The COVID-19 pandemic has brought great disruption to health systems worldwide. This affected ongoing clinical research, particularly among those most vulnerable to the pandemic, like dementia ...patients. Fundació ACE is a research center and memory clinic based in Barcelona, Spain, one of the hardest-hit countries.
To describe the ad-hoc strategic plan developed to cope with this crisis and to share its outcomes.
We describe participants' clinical and demographic features. Additionally, we explain our strategic plan aimed at minimizing the impact on clinical trial research activities, which included SARS-CoV-2 RT-PCR and IgG serological tests to all participants and personnel. The outcomes of the plan are described in terms of observed safety events and drop-outs during the study period.
A total of 130 patients were participating in 16 active clinical trials in Fundació ACE when the lockdown was established. During the confinement, we performed 1018 calls to the participants, which led to identify adverse events in 26 and COVID-19 symptoms in 6. A total of 83 patients (64%) could restart on-site visits as early as May 11, 2020. All SARS-CoV-2 RT-PCR diagnostic tests performed before on-site visits were negative and only three IgG serological tests were positive. Throughout the study period, we only observed one drop-out, due to an adverse event unrelated to COVID-19.
The plan implemented by Fundació ACE was able to preserve safety and integrity of ongoing clinical trials. We must use the lessons learned from the pandemic and design crisis-proof protocols for clinical trials.
In this paper, we study (homogeneous) predecessor-following platoons in which the vehicle-to-vehicle (V2V) communications are affected by random packet losses. We model the overall platoon as a ...stochastic hybrid system and analyse its string stability via a small-gain approach. For nonlinear platoons, we illustrate how the different elements of the platoon have an impact on string stability, such as platoon topology and vehicle scheduling. For linear time-invariant platoons, we provide an explicit string stability condition that illustrates the interplay between the channel success probability, transmission rate, and time headway constant. Lastly, we illustrate our results by numerical simulations.
Major geologic and climatic changes during the Quaternary exerted a major role in shaping past and contemporary distribution of genetic diversity and structure of aquatic organisms in southern South ...America. In fact, the northern glacial limit along the Pacific coast, an area of major environmental changes in terms of topography, currents, and water salinity, represents a major biogeographic transition for marine and freshwater species. We used mitochondrial DNA sequences (D-loop) to investigate the consequences of Quaternary glacial cycles over the pattern of genetic diversity and structure of G. maculatus (Pisces: Galaxiidae) along two biogeographical provinces in the Chilean coast. Extreme levels of genetic diversity and strong phylogeographic structure characterize the species suggesting a low amount of influence of the last glacial cycle over its demography. However, we recognized contrasting patterns of genetic diversity and structure between main biogeographical areas here analyzed. Along the Intermediate Area (38 degree -41 degree S) each estuarine population constitutes a different unit. In contrast, Magellanic populations (43 degree -53 degree S) exhibited low levels of genetic differentiation. Contrasting patterns of genetic diversity and structure recorded in the species between the analyzed biogeographic areas are consistent with the marked differences in abiotic factors (i.e., different coastal configurations, Quaternary glacial histories, and oceanographic regimes) and to inherent characteristics of the species (i.e., salt-tolerance, physiology, and reproductive behavior).
Introduction. Monitoring child development includes the promotion of development in the healthy child and the detection of delays and early indicators of disorders that begin in the first five years ...of life through easy-to-use, easy to mark, and low-cost screening tests. Objective. To evaluate the internal reliability and inter-rater reliability of the ASQ-3 in Mexican preschool children. Method. The ASQ-3 was applied to parents and/or teachers of 33 - 60 month old children who attended the Centros de Desarrollo Infantil (Child Development Centers-CENDIS) in the public and private sectors of Mexico City. Results. A total of n = 1052 questionnaires were obtained, grouped into six age groups (33, 36, 42, 48, 54, and 60 months of age) according to the Ages and Stages Questionnaire-3 (ASQ-3). The levels of reliability of the ASQ-3 for each of the age groups were acceptable, with a range of α = .77 to α = .88. Regarding inter-rater reliability (parents vs. teachers), moderate correlation levels were observed. Discussion and conclusion. The results obtained suggest that this is a screening instrument that reliably evaluates the five areas of development that make up the ASQ-3 in pre-school children. This represents an opportunity to continue studying the psychometric characteristics of validity of this instrument in representative samples of Mexican children to optimize the process of early childhood development monitoring.
