3,530 research outputs found

    Irreversible spherical model and its stationary entropy production rate

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    The nonequilibrium stationary state of an irreversible spherical model is investigated on hypercubic lattices. The model is defined by Langevin equations similar to the reversible case, but with asymmetric transition rates. In spite of being irreversible, we have succeeded in finding an explicit form for the stationary probability distribution, which turns out to be of the Boltzmann-Gibbs type. This enables one to evaluate the exact form of the entropy production rate at the stationary state, which is non-zero if the dynamical rules of the transition rates are asymmetric

    Expressions of the Individual’s behavior in Digital Network: Education in a Technological Society

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    The article assumes that the behavior of expressions of individuals is related to the digital network, in which forms of human relationships are being forged in order to understand differently the process of teaching and learning with autonomy that can generate a new way of thinking, creating values and representations. This may resize behaviors in individuals and affect the perception of the subject in relation to themselves and others. New technologies, consumption and media influence shape and build the contemporary psyche. Thus, it becomes essential to consider the force with which the new messaging serving media plays in order to socialize and in the individual subjectivity. In this context, new challenges for education that allow the birth of studies and concepts, in order to explain this new reality and to contribute to the art of teaching and learning. One of these, therefore, will be part of this work, which is called Informational Normosis or Informatosis

    Proposal of a virtual collaborative news environment: an interdisciplinary study

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    The main objective of this work is to demonstrate the advances made by the CATI research group with regard to the proposal to create a virtual collaborative news environment (AVNC) , to be initially implemented at the Northern Fluminense Darcy Ribeiro State University(UENF) through the Postgraduate Program in Cognition and Language. This interdisciplinary environment involves concepts from the area of communication, administration and information technology and seeks to meet the demands of generation, storage, retrieval, processing and transmission of information in this digital age. The AVNC involves three research fronts: rethinking the logic of news production, structuring a platform that is collaborative and defining what a business and management model should be that can give sustainability to this environment. In today\u27s world, it is important to consider the reader\u27s increasingly active participation in journalism, through information and communication technologies, thanks to the social changes that come with them. In times of cyberspace and cyberculture, it is necessary to rethink the dynamics of journalistic production. For this, authors like Pierre Lévy, Lúcia Santaella, Henry Jenkins, Caio Túlio Costa, among others were searched. In an era in which forms of collaborative ownership prevail, the platform being considered in this research follows the 3C collaboration model, according to Michalsky, Mamani, and Gerosa. A global platform where individuals interact, communicate, collaborate and gather information requires a business model and management that assists in managing the collaborative virtual news environment. For this, we used authors such as Alex Osterwalder, Eric Flamholtz, Siqueira and Crispim, Campos, among others. With this, an increasingly intelligent and collaborative environment is expected, with the active participation of all the agents involved. That is, what is proposed is the total interaction of the Internet user-reader

    Prevalence of Oral Pain and Barriers to use of Emergency Oral Care Facilities Among Adult Tanzanians.

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    Oral pain has been the major cause of the attendances in the dental clinics in Tanzania. Some patients postpone seeing the dentist for as long as two to five days. This study determines the prevalence of oral pain and barriers to use of emergency oral care in Tanzania. Questionnaire data were collected from 1,759 adult respondents aged 18 years and above. The study area covered six urban and eight rural study clusters, which had been selected using the WHO Pathfinder methodology. Chi-square tests and logistic regression analyses were performed to identify associations.\ud Forty two percent of the respondents had utilized the oral health care facilities sometimes in their lifetime. About 59% of the respondents revealed that they had suffered from oral pain and/or discomfort within the twelve months that preceded the study, but only 26.5% of these had sought treatment from oral health care facilities. The reasons for not seeking emergency care were: lack of money to pay for treatment (27.9%); self medication (17.6%); respondents thinking that pain would disappear with time (15.7%); and lack of money to pay for transport to the dental clinic (15.0%). Older adults were more likely to report that they had experienced oral pain during the last 12 months than the younger adults (OR = 1.57, CI 1.07-1.57, P < 0.001). Respondents from rural areas were more likely report dental clinics far from home (OR = 5.31, CI = 2.09-13.54, P < 0.001); self medication at home (OR = 3.65, CI = 2.25-5.94, P < 0.001); and being treated by traditional healer (OR = 5.31, CI = 2.25-12.49, P < 0.001) as reasons for not seeking emergency care from the oral health care facilities than their counterparts from urban areas. Oral pain and discomfort were prevalent among adult Tanzanians. Only a quarter of those who experienced oral pain or discomfort sought emergency oral care from oral health care facilities. Self medication was used as an alternative to using oral care facilities mainly by rural residents. Establishing oral care facilities in rural areas is recommended

