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We investigate the endofullerene system Ne@C70 by constructing a three-dimensional Potential Energy Surface (PES) describing the translational motion of the Ne atom. This is constructed from electronic structure calculations from a plethora of methods, including MP2, SCS-MP2, SOS-MP2, RPA@PBE, and C(HF)-RPA, which were previously used for He@C60 in Panchagnula et al. [J. Chem. Phys. 160, 104303 (2024)], alongside B86bPBE-25X-XDM and B86bPBE-50X-XDM. The reduction in symmetry moving from C60 to C70 introduces a double well potential along the anisotropic direction, which forms a test of the sensitivity and effectiveness of the electronic structure methods. The nuclear Hamiltonian is diagonalized using a symmetrized double minimum basis set outlined in Panchagnula and Thom [J. Chem. Phys. 159, 164308 (2023)], with translational energies having error bars ±1 and ±2 cm−1. We find no consistency between electronic structure methods as they find a range of barrier heights and minima positions of the double well and different translational eigenspectra, which also differ from the Lennard-Jones (LJ) PES given in Mandziuk and Bačić [J. Chem. Phys. 101, 2126–2140 (1994)]. We find that generating effective LJ parameters for each electronic structure method cannot reproduce the full PES nor recreate the eigenstates, and this suggests that the LJ form of the PES, while simple, may not be best suited to describe these systems. Even though MP2 and RPA@PBE performed best for He@C60, due to the lack of concordance between all electronic structure methods, we require more experimental data in order to properly validate the choice. [ABSTRACT FROM AUTHOR]

Collisional analysis combines the effects of collisional relaxation and large-scale expansion to quantify how solar wind parameters evolve as the plasma expands through the heliosphere. Though previous studies have applied collisional analysis to the temperature ratio between protons (ionized hydrogen) and α-particles (fully ionized helium), this is the first study to explore α-proton differential flow with collisional analysis. First, the mathematical model for the collisional analysis of differential flow was derived. Then, this model was applied to individual in-situ observations from Parker Solar Probe (PSP; r =0.1-0.27 au) to generate predictions of the α-proton differential flow in the near-Earth solar wind. A comparison of these predicted values with contemporaneous measurements from the Wind spacecraft (r =1.0 au)shows strong agreement, which may imply that the effects of expansion and Coulomb collisions have a large role in governing the evolution of differential flow through the inner heliosphere. [ABSTRACT FROM AUTHOR]

Background: Standardized order sets are a means of increasing adherence to clinical practice guidelines and improving the quality of patient care. Implementation of novel quality improvement initiatives like order sets can be challenging. Before the COVID-19 pandemic, we conducted a formative evaluation to understand healthcare providers' perspectives on implementing clinical changes and the individual, collective and organizational contextual factors that might impact implementation at eight hospital sites in Alberta, Canada. Methods: We utilized concepts from the Consolidated Framework for Implementation Research (CFIR) and Normalisation Process Theory (NPT) to understand the context, past implementation experiences, and perceptions of the cirrhosis order set. Eight focus groups were held with healthcare professionals caring for patients with cirrhosis. Data were coded deductively using relevant constructs of NPT and CFIR. A total of 54 healthcare professionals, including physicians, nurses, nurse practitioners, social workers and pharmacists and a physiotherapist, participated in the focus groups. Results: Key findings revealed that participants recognized the value of the cirrhosis order set and its potential to improve the quality of care. Participants highlighted potential implementation challenges, including multiple competing quality improvement initiatives, feelings of burnout, lack of communication between healthcare provider groups, and a lack of dedicated resources to support implementation. Conclusions: Implementing a complex improvement initiative across clinician groups and acute care sites presents challenges. This work yielded insights into the significant influence of past implementation of similar interventions and highlighted the importance of communication between clinician groups and resources to support implementation. However, by using multiple theoretical lenses to illuminate what and how contextual and social processes will influence uptake, we can better anticipate challenges during the implementation process. [ABSTRACT FROM AUTHOR]

Owing to its low density and high temperature, the solar wind frequently exhibits strong departures from local thermodynamic equilibrium, which include distinct temperatures for its constituent ions. Prior studies have found that the ratio of the temperatures of the two most abundant ions—protons (ionized hydrogen) and α -particles (ionized helium)—is strongly correlated with the Coulomb collisional age. These previous studies, though, have been largely limited to using observations from single missions. In contrast, this present study utilizes contemporaneous, in situ observations from two different spacecraft at two different distances from the Sun: the Parker Solar Probe (PSP; r = 0.1–0.3 au) and Wind (r = 1.0 au). Collisional analysis, which incorporates the equations of collisional relaxation and large-scale expansion, was applied to each PSP datum to predict the state of the plasma farther from the Sun at r = 1.0 au. The distribution of these predicted α –proton relative temperatures agrees well with that of values observed by Wind. These results strongly suggest that, outside of the corona, relative ion temperatures are principally affected by Coulomb collisions and that the preferential heating of α -particles is largely limited to the corona. [ABSTRACT FROM AUTHOR]

Thermal motion of four liquid lead nanoinclusions attached to fixed dislocation segments joining in a dislocation node in aluminum-based alloy at 485°C is studied in-situ using TEM. The mutual interaction of the inclusions in all pairs is detected demonstrating the collective interaction of the all inclusions. The time-correlated thermal motion of each of the inclusions, and time-correlated thermal motion of the inclusions in all the pairs are indicated. Phase spectra of the time dependencies of the positions of the inclusions on the dislocations obtained using FFT reveal an existence of a common harmonic in their thermal oscillations at low frequencies demonstrating synchronous oscillations of the inclusions. The transition between synchronous and asynchronous dynamics of the thermal oscillations of the inclusions with increasing frequency is observed. The external vibrations introduced by the inclusion attached to the dislocation node are probably the reason for this transition. [ABSTRACT FROM AUTHOR]

Permutation tests based on previously developed statistics are proposed for the case of mixed paired and two-sample designs. Different weighting schemes of previous tests are explored to understand the strengths and weaknesses of each test. A simulation study compares the power and Type I error rates of the new tests with those previously developed. Rank-based statistics generally performed as well as or better than parametric statistics, particularly for nonnormal distributions. [ABSTRACT FROM AUTHOR]

The article revolves around the socio-political context of the year 1970 and its implications on racial issues in the U.S. It reflects on the challenges the country faced during that time, including racism, sexism, homophobia, and class wars. It emphasizes the role of black women in addressing these challenges and building a black feminist consciousness.

