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Physics-based first-principles pressure-volume-temperature equations of state (EOS) exist for solids and gases but not for liquids due to the long-standing fundamental problems involved in liquid theory. Current EOS models that are applicable to liquids and supercritical fluids at liquid-like density under conditions relevant to planetary interiors and industrial processes are complex empirical models with many physically meaningless adjustable parameters. Here, we develop a generally applicable physics-based (GAP) EOS for liquids including supercritical fluids at liquid-like density. The GAP equation is explicit in the internal energy, and hence links the most fundamental macroscopic static property of fluids, the pressure-volume-temperature EOS, to their key microscopic property: the molecular hopping frequency or liquid relaxation time, from which the internal energy can be obtained. We test our GAP equation against available experimental data in several different ways and find good agreement. Our GAP equation, unavoidably and similarly to solid EOS, contains a semi-empirical term giving the energy of the static sample as a function of volume only (EST(V)). Our testing includes studies along isochores, in order to examine the validity of the GAP equation independently of the validity of any function we may choose to utilize forEST(V). The only other adjustable parameter in the equation is the Grüneisen parameter for the fluid. We observe that the GAP equation is similar to the Mie-Grüneisen solid EOS in a wide range of the liquid phase diagram. This similarity is ultimately related to the condensed state of these two phases. On the other hand, the differences between the GAP equation and EOS for gases are fundamental. Finally, we identify the key gaps in the experimental data that need to be filled in to proceed further with the liquid EOS.
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This paper explores the degree to which heterodox economics can contribute to the development and use of climate-economy integrated assessment models. To do so, it introduces the field of integrated assessment modeling, with a focus on the core economic methodology used by various types of models. It then summarizes some of the literature critiquing these models and how they inform policy. The paper then provides an extended classification of ways in which heterodox economics could be applied to climate-economy models and presents a number of storylines, or pathways, which could be created using insights and methods from heterodox schools. The paper concludes with an assessment of the scope for heterodox economics to answer the criticisms of climate-economy models, finding that despite not resolving all issues, the heterodoxy has a substantial role to play.
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We have developed generalized methods for electrical substitution optical measurements, as well as cryogenic detectors which can be used to implement them. The new methods detailed here enable measurement of arbitrary periodic waveforms by an electrical substitution radiometer (ESR), which means that spectral and dynamic optical power can be absolutely calibrated directly by a primary standard detector. Cryogenic ESRs are not often used directly by researchers for optical calibrations due to their slow response times and cumbersome operation. We describe two types of ESRs with fast response times, including newly developed cryogenic bolometers with carbon nanotube absorbers, which are manufacturable by standard microfabrication techniques. These detectors have response times near 10 ms, spectral coverage from the ultraviolet to far-infrared, and are ideal for use with generalized electrical substitution. In our first tests of the generalized electrical substitution method with FTS, we have achieved uncertainty in detector response of 0.13 % (k=1) and total measurement uncertainty of 1.1 % (k=1) in the mid-infrared for spectral detector responsivity calibrations. The generalized method and fast detectors greatly expand the range of optical power calibrations which can be made using a wideband primary standard detector, which can shorten calibration chains and improve uncertainties.
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We have demonstrated the first continuous-scan electrical substitution Fourier transform spectrometer (ES-FTS), which serves initially as an apparatus for absolute spectral responsivity calibrations of detectors over the wavelength range from 1.5â µm to 11â µm. We present data on the realization of a spectral detector-comparator system with high accuracy, high dynamic range, high spectral resolution and fast measurement in the infrared region, which is tied directly to an absolute power scale through electrical substitution. The ES-FTS apparatus employs a commercial Fourier transform spectrometer and a custom electrical substitution bolometer detector to enable spectrally-resolved absolute optical power measurements. A generalization of electrical substitution techniques enables determination of the voltage waveform that must be applied to the bolometer's electrical heater to cancel the optical signal from a Michelson interferometer in order to quantify the time-dependent optical power incident on the bolometer. The noise floor of the electrical substitution bolometer is on the order of 10 pW/Hz½ and its response is expected to be linear from the noise floor to 1â mW. A direct comparison between a pyroelectric standard detector and the ES-FTS has been performed, and experimental results reported here show great potential for this technique.
