Topological Unwinding in an Exciton-Polariton Condensate Array

The phase distribution in a Bose-Einstein condensate can realize various topological states which can be classified according to distinct winding numbers. While states with different winding numbers are topologically protected in the linear Schr\"odinger equation, when nonlinearities are introduced, violations of the topological protection can occur, leading to unwinding. Exciton-polariton condensates constitute a weakly nonlinear open dissipative system that is well suited to studying such physics. Here we show that exciton-polariton condensates display a spontaneous phase unwinding from a $\pi$- to zero-state. While such an effect was previously observed in a one-dimensional polariton-condensate array and explained as occurring due to single-particle mode competition, we offer a new explanation in terms of collective phase unwinding of metastable states. We clarify that the collective transition is caused by the combined effect of nonlinearity and topological defects in the condensates. Reanalyzing the experimental data, we find an evidence of the collective phase unwinding.Comment: 8+4 pages, 4+1 figure

Correlated states in twisted double bilayer graphene

Electron-electron interactions play an important role in graphene and related systems and can induce exotic quantum states, especially in a stacked bilayer with a small twist angle. For bilayer graphene where the two layers are twisted by a "magic angle", flat band and strong many-body effects lead to correlated insulating states and superconductivity. In contrast to monolayer graphene, the band structure of untwisted bilayer graphene can be further tuned by a displacement field, providing an extra degree of freedom to control the flat band that should appear when two bilayers are stacked on top of each other. Here, we report the discovery and characterization of such displacement-field tunable electronic phases in twisted double bilayer graphene. We observe insulating states at a half-filled conduction band in an intermediate range of displacement fields. Furthermore, the resistance gap in the correlated insulator increases with respect to the in-plane magnetic fields and we find that the g factor according to spin Zeeman effect is ~2, indicating spin polarization at half filling. These results establish the twisted double bilayer graphene as an easily tunable platform for exploring quantum many-body states

Crossmodal correspondences between visual features and tastes in preschoolers: an exploratory study

IntroductionAdults possess a natural inclination to associate sensory cues derived from distinct modalities, such as the pairing of sweet with pink. However, studies exploring crossmodal correspondences in children, particularly in the sensory pairing of visual features and tastes, are scant, leaving unanswered questions regarding the developmental trajectory of crossmodal correspondences. The present study investigates whether Japanese preschool children demonstrate specific biases in shape–color, shape–taste, and color–taste associations.MethodsIn a series of in-person experiments, 92 children between 3 to 6 years of age completed matching tasks utilizing paper stimuli.ResultsChildren exhibit crossmodal correspondences in shape-color (circle-red and asymmetrical star-yellow), shape–taste (triangle-salty and circle-sweet), and color–taste (yellow-sour, black-bitter, and pink-sweet) associations. Moreover, children’s choices are not influenced by their individual preferences.DiscussionThe crossmodal correspondences observed in this study have been observed in previous research on adults from the same (Japanese) culture, although adults showed more crossmodal correspondences than the children in this study (e.g., pink-circle, triangle-sour, and green-bitter). Thus, while some crossmodal correspondences emerge during childhood, others may require additional time to develop, thereby highlighting the importance of understanding the cognitive mechanisms underlying crossmodal correspondences from an ontogenic perspective

Color-taste correspondence tested by the Stroop task

People consistently associate colors with tastes (e.g., pink-sweet, yellow-sour). However, little has been known on the strength of those color-taste correspondences. The current study examined the congruency effect of color-taste correspondence using two Stroop word categorization tasks. The visual stimuli consisted of food names associated with sweet and sour tastes, presented in different shades of pink and yellow font colors. Participants were instructed to categorize the taste (sweet or sour) of the words in the Stroop word-taste categorization task and to discriminate the font color (pink or yellow) of the words in the Stroop word-color discrimination task. Results showed that participants responded faster in congruent conditions (sweet-pink and sour-yellow) than incongruent conditions (sweet-yellow and sour-pink) in both tasks. Specifically, yellow font colors facilitated the categorization of sour taste words compared to pink font colors, whereas sweet taste words facilitated the discrimination of pink font colors compared to sour taste words. These results provide further evidence for the congruency effect of color-taste correspondence in facilitating the processing of taste-related words and colors. Furthermore, the congruency effect was shown to operate bidirectionally, influencing both the conceptual meaning of tastes and perceptual color perception. This study highlights the significant interference effect of color-taste correspondence on cognitive processing as assessed by the Stroop task