Electronic and geometrical structures of neutral, negatively, and positively charged (GaAs)n clusters are computed using density functional theory with generalized gradient approximation. All-electron computations are performed on (GaAs)2–(GaAs)9 while effective core potentials (ECPs) are used for (GaAs)9–(GaAs)15. Calibration calculations on GaAs and (GaAs)9 species support the use of the ECP for the larger clusters. The ground-state geometries of (GaAs)n- and/or (GaAs)n+ are different from the corresponding neutral ground-state geometry, except for n=7, 9, 12, 14, and 15, where the neutral and ions have similar structures. Beginning with n=6, all atoms are three coordinate, except for (GaAs)10+ and (GaAs)13+. For the larger species, there is a competition between fullerenes built from hexagons and rhombi and geometrical configurations where Ga–Ga and As–As bonds are formed, which results in the formation of pentagons. As expected, the static polarizability varies in the order of anion>neutral>cation, but the values are rather similar for all three charge states. The thermodynamic stability for the loss of GaAs is reported. [ABSTRACT FROM AUTHOR]

The purpose of this study was to explore the effects of arm movements on postural control when standing under different sensory conditions in healthy young and older adults. Fifteen young (mean ± SD age; 21.3 ± 4.2 years) and 15 older (mean ± SD age; 73.3 ± 5.0 years) adults completed the modified Romberg test, which uses four task manipulations (i.e. eyes open and eyes closed on a firm and foam surface) to compromise the fidelity of sensory feedback mechanisms. Each participant completed the tasks under two arm movement conditions: restricted and free arm movements. Centre of pressure (COP) range and frequency were calculated to characterise postural performance and strategy, respectively. Older adults showed greater COP range with restricted compared to free arm movements during all modified sensory conditions, with these effects most prominent in the medio-lateral (ML) plane (all p <.05, Cohen's d = 0.69–1.61). Compared to the free arm movement condition, there was an increase in ML displacement and frequency when arm movements were restricted during only the most challenging (i.e. vestibular dominant) task in young adults (all p <.05, d = 0.645–0.83). Finally, main age effects for the arm restriction cost (p <.05) indicates a greater reliance on an upper body strategy in older compared to young adults, independent of sensory availability/accuracy. These findings indicate that older adults compensate for the loss of accuracy in sensory input by increasing reliance on upper body movement strategies. • We explored how arm movements influence balance under different sensory conditions. • Arm movement restriction effects were more pronounced for challenging balance tasks. • Reliance on an upper body strategy was greater in older compared to young adults. [ABSTRACT FROM AUTHOR]

Large multiconfiguration Dirac–Fock calculations were performed for all neutral and up to 7 and 8 times ionized species of elements 107 and 108, respectively, as well as all the homologous elements Mn, Tc, Re, Fe, Ru, and Os for a number of different total angular momenta. Comparison of the resulting ionization potentials to the known values of the homologues allow an extrapolation and thus a prediction of the chemically important seven or eight ionization potentials of elements 107 or 108 as well as a prediction of some ionic radii. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Background. Interventions administered to critically ill patients, including mechanical ventilation, sedation or other treatments may hinder communication between patients and nurses. These communication challenges may affect critical care nurses' ability to provide compassionate, person-centred care. Objective. To identify nurses' experiences with patients who are communication-vulnerable in the intensive care unit and how they affect nurses' ability to offer compassionate care. Method. This qualitative explorative descriptive study involved nurses who worked in intensive care units from four private hospitals in Gauteng, South Africa. Focus groups were conducted with 30 critical care nurses in groups of two to six participants each. Thematic analysis was used to identify themes. Results. Five main themes were identified based on nurses' reports of their experiences with critically ill patients who experience communication difficulties and their impact on rendering compassionate care. Themes were deductively identified based on the social purposes of communication categories. Participants indicated that communication-vulnerable patients influence their ability to provide compassionate care. Generally, the physical, emotional, social and communication difficulties of assisting communication-vulnerable patients caused nurses to feel frustrated and negative towards their work environment, which added to their work stress and sometimes resulted in compassion fatigue. Conclusion. The study shows that various factors could impact the nurses' ability to provide compassionate care and that they require support to provide person-centred care. These factors can include the physical environment, the patient's alertness and awareness and institutional barriers. To support nurses in providing compassionate care, communication partner training may be warranted. [ABSTRACT FROM AUTHOR]

This essay performs a quare reading of the film Moonlight to demonstrate how the film illuminates an alternative path to sexual selfhood that is paradoxically facilitated not by access to material wealth or socioeconomic mobility, but rather through abject poverty. Through what the author refers to as a "makeshift masculinity," the use of Yoruba cosmology, and an analysis of sexuality, the essay traces the various stages of the protagonist Little/Chiron/Black's life and his relationship with his friend, Kevin, to highlight how a working-class epistemology might offer a different understanding of black same-sex desire. [ABSTRACT FROM AUTHOR]

