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1.
iScience ; 27(3): 109036, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38361612

RESUMEN

Among the most important impacts of biological invasions on biodiversity is biotic homogenization, which may further compromise key ecosystem processes. However, the extent to which they homogenize functional diversity and shift dominant ecological strategies of invaded communities remains uncertain. Here, we investigated changes in plant communities in a northern North American forest in response to invasive earthworms, by examining the taxonomic and functional diversity of the plant community and soil ecosystem functions. We found that although plant taxonomic diversity did not change in response to invasive earthworms, they modified the dominance structure of plant functional groups. Invasive earthworms promoted the dominance of fast-growing plants at the expense of slow-growing ones. Moreover, earthworms decreased plant functional diversity, which coincided with changes in abiotic and biotic soil properties. Our study reveals that invasive earthworms erode multiple biodiversity facets of invaded forests, with potential cascading effects on ecosystem functioning.

2.
PLOS Glob Public Health ; 2(12): e0001361, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36962919

RESUMEN

Despite tremendous efforts in fighting HIV over the last decades, the estimated annual number of new infections is still a staggering 1.5 million. There is evidence that voluntary medical male circumcision (VMMC) provides protection against men's heterosexual acquisition of HIV-1 infection. Despite good progress, most countries implementing VMMC for HIV prevention programmes are challenged to reach VMMC coverage rates of 90%. Particularly for men older than 25 years, a low uptake has been reported. Consequently, there is a need to identify, study and implement interventions that could increase the uptake of VMMC. Loss of income and incurred transportation costs have been reported as major barriers to uptake of VMMC. In response, it has been suggested to use economic compensation in order to increase VMMC uptake. In this discussion paper, we present and review relevant arguments and concerns to inform decision-makers about the ethical implications of using economic compensation, and to provide a comprehensive basis for policy and project-related discussions and decisions.

3.
J Med Ethics ; 2021 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-33789948

RESUMEN

In 2016, following pandemic influenza threats and the 2014-2016 Ebola virus disease outbreaks, the WHO developed a guidance document for managing ethical issues in infectious disease outbreaks. In this article, we analyse some ethical issues that have had a predominant role in decision making in response to the current COVID-19 pandemic but were absent or not addressed in the same ways in the 2016 guidance document. A pandemic results in a health crisis and social and political crises both nationally and globally. The ethical implications of these global effects should be properly identified so that appropriate actions can be taken globally and not just in national isolation. Our analysis, which is a starting point to test the broader relevance of the 2016 WHO document that remains the only available guidance document applicable globally, concludes that the WHO guidance should be updated to provide reasoned and thoughtful comprehensive ethics advice for the sound management of the current and future pandemics.

4.
Bull World Health Organ ; 99(2): 138-147, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33551507

RESUMEN

OBJECTIVE: To assess the current state of national ethics committees and the challenges they face. METHODS: We surveyed national ethics committees between 30 January and 21 February 2018. FINDINGS: In total, representatives of 87 of 146 national ethics committees (59.6%) participated. The 84 countries covered were in all World Bank income categories and all World Health Organization regions. Many national ethics committees lack resources and face challenges in several domains, like independence, funding or efficacy. Only 40.2% (35/87) of committees expressed no concerns about independence. Almost a quarter (21/87) of committees did not make any ethics recommendations to their governments in 2017, and the median number of reports, opinions or recommendations issued was only two per committee Seventy-two (82.7%) national ethics committees included a philosopher or a bioethicist. CONCLUSION: National ethics (or bioethics) committees provide recommendations and guidance to governments and the public, thereby ensuring that public policies are informed by ethical concerns. Although the task is seemingly straightforward, implementation reveals numerous difficulties. Particularly in times of great uncertainty, such as during the current coronavirus disease 2019 pandemic, governments would be well advised to base their actions not only on technical considerations but also on the ethical guidance provided by a national ethics committee. We found that, if the advice of national ethics committees is to matter, they must be legally mandated, independent, diverse in membership, transparent and sufficiently funded to be effective and visible.