    It Takes Two to Tango, Part II : Synthesis of A-Ring Functionalised Quinones Containing Two Redox-Active Centres with Antitumour Activities

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    In 2021, our research group published the prominent anticancer activity achieved through the successful combination of two redox centres (ortho-quinone/para-quinone or quinone/seleniumcontaining triazole) through a copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction. The combination of two naphthoquinoidal substrates towards a synergetic product was indicated, but not fully explored. Herein, we report the synthesis of 15 new quinone-based derivatives prepared from click chemistry reactions and their subsequent evaluation against nine cancer cell lines and the murine fibroblast line L929. Our strategy was based on the modification of the A-ring of paranaphthoquinones and subsequent conjugation with different ortho-quinoidal moieties. As anticipated, our study identified several compounds with IC50 values below 0.5 µM in tumour cell lines. Some of the compounds described here also exhibited an excellent selectivity index and low cytotoxicity on L929, the control cell line. The antitumour evaluation of the compounds separately and in their conjugated form proved that the activity is strongly enhanced in the derivatives containing two redox centres. Thus, our study confirms the efficiency of using A-ring functionalized para-quinones coupled with ortho-quinones to obtain a diverse range of two redox centre compounds with potential applications against cancer cell lines. Here as well, it literally takes two for an efficient tango

    Anandamide Effects in a Streptozotocin-Induced Alzheimer’s Disease-Like Sporadic Dementia in Rats

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    Alzheimer’s disease (AD) is characterized by multiple cognitive deficits including memory and sensorimotor gating impairments as a result of neuronal and synaptic loss. The endocannabinoid system plays an important role in these deficits but little is known about its influence on the molecular mechanism regarding phosphorylated tau (p-tau) protein accumulation – one of the hallmarks of AD –, and on the density of synaptic proteins. Thus, the aim of this study was to investigate the preventive effects of anandamide (N-arachidonoylethanolamine, AEA) on multiple cognitive deficits and on the levels of synaptic proteins (syntaxin 1, synaptophysin and synaptosomal-associated protein, SNAP-25), cannabinoid receptor type 1 (CB1) and molecules related to p-tau degradation machinery (heat shock protein 70, HSP70), and Bcl2-associated athanogene (BAG2) in an AD-like sporadic dementia model in rats using intracerebroventricular (icv) injection of streptozotocin (STZ). Our hypothesis is that AEA could interact with HSP70, modulating the level of p-tau and synaptic proteins, preventing STZ-induced cognitive impairments. Thirty days after receiving bilateral icv injections of AEA or STZ or both, the cognitive performance of adult male Wistar rats was evaluated in the object recognition test, by the escape latency in the elevated plus maze (EPM), by the tone and context fear conditioning as well as in prepulse inhibition tests. Subsequently, the animals were euthanized and their brains were removed for histological analysis or for protein quantification by Western Blotting. The behavioral results showed that STZ impaired recognition, plus maze and tone fear memories but did not affect contextual fear memory and prepulse inhibition. Moreover, AEA prevented recognition and non-associative emotional memory impairments induced by STZ, but did not influence tone fear conditioning. STZ increased the brain ventricular area and this enlargement was prevented by AEA. Additionally, STZ reduced the levels of p-tau (Ser199/202) and increased p-tau (Ser396), although AEA did not affect these alterations. HSP70 was found diminished only by STZ, while BAG2 levels were decreased by STZ and AEA. Synaptophysin, syntaxin and CB1 receptor levels were reduced by STZ, but only syntaxin was recovered by AEA. Altogether, albeit AEA failed to modify some AD-like neurochemical alterations, it partially prevented STZ-induced cognitive impairments, changes in synaptic markers and ventricle enlargement. This study showed, for the first time, that the administration of an endocannabinoid can prevent AD-like effects induced by STZ, boosting further investigations about the modulation of endocannabinoid levels as a therapeutic approach for AD
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