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Further Analysis of Machine Tool Dimensional Accuracy and Thermal Stability under Varying Floor Temperature

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world Journal of Engineering and Technology 2024年第2期12卷 258-273页

作者： joel Arumun Shadrack Abiola Department of Control Systems and Instrumentation University of Huddersfield Huddersfield UK

Machining is as old as humanity, and changes in temperature in both the machine’s internal and external environments can be of great concern as they affect the machine’s thermal stability and, thus, the machine’s dimensional accuracy. This paper is a continuation of our earlier work, which aimed to analyze the effect of the internal temperature of a machine tool as the machine is put into operation and vary the external temperature, the machine floor temperature. Some experiments are carried out under controlled conditions to study how machine tool components get heated up and how this heating up affects the machine’s accuracy due to thermally induced deviations. Additionally, another angle is added by varying the machine floor temperature. The parameters mentioned above are explored in line with the overall thermal stability of the machine tool and its dimensional accuracy. A Robodrill CNC machine tool is used. The CNC was first soaked with thermal energy by gradually raising the machine floor temperature to a certain level before putting the machine in operation. The machine was monitored, and analytical methods were deplored to evaluate thermal stability. Secondly, the machine was run idle for some time under raised floor temperature before it was put into operation. Data was also collected and analyzed. It is observed that machine thermal stability can be achieved in several ways depending on how the above parameters are joggled. This paper, in conclusion, reinforces the idea of machine tool warm-up process in conjunction with a carefully analyzed and established machine floor temperature variation for the approximation of the machine tool’s thermally stability to map the long-time behavior of the machine tool.

关键词： Dimensional Accuracy Machine Tool Machine Floor Thermal Stability Temperature Thermal Deviation

A cross-sectional study to assess medication safety,knowledge,attitude,and practices regarding nutrition and medication among pregnant women

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Asian pacific Journal of Reproduction 2024年第3期13卷 115-119页

作者： Gauthami R Bipin Shaji Twinkle MJS krishnapriya Radhakrishnan Reshma kolar Juno Jerold joel Nitte(Deemed to be University) NGSM Institute of Pharmaceutical Sciences(NGSMIPS)Department of Pharmacy PracticeDeralakatteMangaluruIndia Nitte(Deemed to be University) KS Hegde Medical Academy(KSHEMA)Department of Obstetrics and GynaecologyDeralakatteMangaluruIndia AJ Institute of Medical Sciences and Research Centre Department of Community MedicineMangaluruKarnatakaIndia

Objective:To assess pregnant women's knowledge,attitude,and practice regarding nutrition and medication usage,analyse the prescribing pattern,and categorize them based on the Food and Drug Administration(FDA)***:A cross-sectional study was conducted with 264 pregnant women in the obstetrics and gynaecology department of a tertiary care hospital from October 2022 to August 2023.A knowledge,attitude,and practice(kAP)questionnaire was prepared in English language by the researchers and validated by an expert panel consisting of 12 *** validated questionnaire was then translated into regional languages,kannada and *** reliability of the questionnaire was assessed with test-retest method with a representative sample population of 30 subjects(10 subjects for each language).The subjects'knowledge,attitude,and practice were evaluated using the validated kAP *** safety of the medication was assessed using the FDA drug safety classification for ***:The mean scores for nutritional and medication usage knowledge,attitude,and practice were 4.14±1.15,4.50±1.09,and 3.00±1.47,*** 30 prescribed medications,3 belong to category A(no risk in human studies),8 belong to category B(no risk in animal studies),18 belong to category C(risk cannot be ruled out)and 1 drug is not classified.A significant association was observed between medication knowledge and practice(r=0.159,P=0.010).Conclusions:Most of the study population knows the need to maintain good dietary and medication practices during *** pregnant women regarding diet and medication usage is crucial in maternal care.

