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Frontiers of Structural and Civil Engineering 2024年第8期18卷 1195-1208页

作者： Dev Kunwar Singh CHAUHAN Pandu r.VUNDAVILLI Indian Institute of Technology Bhubaneswar Bhubaneswar 752050India

The present work aims to develop an object tracking controller for the Stewart platform using a computer vision-assisted machine learning-based *** research is divided into two *** first module focuses on the design of a motion controller for the Physik Instrumente(PI)-based Stewart *** contrast,the second module deals with the development of a machine-learning-based spatial object tracking algorithm by collecting information from the Zed 2 stereo vision ***,simple feed-forward neural networks(NN)are used to predict the orientation of the top table of the *** training,the x,y,and z coordinates of the three-dimensional(3D)object,extracted from images,are used as the input to the *** contrast,the orientation information of the platform(that is,rotation about the x,y,and z-axes)is considered as the output from the *** orientation information obtained from the network is fed to the inverse kinematics-based motion controller(module 1)to move the platform while tracking the *** training,the optimised NN is used to track the continuously moving 3D *** experimental results show that the developed NN-based controller has successfully tracked the moving spatial object with reasonably good accuracy.

关键词： Stewart platform feed-forward neural networks motion controller inverse kinematics stereo vision

Soil security and global food security

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 297-302页

作者： David r.MONTGOMErY Department of Earth and Space Sciences University of Washington townSeattleWA 98105USA

Over the course of the postglacial period has managed to add degrade a substantial portion of the world's potential agricultural land. The soil loss and degradation that has repeatedly impacted regional societies around the world resulted from agricultural practices that increased the physical loss of soil(erosion), reduced soil organic matter, changed p H(acidification) or salinity,and disrupted or altered communities of soil life. In the coming century, as continued soil degradation threatens global food security while the global population keeps rising it is imperative that farmers develop and adopt soilhealth building(regenerative) practices to solve a problem that has plagued societies throughout history. Growing evidence suggests that agricultural systems that combine cover crops, reduced tillage, and diverse crop rotations can reduce erosion, enhance soil health and rebuild soil organic matter to cultivate beneficial soil life and harvest both economic and environmental benefits. In the coming post-oil world, global food security would benefit from a global effort to promote soil restoration to help addresses the challenge of sustainably feeding the world, increase soil-based carbon sequestration,protect on-farm biodiversity and reduce off-farm water pollution. Because soil security sets a solid foundation for global food security, agricultural policies and subsidies should be reformed to encourage farmers to adopt regenerative,soil-building practices.

关键词： Agriculture soil security food security regenerative

Control of visible‑range transmission and refection haze by varying pattern size,shape and depth in fexible metasurfaces

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Frontiers of Optoelectronics 2024年第3期17卷 51-68页

作者： Avijit Maity Vaswati Biswas r.Vijaya Department of Physics Indian Institute of Technology KanpurKanpur 208016India Centre for Lasers and Photonics Indian Institute of Technology KanpurKanpur 208016India

Cost-efective soft imprint lithography technique is used to prepare fexible thin polymeric surfaces containing a periodic arrangement of nanodimples and nanobumps of sub-micron *** a single master mold of self-assembled colloidal crystal,metasurfaces with diferent depths and heights of patterns with a fxed pitch are possible,which makes the process inexpensive and *** metasurfaces are studied for their difuse and total transmission and refection spectra in the visible *** transmission haze and refection haze are calculated from the *** surface containing nanobumps of lesser pattern height result in higher values of refection and transmission haze than from surfaces containing nanodimples of much higher depth for the same *** haze is more dependent on the pattern depth or height and less dependent on the pitch of the ***-feld transmission profles measured in the same wavelength range from the patterned surfaces show that the scattering increases with the increase of the ratio of pattern depth/height to pitch,similar to the haze measurements conducted with a closed integrating *** profles show that the angular spread of scattered light in transmission is within 10°,explaining the reason for the relatively low transmission haze in all the patterned *** results confrm that the nanobump pattern gives higher transmission haze compared to nanodimple *** controlling the ratio of pattern depth/height to pitch of the features on these surfaces,both an increase in optical haze and a balance between total refection intensity and total transmission intensity can be achieved.

