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Background: Almost a year to the pandemic situation gone, but still no approved scientific treatment only experimental cocktail for novel coronavirus disease. Ayurveda as a complementary medicine, claims the Ayurveda drug has strong immunity boosting and anti-inflammatory benefits against the coronavirus. To get a global recognition, AYUSH system encourages to carry a randomized controlled clinical trial to treat novel coronavirus disease. In this study, we aimed to summarize the effectiveness of Ayurveda interventions and which interventions are most effective in management of COVID19 positive patients. Methods: To ensure relative efficacy of Ayurveda interventions in management of COVID 19 positive patients, we will systematically search randomized controlled trials and quasi-randomised controlled trials in electronic databases. Also, we will search unpublish material from pre-print servers and grey literature. Two independent researchers will conduct the selection process based on inclusion and exclusion criteria according to PRISMA guidelines. Upon selection, we will carry out quality assessment with the help of GRADE and risk of bias assessment using Cochrane Collaboration’s Risk of Bias Assessment Tool. Using R-3.4.1 software to process and analyse data. Result: The results of this study will be published in a peer-reviewed journal. Discussion: The findings from this study will provide directions for further research and provide helpful evidence for clinicians to formulate best Ayurveda treatment strategy for management of COVID-19 positive patients. Systematic review registration: International Prospective Register for Systematic Reviews (PROSPERO) number CRD42021267410.

We present the Sherwood-Relics simulations, a new suite of large cosmological hydrodynamical simulations aimed at modelling the intergalactic medium (IGM) during and after the cosmic reionization of hydrogen. The suite consists of over 200 simulations that cover a wide range of astrophysical and cosmological parameters. It also includes simulations that use a new lightweight hybrid scheme for treating radiative transfer effects. This scheme follows the spatial variations in the ionizing radiation field, as well as the associated fluctuations in IGM temperature and pressure smoothing. It is computationally much cheaper than full radiation hydrodynamics simulations and circumvents the difficult task of calibrating a galaxy formation model to observational constraints on cosmic reionization. Using this hybrid technique, we study the spatial fluctuations in IGM properties that are seeded by patchy cosmic reionization. We investigate the relevant physical processes and assess their impact on the z > 4 Lyman-alpha forest. Our main findings are: (i) Consistent with previous studies patchy reionization causes large scale temperature fluctuations that persist well after the end of reionization, (ii) these increase the Lyman-alpha forest flux power spectrum on large scales, and (iii) result in a spatially varying pressure smoothing that correlates well with the local reionization redshift. (iv) Structures evaporated or puffed up by photoheating cause notable features in the Lyman-alpha forest, such as flat-bottom or double-dip absorption profiles., Version accepted for publication in MNRAS, some discussions added, data added to Fig. 8. 24 pages, 15 figures. Images and movies may be viewed at https://www.nottingham.ac.uk/astronomy/sherwood-relics/

In this Account, we summarize recent developments in Hauser–Kraus (H–K) annulation with respect to syntheses of natural products and other functionalized, fused, or spiro carbocycles and heterocycles. Although the classical H–K annulation occurs between a 1,4-dipolar synthon (a 3-nucleophilic phthalide), and a 1,2-dipolar synthon (a Michael acceptor), alternative modes of annulation, such as [4+4] and [4+1], as well as other reactivities of 3-nucleophilic phthalides that have been reported in recent years, are also covered in this account.1 Introduction2 Hauser–Kraus Annulation in Total Syntheses3 Hauser–Kraus Annulation Methodologies3.1 [4+2] Annulation3.2 [4+4] Annulation Followed by Rearrangement3.3 Michael Addition Followed by E2 Elimination4 Miscellaneous Reactions5 Conclusions

