Holes Localized on a Skyrmion in a Doped Antiferromagnet on the Honeycomb Lattice: Symmetry Analysis

Using the low-energy effective field theory for hole-doped antiferromagnets on the honeycomb lattice, we study the localization of holes on Skyrmions, as a potential mechanism for the preformation of Cooper pairs. In contrast to the square lattice case, for the standard radial profile of the Skyrmion on the honeycomb lattice, only holes residing in one of the two hole pockets can get localized. This differs qualitatively from hole pairs bound by magnon exchange, which is most attractive between holes residing in different momentum space pockets. On the honeycomb lattice, magnon exchange unambiguously leads to $f$-wave pairing, which is also observed experimentally. Using the collective-mode quantization of the Skyrmion, we determine the quantum numbers of the localized hole pairs. Again, $f$-wave symmetry is possible, but other competing pairing symmetries cannot be ruled out.Comment: 41 pages, 4 figure

Expression and inhibition of MBD2 in gastric cancer

ABSTRACT: As gastric cancer (GC) involves changes in gene expression, proteins that bind to methylated DNA, such as methyl-CpG-binding domain protein 2 (MBD2) may be a potential target for cancer treatment. We used immunohistochemistry and immunofluorescence to detect the MBD2 expression in GC tissues and SGC-7901 (GC cell line), RT-PCR and western blotting to evaluate the knockdown of MBD2 by specific siRNAs, and MTT assay to analyse the proliferation of SGC-7901 after the MBD2-siRNA transfection. We found GC expression of MBD2 protein was higher than in matched non-cancerous tissues, and the MBD2 expression was associated with the size and histological grade of GC tissues. MBD2 protein was distributed in the nucleus of GC cells, and the MBD2 mRNA and protein could be inhibited by a specific siRNA. Finally, after 96 h of the MBD2-siRNA transfection, the growth rate of SGC-7901 decreased compared with controls. Hence MBD2 may be an underlying target of gastric cancer treatment

9,000-year-old barley consumption in the foothills of central Asia

Scholars are increasingly favoring models for the origins of agriculture that involve a protracted process of increasing interdependence within a series of mutualistic relationships between humans and plants, as opposed to a rapid single event or innovation. Nonetheless, these scholars continue to debate over when people first started foraging for grass seeds, when they began to readily utilize sickles, how prominent the early selection pressures were, and when the first traits of domestication fully introgressed into the cultivated grass population. Here, we present complementary archaeobotanical and archaeological (stone tool) evidence for cereal foragers from Toda-1 Cave in the Surkhan Darya, dating to 9200 cal BP. We conclude that early Holocene foragers were processing grains along with nuts and fruits as far north as the rich river valleys of southern Uzbekistan. These data expand the known range that preagricultural cereal foragers covered in the early Holocene, adding to our understanding of the cultural processes that led to farming. Additionally, we present the earliest evidence for people interacting with the progenitors for pistachios and apples (or a close apple relative). The complex foraging behaviors that led to cultivation were being undertaken by people during the early Holocene across a wider area of Eurasia than previously thought.Results Discussion Materials and Methods Excavations. Radiocarbon Chronology. Microbotanical Remains. Macrobotanical Remains. Geochemical Analysis. Data, Materials, and Software Availability

Modeling of polydispersed bubbly flow in continuous casting mold using multiple-size-group model

A population balance model based on the Multiple-Size-Group (MUSIG) approach has been developed to investigate the polydispersed bubbly flow inside a slab continuous casting mold. The Eulerian-Eulerian approach is used to describe the motion of the two-phase flow. Sato and Sekiguchi model is used to account for the bubble induced turbulence. Luo and Svendsen model and Prince and Blanch model are used to describe the bubbles breakup and coalescence behavior respectively. A 1/4rd water model of the slab continuous casting mold were applied to investigate the bubble distribution. Against experimental data, numerical results show good agreement for the gas volume fraction and local bubble Sauter mean diameter. The bubble Sauter mean diameter in the upper recirculation zone decreases with increasing water flow rate and increases with increasing gas flow rate. Close agreements between the predictions and measurements demonstrates the capability of the MUSIG model in modeling bubbly flow inside the continuous casting mold

Modeling of polydispersed bubbly flow in continuous casting mold using multiple-size-group model

A population balance model based on the Multiple-Size-Group (MUSIG) approach has been developed to investigate the polydispersed bubbly flow inside a slab continuous casting mold. The Eulerian-Eulerian approach is used to describe the motion of the two-phase flow. Sato and Sekiguchi model is used to account for the bubble induced turbulence. Luo and Svendsen model and Prince and Blanch model are used to describe the bubbles breakup and coalescence behavior respectively. A 1/4rd water model of the slab continuous casting mold were applied to investigate the bubble distribution. Against experimental data, numerical results show good agreement for the gas volume fraction and local bubble Sauter mean diameter. The bubble Sauter mean diameter in the upper recirculation zone decreases with increasing water flow rate and increases with increasing gas flow rate. Close agreements between the predictions and measurements demonstrates the capability of the MUSIG model in modeling bubbly flow inside the continuous casting mold

"Comparison of structure and properties of nitrile rubber 40 H and 3604 by hot polymerization"

Molecule structure and glass transition temperature of raw rubber of the new nitrile rubber (NBR) 40 H by hot polymerization, and Mooney viscosity and curing characteristics of the compound, as well as thermal-oxidative aging resistance and oil resistance of the vulcanizates, were studied and compared with the traditional hot polymerized product NBR 3604. The results showed that the molecule structure of NBR 40 H was not significantly different from that of NBR 3604, both had similar glass transition temperatures and processing properties, and the mechanical property retention rates after thermal-oxidative aging and immersed in standard refe-rence oil were also similar. NBR 40 H could replace NBR 3604

Load system of segmental T-loops for canine retraction

OBJECTIVES: The orthodontic load system, especially the ideal moment-to-force ratios (M/F), is the commonly used design parameter of segmental T-loops for canine retraction. However, the load system, including M/F, may be affected by the changes in canine angulations and interbracket distance (IBD). Here, we hypothesize that clinical changes in canine position and angulation during canine retraction will significantly affect the load system delivered to the tooth. METHODS: The load systems of two T-loop groups, one for translation (TR) and the other for controlled tipping (CT), from nine bilateral canine retraction patients were made to the targeted values obtained from finite element analyses and validated. Each loop was tested on the corresponding maxillary dental cast obtained in the clinic. The casts were made before and after each treatment interval so that both initial and residual load systems could be obtained. The pre- and post-treatment IBDs were recorded for calculating IBD changes. RESULTS: As the IBDs decreased, the averaged retraction-force-drop per IBD reduction was 36 cN/mm, a 30% drop per 1 mm IBD decrease. The averaged anti-tipping-moment-drops per IBD reductions were 0.02 N-mm/mm for CT and 1.4 N-mm/mm for TR, ~0.6 % and 17% drop per 1 mm IBD decrease, respectively. Consequently, the average M/F increases per 1 mm IBD reduction were 1.24 mm/mm for CT and 6.34 mm/mm for TR. There was significant residual load left, which could continue to move the tooth if the patient missed the scheduled appointment. CONCLUSIONS: Clinical changes in canine position and angulation during canine retraction significantly affect the load system. The initial planned M/F needs to be lower to reach the expected average ideal value. Patients should be required to follow the office visit schedule closely to avoid negative effects due to significant M/F increases with time