RESUMO
SignificanceMany bad decisions and their devastating consequences could be avoided if people used optimal decision strategies. Here, we introduce a principled computational approach to improving human decision making. The basic idea is to give people feedback on how they reach their decisions. We develop a method that leverages artificial intelligence to generate this feedback in such a way that people quickly discover the best possible decision strategies. Our empirical findings suggest that a principled computational approach leads to improvements in decision-making competence that transfer to more difficult decisions in more complex environments. In the long run, this line of work might lead to apps that teach people clever strategies for decision making, reasoning, goal setting, planning, and goal achievement.
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Inteligência Artificial , Tomada de Decisões , HumanosRESUMO
BACKGROUND: Whole-body magnetic resonance imaging (WB-MRI) is an increasingly used guideline-based imaging modality for oncological and non-oncological pathologies during childhood and adolescence. While diffusion-weighted imaging (DWI), a part of WB-MRI, enhances image interpretation and improves sensitivity, it also requires the longest acquisition time during a typical WB-MRI scan protocol. Interleaved short tau inversion recovery (STIR) DWI with simultaneous multi-slice (SMS) acquisition is an effective way to speed up examinations. OBJECTIVE: In this study of children and adolescents, we compared the acquisition time, image quality, signal-to-noise ratio (SNR) and apparent diffusion coefficient (ADC) values of an interleaved STIR SMS-DWI sequence with a standard non-accelerated DWI sequence for WB-MRI. MATERIALS AND METHODS: Twenty children and adolescents (mean age: 13.9 years) who received two WB-MRI scans at a maximum interval of 18 months, consisting of either standard DWI or SMS-DWI MRI, respectively, were included. For quantitative evaluation, the signal-to-noise ratio (SNR) was determined for b800 images and ADC maps of seven anatomical regions. Image quality evaluation was independently performed by two experienced paediatric radiologists using a 5-point Likert scale. The measurement time per slice stack, pause between measurements including shim and total measurement time of DWI for standard DWI and SMS-DWI were extracted directly from the scan data. RESULTS: When including the shim duration, the acquisition time for SMS-DWI was 43% faster than for standard DWI. Qualitatively, the scores of SMS-DWI were higher in six locations in the b800 images and four locations in the ADC maps. There was substantial agreement between both readers, with a Cohen's kappa of 0.75. Quantitatively, the SNR in the b800 images and the ADC maps did not differ significantly from one another. CONCLUSION: Whole body-MRI with SMS-DWI provided equivalent image quality and reduced the acquisition time almost by half compared to the standard WB-DWI protocol.
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Imageamento por Ressonância Magnética , Imagem Corporal Total , Humanos , Adolescente , Criança , Estudos Prospectivos , Imagem Corporal Total/métodos , Reprodutibilidade dos Testes , Imagem de Difusão por Ressonância Magnética/métodosRESUMO
One of the most unique and impressive feats of the human mind is its ability to discover and continuously refine its own cognitive strategies. Elucidating the underlying learning and adaptation mechanisms is very difficult because changes in cognitive strategies are not directly observable. One important domain in which strategies and mechanisms are studied is planning. To enable researchers to uncover how people learn how to plan, we offer a tutorial introduction to a recently developed process-tracing paradigm along with a new computational method for measuring the nature and development of a person's planning strategies from the resulting process-tracing data. Our method allows researchers to reveal experience-driven changes in people's choice of individual planning operations, planning strategies, strategy types, and the relative contributions of different decision systems. We validate our method on simulated and empirical data. On simulated data, its inferences about the strategies and the relative influence of different decision systems are accurate. When evaluated on human data generated using our process-tracing paradigm, our computational method correctly detects the plasticity-enhancing effect of feedback and the effect of the structure of the environment on people's planning strategies. Together, these methods can be used to investigate the mechanisms of cognitive plasticity and to elucidate how people acquire complex cognitive skills such as planning and problem-solving. Importantly, our methods can also be used to measure individual differences in cognitive plasticity and examine how different types (pedagogical) interventions affect the acquisition of cognitive skills.