关键词： Metasurface refection haze Transmission haze Soft imprint lithography

rodent biology and ecologically based rodent management(EBrM)-25 years of progress through promoting multidisciplinary research

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Integrative Zoology 2024年第1期19卷 2-7页

作者： Grant r. SINGLETON Lyn A. HINDS rhodes MAKUNDI Steven r. BELMAIN Natural resources Institute University of Greenwich Kent UK CSIrO Health and Biosecurity Canberra ACT Australia African Centre of Excellence for Innovative rodent Pest Management and Biosensor Technology Development Sokoine University of Agriculture Morogoro Tanzania Institute of Pest Management Sokoine University of Agriculture Morogoro Tanzania

“During rodent outbreak years in eastern Africa,lo-cally,more than 80%of the potential harvest may be lost,but even in non-outbreak periods,rodents cause chronic damage to crops….The pest rodent story in Africa in-volves several species embedded in a broad and variable landscape with highly variable densities.”(Leirs et al.2010).

关键词： damage crops

Basis for the diversity and extent in loss of digestible nutrients created by dietary phytin: Emphasis on fowl and swine

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动物营养学报 2024年第1期16卷 422-428页

作者： Edwin T. Moran Michael r. Bedford Poultry Science Department Auburn University AL 36830-5416 USA AB Vista Woodstock Court Blenheim Road Marlborough Wiltshire SN8 4AN UK

Phytin is the Ca 2+ -Mg 2+ -K + salt of phytic acid that is created and deposited in the aleurone layer and/or germ of grains and legumes. Its high presence in feedstuffs for fowl and swine diets results in it being a universal and significant impediment to optimum performance. Phytin impairs gastrointestinal recovery of a wide array of nutrients, the effect varying with the nutrient concerned. On exposure to low pH during gastric digestion, phytin dissociates into phytic acid and solubilized Ca 2+ . Even at low gastric pH, phytic acid is negatively charged which forms the basis of its anti-nutritive behavior. Pepsinogen has extensive basic amino acids on its activation peptide that are presented as cations at low pH which are targeted by pepsin for activation. Partially crystalized Ca 2+ near the enzyme's active site further stabilizes its newly formed structure. Thus, phytic acid appears to interfere with gastric digestion by several mechanisms; interfering with pepsinogen activation by binding to the polypeptide's basic amino acids; coordinating free Ca 2+ , destabilizing pepsin; binding some dietary proteins directly, further compromising gastric proteolysis. Upon digesta attaining neutrality in the duodenum, Ca 2+ and other cations re-bind with accessible anions, phytic acid being a significant contender. Phytate not only binds free cations but can also strip them from enzymes (e.g. Ca 2+ , Zn 2+ ) which reduces their structural resistance to autolysis and ability as co-factors (e.g. Zn 2+ ) to increase enzyme activity. Goblet cells initially employ Ca 2+ as an electronic shield between mucin layers enabling granule formation and cell storage. After mucin granule release, Ca 2+ is progressively displaced by Na + to free the viscous mucins enabling its translocation. Mucin entangles with the glycocalyx of adjacent enterocytes thereby constructing the unstirred water layer (USWL). Excessive removal of Ca 2+ from mucin by phytic acid increases its fluidity facilit

关键词： Digestive enzyme Calcium Endogenous protein Mucin Phytin

Influence of B4C and ZrB2 reinforcements on microstructural,mechanical and wear behaviour of AA 2014 aluminium matrix hybrid composites

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Defence Technology（防务技术） 2024年第10期40卷 242-254页

作者： ramesh Babu r rajendran C Saiyathibrahim A rajkumar Velu Department of Mechanical Engineering Karpagam Institute of TechnologyCoimbatore 641105India Department of Mechanical Engineering Sri Krishna College of Engineering and TechnologyCoimbatore 641008India Department of Mechanical Engineering Indian Institute of Technology JammuJammu and Kashmir 181221India