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Health research is published at a breathtaking pace and quantity; however, even when research is systematically developed into best practices and/or clinical guidelines, it often is not implemented into practice. Project ECHO (Extension for Community Healthcare Outcomes) is an evidence-based professional development approach that can help nurses to stay current and apply new knowledge to practice. The purpose of this article is to describe ECHO as a model for professional development and capacity building through learning networks. This article describes the ECHO model, evidence supporting its use, the infrastructure needed to implement an ECHO network, and two nursing ECHO learning networks. [J Contin Educ Nurs. 2021;52(4):198-204.].
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Bacharelado em Enfermagem , Competência Clínica , Educação Continuada em Enfermagem , Humanos , AprendizagemRESUMO
BACKGROUND: Healthcare worker (HCW) behaviours, such as the sequence of their contacts with surfaces and hand hygiene moments, are important for understanding disease transmission. AIM: To propose a method for recording sequences of HCW behaviours during mock vs actual procedures, and to evaluate differences for use in infection risk modelling and staff training. METHODS: Procedures for three types of care were observed under mock and actual settings: intravenous (IV) drip care, observational care and doctors' rounds on a respiratory ward in a university teaching hospital. Contacts and hand hygiene behaviours were recorded in real-time using either a handheld tablet or video cameras. FINDINGS: Actual patient care demonstrated 70% more surface contacts than mock care. It was also 2.4 min longer than mock care, but equal in terms of patient contacts. On average, doctors' rounds took 7.5 min (2.5 min for mock care), whilst auxiliary nurses took 4.9 min for observational care (2.4 min for mock care). Registered nurses took 3.2 min for mock IV care and 3.8 min for actual IV care; this translated into a 44% increase in contacts. In 51% of actual care episodes and 37% of mock care episodes, hand hygiene was performed before patient contact; in comparison, 15% of staff delivering actual care performed hand hygiene after patient contact on leaving the room vs 22% for mock care. The number of overall touches in the patient room was a modest predictor of hand hygiene. Using a model to predict hand contamination from surface contacts for Staphylococcus aureus, Escherichia coli and norovirus, mock care underestimated micro-organisms on hands by approximately 30%.
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Infecção Hospitalar , Higiene das Mãos , Controle de Infecções , Fidelidade a Diretrizes , Mãos , Desinfecção das Mãos , Pessoal de Saúde , Humanos , Assistência ao Paciente , Simulação de Paciente , Quartos de PacientesAssuntos
Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Transmissão de Doença Infecciosa/prevenção & controle , Máscaras/estatística & dados numéricos , Máscaras/normas , Teste de Materiais/estatística & dados numéricos , Teste de Materiais/normas , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Betacoronavirus , COVID-19 , Humanos , Comportamento de Redução do Risco , SARS-CoV-2RESUMO
N-Methylpyrrolidone is one of several chemotypes that have been described as a mimetic of acetyl-lysine in the development of bromodomain inhibitors. In this paper, we describe the synthesis of a 4-phenyl substituted analogue - 1-methyl-4-phenylpyrrolidin-2-one - and the use of aryl substitution reactions as a divergent route for derivatives. Ultimately, this has led to structurally complex, chiral compounds with progressively improved affinity as inhibitors of bromodomain-containing protein 4.
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Proteínas de Ciclo Celular/antagonistas & inibidores , Desenho de Fármacos , Pirrolidinonas/farmacologia , Fatores de Transcrição/antagonistas & inibidores , Proteínas de Ciclo Celular/metabolismo , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Transferência Ressonante de Energia de Fluorescência , Humanos , Modelos Moleculares , Estrutura Molecular , Pirrolidinonas/química , Relação Estrutura-Atividade , Fatores de Transcrição/metabolismoRESUMO
N-Methylpyrrolidone is a solvent molecule which has been shown to compete with acetyl-lysine-containing peptides for binding to bromodomains. From crystallographic studies, it has also been shown to closely mimic the acetamide binding motif in several bromodomains, but has not yet been directly pursued as a fragment in bromodomain inhibition. In this paper, we report the elaboration of N-methylpyrrolidone as a potential lead in fragment-based drug design. Firstly, N-methylpyrrolidone was functionalised to provide points for chemical elaboration. Then, the moiety was incorporated into analogues of the reported bromodomain inhibitor, Olinone. X-ray crystallography revealed that the modified analogues showed comparable binding affinity and structural mimicry to Olinone in the bromodomain binding site.
