Levitation by a dipole electric field

The phenomenon of floating can be fascinating in any field, with its presence seen in art, films, and scientific research. This phenomenon is a captivating and pertinent subject with practical applications, such as Penning traps for antimatter confinement and Ion traps as essential architectures for quantum computing models. In our project, we reproduced the 1893 water bridge experiment using glycerol and first observed that lump-like macroscopic dipole moments can undergo near-periodic oscillations that exhibit floating effects and do not need classical bridge form. By combining experimental analysis, neural networks, investigation of Kelvin force generated by the Finite element method, and exploration of discharging, we gain insights into the mechanisms of motion. Our discovery has overturned the previous impression of a bridge floating in the water, leading to a deeper understanding of the new trap mechanism under strong electric fields with a single pair of electrodes.Comment: 5 pages, 5 figure

Early iron production in the Levant: Smelting and smithing at early 1st millennium BC Tell Hammeh, Jordan, and Tel Beth-Shemesh, Israel

The use of iron in the Near East is first attested by the sporadic occurrence of iron artefacts during the Bronze Age. By the end of the Late Bronze Age, however, use of iron metal gradually increases to such a level that one can assume a reasonably regular production of iron metal from terrestrial ores by smelting. However, very few iron metallurgical workshops or installations have been discovered in the Near East thus far. Of these, most are apparently related to secondary smithing, and very few if any have clear evidence for iron smelting. Recent fieldwork at Tell Hammeh, Jordan, identified a major iron smelting operation dated to ca. 930 Cal BC. Excavations in 2001 and 2003 at Tel Beth- Shemesh, Israel, uncovered remains of a full-scale smithing operation, dating to ca. 900 Cal BC. Dedicated excavation techniques were developed and refined for both sites, aiming at optimal recovery of both technological and archaeological information. The excavated materials were comprehensively analysed using relevant scientific analytical techniques, which included the development and application of a calibration method for quantitative bulk chemical analysis of iron- rich materials by XRF. Combining laboratory data and fieldwork, this thesis explores the particular lime- rich and iron-oxide-poor nature of the Hammeh slags as a function of the composition of the local ore and the sacrificial contribution of technical ceramics (tuyeres and furnace wall). Furthermore, it compares the smelting operations at Tell Hammeh with the smithing at Tel Beth-Shemesh, both in terms of their respective archaeological contexts as well as of their technological residues. This aims at the identification and reconstruction of the chaine operatoire of the technologies at both sites. The reconstructed technological processes are discussed in terms of their place in the socio-economic and cultural context of the early first millennium BC of the Levant. Beyond providing new data about early iron metallurgy, the integrated archaeological and laboratory approach, the excavation methods applied, the analytical methodology, as well as the archaeometric data presented here may serve as a model for the excavation, interpretation, or comparison of future (and previous) discoveries of iron metallurgy in the Near East

An approach to the diagnosis of lumbar disc herniation using deep learning models

Background: In magnetic resonance imaging (MRI), lumbar disc herniation (LDH) detection is challenging due to the various shapes, sizes, angles, and regions associated with bulges, protrusions, extrusions, and sequestrations. Lumbar abnormalities in MRI can be detected automatically by using deep learning methods. As deep learning models gain recognition, they may assist in diagnosing LDH with MRI images and provide initial interpretation in clinical settings. YOU ONLY LOOK ONCE (YOLO) model series are often used to train deep learning algorithms for real-time biomedical image detection and prediction. This study aims to confirm which YOLO models (YOLOv5, YOLOv6, and YOLOv7) perform well in detecting LDH in different regions of the lumbar intervertebral disc.Materials and methods: The methodology involves several steps, including converting DICOM images to JPEG, reviewing and selecting MRI slices for labeling and augmentation using ROBOFLOW, and constructing YOLOv5x, YOLOv6, and YOLOv7 models based on the dataset. The training dataset was combined with the radiologist’s labeling and annotation, and then the deep learning models were trained using the training/validation dataset.Results: Our result showed that the 550-dataset with augmentation (AUG) or without augmentation (non-AUG) in YOLOv5x generates satisfactory training performance in LDH detection. The AUG dataset overall performance provides slightly higher accuracy than the non-AUG. YOLOv5x showed the highest performance with 89.30% mAP compared to YOLOv6, and YOLOv7. Also, YOLOv5x in non-AUG dataset showed the balance LDH region detections in L2-L3, L3-L4, L4-L5, and L5-S1 with above 90%. And this illustrates the competitiveness of using non-AUG dataset to detect LDH.Conclusion: Using YOLOv5x and the 550 augmented dataset, LDH can be detected with promising both in non-AUG and AUG dataset. By utilizing the most appropriate YOLO model, clinicians have a greater chance of diagnosing LDH early and preventing adverse effects for their patients