关键词： Pregnancy Nutrition Medication knowledge Practice Safe medication

Systematic Radio Telescope Alignment Using Portable Fringe Projection Profilometry

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Nanomanufacturing and Metrology 2024年第1期7卷 75-85页

作者： joel Berkson Justin Hyatt Nathan Julicher Byeongjoon Jeong Isaac Pimienta Rachel Ball wyatt Ellis Jason Voris Diego Torres‑Barajas Daewook kim James C.wyant College of Optical Sciences University of Arizona1630 E.University Blvd.TucsonAZ 85721USA Department of Astronomy at Steward Observatory University of Arizona933 N Cherry Ave.TucsonAZ 85721USA

In 2019,the Event Horizon Telescope(EHT)released the first-ever image of a black hole event *** are now aiming for higher angular resolutions of distant targets,like black holes,to understand more about the fundamental laws of gravity that govern our *** achieve this higher resolution and increased sensitivity,larger radio telescopes are needed to operate at higher frequencies and in larger *** like the next-generation Very Large Array(ngVLA)and the Square-kilometer Array(SkA)require building hundreds of telescopes with diameters greater than 10 ms over the next *** has a twofold *** telescope surfaces need to be more accurate to operate at higher frequencies,and the logistics involved in maintaining a radio telescope need to be simplified to support them properly in large *** of these problems can be solved with improved methods for surface metrology that are faster and more accurate with a higher *** leads to faster and more accurate panel alignment and,therefore,a more productive *** this paper,we present the use of binocular fringe projection profilometry as a solution to this problem and demonstrate it by aligning two panels on a 3-m radio telescope *** measurement takes only 10 min and directly delivers feedback on the tip,tilt,and piston of each panel to create the ideal reflector shape.

关键词： Metrology Fringe projection profilometry Off-axis alignment Radio astronomy Radio antenna

Quantum-mechanical effects in photoluminescence from thin crystalline gold films

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Light(Science & Applications) 2024年第4期13卷 783-794页

作者： Alan R.Bowman Alvaro Rodríguez Echarri Fatemeh kiani Fadil Iyikanat Ted V.Tsoulos joel D.Cox Ravishankar Sundararaman F.Javier García de Abajo Giulia Tagliabue Laboratory of Nanoscience for Energy Technologies(LNET) STIÉcole Polytechnique Fédérale de Lausanne(EPFL)LausanneSwitzerland ICFO–Institut de Ciencies Fotoniques The Barcelona Institute of Science and TechnologyCastelldefels(Barcelona)Spain. MBI–Max-Born-Institut BerlinGermany. POLIMA–Center for Polariton-driven Light–Matter Interactions University of Southern DenmarkOdense MDenmark. Danish Institute for Advanced Study University of Southern DenmarkOdense MDenmark. Department of Materials Science&Engineering Rensselaer Polytechnic InstituteTroyNYUSA. Department of Physics Applied Physicsand AstronomyRensselaer Polytechnic InstituteTroyNYUSA. ICREA–Institucio Catalana de Recerca i Estudis Avancats BarcelonaSpain

Luminescence constitutes a unique source of insight into hot carrier processes in metals,including those in plasmonic nanostructures used for sensing and energy ***,being weak in nature,metal luminescence remains poorly understood,its microscopic origin strongly debated,and its potential for unraveling nanoscale carrier dynamics largely ***,we reveal quantum-mechanical effects in the luminescence emanating from thin monocrystalline gold ***,we present experimental evidence,supported by first-principles simulations,to demonstrate its photoluminescence origin(i.e.,radiative emission from electron/hole recombination)when exciting in the interband *** model allows us to identify changes to the measured gold luminescence due to quantum-mechanical effects as the gold film thickness is ***,such effects are observable in the luminescence signal from flakes up to 40 nm in thickness,associated with the out-of-plane discreteness of the electronic band structure near the Fermi *** qualitatively reproduce the observations with first-principles modeling,thus establishing a unified description of luminescence in gold monocrystalline flakes and enabling its widespread application as a probe of carrier dynamics and light-matter interactions in this *** study paves the way for future explorations of hot carriers and charge-transfer dynamics in a multitude of material systems.

