Para lograr los beneficios de iluminar con luz natural espacios de trabajo, hay que evitar que la luz natural sea bloqueada por el potencial riesgo de deslumbramiento. Para lograr una adecuada ...caracterización del mismo es importante considerar la percepción del tiempo de exposición de la fuente en el campo de visión (Aspecto no incluido en los modelos de deslumbramiento). Para determinar de qué manera influye este aspecto perceptual en la sensación de deslumbramiento se evaluaron dos escenarios con dos tipos de manchas solares sobre el puesto de trabajo: 1) Con mayor profundidad de ingreso y más tiempo en el campo de visión, 2) Con menor profundidad de ingreso y menos tiempo en el campo de visión. Se midieron parámetros subjetivos (GSV) y variables fotométricas (DGP, EV y CL). Siendo la principal variable explicativa la EV (rho=0.51). Observándose también una mayor tolerancia al deslumbramiento por el efecto transitorio de la fuente.
Nucleophosmin (NPM, also known as B23, numatrin or NO38) is a ubiquitously expressed phosphoprotein belonging to the nucleoplasmin family of chaperones. NPM is mainly localized in the nucleolus where ...it exerts many of its functions, but a proportion of the protein continuously shuttles between the nucleus and the cytoplasm. A growing number of cellular proteins have been described as physical interactors of NPM, and consequently, NPM is thought to have a relevant role in diverse cellular functions, including ribosome biogenesis, centrosome duplication, DNA repair and response to stress. NPM has been implicated in the pathogenesis of several human malignancies and intriguingly, it has been described both as an activating oncogene and a tumor suppressor, depending on cell type and protein levels. In fact, increased NPM expression is associated with different types of solid tumors whereas an impairment of NPM function is characteristic of a subgroup of hematolologic malignancies. A large body of experimental evidence links the deregulation of specific NPM functions to cellular transformation, yet the molecular mechanisms through which NPM contributes to tumorigenesis remain elusive. In this review, we have summarized current knowledge concerning NPM functions, and attempted to interpret its multifaceted and sometimes apparently contradictory activities in the context of both normal cellular homeostasis and neoplastic transformation.
•General overview of exergy-based methods for system analysis is presented.•Taxonomy for exergy-based methods classification is proposed.•Theoretical foundations and details of Extended Exergy ...Accounting are described.
This paper presents a theoretical reassessment of the Extended Exergy Accounting method (EEA in the following), a comprehensive exergy-based analytical paradigm for the evaluation of the total equivalent primary resource consumption in a generic system.
Our intent in this paper was to rigorously review the EEA theory and to highlight its double “valence” as a resource quantifier and to clarify its operative potential. On the one side, EEA can be properly regarded as a general “costing” theory based on a proper knowledge of the cumulative exergy consumption of different supply chains, economic systems and labour market: it is indeed the only method that translates externalities (capital, labour and environmental remediation) into cumulative exergetic costs and thus allows for their rigorous inclusion in a comprehensive resource cost assessment. Indeed, the extended exergy cost eec reflects both the thermodynamic “efficiency” of the production chain and the “hidden” resource costs for the society as a whole.
From another, perhaps even more innovative, perspective, EEA can be viewed as a space and time dependent methodology since economic and labour costs can only be included in the Extended Exergy balance via their exergy equivalents (via two rigorously defined postulates). Since the equivalent exergy cost of the externalities depends both on the type of society and on the time window of the analysis, the extended exergy cost eec reflects in a very real sense both the thermodynamic “efficiency” of the machinery and the “conversion efficiency” of the specific society within which the analysis is performed.
We argue that these two intrinsic features of the EEA method provide both additional insight in and more relevant information for every comparative analysis of energy conversion systems, both at a global and a local level.
In the paper, traditional and advanced exergy analysis methods are briefly discussed and EEA theoretical foundations and details for its application are described in detail.
