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1.
HEC Forum ; 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38231425

RESUMO

Organizational ethics-defined as the alignment of an institution's practices with its mission, vision, and values-is a growing field in health care not well characterized in empirical literature. To capture the scope and context of organizational ethics work in United States healthcare institutions, we conducted a nationwide convenience survey of ethicists regarding the scope of organizational ethics work, common challenges faced, and the organizational context in which this work is done. In this article, we report substantial variability in the structure of organizational ethics programs and the settings in which it is conducted. Notable findings included disagreement about the activities that comprise organizational ethics and a lack of common metrics used to assess organizational ethics activities. A frequently cited barrier to full engagement in these activities was poor institution-wide understanding about the role and function of organizational ethics resources. These data suggest a tension in the trajectory of organizational ethics' professionalization: while some variability is appropriate to the field's relative youth, inadequate attention to definitions of organizational ethics practice and metrics for success can impede discussions about appropriate institutional support, leadership context, and training for practitioners.

2.
Camb Q Healthc Ethics ; : 1-4, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36524241

RESUMO

The role of power in healthcare can raise many ethical challenges. Power is ownership, whether given, ceded, or taken of another person's autonomy. When a person has power over someone else, they can control or strongly influence the decision-making freedom of that person. From the principalist perspective1,2 of healthcare ethics, denying a person their freedom to choose should only occur when justifying conditions related to beneficence and nonmaleficence are sufficiently satisfied. In healthcare, it is rare to be able to identify situations where paternalism is justified. However, experience suggests that abusive power in healthcare is used too frequently without justifying criteria.

3.
Ecol Lett ; 24(10): 2282-2297, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34288328

RESUMO

Among-individual variation in vital rates, such as mortality and birth rates, exists in nearly all populations. Recent studies suggest that this individual heterogeneity produces substantial life-history and fitness differences among individuals, which in turn scale up to influence population dynamics. However, our ability to understand the consequences of individual heterogeneity is limited by inconsistencies across conceptual frameworks in the field. Studies of individual heterogeneity remain filled with contradicting and ambiguous terminology that introduces risks of misunderstandings, conflicting models and unreliable conclusions. Here, we synthesise the existing literature into a single and comparatively straightforward framework with explicit terminology and definitions. This work introduces a distinction between potential vital rates and realised vital rates to develop a coherent framework that maps directly onto mathematical models of individual heterogeneity. We suggest the terms "fixed condition" and "dynamic condition" be used to distinguish potential vital rates that are permanent from those that can change throughout an individual's life. To illustrate, we connect the framework to quantitative genetics models and to common classes of statistical models used to infer individual heterogeneity. We also develop a population projection matrix model that provides an example of how our definitions are translated into precise quantitative terms.


Assuntos
Modelos Estatísticos , Modelos Teóricos , Humanos , Dinâmica Populacional
4.
Ecotoxicol Environ Saf ; 220: 112324, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34015630

RESUMO

Insecticides are extensively used worldwide to kill insect pests, yet organisms are most often exposed to insecticides at sublethal concentrations. Our understanding of sublethal effects on life histories is needed to predict the impact of insecticides on population dynamics and improve insecticide use and pest control. Sublethal concentrations can impact life histories directly and indirectly through changes in the intraspecific competition. Yet, few studies have evaluated the sublethal effects on intraspecific competition and these do not disentangle the insecticide effects on interference competition versus exploitative competition. As such, sublethal effects on the relative contribution of each pathways in shaping life histories are largely unknown, despite the fact that this can impact population dynamics. In this study, we focused on the neurotoxic insecticide spinosad and investigated its sublethal effects on interference among the aggressive larvae of the tortrix moth Adoxophyes honmai and the consequences for life histories. We conducted a set of paired experiments to disentangle the insecticide effects on interference from the ones on exploitation. Spinosad was found to amplify interference with most effects on mortality which lets us suggest that the insecticide likely increases the level of aggressive interactions resulting in more conspecific killings (e.g. cannibalism). Spinosad exposure was found to impair movement ability. Less movements may increase susceptibility to conspecific attacks and or increase aggresivity for better defence, two plausible mechanisms that could explain the increase in interference with insecticide. This study shows that insecticide at sublethal concentration can impact life histories by altering the strength of interference competition. Many organisms (pest and non-target species) compete through interference and theory predicts that a change in interference can substantially change dynamics. Our finding therefore reveals the importance of assessing the effect of insecticides on the mechanisms of competition when predicting their impact on populations.


