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11.
12.
Andrielli Morais de Oliveira Flávio de Andrade Silva Eduardo de Moraes Rego Fairbairn Romildo Dias Toledo Filho 《Materials and Structures》2018,51(3):65
This paper reports the experimental findings on the tensile behavior of strain-hardening cement-based composites (SHCC). The composites were subjected to the combined effects of elevated temperatures and internal moisture condition. Uniaxial tensile tests on dumbbell-shaped SHCC specimens with in situ temperature control were performed at 22, 60 and 100 °C. In addition, the effect of the internal humidity of SHCC (95, 50, 20 and 0%) coupled to the elevated temperatures was investigated. It was shown that the tensile strength decreases and the strain capacity increases with an increase in temperature. The influence of the internal moisture conditions was more significant in high temperatures. The strain capacity reduced significantly with a decrease in the humidity level. The crack pattern of the SHCC specimens was determined. Furthermore, single fiber pullout tests were performed under the considered high temperatures condition. Finally, the results are discussed based on the thermogravimetry analysis of the PVA fiber, alterations on its microstructure and surface coating. 相似文献
13.
Bruno R. de Araújo Tiago Guerreiro Manuel J. Fonseca Joaquim A. Jorge João M. Pereira Monica Bordegoni Francesco Ferrise Mario Covarrubias Michele Antolini 《Journal of Real-Time Image Processing》2010,5(2):73-90
Currently, the design of aesthetic products is a process that requires a set of activities where digital models and physical
mockups play a key role. Typically, these are modified (and built) several times before reaching the desired design, increasing
the development time and, consequently, the final product cost. In this paper, we present an innovative design environment
for computer-aided design (CAD) surface analysis. Our system relies on a direct visuo-haptic display system, which enables
users to visualize models using a stereoscopic view, and allows the evaluation of sectional curves using touch. Profile curves
are rendered using an haptic device that deforms a plastic strip, thanks to a set of actuators, to reproduce the curvature
of the shape co-located with the virtual model. By touching the strip, users are able to evaluate shape characteristics, such
as curvature or discontinuities (rendered using sound), and to assess the surface quality. We believe that future computer-aided
systems (CAS)/CAD systems based on our approach will contribute in improving the design process at industrial level. Moreover,
these will allow companies to reduce the product development time by reducing the number of physical mockups necessary for
the product design evaluation and by increasing the quality of the final product, allowing a wider exploration and comparative
evaluation of alternatives in the given time. 相似文献
14.
Marcelo Godoy Simões Tiago Davi Curi Busarello Abdullah Saad Bubshait Farnaz Harirchi José Antenor Pomilio Frede Blaabjerg 《International journal of control》2016,89(4):850-870
This paper presents interactive smart battery-based storage (BBS) for wind generator (WG) and photovoltaic (PV) systems. The BBS is composed of an asymmetric cascaded H-bridge multilevel inverter (ACMI) with staircase modulation. The structure is parallel to the WG and PV systems, allowing the ACMI to have a reduction in power losses compared to the usual solution for storage connected at the DC-link of the converter for WG or PV systems. Moreover, the BBS is embedded with a decision algorithm running real-time energy costs, plus a battery state-of-charge manager and power quality capabilities, making the described system in this paper very interactive, smart and multifunctional. The paper describes how BBS interacts with the WG and PV and how its performance is improved. Experimental results are presented showing the efficacy of this BBS for renewable energy applications. 相似文献
15.
Sandra Brasil Mariateresa Allocca Salvador C. M. Magrinho Inês Santos Madalena Raposo Rita Francisco Carlota Pascoal Tiago Martins Paula A. Videira Florbela Pereira Giuseppina Andreotti Jaak Jaeken Kristin A. Kantautas Ethan O. Perlstein Vanessa dos Reis Ferreira 《International journal of molecular sciences》2022,23(15)
Advances in research have boosted therapy development for congenital disorders of glycosylation (CDG), a group of rare genetic disorders affecting protein and lipid glycosylation and glycosylphosphatidylinositol anchor biosynthesis. The (re)use of known drugs for novel medical purposes, known as drug repositioning, is growing for both common and rare disorders. The latest innovation concerns the rational search for repositioned molecules which also benefits from artificial intelligence (AI). Compared to traditional methods, drug repositioning accelerates the overall drug discovery process while saving costs. This is particularly valuable for rare diseases. AI tools have proven their worth in diagnosis, in disease classification and characterization, and ultimately in therapy discovery in rare diseases. The availability of biomarkers and reliable disease models is critical for research and development of new drugs, especially for rare and heterogeneous diseases such as CDG. This work reviews the literature related to repositioned drugs for CDG, discovered by serendipity or through a systemic approach. Recent advances in biomarkers and disease models are also outlined as well as stakeholders’ views on AI for therapy discovery in CDG. 相似文献
16.
17.
Tiago F. A. Santos Edwar A. Torres Tahiana F. C. Hermengildo Antonio J. Ramirez 《Welding International》2016,30(5):338-347
Usually, a workpiece is deformed during friction stir welding due to high applied loads. Consequently, fully and consolidated friction stir-welded joints as well as tool life time can be affected promoting unscheduled manufacturing stops, which favour decreasing the welding productivity. Furthermore, the workforce is dislocated to not predicted maintenance steps. This work proposes the development of a special ceramic backing to joining and processing material using FSW technologies. Four ceramic deposits were tested over a steel plate, which allowed selecting those with less porosity and, thus, better strength. This backing allowed us to obtain full penetration welds for duplex stainless steels, to high forces during engagement for high-strength low-alloy steels and to obtain consolidated aluminium–steel dissimilar joints. For the last one, there was not adherence of the soft material in the workpiece. In addition, the ceramic backing allowed us to confine the heat and plasticized metal, as well as develop established welding parameters. 相似文献
18.