The purification process of wastewater containing heavy metal ions (HMIs) using nano-fibrous metal-organic frameworks, MOF-808, embedded polyacrylonitrile membrane has been studied. The process parameters that were evaluated included feed concentration, transmembrane pressure (TMP), and membrane thickness. The effect of coexisting cations in the solution upon the removal efficiencies of Zn2+, Cd2+, Pb2+ and Hg2+ ions was also investigated. Results from the filtration experiments indicate a substantial variation in the feed volume that the membrane can treat before the permeate lead concentration reaches the allowable limit of 10 ppb, depending on the process parameter. An increase in the membrane thickness showed a significant improvement (26%) with 440 L of the treated feed volume after doubling the membrane layer. An increase in TMP could reduce the treated feed volume by 38% while a decrease in feed concentration led to a 21% increase in the treated feed volume. In the presence of other common background cations in the solution, the removal efficiency of HMIs by adsorption onto MOF-808 dropped by 18 to 37%. This result was dependent upon the HMIs, in the presence of up to three other cations but was minimal in the presence of a single cation indicative of good selectivity. Unlabelled Image • Metal-organic frameworks particles were enmeshed into polyacrylonitrile nanofiber membranes. • The membranes were used for the removal of Pb2+ ions from aqueous solution by adsorption. • The effects of transmembrane pressure, feed conc., and membrane thickness were investigated. • The presence of background ions on adsorption Zn2+, Cd2+, Pb2+ and Hg2+ ions was studied. • The filtration system could produce >500 L of pure water per m2 of membrane. [ABSTRACT FROM AUTHOR]

Arthrodesis of the interphalangeal (IP) joint of the thumb is widely acknowledged as the indicated treatment for trauma and osteoarthritis of this joint. Joint replacement was offered to a young patient as an alternative treatment after traumatic joint loss of the IP joint in her thumb. This allowed her to maintain motion of the joint as she did not wish to move forward with fusion. In the present case, a Humanitarian Use Device (HUD) was utilized in an off-label manner and placed into the interphalangeal joint of the patient's thumb. The patient did well postoperatively with reasonable pain-free range of motion of the interphalangeal joint with an arc of 40 degrees. We propose that joint replacement is a viable alternative to arthrodesis in select patients who do not wish to be fused. We believe this represents the first thumb IP joint replacement using a semiconstrained joint presented in the medical literature. [ABSTRACT FROM AUTHOR]

A polymerase chain reaction (PCR) assay for detecting avian leukosis/sarcoma viruses (ALSV) in chickens was developed, using primers we developed for specifically detecting subgroups A-E and J, ALSV infections. The performance of the assay was compared with that of published PCR methods, on DNA extracted from paraffinembedded tissues from chickens confirmed to be infected with ALSV subgroups A and J, by neutralization and ELISA tests. The results of some of our primer sets used in the assay agreed 100 percent with those of virus neutralization, and performed better than published PCR assays. The assay is presented as an alternative rapid, reliable and sensitive test for the detection of ALSV infections, that is equally as effective as virus neutralization tests which take days to complete, and may be a valuable diagnostic test in the eradication and control of ALSV infections in poultry flocks. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A simple mathematical model was presented for membrane adsorption by nanofibrous membrane. • A model based on the combined Carmen-Kozeny equation and Darcy’s law. • A model based on mass balance reproduction of the breakthrough curve of heavy metal ions. • Model parameters were correlated to membrane properties and operating conditions. Abstract The environmental consequences of lead ion accumulation have been linked to detrimental health impacts in humans. Hence, removal of heavy metal (lead, Pb) ions by membrane adsorption/filtration was studied in this work using nanofibrous membranes in which the adsorbent metal-organic framework, MOF-808, was embedded. S-shaped breakthrough curves were obtained experimentally when the heavy metal concentration in the permeate was plotted vs the filtration period. Simple model equations that enable the reproduction of the S-shaped breakthrough curve were derived. It was found that the model equations could simulate the experimental data reasonably well. Attempts were further made to correlate the parameters involved in the model equations to the properties of mixed matrix nanofibrous membranes, including the pore size and pore size distribution, membrane thickness, fiber diameter, the adsorption rate constant, the Langmuir adsorption constant and the maximum adsorption capacity. The model equation parameters were also correlated to the operating conditions including the heavy metal concentration in the feed and the transmembrane pressure difference. It is believed that the model equations, despite this simplicity, can provide deeper insight into the membrane adsorption/filtration phenomena. These equations also contribute to the process design for successful removal of heavy metal ions from the environment to improve health factors for humans. [ABSTRACT FROM AUTHOR]

Discusses a study which described a theoretical framework for the design of asymmetrically doped n-type n-i-p-i- superlattices for subband detector applications in the 10 µm spectral range. Areas where an agreement is found with the subband absorption spectra; Cause of finding pronounced IR-absorption modulation by optical pumping with band-gap radiation; Advantages of the use of n-type n-i-p-i- devices.