Dealloyed Pt_(2)Os nanoparticles for enhanced oxygen reduction reaction in acidic electrolytes

Carbon-supported Pt2Os (Pt_(2)Os/C) nanoparticles in 3.55 nm sizes are synthesized from a wet chemical reflux process. Subsequently, the Pt_(2)Os/C undergoes a dealloying treatment in which multiple cyclic voltammetric scans are imposed to dissolve the Os atoms selectively from the surface of the Pt_(2)Os nanoparticles. X-ray diffraction signals from the dealloyed sample (DA–Pt_(2)Os/C) indicate a fcc phase and composition analysis suggests Pt4Os. Line scans from the scanning transmission electron microscope confirm that the surface of Pt_(4)Os is depleted with the Os atoms. This agrees with our quantum mechanics (Density Funtional theory) calculations, which predict for the Pt_(3)Os composition that the surface skin layer is pure Pt. The DA–Pt_(2)Os/C shows impressive electrocatalytic behaviors (0.29 mA μgPt^(−1) in mass activity and 1.03 mA cmPt^(−2) in specific activity) for the oxygen reduction reaction (ORR) in oxygen-saturated 0.1 M aqueous HClO_4 solution, as compared to those of commercially available Pt/C and as-synthesized Pt_(2)Os/C. In stability test, the DA–Pt_(2)Os/C demonstrates a better retention of ORR activities and a smaller loss of electrochemical active surface area. We verify experimentally that a four-electron step is responsible for the ORR process occurring on the DA–Pt_(2)Os/C

Wolfberry genomes and the evolution of Lycium (Solanaceae)

AbstractWolfberry Lycium, an economically important genus of the Solanaceae family, contains approximately 80 species and shows a fragmented distribution pattern among the Northern and Southern Hemispheres. Although several herbaceous species of Solanaceae have been subjected to genome sequencing, thus far, no genome sequences of woody representatives have been available. Here, we sequenced the genomes of 13 perennial woody species of Lycium, with a focus on Lycium barbarum. Integration with other genomes provides clear evidence supporting a whole-genome triplication (WGT) event shared by all hitherto sequenced solanaceous plants, which occurred shortly after the divergence of Solanaceae and Convolvulaceae. We identified new gene families and gene family expansions and contractions that first appeared in Solanaceae. Based on the identification of self-incompatibility related-gene families, we inferred that hybridization hotspots are enriched for genes that might be functioning in gametophytic self-incompatibility pathways in wolfberry. Extremely low expression of LOCULE NUBER (LC) and COLORLESS NON-RIPENING (CNR) orthologous genes during Lycium fruit development and ripening processes suggests functional diversification of these two genes between Lycium and tomato. The existence of additional flowering locus C-like MADS-box genes might correlate with the perennial flowering cycle of Lycium. Differential gene expression involved in the lignin biosynthetic pathway between Lycium and tomato likely illustrates woody and herbaceous differentiation. We also provide evidence that Lycium migrated from Africa into Asia, and subsequently from Asia into North America. Our results provide functional insights into Solanaceae origins, evolution and diversification.</jats:p

Partonic flow and ϕ\phi-meson production in Au+Au collisions at sNN\sqrt{s_{NN}} = 200 GeV

