Nutrition-Based Modulation of Poly-ADP-Ribosylation and its possible role in Alzheimer’s disease

Alzheimer’s Disease (AD) is the most common neurodegenerative disease and the main reason of dementia in the elderly. On the pathological point of view, it is characterized by extracellular aggregates of amyloid peptides and intracellular deposits of tau protein. These deposits affect neuron viability and functions by inducing (among other pathological pathways) oxidative stress and triggering mitochondrial dysfunction. It is now evident that free radicalinduced oxidative damage is strongly involved in the pathogenesis of AD. Oxidative damage occurs early in disease pathogenesis and can exacerbate its progression. Post-mortem brain of individuals affected by AD, evidenced an extensive state of oxidative stress compared to healthy controls; markers of increased oxidation include, among others, DNA damage. DNA damage can induce the activity of the enzyme poly (ADP-ribose) polymerase 1 (PARP-1) that catalyze the reaction of poly (ADP-ribosylation). This post-translational modification modulates the functions of proteins involved in many physiological processes such as gene expression, maintenance of genomic stability and cell death. Therefore, inhibiting PARP-1 activity can represent a possible new strategy to reduce the impact of the oxidative stress in AD as well as in other neurodegenerative diseases. Here we discuss the role of nutrients in modulating PARP-1 activity and its perspective potential application

Functional decline in residents living in nursing homes : a systematic review of the literature

Objectives To describe the functional dependence progression over time in older people living in nursing homes (NHs). Design A systematic review of the literature was performed. Studies involving individuals 65 years and older living in NHs, describing their functional decline, improvement or stability in activities of daily living (ADLs), were eligible. The search strategy was applied in MedLine, Cochrane, CINAHL, and SCOPUS databases; aimed at identifying an unbiased and complete list of studies, searching by hand was also performed. The methodological quality of the 27 studies included was assessed. Results Functional trajectories were documented mainly through multicenter study design including sample size ranging from 2 to 9336 NHs, from 1983 to 2011 throughout a single or multiple follow-ups (>20). The average rate of decline was expressed in different metrics and periods of time: from 3 months with a decline of −0.13 points of 28, to 6 months (−1.78 points of 2829) to 1.85 years (−0.5 points of 6). Eating and toileting were the most documented ADLs and the decline is approximately 0.4 points and 0.2 to 0.4 points of 5 a year, respectively. Among the covariates, individual factors, such as cognitive status, were mainly considered, whereas only 13 studies considered facility-level factors. Conclusions Findings report the slow functional decline mainly in women living in US NHs, in years when residents were admitted with a low or medium degree of functional dependence. Considering that in recent years residents have been admitted to NHs with higher-level functional dependence, studies measuring each single ADL, using standardized instruments capable of capturing the signs of decline, stability, or improvement are strongly recommended. Among the covariates, evaluation of both individual and facility-level factors, which may affect functional decline, is also suggested

Environment, epigenetics and neurodegeneration: Focus on nutrition in Alzheimer's disease

Many different environmental factors (nutrients, pollutants, chemicals, physical activity, lifestyle, physical and mental stress) can modulate epigenetic markers in the developing and adult organism. Epigenetics, in turn, can cause and is associated with several neurodegenerative and aging-dependent human diseases. Alzheimer's disease certainly represents one of the most relevant neurodegenerative disorders due to its incidence and its huge socio-economic impact. Therefore, it is easy to understand why recent literature focuses on the epigenetic modifications associated with Alzheimer's disease and other neurodegenerative disorders. One of the most intriguing and, at the same time, worrying evidence is that even "mild" environmental factors (such as behavioral or physical stress) as well as the under-threshold exposure to pollutants and chemicals, can be effective. Finally, even mild nutrients disequilibria can result in long-lasting and functional alterations of many epigenetic markers, although they don't have an immediate acute effect. Therefore, we will probably have to re-define the current risk threshold for many factors, molecules and stresses. Among the many different environmental factors affecting the epigenome, nutrition represents one of the most investigated fields; the reasons are probably that each person interacts with nutrients and that, in turn, nutrients can modulate at molecular level the epigenetic biochemical pathways. The role that nutrition can exert in modulating epigenetic modifications in Alzheimer's disease will be discussed with particular emphasis on the role of B vitamins and DNA methylation

