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Exploring emerald global geochemical provenance through fingerprinting and machine learning methods

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Artificial Intelligence in Geosciences

Artificial Intelligence in Geosciences 2024年第1期5卷 202-219页

作者： Raquel Alonso-Perez James M.d.day d.Graham Pearson Yan Luo Manuel A.Palacios Raju Sudhakar aaron Palke Earth and Planetary Science department Harvard UniversityCambridgeMA02138USA Scripps Institution of Oceanography University of California San DiegoLa JollaCA92037USA University of Alberta EdmontonABT6G 2R3Canada Eigenvector Research Inc.Manson WA98831USA Rockhurst University Kansas CityMO64110USA Gemological Institute of America CarlsbadCA92008USA

Emeralds-the green colored variety of beryl-occur as gem-quality specimens in over fifty deposits *** digital traceability methods for emerald have limitations,sample-based approaches offer robust alterna-tives,particularly for determining the geographic origin of *** factors make emerald suitable for provenance studies and hence for developing models for origin ***,the diverse elemental chemistry of emerald at minor(d trace levels(destructive techniques,including laser ablation inductively coupled plasma mass spectrometry(LA-ICP-MS),enable measurement of these diagnostic elemental ***,when applied to extensive datasets,machine learning(ML)techniques enable the creation of predictive models and statistical discrimination with adequate characterization of the *** study em-ploys a carefully selected dataset comprising more than 1000 LA-ICP-MS analyses of gem-quality emeralds,enriched with new *** dataset represents the largest available for global emerald *** con-ducted unsupervised exploratory analysis using Principal Component Analysis(PCA).For machine learning-based classification,we employed Support Vector Machine Classification(SVM-C),achieving an initial accu-racy rate of 79%.This was enhanced to 96.8%through the use of hierarchical SVM-C with PCA filters as our modeling *** ML models were trained using the concentrations of eight statistically significant ele-ments(Li,V,Cr,Fe,Sc,Ga,Rb,Cs).By leveraging high-quality LA-ICP-MS data and ML techniques,accurate identification of the geographical origin of emerald becomes *** models are important for accurate provenance of emerald,and from a geochemical perspective,for understanding the formation environments of beryl-bearing pegmatites and shales.

关键词： Beryl Provenance LA-ICP-MS Machine learning Multivariate analysis Trace elements

Temporally resolving premixed turbulent flame structures using self-supervised adversarial reconstruction of CH-PLIF

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Energy and AI 2023年第1期11卷 51-62页

作者： Ji-Hun Oh aaron W.Skiba Stephen d.Hammack Constandinos M.Mitsingas Campbell d.Carter Tonghun Lee department of Mechanical Science and Engineering University of Illinois at Urbana-ChampaignIL61801United States U.S.Air Force Research Laboratory Wright-Patterson Air Force BaseOH45433United States Army Research Lab Aberdeen Proving GroundMD21005United States

Understanding the turbulence-flame interaction is crucial to model the low-emission combustors developed for energy and propulsion applications. To this end, a novel frame interpolation (FI) method is proposed to better resolve the spatiotemporal evolution of premixed turbulent flame structures. The framework is completely selfsupervised, agnostic to optical flow, and driven by leveraging transferrable feature knowledge at lower speeds and adversarial learning to statistically map the flame dynamics across frames. The method is successfully applied on a 10 kHz CH planar laser-induced fluorescence (PLIF) dataset of highly wrinkled premixed flames with turbulent Reynolds numbers (ReT ) of 1100, 1400, and 7900, by down-sampling the image sequence to 5 kHz and restoring the sequence back to 10 kHz via FI. All reconstructions recovered important flame events and displayed excellent resemblance of the corrugated CH-layer geometries to that of the ground truths, with average intersection over union (IoU) and structural similarity index (SSIM) scores of 0.49 and 0.82, which are above the high-similarity baselines of 0.36 and 0.75, respectively. The wrinkling parameters (WP) of the flames also matched the ground truths, wherein R2 was roughly 0.95 for ReT = 1100 and 1400 and 0.85 for ReT = 7900 (lower due to the turbulence-induced uncertainties). The FI is further iteratively repeated to 40 kHz on the ReT = 7900 flames to facilitate pocket analysis by confidently linking their origin of formation, thus, enabling distinction from 3d tunnels, and improving statistical characterization of their consumption speeds. Given that the object features do not exhibit highly turbulent motions with regard to the initial time step, the proposed FI method is shown to be highly accurate and useful to analyzing finite-resolution experimental image sets including, but not restricted to, CH-PLIF.