We examine the column density distribution function (CDDF) and Doppler parameter distribution from hydrodynamical simulations and Cosmic Origins Spectrograph (COS) observations of the Lyman-alpha forest at redshift $0\leq z\leq 0.2$. Allowing for a factor of two uncertainty in the metagalactic HI photoionisation rate, our hydrodynamical simulations are in good agreement ($1$-$1.5\sigma$) with the shape and amplitude of the observed CDDF at HI column densities $10^{13.3}\rm\,cm^{-2}\leq N_{\rm HI}\leq 10^{14.5}\rm\,cm^{-2}$. However, the Doppler widths of the simulated lines remain too narrow with respect to the COS data. We argue that invoking AGN feedback does not resolve this discrepancy. We also disfavour enhanced photoheating rates as a potential solution, as this requires an unphysically hard UV background spectrum. If instead appealing to a non-canonical source of heating, an additional specific heat injection of $u \lesssim 6.9\rm\,eV\,m_{\rm p}^{-1}$ is required at $z\lesssim 2.5$ for gas that has $N_{\rm HI}\simeq 10^{13.5}\rm\,cm^{-2}$ by $z=0.1$. Alternatively, there may be an unresolved line of sight turbulent velocity component of $v_{\rm turb}\lesssim 8.5\rm\,km\,s^{-1}(N_{\rm HI}/10^{13.5}\rm\,cm^{-2})^{0.21}$ for the coldest gas in the diffuse IGM., Comment: 21 pages, 13 figures, MNRAS accepted following revision. The accepted version includes an extra panel in figure 2 and some additional clarifications on the line broadening within the models. Conclusions unchanged

Background & Objectives: Pain in Sciatica can be incredibly painful and intolerable which seeks immediate medical attention. Various treatment modalities are widely used but have side effects too. One of them is Ghati Yantra Raktamokshana (Bloodletting with modified cupping). This systematic review provides an assessment on evidence of pain management of Gridhrasi (Sciatica) by Ghati Yantra Raktamokshana (Bloodletting with Modified Cupping). Methods: The databases of PubMed, Scopus, Cochrane Library, AYUSH portal, Shodhganga, Clinical trial registry of India, Google scholar were searched systematically (since inception to February 2021) for relevant articles about the effect of Ghati Yantra Raktamokshana in pain management of Gridhrasi. All randomized controlled trials as well as non-randomized controlled trials, before and after studies and single group clinical studies assessing the efficacy of Ghati Yantra Raktamokshana in pain management of Gridhrasi was included. Results: The original search yielded 774 articles of which only 6 articles (1-pilot study, 1-case study and 4-single arm studies) met the inclusion criteria and they showed the effectiveness of Ghati Yantra Raktamokshana in Pain management of Gridhrasi. Interpretation & Conclusions: Though review shows that the Ghati Yantra Raktamokshana is effective in Pain management of Gridhrasi but due to the methodological and clinical heterogeneity and risk of bias of the included trials requires more strong evidences in terms of RCT’s with larger sample size and for longer duration to definitely conclude its effectiveness.

We use the Sherwood-Relics suite of hybrid hydrodynamical and radiative transfer simulations to model the effect of inhomogeneous reionisation on the 1D power spectrum of the \Lya forest transmitted flux at redshifts $4.2\leq z \leq 5$. Relative to models that assume a homogeneous UV background, reionisation suppresses the power spectrum at small scales, $k \sim 0.1\rm\,km^{-1}\,s$ by $\sim 10$ per cent because of spatial variations in the thermal broadening kernel and the divergent peculiar velocity field associated with over-pressurised intergalactic gas. On larger scales, $k4$, $0.006 \rm \,km^{-1}\,s\leq k \leq 0.2 \rm\, km^{-1}\,s$, we find inhomogeneous reionisation does not introduce any significant bias in thermal parameter recovery for the current measurement uncertainties of $\sim 10$ per cent. However, for $5$ per cent uncertainties, $\sim 1\sigma$ shifts between the estimated and true parameters occur., Comment: Accepted by MNRAS (21 November 2021), 20 pages, 11 figures