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Aprendizagem , Resolução de Problemas , Humanos , AtitudeRESUMO
Physician Assistants (PAs) are a relatively new addition to the Ontario healthcare system. To understand the impact of the PA role, this study investigated supervising physician satisfaction and perception of PA roles, interprofessional team integration, pandemic supports, and barriers and enablers to PA employment. A web-based survey was conducted of 118 physician supervisors of Ontario PA education program alumni. PAs were employed in a variety of community and hospital settings. In addition to patient care, PAs were involved teaching (65.6%), quality improvement (52.7%), and mentorship (40.0%). Overall, 92.9% of physicians indicated they were satisfied with their PAs. Important barriers to hiring PAs included maintaining PA salaries, billing limitations, and PA shortages. PAs have established themselves as valuable and competent members of healthcare teams. By continuing to explore the enablers and barriers to PA employment from the physician perspective, health leaders can continue to optimize and support role integration.
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Assistentes Médicos , Médicos , Humanos , Ontário , Atenção à Saúde , Assistentes Médicos/educação , Satisfação PessoalRESUMO
Squids maneuver to capture prey, elude predators, navigate complex habitats and deny rivals access to mates. Despite the ecological importance of this essential locomotive function, limited quantitative data on turning performance and wake dynamics of squids are available. To better understand the contribution of the jet, fins and arms to turns, the role of orientation (i.e. arms first versus tail first) in maneuvering, and the relationship between jet flow and turning performance, kinematic and 3D velocimetry data were collected in tandem from brief squid, Lolliguncula brevis. The pulsed jet, which can be vectored to direct flows, was the primary driver of most turning behaviors, producing flows with the highest impulse magnitude and angular impulse about the main axis of the turn (yaw) and secondary axes (roll and pitch). The fins and keeled arms played subordinate but important roles in turning performance, contributing to angular impulse, stabilizing the maneuver along multiple axes and/or reducing rotational resistance. Orientation affected turning performance and dynamics, with tail-first turns being associated with greater impulse and angular impulse, longer jet structures, higher jet velocities and greater angular turning velocities than arms-first turns. Conversely, arms-first turns involved shorter, slower jets with less impulse, but these directed short pulses resulted in lower minimum length-specific turning radii. Although the length-to-diameter ratio (L/D) of ejected jet flow was a useful metric for characterizing vortical flow features, it, by itself, was not a reliable predictor of angular velocity or turning radii, which reflects the complexity of the squid multi-propulsor system.
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Decapodiformes , Natação , Nadadeiras de Animais , Animais , Fenômenos Biomecânicos , ReologiaRESUMO
OBJECTIVES: To compare the diagnostic value of ultrashort echo time (UTE) magnetic resonance imaging (MRI) for the lung versus the gold standard computed tomography (CT) and two T1-weighted MRI sequences in children. METHODS: Twenty-three patients with proven oncologic disease (14 male, 9 female; mean age 9.0 + / - 5.4 years) received 35 low-dose CT and MRI examinations of the lung. The MRI protocol (1.5-T) included the following post-contrast sequences: two-dimensional (2D) incoherent gradient echo (GRE; acquisition with breath-hold), 3D volume interpolated GRE (breath-hold), and 3D high-resolution radial UTE sequences (performed during free-breathing). Images were evaluated by considering image quality as well as distinct diagnosis of pulmonary nodules and parenchymal areal opacities with consideration of sizes and characterisations. RESULTS: The UTE technique showed significantly higher overall image quality, better sharpness, and fewer artefacts than both other sequences. On CT, 110 pulmonary nodules with a mean diameter of 4.9 + / - 2.9 mm were detected. UTE imaging resulted in a significantly higher detection rate compared to both other sequences (p < 0.01): 76.4% (84 of 110 nodules) for UTE versus 60.9% (67 of 110) for incoherent GRE and 62.7% (69 of 110) for volume interpolated GRE sequences. The detection of parenchymal areal opacities by the UTE technique was also significantly higher with a rate of 93.3% (42 of 45 opacities) versus 77.8% (35 of 45) for 2D GRE and 80.0% (36 of 45) for 3D GRE sequences (p < 0.05). CONCLUSION: The UTE technique for lung MRI is favourable in children with generally high diagnostic performance compared to standard T1-weighted sequences as well as CT. Key Points ⢠Due to the possible acquisition during free-breathing of the patients, the UTE MRI sequence for the lung is favourable in children. ⢠The UTE technique reaches higher overall image quality, better sharpness, and lower artefacts, but not higher contrast compared to standard post-contrast T1-weighted sequences. ⢠In comparison to the gold standard chest CT, the detection rate of small pulmonary nodules small nodules ≤ 4 mm and subtle parenchymal areal opacities is higher with the UTE imaging than standard T1-weighted sequences.