Marine hydrokinetic (MHK) devices generate electricity from the motion of tidal and ocean currents, as well as ocean waves, to provide an additional source of renewable energy available to the United States. These devices are a source of anthropogenic noise in the marine ecosystem and must meet regulatory guidelines that mandate a maximum amount of noise that may be generated. In the absence of measured levels from in situ deployments, a model for predicting the propagation of sound from an array of MHK sources in a real environment is essential. A set of coupled, linearized velocity-pressure equations in the time-domain are derived and presented in this paper, which are an alternative solution to the Helmholtz and wave equation methods traditionally employed. Discretizing these equations on a three-dimensional (3D), finite-difference grid ultimately permits a finite number of complex sources and spatially varying sound speeds, bathymetry, and bed composition. The solution to this system of equations has been parallelized in an acoustic-wave propagation package developed at Sandia National Labs, called Paracousti. This work presents the broadband sound pressure levels from a single source in two-dimensional (2D) ideal and Pekeris wave-guides and in a 3D domain with a sloping boundary. The paper concludes with demonstration of Paracousti for an array of MHK sources in a simple wave-guide. [ABSTRACT FROM AUTHOR]

Over the past few decades, the number of people enrolled in doctoral study has increased dramatically across the world. In practical terms, this has meant that universities now receive increasingly diverse students with regard to ethnicity, age, language, culture, and background preparedness for higher degree study. Students can, and often do, begin their doctorates with scant understanding of the precise expectations and rigorous demands of thesis writing. Yet, regardless of academic discipline, successful completion of a doctorate requires a written thesis. To help students master thesis writing requirements, a proliferation of self-help writing books, blogs, specific writing techniques, and programmes have emerged. This paper describes an approach developed at a New Zealand university where a generic doctoral writing programme, the Doctoral Writing Conversation, has evolved to make explicit to students the implicit language understanding that accomplished academic writers use to produce text. Utilising the idea of language as a tool to mediate understanding, the paper will explore how the programme is structured and functions but will also describe some of the insights I have gained along the way. [ABSTRACT FROM AUTHOR]

Huanglongbing ( HLB), associated with the phloem-limited bacterium ' Candidatus Liberibacter asiaticus' (Las), is devastating trees in citrus orchards of Florida. Additionally, Phytophthora nicotianae, omnipresent in citrus soils, causes root rot that reduces water and nutrient uptake by fibrous roots. To investigate fibrous root damage and replacement and canopy size in relation to infection of fibrous roots by Las and P. nicotianae, rootstock seedlings of Swingle citrumelo ( Citrus paradisi × Poncirus trifoliata) were inoculated with Las or P. nicotianae in two greenhouse pot trials. Phytophthora nicotianae caused root damage within 5 weeks post-inoculation, which led to greater reduction of canopy size than for Las-infected seedlings by the end of the experiment. Las increased accumulation of fibrous root biomass at 5 weeks post-root trimming (wpt) in the 2014 trial and at 11 wpt in the 2015 trial. New root length was not consistently increased by Las. Reduced total leaf area of symptomless Las-infected seedlings compared to noninoculated controls might be due to the combined effect of altered carbohydrate allocation between shoots and roots and altered leaf morphology. [ABSTRACT FROM AUTHOR]

We have made direct observations of the Brownian motion of individual nanosized liquid lead inclusions in solid aluminum by in-situ transmission electron microscopy. The process was found to depend strongly on the size of the inclusion and the anisotropy of the interfacial energy. The rate controlling mechanism was the nucleation of steps on facets of the equilibrium shape and the diffusion of Al along the liquid-solid interface. Because the Al-Pb interface undergoes a roughening transition at T r ≈ 820 K, the step nucleation barrier decreases with increasing temperature and vanishes completely at T r . By including the temperature dependence explicitly, we demonstrate that the contribution of the step energy to an Arrhenius plot of the data has a slope greater than the actual activation energy at temperature T by a factor T r /( T r - T ). In addition, we show that the diffusion barrier for interfacial transport makes a substantial contribution. Our analysis reconciles a large discrepancy between activation energies obtained from the temperature and size dependences of the process and solves the apparent paradox posed by the observation that some particles are frozen in non-equilibrium shapes while nearby smaller particles are sufficiently mobile to undergo rapid Brownian motion. [ABSTRACT FROM AUTHOR]

Various modified forms of contour dynamics are used to compute multipolar vortex equilibria, i.e., configurations of constant vorticity patches which are invariant in a steady rotating frame. There are two distinct solution families for "N + 1" point vortex-vortex patch equilibria in which a finite-area central patch is surrounded by N identical point vortices: one with the central patch having oppositesigned vorticity and the other having same-signed vorticity to the satellite vortices. Each solution family exhibits limiting states beyond which no equilibria can be found. At the limiting state, the central patch of a same-signed equilibrium acquires N corners on its boundary. The limiting states of the opposite-signed equilibria have cusp-like behaviour on the boundary of the central patch. Linear stability analysis reveals that the central patch is most linearly unstable as it approaches the limiting states. For equilibria comprising a central patch surrounded by N identical finite-area satellite patches, again two distinct families of solutions exist: one with the central patch and satellite patches having the same-signed vorticity and the other in which they are opposite-signed. In each family, there are two limiting behaviours in which either the central patch or the satellite patches develop corners or cusps. Streamline plots and time-dependent simulations indicate that opposite-signed multipolar equilibria are robust structures and same-signed equilibria are generally less stable. Streamlines also reveal stable and unstable (saddle point) stagnation points, indicating the existence of newequilibria in which additional patches of vorticity are "grown" at the stagnation points. Examples of such equilibria are computed, and a general numerical routine is briefly described for finding even more complex finitearea equilibria. Finally, new nested polygonal vortex equilibria consisting of two sets of polygonally arranged vortex patches (named "N + N" equilibria here) are computed for two distinct cases: one with the corners of the polygons aligned with each other and the other when they are staggered. Various limiting states are computed for these equilibria. Time-dependent simulations reveal that the aligned equilibria are susceptible to instability, while the staggered equilibria survive a relatively long time. In some parameter regimes, following instability, these structures evolve into known structures such as "N + 1" multipolar vortex equilibria and N-polygon co-rotating equilibria. [ABSTRACT FROM AUTHOR]

