888 research outputs found
Cassini observations of the thermal plasma in the vicinity of Saturn's main rings and the F and G rings
The ion mass spectrometer on Cassini detected enhanced ion flux near Saturn's main rings that is consistent with the presence of atomic and molecular oxygen ions in the thermal plasma. The ring "atmosphere'' and "ionosphere'' are likely produced by UV photosputtering of the icy rings and subsequent photoionization of O-2. The identification of the O+ and O-2(+) ions is made using time-of-flight analysis and densities and temperatures are derived from the ion counting data. The ion temperatures over the main rings are a minimum near synchronous orbit and increase with radial distance from Saturn as expected from ion pick up in Saturn's magnetic field. The O-2(+) temperatures provide an estimate of the neutral O-2 temperature over the main rings. The ion mass spectrometer also detected significant O-2(+) outside of the main rings, near the F ring. It is concluded that between the F and G rings, the heavy ion population most likely consists of an admixture of O-2(+) and water group ions O+, OH+, and H2O+
Synergistic antimicrobial interaction between honey and phage against Escherichia coli biofilms
CEB Annual Meeting 2017Chronic wounds that take months, years or may even never heal present a major biological and financial problem on both individual patients and the broader health system. Chronic wounds afford a hostile environment of damaged tissues that allow bacterial proliferation and further wound colonization. Wound colonization by bacterial biofilms is one of the main obstacles of chronic wounds healing. Biofilms are structured communities of bacterial cells enclosed in a self-produced polymeric matrix and adhered to an inert or living surface. Escherichia coli is among the most common colonizers of infected wounds and it is a prolific biofilm former. Living in biofilm communities, cells are protected, become more difficult to control and eradicate, and less susceptible to antibiotic therapy. Due to the vast increase of antibiotic resistant bacteria, there is a renewed interestin pre-antibiotic therapies. Years before the discovery of modern antibiotics, bacteriophages(phages) that are bacterial viruses, and beehive products such as honey were extensively used for their antimicrobial properties. Phages, are the natural bacterial enemies and have proven efficacy towards antibiotic-resistant bacteria, have self-replicating nature, do not interfere with the commensal flora and many studies acknowledge that phages can destroy, tovarying extent, mono and mixed biofilm populations. Honey, on the other hand, has a broad spectrum antibacterial activity against bacteria and its high viscosity provides a protective barrier against infections being suitable for skincare, promoting the wound healing, tissue regeneration and anti-inflammatory process. This work presents insights into the proceedings triggering E.coli biofilm control with phage, two Portuguese(PT) honeys and their combination, achieved through standard antimicrobial activity assays, zeta potential and flow cytometry studies and further visual insights sought by SEM and TEM microscopy.This study was supported by FCT under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorteoperation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio
CENÁRIOS HIDROCLIMÁTICOS FUTUROS (2011-2040) PARA A REPRESA DE PARAIBUNA, SP, BRASIL: SUBSÍDIOS PARA A TRANSPOSIÇÃO ENTRE BACIAS HIDROGRÁFICAS
A crise hídrica em São Paulo nos anos de 2014-2015 gerou muitos conflitos pelo uso da água, visto que os totais de precipitação abaixo da normal climatológica impactaram diretamente os níveis dos reservatórios que abastecem a região. Neste contexto, a transposição das águas da bacia hidrográfica do rio Paraíba do Sul para o Sistema Cantareira, que abastece a Região Metropolitana de São Paulo foi proposta pelas autoridades para mitigar os impacto desta crise e abastecer sua população, sendo necessário analisar se a transposição proposta atenderá à sua demanda. Para investigar as condições futuras de quantidade de água da represa de Paraibuna, foram utilizados dados de simulação climática do modelo atmosférico global HadCM3/Eta, considerando o cenário SRES A1B do IPCC, para os períodos passado (1961-1990) e futuro (2011-2040). Os resultados estimam que até 2040 aumentará a demanda em 123% pelas águas da bacia hidrográfica da rio Paraíba do Sul, e em apenas 40% dos anos poderá ocorrer a transferência de água entre as bacias hidrográficas, sendo que na década de 2030 apenas em três anos esta transposição será viável. Isto demonstra a baixa efetividade da proposta e coloca em evidência a solução encontrada para a crise de abastecimento de São Paulo
A systems approach to policy evaluation
There is growing interest in evaluating policy implementation in ways that grapple with the complexity of the process. This article offers an example of using systems methodology to explore how the child protection policy in child contact centres has functioned in practice. Rather than just asking the traditional evaluation question “is it working?” this study sought to understand how the policy was working and how it was interpreted as it interacted with other systems, producing conflicts, local variation and emergent effects. It illustrates how the systems concepts of ‘emergence’, ‘local rationality’, ‘socio-technical systems’ and ‘feedback for learning’ can contribute new knowledge and understanding to a complex policy evaluation problem
A systematic review of protocol studies on conceptual design cognition
This paper reports the first systematic review and synthesis of protocol studies on conceptual design cognition. 47 protocol studies from the domains of architectural design, engineering design, and product de-sign engineering were reviewed towards answering the following re-search question: What is our current understanding of the cognitive processes involved in conceptual design tasks carried out by individual designers? Studies were found to reflect three viewpoints on the cognitive nature of designing, namely: design as search; design as ex-ploration; and design activities. Synthesising the findings of individual studies yielded a classification of cognitive processes involved in con-ceptual design tasks, described in different terms across different viewpoints. Towards a common terminology, these processes are posi-tioned within the cognitive psychology literature, revealing seven basic types of process that appear to be fundamental to designing across all viewpoints: memory (working and long term); visual perception; men-tal imagery; attention; semantic association; cognitive control; and higher-order processes, e.g. analysis and reasoning. The development of common cognitive models of conceptual design, grounded in a sci-entifically rigorous understanding of design cognition, is identified as an avenue for future research
Febrile seizures and mechanisms of epileptogenesis: insights from an animal model.
