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Oxygen Transfer and Fragmentation of Aspergillus niger Pellets in Stirred Tank and Concentric-Duct Airlift Bioreactors

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Industrial Biotechnology 2020年第2期16卷 67-74页

作者： Buffo, Mariane M. Esperança, Mateus N. Béttega, Rodrigo Farinas, Cristiane S. Badino, Alberto C. Graduate Program of Chemical Engineering Federal University of São Carlos São Carlos13565-905 Brazil Federal Institute of Education Science and Technology of São Paulo Campus Capivari Capivari Brazil Embrapa Instrumentation São Carlos Brazil

The hydrodynamic environment in bioreactors is an important parameter because cultivation conditions that provide satisfactory oxygen transfer rates tend to be harmful to microorganisms, due to the effect of shear on the cellular structure. Consequently, it is a challenge to find the ideal set of bioreactor operating conditions that favor production of the metabolites of interest. The present work evaluated the fragmentation of Aspergillus niger pellets in two different types of bioreactor: a conventional stirred tank bioreactor (STB) and a concentric-duct airlift (CDA) bioreactor. Both were operated under similar oxygen transfer or shear conditions. Oxygen transfer was quantified by means of the volumetric oxygen transfer coefficient (kLa). The shear condition was determined using the average shear rate (γav), obtained using computational fluid dynamics (CFD), together with pellet fragmentation. The findings showed that the CDA bioreactor caused less fragmentation of the pellets, compared to the STB, when both systems were operated with the same kLa values. For similar fragmentation levels, the kLa value for the CDA bioreactor was 38% higher than observed for the STB. Considering the results for both bioreactor models, the fragmentation of A. niger pellets, represented by the variation of the average normalized A. niger pellet equivalent diameter (Deq/Deq,0) after fragmentation assays of 4 h duration (Δfrag), exhibited a linear relation with γav (R2 = 0.97). The CDA bioreactor also presented advantages in terms of specific power consumption and mass transfer efficiency. These results should assist in the selection of suitable bioreactor models and operating conditions, in order to improve the efficiency of industrial production of bio-based products. © 2020, Mary Ann Liebert, Inc., publishers 2020.

关键词： Bioreactors

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Built environments for physical activity: a longitudinal descriptive analysis of Sao Paulo city, Brazil

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Cities and Health 2023年第1期7卷 137-147页

作者： Teixeira, Inaian Pignatti Barbosa, João Paulo dos Anjos Souza Barrozo, Ligia Vizeu Hino, Adriano Akira Ferreira Nakamura, Priscila Missaki Andrade, Douglas Roque Mavoa, Suzanne Turrell, Gavin Reis, Rodrigo Siqueira Florindo, Alex Antonio Minas Gerais State University Passos Brazil Study Research and Scientific Support Group Minas Gerais State University Passos Brazil Physical Activity Epidemiology Group University of Sao Paulo São Paulo Brazil Department of Geography School of Philosophy Literature and Human Sciences University of Sao Paulo Sao Paulo Brazil Health Sciences Graduate Program School of Medicine and Life Sciences Pontifical Catholic University of Paraná Curitiba Brazil Federal Institute of Education Science and Technology of South of Minas Gerais- Campus Muzambinho Muzambinho Brazil School of Arts Sciences and Humanities University of Sao Paulo Sao Paulo Brazil Graduate Program in Social Change and Political Participation School of Arts Sciences and Humanities University of Sao Paulo Sao Paulo Brazil Melbourne School of Population & Global Health University of Melbourne Melbourne Australia Victoria Environmental Protection Authority (EPA) VIC Australia Centre for Urban Research RMIT University Melbourne Australia Health Research Institute University of Canberra Canberra Australia People health and Place Unit Prevention Research Center Brown School Washington University in Saint Louis St Louis MO United States Graduate Program in Nutrition in Public Health School of Public Health University of Sao Paulo Sao Paulo Brazil