Observations of the Lyman-$\alpha$ (Ly$\alpha$) forest in spectra of distant quasars enable us to probe the matter power spectrum at relatively small scales. With several upcoming surveys, it is expected that there will be a many-fold increase in the quantity and quality of data, and hence it is important to develop efficient simulations to forward model these data sets. One such semi-numerical method is based on the assumption that the baryonic densities in the intergalactic medium (IGM) follow a lognormal distribution. In this work, we test the robustness of the lognormal model of the Ly$\alpha$ forest in recovering a set of IGM parameters by comparing with high-resolution Sherwood SPH simulations. We study the recovery of the parameters $T_0$ (temperature of the mean-density IGM), $\gamma$ (slope of the temperature-density relation) and $\Gamma_{12}$ (hydrogen photoionization rate) at $z \sim 2.5$ using a Markov Chain Monte Carlo (MCMC) technique for parameter estimation. Using three flux statistics, the probability distribution, the mean flux and the power spectrum, values of all three parameters, $T_0$, $\gamma$ and $\Gamma_{12}$ implied in the SPH simulations are recovered within $1 - \sigma$ ($\sim$ 9, 4 and 1% respectively) of the median (best-fit) values. We verify the validity of our results at different baryon smoothing filter, SNR, box size & resolution, and data seed and confirm that the lognormal model can be used as an efficient tool for modelling the Ly$\alpha$ transmitted flux at $z \sim 2.5$., Comment: 16 pages, 11 figures; v2: revised version accepted in MNRAS

Enterolithiasis – (stone formation in the small Bowel) is very unusual, and sometime can lead to intestinal obstruction, and Perforation. We are presenting a case report of such an unusual case of enterolithiasis in an old lady.

We present a new investigation of the intergalactic medium (IGM) near reionization using dark gaps in the Lyman-$\beta$ (Ly$\beta$) forest. With its lower optical depth, Ly$\beta$ offers a potentially more sensitive probe to any remaining neutral gas compared to commonly used Ly$\alpha$ line. We identify dark gaps in the Ly$\beta$ forest using spectra of 42 QSOs at $z_{\rm em}>5.5$, including new data from the XQR-30 VLT Large Programme. Approximately $40\%$ of these QSO spectra exhibit dark gaps longer than $10h^{-1}{\rm Mpc}$ at $z\simeq5.8$. By comparing the results to predictions from simulations, we find that the data are broadly consistent both with models where fluctuations in the Ly$\alpha$ forest are caused solely by ionizing ultraviolet background (UVB) fluctuations and with models that include large neutral hydrogen patches at $z, Comment: 17 pages, 13 figures, accepted for publication in ApJ. The Figure set and machine readable table are available at https://ydzhuastro.github.io/lyb.html

We present redshift space two-point ($\xi$), three-point ($\zeta$) and reduced three-point (Q) correlations of Ly$\alpha$ absorbers (Voigt profile components having HI column density, $N_{\rm HI}>10^{13.5}$cm$^{-2}$) over three redshift bins spanning $1.7< z, Comment: 25 pages, 17 figures; Accepted in MNRAS; Comments welcomed

The Ly$\alpha$ forest decomposed into Voigt profile components allow us to study clustering properties of the intergalactic medium and its dependence on various physical quantities. Here, we report the first detections of probability excess of low-z (i.e z10^{14}$cm$^{-2}$ self-consistently or to the widespread of signal-to-noise ratio in the observed data., Comment: 23 pages, 14 figures. Submitted to MNRAS