关键词： Self-supervised frame interpolation Premixed turbulent flames Planar laser-induced fluorescence Generative adversarial networks Pocket behavior

Relating environmental variables with aquatic community structure in an agricultural/urban coldwater stream

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Ecological Processes 2021年第1期10卷 481-499页

作者： daniel T.L.Myers Richard R.Rediske James N.McNair aaron d.parke. E.Wendy Ogilvie Annis Water Resources Institute Grand Valley State University740 W Shoreline DriveMuskegonMI 49401USA. Michigan department of Environment Great Lakesand Energy525 W Allegan StreetLansingMI 48909USA. Grand Valley Metropolitan Council 678 Front Avenue NWSuite 200Grand RapidsMI 49504USA.

Background:Urban areas are often built along large rivers and surrounded by agricultural *** may lead to small tributary streams that have agricultural headwaters and urbanized lower *** study objectives assessed are as follows:(1)landscape,geomorphic,and water quality variables that best explained variation in aquatic communities and their integrity in a stream system following this agricultural-to-urban land use gradient;(2)ways this land use gradient caused aquatic communities to differ from what would be expected for an idealized natural stream or other longitudinal gradients;and(3)whether the impacts of this land use gradient on aquatic communities would grow larger in a downstream direction through the agricultural and urban *** study area was an impaired coldwater stream in Michigan,***:Many factors structured the biological communities along the agricultural-to-urban land use *** woody debris had the strongest relationship with EPT(Ephemeroptera,Plecoptera,and Trichoptera)abundance and richness and were most common in the lower,urbanized *** streambed substrate had the strongest relationship with diptera taxa and surface air breather macroinvertebrates and was dominant in agricultural *** community assemblage was influenced largely by stream flow and temperature regimes,while poor fish community integrity in lower urban reaches could be impacted by geomorphology and episodic urban pollution *** macroinvertebrates were most abundant in deforested,first-order agricultural headwaters,while EPT macroinvertebrate richness was the highest downstream of agricultural areas within the urban zone that had extensive forest ***:Environmental variables and aquatic communities would often not conform with what we would expect from an idealized natural *** richness improved downstream of agricultural *** shows promise for the recovery of aquatic systems using we

关键词： Land use Habitat Stream Fish Macroinvertebrate Gradient

Joint user association and resource partition for downlink-uplink decoupling in multi-tier HetNets

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Frontiers of Information Technology & Electronic Engineering 2017年第6期18卷 817-829页

作者： Zhi-yong FENG Ze-bing FENG T.aaron GULLIVER MOE Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications department of Electrical and Computer Engineering University of Victoria

Traditional cellular networks require the downlink (dL) and uplink (UL) of mobile users (MUs) to be associated with a single base station (BS). However, the power gap between BSs and MUs in different transmission environments results in the BS with the strongest downlink differing from the BS with the strongest uplink. In addition, the significant increase in the number of wireless machine type communication (MTC) devices accessing cellular networks has created a dL/UL traffic imbalance with higher traffic volume on the uplink. In this paper,a joint user association and resource partition framework for downlink-uplink decoupling (dUde) is developed for a tiered heterogeneous cellular network (HCN). different from the traditional association rules such as maximal received power and range extension, a coalition game based scheme is proposed for the optimal user association with dUde. The stability and convergence of this scheme are proven and shown to converge to a Nash equilibrium at a geometric rate. Moreover, the dL and UL optimal bandwidth partition for BSs is derived based on user association considering fairness. Extensive simulation results demonstrate the effectiveness of the proposed scheme,which enhances the sum rate compared with other user association strategies.