Emerging evidence highlights that arm movements exert a substantial and functionally relevant contribution on quiet standing balance control in young adults. Ageing is associated with "non-functional" compensatory postural control strategies (i.e., lower limb co-contraction), which in turn, may increase the reliance on an upper body strategy to control upright stance. Thus, the primary purpose of this study was to compare the effects of free versus restricted arm movements on balance performance in young and older adults, during tasks of different difficulty. Fifteen young (mean ± SD age; 21.3 ± 4.2 years) and fifteen older (mean ± SD age; 73.3 ± 5.0 years) adults performed bipedal, semi-tandem and tandem balance tasks under two arm position conditions: restricted arm movements and free arm movements. Centre of pressure (COP) amplitude and frequency were calculated as indices of postural performance and strategy, respectively. Especially in older adults, restriction of arm movement resulted in increased sway amplitude and frequency, which was primarily observed for the mediolateral direction. Further, increasing balance task difficulty raised the arm restriction cost (ARC; a new measure to quantify free vs. restricted arm movement differences in postural control) that was more prominent in older adults. These findings indicate the ARC provides a measure of reliance on the upper body for balance control and that arm movement is important for postural control in older adults, especially during tasks of greater difficulty. • We examined the role of arm movements on balance in young and older adults. • We explored how arm movements moderate the effect of task difficulty on balance. • Older adults were more unstable with restricted arm movements. • Arm movement restriction effects were more pronounced for difficult balance tasks. • We propose a new measure called the 'arm restriction cost' (ARC). [ABSTRACT FROM AUTHOR]

Robotic-assisted transhiatal esophagectomy (RATE) is a technically complex procedure with potential for improved postoperative outcomes. In this report, we describe our experience with RATE in a large case series. A retrospective review was conducted to collect clinical, outcomes and survival data for 100 consecutive patients with esophageal cancer (n = 98) and benign (n = 2) conditions undergoing RATE between March 2007 and December 2014. Progression-free (PFS) and overall (OS) survival were estimated using the Kaplan-Meier curves with comparisons by log-rank tests. Median operative time and estimated blood loss were 264 minutes and 75 mL, respectively. Median intensive care unit stay was 1 day and median length of hospital stay was 8 days. Postoperative complications commonly observed were nonmalignant pleural effusion (38%) and recurrent laryngeal nerve injury (33%); 30 day mortality rate was 2%. Median number of lymph nodes removed during RATE was 17 and R0 resection was achieved in 97.8% patients. At the end of the median follow-up period of 27.7 months, median PFS was 41 months and median OS was 54 months. 1-year and 3-year PFS rates were 82% (95% CI, 75%-89%) and 53% (95% CI, 42%-62%), respectively and OS rates were 95% (95% CI, 91%-99%) and 57% (95% CI, 46%-67%). In our experience, RATE is an effective and safe oncologic surgical procedure in a carefully selected group of patients with acceptable operative time, minimal blood loss, standard postoperative morbidity and adequate PFS and OS profiles. [ABSTRACT FROM AUTHOR]

For valid results in split Hopkinson pressure bar testing, the strain history in the incident bar must be measured at a location where the incident and reflected waves do not overlap. This may prove problematic if the loading pulse is long relative to the length of the incident bar, e.g. due to pulse shaping or when long pressure bars are not available. In this paper an experimental technique for the elimination of overlapping stress waves is presented. By ensuring that the incident wave traverses the bar without noticeable dispersive oscillatory components, a complete pulse history free from superpositioning stress waves can be rapidly constructed via the collation of data from two sets of strain gauges attached at two locations on the incident bar. Experimentation on a sand specimen subsequently validated via finite element modeling demonstrates the advantage of this wave collation technique as it enables the use of longer loading pulses while still satisfying all necessary requirements pertinent to valid Hopkinson bar investigations. [ABSTRACT FROM AUTHOR]

A simple quasigeostrophic model is used to examine the outflow from a river, estuary, or strait into a coastal ocean. As shown by Johnson et al., these quasigeostrophic outflows are accurately described by analytical long-wave solutions. This paper first uses these solutions and contour dynamics simulations to discuss the behavior of coastal outflows. Second, it extends the model and the long-wave theory to consider the effects of ambient currents, tides, winds, or a variable source flux. Third, consideration of the momentum flux at the source is used to understand the turning of the current, showing that steady solutions conserve momentum, hence resolving the momentum imbalance paradox of Pichevin and Nof. Finally, a new numerical scheme to compute steady outflow boundaries is developed. The model focuses on the key dynamics driven by the source velocity and the generation of vorticity as the buoyant fluid adjusts. The simplicity of the model, and insight given by the long-wave solutions, enables a full understanding of the dynamics. The outflows display a range of behaviors, including indefinitely growing near-source bulges, steady boundary profiles with varying offshore width, bidirectional currents, and rarefying or eddy-like leading heads, all of which can be understood with the long-wave theory. Despite the simplicity of the model, the results show good agreement in comparison with observations, experiments, and numerical models. [ABSTRACT FROM AUTHOR]