Considering their affordability and high strength-to-weight ratio,lightweight aluminium alloys are the subject of intensive research aimed at improving their properties for use in the aerospace *** research effort aims to develop novel hybrid composites based on AA 2014 alloy through the use of liquid metallurgy stir casting to reinforce dual ceramic particles of Zirconium Diboride(ZrB_(2))and Boron Carbide(B4C).The weight percentage(wt%)of ZrB_(2) was varied(0,5,10,and 15),while a constant 5 wt%of B4C was maintained during this *** as-cast samples have been assessed using an Optical Microscope(OM)and a Scanning Electron Microscope(SEM)with Energy Dispersive Spectroscopy(EDS).The properties such as hardness,tensile strength,and wear characteristics of stir cast specimens were assessed to examine the impact of varying weight percentages of reinforcements in AA 2014 *** particular,dry sliding wear behaviour was evaluated considering varied loads using a pin-on-disc *** the weight%of ZrB_(2) grew and B4C was incorporated,hybrid composites showed higher hardness,tensile strength,and wear ***,the incorporation of a cumulative reinforcement consisting of 15 wt%ZrB_(2) and 5 wt%B4C resulted in a significant 31.86%increase in hardness and a 44.1%increase in tensile strength compared to AA 2014 *** addition,it has been detected that wear resistance of hybrid composite pin(containing 20 wt%cumulative reinforcement)is higher than that of other stir cast wear test pins during the whole range of applied *** surfaces of tensile specimens showed ductile fracture in the AA 2014 matrix and mixed mode for hybrid *** surfaces obtained employing higher applied load indicated abrasive wear with little plastic deformation for hybrid composites and dominant adhesive wear for matrix ***,the superior mechanical and tribological performance of hybrid composites can be attributed to dual reinforcement pa

关键词： AA 2014 alloy Stir casting Hybrid composite Hardness Tensile strength Specific wear rate

Features of effective feedback

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Annals of Eye Science 2024年第3期9卷 2-7页

作者： Ilhem Mili Sonia Trabelsi Sonia Mezigh Manel Mokrani karl Golnik Mejdi Boukari Faculty of Medicine of Tunis University of Tunis El ManarTunisTunisia Department of Ophthalmology Charles Nicolle University Hospital of TunisTunisTunisia Barrow Neurological Institute PhoenixAZUSA

Effective feedback is an essential part of completing and succeeding in *** is a significant aid to the training of professionals and is increasingly becoming an integral part of any *** purpose of this document is to describe the characteristics of good *** pedagogical concept of feedback requires it to be non-judgmental and as neutral as *** is“specific information that compares the learner’s observed performance to a given standard to improve their future performance”.Understanding the difference between summative evaluation and feedback is *** evaluation is based on judgment and a final decision of success or failure,feedback is a positive and constructive action *** feedback,the learner will understand if they have achieved their learning goals and how they can achieve *** role of the teacher is to provide explicit and meaningful information,identify specific areas for improvement,and provide appropriate strategies to achieve this,focusing on the learner’s performance and not on the *** six characteristics of feedback include source,connotation,focus level,number of feedback,timing,and *** key points of a successful feedback session depend on three main areas:structure,format,and ***,the use of feedback is essential to the learner autonomy and has a major impact on their learning,behaviors,and *** stated,constructive and regular feedback leads changes that are perceived as positive and,in addition,increases the level of engagement of individuals in the *** curriculum should include systematic feedback for every learning session.

关键词： Feedback evaluation assessment learning self-regulation

Mantle avalanches in a Venus-like stagnant lid planet

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Earth and Planetary Physics 2024年第5期8卷 686-702页

作者： Madeleine C.Kerr Dave r.Stegman Institute of Geophysics and Planetary Physics Scripps Institution of Oceanography University of California