City policies and plans play an important role in promoting physical activity through changes in the urban design and transportation systems. The objectives of this study were to describe longitudinal changes in the built environment relevant to leisure-time physical activity and active travel in Sao Paulo city, Brazil, between 2015 and 2020;to describe these changes according to regions of the city, census tracts’ income, and buffer zones around the residences of participants in a cohort. Using data from public online libraries, cross-checked with the specific municipal and state secretariats, the following were measured: public squares, parks, sports facilities, community clubs, outdoor gyms, bike paths, train or subway stations, bus terminals, and primary health care units. To quantify these attributes around the residences, four different buffers: 500 m and 1000 m radial buffers and 500 m and 1000 m network buffers were adopted. An increase was observed in outdoor gyms (+109.6%), bike paths (+67.7%), train or subway stations, bus terminals (+15.4%), sports facilities (+12.0%), and public squares (+8.7%). However, the changes differed according to the region, census tract income, and residential area. The results can serve to foster a discussion on the effects of local policies being executed. In addition, this study highlights important disparities in cities through the different levels evaluated. © 2022 Informa UK Limited, trading as Taylor & Francis Group.

关键词： active transportation Built environment cohort inequality leisure-time physical activity monitoring

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Association between ambient air particulate matter and human health impacts in northern Thailand (vol 13, 12753, 2023)

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SCIENTIFIC REPORTS 2023年第1期13卷 1-15页

作者： Supasri, Titaporn Gheewala, Shabbir H. Macatangay, Ronald Chakpor, Anurak Sedpho, Surat Atmospheric Research Unit National Astronomical Research Institute of Thailand Chiang Mai Thailand Energy Engineering Program Faculty of Engineering Chiang Mai University Chiang Mai Thailand Institute of Environmental Science and Meteorology University of the Philippines Diliman Quezon City Philippines The Joint Graduate School of Energy and Environment (JGSEE) King Mongkut’s University of Technology Thonburi Bangkok Thailand Center of Excellence on Energy Technology and Environment Ministry of Higher Education Science Research and Innovation Bangkok Thailand School of Energy and Environment University of Phayao Phayao Thailand

Air pollution in Thailand is regarded as a serious health threat, especially in the northern region. High levels of particulate matter (PM2.5and PM10) are strongly linked to severe health consequences and mortality. This study analyzed the relationship between exposure to ambient concentrations of PM2.5and PM10by using data from the Pollution Control Department of Thailand and the burden of disease due to an increase in the ambient particulate matter concentrations in northern Thailand. This study was conducted using the Life Cycle Assessment methodology considering the human health damage impact category in the ReCiPe 2016 method. The results revealed that the annual average years of life lived with disability from ambient PM2.5in northern Thailand is about 41,372 years, while from PM10it is about 59,064 years per 100,000 population. The number of deaths from lung cancer and cardiopulmonary diseases caused by PM2.5were approximately 0.04% and 0.06% of the population of northern Thailand, respectively. Deaths due to lung cancer and cardiopulmonary diseases caused by PM10, on the other hand, were approximately 0.06% and 0.08%, respectively. The findings expressed the actual severity of the impact of air pollution on human health. It can provide valuable insights for organizations in setting strategies to address air pollution. Organizations can build well-informed strategies and turn them into legal plans by exploiting the study’s findings. This ensures that their efforts to tackle air pollution are successful, in accordance with regulations, and contribute to a healthier, more sustainable future guidelines on appropriate practices of air pollution act/policy linkage with climate change mitigation.

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Preliminary Exploration on the Application of Saussure Sign Concept in Bio-Inspired Design: A Case of Tiantoushui Doll-Design

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World Journal of Engineering and technology 2021年第3期9卷 548-554页

作者： Yu-Chun Yao Shiu-Hua Wu Ai-Li Wang Graduate Program of Sustainable Tourism and Recreation Management National Taichung University of Education Taichung Department of Digital Media Design Hsiuping University of Science and Technology Taichung School of Art and Design Dalian Polytechnic University Dalian

Simply, shape bionics is to extract an image feature of natural objects, and most of the techniques for transforming and presenting are focused on metaphorical effects. In particular, the extraction process of metaphor design seems to be related to the concept of Saussure signs. Therefore, this research took the doll design of the Tiantoushui community in Changhua County, Taiwan as an example and attempted to use the Saussure concept to extract and evaluate the signs of bio-inspired design. The results showed that a total of three doll works symbolized respectively rice, guava, and pomelo implied the signification of local region by integrating the Saussure code image with the sign-image of the regional nature and transforming its content into “commodity design” and further transferring into “the product value of cultural and creative”. In addition, the specific extraction process included 1) Extraction of image—adjectives in creative products;2) Meaning space of image—adjec- tives in creative products;3) Extraction and determination of design elements of creative products, and 4) Combined the sensibility of creative products and design elements to derive design rules. After preliminary exploration of the extraction steps above, a concrete and efficient bio-inspired design process was proposed in this work. Besides, it was inferred that if further combined with the post-modern design style, it may not only simplify the design elements of creative products but also enhance the design connotations in the future.