We characterise the thermal state of the intergalactic medium (IGM) in ten redshift bins in the redshift range $2 \leq z \leq 4$ with a sample of 103 high resolution, high S/N Ly$\alpha$ forest spectra using four different flux distribution statistics. Our measurements are calibrated with mock spectra from a large suite of hydrodynamical simulations post-processed with our thermal IGM evolution code CITE, finely sampling amplitude and slope of the expected temperature-density relation. The thermal parameters inferred from our measurements of the flux power spectrum, Doppler parameter distribution, as well as wavelet and curvature statistics agree well within their respective errors and all clearly show the peak in temperature and minimum in slope of the temperature density relation expected from HeII reionization. Combining our measurements from the different flux statistics gives $T_0=(14750 \pm 1322)$K for the peak temperature at mean density and a corresponding minimum slope $\gamma = 1.225 \pm 0.120$. The peak in the temperature evolution occurs at $z \approx 3$, in agreement with previous measurements that had suggested the presence of such a peak, albeit with a large scatter. Using CITE, we also calculate the thermal state of the IGM predicted by five widely used (spatially homogeneous) UV-background models. The rather rapid thermal evolution inferred by our measurements is well reproduced by two of the models, if we assume (physically well motivated) non-equilibrium evolution with photo-heating rates that are reduced by a moderate factor of $\sim 0.7-0.8$. The other three models predict HeII reionization to be more extended with a somewhat earlier as well as higher temperature peak than our measurements suggest., Comment: 25 pages (+31 pages appendices), 19 figures (+30 figures appendices); Accepted and Published in MNRAS; Main results are summarized in Fig. 16, Fig. 19 and Table 2

We compare a sample of five high-resolution, high S/N Ly$\alpha$ forest spectra of bright $65$ with those obtained from mock absorption spectra from the Sherwood and Sherwood-Relics suites of hydrodynamical simulations of the intergalactic medium (IGM). We use a profile fitting procedure for the inverted transmitted flux, $1-F$, similar to the widely used Voigt profile fitting of the transmitted flux $F$ at lower redshifts, to characterise the transmission spikes that probe predominately underdense regions of the IGM. We are able to reproduce the width and height distributions of the transmission spikes, both with optically thin simulations of the post-reionization Universe using a homogeneous UV background and full radiative transfer simulations of a late reionization model. We find that the width of the fitted components of the simulated transmission spikes is very sensitive to the instantaneous temperature of the reionized IGM. The internal structures of the spikes are more prominant in low temeperature models of the IGM. The width distribution of the observed transmission spikes, which require high spectral resolution ($\leq $ 8 km/s) to be resolved, is reproduced for optically thin simulations with a temperature at mean density of $T_0= (11000 \pm 1600,10500\pm 2100,12000 \pm 2200)$ K at $z= (5.4,5.6,5.8)$. This is weakly dependent on the slope of the temperature-density relation, which is favoured to be moderately steeper than isothermal. In the inhomogeneous, late reionization, full radiative transfer simulations where islands of neutral hydrogen persist to $z\sim5.3$, the width distribution of the observed transmission spikes is consistent with the range of $T_0$ caused by spatial fluctuations in the temperature-density relation., Comment: 20 pages (+10 pages appendices), 12 figures (+14 figures appendices); Accepted in MNRAS; Main results are summarized in Fig. 10, Fig. 12 and Table 3

Ly$\alpha$ forest absorption spectra decomposed into multiple Voigt profile components (clouds) allow us to study clustering of intergalactic medium (IGM) as a function of HI column density ($N_{\rm HI}$). Here, we explore the transverse three-point correlation ($\zeta$) of these Ly$\alpha$ clouds using mock triplet spectra obtained from hydrodynamical simulations at $z \sim 2$ on scales of 1-5 $h^{-1}$cMpc. We find $\zeta$ to depend strongly on $N_{\rm HI}$ and scale and weakly on angle ($\theta$) of the triplet configuration. We show that the "hierarchical ansatz" is applicable for scales $\ge~ 3h^{-1}$cMpc, and obtain a median reduced three-point correlation (Q) in the range 0.2-0.7. We show, $\zeta$ is influenced strongly by the thermal and ionization state of the gas. As found in the case of galaxies, the influence of physical parameters on Q is weaker compared to that of $\zeta$. We show difference in $\zeta$ and Q between different simulations are minimized if we use appropriate $N_{\rm HI}$ cut-offs corresponding to a given baryon over-density ($\Delta$) using the measured $N_{\rm HI}~vs~\Delta$ relationship obtained from individual simulations. Additionally, we see the effect of pressure broadening on $\zeta$ in a model with artificially boosted heating rates. However, for models with realistic thermal and ionization histories the effect of pressure broadening on $\zeta$ is weak and sub-dominant compared to other local effects. We find strong redshift evolution shown by $\zeta$, mainly originating from the redshift evolution of thermal and ionization state of the IGM. We discuss the observational requirements for the detection of three-point correlation, specifically, in small intervals of configuration parameters and redshift., Comment: 26 pages, 23 figures. Submitted to MNRAS