Solar hybrid thermal energy system using multiple evaporator loop thermosyphons

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Mecânica, Florianópolis, 2023.Coletores solares que utilizam a tecnologia de termossifões bifásicos têm recebido atenção crescente devido a sua alta eficiência térmica e baixos gradientes de temperatura durante a operação. No entanto, estes aparelhos não conseguem compensar a ausência de radiação solar, limitando sua aplicação. Assim, neste trabalho, são estudados os termosifões bifásicos em circuito (LTS na sigla em inglês) com dois evaporadores independentes, visando aplicações de energia solar térmica híbrida, onde um evaporador é alimentado por calor solar e o outro por uma fonte de calor alternativa (backup). Duas configurações de LTS foram desenvolvidas e testadas: uma com dois LTSs independentes associados em série e a outra compreendendo um arranjo com dois evaporadores independentes associados em paralelo. Ambas as configurações foram testadas sob as seguintes condições: testes em regime permanente, experimentos simulando intermitência solar e, por fim, testes simulando o funcionamento do dispositivo durante um dia típico. O evaporador solar exibiu os mesmos níveis de resistência térmica para ambas as configurações em série e paralelo. Para o evaporador alimentado pela fonte alternativa, a configuração em paralelo apresentou resistências térmicas gerais mais baixas, com oscilações de temperatura e instabilidades observadas para as menores taxas de calor aplicadas no evaporador. Nos testes de intermitência solar, o evaporador alimentado pela fonte alternativa no arranjo paralelo foi capaz de compensar a ausência solar em intervalos de tempo 47% menores, em média, quando comparado com a configuração em série. Nos testes de operação diária, a configuração em série foi capaz de manter níveis estáveis de temperatura do vapor, independentemente das variações na distribuição do calor imposto aos evaporadores. Um modelo teórico para os termossifões em circuito com evaporadores múltiplos foi formulado, considerando operação em regime permanente e utilizando a analogia com circuitos de resistência elétrica. O modelo exibiu boa concordância com valores experimentais para taxas de calor médias a altas, que correspondem às condições onde não foram observadas instabilidades. As resistências do evaporador alimentado pela fonte alternativa (backup) e resistências do evaporador solar exibiram erros médios de 15% e 29,9%, respectivamente quando comparadas aos valores experimentais nas faixas de operação sem instabilidade.Abstract: Solar collectors using thermosyphon technology have received increasing attention due to their high thermal efficiency and isothermal operation, but are unable to self-compensate for the absence of solar radiation, limiting their application. Thus, in this work, two-phase loop thermosyphons (LTS), with two independent evaporators, are studied aiming for hybrid solar thermal energy applications, where one evaporator is powered by solar heat and the other is powered by a backup heat source. Two LTS configurations were developed and tested: one with two LTS associated in series and the other comprising one loop with two independent evaporators in parallel. Both configurations were tested under the following conditions: steady state tests, experiments simulating solar intermittence and tests simulating device operation throughout a typical day. The solar evaporator exhibited the same resistance levels for both series and parallel configurations. For the backup evaporator, the parallel configuration displayed lower overall thermal resistances, with temperature oscillations and instabilities observed for the lower heat input rates. In the solar intermittence tests, the backup evaporator in the parallel arrangement was able to compensate for solar absence 47% quicker, in average, when compared to the series configuration. While operating under different heat input rate distributions in the daily operation tests, the series configuration was able to maintain stable vapor temperature levels, independent of the variation of the heat input rate with time. A theoretical model for the multiple evaporator loop thermosyphons under steady state operation was formulated using the thermal resistance network analogy, exhibiting good agreement for medium to higher heat input rates, conditions where no instabilities were observed, with backup evaporator resistances and solar evaporator resistances displaying average errors of 15% and 29.9%, respectively

S-adenosylmethionine and superoxide dismutase 1 synergistically counteract Alzheimer's disease features progression in tgCRND8 mice

Recent evidence emphasizes the role of dysregulated one-carbon metabolism in Alzheimer's Disease (AD). Exploiting a nutritional B-vitamin deficiency paradigm, we have previously shown that PSEN1 and BACE1 activity is modulated by one-carbon metabolism, leading to increased amyloid production. We have also demonstrated that S-adenosylmethionine (SAM) supplementation contrasted the AD-like features, induced by B-vitamin deficiency. In the present study, we expanded these observations by investigating the effects of SAM and SOD (Superoxide dismutase) association. TgCRND8 AD mice were fed either with a control or B-vitamin deficient diet, with or without oral supplementation of SAM + SOD. We measured oxidative stress by lipid peroxidation assay, PSEN1 and BACE1 expression by Real-Time Polymerase Chain Reaction (PCR), amyloid deposition by ELISA assays and immunohistochemistry. We found that SAM + SOD supplementation prevents the exacerbation of AD-like features induced by B vitamin deficiency, showing synergistic effects compared to either SAM or SOD alone. SAM + SOD supplementation also contrasts the amyloid deposition typically observed in TgCRND8 mice. Although the mechanisms underlying the beneficial effect of exogenous SOD remain to be elucidated, our findings identify that the combination of SAM + SOD could be carefully considered as co-adjuvant of current AD therapies