Assuntos
Controle de Insetos , Inseticidas/farmacologia , Macrolídeos/farmacologia , Mariposas/efeitos dos fármacos , Agressão/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/fisiologia , Mariposas/crescimento & desenvolvimento , Mariposas/fisiologia , Movimento/efeitos dos fármacos , Dinâmica Populacional
5.
Health Care Manag (Frederick) ; 39(4): 168-174, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33079768

RESUMO

The success of a health care institution-as defined by delivering high-quality, high-value care, positive patient outcomes, and financial solvency-is inextricably tied to the culture within that organization. The ability to achieve and sustain alignment between its mission, values, and everyday practices defines a positive organizational culture. An institution that has a diminished organizational culture, reflected in the failure to consistently align management and clinical decisions and practices with its mission and values, will struggle. The presence of misalignment or of ethics gaps affects the quality of care being delivered, the morale of the staff, and the organization's image in the community. Transforming an organizational culture will provide a foundation for success and a framework for daily ethics-grounded operations in any organization. However, building an ethics-grounded organization is a challenging process requiring strong organization leadership and planning. Using a case study, the authors provide a multiyear, continuous step-by-step strategy consisting of identifying ethics culture gaps, establishing an ethics taskforce, clarifying and prioritizing the problems, developing strategy for change, implementing the strategy, and evaluating outcomes. This process will assist organizations in aligning its actions with its mission and values, to find success on all fronts.


Assuntos
Ética Institucional , Liderança , Cultura Organizacional , Objetivos Organizacionais , Atenção à Saúde , Humanos , Estudos de Casos Organizacionais
6.
Am Nat ; 190(1): E13-E27, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28617635

RESUMO

Individual differences in genetics, age, or environment can cause tremendous differences in individual life-history traits. This individual heterogeneity generates demographic heterogeneity at the population level, which is predicted to have a strong impact on both ecological and evolutionary dynamics. However, we know surprisingly little about the sources of individual heterogeneity for particular taxa or how different sources scale up to impact ecological and evolutionary dynamics. Here we experimentally study the individual heterogeneity that emerges from both genetic and nongenetic sources in a species of freshwater zooplankton across a large gradient of food quality. Despite the tight control of environment, we still find that the variation from nongenetic sources is greater than that from genetic sources over a wide range of food quality and that this variation has strong positive covariance between growth and reproduction. We evaluate the general consequences of genetic and nongenetic covariance for ecological and evolutionary dynamics theoretically and find that increasing nongenetic variation slows evolution independent of the correlation in heritable life-history traits but that the impact on ecological dynamics depends on both nongenetic and genetic covariance. Our results demonstrate that variation in the relative magnitude of nongenetic versus genetic sources of variation impacts the predicted ecological and evolutionary dynamics.


Assuntos
Evolução Biológica , Daphnia/genética , Ecologia , Animais , Meio Ambiente , Dinâmica Populacional , Reprodução , Zooplâncton
7.
J Healthc Manag ; 62(1): 18-27, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28319986

RESUMO

EXECUTIVE SUMMARY: This study of Pioneer accountable care organizations (ACOs) suggests that the ACO model is creating moral distress for physicians and business leaders in seven critical ways:Despite an overall sense of optimism associated with the ACO model, our research identified an underlying sense of moral distress at most sites. A clear opportunity exists for ACOs to use a more comprehensive, coordinated approach to proactively resolving ethical dilemmas while continuing the march toward risk-based contracts.


Assuntos
Organizações de Assistência Responsáveis/ética , Contratos , Humanos
8.
Health Care Manag (Frederick) ; 36(4): 342-346, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28953578

RESUMO

Health care organizations have embraced the concept of patient-centered care, but there is concern that the mere inclusion of those words in mission and value statements does not equate to implementation at the health care delivery level. Despite initiatives to align the patient-clinician encounter with broader patient-centered values, there have been mixed results, often creating a gap between practice and the organization's stated position. This preliminary study aims to assess the extent to which patient-centered values are reflected in actual patient care. The survey was sent electronically to Dartmouth's Masters in Health Care Delivery Science alumni, leaders in health care management. A majority of 49 survey respondents acknowledged the importance of patient-centered values to their organizations. However, 90% of respondents identified a gap between patient-centered values and day-to-day patient care. Thematic analysis of respondent comments showed a misalignment of organizational incentives with patient-centered care, a lack of leadership priority given to patient-centered values, and a failure to clearly define patient-centered values. Quantitative and qualitative data indicated that patient-centered statements represented rhetoric rather than the reality of patient care. Consistently achieving patient-centered care will require leaders to adopt a systematic approach to move beyond rhetoric.