We present analysis of two- and three-point correlation functions of Ly$\alpha$ forest (at $2\le z\le 2.5$) using X-Shooter spectra of three background quasar triplets probing transverse separations of 0.5-1.6 pMpc. We present statistics based on transmitted flux and clouds identified using Voigt profile fitting. We show that the observed two-, three-point correlation functions and reduced three-point correlation (i.e Q) are well reproduced by our simulations. We assign probabilities for realising all the observed correlation properties simultaneously using our simulations. Our simulations suggest an increase in correlation amplitudes and Q with increasing $N_{\rm HI}$. We roughly see this trend in the observations too. We identify a concurrent gap of 17$\mathring{A}$ (i.e 14.2 $h^{-1}$cMpc, one of the longest reported) wide in one of the triplets. Such gap is realised only in 14.2% of our simulated sightlines and most of the time belongs to a void in the matter distribution. In the second triplet, we detect DLAs along all three sightlines (with spatial separations 0.64 to 1.6 pMpc) within a narrow redshift interval (i.e $\Delta z = 0.088$). Detection of a foreground quasar ($\sim$ 1 pMpc from the triplet sightlines) and excess partial Lyman Limit systems around these DLAs suggest that we may be probing a large over-dense region. We also report positive CIV- CIV correlations up to $\sim 500$ $km s^{-1}$ only in the longitudinal direction. Additionally, we conclude a positive CIV-Ly$\alpha$ correlations for higher $N_{\rm HI}$ thresholds up to a scale of $\sim 1000$ $km s^{-1}$ both in transverse and longitudinal directions., Comment: 28 pages, 20 figures. Submitted to MNRAS

We present a post-processing tool for GADGET-2 adiabatic simulations to model various observed properties of the Ly$\alpha$ forest at $2.5 \leq z \leq 4$ that enables an efficient parameter estimation. In particular, we model the thermal and ionization histories that are not computed self-consistently by default in GADGET-2. We capture the effect of pressure smoothing by running GADGET-2 at an elevated temperature floor and using an appropriate smoothing kernel. We validate our procedure by comparing different statistics derived from our method with those derived using self-consistent simulations with GADGET-3. These statistics are: line of sight density field power spectrum, flux probability distribution function, flux power spectrum, wavelet statistics, curvature statistics, HI column density (${\rm N_{HI}}$) distribution function, linewidth ($b$) distribution and $b$ versus $\log {\rm N_{HI}}$ scatter. For the temperature floor of $10^4$ K and typical signal-to-noise of 25, the results agree well within 20 percent of the self-consistent GADGET-3 simulation. However, this difference is smaller than the expected $1\sigma$ sample variance for an absorption path length of $\sim 5.35$ at $z=3$. Moreover for a given cosmology, we gain a factor of $\sim N$ in computing time for modelling the intergalactic medium under $N \gg 1$ different thermal histories. In addition, our method allows us to simulate the non-equilibrium evolution of thermal and ionization state of the gas and include heating due to non-standard sources like cosmic rays and high energy $\gamma$-rays from Blazars., Comment: 29 pages, 26 figures, 8 tables. New figures and tables are included, Accepted for publication in MNRAS