关键词： Bio-Inspired Design Saussure Sign Concept Doll-Design Code-Image

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Thermomechanical Behavior and Corrosion Resistance of a 316 L Austenitic Stainless Steel

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Materials sciences and Applications 2020年第4期11卷 217-233页

作者： Rafael P. Ferreira Carmem C. F. Nascimento Gedeon S. Reis Eden S. Silva Samuel F. Rodrigues Graduate Program in Materials Engineering Federal Institute of Education Science and Technology of Maranhao (IFMA) Sao Luis Brazil

Hot-formed components are constantly exposed to hostile environments with corrosive substances. Microstructural changes caused by thermomechanical processing can be predicted to increase the corrosion resistance of austenitic stainless steels. The objective of this study is to understand the relationship between the dynamic softening mechanisms and corrosion resistance, thus optimizing the hot-forming process. In the current work, the dynamic recrystallization (DRX) behavior of AISI 316 L austenitic stainless steel was studied in the temperature range of 1273 - 1423 K and strain-rate range of 0.1 - 5.0 s-1 using physical simulation. Subsequently, potentiodynamic polarization tests and scanning electron microscopy were performed on the hot-deformed samples to investigate the influence of temperature and strain-rate on the corrosion resistance and mechanical properties. The results indicated that the DRX fractions increased under low-temperature and high strain-rate conditions, resulting in grain refinement. The potentiodynamic polarization tests indicated that the dynamically recovered samples demonstrated high resistance to corrosion compared with the DRX samples. The best route found for the investigated alloy was for the strain to be applied at a temperature of 1423 K and a strain rate of 0.1 s-1.

关键词： 316 L Austenitic Stainless Steel Softening Phenomena Corrosion

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Multimodal Sentiment Analysis using Kernel Based Support Vector Machine

Multimodal Sentiment Analysis using Kernel Based Support Vec...

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Advanced Technologies in Intelligent Control, Environment, Computing & Communication Engineering (ICATIECE), International Conference on

作者： V Sunil Kumar Piyush Kumar Pareek Victor Hugo Costa De Albuquerque Ashish Khanna Deepak Gupta Madhumala R B Department Artificial Intelligence & Machine Learning Nitte Meenakshi Institute of Technology Bengaluru Graduate Program in Telecommunication Engineering Federal Institute of Education Science and Technology of Ceará Fortaleza Brazil Department of Teleinformatics Engineering Federal University of Ceará Brazil CSE Dept Maharaja Agrasen Institute of Technology GGSIPU Department of ISE Dayananda Sagar Academy of Technology and Management Bangalore

ISBN: (纸本)9781665493970

There has been a steady expansion in the number of social websites, electronic media outlets, and blogging services, all of which contribute a large number of user messages such as comments, reviews, and opinions from customers. The quantity of these signals, which are used to evaluate the quality of a wide variety of goods and services, is rather substantial. As a result, it is challenging to monitor and identify the feelings of customers. As a result, a method known as Sentiment Analysis (SA), also known as Opinion Mining (OM), was developed. This method gathers data from the internet by using Natural Language Processing (NLP) strategies and then analyses people's thoughts. It does this by extracting subjective information from the words, assessing opinions, and quantifying positive and negative evaluations. The end result is a conclusion about the specific entity, which may be an organisation, the public, or a product. The NLP first gathers the views, and then those opinions are sorted into positive, neutral, and negative categories. Both the marketing promotion and the customer's ability to choose the most appropriate product for their needs may be improved by doing an analysis. The purpose of this study is to evaluate the use of different machine learning and swarm intelligence optimization methods to perform sentiment analysis on data derived from movie reviews. This study helps many businesses increase their profits while simultaneously lowering the number of problems caused by a certain product. Within the scope of this investigation, three distinct models of sentiment analysis were investigated. An effective method for doing sentiment analysis known as a Hybrid Kernel based Support Vector Machine (HKSVM) has been presented. The preprocessing that is described here is meant to cut down on the data inconsistencies and get rid of the data that isn't needed. After that, the Expectation Maximization (EM) technique is used in order to identify an outlier. After t