The method converts not only material and energy flows, but externalities as well (labour, capital and environmental costs) into flows of equivalent primary exergy, so that all exchanges between the system and the environment can be completely accounted for on a rigorous thermodynamic basis.
The current emphasis decision makers and by public opinion alike seem to be placing on sustainability generates the need for continue research in the field of systems analysis, and a preliminary review confirms that exergy may constitute a coherent and rational basis for developing global and local analysis methods. Moreover, extended exergy accounting possesses some specific and peculiar characteristics that make it more suitable for life-cycle and cradle-to-grave (or well-to-wheel) applications.
Taxonomy for the classification of exergy-based methods is proposed.
A novel assessment of the EEA method is provided, its advantages and drawbacks are discussed and areas in need of further theoretical investigation are identified.
Since EEA is a life-cycle method, it is argued that it represents an improvement with regard to other current methods, in that it provides additional insight into the phenomenological aspects of any “energy conversion chain”. The paper demonstrates that the Extended Exergy cost function can be used within the traditional and very well formalized Thermoeconomic framework, replacing the economic cost function in order to evaluate and optimize the consumption of resources of a system in a more complete and rational way.
This paper contains some specific proposals as to the further development of the EEA method, to increase its effectiveness and to improve its practical applicability for system analysis. Suggestions are made on how to include an EEA discussion in the current debate about sustainable development.
•We model feedbacks via density-dependent growth rate and diffusion coefficients.•We show their impact on population conservation in a finite habitat.•Survival can be very sensitive to the introduced ...population size.•Larger habitats are not always better.•Results provide insights for conservation and reintroduction biology.
A key issue in ecology is whether a population will survive long term or go extinct. This is the question we address in this paper for a population in a bounded habitat. We will restrict our study to the case of a single species in a one-dimensional habitat of length L. The evolution of the population density distribution ρ(x, t), where x is the position and t the time, is governed by elementary processes such as growth and dispersal, which, in standard models, are typically described by a constant per capita growth rate and normal diffusion, respectively. However, feedbacks in the regulatory mechanisms and external factors can produce density-dependent rates. Therefore, we consider a generalization of the standard evolution equation, which, after dimensional scaling and assuming large carrying capacity, becomes ∂tρ=∂x(ρν−1∂xρ)+ρμ, where μ,ν∈R. This equation is complemented by absorbing boundaries, mimicking adverse conditions outside the habitat. For this nonlinear problem, we obtain, analytically, exact expressions of the critical habitat size Lc for population survival, as a function of the exponents and initial conditions. We find that depending on the values of the exponents (ν, μ), population survival can occur for either L ≥ Lc, L ≤ Lc or for any L. This generalizes the usual statement that Lc represents the minimum habitat size. In addition, nonlinearities introduce dependence on the initial conditions, affecting Lc.
Abstract
Retinal dystrophies such as
Retinitis pigmentosa
are among the most prevalent causes of inherited legal blindness, for which treatments are in demand. Retinal prostheses have been developed ...to stimulate the inner retinal network that, initially spared by degeneration, deteriorates in the late stages of the disease. We recently reported that conjugated polymer nanoparticles persistently rescue visual activities after a single subretinal injection in the Royal College of Surgeons rat model of
Retinitis pigmentosa
. Here we demonstrate that conjugated polymer nanoparticles can reinstate physiological signals at the cortical level and visually driven activities when microinjected in 10-months-old Royal College of Surgeons rats bearing fully light-insensitive retinas. The extent of visual restoration positively correlates with the nanoparticle density and hybrid contacts with second-order retinal neurons. The results establish the functional role of organic photovoltaic nanoparticles in restoring visual activities in fully degenerate retinas with intense inner retina rewiring, a stage of the disease in which patients are subjected to prosthetic interventions.