We have developed a parallel code called "VoIgt profile Parameter Estimation Routine (VIPER)" for automatically fitting the H I Ly-$\alpha$ forest seen in the spectra of QSOs. We obtained the H I column density distribution function (CDDF) and line width ($b$) parameter distribution for $z < 0.45$ using spectra of 82 QSOs obtained using Cosmic Origins Spectrograph and VIPER. Consistency of these with the existing measurements in the literature validate our code. By comparing this CDDF with those obtained from hydrodynamical simulation, we constrain the H I photoionization rate ($\Gamma_{\rm HI}$) at $z < 0.45$ in four redshift bins. The VIPER, together with the Code for Ionization and Temperature Evolution (CITE) we have developed for GADGET-2, allows us to explore parameter space and perform $\chi^2$ minimization to obtain $\Gamma_{\rm HI}$. We notice that the $b$ parameters from the simulations are smaller than what are derived from the observations. We show the observed $b$ parameter distribution and $b$ vs $\log {\rm N_{HI}}$ scatter can be reproduced in simulation by introducing sub-grid scale turbulence. However, it has very little influence on the derived $\Gamma_{\rm HI}$. The $\Gamma_{\rm HI}(z)$ obtained here, $(3.9 \pm 0.1) \times 10^{-14} \; (1+z)^{4.98 \pm 0.11} \;{\rm s^{-1}}$, is in good agreement with those derived by us using flux based statistics in the previous paper. These are consistent with the hydrogen ionizing ultra-violet (UV) background being dominated mainly by QSOs without needing any contribution from the non-standard sources of the UV photons., Comment: 17 pages, 10 figures

Any remote sensing image regardless of the source (satellite, aircraft or any sensors and platforms) from which it is acquired undergoes distortion. This generally happens because of the various aspects concerning the optics, scanning mechanism; or motion, velocity, altitude and attitude associated with platforms or may be due rotations and curvature of the earth. Synthetic Aperture Radar (SAR) imaging is one of the emerging technology of remote sensing which has grabbed the attention of most of the researchers. Also, in recent years Compressed Sensing (CS) theory has emerged in both signal processing and image processing domains. Compressed sensing promises image reconstruction at a lower sampling rate than traditional Nyquist sampling and hence CS can also be used for image retrieval. Not only this but CS also provides a faster and efficient way to reproduce the signals. This paper demonstrates the application of CS theory for pre-processing on high-resolution images for SAR image reconstruction.

Non-equilibrium ionization effects are important in cosmological hydrodynamical simulations but are computationally expensive. We study the effect of non-equilibrium ionization evolution and UV ionizing background (UVB) generated with different quasar spectral energy distribution (SED) on the derived physical conditions of the intergalactic medium (IGM) at $2\leq z \leq 6$ using our post-processing tool 'Code for Ionization and Temperature Evolution' (CITE). CITE produces results matching well with self-consistent simulations more efficiently. The HeII reionization progresses more rapidly in non-equilibrium model as compared to equilibrium models. The redshift of HeII reionization strongly depends on the quasar SED and occurs earlier for UVB models with flatter quasar SEDs. During this epoch the normalization of temperature-density relation, $T_0(z)$, has a maximum while the slope, $\gamma(z)$, has a minimum, but occurring at different redshifts. The $T_0$ is higher in non-equilibrium models using UVB obtained with flatter quasar SEDs. While our models produce the observed median HeII effective optical depth evolution and its scatter for equilibrium and non-equilibrium considerations, to explain the observed cumulative distributions we may need to consider fluctuating UVB. For a given UVB model, the redshift dependence of the HI photo-ionization rate derived from the observed HI effective optical depth ($\tau_{\rm eff,HI}$) for the equilibrium model is different from that for the non-equilibrium model. This may lead to different requirements on the evolution of ionizing emissivities of sources. We show that, in the absence of strong differential pressure smoothing effects, it is possible to recover the $T_0$ and $\gamma$ realised in non-equilibrium model from the equilibrium models generated by rescaling photo-heating rates while producing the same $\tau_{\rm eff,HI}$., Comment: 25 pages, 18 figures, Accepted in MNRAS, New figures added (CDF of tau_eff_HeII)