Temporal lobe epilepsy (TLE) is the most prevalent type of human epilepsy, yet the causes for its development, and the processes involved, are not known. Most individuals with TLE do not have a family history, suggesting that this limbic epilepsy is a consequence of acquired rather than genetic causes. Among suspected etiologies, febrile seizures have frequently been cited. This is due to the fact that retrospective analyses of adults with TLE have demonstrated a high prevalence (20-->60%) of a history of prolonged febrile seizures during early childhood, suggesting an etiological role for these seizures in the development of TLE. Specifically, neuronal damage induced by febrile seizures has been suggested as a mechanism for the development of mesial temporal sclerosis, the pathological hallmark of TLE. However, the statistical correlation between febrile seizures and TLE does not necessarily indicate a causal relationship. For example, preexisting (genetic or acquired) 'causes' that result independently in febrile seizures and in TLE would also result in tight statistical correlation. For obvious reasons, complex febrile seizures cannot be induced in the human, and studies of their mechanisms and of their consequences on brain molecules and circuits are severely limited. Therefore, an animal model was designed to study these seizures. The model reproduces the fundamental key elements of the human condition: the age specificity, the physiological temperatures seen in fevers of children, the length of the seizures and their lack of immediate morbidity. Neuroanatomical, molecular and functional methods have been used in this model to determine the consequences of prolonged febrile seizures on the survival and integrity of neurons, and on hyperexcitability in the hippocampal-limbic network. Experimental prolonged febrile seizures did not lead to death of any of the seizure-vulnerable populations in hippocampus, and the rate of neurogenesis was also unchanged. Neuronal function was altered sufficiently to promote synaptic reorganization of granule cells, and transient and long-term alterations in the expression of specific genes were observed. The contribution of these consequences of febrile seizures to the epileptogenic process is discussed
A pilot randomized controlled trial for a videoconference-delivered mindfulness-based group intervention in a nonclinical setting
Technology is increasingly being integrated into the provision of therapy and mental health interventions. While the evidence base for technology-led delivery of mindfulness-based interventions is growing, one approach to understanding the effects of technology-delivered elements includes so-named blended programs that continue to include aspects of traditional face-to-face interaction. This arrangement offers unique practical advantages, and also enables researchers to isolate variables that may be underlying the effects of technology-delivered interventions. The present study reports on a pilot videoconference-delivered mindfulness-based group intervention offered to university students and staff members with wait-list controls. Apart from the first session of the six-week course, the main facilitator guided evening classes remotely via online videoconferencing, with follow-up exercises via email. Participants Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation were taught a variety of mindfulness-based exercises such as meditation, breathing exercises, mindful tasting, as well as the concepts underpinning such practice. Participants completed pre- and post-intervention questionnaires on depression, anxiety, repetitive negative thinking, dysfunctional attitudes, positive and negative affect, self-compassion, compassion for others, and mindfulness. For participants who attended at least five of the six sessions, scores on all outcome measures improved significantly post intervention and remained stable at three-week follow up. The videoconference-delivered mindfulness-based group intervention appears to provide a viable alternative format to standard mindfulness programs where the facilitator and participants need to live in close physical proximity with each other
The evolution of sex-specific virulence in infectious diseases
Fatality rates of infectious diseases are often higher in men than women. Although this difference is often attributed to a stronger immune response in women, we show that differences in the transmission routes that the sexes provide can result in evolution favouring pathogens with sex-specific virulence. Because women can transmit pathogens during pregnancy, birth or breast-feeding, pathogens adapt, evolving lower virulence in women. This can resolve the long-standing puzzle on progression from Human T-cell Lymphotropic Virus Type 1 (HTLV-1) infection to lethal Adult T-cell Leukaemia (ATL); a progression that is more likely in Japanese men than women, while it is equally likely in Caribbean women and men. We argue that breastfeeding, being more prolonged in Japan than in the Caribbean, may have driven the difference in virulence between the two populations. Our finding signifies the importance of investigating the differences in genetic expression profile of pathogens in males and females
Energetic and physical limitations on the breaching performance of large whales
The considerable power needed for large whales to leap out of the water may represent the single most expensive burst maneuver found in nature. However, the mechanics and energetic costs associated with the breaching behaviors of large whales remain poorly understood. In this study we deployed whale-borne tags to measure the kinematics of breaching to test the hypothesis that these spectacular aerial displays are metabolically expensive. We found that breaching whales use variable underwater trajectories, and that high-emergence breaches are faster and require more energy than predatory lunges. The most expensive breaches approach the upper limits of vertebrate muscle performance, and the energetic cost of breaching is high enough that repeated breaching events may serve as honest signaling of body condition. Furthermore, the confluence of muscle contractile properties, hydrodynamics, and the high speeds required likely impose an upper limit to the body size and effectiveness of breaching whales
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