Signatures of strong correlation effects in RIXS on Cuprates

Recently, spin excitations in doped cuprates are measured using the resonant inelastic X-ray scattering (RIXS). The paramagnon dispersions show the large hardening effect in the electron-doped systems and seemingly doping-independence in the hole-doped systems, with the energy scales comparable to that of the antiferromagnetic magnons. This anomalous hardening effect was partially explained by using the strong coupling t-J model but with a three-site term(Nature communications 5, 3314 (2014)). However we show that hardening effect is a signature of strong coupling physics even without including this extra term. By considering the t-t'-t"-J model and using the Slave-Boson (SB) mean field theory, we obtain, via the spin-spin susceptibility, the spin excitations in qualitative agreement with the experiments. These anomalies is mainly due to the doping-dependent bandwidth. We further discuss the interplay between particle-hole-like and paramagnon-like excitations in the RIXS measurements.Comment: 7 pages, 6 figure

Microsatellite markers uncover cryptic species of Odontotermes (Termitoidae: Termitidae) from Peninsular Malaysia

Termites from the genus Odontotermes are known to contain numerous species complexes that are difficult to tell apart morphologically or with mitochondrial DNA sequences. We developed markers for one such cryptic species complex, that is, Odontotermes srinakarinensis sp. nov. from Maxwell Hill Forest Reserve (Perak, Malaysia), and characterised them using a sample of 41 termite workers from three voucher samples from the same area. We then genotyped 150 termite individuals from 23 voucher samples/colonies of this species complex from several sites in Peninsular Malaysia. We analysed their population by constructing dendograms from the proportion of shared-alleles between individuals and genetic distances between colonies; additionally, we examined the Bayesian clustering pattern of their genotype data. All methods of analysis indicated that there were two distinct clusters within our data set. After the morphologies of specimens from each cluster were reexamined, we were able to separate the two species morphologically and found that a single diagnostic character found on the mandibles of its soldiers could be used to separate the two species quite accurately. The additional species in the clade was identified as Odontotermes denticulatus after it was matched to type specimens at the NHM London and Cambridge Museum of Zoology

Emergence of topological phases from the extension of two-dimensional lattice with nonsymmorphic symmetries

Young and Kane have given a great insight for 2D Dirac semimetals with nontrivial topology in the presence of nonsymmorphic crystalline symmetry. Based on one of 2D nonsymmorphic square lattice structures they proposed, we further construct a set of 3D minimal tight-binding models via vertically stacking the 2D nonsymmorphic lattice. Specifically, our model provides a platform to generate three topologically semimetallic phases such as Dirac nodal line semimetals, Weyl nodal line semimetals and Weyl semimetals. The off-centered mirror symmetry sufficiently protects nodal lines emerging within mirror-invariant plane with a nontrivial mirror invariant $n_{M\mathbb{Z}}$, whereas twofold screw rotational symmetry protects nontrivial Weyl nodal points with topological charge $C=2$. Interestingly, Weyl nodal loops are generated without mirror symmetry protection, where nontrivial "drumhead" surface states emerge within loops. In the presence of both time-reversal and inversion symmetries, the emergence of weak topological insulator phases is discussed as well.Comment: 8 pages, 6 figures and 1 tabl

Signatures of strong correlation effects in resonant inelastic x-ray scattering studies on cuprates

Recently, spin excitations in doped cuprates have been measured using resonant inelastic x-ray scattering. The paramagnon dispersions show the large hardening effect in the electron-doped systems and seemingly doping independence in the hole-doped systems, with the energy scales comparable to that of the antiferromagnetic (AFM) magnons. This anomalous hardening effect and the lack of softening were partially explained by using the strong-coupling t−J model but with a three-site term [Nat. Commun. 5, 3314 (2014)], although the hardening effect is already present even without the latter. By considering the t−t′−t"−J model and using the slave-boson mean-field theory, we obtain, via the spin-spin susceptibility, the spin excitations in qualitative agreement with the experiments. The doping-dependent bandwidth due to the strong correlation physics is the origin of the hardening effect. We also show that dispersions in the AFM regime, different from those in the paramagnetic (PM) regime, hardly vary with dopant density. These excitations are mainly collective in nature instead of particle-hole-like. We further discuss the interplay and different contributions of these two kinds of excitations in the PM phase and show that the dominance of the collective excitation increases with decreasing dopant concentrations

CXCL-8 Regulates Head and Neck Carcinoma Progression through NOD Signalling Pathway

Head and neck squamous cell carcinoma (HNSCC) ranks sixth among the most common cancers in the world. Interlukin-8 (CXCL-8), a major role in inflammatory response and tumor microenvironment, correlates with tumor progression, metastasis and invasion. We explored CXCL-8 promotes tumor progression in different differentiation HNSCC cells. This project would apply to development on biomarker and target in HNSCC as well as provide a basis of early diagnosis and treatment for clinical. CXCL-8, NOD1 (nucleotide-binding oligomerization domain-containing protein 1) and receptor-interacting protein kinase (RIPK2) levels were detected statistically higher in patient tissue with HNSCC than in non-cancerous matched tissue (NCMT) in the microarray and qRT-PCR study, whereas NOD2 was weakly expressed. Similar results were obtained for CXCL-8, NOD1, NOD2 and RIP2 from RT-PCR and western blotting. High CXCL-8, NOD1 and RIP2 expressions were found on HNSCC patient tissue than that of NCMT, whereas NOD2 was weakly expressed. The analytical results indicate that CXCL-8 is required in NOD 1-mediated signalling pathways in HNSCC

Predictive values of PD‑L1 expression for survival outcomes in patients with cervical cancer: a systematic review and meta-analysis

Objectives: Cervical cancer is one of the most common cancers in women worldwide. Although mortality has declined over the past 30 years in high-income areas, it remains a problem in several countries. Given that the prognosis of patients with recurrent or metastatic disease is poor, it is necessary to identify valuable predictive indicators to estimate survival outcomes in patients with cervical cancer.Material and methods: We searched electronic databases such as PubMed, Web of Science, Embase, Ovid MEDLINE, and the Cochrane Central Register of Controlled Trials, and investigated the relationship between Programmed death-ligand 1(PD-L1) expression and prognosis. Chi squared tests and I2 were utilized to assess study heterogeneity, and publication bias was estimated using Begg’s funnel plot and Egger linear regression test.Results: Thirteen eligible studies with 1422 patients were included. Generally, high PD-L1 expression was conclusively associated with poor overall survival (OS) (HR: 1.31; 95% CI 1.03–1.66, p = 0.025). However, PD-L1 expression demonstrated no association with progression-free survival (HR: 0.93; 0.73–1.19, p = 0.57). High PD-L1 expression with a sample size over 100 indicated a shorter OS (HR: 1.51; 95% CI 1.13–2.01). High expression of PD-L1 in Asians represented a lower OS (HR: 1.52; 1.14–2.03). Overexpression of PD-L1 in tumor cells (HR: 1.57; 1.29–2.10) and tumor-infiltrating immune cells (HR: 1.75; 1.02-2.99) predicted poor OS. High PD-L1 expression (HR: 4.04; 2.58–6.31) showed a lower effect on OS with a cut-off value of 5%.Conclusions: Our results indicate that high PD-L1 expression could be a valuable biomarker for predicting clinical outcomes in patients with cervical cancer