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We study the structure and stability of traversable wormholes built as (spherically symmetric) thin shells in the context of Palatini f(R) gravity. Using a suitable junction formalism for these theories we find that the effective number of degrees of freedom on the shell is reduced to a single one, which fixes the equation of state to be that of massless stress-energy fields, contrary to the general relativistic and metric f(R) cases. Another major difference is that the surface energy density threading the thin shell, needed in order to sustain the wormhole, can take any sign and may even vanish, depending on the desired features of the corresponding solutions. We illustrate our results by constructing thin-shell wormholes by surgically grafting Schwarzschild space-times and show that these configurations are always linearly unstable. However, surgically joined Reissner-Nordstrom space-times allow for linearly stable, traversable thin-shell wormholes supported by a positive energy density provided that the (squared) mass-to-charge ratio, given by y = Q(2)/M-2, satisfies the constraint 1 < y < 9/8 (corresponding to overcharged Reissner-Nordstrom configurations having a photon sphere) and lies in a region bounded by specific curves defined in terms of the (dimensionless) radius of the shell x(0) = R/M.

We present the inflation in the context of warm universe model by contemplating the Dirac-Born-Infeld non-canonical scalar field. We concentrate on warm DBI inflation considering the constant sound of speed. Inflationary theory has ability to provide strong solutions to cosmological puzzles of early universe. We contemplate the Anti-de Sitter warp factor for DBI inflation also, examine viability of the quadratic and quartic potential according to Planck 2018 observational data. We find the slow-roll parameters as well as different inflationary parameters in the presence of well-known potentials. We demonstrate graphical behavior of the $r-N$ , $n_{s}-N$ and $\alpha -N$ for both positive as well as negative potentials. The results of $n_{s}-N$ , $r-N$ and $\alpha -N$ are $0.9525^{+0.0125}_{-0.0125}$ , $-0.00015^{+0.00025}_{-0.00025}$ , $0.03375^{+0.03375}_{-0.03375}$ (for positive quadratic and quartic potential) and $0.98^{+0.03}_{-0.03}$ , $0.05^{+0.05}_{-0.05}$ , $0.0018125^{+0.0018125}_{-0.0018125}$ (for negative quadratic and quartic potential), respectively. Also, we conclude that results of the $r$ , $n_{s}$ and $\alpha $ are consistent with recent Planck data 2018.

We consider a warm inflation universe model in the presence of generalized Chaplygin gas and modified Chaplygin gas by taking Dirac-Born-Infeld non-canonical scalar field. For developing various inflationary parameters, we assume quadratic potential and quartic potential and Anti-de-Sitter warp factor for the Dirac-Born-Infeld inflation. We develop the number of e-folds, scalar as well as tensor power spectrum, scalar spectral index and tensor-scalar ratio in the terms of ϕ under slow-roll approximation by assuming the constant sound speed. We establish the graphical behavior of r − N , n s − N and α − N for both Chaplygin gas models. The results of r − N , n s − N and α − N are 0 . 972 − 0.02 + 0.02 , − 0 . 0005 − 0.001 + 0.001 , 0 . 0004 − 0.0004 + 0.0004 (for generalized Chaplygin gas with quadratic potential) and 0 . 97 − 0.05 + 0.05 , 0 . 0045 − 0.0055 + 0.0055 , 0 . 0045 − 0.0045 + 0.0045 (generalized Chaplygin gas with quartic potential), respectively. Also, the results of inflationary parameters are 0 . 97 − 0.02 + 0.02 , 0 . 0015 − 0.0025 + 0.0025 , 0 . 125 − 0.125 + 0.125 (for modified Chaplygin gas with quadratic potential) and 0 . 94 − 0.05 + 0.05 , 0 . 01 − 0.015 + 0.015 , 0 . 0185 − 0.0185 + 0.0185 (modified Chaplygin gas with quartic potential), respectively. It is found that these results are well matched with 68% and 95% CL constraints of the Planck 2018 TT,TE,EE+lowP+lensing data.

The average time required for cancers to progress through stages can be reflected in the average age of the patients diagnosed at each stage of disease. To estimate the time it takes for non-small-cell lung cancer (NSCLC) to progress through different tumor, node and metastasis (TNM) stages and sizes, we compared the mean adjusted age of 45904 NSCLC patients with different stages and tumor sizes from Surveillance, Epidemiology and End Results (SEER) cancer registry database and our institute. Multiple-linear-regression models for age were generated adjusting for various factors. Caucasian, African-American and Asian patients with stage IA cancers were on average 0.8, 1.0 and 1.38 adjusted years younger, respectively, than those with stage IIIB cancers (p

Alveolar adenoma, a rare benign pulmonary neoplasm, usually presents as asymptomatic. Since first described in 1986, no more than 35 cases have been reported in the English medical literature. Here we report a case of 48-year-old woman who suffered from this tumor, the patient is doing well 4 years after thoracoscopic lobectomy.

Robot-assisted thoracic surgery (RATS) is a relatively new but rapidly adopted technique, pioneered by the urological and gynecological departments. The primary objective of this study is to present the current status, a series of improvement and innovation of Da Vinci robotic surgery in the Department of Thoracic Surgery at First Affiliated Hospital of Zhejiang University. In addition, we discuss the prospect of robotic surgical technology.