Asunto(s)
Bioética , Comités de Ética/organización & administración , Encuestas y Cuestionarios , Estudios Transversales , Gobierno , Humanos , Internacionalidad
5.
Annu Rev Control ; 51: 525-539, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33362428

RESUMEN

We investigate adaptive strategies to robustly and optimally control the COVID-19 pandemic via social distancing measures based on the example of Germany. Our goal is to minimize the number of fatalities over the course of two years without inducing excessive social costs. We consider a tailored model of the German COVID-19 outbreak with different parameter sets to design and validate our approach. Our analysis reveals that an open-loop optimal control policy can significantly decrease the number of fatalities when compared to simpler policies under the assumption of exact model knowledge. In a more realistic scenario with uncertain data and model mismatch, a feedback strategy that updates the policy weekly using model predictive control (MPC) leads to a reliable performance, even when applied to a validation model with deviant parameters. On top of that, we propose a robust MPC-based feedback policy using interval arithmetic that adapts the social distancing measures cautiously and safely, thus leading to a minimum number of fatalities even if measurements are inaccurate and the infection rates cannot be precisely specified by social distancing. Our theoretical findings support various recent studies by showing that (1) adaptive feedback strategies are required to reliably contain the COVID-19 outbreak, (2) well-designed policies can significantly reduce the number of fatalities compared to simpler ones while keeping the amount of social distancing measures on the same level, and (3) imposing stronger social distancing measures early on is more effective and cheaper in the long run than opening up too soon and restoring stricter measures at a later time.

7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4775-4778, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-33019058

RESUMEN

The performance and safety of human robot interaction (HRI) can be improved by using subject-specific movement prediction. Typical models include biomechanical (parametric) or black-box (non-parametric) models. The current work aims to investigate the benefits and drawbacks of these approaches by comparing elbow-joint torque predictions based on electromyography signals of the elbow flexors and extensors. To this end, a parameterized biomechanical model is compared to a non-parametric (Gaussian-process) approach. Both models showed adequate results in predicting the elbow-joint torques. While the non-parametric model requires minimal modeling effort, the parameterized biomechanical model can lead to deeper insight of the underlying subject specific musculoskeletal system.


Asunto(s)
Articulación del Codo , Movimiento , Codo , Electromiografía , Humanos , Torque
8.
BMC Med Ethics ; 20(1): 29, 2019 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-31060618

RESUMEN

BACKGROUND: Ensuring that countries have adequate research capacities is essential for an effective and efficient response to infectious disease outbreaks. The need for ethical principles and values embodied in international research ethics guidelines to be upheld during public health emergencies is widely recognized. Public health officials, researchers and other concerned stakeholders also have to carefully balance time and resources allocated to immediate treatment and control activities, with an approach that integrates research as part of the outbreak response. Under such circumstances, research "ethics preparedness" constitutes an important foundation for an effective response to infectious disease outbreaks and other health emergencies. MAIN TEXT: A two-day workshop was convened in March 2018 by the World Health Organisation Global Health Ethics Team and the African coaLition for Epidemic Research, Response and Training, with representatives of National Ethics Committees, to identify practical processes and procedures related to ethics review preparedness. The workshop considered five areas where work might be undertaken to facilitate rapid and sound ethics review: preparing national ethics committees for outbreak response; pre-review of protocols; multi-country review; coordination between national ethics committees and other key stakeholders; data and benefit sharing; and export of samples to third countries. In this paper, we present the recommendations that resulted from the workshop. In particular, the participants recommended that Ethics Committees would develop a formal national standard operating procedure for emergency response ethical review; that there is a need to clarify the terminology and expectations of pre-review of generic protocols and agree upon specific terminology; that there is a need to explore mechanisms for multi-country emergency ethical consultation, and to establish procedures for communication between national ethics committees and other oversight bodies and public health authorities. In addition, it was suggested that ethics committees should request from researchers, at a minimum, a preliminary data sharing and sample sharing plan that outlines the benefit to the population from which data and samples are to be drawn. This should be followed in due time by a full plan. CONCLUSION: It is hoped that the national ethics committees, supported by the WHO, relevant collaborative research consortia and external funding agencies, will work towards bringing these recommendations into practice, for supporting the conduct of effective research during outbreaks.