This research proposes a generic methodology for dimensionality reduction upon time-frequency representations applied to the classification of different types of biosignals. The methodology directly ...deals with the highly redundant and irrelevant data contained in these representations, combining a first stage of irrelevant data removal by variable selection, with a second stage of redundancy reduction using methods based on linear transformations. The study addresses two techniques that provided a similar performance: the first one is based on the selection of a set of the most relevant time-frequency points, whereas the second one selects the most relevant frequency bands. The first methodology needs a lower quantity of components, leading to a lower feature space; but the second improves the capture of the time-varying dynamics of the signal, and therefore provides a more stable performance. In order to evaluate the generalization capabilities of the methodology proposed it has been applied to two types of biosignals with different kinds of non-stationary behaviors: electroencephalographic and phonocardiographic biosignals. Even when these two databases contain samples with different degrees of complexity and a wide variety of characterizing patterns, the results demonstrate a good accuracy for the detection of pathologies, over 98%.The results open the possibility to extrapolate the methodology to the study of other biosignals.PUBLICATION ABSTRACT
How do income shocks affect armed conflict? Theory suggests two opposite effects. If labour is used to appropriate resources violently, higher wages may lower conflict by reducing labour supplied to ...appropriation. This is the opportunity cost effect. Alternatively, a rise in contestable income may increase violence by raising gains from appropriation. This is the rapacity effect. Our article exploits exogenous price shocks in international commodity markets and a rich dataset on civil war in Colombia to assess how different income shocks affect conflict. We examine changes in the price of agricultural goods (which are labour intensive) as well as natural resources (which are not). We focus on Colombia's two largest exports, coffee and oil. We find that a sharp fall in coffee prices during the 1990s lowered wages and increased violence differentially in municipalities cultivating more coffee. This is consistent with the coffee shock inducing an opportunity cost effect. In contrast, a rise in oil prices increased both municipal revenue and violence differentially in the oil region. This is consistent with the oil shock inducing a rapacity effect. We also show that this pattern holds in six other agricultural and natural resource sectors, providing evidence that price shocks affect conflict in different directions depending on the type of the commodity.
Este artículo reporta las actividades biológicas de 1-bencil-1,2,3-triazoles: antibacteriana por el método de microdilución en caldo, antioxidante por el método de inactivación del DPPH ...(2,2-difenil-1-picrilhidrazil)• y la toxicidad en el ensayo de artemia (Artemia salina). El compuesto 1-(1-bencil-1H-1,2,3-triazol-4-il) ciclopentanol (50 µg/mLa 200 µg/mL) presentó inhibición selectiva y moderada contra el crecimiento de Staphylococcus aureus 3, mientras que el mismo efecto se registró para el 3-(1-bencil-1H-1,2,3-triazol-4-il)-1-propanol contra E. coli AO11, E. coli AO15 y Salmonella entérica serovar Typhi. Los compuestos 5g-i mostraron la más alta inactivación del DPPH• Los compuestos sintéticos 1,2,3-triazoles evaluados se clasificaron en el intervalo de moderadamente tóxico a no tóxico. Así, basados en la información publicada actualmente, estos podrían ser una fuente de compuestos con actividades biológicas de importancia para la salud humana.
Resistive switching, a phenomenon in which the resistance of a device can be modified by applying an electric field
, is at the core of emerging technologies such as neuromorphic computing and ...resistive memories
. Among the different types of resistive switching, threshold firing
is one of the most promising, as it may enable the implementation of artificial spiking neurons
. Threshold firing is observed in Mott insulators featuring an insulator-to-metal transition
, which can be triggered by applying an external voltage: the material becomes conducting ('fires') if a threshold voltage is exceeded
. The dynamics of this induced transition have been thoroughly studied, and its underlying mechanism and characteristic time are well documented
. By contrast, there is little knowledge regarding the opposite transition: the process by which the system returns to the insulating state after the voltage is removed. Here we show that Mott nanodevices retain a memory of previous resistive switching events long after the insulating resistance has recovered. We demonstrate that, although the device returns to its insulating state within 50 to 150 nanoseconds, it is possible to re-trigger the insulator-to-metal transition by using subthreshold voltages for a much longer time (up to several milliseconds). We find that the intrinsic metastability of first-order phase transitions is the origin of this phenomenon, and so it is potentially present in all Mott systems. This effect constitutes a new type of volatile memory in Mott-based devices, with potential applications in resistive memories, solid-state frequency discriminators and neuromorphic circuits.
Catalysis is a topic of continuous interest since it was discovered in chemistry centuries ago. Aiming at the advance of reactions for efficient processes, a number of approaches have been developed ...over the last 180 years, and more recently, porphyrins occupy an important role in this field. Porphyrins and metalloporphyrins are fascinating compounds which are involved in a number of synthetic transformations of great interest for industry and academy. The aim of this review is to cover the most recent progress in reactions catalysed by porphyrins in scalable procedures, thus presenting the state of the art in reactions of epoxidation, sulfoxidation, oxidation of alcohols to carbonyl compounds and C-H functionalization. In addition, the use of porphyrins as photocatalysts in continuous flow processes is covered.
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