Cosmology with viscous generalized Chaplygin gas in f(Q)f(Q) gravity

We use the hybrid model of bulk viscosity and generalized chaplygin gas (GCG), named the viscous generalized chaplygin gas (VGCG) model, which is thought to be an alternate dark fluid of the universe. We explore the dynamics of the VGCG model in the framework of the non-metricity $f(Q)$ gravity using the functional form $f(Q)=\beta Q^n$, where $\beta$ and $n$ are arbitrary constants. For the purpose of constraining model parameters, we use recent observational datasets such as Observational Hubble data, Baryon Acoustic Oscillations, and Type $Ia$ supernovae data. According to our study, the evolution of the deceleration parameter $q$ and the equation of state (EoS) parameter $w$ show a transition from deceleration to an acceleration phase and its deviation from the $\Lambda$CDM model.Comment: Annals of Physics published versio

Dark energy constraint on equation of state parameter in the Weyl type f(Q,T)f(Q,T) gravity

The equation of state parameter is a significant method for characterizing dark energy models. We investigate the evolution of the equation of state parameter with redshift using a Bayesian analysis of recent observational datasets (the Cosmic Chronometer data (CC) and Pantheon samples). The Chevallier-Polarski-Linder parametrization of the effective equation of state parameter, $\omega_{eff}=\omega_0+\omega_a \left( \frac{z}{1+z}\right)$, where $\omega_0$ and $\omega_a$ are free constants, is confined to the Weyl type $f(Q,T)$ gravity, where $Q$ represents the non-metricity and $T$ is the trace of the energy-momentum tensor. We observe the evolution of the deceleration parameter $q$, the density parameter $\rho$, the pressure $p$, and the effective equation of state parameter $\omega$. The cosmic data limit for $\omega$ does not exclude the possibility of $\omega < -1$. It is seen that the parameter $\omega$ shows a transition from deceleration to acceleration, as well as a shift from $\omega>-1$ to $\omega<-1$.Comment: Annals of Physics accepted versio

Reconstruction of f(Q,T)f(Q,T) Lagrangian for various cosmological scenario

The variety of theories that can account for the dark energy phenomenon encourages current research to concentrate on a more in-depth examination of the potential impacts of modified gravity on both local and cosmic scales. We discuss some cosmological reconstruction in $f(Q,T)$ cosmology (where $Q$ is the non-metricity scalar, and $T$ is the trace of the energy-momentum tensor) corresponding to the evolution background in Friedmann-La\^imatre-Robertson-Walker (FLRW) universe. This helps us to determine how any FLRW cosmology can arise from a specific $f(Q,T)$ theory. We use the reconstruction technique to derive explicit forms of $f(Q,T)$ Lagrangian for the different kinds of matter sources and Einstein's static universe. We also formulate the models using several ansatz forms of the $f(Q,T)$ function for $p=\omega \rho$. We demonstrate that several classes of $f(Q,T)$ theories admit the power-law and de-Sitter solutions in some ranges of $\omega$. Additionally, we reconstruct the cosmological model for the scalar field with a specific form of $f(Q,T)$. These new models with cosmological inspiration may impact gravitational phenomena at other cosmological scales.Comment: PLB published versio

The parameterized complexity of some geometric problems in unbounded dimension

We study the parameterized complexity of the following fundamental geometric problems with respect to the dimension $d$: i) Given $n$ points in \Rd, compute their minimum enclosing cylinder. ii) Given two $n$-point sets in \Rd, decide whether they can be separated by two hyperplanes. iii) Given a system of $n$ linear inequalities with $d$ variables, find a maximum-size feasible subsystem. We show that (the decision versions of) all these problems are W[1]-hard when parameterized by the dimension $d$. %and hence not solvable in ${O}(f(d)n^c)$ time, for any computable function $f$ and constant $c$ %(unless FPT=W[1]). Our reductions also give a $n^{\Omega(d)}$-time lower bound (under the Exponential Time Hypothesis)

Effect of Pre-Harvest Treatment on Yield, Maturity and Quality of Flame Seedless Grape (Vitis vinifera L.)