We present first measurements of the $\phi$-meson elliptic flow ($v_{2}(p_{T})$) and high statistics $p_{T}$ distributions for different centralities from $\sqrt{s_{NN}}$ = 200 GeV Au+Au collisions at RHIC. In minimum bias collisions the $v_{2}$ of the $\phi$ meson is consistent with the trend observed for mesons. The ratio of the yields of the $\Omega$ to those of the $\phi$ as a function of transverse momentum is consistent with a model based on the recombination of thermal $s$ quarks up to $p_{T}\sim 4$ GeV/$c$, but disagrees at higher momenta. The nuclear modification factor ($R_{CP}$) of $\phi$ follows the trend observed in the $K^{0}_{S}$ mesons rather than in $\Lambda$ baryons, supporting baryon-meson scaling. Since $\phi$-mesons are made via coalescence of seemingly thermalized $s$ quarks in central Au+Au collisions, the observations imply hot and dense matter with partonic collectivity has been formed at RHIC.Comment: 6 pages, 4 figures, submit to PR

Measurement of Transverse Single-Spin Asymmetries for Di-Jet Production in Proton-Proton Collisions at s=200\sqrt{s} = 200 GeV

We report the first measurement of the opening angle distribution between pairs of jets produced in high-energy collisions of transversely polarized protons. The measurement probes (Sivers) correlations between the transverse spin orientation of a proton and the transverse momentum directions of its partons. With both beams polarized, the wide pseudorapidity ($-1 \leq \eta \leq +2$) coverage for jets permits separation of Sivers functions for the valence and sea regions. The resulting asymmetries are all consistent with zero and considerably smaller than Sivers effects observed in semi-inclusive deep inelastic scattering (SIDIS). We discuss theoretical attempts to reconcile the new results with the sizable transverse spin effects seen in SIDIS and forward hadron production in pp collisions.Comment: 6 pages total, 1 Latex file, 3 PS files with figure

Longitudinal double-spin asymmetry for inclusive jet production in p+p collisions at sqrt(s)=200 GeV

We report a new STAR measurement of the longitudinal double-spin asymmetry A_LL for inclusive jet production at mid-rapidity in polarized p+p collisions at a center-of-mass energy of sqrt(s) = 200 GeV. The data, which cover jet transverse momenta 5 < p_T < 30 GeV/c, are substantially more precise than previous measurements. They provide significant new constraints on the gluon spin contribution to the nucleon spin through the comparison to predictions derived from one global fit of polarized deep-inelastic scattering measurements.Comment: 7 pages, 4 figures + 1 tabl

Enhanced strange baryon production in Au+Au collisions compared to p+p at sqrts = 200 GeV

We report on the observed differences in production rates of strange and multi-strange baryons in Au+Au collisions at sqrts = 200 GeV compared to pp interactions at the same energy. The strange baryon yields in Au+Au collisions, then scaled down by the number of participating nucleons, are enhanced relative to those measured in pp reactions. The enhancement observed increases with the strangeness content of the baryon, and increases for all strange baryons with collision centrality. The enhancement is qualitatively similar to that observed at lower collision energy sqrts =17.3 GeV. The previous observations are for the bulk production, while at intermediate pT, 1 < pT< 4 GeV/c, the strange baryons even exceed binary scaling from pp yields.Comment: 7 pages, 4 figures. Printed in PR

Forward Neutral Pion Transverse Single Spin Asymmetries in p+p Collisions at \sqrt{s}=200 GeV

We report precision measurements of the Feynman-x dependence, and first measurements of the transverse momentum dependence, of transverse single spin asymmetries for the production of \pi^0 mesons from polarized proton collisions at \sqrt{s}=200 GeV. The x_F dependence of the results is in fair agreement with perturbative QCD model calculations that identify orbital motion of quarks and gluons within the proton as the origin of the spin effects. Results for the p_T dependence at fixed x_F are not consistent with pQCD-based calculations.Comment: 6 pages, 4 figure