Asunto(s)
Planificación en Desastres , Brotes de Enfermedades/ética , Revisión Ética , Brotes de Enfermedades/prevención & control , Educación , Comités de Ética Clínica , Comités de Ética en Investigación , Humanos
12.
J Neurosci ; 35(10): 4131-9, 2015 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-25762660

RESUMEN

Parvalbumin (PV)-expressing perisoma-inhibiting interneurons (PIIs) of the dentate gyrus integrate rapidly correlated synaptic inputs and generate short-duration action potentials that propagate along the axon to their output synapses, supporting fast inhibitory signaling onto their target cells. Here we show that PV-PIIs in rat and mouse dentate gyrus (DG) integrate their intrinsic activity over time and can turn into a persistent firing mode characterized by the ability to generate long-lasting trains of action potentials at ∼50 Hz in the absence of additional inputs. Persistent firing emerges in the axons remote from the axon initial segment and markedly depends on hyperpolarization-activated cyclic nucleotide-gated channel (HCNC) activation. Persistent firing properties are modulated by intracellular Ca(2+) levels and somatic membrane potential. Detailed computational single-cell PIIs models reveal that HCNC-mediated conductances can contribute to persistent firing during conditions of a shift in their voltage activation curve to more depolarized potentials. Paired recordings from PIIs and their target granule cells show that persistent firing supports strong inhibitory output signaling. Thus, persistent firing may emerge during conditions of intense activation of the network, thereby providing silencing to the circuitry and the maintenance of sparse activity in the dentate gyrus.


Asunto(s)
Potenciales de Acción/fisiología , Giro Dentado/citología , Canales Regulados por Nucleótidos Cíclicos Activados por Hiperpolarización/metabolismo , Interneuronas/fisiología , Potenciales de Acción/efectos de los fármacos , Animales , Animales Recién Nacidos , Benzazepinas/farmacología , Cardiotónicos/farmacología , Canales Regulados por Nucleótidos Cíclicos Activados por Hiperpolarización/antagonistas & inhibidores , Técnicas In Vitro , Ivabradina , Ratones , Ratones Transgénicos , Microscopía Confocal , Modelos Neurológicos , Red Nerviosa/efectos de los fármacos , Red Nerviosa/fisiología , Parvalbúminas/genética , Parvalbúminas/metabolismo , Vía Perforante/fisiología , Pirimidinas/farmacología , Ratas , Ratas Wistar , Potenciales Sinápticos/efectos de los fármacos , Potenciales Sinápticos/genética , Transfección
13.
Zootaxa ; 3915(1): 111-22, 2015 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-25662113

RESUMEN

The examination of the holotype of Anolis marsupialis Taylor 1956 along with recently collected specimens reveals that A. marsupialis is a valid species. It differs from its closest congeners A. humilis Peters 1863 and A. quaggulus Cope 1885, in male dewlap coloration, scalation, body size, and hemipenial morphology. These findings are supported by preliminary molecular genetic analysis. 