关键词： luminescence quantum crystalline

Beyond cotton and polyester: An evaluation of emerging feedstocks and conversion methods for the future of fashion industry

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Journal of Bioresources and Bioproducts 2024年第2期9卷 130-159页

作者： Ryen M.Frazier keren A.Vivas Ivana Azuaje Ramon Vera Alonzo Pifano Naycari Forfora Hasan Jameel Ericka Ford joel J.Pawlak Richard Venditti Ronalds Gonzalez Department of Forest Biomaterials North Carolina State UniversityRaleighNC 27695USA Department of Textile Engineering Chemistry and ScienceThe Nonwovens InstituteNorth Carolina State UniversityRaleighNC 27695USA

As the global population grows,the demand for textiles is increasing ***,this puts immense pressure on manufacturers to produce more *** synthetic fibers can be pro-duced cheaply,they have a negative impact on the *** the other hand,fibers from wool,sisal,fique,wood pulp(viscose),and man-made cellulose fibers(MMCFs)from cotton can-not alone meet the growing fiber demand without major stresses on land,water,and existing markets using these *** a greater emphasis on transparency and circular economy practices,there is a need to consider natural non-wood alternative sources for MMCFs to supple-ment other fiber ***,introducing new feedstocks with different compositions may require different biomass conversion ***,based on existing work,this review ad-dresses the technical feasibility of various alternative feedstocks for conversion to textile-grade ***,alternative feedstocks are introduced,and then conventional(dissolving pulp)and emerging(fibrillated cellulose and recycled material)conversion technologies are evaluated to help select the most suitable and promising processes for these emerging alternative sources of *** is important to note that for alternative feedstocks to be adopted on a meaningful scale,high biomass availability and proximity of conversion facilities are critical *** North America,soybean,wheat,rice,sorghum,and sugarcane residues are widely available and most suitable for conventional conversion through various dissolving pulp production methods(pre-hydrolysis kraft,acid sulfite,soda,SO2-ethanol-water,and potassium hydroxide)or by emerging cellulose fibrillation *** dissolving pulp conversion is well-established,fibrillated cel-lulose methods could be beneficial from cost,efficiency,and environmental ***,the authors strongly encourage more work in this growing research ***,conducting thorough cost and sustainability assessment

关键词： Non-wood Residue Regenerated cellulose Dissolving pulp Man-made cellulose fiber Apparel textile

Allying interfacial engineering of 2D carbon nanosheet-,graphene-,and graphdiyne-based heterostructured electrocatalysts toward hydrogen evolution and overall water splitting

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Electron 2024年第1期2卷 106-163页

作者： wuwei Mo joel Jie Foo wee‐Jun Ong School of Energy and Chemical Engineering Xiamen University MalaysiaSepangSelangor Darul EhsanMalaysia Center of Excellence for NaNo Energy&Catalysis Technology(CONNECT) Xiamen University MalaysiaSepangSelangor Darul EhsanMalaysia State key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamenChina Gulei Innovation Institute Xiamen UniversityZhangzhouChina Shenzhen Research Institute of Xiamen University ShenzhenChina

Electrochemical hydrogen evolution reaction(HER)and overall water splitting(OwS)for renewable energy generation have recently become a highly promising and sustainable strategy to tackle energy crisis and global warming arising from our overreliance on fossil ***,tremendous research breakthroughs have been made in 2D carbon-based heterostructured electrocatalysts in this *** heterostructures are distinguished by their remarkable electrical conductivity,exposed active sites,and mechanical ***,with fundamental mechanisms of electrocatalytic OwS summarized,our review critically emphasized on state-of-the-art 2D carbon nanosheet-,graphene-,and graphdiyne-based heterostructured electrocatalysts in HER and OwS since ***,the three emerging carbonaceous substrates tend to be incorporated with metal carbides,phosphides,dichalcogenides,nitrides,oxides,nanoparticles,single atom catalysts,or layered double ***,fascinating structural engineering and facile synthesis strategies were also unraveled to establish the structure-activity relationship,which will enlighten future electrocatalyst developments toward ameliorated HER and OwS ***,computational results from density functional theory simulations were highlighted as well to better comprehend the synergistic effects within the ***,current stages and future recommendations of this brand-new electrocatalyst type were concluded and discussed for advanced catalyst designs and future practical applications.