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Proteínas de Ciclo Celular/química , Desenho de Fármacos , Pirrolidinonas/síntese química , Fatores de Transcrição/química , Sítios de Ligação , Proteínas de Ciclo Celular/metabolismo , Cristalografia por Raios X , Transferência Ressonante de Energia de Fluorescência , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Modelos Moleculares , Estrutura Molecular , Ligação Proteica , Conformação Proteica , Pirrolidinonas/química , Relação Estrutura-Atividade , Fatores de Transcrição/metabolismoRESUMO
We have studied in detail the transition from gas-like to rigid liquid-like behavior in supercritical N2 at 300 K (2.4 TC). Our study combines neutron diffraction and Raman spectroscopy with ab initio molecular dynamics simulations. We observe a narrow transition from gas-like to rigid liquid-like behavior at ca. 150 MPa, which we associate with the Frenkel line. Our findings allow us to reliably characterize the Frenkel line using both diffraction and spectroscopy methods, backed up by simulation, for the same substance. We clearly lay out what parameters change, and what parameters do not change, when the Frenkel line is crossed.
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Hybrid systems are traditionally difficult to identify and analyse using classical dynamical systems theory. Moreover, recently developed model identification methodologies largely focus on identifying a single set of governing equations solely from measurement data. In this article, we develop a new methodology, Hybrid-Sparse Identification of Nonlinear Dynamics, which identifies separate nonlinear dynamical regimes, employs information theory to manage uncertainty and characterizes switching behaviour. Specifically, we use the nonlinear geometry of data collected from a complex system to construct a set of coordinates based on measurement data and augmented variables. Clustering the data in these measurement-based coordinates enables the identification of nonlinear hybrid systems. This methodology broadly empowers nonlinear system identification without constraining the data locally in time and has direct connections to hybrid systems theory. We demonstrate the success of this method on numerical examples including a mass-spring hopping model and an infectious disease model. Characterizing complex systems that switch between dynamic behaviours is integral to overcoming modern challenges such as eradication of infectious diseases, the design of efficient legged robots and the protection of cyber infrastructures.
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We have designed and constructed a novel electric discharge machine designed primarily for the preparation of sample chambers in rhenium and stainless steel gaskets for diamond anvil cell experiments. Our design combines automatic stage movement with relatively low voltage (100 V) operation and routinely achieves a drilling/erosion speed of approximately 0.4 µm s-1. The machine is used for preparing 100 µm diameter sample chambers for diamond anvil cell experiments with 250 µm culets and has also been used to prepare 50 µm diameter sample chambers for diamond anvil cell experiments with 100 µm culets to access a pressure of 165 GPa.
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We have designed, fabricated, and measured infrared trap detectors made from arsenic-doped silicon (Si:As) blocked impurity band (BIB) photodetectors. These trap detectors are composed of two detectors in a wedge geometry, with an entrance aperture diameter of either 1 or 3 mm. The detectors were calibrated for quantum efficiency against a pyroelectric reference detector using a Fourier transform spectral comparator system, and etalon effects and spatial uniformity of the traps were also quantified. Measurements of the traps at a temperature of 10 K show that nearly ideal external quantum efficiency (>90%) can be attained over much of the range from 4 to 24 µm, with significant responsivity from 2 to 30 µm. The traps exhibited maximum etalon oscillations of only 2%, which is about 10 times smaller amplitude than those of the single Si:As BIB detectors measured under similar conditions. Spatial nonuniformity across the entrance apertures of the traps was about 1%. The combination of high detectivity, wideband wavelength coverage, spectral flatness, and spatial uniformity make these trap detectors an excellent reference detector for spectrally resolved measurements and radiometric calibrations over the near- to far-infrared wavelength range.