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Imageamento Tridimensional , Imageamento por Ressonância Magnética , Adolescente , Suspensão da Respiração , Criança , Pré-Escolar , Feminino , Humanos , Pulmão/diagnóstico por imagem , Masculino , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND: Post-processing software can be used in digital radiography to achieve higher image quality, especially in cases of scattered radiation. SimGrid is a grid-like software based on a Convolutional Neuronal Network that estimates the distribution and degree of scattered radiation in radiographs and thus improves image quality by simulating an anti-scatter grid. S-Enhance is an algorithm programmed to improve contrast visibility of foreign material. OBJECTIVE: The objective of this study was to evaluate the SimGrid and S-Enhance digital radiography post-processing methods for neonatology and paediatric intensive care. MATERIALS AND METHODS: Two hundred and ten radiographs from the neonatal (n = 101, 0 to 6 months of age) and paediatric (n = 109, 6 months to 18 years of age) intensive care units performed in daily clinical routine using a mobile digital radiography system were post-processed with one of the algorithms, anonymized and then evaluated comparatively by two experienced paediatric radiologists. For every radiograph, patient data and exposure data were collected and analysed. RESULTS: Analysis of different radiographs showed that SimGrid significantly improves image quality for patients with a weight above 10 kg (range: 10-30 kg: odds ratio [OR] = 6.683, P < 0.0001), especially regarding the tracheobronchial system, intestinal gas, and bones. Utilizing S-Enhance significantly advances the assessment of foreign material (OR = 136.111, P < 0.0001) and bones (OR = 34.917, P < 0.0001) for children of all ages and weight, whereas overall image quality decreases. CONCLUSION: SimGrid offers a differentiated spectrum in image improvement for children beyond the neonatal period whereas S-Enhance especially improves visibility of foreign material and bones for all patients.
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Algoritmos , Intensificação de Imagem Radiográfica , Criança , Cuidados Críticos , Humanos , Recém-Nascido , Doses de Radiação , Intensificação de Imagem Radiográfica/métodos , Radiografia , Radiografia Torácica , Espalhamento de RadiaçãoRESUMO
OBJECTIVE: To assess the proportion of academic family physicians using e-mail with patients and to explore related attitudes, barriers, and facilitators. DESIGN: A 47-item questionnaire was created after a literature review, discussions with study team members, pretesting, and pilot testing. The questionnaire was disseminated electronically from June to August 2017. SETTING: Ontario. PARTICIPANTS: All family physicians affiliated with the Department of Family and Community Medicine at the University of Toronto. MAIN OUTCOME MEASURES: Physician practices using e-mail (including barriers to and facilitators of e-mail use with patients), use of e-mail with other health care providers, use of communication technologies other than e-mail, and demographic and practice information. RESULTS: A total of 1553 surveys were disseminated and 865 responses received (56% response rate). Overall, 610 respondents met inclusion criteria. Of these respondents, 43% (265 of 610) personally sent e-mails to patients in a typical week. An additional 21% (126 of 610) reported that they did not personally e-mail patients, but their clinic staff did. Patient convenience and a decrease in the need for telephone communication were the most commonly noted reasons for e-mail use. Facilitators of e-mail use included integration with the electronic medical record, enhanced e-mail access control, security features, and financial compensation. Barriers to e-mail use included privacy and security concerns, concerns about inappropriate e-mail use by patients, and the creation of unrealistic expectations about physician availability. CONCLUSION: E-mail use between academic family physicians and patients was found to be much higher than shown in previous studies of Canadian physicians. This finding might have been owing to unique aspects of academic medicine, remuneration via capitation, or other factors. Efforts to increase physician use of e-mail with patients should address concerns related to privacy and security, electronic medical record integration, and financial compensation.