Analysis of ring laser gyroscopes including laser dynamics

Inertial sensors stimulate very large interest, not only for their application but also for fundamental physics tests. Ring laser gyros, which measure angular rotation rate, are certainly among the most sensitive inertial sensors, with excellent dynamic range and bandwidth. Large area ring laser gyros are routinely able to measure fractions of prad/s, with high duty cycle and bandwidth, providing fast, direct and local measurement of relevant geodetic and geophysical signals. Improvements of a factor $10-100$ would open the windows for general relativity tests, as the GINGER project, an Earth based experiment aiming at the Lense-Thirring test at $1\%$ level. However, it is well known that the dynamics of the laser induces non-linearities, and those effects are more evident in small scale instruments. Sensitivity and accuracy improvements are always worthwhile, and in general there is demand for high sensitivity environmental study and development of inertial platforms, where small scale transportable instruments should be used. We discuss a novel technique to analyse the data, aiming at studying and removing those non-linearity. The analysis is applied to the two ring laser prototypes GP2 and GINGERINO, and angular rotation rate evaluated with the new and standard methods are compared. The improvement is evident, it shows that the back-scatter problem of the ring laser gyros is negligible with a proper analysis of the data, improving the performances of large scale ring laser gyros, but also indicating that small scale instruments with sensitivity of nrad/s are feasible.Comment: 9 pages and 7 figure

Stiffening effects-controlling sizing procedure of ADAS dampers in seismic retrofit of frame structures

Added Damping and Stiffness (ADAS) steel dissipators are among the most classical devices installed in dissipative bracing systems for the advanced seismic retrofit of frame buildings. An energy-based sizing procedure is formulated in this study for this class of dampers, where the total number of constituting plates is directly related, without iterative steps, to the supplementary damping energy required to jointly reduce stress states in structural members and storey drifts. The stiffening effects of the dissipative braces are expressly controlled, so as to compensate for the increase in storey shears induced by their incorporation in the frame skeleton. The sizing procedure is demonstratively applied to the retrofit design of a 6-storey reinforced concrete building, to explicate and discuss the use of its analytical relations and relevant limitations in practice. The evaluation of the seismic performance of the structure in retrofitted conditions allows comparing the response of the dissipative bracing system with the hypotheses formulated at the sizing stage

The conformational evolution of elongated polymer solutions tailors the polarization of light-emission from organic nanofibers

Polymer fibers are currently exploited in tremendously important technologies. Their innovative properties are mainly determined by the behavior of the polymer macromolecules under the elongation induced by external mechanical or electrostatic forces, characterizing the fiber drawing process. Although enhanced physical properties were observed in polymer fibers produced under strong stretching conditions, studies of the process-induced nanoscale organization of the polymer molecules are not available, and most of fiber properties are still obtained on an empirical basis. Here we reveal the orientational properties of semiflexible polymers in electrospun nanofibers, which allow the polarization properties of active fibers to be finely controlled. Modeling and simulations of the conformational evolution of the polymer chains during electrostatic elongation of semidilute solutions demonstrate that the molecules stretch almost fully within less than 1 mm from jet start, increasing polymer axial orientation at the jet center. The nanoscale mapping of the local dichroism of individual fibers by polarized near-field optical microscopy unveils for the first time the presence of an internal spatial variation of the molecular order, namely the presence of a core with axially aligned molecules and a sheath with almost radially oriented molecules. These results allow important and specific fiber properties to be manipulated and tailored, as here demonstrated for the polarization of emitted light.Comment: 45 pages, 10 figures, Macromolecules (2014

BORDER CROSSINGS: CONVERSATIONS ACROSS DISCIPLINES AND CULTURES

The Spring 1997 PROVOST\u27S LECTURE SERIES, presented by the Institute for the Study of Culture and Society (ICS), offers a series of events which explore cultural interactions at the crossroads between social realities and cultural worlds. The series includes talks and events by interdisciplinary scholar and performance artist Coco Fusco; Third World scholar Barbara Harlow; and African-American cultural critic Michael Awkward. Bringing these nationally known scholars and artists to our learning community at Bowling Green State University marks an attempt to dare to cross borders between the known and unknown ; to gather a group of scholars, artists, and individuals who are dedicated to cultural equity and international rights; and to take ourselves there where we do not expect, are not expected to be. Borders thus cease to be dividing lines and instead, as Elsbeth Probyn has noted, become those places at the limits of who we think we are and where we can articulate, respect and use our differences to produce new knowledge.https://scholarworks.bgsu.edu/ics_fellow_lectures/1123/thumbnail.jp

Real World Operation of a Complex Plug-in Hybrid Electric Vehicle: Analysis of Its CO2 Emissions and Operating Costs

Plug-in hybrid electric vehicles (pHEVs) could represent the stepping stone to move towards a more sustainable mobility and combine the benefits of electric powertrains with the high range capability of conventional vehicles. Nevertheless, despite the huge potential in terms of CO2 emissions reduction, the performance of such vehicles has to be deeply investigated in real world driving conditions considering also the CO2 production related to battery recharge which, on the contrary, is currently only partially considered by the European regulation to foster the diffusion of pHEVs. Therefore, this paper aims to assess, through numerical simulation, the real performance of a test case pHEV, the energy management system (EMS) of which is targeted to the minimization of its overall CO2 emissions. The paper highlights, at the same time, the relevance of the CO2 production related to the battery recharge from the power grid. Different technologies mixes used to produce the electricity required for the battery recharge are also taken into account in order to assess the influence of this parameter on the vehicle CO2 emissions. Finally, since the operating cost still represents the main driver in orienting the customer’s choice, an alternative approach for the EMS, targeted to the minimization of this variable, is also analyzed