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Modeling and Simulation of an Isothermal Suspension Polymerization Reactor for PMMA Production Using Python

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Advances in Chemical Engineering and Science 2017年第4期7卷 408-419页

作者： Aldo Okullo noah tibasiima Joshua Barasa Department of Chemistry Kyambogo University Kampala Uganda

This paper presents the modeling and simulation of a suspension polymerization for methyl methacrylate in an isothermal reactor to produce poly methyl methacrylate using Python 3.5. The numeral solution to the stiff ordinary differential equations was performed by building a custom module which was used with the inbuilt NumPy and matplotlib modules that come with the Anaconda python distro. Python was used in order to obtain a realistic solution that considers the gel, glass and cage effects that affect the non-linear polymerization kinetics established in literature. The results showed that a maximum monomer conversion of about 92.8% at a minimum batch time of about 2.2 hours could be achieved at the specified conditions to obtain a polydisperse polymer with an index of 27. It is further concluded that Python can be employed to perform similar studies with equal success as any other programming language.

关键词： Suspension Polymerization Modeling Simulation Python

Leveraging machine learning to generate a unified and complete building height dataset for Germany

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Energy and AI

Energy and AI 2024年第3期17卷 327-341页

作者： Kristina Dabrock noah Pflugradt Jann Michael Weinand Detlef Stolten Forschungszentrum Jülich GmbH Institute of Climate and Energy SystemsJülich Systems Analysis52425 JülichGermany RWTH Aachen University Chair for Fuel CellsFaculty of Mechanical Engineering52062 AachenGermany

Building geometry data is crucial for detailed, spatially-explicit analyses of the building stock in energy systems analysis and beyond. Despite the existence of diverse datasets and methods, a standardized and validated approach for creating a nation-wide unified and complete dataset of German building heights is not yet available. This study develops and validates such a methodology, combining different data sources for building footprints and heights and filling gaps in height data using an XGBoost machine learning algorithm. The XGBoost model achieves a mean absolute error of 1.78 m at the national level and between 1.52 m and 3.47 m at the federal state level. The goal is proving the applicability of the methodology at a large scale and creating a useful dataset. The resulting dataset is thoroughly evaluated on a building-by-building level and spatially resolved statistics on the quality of the dataset are reported. This detailed validation found that the building number and footprint area of German building stock is 90.31 % and 94.84 % correct, respectively, and the building height accuracy is 0.59 m at the national level. However, errors are not homogeneous across Germany and further research is needed into the impact of including additional datasets, especially for regions and building types with lower accuracies. This study proves that the chosen methodology is useful for generating a building height dataset and the workflow, with some modifications for regional data availability, can be transferred to other countries. The generated building dataset for Germany constitutes a valuable data basis for the research community in fields such as energy research, urban planning and building decarbonization policy development.

关键词： Machine learning XGBoost Building height Building footprint 3-D building data Geodata Spatial analysis

Protein-nucleic acid hybrid nanostructures for molecular diagnostic applications

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Nano Research 2024年第10期17卷 9003-9014页

作者： noah R.Sundah Yuxuan Seah Auginia Natalia Xiaoyan Chen Panida Cen Yu Liu Huilin Shao Institute for Health Innovation and Technology National University of SingaporeSingapore 117599Singapore Department of Biomedical Engineering College of Design and EngineeringNational University of SingaporeSingapore 117583Singapore Integrative Sciences and Engineering Programme NUS Graduate SchoolNational University of SingaporeSingapore 119077Singapore Institute of Molecular and Cell Biology Agency for ScienceTechnology and ResearchSingapore 138673Singapore Department of Surgery Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117597Singapore

Molecular diagnostic technologies empower new clinical opportunities in precision ***,existing approaches face limitations with respect to performance,operation and *** molecules including proteins and nucleic acids are being increasingly adopted as tools in the development of new molecular diagnostic *** particular,leveraging their complementary properties—the functional diversity of proteins and the precision programmability of nucleic acids—a wide range of protein–nucleic acid hybrid nanostructures have been *** hybrid structures take diverse forms,ranging from one-dimensional to three-dimensional hybrids,as static assemblies to dynamic machines,and possess myriad functions to recognize target biomarkers,encode vast information and execute catalytic *** by recent advances in this area of molecular nanotechnology,we review the state-of-art design and application of various types of protein–nucleic acid hybrid nanostructures for molecular diagnostics,and present an outlook on the challenges and opportunities for emerging pre-clinical and clinical applications,highlighting the promise for earlier detection,more refined diagnosis and highly tailored treatment decision that ultimately lead to improved patient outcomes.