Assuntos
Administração de Serviços de Saúde/normas , Liderança , Cultura Organizacional , Assistência Centrada no Paciente/organização & administração , Atitude do Pessoal de Saúde , Humanos , Assistência Centrada no Paciente/normas , Inquéritos e Questionários
9.
Clin Infect Dis ; 60(12): 1816-20, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25767254

RESUMO

In 2012, dozens of patients of Exeter Hospital in New Hampshire contracted new hepatitis C infections that were tracked back to a cardiac technician who ultimately confessed to drug diversion. A multistate epidemiological investigation of hepatitis C cases occurring in multiple hospitals revealed that the technician had been fired from prior institutions due to similar drug diversion activity, about which Exeter Hospital had not been notified. In this article, we highlight the institutional ethical issues raised by this outbreak, and propose a national centralized reporting system to support institutional fulfillment of the ethical obligation to protect the health of patients by preventing such nosocomial outbreaks.


Assuntos
Infecção Hospitalar , Notificação de Doenças , Ética Institucional , Hepatite C , Abuso de Substâncias por Via Intravenosa , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/etiologia , Infecção Hospitalar/transmissão , Revelação/ética , Surtos de Doenças/estatística & dados numéricos , Emprego/ética , Hepatite C/epidemiologia , Hepatite C/etiologia , Hepatite C/transmissão , Humanos , New Hampshire
10.
HEC Forum ; 27(2): 157-70, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26013844

RESUMO

The ethical standard for informed consent is fostered within a shared decision-making (SDM) process. SDM has become a recognized and needed approach in health care decision-making. Based on an ethical foundation, the approach fosters the active engagement of patients, where the clinician presents evidence-based treatment information and options and openly elicits the patient's values and preferences. The SDM process is affected by the context in which the information exchange occurs. Rural settings are one context that impacts the delivery of health care and SDM. Rural health care is significantly influenced by economic, geographical and social characteristics. Several specific distinctive features influence rural health care decision-making-poverty, access to health care, isolation, over-lapping relationships, and a shared culture. The rural context creates challenges as well as fosters opportunities for the application of SDM as a natural dynamic within the rural provider-patient relationship. To fulfill the ethical requirements of informed consent through SDM, it is necessary to understand its inherent challenges and opportunities. Therefore, rural clinicians and ethicists need to be cognizant of the impact of the rural setting on SDM and use the insights as an opportunity to achieve SDM.


Assuntos
Tomada de Decisões , Consentimento Livre e Esclarecido/ética , Participação do Paciente/métodos , Atenção Primária à Saúde/métodos , Serviços de Saúde Rural , Feminino , Humanos , Masculino
11.
Ecol Lett ; 17(3): 284-93, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24350974

RESUMO

The interaction between the immune system and pathogens is often characterised as a predator-prey interaction. This characterisation ignores the fact that both require host resources to reproduce. Here, we propose novel theory that considers how these resource requirements can modify the interaction between the immune system and pathogens. We derive a series of models to describe the energetic interaction between the immune system and pathogens, from fully independent resources to direct competition for the same resource. We show that increasing within-host resource supply has qualitatively distinct effects under these different scenarios. In particular, we show the conditions for which pathogen load is expected to increase, decrease or even peak at intermediate resource supply. We survey the empirical literature and find evidence for all three patterns. These patterns are not explained by previous theory, suggesting that competition for host resources can have a strong influence on the outcome of disease.