Viviane Muniz da Silva Fragoso Carla Patrícia de Morais Coura Luanda Yanaan Hoppe Marília Amável Gomes Soares Dilson Silva Celia Martins Cortez 《International journal of molecular sciences》2016,17(1)
The aim of this work was to study the interaction of sulpiride with human serum albumin (HSA) and bovine serum albumin (BSA) through the fluorescence quenching technique. As sulpiride molecules emit fluorescence, we have developed a simple mathematical model to discriminate the quencher fluorescence from the albumin fluorescence in the solution where they interact. Sulpiride is an antipsychotic used in the treatment of several psychiatric disorders. We selectively excited the fluorescence of tryptophan residues with 290 nm wavelength and observed the quenching by titrating HSA and BSA solutions with sulpiride. Stern-Volmer graphs were plotted and quenching constants were estimated. Results showed that sulpiride form complexes with both albumins. Estimated association constants for the interaction sulpiride–HSA were 2.20 (±0.08) × 104 M−1, at 37 °C, and 5.46 (±0.20) × 104 M−1, at 25 °C. Those for the interaction sulpiride-BSA are 0.44 (±0.01) × 104 M−1, at 37 °C and 2.17 (±0.04) × 104 M−1, at 25 °C. The quenching intensity of BSA, which contains two tryptophan residues in the peptide chain, was found to be higher than that of HSA, what suggests that the primary binding site for sulpiride in albumin should be located next to the sub domain IB of the protein structure. 相似文献
19.
Seigo Nagashima Anderson Azevedo Dutra Mayara Pezzini Arantes Rafaela Chiuco Zeni Carolline Konzen Klein Flvia Centenaro de Oliveira Giulia Werner Piper Isadora Drews Brenny Marcos Roberto Curcio Pereira Rebecca Benicio Stocco Ana Paula Camargo Martins Eduardo Morais de Castro Caroline Busatta Vaz de Paula Andra Novaes Moreno Amaral Cleber Machado-Souza Cristina Pellegrino Baena Lucia Noronha 《International journal of molecular sciences》2022,23(3)
Mast cells (MCs) have relevant participation in inflammatory and vascular hyperpermeability events, responsible for the action of the kallikrein–kinin system (KKS), that affect patients inflicted by the severe form of COVID-19. Given a higher number of activated MCs present in COVID-19 patients and their association with vascular hyperpermeability events, we investigated the factors that lead to the activation and degranulation of these cells and their harmful effects on the alveolar septum environment provided by the action of its mediators. Therefore, the pyroptotic processes throughout caspase-1 (CASP-1) and alarmin interleukin-33 (IL-33) secretion were investigated, along with the immunoexpression of angiotensin-converting enzyme 2 (ACE2), bradykinin receptor B1 (B1R) and bradykinin receptor B2 (B2R) on post-mortem lung samples from 24 patients affected by COVID-19. The results were compared to 10 patients affected by H1N1pdm09 and 11 control patients. As a result of the inflammatory processes induced by SARS-CoV-2, the activation by immunoglobulin E (IgE) and degranulation of tryptase, as well as Toluidine Blue metachromatic (TB)-stained MCs of the interstitial and perivascular regions of the same groups were also counted. An increased immunoexpression of the tissue biomarkers CASP-1, IL-33, ACE2, B1R and B2R was observed in the alveolar septum of the COVID-19 patients, associated with a higher density of IgE+ MCs, tryptase+ MCs and TB-stained MCs, in addition to the presence of intra-alveolar edema. These findings suggest the direct correlation of MCs with vascular hyperpermeability, edema and diffuse alveolar damage (DAD) events that affect patients with a severe form of this disease. The role of KKS activation in events involving the exacerbated increase in vascular permeability and its direct link with the conditions that precede intra-alveolar edema, and the consequent DAD, is evidenced. Therapy with drugs that inhibit the activation/degranulation of MCs can prevent the worsening of the prognosis and provide a better outcome for the patient. 相似文献
20.
The brain is one of the most energy-consuming organs in the mammalian body, and synaptic transmission is one of the major contributors. To meet these energetic requirements, the brain primarily uses glucose, which can be metabolized through glycolysis and/or mitochondrial oxidative phosphorylation. The relevance of these two energy production pathways in fulfilling energy at presynaptic terminals has been the subject of recent studies. In this review, we dissect the balance of glycolysis and oxidative phosphorylation to meet synaptic energy demands in both resting and stimulation conditions. Besides ATP output needs, mitochondria at synapse are also important for calcium buffering and regulation of reactive oxygen species. These two mitochondrial-associated pathways, once hampered, impact negatively on neuronal homeostasis and synaptic activity. Therefore, as mitochondria assume a critical role in synaptic homeostasis, it is becoming evident that the synaptic mitochondria population possesses a distinct functional fingerprint compared to other brain mitochondria. Ultimately, dysregulation of synaptic bioenergetics through glycolytic and mitochondrial dysfunctions is increasingly implicated in neurodegenerative disorders, as one of the first hallmarks in several of these diseases are synaptic energy deficits, followed by synapse degeneration. 相似文献