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Relações Médico-Paciente , Médicos de Família , Comunicação , Correio Eletrônico , Eletrônica , Humanos , Ontário , Inquéritos e QuestionáriosRESUMO
BACKGROUND: There is a pressing need to reduce the burden of chronic disease and improve healthcare system sustainability through improved cancer and chronic disease prevention and screening (CCDPS) in primary care. We aim to create an integrated approach that addresses the needs of the general population and the special concerns of cancer survivors. Building on previous research, we will develop, implement, and test the effectiveness of an approach that proactively targets patients to attend an individualized CCDPS intervention delivered by a Prevention Practitioner (PP). The objective is to determine if patients randomized to receive an individualized PP visit (vs standard care) have improved cancer surveillance and CCDPS outcomes. Implementation frameworks will help identify and address facilitators and barriers to the approach and inform future dissemination and uptake. METHODS/DESIGN: The BETTER WISE project is a pragmatic two-arm cluster randomized controlled trial embedded in a mixed methods design, including a qualitative evaluation and an economic assessment. The intervention, informed by the expanded chronic care model and previous research, will be refined by engaging researchers, practitioners, policy makers, and patients. The BETTER WISE tool kit includes blended care pathways for cancer survivors (breast, colorectal, prostate) and CCDPS including lifestyle risk factors and screening for poverty. Patients aged 40-65, including both cancer survivors and general population patients, will be randomized at the physician level to an intervention group or to a wait-list control group. Once the intervention is completed, patients randomized to wait-list control will be invited to receive a prevention visit. The main outcome, calculated at 12-months follow-up, will be an individual patient-level summary composite index, defined as the proportion of CCDPS actions achieved relative to those for which the patient was eligible at baseline. A qualitative evaluation will capture information related to program outcome, implementation (facilitators and barriers), and sustainability. An economic assessment will examine the projected cost-benefit impact of investing in the BETTER WISE approach. DISCUSSION: This project builds on existing work and engages end users throughout the process to develop, implement, and determine the effectiveness of a multi-faceted intervention that addresses CCDPS and cancer survivorship in primary care settings. TRIAL REGISTRATION: ISRCTN21333761 . Registered on December 19, 2016.
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Doença Crônica/prevenção & controle , Diagnóstico Precoce , Neoplasias/prevenção & controle , Adulto , Sobreviventes de Câncer , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Neoplasias/diagnóstico , Pobreza , Serviços Preventivos de Saúde , Atenção Primária à Saúde , Avaliação de Programas e Projetos de SaúdeRESUMO
Squid, which swim using a coupled fin/jet system powered by muscular hydrostats, pose unique challenges for the study of locomotion. The high flexibility of the fins and complex flow fields generated by distinct propulsion systems require innovative techniques for locomotive assessment. For this study, we used proper orthogonal decomposition (POD) to decouple components of the fin motions and defocusing digital particle tracking velocimetry (DDPTV) to quantify the resultant 3D flow fields. Kinematic footage and DDPTV data were collected from brief squid, Lolliguncula brevis [3.1-6.5â cm dorsal mantle length (DML)], swimming freely in a water tunnel at speeds of 0.39-7.20â DMLâ s-1 Both flap and wave components were present in all fin motions, but the relative importance of the wave components was higher for arms-first swimming than for tail-first swimming and for slower versus higher speed swimming. When prominent wave components were present, more complex interconnected vortex ring wakes were observed, while fin movements dominated by flapping resulted in more spatially separated vortex ring patterns. Although the jet often produced the majority of the thrust for steady rectilinear swimming, our results demonstrated that the fins can contribute more thrust than the jet at times, consistently produce comparable levels of lift to the jet during arms-first swimming, and can boost overall propulsive efficiency. By producing significant drag signatures, the fins can also aid in stabilization and maneuvering. Clearly, fins play multiple roles in squid locomotion, and when coupled with the jet, allow squid to perform a range of swimming behaviors integral to their ecological success.