Assuntos
Metabolismo Energético/imunologia , Interações Hospedeiro-Patógeno/imunologia , Modelos Biológicos , Simulação por Computador , Dinâmica Populacional
12.
Proc Biol Sci ; 281(1792)2014 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-25143034

RESUMO

Parasites often induce life-history changes in their hosts. In many cases, these infection-induced life-history changes are driven by changes in the pattern of energy allocation and utilization within the host. Because these processes will affect both host and parasite fitness, it can be challenging to determine who benefits from them. Determining the causes and consequences of infection-induced life-history changes requires the ability to experimentally manipulate life history and a framework for connecting life history to host and parasite fitness. Here, we combine a novel starvation manipulation with energy budget models to provide new insights into castration and gigantism in the Daphnia magna-Pasteuria ramosa host-parasite system. Our results show that starvation primarily affects investment in reproduction, and increasing starvation stress reduces gigantism and parasite fitness without affecting castration. These results are consistent with an energetic structure where the parasite uses growth energy as a resource. This finding gives us new understanding of the role of castration and gigantism in this system, and how life-history variation will affect infection outcome and epidemiological dynamics. The approach of combining targeted life-history manipulations with energy budget models can be adapted to understand life-history changes in other disease systems.


Assuntos
Daphnia/microbiologia , Daphnia/fisiologia , Interações Hospedeiro-Patógeno/fisiologia , Pasteuria/patogenicidade , Adaptação Fisiológica , Animais , Fenômenos Fisiológicos Bacterianos , Tamanho Corporal , Daphnia/crescimento & desenvolvimento , Feminino , Fertilidade/fisiologia , Inanição
13.
Proc Biol Sci ; 281(1788): 20140633, 2014 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-24966312

RESUMO

Although competing species are expected to exhibit compensatory dynamics (negative temporal covariation), empirical work has demonstrated that competitive communities often exhibit synchronous dynamics (positive temporal covariation). This has led to the suggestion that environmental forcing dominates species dynamics; however, synchronous and compensatory dynamics may appear at different length scales and/or at different times, making it challenging to identify their relative importance. We compiled 58 long-term datasets of zooplankton abundance in north-temperate and sub-tropical lakes and used wavelet analysis to quantify general patterns in the times and scales at which synchronous/compensatory dynamics dominated zooplankton communities in different regions and across the entire dataset. Synchronous dynamics were far more prevalent at all scales and times and were ubiquitous at the annual scale. Although we found compensatory dynamics in approximately 14% of all combinations of time period/scale/lake, there were no consistent scales or time periods during which compensatory dynamics were apparent across different regions. Our results suggest that the processes driving compensatory dynamics may be local in their extent, while those generating synchronous dynamics operate at much larger scales. This highlights an important gap in our understanding of the interaction between environmental and biotic forces that structure communities.


Assuntos
Biota , Crustáceos/fisiologia , Lagos , Zooplâncton/fisiologia , Animais , Europa (Continente) , Modelos Biológicos , América do Norte , Dinâmica Populacional , Estações do Ano , Fatores de Tempo , Análise de Ondaletas
14.
Nature ; 455(7217): 1240-3, 2008 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-18972019

RESUMO

A long-standing issue in ecology is reconciling the apparent stability of many populations with robust predictions of large-amplitude population cycles from general theory on consumer-resource interactions. Even when consumers are decoupled from dynamic resources, large-amplitude cycles can theoretically emerge from delayed feedback processes found in many consumers. Here we show that resource-dependent mortality and a dynamic developmental delay in consumers produces a new type of small-amplitude cycle that coexists with large-amplitude fluctuations in coupled consumer-resource systems. A distinctive characteristic of the small-amplitude cycles is slow juvenile development for consumers, leading to a developmental delay that is longer than the cycle period. By contrast, the period exceeds the delay in large-amplitude cycles. These theoretical predictions may explain previous empirical results on coexisting attractors found in Daphnia-algal systems. To test this, we used bioassay experiments that measure the growth rates of individuals in populations exhibiting each type of cycle. The results were consistent with predictions. Together, the new theory and experiments establish that two very general features of consumers--a resource-dependent juvenile stage duration and resource-dependent mortality--combine to produce small-amplitude resource-consumer cycles. This phenomenon may contribute to the prevalence of small-amplitude fluctuations in many other consumer-resource populations.