Abstract It is widely recognized that Pt nanostructures exhibit favorable catalytic properties for several important technological reactions. Furthermore, selecting an appropriate support has the ...potential to enhance the catalytic activity of these materials. In this study, we investigate Pt nanoparticles deposited on quantum dots using quantum chemical calculations. We explore the utilization of low-dimensional carbonaceous support by employing graphene quantum dots (GQDs), which offer abundant active sites, such as edges, and diverse conformations. This provides excellent tuning possibilities for both chemical and physical properties. Our goal is to gather information on the alterations in electronic properties, charge redistribution and reactivity of platinum particles on GQD, also analyzing their potential role as catalysts in the water dissociation reaction. Based on thermodynamic and kinetic considerations, our calculations suggest that a Pt 3 nanoparticle adsorbed on the edge of the GQD exhibits favorable energetics, leading to a promising catalytic material.
The COVID-19 pandemic is currently a severe challenge for healthcare workers, with a considerable impact on their mental health. In order to focus preventive and rehabilitation measures it's ...fundamental to identify risk factors of such psychological impairment. We designed an observational longitudinal study to systematically examine the psychological wellbeing of all employees in a large University Hospital in Italy, using validated psychometric scales in the context of the occupational physician's health surveillance, in collaboration with Psychiatric Unit.
The study started after ethical approval in August 2020. For each worker, the psychological wellbeing is screened in two steps. The first level questionnaire collects sociodemographic characteristics, personal and occupational COVID-19 exposure, worries and concerns about COVID-19, general psychological discomfort (GHQ-12), post-traumatic stress symptoms (IES-R) and anxiety (GAD-7). Workers who score above the cut-off in at least one scale are further investigated by the second level questionnaire composed by PHQ-9, DES-II and SCL-90. If second level shows psychological impairments, we offer individual specialist treatment (third level). We plan to follow-up all subjects to monitor symptoms and possible chronicization; we aim to investigate potential risk factors through univariate analysis and multivariate logistic regressions.
Preliminary results refer to a sample of 550 workers who completed the multi-step evaluation from August to December 2020, before vaccination campaign started. The participation rate was 90%. At first level screening, 39% of the subjects expressed general psychological discomfort (GHQ-12), 22% post-traumatic stress symptoms (IES-R), and 21% symptoms of anxiety (GAD-7). Women, nurses, younger workers, subjects with COVID-19 working exposure and with an infected family member showed significantly higher psychological impairment compared to colleagues. After the second level screening, 12% and 7% of all workers showed, respectively, depressive and dissociative symptoms; scorings were significantly associated with gender and occupational role. We are currently extending sample size and evaluating subjects over a period of further 12 months.
The possibility to perform a systematic follow-up of psychological wellbeing of all hospital workers, directly or indirectly exposed to pandemic consequences, constitutes a unique condition to detect individual, occupational, and non-occupational risk factors for psychological impairment in situations of prolonged stress, as well as variables associated with symptoms chronicization.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Chronic neuropsychological sequelae following SARS-CoV-2 infection, including depression, anxiety, fatigue, and general cognitive difficulties, are a major public health concern. Given the potential ...impact of long-term neuropsychological impairment, it is important to characterize the frequency and predictors of this post-infection phenotype.
The Epidemiology, Immunology, and Clinical Characteristics of Emerging Infectious Diseases with Pandemic Potential (EPICC) study is a longitudinal study assessing the impact of SARS-CoV-2 infection in U.S. Military Healthcare System (MHS) beneficiaries, i.e. those eligible for care in the MHS including active duty servicemembers, dependents, and retirees. Four broad areas of neuropsychological symptoms were assessed cross-sectionally among subjects 1-6 months post-infection/enrollment, including: depression (Patient Health Questionnaire-9), anxiety (General Anxiety Disorder-7), fatigue (PROMIS® Fatigue 7a), and cognitive function (PROMIS® Cognitive Function 8a and PROMIS® Cognitive Function abilities 8a). Multivariable Poisson regression models compared participants with and without SARS-CoV-2 infection history on these measures, adjusting for sex, ethnicity, active-duty status, age, and months post-first positive or enrollment of questionnaire completion (MPFP/E); models for fatigue and cognitive function were also adjusted for depression and anxiety scores.