关键词： Support vector machines Sentiment analysis Analytical models Sensitivity Veins Tagging Probabilistic logic

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Microstructure, Properties and Crystallographic Orientation of Novel Austenitic Fe-26mn-0.4c Steel Under Hot Torsion Process

SSRN

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SSRN 2023年

作者： da Silva Lima, Marcos Natan França Schmalz, Guilherme Luis Loureiro, Rodrigo de Carvalho Paes Ferreira, João Carlos Rodrigues, Samuel Filgueiras Muñoz, Jessica Calvo Cabrera Marrero, José María de Abreu, Hamilton Ferreira Gomes Department of Metallurgical and Materials Engineering Federal University of Ceará Campus do Pici bloco 729 Fortaleza Ceará60020-181 Brazil Graduate Program in Materials Engineering Federal Institute of Education Science and Technology of Maranhão Sao Luis65030-005 Brazil Department Materials Science and Metallurgical Engineering Universitat Politècnica de Catalunya: Catalunya Bl. I Barcelona08930 Spain

An experimental austenitic twin-induced plasticity (TWIP) steel was deformed under hot torsion tests. Two different total equivalent strains were employed in order to raise its yield strength while keeping reasonable toughness. The material was strained isothermally at 900 °C with a low strain rate of 0.05 s–1. The effects of torsional deformation on the microstructure, texture and mechanical properties of TWIP-FeMnCCr steel were investigated and compared with the as-received samples. X-Ray Diffraction (XRD) measurements were performed to identify the phases present in the metal before and after the thermomechanical process. Scanning electron microscopy (SEM), Electron backscatter diffraction (EBSD), Orientation distribution function (ODF) analysis and tensile experiments complemented the investigation of this research. The main deformation mechanism changed from conventional sliding inside the grain to nucleated twinning from the grain boundaries, which led to the decrease of the grains to less than 1 μm (UFG - Ultrafine Grains). The results indicate that the deformation mechanisms transition dependent on grain size is associated with the discontinuous flow profile of the material. This was due to changes in the density of dislocations within the grain and the movement of dislocations around the yield point. No martensitic transformation was detected during the strain and neither from the twinning mechanism in the microstructure after the torsion deformation. The best balance between high strength and good ductility (920 MPa and 52%) was obtained after the total equivalent strain of 2.6. It was verified that the employed thermomechanical schedule affects the displacement of the substructure with the formation of subgrains influencing the hardening behavior, texture and yield strength of the metal. © 2023, The Authors. All rights reserved.

关键词： Textures

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Construction and Evaluation of Situational System for Introducing Interactive technology into Ecotourism of Active Aging Group 22nd

Construction and Evaluation of Situational System for Introd...

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22nd International Conference on Human Computer Interaction, HCII 2020

作者： Lu, Li-Shu Wu, PeiFen Huan, Guan-Yuan Department and Graduate School of Digital Media Design National Yunlin University of Science and Technology Douliu Taiwan Department of Information Management and Master Program in Digital Content Technology and Management National Changhua University of Education Changhua Taiwan

ISBN: (纸本)9783030601485

Due to the issue of population aging faced by Taiwan, the government is implementing policies on encouraging the elderly to engage in social activities in their life after retirement, so as to enable them to enjoy a contented and happy retirement life and further forget their ages. In the population aging society, the elderly have an increasingly greater demand for ecotourism. Therefore, in this study, by taking ecotourism as an example, a research on the engagement of the elderly in technology enhanced interactive scenarios of ecotourism was conducted. Purpose of this study was mainly to propose the design system of technology enhanced interactive scenarios suitable for experience of the elderly. In this study, experience demands of the elderly were understood through relevant literature review, preliminary survey and field survey. Subsequently, design concepts of interactive scenarios were proposed through Scenario Approach and a prototype of interactive scenario was designed through Rapid Prototyping Method. Research results: a total of 8 concepts of interactive scenarios were proposed in this study through demand investigation, including provision of experience information, voice guide experience, enhancement of experience fun, trigger of experience scenario, enhancement of intellectual fun, basic knowledge query, enhancement of sensory experience, and sharing and memory. At last, the prototype of "i-Travel" interactive experience scenario was proposed through Prototyping Method. The interactive system consists of 8 interactive scenario concepts, experience contents and navigation design, design of scenario navigation APP, etc. Results of this study will be applied for subsequent assessment and validation of scenario experience awareness of this system. © 2020, Springer Nature Switzerland AG.