Assuntos
Daphnia/fisiologia , Eucariotos/fisiologia , Cadeia Alimentar , Animais , Bioensaio , Daphnia/crescimento & desenvolvimento , Feminino , Modelos Biológicos , Óvulo/fisiologia
15.
Health Care Manag (Frederick) ; 33(2): 158-64, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24776835

RESUMO

The success of a health care institution-as defined by delivering high-quality, high-value care, positive patient outcomes, and financial solvency-is inextricably tied to the culture within that organization. The ability to achieve and sustain alignment between its mission, values, and everyday practices defines a positive organizational culture. An institution that has a diminished organizational culture, reflected in the failure to consistently align management and clinical decisions and practices with its mission and values, will struggle. The presence of misalignment or of ethics gaps affects the quality of care being delivered, the morale of the staff, and the organization's image in the community. Transforming an organizational culture will provide a foundation for success and a framework for daily ethics-grounded operations in any organization. However, building an ethics-grounded organization is a challenging process requiring strong organization leadership and planning. Using a case study, the authors provide a multiyear, continuous step-by-step strategy consisting of identifying ethics culture gaps, establishing an ethics taskforce, clarifying and prioritizing the problems, developing strategy for change, implementing the strategy, and evaluating outcomes. This process will assist organizations in aligning its actions with its mission and values, to find success on all fronts.


Assuntos
Ética Institucional , Ética Médica , Cultura Organizacional , Comitês Consultivos/organização & administração , Ética Institucional/educação , Ética Médica/educação , Administração de Instituições de Saúde/ética , Administração de Instituições de Saúde/métodos , Administração Hospitalar/ética , Administração Hospitalar/métodos , Humanos , Inovação Organizacional , Avaliação de Programas e Projetos de Saúde
16.
Sci Rep ; 13(1): 3528, 2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36864085

RESUMO

Parasitoids are small insects, (e.g., small wasps or flies) that reproduce by laying eggs on or within host arthropods. Parasitoids make up a large proportion of the world's biodiversity and are popular agents of biological control. Idiobiont parasitoids paralyze their hosts upon attack and thus are expected to only target hosts large enough to support offspring development. Host resources generally impact host attributes and life histories including size, development, and life span. Some argue slow host development in response to resource quality increases parasitoid efficacy (i.e., a parasitoid's ability to successfully reproduce on or within a host) due to longer host exposure to parasitoids. However, this hypothesis is not always supported and does not consider variation in other host traits in response to resources that may be important for parasitoids (e.g., variation in host size is known to impact parasitoid efficacy). In this study we test whether trait variation within host developmental stages in response to host resources is more important for parasitoid efficacy and life histories than trait variation across host developmental stages. We exposed seed beetle hosts raised on a food quality gradient to mated female parasitoids and measured the number of hosts parasitized and parasitoid life history traits at the scale of host stage- and age-structure. Our results suggest host food quality does not cascade to impact idiobiont parasitoid life histories despite large food quality effects on host life history. Instead, variation in host life histories across host developmental stages better predicts parasitoid efficacy and life histories, suggesting finding a host in a specific instar is more important for idiobiont parasitoids than finding hosts on or within higher quality resources.


Assuntos
Artrópodes , Besouros , Feminino , Animais , Humanos , Biodiversidade , Desenvolvimento Infantil , Qualidade dos Alimentos
17.
Pest Manag Sci ; 79(7): 2581-2590, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36869740

RESUMO

BACKGROUND: Tebufenozide is widely used to control populations of the smaller tea tortrix, Adoxophyes honmai. However, A. honmai has evolved resistance such that straightforward pesticide application is an untenable long-term approach for population control. Evaluating the fitness cost of resistance is key to devising a management strategy that slows the evolution of resistance. RESULTS: We used three approaches to assess the life-history cost of tebufenozide resistance with two strains of A. honmai: a tebufenozide-resistant strain recently collected from the field in Japan and a susceptible strain that has been maintained in the laboratory for decades. First, we found that the resistant strain with standing genetic variation did not decline in resistance in the absence of insecticide over four generations. Second, we found that genetic lines that spanned a range of resistance profiles did not show a negative correlation between their LD50 , the dosage at which 50 % of individuals died, and life-history traits that are correlates of fitness. Third, we found that the resistant strain did not manifest life-history costs under food limitation. Our crossing experiments indicate that the allele at an ecdysone receptor locus known to confer resistance explained much of the variance in resistance profiles across genetic lines. CONCLUSION: Our results indicate that the point mutation in the ecdysone receptor, which is widespread in tea plantations in Japan, does not carry a fitness cost in the tested laboratory conditions. The absence of a cost of resistance and the mode of inheritance have implications for which strategies may be effective in future resistance management efforts. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Inseticidas , Mariposas , Animais , Mariposas/genética , Hidrazinas , Inseticidas/farmacologia , Chá , Resistência a Inseticidas/genética
18.
Am Nat ; 179(1): 95-109, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22173463