The study population included 2383 participants who completed all five instruments within six MPFP/E, of whom 687 (28.8%) had at least one positive SARS-CoV-2 test. Compared to those who had never tested positive for SARS-CoV-2, the positive group was more likely to meet instrument-based criteria for depression (15.4% vs 10.3%, p<0.001), fatigue (20.1% vs 8.0%, p<0.001), impaired cognitive function (15.7% vs 8.6%, p<0.001), and impaired cognitive function abilities (24.3% vs 16.3%, p<0.001). In multivariable models, SARS-CoV-2 positive participants, assessed at an average of 2.7 months after infection, had increased risk of moderate to severe depression (RR: 1.44, 95% CI 1.12-1.84), fatigue (RR: 2.07, 95% CI 1.62-2.65), impaired cognitive function (RR: 1.64, 95% CI 1.27-2.11), and impaired cognitive function abilities (RR: 1.41, 95% CI 1.15-1.71); MPFP/E was not significant.
Participants with a history of SARS-CoV-2 infection were up to twice as likely to report cognitive impairment and fatigue as the group without prior SARS-CoV-2 infection. These findings underscore the continued importance of preventing SARS-CoV-2 infection and while time since infection/enrollment was not significant through 6 months of follow-up, this highlights the need for additional research into the long-term impacts of COVID-19 to mitigate and reverse these neuropsychological outcomes.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Europe’s capacity to explore the envisaged pathways that achieve its near- and long-term energy and climate objectives needs to be significantly enhanced. In this perspective, we discuss how this ...capacity is supported by energy and climate-economy models, and how international modelling teams are organised within structured communication channels and consortia as well as coordinate multi-model analyses to provide robust scientific evidence. Noting the lack of such a dedicated channel for the highly active yet currently fragmented European modelling landscape, we highlight the importance of transparency of modelling capabilities and processes, harmonisation of modelling parameters, disclosure of input and output datasets, interlinkages among models of different geographic granularity, and employment of models that transcend the highly harmonised core of tools used in model inter-comparisons. Finally, drawing from the COVID-19 pandemic, we discuss the need to expand the modelling comfort zone, by exploring extreme scenarios, disruptive innovations, and questions that transcend the energy and climate goals across the sustainability spectrum. A comprehensive and comprehensible multi-model framework offers a real example of “collective” science diplomacy, as an instrument to further support the ambitious goals of the EU Green Deal, in compliance with the EU claim to responsible research.
•EU energy & climate policy can benefit from a harmonised European modelling landscape.•Transparency, harmonisation, interlinkages, and granularity aspects are highlighted.•Employment of models transcending the highly harmonised core of models is stressed.•Disruptive innovations, extremes, and broad sustainability questions must be explored.•Policy responsiveness, international cooperation & science diplomacy can be enhanced.
Mass customization and product platform design can exploit the benefits of modularity and provide personalized devices at competitive costs through economies of scope. However, customization-intense ...platforms can have thousands of potential configurations, whose development and verification must be prioritized. This paper develops a value analysis methodology that is able to rank alternative platform configurations according to customers’ preferences. It introduces Logit value, a definition of value based on a well-known stated choice model and explains the five steps of platform-based value analysis. Since product platforms are complex technical systems, particular attention is given to the gathering of information, the automatic generation of platform architectures and the visualization of results. A case study based on Google ARA’s Spiral-2 modular smart phone concept demonstrates an application of the methodology and shows its potential benefits. The case study leverages data from a conjoint analysis and survey of 200 potential customers in Puerto Rico and a generated set of over 21,000 potential configurations of which less than 1% are shown to be non-dominated. The value analysis identifies module types that are compatible with the modular product platform and appear in a high percentage of Pareto architectures. Knowledge pertaining to non-dominated configurations can provide insights into module development strategy and verification/validation activities.
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