关键词： Surveys

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AI-Based Feature Extraction and Cosine Similarity for Automation of Student Learning Assessment

AI-Based Feature Extraction and Cosine Similarity for Automa...

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Information technology (ACIT)

作者： Bambang Dwi Wijanarko Bachtiar Rosilah Binti Hassan Dina Fitria Murad Ridho Bramulya Ihsan Yaya Heryadi Engkos Achmad Kuncoro Eka Julianti Computer Science Department BINUS Online Learning Bina Nusantara University Jakarta Indonesia Master of English Education Graduate School Universitas Terbuka Jakarta Indonesia Center for Cyber Security Faculty of Information Science and Technology Universiti Kebangsaan Malaysia Bangi Selangor Malaysia Information Systems Department BINUS Online Learning Bina Nusantara University Jakarta Indonesia Manajemen Department BINUS Online Learning Bina Nusantara University Jakarta Indonesia Computer Science Department BINUS Graduate Program-Doctor of Computer Science Bina Nusantara University Jakarta Indonesia Management Department BINUS Business School Undergraduate Program Bina Nusantara University Jakarta Indonesia Information System Department Universitas Terbuka Jakarta Indonesia

This research is ongoing research into the student learning process which aims to develop artificial intelligence-based technology to calculate essay exam scores automatically, based on the textual proximity of students' answers to the answer key. This research uses an approach based on natural language processing (NLP) and text analysis. Feature extraction was carried out using the BERT model and similarity comparison using the Cosine distance method. Model evaluation was carried out using sensitivity and specificity tests. The model evaluation results show a sensitivity of 98.21%, which means this assessment model is able to detect positive cases well.

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Structural, Morphological, Optical, and Antibacterial Activities of Zinc Oxide Nanopowders: A Comparative Study of Green and Soft Chemical Synthesis

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Advances in Materials science and Engineering 2022年第0期2022卷

作者： Siriya Pushpa, K. Catherine Sakthivel, P. Saravanakumar, K. Anuradha, N. Sankaranarayanan, R.K. Paulraj, Mosae Selvakumar Post-Graduate and Research Department of Physics Bon Secours College for Women Tamil Nadu Thanjavur613006 India Centre for Materials Science Department of Physics Science and Humanities Faculty of Engineering Karpagam Academy of Higher Education Coimbatore641021 India Mallasamudram Tamil Nadu Namakkal637503 India Centre for Nano Science and Technology Department of Chemistry Chennai Institute of Technology Tamil Nadu Kundrathur600069 India AUW Chemistry Hub Science and Math Program Asian University for Women Chattogram Bangladesh

Zinc oxide, a well-known inorganic metal oxide in nanoparticle form, has outstanding antibacterial properties. In this work, the authors focus on determining ZnO nanoparticles’ structural, optical, and antibacterial activity. A simple soft chemical route synthesizes C-ZnO nanoparticles chemically, while the green synthesis method is used to prepare G-ZnO nanoparticles. Ocimum tenuiflorum leaf extract was used to prepare G-ZnO nanopowders. These samples are investigated and compared in terms of their structural, morphological, optical, and antibacterial properties. According to XRD investigations, the synthesized ZnO nanopowders possess a hexagonal structure. The particle size of G-ZnO is smaller than that of C-ZnO nanoparticles. The XPS result revealed the binding and interactions between molecules. The FTIR study confirmed the presence of molecules and their vibrations. UV-vis-DRS spectroscopy was used to investigate optical properties such as reflectance and band gap. The grain size of the G-ZnO nanopowders was decreased, and oxygen vacancy was produced. The antibacterial efficiency of plant extracts against two different bacterial strains, S. aureus (Gram-positive) and *** (Gram-negative), has been studied and reported. Copyright © 2022 K. Catherine Siriya Pushpa et al.

关键词： ZnO nanoparticles

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