关键词： downlink-uplink decoupling User association Resource partition Heterogeneous cellular network Coalition game

An Interface-Capturing Regularization Method for Solving the Equations for Two-Fluid Mixtures

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Communications in Computational Physics 2013年第10期14卷 1322-1346页

作者： Jian du Robert d.Guy aaron L.Fogelson Grady B.Wright James P.Keener department of Mathematical Science Florida Institute of TechnologyMelbourneFL 32901USA department of Mathematics University of UtahSalt Lake CityUT 84112USA department of Bioengineering University of UtahSalt Lake CityUT 84112USA department of Mathematics University of California DavisDavisCA 95616USA department of Mathematics Boise State UniversityBoiseID 83725USA

Many problems in biology involve gels which are mixtures composed of a polymer network permeated by a fluid solvent(water).The two-fluid model is a widely used approach to described gel mechanics,in which both network and solvent coexist at each point of space and their relative abundance is described by their volume *** phase is modeled as a continuum with its own velocity and constitutive *** some biological applications,free boundaries separate regions of gel and regions of pure solvent,resulting in a degenerate network momentum equation where the network volume fraction *** overcome this difficulty,we develop a regularization method to solve the two-phase gel equations when the volume fraction of one phase goes to zero in part of the computational domain.A small and constant network volume fraction is temporarily added throughout the domain in setting up the discrete linear equations and the same set of equation is solved *** equations are very poorly conditioned for small values of the regularization parameter,but the multigrid-preconditioned GMRES method we use to solve them is efficient and produces an accurate solution of these equations for the full range of relevant regularization parameter values.

关键词： Gel swelling preconditioner two-fluid model

Pest management with biopesticides

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Frontiers of Agricultural Science and Engineering 2018年第3期5卷 295-300页

作者： James N.SEIBER Joel COATS Stephen O.dUKE aaron d.GROSS department of Environmental Toxicology University of CaliforniaDavis department of Entomology Iowa State University Natural Products Utilization Research Agricultural Research Service United States Department of AgricultureUniversityMS department of Entomology Virginia Polytechnic Institute and State University

Biopesticides are attracting interest as alternatives to conventional pesticides but without many of the non-target effects, promising a better record of safety and sustainability in pest control practices. In this article we summarize and discuss the current status and future promise of biopesticides, including how biopesticides use may increase the quality and safety of the food supply.

关键词： biopesticide GMO crops pest management

Arabidopsis FtsZ2-1 and FtsZ2-2 Are Functionally Redundant, But FtsZ-Based Plastid division Is Not Essential for Chloroplast Partitioning or Plant Growth and development

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Molecular Plant 2009年第6期2卷 1211-1222页

作者： aaron J. Schmitz Jonathan M. Glynn Bradley J.S.C. Olson Kevin d. Stokes Katherine W. Osteryoung department of Plant Biology 166 Plant Biology Bldg Michigan State University East Lansing MI 48824-1312 USA Cell and Molecular Biology Program Michigan State University East Lansing MI 48824 USA department of Energy-Plant Research Laboratory Michigan State University East Lansing MI 48824 USA Genetics Program Michigan State University East Lansing MI 48824 USA Biochemistry and Molecular Biology Program Michigan State University East Lansing MI 48824 USA Present address: The Salk Institute for Biological Studies Plant Molecular and Cellular Biology Laboratory La Jolla CA 92037 USA Present address: Mycobacteria and Brucella Section NVSL/APHIS/USDA 1920 Dayton Ave Ames IA 50010 USA

FtsZ1 and FtsZ2 are phylogenetically distinct families of FtsZ in plants that co-localize to mid-plastid rings and facilitate division of chloroplasts. In plants, altered levels of either FtsZ1 or FtsZ2 cause dose-dependent defects in chloroplast division; thus, studies on the functional relationship between FtsZgenes require careful manipulation of FtsZ levels in vivo. To define the functional relationship between the two FtsZ2 genes in Arabidopsis thaliana, FtsZ2-1 and FtsZ2-2, we expressed FtsZ2-1 in an ftsZ2-2 null mutant, and vice versa, and determined whether the chloroplast division defects were rescued in plants expressing different total levels of FtsZ2. Full rescue was observed when either the FtsZ2-1 or FtsZ2-2 level approximated total FtsZ2 levels in wild-type （WT）. Additionally, FtsZ2-2 interacts with ARC6, as shown previously for FtsZ2- 1. These data indicate that FtsZ2-1 and FtsZ2-2 are functionally redundant for chloroplast division in Arabidopsis. To rigorously validate the requirement of each FtsZ family for chloroplast division, we replaced FtsZ1 with FtsZ2 in vivo, and vice versa, while maintaining the FtsZ level in the transgenic plants equal to that of the total level in WT. Chloroplast division defects were not rescued, demonstrating conclusively that FtsZ1 and FtsZ2 are non-redundant for maintenance of WT chloroplast numbers. Finally, we generated ftsZtriple null mutants and show that plants completely devoid of FtsZ protein are viable and fertile. As plastids are presumably essential organelles, these findings suggest that an FtsZ-independent mode of plastid partitioning may occur in higher plants.

