peninsula and Haag-Ellsworth Whitmore block (HEW), the Ellsworth Land crust has not undergone as much extension as the central WARS. This suggests that the WARS does not link with the Weddell Sea Rift System through Ellsworth Land, and instead has progressed during its formation towards the Bellingshausen and Amundsen Sea Embayments. We also find that the thin WARS crust extends towards the Pine Island Rift, suggesting that the boundary between the WARS and the Thurston Island block lies in this region, ∼200 km north of its previously accepted position. The thickest crust (38–40 km) we model in this study is in the Ellsworth Mountain section of the HEW block. We find thinner crust (30–33 km) in the Whitmore Mountains and Haag Nunatak sectors of the HEW, consistent with the composite nature of the block. In the Antarctic Peninsula we find a crustal thickness range of 30–38 km and a likely dominantly felsic/intermediate crustal composition. By forward modelling high frequency receiver functions we also assess if any thick, low velocity subglacial sediment accumulations are present, and find a 0.1–0.8-km-thick layer at 10 stations within the WARS, Thurston Island and Ellsworth Land. We suggest that these units of subglacial sediment could provide a source region for the soft basal till layers found beneath numerous outlet glaciers, and may act to accelerate ice flow.
2. A Modern Litigation Approach
Authors: Macgregor Lucilla , Peacey Charlotte , Ridsdale Georgina
Published: August 2020

This chapter begins with a discussion of civil litigation reform. It focuses on the purpose of civil litigation. The application of the Civil Procedure Rules is detailed. Key features of civil practice in the courts, for example, the computation of time, are discussed. It considers the concept of the overriding objective and human rights and civil litigation.