To improve fruit quality in grape cv. Flame Seedless, application of Ethephon (400 and 500 ppm) and trunk girdling was done at veraison stage. Cluster thinning was done by retaining 100, 75 and 50% of total number of bunches on the vines, and, the rest were removed immediately after full bloom. Highest yield was obtained in the treatment 100% Crop load + 500ppm Ethephon, followed by 75% Crop load + 500ppm Ethephon. The treatment of 50% Crop load + 500ppm Ethephon resulted in maximum bunch weight, lowest percentage of uneven coloured berries, maximum TSS, minimum acidity and maximum TSS:acid ratio, maximum anthocyanin content, advanced maturity by 9 days and had maximum sensory rating. But, in this treatment, yield was significantly lower than in treatments where either 75% or 100% Crop load was retained. Thus, considering yield as well as quality parameters, the treatment 75% Crop load + 500ppm Ethephon was found to be the best

Interaction of divergence-free deceleration parameter in Weyl-type f(Q,T)f(Q,T) gravity

We study an extension of symmetric teleparallel gravity i.e. Weyl-type $f(Q,T)$ gravity and the divergence-free parametrization of the deceleration parameter $q(z) = q_{0}+q_{1}\frac{z(1+z)}{1+z^2}$ ($q_{0}$ and $q_{1}$ are free constants) to explore the evolution of the universe. By considering the above parametric form of $q$, we derive the Hubble solution and further impose it in the Friedmann equations of Weyl-type $f(Q, T)$ gravity. To see whether this model can challenge the $\Lambda$CDM limits, we computed the constraints on the model parameters using the Bayesian analysis for the Observational Hubble data ($OHD$) and the Pantheon sample ($SNe\,Ia$). Furthermore, the deceleration parameter depicts the accelerating behavior of the universe with the present value $q_0$ and the transition redshift $z_t$ (at which the expansion transits from deceleration to acceleration) with $1-\sigma$ and $2-\sigma$ confidence level. We also examine the evolution of the energy density, pressure, and effective equation of state parameters. Finally, we demonstrate that the divergence-free parametric form of the deceleration parameter is consistent with the Weyl-type $f(Q,T)$ gravity.Comment: Chinese Journal of Physics published versio

Primary retroperitoneal mucinous cystadenocarcinoma: a rare surgico-pathological entity

Ovarian cancer (OC) is the seventh most common cancer for females in the world. Epithelial OC is the most predominant pathologic subtype (85%-90%), with five major histotypes- serous, mucinous, endometrioid, brenner and clear cell tumour. Each have three pathological subtypes ie benign, borderline and malignant. Mucinous cystadenomas and carcinomas of the ovary are well-established and common tumors. Primary retroperitoneal mucinous cystadenomas and carcinomas are being very rare and histopathogenesis of which is still uncertain. Most pathologists suggest their origin through mucinous metaplasia in a pre-existing mesothelium-lined cyst. An accurate preoperative diagnosis of these tumors is challenging due to lack of established effective diagnostic measures. Hereby presenting a 50-year-old woman, who visited to the hospital with abdominal distension and discomfort since two months. Sonography and computed tomography scans were performed and showed large predominantly cystic lesion arising from right adnexa. Patient underwent exploratory laparotomy for removal of the tumor. Histology and immunohistochemistry revealed primary retroperitoneal mucinous cystadenocarcinoma

Substitution of galvanising by aluminising of steels

ALUMINISING has been accepted by the Government of India as it substitute for galvanising because of the existing scarcity of zinc. Zinc resources of our country are limited whereas minerals for extraction of aluminium are available in plenty. The Hindustan Steel (P ) Ltd., has decided to have provision for strip aluminising plant at Rourkela and Tata Iron and Steel Co. Ltd., may also be going for strip alum-inising adopting the Sendzimir Process . Bokaro Steel Plant has also made provision for aluminising of steel strip

Earthquake networks based on similar activity patterns

Earthquakes are a complex spatiotemporal phenomenon, the underlying mechanism for which is still not fully understood despite decades of research and analysis. We propose and develop a network approach to earthquake events. In this network, a node represents a spatial location while a link between two nodes represents similar activity patterns in the two different locations. The strength of a link is proportional to the strength of the cross-correlation in activities of two nodes joined by the link. We apply our network approach to a Japanese earthquake catalog spanning the 14-year period 1985-1998. We find strong links representing large correlations between patterns in locations separated by more than 1000 km, corroborating prior observations that earthquake interactions have no characteristic length scale. We find network characteristics not attributable to chance alone, including a large number of network links, high node assortativity, and strong stability over time.Comment: 8 pages text, 9 figures. Updated from previous versio