关键词： Chloroplast plastid division FtsZ ARC6 PdV1.

Errors in visual estimation of flexion contractures during total knee arthroplasty

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World Journal of Orthopedics 2013年第3期4卷 120-123页

作者： Cale A Jacobs Christian P Christensen Peter W Hester david M Burandt aaron d Sciascia Lexington Clinic LexingtonKY 40504United States

AIM: To quantify and reduce the errors in visual estimation of knee flexion contractures during total knee arthroplasty(TKA).METHOdS: This study was divided into two parts: Quantification of error and reduction of error. To quantify error, 3 orthopedic surgeons visually estimated preoperative knee flexion contractures from lateral digital images of 23 patients prior to and after surgical draping. A repeated-measure analysis of variance was used to compare the estimated angles prior to and following the placement of the surgical drapes with the true knee angle measured with a long-arm goniometer. In an effort to reduce the error of visual estimation, a dual set of inclinometers was developed to improve intraoperative measurement of knee flexion contracture during TKA. A single surgeon performed 6 knee extension measurements with the device during 146 consecutive TKA cases. Three measurements were taken with the desired tibial liner trial thickness, and 3 were taken with a trial that was 2 mm thicker. An intraclass correlation coefficient(ICC) was calculated to assess the testretest reliability for the 3 measurements taken with the desired liner thickness, and a paired t test was used to determine if the knee extension measurements differed when a thicker tibial trial liner was ***: The surgeons significantly overestimated flexion contractures in 23 TKAs prior to draping and significantly underestimated the contractures after draping(actual knee angle = 6.1°± 6.4°, pre-drape estimate = 6.9°± 6.8°, post-drape estimate = 4.3°± 6.1°, P = 0.003). Following the development and application of the measurement devices, the measurements were highly reliable(ICC = 0.98), and the device indicated that 2.7°± 2.2° of knee extension was lost with the insertion of a 2 mm thicker tibial liner. The device failed to detect a difference in knee extension angle with the insertion of the 2 mm thicker liner in 9/146 cases(6.2%).CONCLUSION: We determined the amount of error assoc

关键词： Extension Knee Arthroplasty Flexion contracture

Viral hepatitis in 2021:The challenges remaining and how we should tackle them

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World Journal of Gastroenterology 2022年第1期28卷 76-95页

作者： Rebecca dunn aaron Wetten Stuart McPherson Mhairi C donnelly Gastroenterology University Hospital of North TeesStockton on Tees TS198PEUnited Kingdom Liver Unit Freeman HospitalNewcastle NE77DNUnited Kingdom Translational and Clinical Research Institute Newcastle UniversityNewcastle NE17RUUnited Kingdom

Viral hepatitis results in 1.4 million deaths *** World Health Organization(WHO)set an ambitious target to eliminate viral hepatitis by 2030,but significant challenges *** include inequalities in access to healthcare,reaching at risk populations and providing access to screening and effective *** around viral hepatitis persists and must be *** WHO goal of global elimination by 2030 is a worthy aim,but remains ambitious and the coronavirus 2019 pandemic undoubtedly has set back *** review article will focus on hepatitis A to E,highlighting problems that have been resolved in the field over the past decade,those that remain to be resolved and suggest directions for future problem solving and research.

关键词： Hepatitis A Hepatitis B Hepatitis C Hepatitis d Hepatitis E COVId-19