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Nadadeiras de Animais/fisiologia , Decapodiformes/fisiologia , Locomoção , Animais , Fenômenos Biomecânicos , Cinética , Movimento (Física) , Reologia , NataçãoRESUMO
OBJECTIVE: To determine the number of patient visits, patient demographic information, and diagnoses in an urban ambulatory care setting in a family medicine residency program, and assess the correlation between the number of patient visits and residents' in-training examination (ITE) scores. DESIGN: Retrospective analysis of data from resident practice profiles, electronic medical records, and residents' final ITE scores. SETTING: Family medicine teaching unit in a community hospital in Barrie, Ont. PARTICIPANTS: Practice profile data were from family medicine residents enrolled in the program from July 1, 2013, to June 30, 2014, and electronic medical record and ITE data were from those enrolled in the program from July 1, 2010, to June 30, 2015. MAIN OUTCOME MEASURES: Number of patient visits, patient characteristics (eg, sex, age), priority topics addressed in clinic, resident characteristics (eg, age, sex, level of residency), and residents' final ITE scores. RESULTS: Between July 1, 2013, and June 30, 2014, there were 11 115 patient visits. First-year residents had a mean of 5.48 patient visits per clinic, and second-year residents had a mean of 5.98 patient visits per clinic. A Pearson correlation coefficient of 0.68 was found to exist between the number of patients seen and the final ITE scores, with a 10.5% difference in mean score between residents who had 1251 or more visits and those who had 1150 or fewer visits. Three diagnoses (ie, epistaxis, meningitis, and neck pain) deemed important for Certification by the College of Family Physicians of Canada were not seen by any of the residents in clinic. CONCLUSION: There is a moderate correlation between the number of patients seen by residents in ambulatory care and ITE scores in family medicine. It is important to assess patients' demographic information and diagnoses made in resident practices to ensure an adequate clinical experience.
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Assistência Ambulatorial/estatística & dados numéricos , Avaliação Educacional , Medicina de Família e Comunidade/educação , Internato e Residência/estatística & dados numéricos , Serviços Urbanos de Saúde/estatística & dados numéricos , Adulto , Instituições de Assistência Ambulatorial , Competência Clínica , Feminino , Humanos , Masculino , Ontário , Projetos Piloto , Estudos Retrospectivos , População Urbana/estatística & dados numéricosRESUMO
Although squid are generally considered to be effective predators, little is currently known of how squid maneuver and position themselves during prey strikes. In this study, high-speed video and kinematic analyses were used to study attacks by the brief squid Lolliguncula brevis on both shrimp and fish. Squid attack success was high (>80%) and three behavioral phases were identified: (1) approach, (2) strike and (3) recoil. Lolliguncula brevis demonstrated greater maneuverability (i.e. a smaller length-specific turning radius) and employed more body adjustments (i.e. mantle angle posturing) during approaches toward shrimp versus fish. Squid exhibited higher linear approach/strike velocities and accelerations with faster-swimming fish prey compared with slower shrimp prey. Agility (i.e. turning rate) during prey encounters was comparable to performance extremes observed during non-predatory turns, and did not differ according to prey type or distance. Despite having the ability to modulate tentacle extension velocity, squid instead increased their own swimming velocity rather than increasing tentacle velocity when targeting faster fish prey during the strike phase, but this was not the case for shrimp prey. Irrespective of prey type, L. brevis consistently positioned themselves above the prey target prior to the tentacle strike, possibly to facilitate a more advantageous downward projection of the tentacles. During the recoil, L. brevis demonstrated length-specific turning radii similar to those recorded during the approach despite vigorous escape attempts by some prey. Clearly, turning performance is integral to prey attacks in squid, with differences in attack strategy varying depending on the prey target.