Asunto(s)
Lagartos/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Costa Rica , Ecosistema , Femenino , Lagartos/anatomía & histología , Lagartos/genética , Lagartos/crecimiento & desarrollo , Masculino , Tamaño de los Órganos , Filogenia
14.
Glob Health Action ; 7: 22656, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24560253

RESUMEN

BACKGROUND: Refractive error is defined as the inability of the eye to bring parallel rays of light into focus on the retina, resulting in nearsightedness (myopia), farsightedness (Hyperopia) or astigmatism. Uncorrected refractive error in children is associated with increased morbidity and reduced educational opportunities. Vision screening (VS) is a method for identifying children with visual impairment or eye conditions likely to lead to visual impairment. OBJECTIVE: To analyze the utility of vision screening conducted by teachers and to contribute to a better estimation of the prevalence of childhood refractive errors in Apurimac, Peru. Design : A pilot vision screening program in preschool (Group I) and elementary school children (Group II) was conducted with the participation of 26 trained teachers. Children whose visual acuity was<6/9 [20/30] (Group I) and ≤ 6/9 (Group II) in one or both eyes, measured with the Snellen Tumbling E chart at 6 m, were referred for a comprehensive eye exam. Specificity and positive predictive value to detect refractive error were calculated against clinical examination. Program assessment with participants was conducted to evaluate outcomes and procedures. RESULTS: A total sample of 364 children aged 3-11 were screened; 45 children were examined at Centro Oftalmológico Monseñor Enrique Pelach (COMEP) Eye Hospital. Prevalence of refractive error was 6.2% (Group I) and 6.9% (Group II); specificity of teacher vision screening was 95.8% and 93.0%, while positive predictive value was 59.1% and 47.8% for each group, respectively. Aspects highlighted to improve the program included extending training, increasing parental involvement, and helping referred children to attend the hospital. CONCLUSION: Prevalence of refractive error in children is significant in the region. Vision screening performed by trained teachers is a valid intervention for early detection of refractive error, including screening of preschool children. Program sustainability and improvements in education and quality of life resulting from childhood vision screening require further research.


Asunto(s)
Errores de Refracción/prevención & control , Servicios de Salud Escolar , Selección Visual/métodos , Niño , Preescolar , Femenino , Humanos , Masculino , Perú/epidemiología , Proyectos Piloto , Refracción Ocular , Errores de Refracción/diagnóstico , Errores de Refracción/epidemiología , Agudeza Visual
15.
J Interv Card Electrophysiol ; 32(3): 227-32, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21993595

RESUMEN

Epidemiological studies show that atrial fibrillation (AF) is associated with a doubling of mortality, even after adjustment for confounders. AF can be asymptomatic, but this does not decrease the thromboembolic risk of the patient. Office ECGs, occasional 24-h Holter recordings and long-term ECG event recording might not be sensitive and accurate enough in patients with AF, especially in those with paroxysmal episodes. In one study, 7 days of continuous monitoring with event recorders detected paroxysmal AF in 20 of 65 patients with a previous negative 24-h Holter recording. Over the last decade, enormous improvements have been made in the technology of implantable devices, which can now store significant information regarding heart rhythm. The first subcutaneous implantable monitor (Reveal XT, Medtronic) was validated for continuous AF monitoring by the XPECT study. The dedicated AF detection algorithm uses irregularity and incoherence of R-R intervals to identify and classify patterns in ventricular conduction. Its sensitivity in identifying patients with AF is >96%. Numerous clinical data from continuous monitoring of AF have recently been published. The first applications of this technology have been in the field of surgical and catheter AF ablation. With regard to cryptogenic stroke, an international randomized trial is ongoing to compare standard care with standard care plus the implantable cardiac monitor for AF detection in patients discharged with the diagnosis of cryptogenic stroke: the Crystal AF trial. Continuous AF monitoring provides an optimal picture of daily AF burden, both symptomatic and asymptomatic. Implantable cardiac monitors have high sensitivity, enable better assessment of therapy success and may guide further AF therapy.


Asunto(s)
Fibrilación Atrial/diagnóstico , Fibrilación Atrial/terapia , Ensayos Clínicos como Asunto , Electrocardiografía Ambulatoria/métodos , Almacenamiento y Recuperación de la Información/métodos , Telemedicina/métodos , Terapia Combinada , Humanos
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