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In previous work, we built a neuromechanical model for insect locomotion in the horizontal plane, containing a central pattern generator, motoneurons, muscles actuating jointed legs, and rudimentary proprioceptive feedback. This was subsequently simplified to a set of 24 phase oscillators describing motoneuronal activation of agonist-antagonist muscle pairs, which facilitates analyses and enables simulations over multi-dimensional parameter spaces. Here we use the phase-reduced model to study dynamics and stability over the typical speed range of the cockroach Blaberus discoidalis, the effects of feedback on response to perturbations, strategies for turning, and a trade-off between stability and maneuverability. We also compare model behavior with experiments on lateral perturbations, changes in body mass and moment of inertia, and climbing dynamics, and we present a simple control strategy for steering using exteroceptive feedback.
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Fenômenos Biomecânicos/fisiologia , Retroalimentação Sensorial/fisiologia , Locomoção/fisiologia , Modelos Biológicos , Neurônios Motores/fisiologia , Animais , Baratas/fisiologia , Vias Neurais/fisiologia , Dinâmica não LinearRESUMO
OBJECTIVE: To measure in vitro fertilization (IVF) outcomes following 24-chromosome singleânucleotide-polymorphism (SNP)-based preimplantation genetic testing for aneuploidy (PGT-A) and euploid embryo transfer. DESIGN: Retrospective. SETTING: Fertility clinics and laboratory. PATIENT(S): Women 20-46 years of age undergoing IVF treatment. INTERVENTION(S): Twenty-four-chromosome SNP-based PGT-A of day 5/6 embryo biopsies. MAIN OUTCOME MEASURE(S): Maternal age-stratified implantation, clinical pregnancy, and live birth rates per embryo transfer; miscarriage rates; and number of embryo transfers per patient needed to achieve a live birth. RESULT(S): An implantation rate of 69.9%, clinical pregnancy rate per transfer of 70.6%, and live birth rate per transfer of 64.5% were observed in 1,621 nondonor frozen cycles with the use of SNP-based PGT-A. In addition, SNP-based PGT-A outcomes, when measured per cycle with transfer, remained relatively constant across all maternal ages; when measured per cycle initiated, they decreased as maternal age increased. Miscarriage rates were â¼5% in women ≤40 years old. No statistically significant differences in pregnancy outcomes were found for single-embryo transfers (SET) versus double-embryo transfers with SNP-based PGT-A. On average, 1.38 embryo transfers per patient were needed to achieve a live birth in nondonor cycles. CONCLUSION(S): Our findings that SNP-based PGT-A can mitigate the negative effects of maternal age on IVF outcomes in cycles with transfer, and that pregnancy outcomes from SET cycles are not significantly different from those of double-embryo transfer cycles, support the use of SET when transfers are combined with SNP-based PGT-A.
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Aneuploidia , Fertilização in vitro/estatística & dados numéricos , Testes Genéticos , Polimorfismo de Nucleotídeo Único , Resultado da Gravidez/epidemiologia , Diagnóstico Pré-Implantação , Aborto Espontâneo/epidemiologia , Aborto Espontâneo/genética , Adulto , Cromossomos Humanos , Hibridização Genômica Comparativa/métodos , Hibridização Genômica Comparativa/estatística & dados numéricos , Feminino , Testes Genéticos/métodos , Testes Genéticos/estatística & dados numéricos , Humanos , Pessoa de Meia-Idade , Gravidez , Resultado da Gravidez/genética , Taxa de Gravidez , Diagnóstico Pré-Implantação/efeitos adversos , Diagnóstico Pré-Implantação/métodos , Diagnóstico Pré-Implantação/estatística & dados numéricos , Adulto JovemRESUMO
We review recent work aimed at understanding dynamical and thermodynamic properties of liquids and supercritical fluids. The focus of our discussion is on solid-like transverse collective modes, whose evolution in the supercritical fluids enables one to discuss the main properties of the Frenkel line separating rigid liquid-like and non-rigid gas-like supercritical states. We subsequently present recent experimental evidence of the Frenkel line showing that structural and dynamical crossovers are seen at a pressure and temperature corresponding to the line as predicted by theory and modelling. Finally, we link dynamical and thermodynamic properties of liquids and supercritical fluids by the new calculation of liquid energy governed by the evolution of solid-like transverse modes. The disappearance of those modes at high temperature results in the observed decrease of heat capacity.