关键词： molecular nanotechnology DNA-protein hybrid molecular diagnostics precision medicine

A systematic review of spatial disaggregation methods for climate action planning

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Energy and AI

Energy and AI 2024年第3期17卷 458-469页

作者： Shruthi Patil noah Pflugradt Jann M.Weinand Detlef Stolten Jürgen Kropp Institute of Energy and Climate Research Techno-economic Systems Analysis(IEK-3)Forschungszentrum JülichWilhelm-Johnen-StraßeJülich52425NRWGermany University of Potsdam Institute for Environmental Science and GeographyKarl-Liebknecht-Str.24-25Potsdam-Golm14476BrandenburgGermany Chair for Fuel Cells RWTH Aachen Universityc/o IEK-3Forschungszentrum JülichJülich52425NRWGermany Potsdam Institute for Climate Impact Research(PIK) Member of the Leibniz AssociationP.O.Box 601203PotsdamD-14412BrandenburgGermany

National-level climate action plans are often formulated broadly. Spatially disaggregating these plans to individual municipalities can offer substantial benefits, such as enabling regional climate action strategies and for assessing the feasibility of national objectives. Numerous spatial disaggregation approaches can be found in the literature. This study reviews and categorizes these. The review is followed by a discussion of the relevant methods for the disaggregation of climate action plans. It is seen that methods employing proxy data, machine learning models, and geostatistical ones are the most relevant methods for the spatial disaggregation of national energy and climate plans. The analysis offers guidance for selecting appropriate methods based on factors such as data availability at the municipal level and the presence of spatial autocorrelation in the *** the urgency of addressing climate change escalates, understanding the spatial aspects of national energy and climate strategies becomes increasingly important. This review will serve as a valuable guide for researchers and practitioners applying spatial disaggregation in this crucial field.

关键词： Spatial downscaling Proxy data Mass-preserving Climate action plans Spatial autocorrelation Machine learning Geostatistical models

Diverse experiences by active travel for carbon neutrality:A longitudinal study of residential context,daily travel and experience types

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Geography and Sustainability 2024年第3期5卷 459-469页

作者： Karl Samuelsson S.Anders Brandt Stephan Barthel noah Linder Nancy Joy Lim David Hallman Matteo Giusti Department of Building Engineering Energy Systems and Sustainability ScienceFaculty of Engineering and Sustainable DevelopmentUniversity of Gävle 80176 GävleSweden ISGlobal Barcelona Biomedical Research ParkDoctor Aiguader 8808003 BarcelonaSpain Department of Computer and Geospatial Sciences Faculty of Engineering and Sustainable DevelopmentUniversity of Gävle 80176 GävleSweden Stockholm Resilience Centre Stockholm University 10691 StockholmSweden Global Economic Dynamics and the Biosphere Royal Swedish Academy of ScienceLilla Frescativägen 4A 11418 StockholmSweden Department of Occupational Health Science and Psychology Faculty of Health and Occupational StudiesUniversity of Gävle 80176 GävleSweden School of Sustainability Civil and Environmental EngineeringFaculty of Engineering and Physical SciencesUniversity of SurreyGuildfordSurrey GU27XHUK

Two key goals for sustainable spatial planning are to promote low-carbon travel in daily life and to enhance human wellbeing through diverse human-environment ***,the integration of these goals has been *** study investigates the potential for experiential diversity via active travel in different resi-dential contexts within the Gävle city-region,*** 15 months,we collected spatiotemporal data from 165 participants,analyzing 4,362 reported experiences and 13,192 GPS-derived travel *** analysis uncovered a significant spatial discrepancy:while the travelled distances to locations of positive experiences typ-ically ranged from 1.5 km to 5 km,active travel predominated only within 1.5 *** discrepancy persisted across urban,suburban,and peripheral *** residents in different contexts reported the same types of experiences,urban dwellers travelled about 50%farther for nature experiences compared with other positive experiences,whereas peripheral dwellers travelled twice the distance for urbanicity experiences compared with other positive ***,urban residents mostly relied on active travel for urbanicity experiences and motorised travel for nature experiences,with the reverse trend observed among peripheral *** results illustrate the importance of spatial scale for promoting diverse positive experiences via active travel,re-gardless of residential *** planning strategies may include enhancing environmental diversity near homes and developing infrastructure that favours active over motorised travel for short to moderate distances.