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Cyprinidae/fisiologia , Decapodiformes/fisiologia , Palaemonidae/fisiologia , Comportamento Predatório , Animais , Fenômenos Biomecânicos , NataçãoRESUMO
BACKGROUND: Some etiological factors involved in developmental dysplasia of the hip (DDH) occur in the last trimester of pregnancy, which could result in a decreased incidence of DDH in preterm infants. The aim of this study was to compare the incidence of DDH between preterm and term infants. METHODS: Ultrasound of the hip joint was performed in 2,534 term infants and 376 preterm infants within the population-based Survey of Neonates in Pomerania (SNiP) study. RESULTS: A total of 42 (1.66%) term infants had DDH (Graf type II c, 0.8%; type D, 0.3% left and 0.4% right; type III a, 0.2% left). Eighteen infants had bilateral findings. Hip dysplasia occurred more frequently in female neonates (32/1,182 vs. 10/1,302, p < 0.023; 95% CI 0.012-0.022, χ 2 test). A familial disposition for DDH was found in 169 (6.7%) term infants and 181 (7.1%) infants in the overall population. In preterm infants, dysplasia of the hip was found in only three late preterm infants with gestational age between 36 and 37 weeks (n = 97) and not in preterm infants <36 weeks gestational age (n = 279). Regression analysis revealed a narrowly significant association between gestational week of birth and DDH (relative risk = 1.17; 95% confidence interval 0.99-1.37; p = 0.065). CONCLUSION: Our study suggests that preterm infants <36 weeks gestational age have a decreased risk of DDH.
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Luxação Congênita de Quadril/epidemiologia , Doenças do Prematuro/epidemiologia , Feminino , Alemanha/epidemiologia , Idade Gestacional , Inquéritos Epidemiológicos , Humanos , Incidência , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Gravidez , Estudos Prospectivos , Fatores de Risco , Nascimento a TermoRESUMO
OBJECTIVE: To identify predictors of job satisfaction among academic family medicine faculty members. DESIGN: A comprehensive Web-based survey of all faculty members in an academic department of family medicine. Bivariate and multivariable analyses (logistic regression) were used to identify variables associated with job satisfaction. SETTING: The Department of Family and Community Medicine at the University of Toronto in Ontario and its 15 affiliated community teaching hospitals and community-based teaching practices. PARTICIPANTS: All 1029 faculty members in the Department of Family and Community Medicine were invited to complete the survey. MAIN OUTCOME MEASURES: Faculty members' demographic and practice information; teaching, clinical, administration, and research activities; leadership roles; training needs and preferences; mentorship experiences; health status; stress levels; burnout levels; and job satisfaction. Faculty members' perceptions about supports provided, recognition, communication, retention, workload, teamwork, respect, resource distribution, remuneration, and infrastructure support. Faculty members' job satisfaction, which was the main outcome variable, was obtained from the question, "Overall, how satisfied are you with your job?" RESULTS: Of the 1029 faculty members, 687 (66.8%) responded to the survey. Bivariate analyses revealed 26 predictors as being statistically significantly associated with job satisfaction, including faculty members' ratings of their local department and main practice setting, their ratings of leadership and mentorship experiences, health status variables, and demographic variables. The multivariable analyses identified the following 5 predictors of job satisfaction: the Maslach Burnout Inventory subscales of emotional exhaustion and personal accomplishment; being born in Canada; the overall quality of mentorship that was received being rated as very good or excellent; and teamwork being rated as very good or excellent. CONCLUSION: The findings from this study show that job satisfaction among academic family medicine faculty members is a multi-dimensional construct. Future improvement in overall level of job satisfaction will therefore require multiple strategies.
