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131.
The paper presents design and verification of regression models for prediction of pipe conveyor belt contact forces on idler rolls. Their advantage is in the fact that they have been created according to the real experimental measurement. The obtained models correspond with real operational conditions. The concept of the experimental rig at the Technical University of Košice is designed so that it represents 8 m long section of pipe conveyor. The conveyor belt is an object with action of tension force and at the same time it takes the initiative in the contact force formation. Several criteria have been used to verify the presented regression models. The tensioning force 9000, 12,000 and 15,000 N have MPE of prediction error less than 5%. About 120,000 measured values have been processed during the evaluations which correspond to approximately 15,000 results from experimental measurements. 相似文献
132.
Z.L. Wang G.F. NatererK.S. Gabriel R. GravelsinsV.N. Daggupati 《International Journal of Hydrogen Energy》2009
Copper–chlorine thermochemical cycles for hydrogen production are very promising water splitting cycles. In this paper, different types of copper–chlorine cycles with various numbers of steps are compared. The factors that determine the number and effective grouping of steps are analyzed. It is found that the water requirement in the hydrolysis step is affected by a combination of drying and hydrolysis steps. It is also found that hydrogen can be produced either from electrolysis of cuprous chloride, or from chlorination of copper by hydrogen chloride, which indicates a potential combination of disproportionation and chlorination steps. The major engineering advantages and disadvantages of these cycle variations with different amounts of steps will be analyzed and discussed. 相似文献
133.
Gabriel Nama Medoua Israël Lape Mbome T. Agbor-Egbe C. M. F. Mbofung 《Food chemistry》2005,90(4):597-601
Processing of Dioscorea dumetorum tubers into flour could be a means of adding a longer-term value to this tropical plant with a high nutritional potential but which presents a post-harvest hardening problem. This study was carried out in order to investigate the effect of storage under prevailing tropical ambient conditions (19–28 °C, RH 60–85%) for 56 days on the physicochemical characteristics of flours produced from hardened tubers. With the exception of bulk density, the results showed that all the physicochemical properties measured (water absorption capacity, oil absorption capacity, water solubility index, hydrophilic–lipophilic index, swelling capacity and least gelatinising concentration) were significantly influenced by tuber storage time (P<0.05). In general, the physicochemical indices increased with storage in at least two phases, from days 2 to 21 and from days 28 to 56. Since sprouting of most tubers was observed after 28 days of storage, the results suggest that post-harvest hardening and sprouting influence the above-mentioned indices of flours produced from D. dumetorum tubers. 相似文献
134.
135.
As ventilation filters accumulate particles removed from the airstream, they become emitters of sensory pollutants that degrade indoor air quality. Previously we demonstrated that an F7 bag-type filter that incorporates activated carbon (a “combination filter”) reduces this adverse effect compared to an equivalent filter without carbon. The aim of the present study was to examine how the amount of activated carbon (AC) used in combination filters affects their ability to remove both sensory offending pollutants and ozone. A panel evaluated the air downstream of four different filters after each had continuously filtered outdoor suburban air over a period of 6 months. Interim assessments (mid-term evaluation) were performed after 3 months. During both assessments, four unused filters, identical in type to the loaded filters, were also evaluated. The evaluated filters included a conventional F7 fiberglass filter and three modifications of a bag-type fiberglass combination filter: the “Heavy” corresponded to a commercially available filter containing 400 g of carbon per square meter of filter area, the “Medium” contained half as much carbon (200 g/m2), and the “Light” contained a quarter as much carbon (100 g/m2). Each filter was weighed at the beginning of the soiling period and after 3 and 6 months of service. Additionally, up- and down-stream ozone concentrations and filter pressure drops were measured monthly. Following 6 months of service, the air downstream of each of the combination filters was judged to be significantly better than the air downstream of the 6-month-old F7 filter, and was comparable to that from an unused F7 filter. Additionally, the combination filters removed more ozone from the air than the F7 filter, with their respective fractional removal efficiencies roughly scaling with their carbon content. 相似文献
136.
Brazilian city beaches are public spaces favoring citizens well-being. Urban studies relate built form and infrastructure with urban vitality and coastal studies underline uses as important for beach management, yet few researches relate form and infrastructure with beach uses. Understanding daily life as essential for public spaces and that spatial form relates with uses, this paper assesses time-based relationships between built and natural physical attributes and social life on the beaches of João Pessoa, a coastal city in North-east Brazil. Physical attributes are investigated at city scale - beach type, street network centrality and topography - and seafront scale - land uses, public/private interfaces, public infrastructure, beach sections and water quality. Beach social life was surveyed online, enquiring peoples' beach choice, visiting time and place, activities and evaluation. Infrastructure and street network follow topography and help configure shore and promenade for different landscapes. More central beaches have diverse land uses, well-equipped promenades and lighting and were popular night and day, while less central beaches had less infrastructure and were visited only by day. Findings highlight how physical attributes facilitate uses and, together with peoples’ evaluation, can inform urban beach design and planning. 相似文献
137.