The Critical Zone is an interdisciplinary theme for environmental research that considers the near surface environment of the Earth and interactions amongst rock, soil, water, air, and living organisms. Critical Zone research initiatives in the United States (US) have met with great success, with multiple Critical Zone Observatories located in a variety of regional field settings at their core. These initiatives have allowed for enormous advances in addressing interdisciplinary environmental science questions based on team collaborations involving experts from various disciplines. The Critical Zone initiative in the US is now being extended to several other countries, but Canada has not been a participant in initial meetings involving various national funding agencies and researchers from different countries. Because physical geographers study a wide range of topics falling under the banner of Critical Zone science (including soils, hydrology, geomorphology, climatology, glaciology, biogeography), they are well poised to be active participants in national strategies for Critical Zone science. Suggestions are provided for moving towards a national strategy for Critical Zone science initiatives in Canada that connect to recent international developments. Vers une stratégie pour la science de la zone critique au Canada La zone critique est un thème interdisciplinaire de la recherche environnementale qui examine le milieu de la proche surface de la Terre et les interactions entre la roche, le sol, l'eau, l'air et les organismes vivants. Les initiatives de recherche en zone critique aux États-Unis ont connu beaucoup de succès grâce à de nombreux observatoires de la zone critique situés au centre de divers dispositifs d'études régionales. Ces initiatives ont permis d'accomplir d'énormes progrès en abordant des questions de science environnementale interdisciplinaire fondées sur la collaboration d'équipes impliquant des spécialistes de diverses disciplines. Les initiatives américaines en zone critique sont maintenant étendues à de nombreux autres pays, mais le Canada n'a pas participé aux premières réunions impliquant divers organismes nationaux de financement ainsi que des chercheurs de différents pays. Comme les géographes spécialisés en géographie physique étudient un large éventail de thèmes placés sous la bannière de la science de la zone critique (y compris les sols, l'hydrologie, la géomorphologie, la climatologie, la glaciologie, la biogéographie), ils sont bien placés pour participer activement aux stratégies nationales pour la science de la zone critique. Des suggestions sont faites dans le but d'adopter une stratégie nationale pour les initiatives concernant la science de la zone critique au Canada qui se rattachent aux récents progrès internationaux. [ABSTRACT FROM AUTHOR]

This paper derives the Whitham modulation equations for the Ostrovsky equation. The equations are then used to analyse localized cnoidal wavepacket solutions of the Ostrovsky equation in the weak rotation limit. The analysis is split into two main parameter regimes: the Ostrovsky equation with normal dispersion relevant to typical oceanic parameters and the Ostrovsky equation with anomalous dispersion relevant to strongly sheared oceanic flows and other physical systems. For anomalous dispersion a new steady, symmetric cnoidal wavepacket solution is presented. The new wavepacket can be represented as a solution of the modulation equations and an analytical solution for the outer solution of the wavepacket is given. For normal dispersion the modulation equations are used to describe the unsteady finite-amplitude wavepacket solutions produced from the rotation-induced decay of a Korteweg-de Vries solitary wave. Again, an analytical solution for the outer solution can be given. The centre of the wavepacket closely approximates a train of solitary waves with the results suggesting that the unsteady wavepacket is a localized, modulated cnoidal wavetrain. The formation of wavepackets from solitary wave initial conditions is considered, contrasting the rapid formation of the packets in anomalous dispersion with the slower formation of unsteady packets under normal dispersion. [ABSTRACT FROM AUTHOR]

Antimicrobial activity of experimental formulations of two structurally different nano-zinc oxide materials, plate-like Zinkicide SG4 and particulate Zinkicide SG6, was evaluated against Xanthomonas citri subsp. citri, the cause of citrus canker. In vitro assay demonstrated Zinkicide SG4 had a twofold lower minimum inhibitory concentration (MIC) against Escherichia coli and X. alfalfae subsp. citrumelonis (62.5 to 250 µg/ml) compared with copper sulfate (250 µg/ml), copper hydroxide (250 to 500 µg/ml), or cuprous oxide/zinc oxide (125 to 250 µg/ml). Zinkicide SG6 had a sevenfold to eightfold lower MIC against Escherichia coli and X. alfalfae subsp. citrumelonis (31 to 250 μg/ml). Leaves of sweet orange (Citrus sinensis) and fruit of ‘Ruby Red’ grapefruit (C. paradisi) were evaluated for citrus canker disease control. A greenhouse assay with foliage demonstrated that spray treatment with Zinkicide reduced citrus canker lesion development after injection-infiltration of X. citri subsp. citri into the leaf intercellular space. In field trials conducted in Southeast Florida in 2014 and 2015, Zinkicide SG4 and SG6 reduction of grapefruit canker incidence exceeded that of cuprous oxide and cuprous oxide/zinc oxide bactericides. Zinkicide formulations were also effective against the fungal diseases, citrus scab (Elsinoe fawcetti) and melanose (Diaporthe citri), on grapefruit. No sign of phytotoxicity to the fruit rind was observed during either season. Antimicrobial activity of Zinkicide for protection of leaves and fruit against X. citri subsp. citri was comparable or exceeded that for commercial copper and zinc oxide formulations which may be attributed to translaminar movement of Zinkicide. [ABSTRACT FROM AUTHOR]

Recent studies show that vertical eddy diffusivity is sufficient on its own to introduce intense horizontal shear layers at sloping ocean margins (Molemaker et al.; Gula et al.; Dewar et al.). These layers influence mesoscale energy and potential vorticity budgets but cannot be fully represented in models without sloping boundaries, no-slip boundary conditions, and sufficiently high resolution. This paper investigates the detachment of these shear layers and their subsequent rolling up into concentrated eddies. These shed eddies, or 'sheddies,' may have significant oceanographic impacts. Their growth is considered using a simple point vortex model that adapts the Brown-Michael model of vortex shedding to quasigeostrophic flow and allows detailed consideration of the vorticity fluxes. The model shows good qualitative agreement with observations and experimental and numerical results. It is applied to a number of examples of well-known cases of sheddy formation, including the Agulhas cyclones, California Undercurrent, and Canary Eddy Corridor, and also is used to investigate the effects of shed vorticity in the growth of the Cook Strait eddy and the interaction of the North Brazil Current rings with the islands of the Lesser Antilles. [ABSTRACT FROM AUTHOR]

Finite-area monopolar vortices which propagate around topography without change in shape are computed for circular seamounts and wells including the limiting cases of each: islands and infinitely deep wells. The time-dependent behaviour of vortex pairs propagating toward circular topography is also examined. Trajectories of point-vortex pairs exterior to the topography are found and compared to trajectories of vortex patches computed using contour dynamics. [ABSTRACT FROM AUTHOR]

The article focuses on queer theory and LGBT history. Topics discussed include research of oral history, Southern African American queer women and feminist historiography. Other topics which includes book "Sweet Tea: Black Gay Men of the South - An Oral History" and queer historiography are also discussed.