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Medicina Comunitária , Docentes de Medicina/psicologia , Medicina de Família e Comunidade , Satisfação no Emprego , Logro , Adulto , Idoso , Idoso de 80 Anos ou mais , Esgotamento Profissional/psicologia , Canadá/etnologia , Medicina Comunitária/educação , Comportamento Cooperativo , Medicina de Família e Comunidade/educação , Feminino , Humanos , Liderança , Masculino , Tutoria , Pessoa de Meia-Idade , Inquéritos e Questionários , Equilíbrio Trabalho-VidaRESUMO
Squid rely on multiple sensory systems for predator detection. In this study we examine the role of two sensory systems, the lateral line analogue and vision, in successful predator evasion throughout ontogeny. Squid Doryteuthis pealeii and Lolliguncula brevis were recorded using high-speed videography in the presence of natural predators under light and dark conditions with their lateral line analogue intact or ablated via a pharmacological technique. Paralarval squid showed reduced escape responses when ablated; however, no differences were found between light and dark conditions in non-ablated paralarvae, as was previously shown in juveniles and adults, indicating that the lateral line analogue is integral for predator detection early in life. However, vision does play a role in survival because ablated squid in dark conditions had lower levels of survival than all other treatments. Throughout ontogeny, squid oriented themselves anteriorly towards the oncoming predator, maximizing sensory input to the lateral line analogue system and providing better positioning for tail-first escape jetting, the preferred escape mode. Ablated juveniles and adults had lower response times, escape velocities and peak acceleration than non-ablated individuals, indicating that the lateral line analogue enables squid to respond quicker and with more powerful jets to a predator and maximize escape success. Our findings reveal that the lateral line analogue plays a role in predator detection and successful escape response at the earliest life stages, and continues to contribute to successful evasion by aiding visual cues in juvenile and adult squid.
RESUMO
Although steady swimming has received considerable attention in prior studies, unsteady swimming movements represent a larger portion of many aquatic animals' locomotive repertoire and have not been examined extensively. Squids and cuttlefishes are cephalopods with unique muscular hydrostat-driven, dual-mode propulsive systems involving paired fins and a pulsed jet. These animals exhibit a wide range of swimming behavior, but turning performance has not been examined quantitatively. Brief squid, Lolliguncula brevis, and dwarf cuttlefish, Sepia bandensis, were filmed during turns using high-speed cameras. Kinematic features were tracked, including the length-specific radius of the turn (R/L), a measure of maneuverability, and angular velocity (ω), a measure of agility. Both L. brevis and S. bandensis demonstrated high maneuverability, with (R/L)min values of 3.4×10(-3)±5.9×10(-4) and 1.2×10(-3)±4.7×10(-4) (mean±s.e.m.), respectively, which are the lowest measures of R/L reported for any aquatic taxa. Lolliguncula brevis exhibited higher agility than S. bandensis (ωa,max=725.8 versus 485.0 deg s(-1)), and both cephalopods have intermediate agility when compared with flexible-bodied and rigid-bodied nekton of similar size, reflecting their hybrid body architecture. In L. brevis, jet flows were the principal driver of angular velocity. Asymmetric fin motions played a reduced role, and arm wrapping increased turning performance to varying degrees depending on the species. This study indicates that coordination between the jet and fins is important for turning performance, with L. brevis achieving faster turns than S. bandensis and S. bandensis achieving tighter, more controlled turns than L. brevis.
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Decapodiformes/fisiologia , Sepia/fisiologia , Nadadeiras de Animais/anatomia & histologia , Nadadeiras de Animais/fisiologia , Animais , Fenômenos Biomecânicos , Tamanho Corporal , Decapodiformes/anatomia & histologia , Sepia/anatomia & histologia , NataçãoRESUMO
Squids use a pulsed jet and fin movements to swim both arms-first (forward) and tail-first (backward). Given the complexity of the squid multi-propulsor system, 3D velocimetry techniques are required for the comprehensive study of wake dynamics. Defocusing digital particle tracking velocimetry, a volumetric velocimetry technique, and high-speed videography were used to study arms-first and tail-first swimming of brief squid Lolliguncula brevis over a broad range of speeds [0-10 dorsal mantle lengths (DML) s(-1)] in a swim tunnel. Although there was considerable complexity in the wakes of these multi-propulsor swimmers, 3D vortex rings and their derivatives were prominent reoccurring features during both tail-first and arms-first swimming, with the greatest jet and fin flow complexity occurring at intermediate speeds (1.5-3.0â DMLâ s(-1)). The jet generally produced the majority of thrust during rectilinear swimming, increasing in relative importance with speed, and the fins provided no thrust at speeds >4.5â DMLâ s(-1). For both swimming orientations, the fins sometimes acted as stabilizers, producing negative thrust (drag), and consistently provided lift at low/intermediate speeds (<2.0â DMLâ s(-1)) to counteract negative buoyancy. Propulsive efficiency (η) increased with speed irrespective of swimming orientation, and η for swimming sequences with clear isolated jet vortex rings was significantly greater (η=78.6±7.6%, mean±s.d.) than that for swimming sequences with clear elongated regions of concentrated jet vorticity (η=67.9±19.2%). This study reveals the complexity of 3D vortex wake flows produced by nekton with hydrodynamically distinct propulsors.