Chiara Bellocchi Angelica Carandina Beatrice Montinaro Elena Targetti Ludovico Furlan Gabriel Dias Rodrigues Eleonora Tobaldini Nicola Montano 《International journal of molecular sciences》2022,23(5)
The autonomic nervous system (ANS) and the immune system are deeply interrelated. The ANS regulates both innate and adaptive immunity through the sympathetic and parasympathetic branches, and an imbalance in this system can determine an altered inflammatory response as typically observed in chronic conditions such as systemic autoimmune diseases. Rheumatoid arthritis, systemic lupus erythematosus, and systemic sclerosis all show a dysfunction of the ANS that is mutually related to the increase in inflammation and cardiovascular risk. Moreover, an interaction between ANS and the gut microbiota has direct effects on inflammation homeostasis. Recently vagal stimulation techniques have emerged as an unprecedented possibility to reduce ANS dysfunction, especially in chronic diseases characterized by pain and a decreased quality of life as well as in chronic inflammation. 相似文献
138.
Mohamed Haddad Roger Gaudreault Gabriel Sasseville Phuong Trang Nguyen Hannah Wiebe Theo Van De Ven Steve Bourgault Normand Mousseau Charles Ramassamy 《International journal of molecular sciences》2022,23(5)
The overall impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on our society is unprecedented. The identification of small natural ligands that could prevent the entry and/or replication of the coronavirus remains a pertinent approach to fight the coronavirus disease (COVID-19) pandemic. Previously, we showed that the phenolic compounds corilagin and 1,3,6-tri-O-galloyl-β-D-glucose (TGG) inhibit the interaction between the SARS-CoV-2 spike protein receptor binding domain (RBD) and angiotensin-converting enzyme 2 (ACE2), the SARS-CoV-2 target receptor on the cell membrane of the host organism. Building on these promising results, we now assess the effects of these phenolic ligands on two other crucial targets involved in SARS-CoV-2 cell entry and replication, respectively: transmembrane protease serine 2 (TMPRSS2) and 3-chymotrypsin like protease (3CLpro) inhibitors. Since corilagin, TGG, and tannic acid (TA) share many physicochemical and structural properties, we investigate the binding of TA to these targets. In this work, a combination of experimental methods (biochemical inhibition assays, surface plasmon resonance, and quartz crystal microbalance with dissipation monitoring) confirms the potential role of TA in the prevention of SARS-CoV-2 infectivity through the inhibition of extracellular RBD/ACE2 interactions and TMPRSS2 and 3CLpro activity. Moreover, molecular docking prediction followed by dynamic simulation and molecular mechanics Poisson–Boltzmann surface area (MMPBSA) free energy calculation also shows that TA binds to RBD, TMPRSS2, and 3CLpro with higher affinities than TGG and corilagin. Overall, these results suggest that naturally occurring TA is a promising candidate to prevent and inhibit the infectivity of SARS-CoV-2. 相似文献
139.
Marialuisa Aragona Caterina Porcino Maria Cristina Guerrera Giuseppe Montalbano Rosaria Laur Marzio Cometa Maria Levanti Francesco Abbate Teresa Cobo Gabriel Capitelli Jos A. Vega Antonino German 《International journal of molecular sciences》2022,23(5)
The brain-derived neurotrophic factor (BDNF) was discovered in the last century, and identified as a member of the neurotrophin family. BDNF shares approximately 50% of its amino acid with other neurotrophins such as NGF, NT-3 and NT-4/5, and its linear amino acid sequences in zebrafish (Danio rerio) and human are 91% identical. BDNF functions can be mediated by two categories of receptors: p75NTR and Trk. Intriguingly, BDNF receptors were highly conserved in the process of evolution, as were the other NTs’ receptors. In this review, we update current knowledge about the distribution and functions of the BDNF-TrkB system in the sensory organs of zebrafish. In fish, particularly in zebrafish, the distribution and functions of BDNF and TrkB in the brain have been widely studied. Both components of the system, associated or segregated, are also present outside the central nervous system, especially in sensory organs including the inner ear, lateral line system, retina, taste buds and olfactory epithelium. 相似文献
140.
Sanghee Lee Theresa R. Mendoza Danielle N. Burner Michelle T. Muldong Christina C. N. Wu Catalina Arreola-Villanueva Abril Zuniga Olga Greenburg William Y. Zhu Jamillah Murtadha Evodie Koutouan Naomi Pineda Hao Pham Sung-Gu Kang Hyun Tae Kim Gabriel Pineda Kathleen M. Lennon Nicholas A. Cacalano Catriona H. M. Jamieson Christopher J. Kane Anna A. Kulidjian Terry Gaasterland Christina A. M. Jamieson 《International journal of molecular sciences》2022,23(6)