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INTRODUCTION: This pilot trial will inform the design and methods of a future full-scale randomized controlled trial (RCT) and examine the feasibility, acceptability and fidelity of the Increasing Physical activity in Older People with chronic Pain (iPOPP) intervention, a healthcare assistant (HCA)-supported intervention to promote walking in older adults with chronic musculoskeletal pain in a primary care setting. METHODS AND ANALYSIS: The iPOPP study is an individually randomized, multicentre, three-parallel-arm pilot RCT. A total of 150 participants aged ≥65 years with chronic pain in one or more index sites will be recruited and randomized using random permuted blocks, stratified by general practice, to: (i) usual care plus written information; (ii) pedometer plus usual care and written information; or (iii) the iPOPP intervention. A theoretically informed mixed-methods approach will be employed using semi-structured interviews, audio recordings of the HCA consultations, self-reported questionnaires, case report forms and objective physical activity data collection (accelerometry). Follow-up will be conducted 12 weeks post-randomization. Collection of the quantitative data and statistical analysis will be performed blinded to treatment allocation, and analysis will be exploratory to inform the design and methods of a future RCT. Analysis of the HCA consultation recordings will focus on the use of a checklist to determine the fidelity of the iPOPP intervention delivery, and the interview data will be analysed using a constant comparison approach in order to generate conceptual themes focused around the acceptability and feasibility of the trial, and then mapped to the Theoretical Domains Framework to understand barriers and facilitators to behaviour change. A triangulation protocol will be used to integrate quantitative and qualitative data and findings.
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Dor Crônica/terapia , Terapia por Exercício , Dor Musculoesquelética/terapia , Atenção Primária à Saúde , Caminhada , Idoso , Pessoal Técnico de Saúde/educação , Estudos de Viabilidade , Humanos , Aceitação pelo Paciente de Cuidados de Saúde , Projetos PilotoRESUMO
We develop an algorithm for model selection which allows for the consideration of a combinatorially large number of candidate models governing a dynamical system. The innovation circumvents a disadvantage of standard model selection which typically limits the number of candidate models considered due to the intractability of computing information criteria. Using a recently developed sparse identification of nonlinear dynamics algorithm, the sub-selection of candidate models near the Pareto frontier allows feasible computation of Akaike information criteria (AIC) or Bayes information criteria scores for the remaining candidate models. The information criteria hierarchically ranks the most informative models, enabling the automatic and principled selection of the model with the strongest support in relation to the time-series data. Specifically, we show that AIC scores place each candidate model in the strong support, weak support or no support category. The method correctly recovers several canonical dynamical systems, including a susceptible-exposed-infectious-recovered disease model, Burgers' equation and the Lorenz equations, identifying the correct dynamical system as the only candidate model with strong support.
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We have studied the compressibility and stability of different ß-titanium alloys at high pressure, including binary Ti-Mo, Ti-24Nb-4Zr-8Sn (Ti2448) and Ti-36Nb-2Ta-0.3O (gum metal). We observed stability of the ß phase in these alloys to 40 GPa, well into the ω phase region in the P-T diagram of pure titanium. Gum metal was pressurised above 70 GPa and forms a phase with a crystal structure similar to the η phase of pure Ti. The bulk moduli determined for the different alloys range from 97 ± 3 GPa (Ti2448) to 124 ± 6 GPa (Ti-16.8Mo-0.13O).
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We report experimental evidence for a crossover between a liquidlike state and a gaslike state in fluid methane (CH_{4}). This crossover is observed in all of our experiments, up to a temperature of 397 K, 2.1 times the critical temperature of methane. The crossover has been characterized with both Raman spectroscopy and x-ray diffraction in a number of separate experiments, and confirmed to be reversible. We associate this crossover with the Frenkel line-a recently hypothesized crossover in dynamic properties of fluids extending to arbitrarily high pressure and temperature, dividing the phase diagram into separate regions where the fluid possesses liquidlike and gaslike properties. On the liquidlike side the Raman-active vibration increases in frequency linearly as pressure is increased, as expected due to the repulsive interaction between adjacent molecules. On the gaslike side this competes with the attractive van der Waals potential leading the vibration frequency to decrease as pressure is increased.