Kryptolebias marmoratus exposed to 4 ng l−1 of ethinyl oestradiol ( EE2) for 30 days experienced significant changes in endogenous 17β-oestradiol (E2) and 11-ketotestosterone ( KT) and qualitative changes in gonad morphology. Both hermaphrodites and males showed a significant decrease in E2, whereas only males exhibited a significant decrease in KT. Exposure to EE2 resulted in a decrease in spermatid and spermatocyte density in males and an increase in the number of early stage oocytes in hermaphrodites. [ABSTRACT FROM AUTHOR]

Membrane distillation (MD) is a promising separation technique capable of being used in the desalination of marine and brackish water. Poly(vinylidene fluoride) (PVDF) flat sheet nano-composite membranes were surface modified by coating with electro-spun PVDF nano-fibres to increase the surface hydrophobicity. For this purpose, the nano-composite membrane containing 7 wt.% superhydrophobic SiO 2 nano-particles, which showed the highest flux in our previous work, was first subjected to pore size augmentation by increasing the concentration of the pore forming agent (Di-ionized water). Then, the prepared flat sheet membranes were subjected to nanofibres coating by electro-spinning. The uncoated and coated composite fabricated membranes were characterized using contact angle, liquid entry pressure of water, and scanning electron microscopy. The membranes were further tested for 6 h desalination by direct contact membrane distillation (DCMD) and vacuum membrane distillation (VMD), with a 3.5 wt.% synthetic NaCl aq as the feed. In DCMD the feed liquid and permeate side temperature were maintained at 27.5 °C and 15 °C, respectively. For VMD, the feed liquid temperature was 27 °C and a vacuum of 94.8 kPa was applied on the permeate side. The maximum permeate flux achieved was 3.2 kg/m 2 .h for VMD and 6.5 kg/m 2 .h for DCMD. The salt rejection obtained was higher than 99.98%. The coated membranes showed a more stable flux than the uncoated membranes indicating that the double layered membranes have great potential in solving the pore wetting problem in MD. [ABSTRACT FROM AUTHOR]

In the present work, the effects of heat treatment and strain rate on mechanical behaviour and microstructure evolution of aluminium alloy 6061 have been investigated. The micro-crack initiation and crystallographic texture evolution are obtained from scanning electron microscope and electron back-scatter diffraction experiments. Quasi-static and high strain rate compression tests are conducted on AA6061 specimens that underwent two different heat treatments: the as-received material with the original T6 heat treatment and the heat treated and artificially aged specimens. For the high strain rate compression (∼2000 and ∼4000 s−1) tests, the split Hopkinson pressure bar apparatus is used. It is observed that the additional heat treatment has significantly reduced the yield strength of the material. Furthermore, electron back-scatter diffraction results show that the higher the applied strain rate is, the less significant change will happen to the texture. Scanning electron microscope images show that, for both T6 and HT specimens, the number and size of micro-cracks in the dynamic compressed specimens are smaller than in the quasi-static deformed specimen. Therefore, the strain rate is considered to be the dominant factor in forming micro-cracks. [ABSTRACT FROM AUTHOR]

Polyvinylidene fluoride (PVDF)/SiO 2 flat sheet composite membranes were prepared for vacuum membrane distillation (VMD) by the phase inversion immersion precipitation process. The effect of blending superhydrophobic SiO 2 nanoparticles into the PVDF dope solution was studied. The concentration of the nanoparticles in the dope solution was varied at different wt.% (1, 2, 4, 6, 7, 8 and 10 wt.%). The prepared membranes were characterized by scanning electron microscopy, water contact angle, porosity, liquid entry pressure of water, Fourier transformed infrared spectroscopy, and VMD at feed temperature of 27 °C. The nanoparticles enhanced the membrane performance through a reduction in the sponge-like layer thickness and an increase in surface pore size, leading to increased vapour flux with a maximum at 7 wt.%. The salt rejection was greater than 99.98% when a 35 g/L NaCl solution was used as feed. At this concentration, the smallest thickness of the sponge-like layer and largest macro-voids were also achieved. Beyond 7 wt.%, the sponge-like layer became predominant and the flux was reduced. With a vapour flux increase of up to 4 times (from 0.7 to 2.9 kg/m 2 h) when compared to the neat membrane, this nanocomposite membrane could be of great potential in the desalination process through VMD. [ABSTRACT FROM AUTHOR]

Paraneoplastic hypertrophic osteopathy ( pHO) is known to occur in both canine and human cancer patients. While the pathology of pHO is well-described in the dog, very little information exists regarding the true clinical presentation of dogs affected with pHO. The primary objective of this study was to provide a more comprehensive clinical picture of pHO. To this end, we retrospectively identified 30 dogs and recorded data regarding presenting complaints and physical examination ( PE) findings on the date of pHO diagnosis. As a secondary objective, any blood test results were also collected from the computerized records. The most common clinical signs included leg swelling, ocular discharge and/or episcleral injection, lameness, and lethargy. The most common haematological and serum biochemical abnormalities included anaemia, neutrophilia and elevated alkaline phosphatase. In addition to presenting a more detailed clinical description of pHO in the dog, these data support the previously described haematological, serum biochemical and PE abnormalities published in individual case reports. [ABSTRACT FROM AUTHOR]