Stagnant lid planets are characterized by a globe-encircling, conducting lid that is thick and strong, which leads to reduced global surface heat flows. Consequently, the mantles of such planets can have warmer interiors than Earth, and interestingly, a pyrolitic mantle composition under warmer conditions is predicted to have a distinctly different mantle transition zone compared to the present-day Earth(Hirose, 2002; Stixrude and Lithgow-Bertelloni, 2011; Ichikawa et al., 2014; Dannberg et al, 2022). Instead of olivine primarily transforming into its higher-pressure polymorphs such as wadsleyite and then ringwoodite, at pressures corresponding to410 km and 520 km depth in Earth, respectively, it instead transforms into a mineral assemblage of wadsleyite, majorite, and ferropericlase(WMF), and then to majorite + ferropericlase(MF), before finally transforming into bridgmanite at pressures corresponding to 660 km depth in Earth(Stixrude and Lithgow-Bertelloni, 2011; Ichikawa et al., 2014). Convective motions in stagnant lid planets are dominated by small-scale instabilities(cold drips) forming within the mobile rheological sublayer under the rigid lid. Using ASPECT and a thermodynamic model of a pyrolitic mantle composition generated by HeFESTo, we show that under certain conditions, the small drips can pond atop the WMF-MF mineral phase transition. The barrier to convective flow arises from the WMF mineral phase assemblage having an effective negative thermal expansivity(Stixrude and Lithgow-Bertelloni, 2022). Although large-scale downwellings that typically occur within mobile lid planets are able to pass through the WMF zone without difficulty(Dannberg et al., 2022; Li rP et al.,2024), the smaller and less negatively buoyant nature of downwelling drips in stagnant lid planets are more susceptible to these effects,which leads to an ephemeral layering of the mantle. Our numerical models show that in stagnant lid planets with mantle potential temperatures that exceed

关键词： Venus mantle avalanches numerical modelling phase transitions

Structural changes in the obese brain

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Neural regeneration research 2024年第12期19卷 2561-2562页

作者： Anna r.r.Da Conceicao Marcelo N.N.Vieira Fernanda G.De Felice D’Or Institute for research and Education Rio de JaneiroBrazil Institute of Medical Biochemistry Leopoldo De Meis Federal University of Rio de JaneiroRio de JaneiroBrazil Centre for Neuroscience Studies Department of Biomedical and Molecular Sciences&Department of PsychiatryQueen’s UniversityKingstonONCanada

Obesity represents a major global health concern,with widespread growing prevalence and severe consequences for the quality of life and life expectancy of affected individuals and for the economic burden of healthcare systems(Prospective Studies Collaboration,2009).Obesity is a well-established risk factor for a variety of conditions including metabolic,vascula r,and heart diseases,and seve ral types of cancer(Prospective Studies Collaboration,2009).

关键词： diseases consequences prevalence

Electro-optic tuning in composite silicon photonics based on ferroionic 2D materials

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Light(Science & Applications) 2024年第5期13卷 852-864页

作者： Ghada Dushaq Solomon Serunjogi Srinivasa r.Tamalampudi Mahmoud rasras Department of Electrical and Computer Engineering New York University Abu DhabiP.O.Box 129188Abu DhabiUnited Arab Emirates NYU Tandon School of Engineering New York UniversityNew YorkNYUSA

Tunable optical materials are indispensable elements in modern optoelectronics,especially in integrated photonics circuits where precise control over the effective refractive index is essential for diverse ***-dimensional materials like transition metal dichalcogenides(TMDs)and graphene exhibit remarkable optical responses to external ***,achieving distinctive modulation across short-wave infrared(SWIr)regions while enabling precise phase control at low signal loss within a compact footprint remains an ongoing *** this work,we unveil the robust electro-refractive response of multilayer ferroionic two-dimensional CuCrP2S6(CCPS)in the near-infrared wavelength *** integrating CCPS into silicon photonics(SiPh)microring resonators(Mrr),we enhance lightmatter interaction and measurement sensitivity to minute phase and absorption *** show that electrically driven Cu ions can tune the effective refractive index on the order of 2.8×10−3 rIU(refractive index unit)while preserving extinction ratios and resonance ***,these devices exhibit low optical losses and excellent modulation efficiency of 0.25 *** with a consistent blue shift in the resonance wavelengths among all devices for either polarity of the applied *** results outperform earlier findings on phase shifters based on ***,our study demonstrates distinct variations in electro-optic tuning sensitivity when comparing transverse electric(TE)and transverse magnetic(TM)modes,revealing a polarization-dependent response that paves the way for diverse applications in light *** combined optoelectronic and ionotronic capabilities of two-terminal CCPS devices present extensive opportunities across several *** potential applications range from phased arrays and optical switching to their use in environmental sensing and metrology,optical imaging systems,and neuromorphic systems in light-sensitive artificial synapses.

关键词： tuning polarization refractive