关键词： Walking Biking Experiential diversity GPS data Smartphone app Topodiversity

Measurement of cryoelectronics heating using a local quantum dot thermometer in silicon

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Chip 2024年第3期3卷 1-7页

作者： Mathieu de Kruijf Grayson M.noah Alberto Gomez-Saiz John J.L.Morton M.Fernando Gonzalez-Zalba Quantum Motion 9 Sterling WayLondon N79HJUnited Kingdom London Centre for Nanotechnology University College London17-19 Gordon StreetLondon WC1H 0AHUnited Kingdom

Silicon technology offers the enticing opportunity for monolithic integration of quantum and classical electronic ***,the power consumption levels of classical electronics may compromise the local chip temperature and hence affect the fidelity of qubit *** the current work,a quantum-dot-based thermometer embedded in an industry-standard silicon fieldeffect transistor(FET)was adopted to assess the local temperature increase produced by an active FET placed in close *** impact of both static and dynamic operation regimes was thoroughly *** the FET was operated statically,a power budget of 45 nW at 100-nm separation was found,whereas at 216μm,the power budget was raised to 150μ*** temperature increase for the switch frequencies tested up to 10 MHz was observed when operating *** current work introduced a method to accurately map out the available power budget at a distance from a solid-state quantum processor,and indicated the possible conditions under which cryoelectronics circuits may allow the operation of hybrid quantum-classical systems.

关键词： Quantum dot Cryogenic electronics Thermometry Spin qubit Heat management

Abiotic Factors Associated with Abundance Dynamics and Antibiotic Multidrug Resistance of Escherichia coli and Enterococcus faecalis Isolated from Some Ombessa Aquatic Systems (Central Cameroon Region)

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Journal of Geoscience and Environment Protection 2024年第9期12卷 335-369页

作者： Lucie Leme Banock Blandine Pulchérie Tamatcho Kweyang Fabrice Ezo’o Mengo Stephane Arthur noah Eric Donald Mbo Zang Olive Vivien noah Ewoti Laboratory of Hydobiology and Environment Department of Animal Biology and Physiology Faculty of Sciences University of Yaounde 1 Yaounde Cameroon Laboratory of Microbiology of Soil and Environment Department of Microbiology Faculty of Sciences University of Yaounde 1 Yaounde Cameroon

The present study conducted in the town of Ombessa aims to assess the influence of abiotic factors on the abundance dynamics and antibiotic susceptibility of Escherichia coli and Enterococcus faecalis isolated from some aquatic systems from February to July 2022, monthly samples were taken at 10 water points used by the population (8 groundwater points and 2 surface water points). Samples were analyzed for physico-chemical parameters such as temperature, pH, electrical conductivity. Bacteriological variables such as BHAM, E. coli and E. faecalis abundances were also assessed. Antibiotic susceptibility of E. coli and E. faecalis was assessed using 06 antibiotics using the Kirby-Bauer diffusion disk method. The results show that bacterial abundances were the highest in surface waters. Bacterial densities were the highest in May and the lowest in February. The average densities recorded were 3845 CFU/100mL for BHAM, 380 CFU/100mL for E. coli and 14 CFU/100mL for E. faecalis in groundwater;and 8583 CFU/100mL for BHAM, 6878 CFU/100mL for E. coli and 812 CFU/100mL for E. faecalis in surface water. Antibiotic susceptibility tests showed that these bacterial species are sensitive to Gentamicin, Chloramphenicol, Azithromycin and Ciprofloxacin. They are all resistant to Trimethoprim/Sulfamethoxazole, E. coli is resistant to Doxycycline and E. faecalis has an intermediate sensitivity to Gentamicin. Overall, the Multiresistance to Antibiotics (MRA) indices obtained were above 0.2, indicating the presence of multidrug resistance in bacterial communities. The physico-chemical properties of the water varied over time and space, but on the whole remained below the threshold values of WHO guidelines. The degree of linkage between abiotic water variables and bacteriological parameters has shown that bacterial densities are more abundant in rainy seasons and increased O2 levels favor bacterial growth, while TSS, CO2 and dissolved nitrate levels affect the sensitivity of these bacteria