The long-time effect of weak rotation on an internal solitary wave is the decay into inertia-gravity waves and the eventual emergence of a coherent, steadily propagating, nonlinear wave packet. There is currently no entirely satisfactory explanation as to why these wave packets form. Here the initial value problem is considered within the context of the Gardner-Ostrovsky, or rotation-modified extended Korteweg-de Vries, equation. The linear Gardner-Ostrovsky equation has maximum group velocity at a critical wave number, often called the zero-dispersion point. It is found here that a nonlinear splitting of the wave-number spectrum at the zero-dispersion point, where energy is shifted into the modulationally unstable regime of the Gardner-Ostrovsky equation, is responsible for the wave-packet formation. Numerical comparisons of the decay of a solitary wave in the Gardner-Ostrovsky equation and a derived nonlinear Schrodinger equation at the zero-dispersion point are used to confirm the spectral splitting. [ABSTRACT FROM AUTHOR]

Weakly-nonlinear unidirectional long internal waves in a non-rotating frame are well described by the Korteweg-de Vries equation (KdV). Within the KdV framework, all isolated monochromatic wavetrains are stable to modulational instability. However, analysis of a coupled nonlinear Schr€odinger equation system (CNLS) has shown that all systems of two co-propagating monochromatic wavetrains in the KdV are modulationally unstable. To take into account the effect of the background rotation of the Earth on long internal waves, this analysis is extended here to derive the CNLS for the rotation-modified KdV, or Ostrovsky, equation. Rotation stabilises wavetrain pairs when the wavelengths of both waves comprising the wavetrains are longer than the linear wave with maximum group velocity. The particular case when the wavetrains have different wavenumbers but the same linear group speed is emphasised. [ABSTRACT FROM AUTHOR]

A simple model for the formation of ocean eddies by flow separation from sharply curved horizontal boundary topography is developed. This is based on the Brown-Michael model for two-dimensional vortex shedding, which is adapted to more realistically model mesoscale oceanic flow by including a deforming free surface. With a free surface, the streamfunction for the flow is not harmonic so the conformal mapping methods used in the standard Brown-Michael approach cannot be used and the problem must be solved numerically. A numerical scheme is developed based on a Chebyshev spectral method for the streamfunction partial differential equation and a second order implicit timestepping scheme for the vortex position ordinary differntial equations. This method is used to compute shed vortex trajectories for three background flows: (A) a steady flow around a semi-infinite plate, (B) a free vortex moving around a semi-infinite plate, and (C) a free vortex moving around a right-angled wedge. In (A), the inclusion of surface deformation dramatically slows the vortex and changes its trajectory from a straight path to a curved one. In (B) and (C), without the inclusion of flow separation, free vortices traverse fully around the tip along symmetrical trajectories. With the effects of flow separation included, very different trajectories are found: for all values of the model parameter--the Rossby radius--the free and shed vortices pair up and move off to infinity without passing around the tip. Their final propagation angle depends strongly and monotonically on the Rossby radius. [ABSTRACT FROM AUTHOR]

The physics behind the strain-released buckling patterns including telephone cords and straightsided wrinkles with and without cracks, as experimentally observed in sputter-deposited Ti-Si-N thin films on Si substrates, is investigated with model-based simulations by varying the mechanical properties of the interface. Our calculations reveal that the location of the cracks depends on the normal stiffness, the interfacial toughness, and the normal strength of the cohesive interface. These properties determine the geometrical shape of the buckles such as width, wavelength, and deflection, and hence the local bending-induced tensile stresses. Buckling patterns with cracks at the apexes occur for low-stiffness interfaces as well as for high-stiffness interfaces with high toughness. On the other hand, cracks at the bottom of the buckles are more likely to occur for interfaces with high stiffness and low toughness. By using an elastic material model with a fracture criterion for brittle behavior, we demonstrate that the crack will follow the path where the bending-induced principal stress exceeds the flexural strength of the film. [ABSTRACT FROM AUTHOR]

Many types of zeolites have been developed based on kaolinite in previous years. This review focuses on the current reports of kaolinite-based zeolites and the important factors in their synthesis. Among the factors discussed in this review are the effect of SiO2/Al2O3 (Si/Al) molar ratio of the gel mixture, metakaolinization time and temperature, aging condition, alkalinity, and crystallization time and temperature. This review only covers the most recent kaolinite-based zeolite papers published from 2005 to present. A brief discussion on the evolution of zeolites is also included. [ABSTRACT FROM AUTHOR]

The long time effect of weak rotation on an internal solitary wave is the decay into inertia-gravity waves and the eventual formation of a localised wavepacket. Here this initial value problem is considered within the context of the Ostrovsky, or the rotationmodified Korteweg-de Vries (KdV), equation and a numerical method for obtaining accurate wavepacket solutions is presented. The flow evolutions are described in the regimes of relatively-strong and relatively-weak rotational effects. When rotational effects are relatively strong a second-order soliton solution of the nonlinear Schrödinger equation accurately predicts the shape, and phase and group velocities of the numerically determined wavepackets. It is suggested that these solitons may form from a local Benjamin-Feir instability in the inertia-gravity wave-train radiated when a KdV solitary wave rapidly adjusts to the presence of strong rotation. When rotational effects are relatively weak the initial KdV solitary wave remains coherent longer, decaying only slowly due to weak radiation and modulational instability is no longer relevant. Wavepacket solutions in this regime appear to consist of a modulated KdV soliton wavetrain propagating on a slowly varying background of finite extent. [ABSTRACT FROM AUTHOR]

The article presents information on black gay studies in the U.S. Among the works cited are "Brother to Brother: Writings of Black Gay Men," edited by Essex Hemphill in 1991, "Tongues Untied," by Marlon Rigg, "Black Queer Studies: A Critical Anthology," edited by Mae G. Henderson, and "A Taste of Brown Sugar: Black Women in Pornography," by Mireille Miller-Young.