关键词： 2D carbon-based heterostructures electrocatalysis hydrogen evolution reaction interfacial engineering overall water splitting

The Impacts and Causes of Land Fragmentation on Farm Productivity: Case Review of East African Countries

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Open Journal of Ecology 2024年第5期14卷 455-482页

作者： Joseph Mayindo Mayele Jacob B. kolleh joel Emmanuel Saburi Department of Agricultural and Resource Economics The University of Tokyo Tokyo Japan Department of Forestry and wildlife College of Natural Resources and Environmental Studies University of Juba Juba South Sudan Department of Socio-Economic and Applied Statistics Central Agricultural Research Institute (CARI) Suakoko Liberia

This report provides an overall assessment of land fragmentation problems in East Africa. Many parts of East Africa have become highly fragmented, putting development systems and activities in these areas at risk of complete collapse. Land fragmentation occurs when land gets converted for agriculture, industrialization, or urbanization, invaded by non-local plants, or enclosed for individual use and by subdividing farmlands into subsequent smaller units called parcels with varying average farm sizes. Fragmentation results from inappropriate agricultural development processes and ineffective land use planning that fails to recognize how farmland is used, and the importance of its interconnected areas. Insecurity of tenure and resource rights are key factors in making this possible. Land fragmentation is one of the key reasons why the ability of most resources in East Africa becomes scarcer, and those remaining become “privatized” by more powerful community members—keen to maintain their access to them. Such individualistic attitudes are new and disadvantage the poorest even further by affecting the traditional customary safety nets and agricultural outputs. Neither the government nor customary governance systems effectively protect resource access for the poorest. This review summary report identifies the key causes, measures, and implications, government interventions, and the common remedies to land fragmentation problems in the East African Countries of kenya, Uganda, Rwanda, and Tanzania including neighboring Ethiopia, and the Sudan. The findings indicated from 2005 to 2015, the population kept increasing for all the named countries in East Africa with Rwanda and Uganda having a substantial increase in population density. The study review further explores the trend in the performance of agriculture by average farm sizes within the intervals of five years by highlighting their strong linkages and found that the average farm size has declined drastically, especiall

关键词： Land Fragmentation Land Consolidation Farm Productivity Industrialization Impacts Causes Average Farm Size Population East Africa

Evaluating the Impacts of Human Activities on Diversity, Abundance, and Distribution of Large Mammals in Nimule National Park, South Sudan

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Open Journal of Ecology 2024年第5期14卷 483-507页

作者： Abdallah Gordon Shazali Joseph Mayindo Mayele joel Emmanuel Saburi Jubara Nadlin Department of wildlife College of Natural Resources and Environmental Studies University of Juba Juba South Sudan Department of Environment and Natural Resources School of Forestry Environmental and Geographical Sciences College of Agricultural and Environmental Sciences Makerere University Kampala Uganda Department of Forestry College of Natural Resources and Environmental Studies University of Juba Juba South Sudan Department of Agricultural and Resource Economics The University of Tokyo Tokyo Japan