关键词： Bacterial Abundance Multiresistance Abiotic Aquatic

An Assessment on the Impact of Technological Addiction on Workplace Productivity: Case of the Public Sector in Zimbabwe

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World Journal of Engineering and Technology 2024年第3期12卷 635-650页

作者： Nelson Matanana Prosper Tafadzwa Denhere David Chibhoyi Allen Mutumwa Sithole Morgen noah Ariel Mutongoreni Department of Computer Science and Information Systems at Manicaland State University of Applied Sciences Mutare Zimbabwe Department of Human Resources Management at Manicaland State University of Applied Sciences Mutare Zimbabwe Department of Applied Business Sciences at Manicaland State University of Applied Sciences Mutare Zimbabwe

With the increasing integration of technology in modern workplaces, concerns have emerged regarding the addictive nature of technology and its potential consequences on employee productivity. This research aims to investigate the impact of technological addiction on workplace productivity within the public sector of Zimbabwe. The study employed a mixed-methods approach, combining surveys, interviews, and a case study analysis, to examine the prevalence and effects of technological addiction in affecting productivity in the public sector of Zimbabwe. The findings indicate that excessive use of social media, and other digital distractions is a growing concern in the public sector, leading to decreased focus, missed deadlines, and strained teamwork. Factors such as unrestricted internet access, lack of clear usage policies, and inadequate self-regulation contribute to the problem The research outcomes also highlight the need for awareness and interventions to address social media addiction in the workplace, promote healthier technology use, and uphold productivity and employee well-being.

关键词： Technology Addiction Workplace Productivity Technology Public Sector Zimbabwe

Prevalence of Hepatitis B and Associated Factors in the Garoua Central Prison, Cameroon: A Cross-Sectional Study

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Open Journal of Gastroenterology 2024年第5期14卷 174-183页

作者： Mohamadou Abdou Galdima Adamou Dodo Balkissou Guy Roger Nsenga Djapa Winnie Tatiana Bekolo Nga Gilles Aghoagni Antonin Wilson Ndjitoyap Ndam Ali Abas Mathurin Pierre Kowo Firmin Ankouane Andoulo Dominique noah noah Oudou Njoya Servais Albert Fiacre Eloumou Bagnaka Faculty of Medicine and Biomedical Sciences University of Garoua Garoua Cameroon Garoua Regional Hospital Garoua Cameroon Faculty of Medicine and Pharmaceutical Sciences University of Dschang Dschang Cameroon Faculty de Medicine and Pharmaceutical Sciences University of Douala Douala Cameroon Faculty of Health Sciences University of Buea Buea Cameroon Faculty of Medicine and Biomedical Sciences University of Yaound&#233 1 Yaound&#233 Cameroon

Introduction: Hepatitis B virus (HBV) infection is a major public health problem in Cameroon. Garoua city is the headquarters of the North Region of Cameroon, where the HBV prevalence is among the highest of the country. The aim of this study was to determine the prevalence of HBsAg carriage and associated factors among persons incarcerated in the Garoua Central Prison. Methods: It was a cross-sectional study conducted from July 1 to July 31, 2023 at the Garoua Central prison. We included all prisoners willing to participate in the study and who gave their verbal consent. We collected data using a pre-established data entry form and we used rapid test for blood screening for HBV surface antigen (HBs Ag) with ELISA confirmation. Data were analyzed using the R® software for Windows. After the univariate analysis, we selected associated variables to HBV infection with p-value p-value was set at 5%. Results: We included 1389 prisoners out of which 97.6% were male. The median age (IQR) of the study population was 28 (23 - 35) years. The median (IQR) duration of incarceration was 12 (6 - 26) months and the mean (±sd) number of incarcerations was 1.24 (±0.6). HBV prevalence was estimated at 14.8% (95% CI: 13.0 - 16.7). Upon uni- and multivariate analysis, no risk factor was significantly associated with viral hepatitis B infection in our study population. Conclusion: The prevalence of Hepatitis B was high in the Garoua Central Prison, but there were no additional risk factors for HBV infection. There is a need to include the Garoua Central Prison and by the way other prisons in the country in the chronic viral hepatitis care program.

关键词： Hepatitis B Prison Associated factors Cameroon