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Nadadeiras de Animais/fisiologia , Decapodiformes/fisiologia , Natação , Animais , Fenômenos Biomecânicos , Reologia , Gravação em VídeoRESUMO
BACKGROUND: Healthcare integration is a priority in many countries, yet there remains little direction on how to systematically evaluate this construct to inform further development. The examination of community-based palliative care networks provides an ideal opportunity for the advancement of integration measures, in consideration of how fundamental provider cohesion is to effective care at end of life. AIM: This article presents a variable-oriented analysis from a theory-based case study of a palliative care network to help bridge the knowledge gap in integration measurement. DESIGN: Data from a mixed-methods case study were mapped to a conceptual framework for evaluating integrated palliative care and a visual array depicting the extent of key factors in the represented palliative care network was formulated. SETTING/PARTICIPANTS: The study included data from 21 palliative care network administrators, 86 healthcare professionals, and 111 family caregivers, all from an established palliative care network in Ontario, Canada. RESULTS: The framework used to guide this research proved useful in assessing qualities of integration and functioning in the palliative care network. The resulting visual array of elements illustrates that while this network performed relatively well at the multiple levels considered, room for improvement exists, particularly in terms of interventions that could facilitate the sharing of information. CONCLUSION: This study, along with the other evaluative examples mentioned, represents important initial attempts at empirically and comprehensively examining network-integrated palliative care and healthcare integration in general.
Assuntos
Serviços de Saúde Comunitária/organização & administração , Prestação Integrada de Cuidados de Saúde/organização & administração , Cuidados Paliativos/organização & administração , Qualidade da Assistência à Saúde/organização & administração , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , OntárioRESUMO
OBJECTIVE: To collect information about the types, frequency, importance, and quality of mentorship received among academic family medicine faculty, and to identify variables associated with receiving high-quality mentorship. DESIGN: Web-based survey of all faculty members of an academic department of family medicine. SETTING: The Department of Family and Community Medicine of the University of Toronto in Ontario. PARTICIPANTS: All 1029 faculty members were invited to complete the survey. MAIN OUTCOME MEASURES: Receiving mentorship rated as very good or excellent in 1 or more of 6 content areas relevant to respondents' professional lives, and information about demographic and practice characteristics, faculty ratings of their local departments and main practice settings, teaching activities, professional development, leadership, job satisfaction, and health. Bivariate and multivariate analyses identified variables associated with receiving high-quality mentorship. RESULTS: The response rate was 66.8%. Almost all (95.0%) respondents had received mentorship in several areas, with informal mentorship being the most prevalent mode. Approximately 60% of respondents rated at least 1 area of mentoring as very good or excellent. Multivariate logistic regression identified 5 factors associated with an increased likelihood of rating mentorship quality as very good or excellent: positive perceptions of their local department (odds ratio [OR] = 4.02, 95% CI 2.47 to 6.54, P < .001); positive ratings of practice infrastructure (OR = 1.86, 95% CI 1.23 to 2.80, P = .003); increased frequency of receiving mentorship (OR = 2.78, 95% CI 1.59 to 4.89, P < .001); fewer years in practice (OR = 1.93, 95% CI 1.19 to 3.12, P = .007); and practising in a family practice teaching unit (OR = 1.51, 95% CI 1.01 to 2.27, P = .040). CONCLUSION: With increasing emphasis on distributed education and community-based teachers, family medicine faculties will need to develop strategies to support effective mentorship across a range of settings and career stages.