Globally, human activities have a significant impact on the diversity, abundance, and distribution of large mammals in Protected Areas (PAs). These disturbances increase human pressure on biodiversity and species habitats, highlighting the need for conservation. This study aimed to assess the abundance and distribution of large mammals in different habitat types within Nimule National Park (NNP) and understand the impacts of human activities on them. Data on the abundance and distribution of large mammals and their respective habitat types were collected through line transect surveys. Human activity signs were observed and recorded along the transect lines. To estimate the impacts of human activities on the diversity, abundance, and distribution of large mammal species, as well as to identify any significant differences between them and their habitat types, the study utilized the kruskal wallis test, Polynomial multiple regressions, and diversity indices. The findings from the Shannon-weiner and Simpson indices indicated that large mammal species were more diverse inside the park (H’ = 1.136;D = 0.570) compared to the buffer zone (H’ = 0.413;D = 0.171), with 85% (443 out of 510 samples) recorded within Nimule National Park. The species abundance showed a semi-balanced status (0.58). The diversity results among different habitat types revealed that large mammals were more diverse and highly distributed in both open woodlands (244) and dense woodlands (192), while riverine vegetation had the lowest diversity (8). Statistical tests demonstrated a highly significant difference at a 99% confidence interval (p-value = 0.01) between habitat types and identified species of large mammals. Additionally, the results highlighted the high abundance of Uganda kob (274), baboons (141), and warthog (57) across most habitat types, accounting for at least 75% of their distribution. The most prevalent human activities observed were cattle footprints (27%) and cattle dung (14%). Human

关键词： Diversity of Large Mammals Abundance and Distribution Impacts Biodiversity Conservation Human Activities Nimule National Park South Sudan

Combination Activity of Standard Antituberculosis Drugs and Extracts of Medicinal Plants Commonly Used in Traditional Treatment of Tuberculosis in Uganda

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Advances in Infectious Diseases 2024年第3期14卷 511-522页

作者： Moses Mpeirwe kevin komakech Duncan Ssesazi Patrick Engeu Ogwang joel Bazira Department of Microbiology Mbarara University of Science and Technology Mbarara Uganda Department of Medical Microbiology Mycobacteriology (BSL-3) Laboratory Makerere University Kampala Uganda Department of Pharmaceutical Sciences Mbarara University of Science and Technology Mbarara Uganda Department of Pharmacy Mbarara University of Science and Technology Mbarara Uganda

Introduction: Resistance to antituberculosis drugs and adverse drug reactions remain the leading causes of tuberculosis therapeutic failure globally. Despite the increasing acceptance of medicinal plant use in combination with conventional antituberculosis drugs in treatment of tuberculosis (TB) in Uganda, there is paucity of knowledge on their combination effect. Aim: This research aimed to determine combination activity of standard antituberculosis drugs with extracts of Zanthoxylum leprieurii Guill. & Perr. and Rubia cordifolia L., the two common antituberculosis medicinal plants in Uganda, against pansensitive (H37Rv) and multi-drug resistant (MDR) Mycobacterium tuberculosis strains. Materials and Methods: Two reference MTB strains (H37Rv and MDR strain) were inoculated on Middlebrook 7H11 medium containing a combination of standard antituberculosis drugs and methanol extracts of Z. leprieurii and R. cordifolia at varying concentrations. The number of colonies on the plates was observed and counted weekly for up to 8 weeks. In vitro combination activity was determined using proportion method. Mean percentage inhibition was calculated for the reduction of number of colonies on drug-extract combination medium in relation to drug-extract-free control medium. Results: Drug-extract combinations showed good combination activity against Mycobacterium tuberculosis strains when compared with individual standard anti-TB drugs. This was more exhibited against MDR strain. There was however a reduction in percentage inhibition when extracts were combined with ethambutol and streptomycin against H37Rv strain. Conclusions: Zanthoxylum leprieurii and Rubia cordifolia in combination with standard anti-TB drugs exhibited increased in vitro activity against Mycobacterium tuberculosis, especially MDR-TB strain. This justifies the local use of these plants in traditional treatment of tuberculosis especially in resistant cases in Uganda.

关键词： Combination Activity Medicinal Plants Zanthoxylum leprieurii Rubia cordifolia Standard Antituberculosis Drugs