RESUMO

Population cycles have fascinated ecologists since the early nineteenth century, and the dynamics of insect populations have been central to understanding the intrinsic and extrinsic biological processes responsible for these cycles. We analyzed an extraordinary long-term data set (every 5 days for 48 years) of a tea tortrix moth (Adoxophyes honmai) that exhibits two dominant cycles: an annual cycle with a conspicuous pattern of four or five single-generation cycles superimposed on it. General theory offers several candidate mechanisms for generation cycles. To evaluate these, we construct and parameterize a series of temperature-dependent, stage-structured models that include intraspecific competition, parasitism, mate-finding Allee effects, and adult senescence, all in the context of a seasonal environment. By comparing the observed dynamics with predictions from the models, we find that even weak larval competition in the presence of seasonal temperature forcing predicts the two cycles accurately. None of the other mechanisms predicts the dynamics. Detailed dissection of the results shows that a short reproductive life span and differential winter mortality among stages are the additional life-cycle characteristics that permit the sustained cycles. Our general modeling approach is applicable to a wide range of organisms with temperature-dependent life histories and is likely to prove particularly useful in temperate systems where insect pest outbreaks are both density and temperature dependent.


Assuntos
Modelos Biológicos , Mariposas/fisiologia , Animais , Comportamento Competitivo , Japão , Larva/crescimento & desenvolvimento , Larva/fisiologia , Mariposas/crescimento & desenvolvimento , Dinâmica Populacional , Reprodução , Estações do Ano , Temperatura , Análise de Ondaletas
19.
J Exp Biol ; 215(Pt 15): 2684-95, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22786646

RESUMO

Retinal neurogenesis in fish facilitates cellular rearrangement throughout ontogeny, potentially allowing for optimization of the visual system to shifts in habitat and behaviour. To test this possibility, we studied the developmental trajectory of the photopic visual process in the Nile tilapia. We examined ontogenetic changes in lens transmission, photoreceptor sensitivity and post-receptoral sensitivity, and used these to estimate changes in cone pigment frequency and retinal circuitry. We observed an ontogenetic decrease in ultraviolet (UV) photoreceptor sensitivity, which resulted from a reduction in the SWS1 cone pigment frequency, and was associated with a reduction in lens transmission at UV wavelengths. Additionally, post-receptoral sensitivity to both UV and long wavelengths decreased with age, probably reflecting changes in photoreceptor sensitivity and retinal circuitry. This novel remodelling of retinal circuitry occurred following maturation of the visual system but prior to reaching adulthood, and thus may facilitate optimization of the visual system to the changing sensory demands. Interestingly, the changes in post-receptoral sensitivity to long wavelengths could not be predicted by the changes observed in lens transmission, cone pigment frequency or photoreceptor sensitivity. This finding emphasizes the importance of considering knowledge of visual sensitivity and retinal processing when studying visual adaptations and attempting to relate visual function to the natural environment. This study advances our understanding of ontogeny in visual systems and demonstrates that the association between different elements of the visual process can be explored effectively by examining visual function throughout ontogeny.


Assuntos
Ciclídeos/crescimento & desenvolvimento , Olho/crescimento & desenvolvimento , Envelhecimento/fisiologia , Animais , Peso Corporal/fisiologia , Eletrorretinografia , Olho/efeitos da radiação , Cristalino/crescimento & desenvolvimento , Cristalino/efeitos da radiação , Luz , Pigmentação/fisiologia , Pigmentação/efeitos da radiação , Células Fotorreceptoras Retinianas Cones/fisiologia , Células Fotorreceptoras Retinianas Cones/efeitos da radiação
20.
Jt Comm J Qual Patient Saf ; 38(3): 99-102, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22435226

RESUMO

We find the PE approach as part of the VA's IE program an excellent model from which all can learn. We have offered some additional issues for consideration on the basis of our own work and that of others. We hope that the combination of those ideas and the work of Foglia et al. will further advance the promotion and adoption of PE as a means to improve quality and minimize the occurrence of potentially harmful ethics conflicts.


Assuntos
Atenção à Saúde/ética , Ética Clínica , Ética Institucional , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Melhoria de Qualidade/organização & administração , Humanos
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