Radiocaesium transfer and radiation exposure of frogs in Fukushima Prefecture

The International Commission on Radiological Protection has proposed an environmental assessment framework. This includes ionising radiation exposure assessment for different frog life-stages, but radiocaesium transfer parameters are unavailable. We collate data from the Fukushima Prefecture (contaminated by the Fukushima accident) and estimate radiocaesium concentration ratio (CR ) values for tadpoles and adult frogs, presenting the largest available amphibian CR dataset. In total, 513 adult frogs and 2540 tadpoles were analysed in 62 and 59 composite samples respectively. Results suggest that equilibrium was reached between water and amphibian radiocaesium activity concentrations circa one-year after the accident. Radiocaesium transfer to tadpoles was higher than to adult frogs. Dose rates were estimated for different life-stages and species in both the aquatic and terrestrial environment. Estimated dose rates to adults and tadpoles were typically similar because external exposure dominated for both organisms; frogspawn dose rates were estimated to be orders of magnitude lower than other life-stages. For the two sites assessed, which were outside of the most contaminated areas of the Fukushima Prefecture, estimated dose rates were below those anticipated to present a risk to wildlife populations; it is likely that dose rates in more contaminated areas were in excess of some effects benchmark values

Hypertrophic pulmonary osteoarthropathy secondary to bronchial adenocarcinoma and coexisting pulmonary tuberculosis: a case report

A 44-year-old man presented with painful swelling of wrists and ankles, severe pain at both tibiae, clubbing of fingers and toes and arthritis in wrist and ankle joints. The chest roentgenogram showed consolidation of the right lower lobe, whereas plain roentgenograms revealed solid periosteal reaction at both tibiae. CT and bronchoscopy confirmed the presence of adenocarcinoma of the right lower lobe. Moreover, mycobacterium of tuberculosis was isolated by culture of the patient's sputum

Lung cancer in patients with tuberculosis

BACKGROUND: Coexistent lung cancer and pulmonary tuberculosis is an urgent problem of thoracic surgery presenting a challenging task for diagnosis and surgical treatment. MATERIALS AND METHODS: From 1990 to 2005, 2218 patients with lung cancer underwent surgical treatment in Department of Thoracic Surgery and Oncology, Institute of Oncology, Vilnius University. In 46 (2.1%) patients coexistence of lung cancer and tuberculosis was found. Central lung cancer was diagnosed in 37 (80.4%) and peripheral – in 9 (19.6%) patients. Epidermoid cancer was diagnosed in 24 (52.2%) patients, adenocarcinoma – in 10 (21.7%) and adenoepidermoid carcinoma – in 12 (26.1%) patients. Stage I cancer was diagnosed in 12 (26.1%), stage II – in 11 (23.9%), and stage IIIA – in 23 (50%) patients. RESULTS: Pneumonectomy was performed in 18 (39.2%), lobectomy in 10 (21.7%), bilobectomy in 10 (21.7%), segmentectomy in 8 (17.4%) patients. Postoperative surgical complications were observed in 9 (19.5%) patients, non-surgical complications occurred in 19 patients (41.3%). Six patients (13.04%) died. Combined treatment was applied to 23 (50%) patients. CONCLUSION: Coexistence of tuberculosis and lung cancer in thoracic surgery is fairly rare. This combination was diagnosed only in 46 cases (2.1%) out of 2218 operated lung cancer patients. Epidermoid carcinoma and stage IIIA disease was diagnosed in 50% of patients. Postoperative surgical complications occurred in 9 patients (19.5%) with lung cancer and tuberculosis. Six patients (13%) died in postoperative period. Surgery is the method of choice in treatment of combination of tuberculosis and lung cancer. Median survival of these patients was 28 ± 2 months

Single Nucleotide Polymorphism WRN Leu1074Phe Is Associated with Prostate Cancer Susceptibility in Chinese Subjects

Deficiencies in the human DNA repair gene WRN are the cause of Werner syndrome, a rare autosomal recessive disorder characterized by premature aging and a predisposition to cancer. This study evaluated the association of WRN Leu1074Phe (rs1801195), a common missense single nucleotide polymorphism in WRN, with prostate cancer susceptibility in Chinese subjects. One hundred and forty-seven prostate cancer patients and 111 male cancer-free control subjects from 3 university hospitals in China were included. Blood samples were obtained from each subject, and the single nucleotide polymorphism WRN Leu1074Phe was genotyped by using a Snapshot assay. The results showed that WRN Leu1074Phe was associated with the risk of prostate cancer in Chinese men and that the TG/GG genotype displayed a decreased prevalence of prostate cancer compared with the TT genotype (OR＝0.58, 95%CI:0.35-0.97, p＝0.039). Through stratified analysis, more significant associations were revealed for the TG/GG genotype in the subgroup with diagnosis age <_ 72 yr (OR＝0.27, 95%CI:0.12-0.61, p＝0.002) and in patients with localized diseases (OR＝0.36, 95%CI:0.19-0.70, p＝0.003). However, no statistically significant difference was found in the subgroup with age ＞72 yr or in patients with advanced diseases. We concluded that the genetic variant Leu1074Phe in the DNA repair gene WRN might play a role in the risk of prostate cancer in Chinese subjects